1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/stat.h>
18 #include <sys/queue.h>
19 
20 #include <dirent.h>
21 #include <limits.h>
22 #include <stddef.h>
23 #include <string.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <time.h>
27 #include <fcntl.h>
28 #include <errno.h>
29 #include <unistd.h>
30 #include <zlib.h>
31 #include <fnmatch.h>
32 #include <libgen.h>
33 
34 #include "got_compat.h"
35 
36 #include "got_error.h"
37 #include "got_repository.h"
38 #include "got_reference.h"
39 #include "got_object.h"
40 #include "got_path.h"
41 #include "got_cancel.h"
42 #include "got_worktree.h"
43 #include "got_opentemp.h"
44 #include "got_diff.h"
45 
46 #include "got_lib_worktree.h"
47 #include "got_lib_sha1.h"
48 #include "got_lib_fileindex.h"
49 #include "got_lib_inflate.h"
50 #include "got_lib_delta.h"
51 #include "got_lib_object.h"
52 #include "got_lib_object_parse.h"
53 #include "got_lib_object_create.h"
54 #include "got_lib_object_idset.h"
55 #include "got_lib_diff.h"
56 #include "got_lib_gotconfig.h"
57 
58 #ifndef MIN
59 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
60 #endif
61 
62 #define GOT_MERGE_LABEL_MERGED	"merged change"
63 #define GOT_MERGE_LABEL_BASE	"3-way merge base"
64 
65 static mode_t		 apply_umask(mode_t);
66 
67 static const struct got_error *
68 create_meta_file(const char *path_got, const char *name, const char *content)
69 {
70 	const struct got_error *err = NULL;
71 	char *path;
72 
73 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
74 		return got_error_from_errno("asprintf");
75 
76 	err = got_path_create_file(path, content);
77 	free(path);
78 	return err;
79 }
80 
81 static const struct got_error *
82 update_meta_file(const char *path_got, const char *name, const char *content)
83 {
84 	const struct got_error *err = NULL;
85 	FILE *tmpfile = NULL;
86 	char *tmppath = NULL;
87 	char *path = NULL;
88 
89 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
90 		err = got_error_from_errno("asprintf");
91 		path = NULL;
92 		goto done;
93 	}
94 
95 	err = got_opentemp_named(&tmppath, &tmpfile, path, "");
96 	if (err)
97 		goto done;
98 
99 	if (content) {
100 		int len = fprintf(tmpfile, "%s\n", content);
101 		if (len != strlen(content) + 1) {
102 			err = got_error_from_errno2("fprintf", tmppath);
103 			goto done;
104 		}
105 	}
106 
107 	if (rename(tmppath, path) != 0) {
108 		err = got_error_from_errno3("rename", tmppath, path);
109 		unlink(tmppath);
110 		goto done;
111 	}
112 
113 done:
114 	if (fclose(tmpfile) == EOF && err == NULL)
115 		err = got_error_from_errno2("fclose", tmppath);
116 	free(tmppath);
117 	return err;
118 }
119 
120 static const struct got_error *
121 write_head_ref(const char *path_got, struct got_reference *head_ref)
122 {
123 	const struct got_error *err = NULL;
124 	char *refstr = NULL;
125 
126 	if (got_ref_is_symbolic(head_ref)) {
127 		refstr = got_ref_to_str(head_ref);
128 		if (refstr == NULL)
129 			return got_error_from_errno("got_ref_to_str");
130 	} else {
131 		refstr = strdup(got_ref_get_name(head_ref));
132 		if (refstr == NULL)
133 			return got_error_from_errno("strdup");
134 	}
135 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
136 	free(refstr);
137 	return err;
138 }
139 
140 const struct got_error *
141 got_worktree_init(const char *path, struct got_reference *head_ref,
142     const char *prefix, struct got_repository *repo)
143 {
144 	const struct got_error *err = NULL;
145 	struct got_object_id *commit_id = NULL;
146 	uuid_t uuid;
147 	uint32_t uuid_status;
148 	int obj_type;
149 	char *path_got = NULL;
150 	char *formatstr = NULL;
151 	char *absprefix = NULL;
152 	char *basestr = NULL;
153 	char *uuidstr = NULL;
154 
155 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
156 		err = got_error(GOT_ERR_WORKTREE_REPO);
157 		goto done;
158 	}
159 
160 	err = got_ref_resolve(&commit_id, repo, head_ref);
161 	if (err)
162 		return err;
163 	err = got_object_get_type(&obj_type, repo, commit_id);
164 	if (err)
165 		return err;
166 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
167 		return got_error(GOT_ERR_OBJ_TYPE);
168 
169 	if (!got_path_is_absolute(prefix)) {
170 		if (asprintf(&absprefix, "/%s", prefix) == -1)
171 			return got_error_from_errno("asprintf");
172 	}
173 
174 	/* Create top-level directory (may already exist). */
175 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
176 		err = got_error_from_errno2("mkdir", path);
177 		goto done;
178 	}
179 
180 	/* Create .got directory (may already exist). */
181 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
182 		err = got_error_from_errno("asprintf");
183 		goto done;
184 	}
185 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
186 		err = got_error_from_errno2("mkdir", path_got);
187 		goto done;
188 	}
189 
190 	/* Create an empty lock file. */
191 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
192 	if (err)
193 		goto done;
194 
195 	/* Create an empty file index. */
196 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
197 	if (err)
198 		goto done;
199 
200 	/* Write the HEAD reference. */
201 	err = write_head_ref(path_got, head_ref);
202 	if (err)
203 		goto done;
204 
205 	/* Record our base commit. */
206 	err = got_object_id_str(&basestr, commit_id);
207 	if (err)
208 		goto done;
209 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
210 	if (err)
211 		goto done;
212 
213 	/* Store path to repository. */
214 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
215 	    got_repo_get_path(repo));
216 	if (err)
217 		goto done;
218 
219 	/* Store in-repository path prefix. */
220 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
221 	    absprefix ? absprefix : prefix);
222 	if (err)
223 		goto done;
224 
225 	/* Generate UUID. */
226 	uuid_create(&uuid, &uuid_status);
227 	if (uuid_status != uuid_s_ok) {
228 		err = got_error_uuid(uuid_status, "uuid_create");
229 		goto done;
230 	}
231 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
232 	if (uuid_status != uuid_s_ok) {
233 		err = got_error_uuid(uuid_status, "uuid_to_string");
234 		goto done;
235 	}
236 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
237 	if (err)
238 		goto done;
239 
240 	/* Stamp work tree with format file. */
241 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
242 		err = got_error_from_errno("asprintf");
243 		goto done;
244 	}
245 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
246 	if (err)
247 		goto done;
248 
249 done:
250 	free(commit_id);
251 	free(path_got);
252 	free(formatstr);
253 	free(absprefix);
254 	free(basestr);
255 	free(uuidstr);
256 	return err;
257 }
258 
259 const struct got_error *
260 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
261     const char *path_prefix)
262 {
263 	char *absprefix = NULL;
264 
265 	if (!got_path_is_absolute(path_prefix)) {
266 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
267 			return got_error_from_errno("asprintf");
268 	}
269 	*match = (strcmp(absprefix ? absprefix : path_prefix,
270 	    worktree->path_prefix) == 0);
271 	free(absprefix);
272 	return NULL;
273 }
274 
275 const char *
276 got_worktree_get_head_ref_name(struct got_worktree *worktree)
277 {
278 	return worktree->head_ref_name;
279 }
280 
281 const struct got_error *
282 got_worktree_set_head_ref(struct got_worktree *worktree,
283     struct got_reference *head_ref)
284 {
285 	const struct got_error *err = NULL;
286 	char *path_got = NULL, *head_ref_name = NULL;
287 
288 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
289 	    GOT_WORKTREE_GOT_DIR) == -1) {
290 		err = got_error_from_errno("asprintf");
291 		path_got = NULL;
292 		goto done;
293 	}
294 
295 	head_ref_name = strdup(got_ref_get_name(head_ref));
296 	if (head_ref_name == NULL) {
297 		err = got_error_from_errno("strdup");
298 		goto done;
299 	}
300 
301 	err = write_head_ref(path_got, head_ref);
302 	if (err)
303 		goto done;
304 
305 	free(worktree->head_ref_name);
306 	worktree->head_ref_name = head_ref_name;
307 done:
308 	free(path_got);
309 	if (err)
310 		free(head_ref_name);
311 	return err;
312 }
313 
314 struct got_object_id *
315 got_worktree_get_base_commit_id(struct got_worktree *worktree)
316 {
317 	return worktree->base_commit_id;
318 }
319 
320 const struct got_error *
321 got_worktree_set_base_commit_id(struct got_worktree *worktree,
322     struct got_repository *repo, struct got_object_id *commit_id)
323 {
324 	const struct got_error *err;
325 	struct got_object *obj = NULL;
326 	char *id_str = NULL;
327 	char *path_got = NULL;
328 
329 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
330 	    GOT_WORKTREE_GOT_DIR) == -1) {
331 		err = got_error_from_errno("asprintf");
332 		path_got = NULL;
333 		goto done;
334 	}
335 
336 	err = got_object_open(&obj, repo, commit_id);
337 	if (err)
338 		return err;
339 
340 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
341 		err = got_error(GOT_ERR_OBJ_TYPE);
342 		goto done;
343 	}
344 
345 	/* Record our base commit. */
346 	err = got_object_id_str(&id_str, commit_id);
347 	if (err)
348 		goto done;
349 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
350 	if (err)
351 		goto done;
352 
353 	free(worktree->base_commit_id);
354 	worktree->base_commit_id = got_object_id_dup(commit_id);
355 	if (worktree->base_commit_id == NULL) {
356 		err = got_error_from_errno("got_object_id_dup");
357 		goto done;
358 	}
359 done:
360 	if (obj)
361 		got_object_close(obj);
362 	free(id_str);
363 	free(path_got);
364 	return err;
365 }
366 
367 const struct got_gotconfig *
368 got_worktree_get_gotconfig(struct got_worktree *worktree)
369 {
370 	return worktree->gotconfig;
371 }
372 
373 static const struct got_error *
374 lock_worktree(struct got_worktree *worktree, int operation)
375 {
376 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
377 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
378 		    : got_error_from_errno2("flock",
379 		    got_worktree_get_root_path(worktree)));
380 	return NULL;
381 }
382 
383 static const struct got_error *
384 add_dir_on_disk(struct got_worktree *worktree, const char *path)
385 {
386 	const struct got_error *err = NULL;
387 	char *abspath;
388 
389 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
390 		return got_error_from_errno("asprintf");
391 
392 	err = got_path_mkdir(abspath);
393 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
394 		struct stat sb;
395 		err = NULL;
396 		if (lstat(abspath, &sb) == -1) {
397 			err = got_error_from_errno2("lstat", abspath);
398 		} else if (!S_ISDIR(sb.st_mode)) {
399 			/* TODO directory is obstructed; do something */
400 			err = got_error_path(abspath, GOT_ERR_FILE_OBSTRUCTED);
401 		}
402 	}
403 	free(abspath);
404 	return err;
405 }
406 
407 static const struct got_error *
408 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
409 {
410 	const struct got_error *err = NULL;
411 	uint8_t fbuf1[8192];
412 	uint8_t fbuf2[8192];
413 	size_t flen1 = 0, flen2 = 0;
414 
415 	*same = 1;
416 
417 	for (;;) {
418 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
419 		if (flen1 == 0 && ferror(f1)) {
420 			err = got_error_from_errno("fread");
421 			break;
422 		}
423 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
424 		if (flen2 == 0 && ferror(f2)) {
425 			err = got_error_from_errno("fread");
426 			break;
427 		}
428 		if (flen1 == 0) {
429 			if (flen2 != 0)
430 				*same = 0;
431 			break;
432 		} else if (flen2 == 0) {
433 			if (flen1 != 0)
434 				*same = 0;
435 			break;
436 		} else if (flen1 == flen2) {
437 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
438 				*same = 0;
439 				break;
440 			}
441 		} else {
442 			*same = 0;
443 			break;
444 		}
445 	}
446 
447 	return err;
448 }
449 
450 static const struct got_error *
451 check_files_equal(int *same, FILE *f1, FILE *f2)
452 {
453 	struct stat sb;
454 	size_t size1, size2;
455 
456 	*same = 1;
457 
458 	if (fstat(fileno(f1), &sb) != 0)
459 		return got_error_from_errno("fstat");
460 	size1 = sb.st_size;
461 
462 	if (fstat(fileno(f2), &sb) != 0)
463 		return got_error_from_errno("fstat");
464 	size2 = sb.st_size;
465 
466 	if (size1 != size2) {
467 		*same = 0;
468 		return NULL;
469 	}
470 
471 	if (fseek(f1, 0L, SEEK_SET) == -1)
472 		return got_ferror(f1, GOT_ERR_IO);
473 	if (fseek(f2, 0L, SEEK_SET) == -1)
474 		return got_ferror(f2, GOT_ERR_IO);
475 
476 	return check_file_contents_equal(same, f1, f2);
477 }
478 
479 static const struct got_error *
480 copy_file_to_fd(off_t *outsize, FILE *f, int outfd)
481 {
482 	uint8_t fbuf[65536];
483 	size_t flen;
484 	ssize_t outlen;
485 
486 	*outsize = 0;
487 
488 	if (fseek(f, 0L, SEEK_SET) == -1)
489 		return got_ferror(f, GOT_ERR_IO);
490 
491 	for (;;) {
492 		flen = fread(fbuf, 1, sizeof(fbuf), f);
493 		if (flen == 0) {
494 			if (ferror(f))
495 				return got_error_from_errno("fread");
496 			if (feof(f))
497 				break;
498 		}
499 		outlen = write(outfd, fbuf, flen);
500 		if (outlen == -1)
501 			return got_error_from_errno("write");
502 		if (outlen != flen)
503 			return got_error(GOT_ERR_IO);
504 		*outsize += outlen;
505 	}
506 
507 	return NULL;
508 }
509 
510 static const struct got_error *
511 merge_binary_file(int *overlapcnt, int merged_fd,
512     FILE *f_deriv, FILE *f_orig, FILE *f_deriv2,
513     const char *label_deriv, const char *label_orig, const char *label_deriv2,
514     const char *ondisk_path)
515 {
516 	const struct got_error *err = NULL;
517 	int same_content, changed_deriv, changed_deriv2;
518 	int fd_orig = -1, fd_deriv = -1, fd_deriv2 = -1;
519 	off_t size_orig = 0, size_deriv = 0, size_deriv2 = 0;
520 	char *path_orig = NULL, *path_deriv = NULL, *path_deriv2 = NULL;
521 	char *base_path_orig = NULL, *base_path_deriv = NULL;
522 	char *base_path_deriv2 = NULL;
523 
524 	*overlapcnt = 0;
525 
526 	err = check_files_equal(&same_content, f_deriv, f_deriv2);
527 	if (err)
528 		return err;
529 
530 	if (same_content)
531 		return copy_file_to_fd(&size_deriv, f_deriv, merged_fd);
532 
533 	err = check_files_equal(&same_content, f_deriv, f_orig);
534 	if (err)
535 		return err;
536 	changed_deriv = !same_content;
537 	err = check_files_equal(&same_content, f_deriv2, f_orig);
538 	if (err)
539 		return err;
540 	changed_deriv2 = !same_content;
541 
542 	if (changed_deriv && changed_deriv2) {
543 		*overlapcnt = 1;
544 		if (asprintf(&base_path_orig, "%s-orig", ondisk_path) == -1) {
545 			err = got_error_from_errno("asprintf");
546 			goto done;
547 		}
548 		if (asprintf(&base_path_deriv, "%s-1", ondisk_path) == -1) {
549 			err = got_error_from_errno("asprintf");
550 			goto done;
551 		}
552 		if (asprintf(&base_path_deriv2, "%s-2", ondisk_path) == -1) {
553 			err = got_error_from_errno("asprintf");
554 			goto done;
555 		}
556 		err = got_opentemp_named_fd(&path_orig, &fd_orig,
557 		    base_path_orig, "");
558 		if (err)
559 			goto done;
560 		err = got_opentemp_named_fd(&path_deriv, &fd_deriv,
561 		    base_path_deriv, "");
562 		if (err)
563 			goto done;
564 		err = got_opentemp_named_fd(&path_deriv2, &fd_deriv2,
565 		    base_path_deriv2, "");
566 		if (err)
567 			goto done;
568 		err = copy_file_to_fd(&size_orig, f_orig, fd_orig);
569 		if (err)
570 			goto done;
571 		err = copy_file_to_fd(&size_deriv, f_deriv, fd_deriv);
572 		if (err)
573 			goto done;
574 		err = copy_file_to_fd(&size_deriv2, f_deriv2, fd_deriv2);
575 		if (err)
576 			goto done;
577 		if (dprintf(merged_fd, "Binary files differ and cannot be "
578 		    "merged automatically:\n") < 0) {
579 			err = got_error_from_errno("dprintf");
580 			goto done;
581 		}
582 		if (dprintf(merged_fd, "%s%s%s\nfile %s\n",
583 		    GOT_DIFF_CONFLICT_MARKER_BEGIN,
584 		    label_deriv ? " " : "",
585 		    label_deriv ? label_deriv : "",
586 		    path_deriv) < 0) {
587 			err = got_error_from_errno("dprintf");
588 			goto done;
589 		}
590 		if (size_orig > 0) {
591 			if (dprintf(merged_fd, "%s%s%s\nfile %s\n",
592 			    GOT_DIFF_CONFLICT_MARKER_ORIG,
593 			    label_orig ? " " : "",
594 			    label_orig ? label_orig : "",
595 			    path_orig) < 0) {
596 				err = got_error_from_errno("dprintf");
597 				goto done;
598 			}
599 		}
600 		if (dprintf(merged_fd, "%s\nfile %s\n%s%s%s\n",
601 		    GOT_DIFF_CONFLICT_MARKER_SEP,
602 		    path_deriv2,
603 		    GOT_DIFF_CONFLICT_MARKER_END,
604 		    label_deriv2 ?  " " : "",
605 		    label_deriv2 ? label_deriv2 : "") < 0) {
606 			err = got_error_from_errno("dprintf");
607 			goto done;
608 		}
609 	} else if (changed_deriv)
610 		err = copy_file_to_fd(&size_deriv, f_deriv, merged_fd);
611 	else if (changed_deriv2)
612 		err = copy_file_to_fd(&size_deriv2, f_deriv2, merged_fd);
613 done:
614 	if (size_orig == 0 && path_orig && unlink(path_orig) == -1 &&
615 	    err == NULL)
616 		err = got_error_from_errno2("unlink", path_orig);
617 	if (fd_orig != -1 && close(fd_orig) == -1 && err == NULL)
618 		err = got_error_from_errno2("close", path_orig);
619 	if (fd_deriv != -1 && close(fd_deriv) == -1 && err == NULL)
620 		err = got_error_from_errno2("close", path_deriv);
621 	if (fd_deriv2 != -1 && close(fd_deriv2) == -1 && err == NULL)
622 		err = got_error_from_errno2("close", path_deriv2);
623 	free(path_orig);
624 	free(path_deriv);
625 	free(path_deriv2);
626 	free(base_path_orig);
627 	free(base_path_deriv);
628 	free(base_path_deriv2);
629 	return err;
630 }
631 
632 /*
633  * Perform a 3-way merge where the file f_orig acts as the common
634  * ancestor, the file f_deriv acts as the first derived version,
635  * and the file f_deriv2 acts as the second derived version.
636  * The merge result will be written to a new file at ondisk_path; any
637  * existing file at this path will be replaced.
638  */
639 static const struct got_error *
640 merge_file(int *local_changes_subsumed, struct got_worktree *worktree,
641     FILE *f_orig, FILE *f_deriv, FILE *f_deriv2, const char *ondisk_path,
642     const char *path, uint16_t st_mode,
643     const char *label_orig, const char *label_deriv, const char *label_deriv2,
644     enum got_diff_algorithm diff_algo, struct got_repository *repo,
645     got_worktree_checkout_cb progress_cb, void *progress_arg)
646 {
647 	const struct got_error *err = NULL;
648 	int merged_fd = -1;
649 	FILE *f_merged = NULL;
650 	char *merged_path = NULL, *base_path = NULL;
651 	int overlapcnt = 0;
652 	char *parent = NULL;
653 
654 	*local_changes_subsumed = 0;
655 
656 	err = got_path_dirname(&parent, ondisk_path);
657 	if (err)
658 		return err;
659 
660 	if (asprintf(&base_path, "%s/got-merged", parent) == -1) {
661 		err = got_error_from_errno("asprintf");
662 		goto done;
663 	}
664 
665 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path, "");
666 	if (err)
667 		goto done;
668 
669 	err = got_merge_diff3(&overlapcnt, merged_fd, f_deriv, f_orig,
670 	    f_deriv2, label_deriv, label_orig, label_deriv2, diff_algo);
671 	if (err) {
672 		if (err->code != GOT_ERR_FILE_BINARY)
673 			goto done;
674 		err = merge_binary_file(&overlapcnt, merged_fd, f_deriv,
675 		    f_orig, f_deriv2, label_deriv, label_orig, label_deriv2,
676 		    ondisk_path);
677 		if (err)
678 			goto done;
679 	}
680 
681 	err = (*progress_cb)(progress_arg,
682 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
683 	if (err)
684 		goto done;
685 
686 	if (fsync(merged_fd) != 0) {
687 		err = got_error_from_errno("fsync");
688 		goto done;
689 	}
690 
691 	f_merged = fdopen(merged_fd, "r");
692 	if (f_merged == NULL) {
693 		err = got_error_from_errno("fdopen");
694 		goto done;
695 	}
696 	merged_fd = -1;
697 
698 	/* Check if a clean merge has subsumed all local changes. */
699 	if (overlapcnt == 0) {
700 		err = check_files_equal(local_changes_subsumed, f_deriv,
701 		    f_merged);
702 		if (err)
703 			goto done;
704 	}
705 
706 	if (fchmod(fileno(f_merged), apply_umask(st_mode)) != 0) {
707 		err = got_error_from_errno2("fchmod", merged_path);
708 		goto done;
709 	}
710 
711 	if (rename(merged_path, ondisk_path) != 0) {
712 		err = got_error_from_errno3("rename", merged_path,
713 		    ondisk_path);
714 		goto done;
715 	}
716 done:
717 	if (err) {
718 		if (merged_path)
719 			unlink(merged_path);
720 	}
721 	if (merged_fd != -1 && close(merged_fd) == -1 && err == NULL)
722 		err = got_error_from_errno("close");
723 	if (f_merged && fclose(f_merged) == EOF && err == NULL)
724 		err = got_error_from_errno("fclose");
725 	free(merged_path);
726 	free(base_path);
727 	free(parent);
728 	return err;
729 }
730 
731 static const struct got_error *
732 update_symlink(const char *ondisk_path, const char *target_path,
733     size_t target_len)
734 {
735 	/* This is not atomic but matches what 'ln -sf' does. */
736 	if (unlink(ondisk_path) == -1)
737 		return got_error_from_errno2("unlink", ondisk_path);
738 	if (symlink(target_path, ondisk_path) == -1)
739 		return got_error_from_errno3("symlink", target_path,
740 		    ondisk_path);
741 	return NULL;
742 }
743 
744 /*
745  * Overwrite a symlink (or a regular file in case there was a "bad" symlink)
746  * in the work tree with a file that contains conflict markers and the
747  * conflicting target paths of the original version, a "derived version"
748  * of a symlink from an incoming change, and a local version of the symlink.
749  *
750  * The original versions's target path can be NULL if it is not available,
751  * such as if both derived versions added a new symlink at the same path.
752  *
753  * The incoming derived symlink target is NULL in case the incoming change
754  * has deleted this symlink.
755  */
756 static const struct got_error *
757 install_symlink_conflict(const char *deriv_target,
758     struct got_object_id *deriv_base_commit_id, const char *orig_target,
759     const char *label_orig, const char *local_target, const char *ondisk_path)
760 {
761 	const struct got_error *err;
762 	char *id_str = NULL, *label_deriv = NULL, *path = NULL;
763 	FILE *f = NULL;
764 
765 	err = got_object_id_str(&id_str, deriv_base_commit_id);
766 	if (err)
767 		return got_error_from_errno("asprintf");
768 
769 	if (asprintf(&label_deriv, "%s: commit %s",
770 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
771 		err = got_error_from_errno("asprintf");
772 		goto done;
773 	}
774 
775 	err = got_opentemp_named(&path, &f, "got-symlink-conflict", "");
776 	if (err)
777 		goto done;
778 
779 	if (fchmod(fileno(f), apply_umask(GOT_DEFAULT_FILE_MODE)) == -1) {
780 		err = got_error_from_errno2("fchmod", path);
781 		goto done;
782 	}
783 
784 	if (fprintf(f, "%s %s\n%s\n%s%s%s%s%s\n%s\n%s\n",
785 	    GOT_DIFF_CONFLICT_MARKER_BEGIN, label_deriv,
786 	    deriv_target ? deriv_target : "(symlink was deleted)",
787 	    orig_target ? label_orig : "",
788 	    orig_target ? "\n" : "",
789 	    orig_target ? orig_target : "",
790 	    orig_target ? "\n" : "",
791 	    GOT_DIFF_CONFLICT_MARKER_SEP,
792 	    local_target, GOT_DIFF_CONFLICT_MARKER_END) < 0) {
793 		err = got_error_from_errno2("fprintf", path);
794 		goto done;
795 	}
796 
797 	if (unlink(ondisk_path) == -1) {
798 		err = got_error_from_errno2("unlink", ondisk_path);
799 		goto done;
800 	}
801 	if (rename(path, ondisk_path) == -1) {
802 		err = got_error_from_errno3("rename", path, ondisk_path);
803 		goto done;
804 	}
805 done:
806 	if (f != NULL && fclose(f) == EOF && err == NULL)
807 		err = got_error_from_errno2("fclose", path);
808 	free(path);
809 	free(id_str);
810 	free(label_deriv);
811 	return err;
812 }
813 
814 /* forward declaration */
815 static const struct got_error *
816 merge_blob(int *, struct got_worktree *, struct got_blob_object *,
817     const char *, const char *, uint16_t, const char *,
818     struct got_blob_object *, struct got_object_id *,
819     struct got_repository *, got_worktree_checkout_cb, void *);
820 
821 /*
822  * Merge a symlink into the work tree, where blob_orig acts as the common
823  * ancestor, deriv_target is the link target of the first derived version,
824  * and the symlink on disk acts as the second derived version.
825  * Assume that contents of both blobs represent symlinks.
826  */
827 static const struct got_error *
828 merge_symlink(struct got_worktree *worktree,
829     struct got_blob_object *blob_orig, const char *ondisk_path,
830     const char *path, const char *label_orig, const char *deriv_target,
831     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
832     got_worktree_checkout_cb progress_cb, void *progress_arg)
833 {
834 	const struct got_error *err = NULL;
835 	char *ancestor_target = NULL;
836 	struct stat sb;
837 	ssize_t ondisk_len, deriv_len;
838 	char ondisk_target[PATH_MAX];
839 	int have_local_change = 0;
840 	int have_incoming_change = 0;
841 
842 	if (lstat(ondisk_path, &sb) == -1)
843 		return got_error_from_errno2("lstat", ondisk_path);
844 
845 	ondisk_len = readlink(ondisk_path, ondisk_target,
846 	    sizeof(ondisk_target));
847 	if (ondisk_len == -1) {
848 		err = got_error_from_errno2("readlink",
849 		    ondisk_path);
850 		goto done;
851 	}
852 	ondisk_target[ondisk_len] = '\0';
853 
854 	if (blob_orig) {
855 		err = got_object_blob_read_to_str(&ancestor_target, blob_orig);
856 		if (err)
857 			goto done;
858 	}
859 
860 	if (ancestor_target == NULL ||
861 	    (ondisk_len != strlen(ancestor_target) ||
862 	    memcmp(ondisk_target, ancestor_target, ondisk_len) != 0))
863 		have_local_change = 1;
864 
865 	deriv_len = strlen(deriv_target);
866 	if (ancestor_target == NULL ||
867 	    (deriv_len != strlen(ancestor_target) ||
868 	    memcmp(deriv_target, ancestor_target, deriv_len) != 0))
869 		have_incoming_change = 1;
870 
871 	if (!have_local_change && !have_incoming_change) {
872 		if (ancestor_target) {
873 			/* Both sides made the same change. */
874 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
875 			    path);
876 		} else if (deriv_len == ondisk_len &&
877 		    memcmp(ondisk_target, deriv_target, deriv_len) == 0) {
878 			/* Both sides added the same symlink. */
879 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
880 			    path);
881 		} else {
882 			/* Both sides added symlinks which don't match. */
883 			err = install_symlink_conflict(deriv_target,
884 			    deriv_base_commit_id, ancestor_target,
885 			    label_orig, ondisk_target, ondisk_path);
886 			if (err)
887 				goto done;
888 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
889 			    path);
890 		}
891 	} else if (!have_local_change && have_incoming_change) {
892 		/* Apply the incoming change. */
893 		err = update_symlink(ondisk_path, deriv_target,
894 		    strlen(deriv_target));
895 		if (err)
896 			goto done;
897 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
898 	} else if (have_local_change && have_incoming_change) {
899 		if (deriv_len == ondisk_len &&
900 		    memcmp(deriv_target, ondisk_target, deriv_len) == 0) {
901 			/* Both sides made the same change. */
902 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
903 			    path);
904 		} else {
905 			err = install_symlink_conflict(deriv_target,
906 			    deriv_base_commit_id, ancestor_target, label_orig,
907 			    ondisk_target, ondisk_path);
908 			if (err)
909 				goto done;
910 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
911 			    path);
912 		}
913 	}
914 
915 done:
916 	free(ancestor_target);
917 	return err;
918 }
919 
920 static const struct got_error *
921 dump_symlink_target_path_to_file(FILE **outfile, const char *ondisk_path)
922 {
923 	const struct got_error *err = NULL;
924 	char target_path[PATH_MAX];
925 	ssize_t target_len;
926 	size_t n;
927 	FILE *f;
928 
929 	*outfile = NULL;
930 
931 	f = got_opentemp();
932 	if (f == NULL)
933 		return got_error_from_errno("got_opentemp");
934 	target_len = readlink(ondisk_path, target_path, sizeof(target_path));
935 	if (target_len == -1) {
936 		err = got_error_from_errno2("readlink", ondisk_path);
937 		goto done;
938 	}
939 	n = fwrite(target_path, 1, target_len, f);
940 	if (n != target_len) {
941 		err = got_ferror(f, GOT_ERR_IO);
942 		goto done;
943 	}
944 	if (fflush(f) == EOF) {
945 		err = got_error_from_errno("fflush");
946 		goto done;
947 	}
948 	if (fseek(f, 0L, SEEK_SET) == -1) {
949 		err = got_ferror(f, GOT_ERR_IO);
950 		goto done;
951 	}
952 done:
953 	if (err)
954 		fclose(f);
955 	else
956 		*outfile = f;
957 	return err;
958 }
959 
960 /*
961  * Perform a 3-way merge where blob_orig acts as the common ancestor,
962  * blob_deriv acts as the first derived version, and the file on disk
963  * acts as the second derived version.
964  */
965 static const struct got_error *
966 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
967     struct got_blob_object *blob_orig, const char *ondisk_path,
968     const char *path, uint16_t st_mode, const char *label_orig,
969     struct got_blob_object *blob_deriv,
970     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
971     got_worktree_checkout_cb progress_cb, void *progress_arg)
972 {
973 	const struct got_error *err = NULL;
974 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
975 	char *blob_orig_path = NULL;
976 	char *blob_deriv_path = NULL, *base_path = NULL, *id_str = NULL;
977 	char *label_deriv = NULL, *parent = NULL;
978 
979 	*local_changes_subsumed = 0;
980 
981 	err = got_path_dirname(&parent, ondisk_path);
982 	if (err)
983 		return err;
984 
985 	if (blob_orig) {
986 		if (asprintf(&base_path, "%s/got-merge-blob-orig",
987 		    parent) == -1) {
988 			err = got_error_from_errno("asprintf");
989 			base_path = NULL;
990 			goto done;
991 		}
992 
993 		err = got_opentemp_named(&blob_orig_path, &f_orig,
994 		    base_path, "");
995 		if (err)
996 			goto done;
997 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
998 		    blob_orig);
999 		if (err)
1000 			goto done;
1001 		free(base_path);
1002 	} else {
1003 		/*
1004 		 * No common ancestor exists. This is an "add vs add" conflict
1005 		 * and we simply use an empty ancestor file to make both files
1006 		 * appear in the merged result in their entirety.
1007 		 */
1008 		f_orig = got_opentemp();
1009 		if (f_orig == NULL) {
1010 			err = got_error_from_errno("got_opentemp");
1011 			goto done;
1012 		}
1013 	}
1014 
1015 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
1016 		err = got_error_from_errno("asprintf");
1017 		base_path = NULL;
1018 		goto done;
1019 	}
1020 
1021 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path, "");
1022 	if (err)
1023 		goto done;
1024 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
1025 	    blob_deriv);
1026 	if (err)
1027 		goto done;
1028 
1029 	err = got_object_id_str(&id_str, deriv_base_commit_id);
1030 	if (err)
1031 		goto done;
1032 	if (asprintf(&label_deriv, "%s: commit %s",
1033 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
1034 		err = got_error_from_errno("asprintf");
1035 		goto done;
1036 	}
1037 
1038 	/*
1039 	 * In order the run a 3-way merge with a symlink we copy the symlink's
1040 	 * target path into a temporary file and use that file with diff3.
1041 	 */
1042 	if (S_ISLNK(st_mode)) {
1043 		err = dump_symlink_target_path_to_file(&f_deriv2, ondisk_path);
1044 		if (err)
1045 			goto done;
1046 	} else {
1047 		int fd;
1048 		fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1049 		if (fd == -1) {
1050 			err = got_error_from_errno2("open", ondisk_path);
1051 			goto done;
1052 		}
1053 		f_deriv2 = fdopen(fd, "r");
1054 		if (f_deriv2 == NULL) {
1055 			err = got_error_from_errno2("fdopen", ondisk_path);
1056 			close(fd);
1057 			goto done;
1058 		}
1059 	}
1060 
1061 	err = merge_file(local_changes_subsumed, worktree, f_orig, f_deriv,
1062 	    f_deriv2, ondisk_path, path, st_mode, label_orig, label_deriv,
1063 	    NULL, GOT_DIFF_ALGORITHM_MYERS, repo, progress_cb, progress_arg);
1064 done:
1065 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
1066 		err = got_error_from_errno("fclose");
1067 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
1068 		err = got_error_from_errno("fclose");
1069 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
1070 		err = got_error_from_errno("fclose");
1071 	free(base_path);
1072 	if (blob_orig_path) {
1073 		unlink(blob_orig_path);
1074 		free(blob_orig_path);
1075 	}
1076 	if (blob_deriv_path) {
1077 		unlink(blob_deriv_path);
1078 		free(blob_deriv_path);
1079 	}
1080 	free(id_str);
1081 	free(label_deriv);
1082 	free(parent);
1083 	return err;
1084 }
1085 
1086 static const struct got_error *
1087 create_fileindex_entry(struct got_fileindex_entry **new_iep,
1088     struct got_fileindex *fileindex, struct got_object_id *base_commit_id,
1089     int wt_fd, const char *path, struct got_object_id *blob_id)
1090 {
1091 	const struct got_error *err = NULL;
1092 	struct got_fileindex_entry *new_ie;
1093 
1094 	*new_iep = NULL;
1095 
1096 	err = got_fileindex_entry_alloc(&new_ie, path);
1097 	if (err)
1098 		return err;
1099 
1100 	err = got_fileindex_entry_update(new_ie, wt_fd, path,
1101 	    blob_id->sha1, base_commit_id->sha1, 1);
1102 	if (err)
1103 		goto done;
1104 
1105 	err = got_fileindex_entry_add(fileindex, new_ie);
1106 done:
1107 	if (err)
1108 		got_fileindex_entry_free(new_ie);
1109 	else
1110 		*new_iep = new_ie;
1111 	return err;
1112 }
1113 
1114 static mode_t
1115 get_ondisk_perms(int executable, mode_t st_mode)
1116 {
1117 	mode_t xbits = S_IXUSR;
1118 
1119 	if (executable) {
1120 		/* Map read bits to execute bits. */
1121 		if (st_mode & S_IRGRP)
1122 			xbits |= S_IXGRP;
1123 		if (st_mode & S_IROTH)
1124 			xbits |= S_IXOTH;
1125 		return st_mode | xbits;
1126 	}
1127 
1128 	return st_mode;
1129 }
1130 
1131 static mode_t
1132 apply_umask(mode_t mode)
1133 {
1134 	mode_t um;
1135 
1136 	um = umask(000);
1137 	umask(um);
1138 	return mode & ~um;
1139 }
1140 
1141 /* forward declaration */
1142 static const struct got_error *
1143 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1144     const char *path, mode_t te_mode, mode_t st_mode,
1145     struct got_blob_object *blob, int restoring_missing_file,
1146     int reverting_versioned_file, int installing_bad_symlink,
1147     int path_is_unversioned, struct got_repository *repo,
1148     got_worktree_checkout_cb progress_cb, void *progress_arg);
1149 
1150 /*
1151  * This function assumes that the provided symlink target points at a
1152  * safe location in the work tree!
1153  */
1154 static const struct got_error *
1155 replace_existing_symlink(int *did_something, const char *ondisk_path,
1156     const char *target_path, size_t target_len)
1157 {
1158 	const struct got_error *err = NULL;
1159 	ssize_t elen;
1160 	char etarget[PATH_MAX];
1161 	int fd;
1162 
1163 	*did_something = 0;
1164 
1165 	/*
1166 	 * "Bad" symlinks (those pointing outside the work tree or into the
1167 	 * .got directory) are installed in the work tree as a regular file
1168 	 * which contains the bad symlink target path.
1169 	 * The new symlink target has already been checked for safety by our
1170 	 * caller. If we can successfully open a regular file then we simply
1171 	 * replace this file with a symlink below.
1172 	 */
1173 	fd = open(ondisk_path, O_RDWR | O_EXCL | O_NOFOLLOW | O_CLOEXEC);
1174 	if (fd == -1) {
1175 		if (!got_err_open_nofollow_on_symlink())
1176 			return got_error_from_errno2("open", ondisk_path);
1177 
1178 		/* We are updating an existing on-disk symlink. */
1179 		elen = readlink(ondisk_path, etarget, sizeof(etarget));
1180 		if (elen == -1)
1181 			return got_error_from_errno2("readlink", ondisk_path);
1182 
1183 		if (elen == target_len &&
1184 		    memcmp(etarget, target_path, target_len) == 0)
1185 			return NULL; /* nothing to do */
1186 	}
1187 
1188 	*did_something = 1;
1189 	err = update_symlink(ondisk_path, target_path, target_len);
1190 	if (fd != -1 && close(fd) == -1 && err == NULL)
1191 		err = got_error_from_errno2("close", ondisk_path);
1192 	return err;
1193 }
1194 
1195 static const struct got_error *
1196 is_bad_symlink_target(int *is_bad_symlink, const char *target_path,
1197     size_t target_len, const char *ondisk_path, const char *wtroot_path)
1198 {
1199 	const struct got_error *err = NULL;
1200 	char canonpath[PATH_MAX];
1201 	char *path_got = NULL;
1202 
1203 	*is_bad_symlink = 0;
1204 
1205 	if (target_len >= sizeof(canonpath)) {
1206 		*is_bad_symlink = 1;
1207 		return NULL;
1208 	}
1209 
1210 	/*
1211 	 * We do not use realpath(3) to resolve the symlink's target
1212 	 * path because we don't want to resolve symlinks recursively.
1213 	 * Instead we make the path absolute and then canonicalize it.
1214 	 * Relative symlink target lookup should begin at the directory
1215 	 * in which the blob object is being installed.
1216 	 */
1217 	if (!got_path_is_absolute(target_path)) {
1218 		char *abspath, *parent;
1219 		err = got_path_dirname(&parent, ondisk_path);
1220 		if (err)
1221 			return err;
1222 		if (asprintf(&abspath, "%s/%s",  parent, target_path) == -1) {
1223 			free(parent);
1224 			return got_error_from_errno("asprintf");
1225 		}
1226 		free(parent);
1227 		if (strlen(abspath) >= sizeof(canonpath)) {
1228 			err = got_error_path(abspath, GOT_ERR_BAD_PATH);
1229 			free(abspath);
1230 			return err;
1231 		}
1232 		err = got_canonpath(abspath, canonpath, sizeof(canonpath));
1233 		free(abspath);
1234 		if (err)
1235 			return err;
1236 	} else {
1237 		err = got_canonpath(target_path, canonpath, sizeof(canonpath));
1238 		if (err)
1239 			return err;
1240 	}
1241 
1242 	/* Only allow symlinks pointing at paths within the work tree. */
1243 	if (!got_path_is_child(canonpath, wtroot_path, strlen(wtroot_path))) {
1244 		*is_bad_symlink = 1;
1245 		return NULL;
1246 	}
1247 
1248 	/* Do not allow symlinks pointing into the .got directory. */
1249 	if (asprintf(&path_got, "%s/%s", wtroot_path,
1250 	    GOT_WORKTREE_GOT_DIR) == -1)
1251 		return got_error_from_errno("asprintf");
1252 	if (got_path_is_child(canonpath, path_got, strlen(path_got)))
1253 		*is_bad_symlink = 1;
1254 
1255 	free(path_got);
1256 	return NULL;
1257 }
1258 
1259 static const struct got_error *
1260 install_symlink(int *is_bad_symlink, struct got_worktree *worktree,
1261     const char *ondisk_path, const char *path, struct got_blob_object *blob,
1262     int restoring_missing_file, int reverting_versioned_file,
1263     int path_is_unversioned, int allow_bad_symlinks,
1264     struct got_repository *repo,
1265     got_worktree_checkout_cb progress_cb, void *progress_arg)
1266 {
1267 	const struct got_error *err = NULL;
1268 	char target_path[PATH_MAX];
1269 	size_t len, target_len = 0;
1270 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1271 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1272 
1273 	*is_bad_symlink = 0;
1274 
1275 	/*
1276 	 * Blob object content specifies the target path of the link.
1277 	 * If a symbolic link cannot be installed we instead create
1278 	 * a regular file which contains the link target path stored
1279 	 * in the blob object.
1280 	 */
1281 	do {
1282 		err = got_object_blob_read_block(&len, blob);
1283 		if (err)
1284 			return err;
1285 
1286 		if (len + target_len >= sizeof(target_path)) {
1287 			/* Path too long; install as a regular file. */
1288 			*is_bad_symlink = 1;
1289 			got_object_blob_rewind(blob);
1290 			return install_blob(worktree, ondisk_path, path,
1291 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1292 			    restoring_missing_file, reverting_versioned_file,
1293 			    1, path_is_unversioned, repo, progress_cb,
1294 			    progress_arg);
1295 		}
1296 		if (len > 0) {
1297 			/* Skip blob object header first time around. */
1298 			memcpy(target_path + target_len, buf + hdrlen,
1299 			    len - hdrlen);
1300 			target_len += len - hdrlen;
1301 			hdrlen = 0;
1302 		}
1303 	} while (len != 0);
1304 	target_path[target_len] = '\0';
1305 
1306 	err = is_bad_symlink_target(is_bad_symlink, target_path, target_len,
1307 	    ondisk_path, worktree->root_path);
1308 	if (err)
1309 		return err;
1310 
1311 	if (*is_bad_symlink && !allow_bad_symlinks) {
1312 		/* install as a regular file */
1313 		got_object_blob_rewind(blob);
1314 		err = install_blob(worktree, ondisk_path, path,
1315 		    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1316 		    restoring_missing_file, reverting_versioned_file, 1,
1317 		    path_is_unversioned, repo, progress_cb, progress_arg);
1318 		return err;
1319 	}
1320 
1321 	if (symlink(target_path, ondisk_path) == -1) {
1322 		if (errno == EEXIST) {
1323 			int symlink_replaced;
1324 			if (path_is_unversioned) {
1325 				err = (*progress_cb)(progress_arg,
1326 				    GOT_STATUS_UNVERSIONED, path);
1327 				return err;
1328 			}
1329 			err = replace_existing_symlink(&symlink_replaced,
1330 			    ondisk_path, target_path, target_len);
1331 			if (err)
1332 				return err;
1333 			if (progress_cb) {
1334 				if (symlink_replaced) {
1335 					err = (*progress_cb)(progress_arg,
1336 					    reverting_versioned_file ?
1337 					    GOT_STATUS_REVERT :
1338 					    GOT_STATUS_UPDATE, path);
1339 				} else {
1340 					err = (*progress_cb)(progress_arg,
1341 					    GOT_STATUS_EXISTS, path);
1342 				}
1343 			}
1344 			return err; /* Nothing else to do. */
1345 		}
1346 
1347 		if (errno == ENOENT) {
1348 			char *parent;
1349 			err = got_path_dirname(&parent, ondisk_path);
1350 			if (err)
1351 				return err;
1352 			err = add_dir_on_disk(worktree, parent);
1353 			free(parent);
1354 			if (err)
1355 				return err;
1356 			/*
1357 			 * Retry, and fall through to error handling
1358 			 * below if this second attempt fails.
1359 			 */
1360 			if (symlink(target_path, ondisk_path) != -1) {
1361 				err = NULL; /* success */
1362 				return err;
1363 			}
1364 		}
1365 
1366 		/* Handle errors from first or second creation attempt. */
1367 		if (errno == ENAMETOOLONG) {
1368 			/* bad target path; install as a regular file */
1369 			*is_bad_symlink = 1;
1370 			got_object_blob_rewind(blob);
1371 			err = install_blob(worktree, ondisk_path, path,
1372 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1373 			    restoring_missing_file, reverting_versioned_file, 1,
1374 			    path_is_unversioned, repo,
1375 			    progress_cb, progress_arg);
1376 		} else if (errno == ENOTDIR) {
1377 			err = got_error_path(ondisk_path,
1378 			    GOT_ERR_FILE_OBSTRUCTED);
1379 		} else {
1380 			err = got_error_from_errno3("symlink",
1381 			    target_path, ondisk_path);
1382 		}
1383 	} else if (progress_cb)
1384 		err = (*progress_cb)(progress_arg, reverting_versioned_file ?
1385 		    GOT_STATUS_REVERT : GOT_STATUS_ADD, path);
1386 	return err;
1387 }
1388 
1389 static const struct got_error *
1390 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1391     const char *path, mode_t te_mode, mode_t st_mode,
1392     struct got_blob_object *blob, int restoring_missing_file,
1393     int reverting_versioned_file, int installing_bad_symlink,
1394     int path_is_unversioned, struct got_repository *repo,
1395     got_worktree_checkout_cb progress_cb, void *progress_arg)
1396 {
1397 	const struct got_error *err = NULL;
1398 	int fd = -1;
1399 	size_t len, hdrlen;
1400 	int update = 0;
1401 	char *tmppath = NULL;
1402 	mode_t mode;
1403 
1404 	mode = get_ondisk_perms(te_mode & S_IXUSR, GOT_DEFAULT_FILE_MODE);
1405 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW |
1406 	    O_CLOEXEC, mode);
1407 	if (fd == -1) {
1408 		if (errno == ENOENT) {
1409 			char *parent;
1410 			err = got_path_dirname(&parent, path);
1411 			if (err)
1412 				return err;
1413 			err = add_dir_on_disk(worktree, parent);
1414 			free(parent);
1415 			if (err)
1416 				return err;
1417 			fd = open(ondisk_path,
1418 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW | O_CLOEXEC,
1419 			    mode);
1420 			if (fd == -1)
1421 				return got_error_from_errno2("open",
1422 				    ondisk_path);
1423 		} else if (errno == EEXIST) {
1424 			if (path_is_unversioned) {
1425 				err = (*progress_cb)(progress_arg,
1426 				    GOT_STATUS_UNVERSIONED, path);
1427 				goto done;
1428 			}
1429 			if (!(S_ISLNK(st_mode) && S_ISREG(te_mode)) &&
1430 			    !S_ISREG(st_mode) && !installing_bad_symlink) {
1431 				/* TODO file is obstructed; do something */
1432 				err = got_error_path(ondisk_path,
1433 				    GOT_ERR_FILE_OBSTRUCTED);
1434 				goto done;
1435 			} else {
1436 				err = got_opentemp_named_fd(&tmppath, &fd,
1437 				    ondisk_path, "");
1438 				if (err)
1439 					goto done;
1440 				update = 1;
1441 
1442 				if (fchmod(fd, apply_umask(mode)) == -1) {
1443 					err = got_error_from_errno2("fchmod",
1444 					    tmppath);
1445 					goto done;
1446 				}
1447 			}
1448 		} else
1449 			return got_error_from_errno2("open", ondisk_path);
1450 	}
1451 
1452 	if (progress_cb) {
1453 		if (restoring_missing_file)
1454 			err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING,
1455 			    path);
1456 		else if (reverting_versioned_file)
1457 			err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT,
1458 			    path);
1459 		else
1460 			err = (*progress_cb)(progress_arg,
1461 			    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
1462 		if (err)
1463 			goto done;
1464 	}
1465 
1466 	hdrlen = got_object_blob_get_hdrlen(blob);
1467 	do {
1468 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
1469 		err = got_object_blob_read_block(&len, blob);
1470 		if (err)
1471 			break;
1472 		if (len > 0) {
1473 			/* Skip blob object header first time around. */
1474 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
1475 			if (outlen == -1) {
1476 				err = got_error_from_errno("write");
1477 				goto done;
1478 			} else if (outlen != len - hdrlen) {
1479 				err = got_error(GOT_ERR_IO);
1480 				goto done;
1481 			}
1482 			hdrlen = 0;
1483 		}
1484 	} while (len != 0);
1485 
1486 	if (fsync(fd) != 0) {
1487 		err = got_error_from_errno("fsync");
1488 		goto done;
1489 	}
1490 
1491 	if (update) {
1492 		if (S_ISLNK(st_mode) && unlink(ondisk_path) == -1) {
1493 			err = got_error_from_errno2("unlink", ondisk_path);
1494 			goto done;
1495 		}
1496 		if (rename(tmppath, ondisk_path) != 0) {
1497 			err = got_error_from_errno3("rename", tmppath,
1498 			    ondisk_path);
1499 			goto done;
1500 		}
1501 		free(tmppath);
1502 		tmppath = NULL;
1503 	}
1504 
1505 done:
1506 	if (fd != -1 && close(fd) == -1 && err == NULL)
1507 		err = got_error_from_errno("close");
1508 	if (tmppath != NULL && unlink(tmppath) == -1 && err == NULL)
1509 		err = got_error_from_errno2("unlink", tmppath);
1510 	free(tmppath);
1511 	return err;
1512 }
1513 
1514 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
1515 static const struct got_error *
1516 get_modified_file_content_status(unsigned char *status, FILE *f)
1517 {
1518 	const struct got_error *err = NULL;
1519 	const char *markers[3] = {
1520 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
1521 		GOT_DIFF_CONFLICT_MARKER_SEP,
1522 		GOT_DIFF_CONFLICT_MARKER_END
1523 	};
1524 	int i = 0;
1525 	char *line = NULL;
1526 	size_t linesize = 0;
1527 	ssize_t linelen;
1528 
1529 	while (*status == GOT_STATUS_MODIFY) {
1530 		linelen = getline(&line, &linesize, f);
1531 		if (linelen == -1) {
1532 			if (feof(f))
1533 				break;
1534 			err = got_ferror(f, GOT_ERR_IO);
1535 			break;
1536 		}
1537 
1538 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1539 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1540 			    == 0)
1541 				*status = GOT_STATUS_CONFLICT;
1542 			else
1543 				i++;
1544 		}
1545 	}
1546 	free(line);
1547 
1548 	return err;
1549 }
1550 
1551 static int
1552 xbit_differs(struct got_fileindex_entry *ie, uint16_t st_mode)
1553 {
1554 	mode_t ie_mode = got_fileindex_perms_to_st(ie);
1555 	return ((ie_mode & S_IXUSR) != (st_mode & S_IXUSR));
1556 }
1557 
1558 static int
1559 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1560 {
1561 	return !(ie->ctime_sec == sb->st_ctim.tv_sec &&
1562 	    ie->ctime_nsec == sb->st_ctim.tv_nsec &&
1563 	    ie->mtime_sec == sb->st_mtim.tv_sec &&
1564 	    ie->mtime_nsec == sb->st_mtim.tv_nsec &&
1565 	    ie->size == (sb->st_size & 0xffffffff) &&
1566 	    !xbit_differs(ie, sb->st_mode));
1567 }
1568 
1569 static unsigned char
1570 get_staged_status(struct got_fileindex_entry *ie)
1571 {
1572 	switch (got_fileindex_entry_stage_get(ie)) {
1573 	case GOT_FILEIDX_STAGE_ADD:
1574 		return GOT_STATUS_ADD;
1575 	case GOT_FILEIDX_STAGE_DELETE:
1576 		return GOT_STATUS_DELETE;
1577 	case GOT_FILEIDX_STAGE_MODIFY:
1578 		return GOT_STATUS_MODIFY;
1579 	default:
1580 		return GOT_STATUS_NO_CHANGE;
1581 	}
1582 }
1583 
1584 static const struct got_error *
1585 get_symlink_modification_status(unsigned char *status,
1586     struct got_fileindex_entry *ie, const char *abspath,
1587     int dirfd, const char *de_name, struct got_blob_object *blob)
1588 {
1589 	const struct got_error *err = NULL;
1590 	char target_path[PATH_MAX];
1591 	char etarget[PATH_MAX];
1592 	ssize_t elen;
1593 	size_t len, target_len = 0;
1594 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1595 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1596 
1597 	*status = GOT_STATUS_NO_CHANGE;
1598 
1599 	/* Blob object content specifies the target path of the link. */
1600 	do {
1601 		err = got_object_blob_read_block(&len, blob);
1602 		if (err)
1603 			return err;
1604 		if (len + target_len >= sizeof(target_path)) {
1605 			/*
1606 			 * Should not happen. The blob contents were OK
1607 			 * when this symlink was installed.
1608 			 */
1609 			return got_error(GOT_ERR_NO_SPACE);
1610 		}
1611 		if (len > 0) {
1612 			/* Skip blob object header first time around. */
1613 			memcpy(target_path + target_len, buf + hdrlen,
1614 			    len - hdrlen);
1615 			target_len += len - hdrlen;
1616 			hdrlen = 0;
1617 		}
1618 	} while (len != 0);
1619 	target_path[target_len] = '\0';
1620 
1621 	if (dirfd != -1) {
1622 		elen = readlinkat(dirfd, de_name, etarget, sizeof(etarget));
1623 		if (elen == -1)
1624 			return got_error_from_errno2("readlinkat", abspath);
1625 	} else {
1626 		elen = readlink(abspath, etarget, sizeof(etarget));
1627 		if (elen == -1)
1628 			return got_error_from_errno2("readlink", abspath);
1629 	}
1630 
1631 	if (elen != target_len || memcmp(etarget, target_path, target_len) != 0)
1632 		*status = GOT_STATUS_MODIFY;
1633 
1634 	return NULL;
1635 }
1636 
1637 static const struct got_error *
1638 get_file_status(unsigned char *status, struct stat *sb,
1639     struct got_fileindex_entry *ie, const char *abspath,
1640     int dirfd, const char *de_name, struct got_repository *repo)
1641 {
1642 	const struct got_error *err = NULL;
1643 	struct got_object_id id;
1644 	size_t hdrlen;
1645 	int fd = -1, fd1 = -1;
1646 	FILE *f = NULL;
1647 	uint8_t fbuf[8192];
1648 	struct got_blob_object *blob = NULL;
1649 	size_t flen, blen;
1650 	unsigned char staged_status = get_staged_status(ie);
1651 
1652 	*status = GOT_STATUS_NO_CHANGE;
1653 	memset(sb, 0, sizeof(*sb));
1654 
1655 	/*
1656 	 * Whenever the caller provides a directory descriptor and a
1657 	 * directory entry name for the file, use them! This prevents
1658 	 * race conditions if filesystem paths change beneath our feet.
1659 	 */
1660 	if (dirfd != -1) {
1661 		if (fstatat(dirfd, de_name, sb, AT_SYMLINK_NOFOLLOW) == -1) {
1662 			if (errno == ENOENT) {
1663 				if (got_fileindex_entry_has_file_on_disk(ie))
1664 					*status = GOT_STATUS_MISSING;
1665 				else
1666 					*status = GOT_STATUS_DELETE;
1667 				goto done;
1668 			}
1669 			err = got_error_from_errno2("fstatat", abspath);
1670 			goto done;
1671 		}
1672 	} else {
1673 		fd = open(abspath, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1674 		if (fd == -1 && errno != ENOENT &&
1675 		    !got_err_open_nofollow_on_symlink())
1676 			return got_error_from_errno2("open", abspath);
1677 		else if (fd == -1 && got_err_open_nofollow_on_symlink()) {
1678 			if (lstat(abspath, sb) == -1)
1679 				return got_error_from_errno2("lstat", abspath);
1680 		} else if (fd == -1 || fstat(fd, sb) == -1) {
1681 			if (errno == ENOENT) {
1682 				if (got_fileindex_entry_has_file_on_disk(ie))
1683 					*status = GOT_STATUS_MISSING;
1684 				else
1685 					*status = GOT_STATUS_DELETE;
1686 				goto done;
1687 			}
1688 			err = got_error_from_errno2("fstat", abspath);
1689 			goto done;
1690 		}
1691 	}
1692 
1693 	if (!S_ISREG(sb->st_mode) && !S_ISLNK(sb->st_mode)) {
1694 		*status = GOT_STATUS_OBSTRUCTED;
1695 		goto done;
1696 	}
1697 
1698 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1699 		*status = GOT_STATUS_DELETE;
1700 		goto done;
1701 	} else if (!got_fileindex_entry_has_blob(ie) &&
1702 	    staged_status != GOT_STATUS_ADD) {
1703 		*status = GOT_STATUS_ADD;
1704 		goto done;
1705 	}
1706 
1707 	if (!stat_info_differs(ie, sb))
1708 		goto done;
1709 
1710 	if (S_ISLNK(sb->st_mode) &&
1711 	    got_fileindex_entry_filetype_get(ie) != GOT_FILEIDX_MODE_SYMLINK) {
1712 		*status = GOT_STATUS_MODIFY;
1713 		goto done;
1714 	}
1715 
1716 	if (staged_status == GOT_STATUS_MODIFY ||
1717 	    staged_status == GOT_STATUS_ADD)
1718 		memcpy(id.sha1, ie->staged_blob_sha1, sizeof(id.sha1));
1719 	else
1720 		memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1721 
1722 	fd1 = got_opentempfd();
1723 	if (fd1 == -1) {
1724 		err = got_error_from_errno("got_opentempfd");
1725 		goto done;
1726 	}
1727 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf), fd1);
1728 	if (err)
1729 		goto done;
1730 
1731 	if (S_ISLNK(sb->st_mode)) {
1732 		err = get_symlink_modification_status(status, ie,
1733 		    abspath, dirfd, de_name, blob);
1734 		goto done;
1735 	}
1736 
1737 	if (dirfd != -1) {
1738 		fd = openat(dirfd, de_name, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1739 		if (fd == -1) {
1740 			err = got_error_from_errno2("openat", abspath);
1741 			goto done;
1742 		}
1743 	}
1744 
1745 	f = fdopen(fd, "r");
1746 	if (f == NULL) {
1747 		err = got_error_from_errno2("fdopen", abspath);
1748 		goto done;
1749 	}
1750 	fd = -1;
1751 	hdrlen = got_object_blob_get_hdrlen(blob);
1752 	for (;;) {
1753 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1754 		err = got_object_blob_read_block(&blen, blob);
1755 		if (err)
1756 			goto done;
1757 		/* Skip length of blob object header first time around. */
1758 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1759 		if (flen == 0 && ferror(f)) {
1760 			err = got_error_from_errno("fread");
1761 			goto done;
1762 		}
1763 		if (blen - hdrlen == 0) {
1764 			if (flen != 0)
1765 				*status = GOT_STATUS_MODIFY;
1766 			break;
1767 		} else if (flen == 0) {
1768 			if (blen - hdrlen != 0)
1769 				*status = GOT_STATUS_MODIFY;
1770 			break;
1771 		} else if (blen - hdrlen == flen) {
1772 			/* Skip blob object header first time around. */
1773 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1774 				*status = GOT_STATUS_MODIFY;
1775 				break;
1776 			}
1777 		} else {
1778 			*status = GOT_STATUS_MODIFY;
1779 			break;
1780 		}
1781 		hdrlen = 0;
1782 	}
1783 
1784 	if (*status == GOT_STATUS_MODIFY) {
1785 		rewind(f);
1786 		err = get_modified_file_content_status(status, f);
1787 	} else if (xbit_differs(ie, sb->st_mode))
1788 		*status = GOT_STATUS_MODE_CHANGE;
1789 done:
1790 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
1791 		err = got_error_from_errno("close");
1792 	if (blob)
1793 		got_object_blob_close(blob);
1794 	if (f != NULL && fclose(f) == EOF && err == NULL)
1795 		err = got_error_from_errno2("fclose", abspath);
1796 	if (fd != -1 && close(fd) == -1 && err == NULL)
1797 		err = got_error_from_errno2("close", abspath);
1798 	return err;
1799 }
1800 
1801 /*
1802  * Update timestamps in the file index if a file is unmodified and
1803  * we had to run a full content comparison to find out.
1804  */
1805 static const struct got_error *
1806 sync_timestamps(int wt_fd, const char *path, unsigned char status,
1807     struct got_fileindex_entry *ie, struct stat *sb)
1808 {
1809 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1810 		return got_fileindex_entry_update(ie, wt_fd, path,
1811 		    ie->blob_sha1, ie->commit_sha1, 1);
1812 
1813 	return NULL;
1814 }
1815 
1816 static const struct got_error *
1817 update_blob(struct got_worktree *worktree,
1818     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1819     struct got_tree_entry *te, const char *path,
1820     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1821     void *progress_arg)
1822 {
1823 	const struct got_error *err = NULL;
1824 	struct got_blob_object *blob = NULL;
1825 	char *ondisk_path = NULL;
1826 	unsigned char status = GOT_STATUS_NO_CHANGE;
1827 	struct stat sb;
1828 	int fd1 = -1, fd2 = -1;
1829 
1830 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1831 		return got_error_from_errno("asprintf");
1832 
1833 	if (ie) {
1834 		if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE) {
1835 			err = got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1836 			goto done;
1837 		}
1838 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
1839 		    repo);
1840 		if (err)
1841 			goto done;
1842 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1843 			sb.st_mode = got_fileindex_perms_to_st(ie);
1844 	} else {
1845 		if (stat(ondisk_path, &sb) == -1) {
1846 			if (errno != ENOENT) {
1847 				err = got_error_from_errno2("stat",
1848 				    ondisk_path);
1849 				goto done;
1850 			}
1851 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1852 			status = GOT_STATUS_UNVERSIONED;
1853 		} else {
1854 			if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
1855 				status = GOT_STATUS_UNVERSIONED;
1856 			else
1857 				status = GOT_STATUS_OBSTRUCTED;
1858 		}
1859 	}
1860 
1861 	if (status == GOT_STATUS_OBSTRUCTED) {
1862 		if (ie)
1863 			got_fileindex_entry_mark_skipped(ie);
1864 		err = (*progress_cb)(progress_arg, status, path);
1865 		goto done;
1866 	}
1867 	if (status == GOT_STATUS_CONFLICT) {
1868 		if (ie)
1869 			got_fileindex_entry_mark_skipped(ie);
1870 		err = (*progress_cb)(progress_arg, GOT_STATUS_CANNOT_UPDATE,
1871 		    path);
1872 		goto done;
1873 	}
1874 
1875 	if (ie && status != GOT_STATUS_MISSING && S_ISREG(sb.st_mode) &&
1876 	    (S_ISLNK(te->mode) ||
1877 	    (te->mode & S_IXUSR) == (sb.st_mode & S_IXUSR))) {
1878 		/*
1879 		 * This is a regular file or an installed bad symlink.
1880 		 * If the file index indicates that this file is already
1881 		 * up-to-date with respect to the repository we can skip
1882 		 * updating contents of this file.
1883 		 */
1884 		if (got_fileindex_entry_has_commit(ie) &&
1885 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1886 		    SHA1_DIGEST_LENGTH) == 0) {
1887 			/* Same commit. */
1888 			err = sync_timestamps(worktree->root_fd,
1889 			    path, status, ie, &sb);
1890 			if (err)
1891 				goto done;
1892 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1893 			    path);
1894 			goto done;
1895 		}
1896 		if (got_fileindex_entry_has_blob(ie) &&
1897 		    memcmp(ie->blob_sha1, te->id.sha1,
1898 		    SHA1_DIGEST_LENGTH) == 0) {
1899 			/* Different commit but the same blob. */
1900 			err = sync_timestamps(worktree->root_fd,
1901 			    path, status, ie, &sb);
1902 			if (err)
1903 				goto done;
1904 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1905 			    path);
1906 			goto done;
1907 		}
1908 	}
1909 
1910 	fd1 = got_opentempfd();
1911 	if (fd1 == -1) {
1912 		err = got_error_from_errno("got_opentempfd");
1913 		goto done;
1914 	}
1915 	err = got_object_open_as_blob(&blob, repo, &te->id, 8192, fd1);
1916 	if (err)
1917 		goto done;
1918 
1919 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1920 		int update_timestamps;
1921 		struct got_blob_object *blob2 = NULL;
1922 		char *label_orig = NULL;
1923 		if (got_fileindex_entry_has_blob(ie)) {
1924 			fd2 = got_opentempfd();
1925 			if (fd2 == -1) {
1926 				err = got_error_from_errno("got_opentempfd");
1927 				goto done;
1928 			}
1929 			struct got_object_id id2;
1930 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1931 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192,
1932 			    fd2);
1933 			if (err)
1934 				goto done;
1935 		}
1936 		if (got_fileindex_entry_has_commit(ie)) {
1937 			char id_str[SHA1_DIGEST_STRING_LENGTH];
1938 			if (got_sha1_digest_to_str(ie->commit_sha1, id_str,
1939 			    sizeof(id_str)) == NULL) {
1940 				err = got_error_path(id_str,
1941 				    GOT_ERR_BAD_OBJ_ID_STR);
1942 				goto done;
1943 			}
1944 			if (asprintf(&label_orig, "%s: commit %s",
1945 			    GOT_MERGE_LABEL_BASE, id_str) == -1) {
1946 				err = got_error_from_errno("asprintf");
1947 				goto done;
1948 			}
1949 		}
1950 		if (S_ISLNK(te->mode) && S_ISLNK(sb.st_mode)) {
1951 			char *link_target;
1952 			err = got_object_blob_read_to_str(&link_target, blob);
1953 			if (err)
1954 				goto done;
1955 			err = merge_symlink(worktree, blob2, ondisk_path, path,
1956 			    label_orig, link_target, worktree->base_commit_id,
1957 			    repo, progress_cb, progress_arg);
1958 			free(link_target);
1959 		} else {
1960 			err = merge_blob(&update_timestamps, worktree, blob2,
1961 			    ondisk_path, path, sb.st_mode, label_orig, blob,
1962 			    worktree->base_commit_id, repo,
1963 			    progress_cb, progress_arg);
1964 		}
1965 		free(label_orig);
1966 		if (fd2 != -1 && close(fd2) == -1 && err == NULL) {
1967 			err = got_error_from_errno("close");
1968 			goto done;
1969 		}
1970 		if (blob2)
1971 			got_object_blob_close(blob2);
1972 		if (err)
1973 			goto done;
1974 		/*
1975 		 * Do not update timestamps of files with local changes.
1976 		 * Otherwise, a future status walk would treat them as
1977 		 * unmodified files again.
1978 		 */
1979 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
1980 		    blob->id.sha1, worktree->base_commit_id->sha1,
1981 		    update_timestamps);
1982 	} else if (status == GOT_STATUS_MODE_CHANGE) {
1983 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
1984 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
1985 	} else if (status == GOT_STATUS_DELETE) {
1986 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1987 		if (err)
1988 			goto done;
1989 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
1990 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
1991 		if (err)
1992 			goto done;
1993 	} else {
1994 		int is_bad_symlink = 0;
1995 		if (S_ISLNK(te->mode)) {
1996 			err = install_symlink(&is_bad_symlink, worktree,
1997 			    ondisk_path, path, blob,
1998 			    status == GOT_STATUS_MISSING, 0,
1999 			    status == GOT_STATUS_UNVERSIONED, 0,
2000 			    repo, progress_cb, progress_arg);
2001 		} else {
2002 			err = install_blob(worktree, ondisk_path, path,
2003 			    te->mode, sb.st_mode, blob,
2004 			    status == GOT_STATUS_MISSING, 0, 0,
2005 			    status == GOT_STATUS_UNVERSIONED, repo,
2006 			    progress_cb, progress_arg);
2007 		}
2008 		if (err)
2009 			goto done;
2010 
2011 		if (ie) {
2012 			err = got_fileindex_entry_update(ie,
2013 			    worktree->root_fd, path, blob->id.sha1,
2014 			    worktree->base_commit_id->sha1, 1);
2015 		} else {
2016 			err = create_fileindex_entry(&ie, fileindex,
2017 			    worktree->base_commit_id, worktree->root_fd, path,
2018 			    &blob->id);
2019 		}
2020 		if (err)
2021 			goto done;
2022 
2023 		if (is_bad_symlink) {
2024 			got_fileindex_entry_filetype_set(ie,
2025 			    GOT_FILEIDX_MODE_BAD_SYMLINK);
2026 		}
2027 	}
2028 
2029 	if (fd1 != -1 && close(fd1) == -1 && err == NULL) {
2030 		err = got_error_from_errno("close");
2031 		goto done;
2032 	}
2033 	got_object_blob_close(blob);
2034 done:
2035 	free(ondisk_path);
2036 	return err;
2037 }
2038 
2039 static const struct got_error *
2040 remove_ondisk_file(const char *root_path, const char *path)
2041 {
2042 	const struct got_error *err = NULL;
2043 	char *ondisk_path = NULL, *parent = NULL;
2044 
2045 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
2046 		return got_error_from_errno("asprintf");
2047 
2048 	if (unlink(ondisk_path) == -1) {
2049 		if (errno != ENOENT)
2050 			err = got_error_from_errno2("unlink", ondisk_path);
2051 	} else {
2052 		size_t root_len = strlen(root_path);
2053 		err = got_path_dirname(&parent, ondisk_path);
2054 		if (err)
2055 			goto done;
2056 		while (got_path_cmp(parent, root_path,
2057 		    strlen(parent), root_len) != 0) {
2058 			free(ondisk_path);
2059 			ondisk_path = parent;
2060 			parent = NULL;
2061 			if (rmdir(ondisk_path) == -1) {
2062 				if (errno != ENOTEMPTY)
2063 					err = got_error_from_errno2("rmdir",
2064 					    ondisk_path);
2065 				break;
2066 			}
2067 			err = got_path_dirname(&parent, ondisk_path);
2068 			if (err)
2069 				break;
2070 		}
2071 	}
2072 done:
2073 	free(ondisk_path);
2074 	free(parent);
2075 	return err;
2076 }
2077 
2078 static const struct got_error *
2079 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
2080     struct got_fileindex_entry *ie, struct got_repository *repo,
2081     got_worktree_checkout_cb progress_cb, void *progress_arg)
2082 {
2083 	const struct got_error *err = NULL;
2084 	unsigned char status;
2085 	struct stat sb;
2086 	char *ondisk_path;
2087 
2088 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
2089 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
2090 
2091 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
2092 	    == -1)
2093 		return got_error_from_errno("asprintf");
2094 
2095 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, repo);
2096 	if (err)
2097 		goto done;
2098 
2099 	if (S_ISLNK(sb.st_mode) && status != GOT_STATUS_NO_CHANGE) {
2100 		char ondisk_target[PATH_MAX];
2101 		ssize_t ondisk_len = readlink(ondisk_path, ondisk_target,
2102 		    sizeof(ondisk_target));
2103 		if (ondisk_len == -1) {
2104 			err = got_error_from_errno2("readlink", ondisk_path);
2105 			goto done;
2106 		}
2107 		ondisk_target[ondisk_len] = '\0';
2108 		err = install_symlink_conflict(NULL, worktree->base_commit_id,
2109 		    NULL, NULL, /* XXX pass common ancestor info? */
2110 		    ondisk_target, ondisk_path);
2111 		if (err)
2112 			goto done;
2113 		err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
2114 		    ie->path);
2115 		goto done;
2116 	}
2117 
2118 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
2119 	    status == GOT_STATUS_ADD) {
2120 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
2121 		if (err)
2122 			goto done;
2123 		/*
2124 		 * Preserve the working file and change the deleted blob's
2125 		 * entry into a schedule-add entry.
2126 		 */
2127 		err = got_fileindex_entry_update(ie, worktree->root_fd,
2128 		    ie->path, NULL, NULL, 0);
2129 	} else {
2130 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
2131 		if (err)
2132 			goto done;
2133 		if (status == GOT_STATUS_NO_CHANGE) {
2134 			err = remove_ondisk_file(worktree->root_path, ie->path);
2135 			if (err)
2136 				goto done;
2137 		}
2138 		got_fileindex_entry_remove(fileindex, ie);
2139 	}
2140 done:
2141 	free(ondisk_path);
2142 	return err;
2143 }
2144 
2145 struct diff_cb_arg {
2146     struct got_fileindex *fileindex;
2147     struct got_worktree *worktree;
2148     struct got_repository *repo;
2149     got_worktree_checkout_cb progress_cb;
2150     void *progress_arg;
2151     got_cancel_cb cancel_cb;
2152     void *cancel_arg;
2153 };
2154 
2155 static const struct got_error *
2156 diff_old_new(void *arg, struct got_fileindex_entry *ie,
2157     struct got_tree_entry *te, const char *parent_path)
2158 {
2159 	struct diff_cb_arg *a = arg;
2160 
2161 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2162 		return got_error(GOT_ERR_CANCELLED);
2163 
2164 	return update_blob(a->worktree, a->fileindex, ie, te,
2165 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
2166 }
2167 
2168 static const struct got_error *
2169 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2170 {
2171 	struct diff_cb_arg *a = arg;
2172 
2173 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2174 		return got_error(GOT_ERR_CANCELLED);
2175 
2176 	return delete_blob(a->worktree, a->fileindex, ie,
2177 	    a->repo, a->progress_cb, a->progress_arg);
2178 }
2179 
2180 static const struct got_error *
2181 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
2182 {
2183 	struct diff_cb_arg *a = arg;
2184 	const struct got_error *err;
2185 	char *path;
2186 
2187 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2188 		return got_error(GOT_ERR_CANCELLED);
2189 
2190 	if (got_object_tree_entry_is_submodule(te))
2191 		return NULL;
2192 
2193 	if (asprintf(&path, "%s%s%s", parent_path,
2194 	    parent_path[0] ? "/" : "", te->name)
2195 	    == -1)
2196 		return got_error_from_errno("asprintf");
2197 
2198 	if (S_ISDIR(te->mode))
2199 		err = add_dir_on_disk(a->worktree, path);
2200 	else
2201 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
2202 		    a->repo, a->progress_cb, a->progress_arg);
2203 
2204 	free(path);
2205 	return err;
2206 }
2207 
2208 const struct got_error *
2209 got_worktree_get_uuid(char **uuidstr, struct got_worktree *worktree)
2210 {
2211 	uint32_t uuid_status;
2212 
2213 	uuid_to_string(&worktree->uuid, uuidstr, &uuid_status);
2214 	if (uuid_status != uuid_s_ok) {
2215 		*uuidstr = NULL;
2216 		return got_error_uuid(uuid_status, "uuid_to_string");
2217 	}
2218 
2219 	return NULL;
2220 }
2221 
2222 static const struct got_error *
2223 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
2224 {
2225 	const struct got_error *err = NULL;
2226 	char *uuidstr = NULL;
2227 
2228 	*refname = NULL;
2229 
2230 	err = got_worktree_get_uuid(&uuidstr, worktree);
2231 	if (err)
2232 		return err;
2233 
2234 	if (asprintf(refname, "%s-%s", prefix, uuidstr) == -1) {
2235 		err = got_error_from_errno("asprintf");
2236 		*refname = NULL;
2237 	}
2238 	free(uuidstr);
2239 	return err;
2240 }
2241 
2242 const struct got_error *
2243 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
2244 {
2245 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
2246 }
2247 
2248 static const struct got_error *
2249 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
2250 {
2251 	return get_ref_name(refname, worktree,
2252 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
2253 }
2254 
2255 static const struct got_error *
2256 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
2257 {
2258 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
2259 }
2260 
2261 static const struct got_error *
2262 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
2263 {
2264 	return get_ref_name(refname, worktree,
2265 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
2266 }
2267 
2268 static const struct got_error *
2269 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
2270 {
2271 	return get_ref_name(refname, worktree,
2272 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
2273 }
2274 
2275 static const struct got_error *
2276 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
2277 {
2278 	return get_ref_name(refname, worktree,
2279 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
2280 }
2281 
2282 static const struct got_error *
2283 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
2284 {
2285 	return get_ref_name(refname, worktree,
2286 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
2287 }
2288 
2289 static const struct got_error *
2290 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
2291 {
2292 	return get_ref_name(refname, worktree,
2293 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
2294 }
2295 
2296 static const struct got_error *
2297 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
2298 {
2299 	return get_ref_name(refname, worktree,
2300 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
2301 }
2302 
2303 const struct got_error *
2304 got_worktree_get_histedit_script_path(char **path,
2305     struct got_worktree *worktree)
2306 {
2307 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
2308 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
2309 		*path = NULL;
2310 		return got_error_from_errno("asprintf");
2311 	}
2312 	return NULL;
2313 }
2314 
2315 static const struct got_error *
2316 get_merge_branch_ref_name(char **refname, struct got_worktree *worktree)
2317 {
2318 	return get_ref_name(refname, worktree,
2319 	    GOT_WORKTREE_MERGE_BRANCH_REF_PREFIX);
2320 }
2321 
2322 static const struct got_error *
2323 get_merge_commit_ref_name(char **refname, struct got_worktree *worktree)
2324 {
2325 	return get_ref_name(refname, worktree,
2326 	    GOT_WORKTREE_MERGE_COMMIT_REF_PREFIX);
2327 }
2328 
2329 /*
2330  * Prevent Git's garbage collector from deleting our base commit by
2331  * setting a reference to our base commit's ID.
2332  */
2333 static const struct got_error *
2334 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
2335 {
2336 	const struct got_error *err = NULL;
2337 	struct got_reference *ref = NULL;
2338 	char *refname;
2339 
2340 	err = got_worktree_get_base_ref_name(&refname, worktree);
2341 	if (err)
2342 		return err;
2343 
2344 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
2345 	if (err)
2346 		goto done;
2347 
2348 	err = got_ref_write(ref, repo);
2349 done:
2350 	free(refname);
2351 	if (ref)
2352 		got_ref_close(ref);
2353 	return err;
2354 }
2355 
2356 static const struct got_error *
2357 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
2358 {
2359 	const struct got_error *err = NULL;
2360 
2361 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
2362 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2363 		err = got_error_from_errno("asprintf");
2364 		*fileindex_path = NULL;
2365 	}
2366 	return err;
2367 }
2368 
2369 
2370 static const struct got_error *
2371 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
2372     struct got_worktree *worktree)
2373 {
2374 	const struct got_error *err = NULL;
2375 	FILE *index = NULL;
2376 
2377 	*fileindex_path = NULL;
2378 	*fileindex = got_fileindex_alloc();
2379 	if (*fileindex == NULL)
2380 		return got_error_from_errno("got_fileindex_alloc");
2381 
2382 	err = get_fileindex_path(fileindex_path, worktree);
2383 	if (err)
2384 		goto done;
2385 
2386 	index = fopen(*fileindex_path, "rbe");
2387 	if (index == NULL) {
2388 		if (errno != ENOENT)
2389 			err = got_error_from_errno2("fopen", *fileindex_path);
2390 	} else {
2391 		err = got_fileindex_read(*fileindex, index);
2392 		if (fclose(index) == EOF && err == NULL)
2393 			err = got_error_from_errno("fclose");
2394 	}
2395 done:
2396 	if (err) {
2397 		free(*fileindex_path);
2398 		*fileindex_path = NULL;
2399 		got_fileindex_free(*fileindex);
2400 		*fileindex = NULL;
2401 	}
2402 	return err;
2403 }
2404 
2405 struct bump_base_commit_id_arg {
2406 	struct got_object_id *base_commit_id;
2407 	const char *path;
2408 	size_t path_len;
2409 	const char *entry_name;
2410 	got_worktree_checkout_cb progress_cb;
2411 	void *progress_arg;
2412 };
2413 
2414 /* Bump base commit ID of all files within an updated part of the work tree. */
2415 static const struct got_error *
2416 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
2417 {
2418 	const struct got_error *err;
2419 	struct bump_base_commit_id_arg *a = arg;
2420 
2421 	if (a->entry_name) {
2422 		if (strcmp(ie->path, a->path) != 0)
2423 			return NULL;
2424 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
2425 		return NULL;
2426 
2427 	if (got_fileindex_entry_was_skipped(ie))
2428 		return NULL;
2429 
2430 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
2431 	    SHA1_DIGEST_LENGTH) == 0)
2432 		return NULL;
2433 
2434 	if (a->progress_cb) {
2435 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
2436 		    ie->path);
2437 		if (err)
2438 			return err;
2439 	}
2440 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
2441 	return NULL;
2442 }
2443 
2444 static const struct got_error *
2445 bump_base_commit_id_everywhere(struct got_worktree *worktree,
2446     struct got_fileindex *fileindex,
2447     got_worktree_checkout_cb progress_cb, void *progress_arg)
2448 {
2449 	struct bump_base_commit_id_arg bbc_arg;
2450 
2451 	bbc_arg.base_commit_id = worktree->base_commit_id;
2452 	bbc_arg.entry_name = NULL;
2453 	bbc_arg.path = "";
2454 	bbc_arg.path_len = 0;
2455 	bbc_arg.progress_cb = progress_cb;
2456 	bbc_arg.progress_arg = progress_arg;
2457 
2458 	return got_fileindex_for_each_entry_safe(fileindex,
2459 	    bump_base_commit_id, &bbc_arg);
2460 }
2461 
2462 static const struct got_error *
2463 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
2464 {
2465 	const struct got_error *err = NULL;
2466 	char *new_fileindex_path = NULL;
2467 	FILE *new_index = NULL;
2468 	struct timespec timeout;
2469 
2470 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2471 	    fileindex_path, "");
2472 	if (err)
2473 		goto done;
2474 
2475 	err = got_fileindex_write(fileindex, new_index);
2476 	if (err)
2477 		goto done;
2478 
2479 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2480 		err = got_error_from_errno3("rename", new_fileindex_path,
2481 		    fileindex_path);
2482 		unlink(new_fileindex_path);
2483 	}
2484 
2485 	/*
2486 	 * Sleep for a short amount of time to ensure that files modified after
2487 	 * this program exits have a different time stamp from the one which
2488 	 * was recorded in the file index.
2489 	 */
2490 	timeout.tv_sec = 0;
2491 	timeout.tv_nsec = 1;
2492 	nanosleep(&timeout,  NULL);
2493 done:
2494 	if (new_index)
2495 		fclose(new_index);
2496 	free(new_fileindex_path);
2497 	return err;
2498 }
2499 
2500 static const struct got_error *
2501 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
2502     struct got_object_id **tree_id, const char *wt_relpath,
2503     struct got_commit_object *base_commit, struct got_worktree *worktree,
2504     struct got_repository *repo)
2505 {
2506 	const struct got_error *err = NULL;
2507 	struct got_object_id *id = NULL;
2508 	char *in_repo_path = NULL;
2509 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
2510 
2511 	*entry_type = GOT_OBJ_TYPE_ANY;
2512 	*tree_relpath = NULL;
2513 	*tree_id = NULL;
2514 
2515 	if (wt_relpath[0] == '\0') {
2516 		/* Check out all files within the work tree. */
2517 		*entry_type = GOT_OBJ_TYPE_TREE;
2518 		*tree_relpath = strdup("");
2519 		if (*tree_relpath == NULL) {
2520 			err = got_error_from_errno("strdup");
2521 			goto done;
2522 		}
2523 		err = got_object_id_by_path(tree_id, repo, base_commit,
2524 		    worktree->path_prefix);
2525 		if (err)
2526 			goto done;
2527 		return NULL;
2528 	}
2529 
2530 	/* Check out a subset of files in the work tree. */
2531 
2532 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
2533 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
2534 		err = got_error_from_errno("asprintf");
2535 		goto done;
2536 	}
2537 
2538 	err = got_object_id_by_path(&id, repo, base_commit, in_repo_path);
2539 	if (err)
2540 		goto done;
2541 
2542 	free(in_repo_path);
2543 	in_repo_path = NULL;
2544 
2545 	err = got_object_get_type(entry_type, repo, id);
2546 	if (err)
2547 		goto done;
2548 
2549 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
2550 		/* Check out a single file. */
2551 		if (strchr(wt_relpath, '/')  == NULL) {
2552 			/* Check out a single file in work tree's root dir. */
2553 			in_repo_path = strdup(worktree->path_prefix);
2554 			if (in_repo_path == NULL) {
2555 				err = got_error_from_errno("strdup");
2556 				goto done;
2557 			}
2558 			*tree_relpath = strdup("");
2559 			if (*tree_relpath == NULL) {
2560 				err = got_error_from_errno("strdup");
2561 				goto done;
2562 			}
2563 		} else {
2564 			/* Check out a single file in a subdirectory. */
2565 			err = got_path_dirname(tree_relpath, wt_relpath);
2566 			if (err)
2567 				return err;
2568 			if (asprintf(&in_repo_path, "%s%s%s",
2569 			    worktree->path_prefix, is_root_wt ? "" : "/",
2570 			    *tree_relpath) == -1) {
2571 				err = got_error_from_errno("asprintf");
2572 				goto done;
2573 			}
2574 		}
2575 		err = got_object_id_by_path(tree_id, repo,
2576 		    base_commit, in_repo_path);
2577 	} else {
2578 		/* Check out all files within a subdirectory. */
2579 		*tree_id = got_object_id_dup(id);
2580 		if (*tree_id == NULL) {
2581 			err = got_error_from_errno("got_object_id_dup");
2582 			goto done;
2583 		}
2584 		*tree_relpath = strdup(wt_relpath);
2585 		if (*tree_relpath == NULL) {
2586 			err = got_error_from_errno("strdup");
2587 			goto done;
2588 		}
2589 	}
2590 done:
2591 	free(id);
2592 	free(in_repo_path);
2593 	if (err) {
2594 		*entry_type = GOT_OBJ_TYPE_ANY;
2595 		free(*tree_relpath);
2596 		*tree_relpath = NULL;
2597 		free(*tree_id);
2598 		*tree_id = NULL;
2599 	}
2600 	return err;
2601 }
2602 
2603 static const struct got_error *
2604 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2605     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
2606     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2607     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
2608 {
2609 	const struct got_error *err = NULL;
2610 	struct got_commit_object *commit = NULL;
2611 	struct got_tree_object *tree = NULL;
2612 	struct got_fileindex_diff_tree_cb diff_cb;
2613 	struct diff_cb_arg arg;
2614 
2615 	err = ref_base_commit(worktree, repo);
2616 	if (err) {
2617 		if (!(err->code == GOT_ERR_ERRNO &&
2618 		    (errno == EACCES || errno == EROFS)))
2619 			goto done;
2620 		err = (*progress_cb)(progress_arg,
2621 		    GOT_STATUS_BASE_REF_ERR, worktree->root_path);
2622 		if (err)
2623 			return err;
2624 	}
2625 
2626 	err = got_object_open_as_commit(&commit, repo,
2627 	    worktree->base_commit_id);
2628 	if (err)
2629 		goto done;
2630 
2631 	err = got_object_open_as_tree(&tree, repo, tree_id);
2632 	if (err)
2633 		goto done;
2634 
2635 	if (entry_name &&
2636 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
2637 		err = got_error_path(entry_name, GOT_ERR_NO_TREE_ENTRY);
2638 		goto done;
2639 	}
2640 
2641 	diff_cb.diff_old_new = diff_old_new;
2642 	diff_cb.diff_old = diff_old;
2643 	diff_cb.diff_new = diff_new;
2644 	arg.fileindex = fileindex;
2645 	arg.worktree = worktree;
2646 	arg.repo = repo;
2647 	arg.progress_cb = progress_cb;
2648 	arg.progress_arg = progress_arg;
2649 	arg.cancel_cb = cancel_cb;
2650 	arg.cancel_arg = cancel_arg;
2651 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
2652 	    entry_name, repo, &diff_cb, &arg);
2653 done:
2654 	if (tree)
2655 		got_object_tree_close(tree);
2656 	if (commit)
2657 		got_object_commit_close(commit);
2658 	return err;
2659 }
2660 
2661 const struct got_error *
2662 got_worktree_checkout_files(struct got_worktree *worktree,
2663     struct got_pathlist_head *paths, struct got_repository *repo,
2664     got_worktree_checkout_cb progress_cb, void *progress_arg,
2665     got_cancel_cb cancel_cb, void *cancel_arg)
2666 {
2667 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2668 	struct got_commit_object *commit = NULL;
2669 	struct got_tree_object *tree = NULL;
2670 	struct got_fileindex *fileindex = NULL;
2671 	char *fileindex_path = NULL;
2672 	struct got_pathlist_entry *pe;
2673 	struct tree_path_data {
2674 		STAILQ_ENTRY(tree_path_data) entry;
2675 		struct got_object_id *tree_id;
2676 		int entry_type;
2677 		char *relpath;
2678 		char *entry_name;
2679 	} *tpd = NULL;
2680 	STAILQ_HEAD(tree_paths, tree_path_data) tree_paths;
2681 
2682 	STAILQ_INIT(&tree_paths);
2683 
2684 	err = lock_worktree(worktree, LOCK_EX);
2685 	if (err)
2686 		return err;
2687 
2688 	err = got_object_open_as_commit(&commit, repo,
2689 	    worktree->base_commit_id);
2690 	if (err)
2691 		goto done;
2692 
2693 	/* Map all specified paths to in-repository trees. */
2694 	TAILQ_FOREACH(pe, paths, entry) {
2695 		tpd = malloc(sizeof(*tpd));
2696 		if (tpd == NULL) {
2697 			err = got_error_from_errno("malloc");
2698 			goto done;
2699 		}
2700 
2701 		err = find_tree_entry_for_checkout(&tpd->entry_type,
2702 		    &tpd->relpath, &tpd->tree_id, pe->path, commit,
2703 		    worktree, repo);
2704 		if (err) {
2705 			free(tpd);
2706 			goto done;
2707 		}
2708 
2709 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
2710 			err = got_path_basename(&tpd->entry_name, pe->path);
2711 			if (err) {
2712 				free(tpd->relpath);
2713 				free(tpd->tree_id);
2714 				free(tpd);
2715 				goto done;
2716 			}
2717 		} else
2718 			tpd->entry_name = NULL;
2719 
2720 		STAILQ_INSERT_TAIL(&tree_paths, tpd, entry);
2721 	}
2722 
2723 	/*
2724 	 * Read the file index.
2725 	 * Checking out files is supposed to be an idempotent operation.
2726 	 * If the on-disk file index is incomplete we will try to complete it.
2727 	 */
2728 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2729 	if (err)
2730 		goto done;
2731 
2732 	tpd = STAILQ_FIRST(&tree_paths);
2733 	TAILQ_FOREACH(pe, paths, entry) {
2734 		struct bump_base_commit_id_arg bbc_arg;
2735 
2736 		err = checkout_files(worktree, fileindex, tpd->relpath,
2737 		    tpd->tree_id, tpd->entry_name, repo,
2738 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
2739 		if (err)
2740 			break;
2741 
2742 		bbc_arg.base_commit_id = worktree->base_commit_id;
2743 		bbc_arg.entry_name = tpd->entry_name;
2744 		bbc_arg.path = pe->path;
2745 		bbc_arg.path_len = pe->path_len;
2746 		bbc_arg.progress_cb = progress_cb;
2747 		bbc_arg.progress_arg = progress_arg;
2748 		err = got_fileindex_for_each_entry_safe(fileindex,
2749 		    bump_base_commit_id, &bbc_arg);
2750 		if (err)
2751 			break;
2752 
2753 		tpd = STAILQ_NEXT(tpd, entry);
2754 	}
2755 	sync_err = sync_fileindex(fileindex, fileindex_path);
2756 	if (sync_err && err == NULL)
2757 		err = sync_err;
2758 done:
2759 	free(fileindex_path);
2760 	if (tree)
2761 		got_object_tree_close(tree);
2762 	if (commit)
2763 		got_object_commit_close(commit);
2764 	if (fileindex)
2765 		got_fileindex_free(fileindex);
2766 	while (!STAILQ_EMPTY(&tree_paths)) {
2767 		tpd = STAILQ_FIRST(&tree_paths);
2768 		STAILQ_REMOVE_HEAD(&tree_paths, entry);
2769 		free(tpd->relpath);
2770 		free(tpd->tree_id);
2771 		free(tpd);
2772 	}
2773 	unlockerr = lock_worktree(worktree, LOCK_SH);
2774 	if (unlockerr && err == NULL)
2775 		err = unlockerr;
2776 	return err;
2777 }
2778 
2779 struct merge_file_cb_arg {
2780     struct got_worktree *worktree;
2781     struct got_fileindex *fileindex;
2782     got_worktree_checkout_cb progress_cb;
2783     void *progress_arg;
2784     got_cancel_cb cancel_cb;
2785     void *cancel_arg;
2786     const char *label_orig;
2787     struct got_object_id *commit_id2;
2788     int allow_bad_symlinks;
2789 };
2790 
2791 static const struct got_error *
2792 merge_file_cb(void *arg, struct got_blob_object *blob1,
2793     struct got_blob_object *blob2, FILE *f1, FILE *f2,
2794     struct got_object_id *id1, struct got_object_id *id2,
2795     const char *path1, const char *path2,
2796     mode_t mode1, mode_t mode2, struct got_repository *repo)
2797 {
2798 	static const struct got_error *err = NULL;
2799 	struct merge_file_cb_arg *a = arg;
2800 	struct got_fileindex_entry *ie;
2801 	char *ondisk_path = NULL;
2802 	struct stat sb;
2803 	unsigned char status;
2804 	int local_changes_subsumed;
2805 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
2806 	char *id_str = NULL, *label_deriv2 = NULL;
2807 
2808 	if (blob1 && blob2) {
2809 		ie = got_fileindex_entry_get(a->fileindex, path2,
2810 		    strlen(path2));
2811 		if (ie == NULL)
2812 			return (*a->progress_cb)(a->progress_arg,
2813 			    GOT_STATUS_MISSING, path2);
2814 
2815 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2816 		    path2) == -1)
2817 			return got_error_from_errno("asprintf");
2818 
2819 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2820 		    repo);
2821 		if (err)
2822 			goto done;
2823 
2824 		if (status == GOT_STATUS_DELETE) {
2825 			err = (*a->progress_cb)(a->progress_arg,
2826 			    GOT_STATUS_MERGE, path2);
2827 			goto done;
2828 		}
2829 		if (status != GOT_STATUS_NO_CHANGE &&
2830 		    status != GOT_STATUS_MODIFY &&
2831 		    status != GOT_STATUS_CONFLICT &&
2832 		    status != GOT_STATUS_ADD) {
2833 			err = (*a->progress_cb)(a->progress_arg, status, path2);
2834 			goto done;
2835 		}
2836 
2837 		if (S_ISLNK(mode1) && S_ISLNK(mode2)) {
2838 			char *link_target2;
2839 			err = got_object_blob_read_to_str(&link_target2, blob2);
2840 			if (err)
2841 				goto done;
2842 			err = merge_symlink(a->worktree, blob1, ondisk_path,
2843 			    path2, a->label_orig, link_target2, a->commit_id2,
2844 			    repo, a->progress_cb, a->progress_arg);
2845 			free(link_target2);
2846 		} else {
2847 			int fd;
2848 
2849 			f_orig = got_opentemp();
2850 			if (f_orig == NULL) {
2851 				err = got_error_from_errno("got_opentemp");
2852 				goto done;
2853 			}
2854 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2855 			    f_orig, blob1);
2856 			if (err)
2857 				goto done;
2858 
2859 			f_deriv2 = got_opentemp();
2860 			if (f_deriv2 == NULL)
2861 				goto done;
2862 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2863 			    f_deriv2, blob2);
2864 			if (err)
2865 				goto done;
2866 
2867 			fd = open(ondisk_path,
2868 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
2869 			if (fd == -1) {
2870 				err = got_error_from_errno2("open",
2871 				    ondisk_path);
2872 				goto done;
2873 			}
2874 			f_deriv = fdopen(fd, "r");
2875 			if (f_deriv == NULL) {
2876 				err = got_error_from_errno2("fdopen",
2877 				    ondisk_path);
2878 				close(fd);
2879 				goto done;
2880 			}
2881 			err = got_object_id_str(&id_str, a->commit_id2);
2882 			if (err)
2883 				goto done;
2884 			if (asprintf(&label_deriv2, "%s: commit %s",
2885 			    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
2886 				err = got_error_from_errno("asprintf");
2887 				goto done;
2888 			}
2889 			err = merge_file(&local_changes_subsumed, a->worktree,
2890 			    f_orig, f_deriv, f_deriv2, ondisk_path, path2,
2891 			    sb.st_mode, a->label_orig, NULL, label_deriv2,
2892 			    GOT_DIFF_ALGORITHM_PATIENCE, repo,
2893 			    a->progress_cb, a->progress_arg);
2894 		}
2895 	} else if (blob1) {
2896 		ie = got_fileindex_entry_get(a->fileindex, path1,
2897 		    strlen(path1));
2898 		if (ie == NULL)
2899 			return (*a->progress_cb)(a->progress_arg,
2900 			    GOT_STATUS_MISSING, path1);
2901 
2902 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2903 		    path1) == -1)
2904 			return got_error_from_errno("asprintf");
2905 
2906 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2907 		    repo);
2908 		if (err)
2909 			goto done;
2910 
2911 		switch (status) {
2912 		case GOT_STATUS_NO_CHANGE:
2913 			err = (*a->progress_cb)(a->progress_arg,
2914 			    GOT_STATUS_DELETE, path1);
2915 			if (err)
2916 				goto done;
2917 			err = remove_ondisk_file(a->worktree->root_path, path1);
2918 			if (err)
2919 				goto done;
2920 			if (ie)
2921 				got_fileindex_entry_mark_deleted_from_disk(ie);
2922 			break;
2923 		case GOT_STATUS_DELETE:
2924 		case GOT_STATUS_MISSING:
2925 			err = (*a->progress_cb)(a->progress_arg,
2926 			    GOT_STATUS_DELETE, path1);
2927 			if (err)
2928 				goto done;
2929 			if (ie)
2930 				got_fileindex_entry_mark_deleted_from_disk(ie);
2931 			break;
2932 		case GOT_STATUS_ADD: {
2933 			struct got_object_id *id;
2934 			FILE *blob1_f;
2935 			off_t blob1_size;
2936 			/*
2937 			 * Delete the added file only if its content already
2938 			 * exists in the repository.
2939 			 */
2940 			err = got_object_blob_file_create(&id, &blob1_f,
2941 			    &blob1_size, path1);
2942 			if (err)
2943 				goto done;
2944 			if (got_object_id_cmp(id, id1) == 0) {
2945 				err = (*a->progress_cb)(a->progress_arg,
2946 				    GOT_STATUS_DELETE, path1);
2947 				if (err)
2948 					goto done;
2949 				err = remove_ondisk_file(a->worktree->root_path,
2950 				    path1);
2951 				if (err)
2952 					goto done;
2953 				if (ie)
2954 					got_fileindex_entry_remove(a->fileindex,
2955 					    ie);
2956 			} else {
2957 				err = (*a->progress_cb)(a->progress_arg,
2958 				    GOT_STATUS_CANNOT_DELETE, path1);
2959 			}
2960 			if (fclose(blob1_f) == EOF && err == NULL)
2961 				err = got_error_from_errno("fclose");
2962 			free(id);
2963 			if (err)
2964 				goto done;
2965 			break;
2966 		}
2967 		case GOT_STATUS_MODIFY:
2968 		case GOT_STATUS_CONFLICT:
2969 			err = (*a->progress_cb)(a->progress_arg,
2970 			    GOT_STATUS_CANNOT_DELETE, path1);
2971 			if (err)
2972 				goto done;
2973 			break;
2974 		case GOT_STATUS_OBSTRUCTED:
2975 			err = (*a->progress_cb)(a->progress_arg, status, path1);
2976 			if (err)
2977 				goto done;
2978 			break;
2979 		default:
2980 			break;
2981 		}
2982 	} else if (blob2) {
2983 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2984 		    path2) == -1)
2985 			return got_error_from_errno("asprintf");
2986 		ie = got_fileindex_entry_get(a->fileindex, path2,
2987 		    strlen(path2));
2988 		if (ie) {
2989 			err = get_file_status(&status, &sb, ie, ondisk_path,
2990 			    -1, NULL, repo);
2991 			if (err)
2992 				goto done;
2993 			if (status != GOT_STATUS_NO_CHANGE &&
2994 			    status != GOT_STATUS_MODIFY &&
2995 			    status != GOT_STATUS_CONFLICT &&
2996 			    status != GOT_STATUS_ADD) {
2997 				err = (*a->progress_cb)(a->progress_arg,
2998 				    status, path2);
2999 				goto done;
3000 			}
3001 			if (S_ISLNK(mode2) && S_ISLNK(sb.st_mode)) {
3002 				char *link_target2;
3003 				err = got_object_blob_read_to_str(&link_target2,
3004 				    blob2);
3005 				if (err)
3006 					goto done;
3007 				err = merge_symlink(a->worktree, NULL,
3008 				    ondisk_path, path2, a->label_orig,
3009 				    link_target2, a->commit_id2, repo,
3010 				    a->progress_cb, a->progress_arg);
3011 				free(link_target2);
3012 			} else if (S_ISREG(sb.st_mode)) {
3013 				err = merge_blob(&local_changes_subsumed,
3014 				    a->worktree, NULL, ondisk_path, path2,
3015 				    sb.st_mode, a->label_orig, blob2,
3016 				    a->commit_id2, repo, a->progress_cb,
3017 				    a->progress_arg);
3018 			} else {
3019 				err = got_error_path(ondisk_path,
3020 				    GOT_ERR_FILE_OBSTRUCTED);
3021 			}
3022 			if (err)
3023 				goto done;
3024 			if (status == GOT_STATUS_DELETE) {
3025 				err = got_fileindex_entry_update(ie,
3026 				    a->worktree->root_fd, path2, blob2->id.sha1,
3027 				    a->worktree->base_commit_id->sha1, 0);
3028 				if (err)
3029 					goto done;
3030 			}
3031 		} else {
3032 			int is_bad_symlink = 0;
3033 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
3034 			if (S_ISLNK(mode2)) {
3035 				err = install_symlink(&is_bad_symlink,
3036 				    a->worktree, ondisk_path, path2, blob2, 0,
3037 				    0, 1, a->allow_bad_symlinks, repo,
3038 				    a->progress_cb, a->progress_arg);
3039 			} else {
3040 				err = install_blob(a->worktree, ondisk_path, path2,
3041 				    mode2, sb.st_mode, blob2, 0, 0, 0, 1, repo,
3042 				    a->progress_cb, a->progress_arg);
3043 			}
3044 			if (err)
3045 				goto done;
3046 			err = got_fileindex_entry_alloc(&ie, path2);
3047 			if (err)
3048 				goto done;
3049 			err = got_fileindex_entry_update(ie,
3050 			    a->worktree->root_fd, path2, NULL, NULL, 1);
3051 			if (err) {
3052 				got_fileindex_entry_free(ie);
3053 				goto done;
3054 			}
3055 			err = got_fileindex_entry_add(a->fileindex, ie);
3056 			if (err) {
3057 				got_fileindex_entry_free(ie);
3058 				goto done;
3059 			}
3060 			if (is_bad_symlink) {
3061 				got_fileindex_entry_filetype_set(ie,
3062 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
3063 			}
3064 		}
3065 	}
3066 done:
3067 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
3068 		err = got_error_from_errno("fclose");
3069 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
3070 		err = got_error_from_errno("fclose");
3071 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
3072 		err = got_error_from_errno("fclose");
3073 	free(id_str);
3074 	free(label_deriv2);
3075 	free(ondisk_path);
3076 	return err;
3077 }
3078 
3079 static const struct got_error *
3080 check_mixed_commits(void *arg, struct got_fileindex_entry *ie)
3081 {
3082 	struct got_worktree *worktree = arg;
3083 
3084 	/* Reject merges into a work tree with mixed base commits. */
3085 	if (got_fileindex_entry_has_commit(ie) &&
3086 	    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
3087 	    SHA1_DIGEST_LENGTH) != 0)
3088 		return got_error(GOT_ERR_MIXED_COMMITS);
3089 
3090 	return NULL;
3091 }
3092 
3093 struct check_merge_conflicts_arg {
3094 	struct got_worktree *worktree;
3095 	struct got_fileindex *fileindex;
3096 	struct got_repository *repo;
3097 };
3098 
3099 static const struct got_error *
3100 check_merge_conflicts(void *arg, struct got_blob_object *blob1,
3101     struct got_blob_object *blob2, FILE *f1, FILE *f2,
3102     struct got_object_id *id1, struct got_object_id *id2,
3103     const char *path1, const char *path2,
3104     mode_t mode1, mode_t mode2, struct got_repository *repo)
3105 {
3106 	const struct got_error *err = NULL;
3107 	struct check_merge_conflicts_arg *a = arg;
3108 	unsigned char status;
3109 	struct stat sb;
3110 	struct got_fileindex_entry *ie;
3111 	const char *path = path2 ? path2 : path1;
3112 	struct got_object_id *id = id2 ? id2 : id1;
3113 	char *ondisk_path;
3114 
3115 	if (id == NULL)
3116 		return NULL;
3117 
3118 	ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
3119 	if (ie == NULL)
3120 		return NULL;
3121 
3122 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3123 	    == -1)
3124 		return got_error_from_errno("asprintf");
3125 
3126 	/* Reject merges into a work tree with conflicted files. */
3127 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
3128 	free(ondisk_path);
3129 	if (err)
3130 		return err;
3131 	if (status == GOT_STATUS_CONFLICT)
3132 		return got_error(GOT_ERR_CONFLICTS);
3133 
3134 	return NULL;
3135 }
3136 
3137 static const struct got_error *
3138 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
3139     const char *fileindex_path, struct got_object_id *commit_id1,
3140     struct got_object_id *commit_id2, struct got_repository *repo,
3141     got_worktree_checkout_cb progress_cb, void *progress_arg,
3142     got_cancel_cb cancel_cb, void *cancel_arg)
3143 {
3144 	const struct got_error *err = NULL, *sync_err;
3145 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
3146 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
3147 	struct got_commit_object *commit1 = NULL, *commit2 = NULL;
3148 	struct check_merge_conflicts_arg cmc_arg;
3149 	struct merge_file_cb_arg arg;
3150 	char *label_orig = NULL;
3151 	FILE *f1 = NULL, *f2 = NULL;
3152 	int fd1 = -1, fd2 = -1;
3153 
3154 	if (commit_id1) {
3155 		err = got_object_open_as_commit(&commit1, repo, commit_id1);
3156 		if (err)
3157 			goto done;
3158 		err = got_object_id_by_path(&tree_id1, repo, commit1,
3159 		    worktree->path_prefix);
3160 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3161 			goto done;
3162 	}
3163 	if (tree_id1) {
3164 		char *id_str;
3165 
3166 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
3167 		if (err)
3168 			goto done;
3169 
3170 		err = got_object_id_str(&id_str, commit_id1);
3171 		if (err)
3172 			goto done;
3173 
3174 		if (asprintf(&label_orig, "%s: commit %s",
3175 		    GOT_MERGE_LABEL_BASE, id_str) == -1) {
3176 			err = got_error_from_errno("asprintf");
3177 			free(id_str);
3178 			goto done;
3179 		}
3180 		free(id_str);
3181 
3182 		f1 = got_opentemp();
3183 		if (f1 == NULL) {
3184 			err = got_error_from_errno("got_opentemp");
3185 			goto done;
3186 		}
3187 	}
3188 
3189 	err = got_object_open_as_commit(&commit2, repo, commit_id2);
3190 	if (err)
3191 		goto done;
3192 
3193 	err = got_object_id_by_path(&tree_id2, repo, commit2,
3194 	    worktree->path_prefix);
3195 	if (err)
3196 		goto done;
3197 
3198 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
3199 	if (err)
3200 		goto done;
3201 
3202 	f2 = got_opentemp();
3203 	if (f2 == NULL) {
3204 		err = got_error_from_errno("got_opentemp");
3205 		goto done;
3206 	}
3207 
3208 	fd1 = got_opentempfd();
3209 	if (fd1 == -1) {
3210 		err = got_error_from_errno("got_opentempfd");
3211 		goto done;
3212 	}
3213 
3214 	fd2 = got_opentempfd();
3215 	if (fd2 == -1) {
3216 		err = got_error_from_errno("got_opentempfd");
3217 		goto done;
3218 	}
3219 
3220 	cmc_arg.worktree = worktree;
3221 	cmc_arg.fileindex = fileindex;
3222 	cmc_arg.repo = repo;
3223 	err = got_diff_tree(tree1, tree2, f1, f2, fd1, fd2, "", "", repo,
3224 	    check_merge_conflicts, &cmc_arg, 0);
3225 	if (err)
3226 		goto done;
3227 
3228 	arg.worktree = worktree;
3229 	arg.fileindex = fileindex;
3230 	arg.progress_cb = progress_cb;
3231 	arg.progress_arg = progress_arg;
3232 	arg.cancel_cb = cancel_cb;
3233 	arg.cancel_arg = cancel_arg;
3234 	arg.label_orig = label_orig;
3235 	arg.commit_id2 = commit_id2;
3236 	arg.allow_bad_symlinks = 1; /* preserve bad symlinks across merges */
3237 	err = got_diff_tree(tree1, tree2, f1, f2, fd1, fd2, "", "", repo,
3238 	    merge_file_cb, &arg, 1);
3239 	sync_err = sync_fileindex(fileindex, fileindex_path);
3240 	if (sync_err && err == NULL)
3241 		err = sync_err;
3242 done:
3243 	if (commit1)
3244 		got_object_commit_close(commit1);
3245 	if (commit2)
3246 		got_object_commit_close(commit2);
3247 	if (tree1)
3248 		got_object_tree_close(tree1);
3249 	if (tree2)
3250 		got_object_tree_close(tree2);
3251 	if (f1 && fclose(f1) == EOF && err == NULL)
3252 		err = got_error_from_errno("fclose");
3253 	if (f2 && fclose(f2) == EOF && err == NULL)
3254 		err = got_error_from_errno("fclose");
3255 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
3256 		err = got_error_from_errno("close");
3257 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
3258 		err = got_error_from_errno("close");
3259 	free(label_orig);
3260 	return err;
3261 }
3262 
3263 const struct got_error *
3264 got_worktree_merge_files(struct got_worktree *worktree,
3265     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
3266     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
3267     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
3268 {
3269 	const struct got_error *err, *unlockerr;
3270 	char *fileindex_path = NULL;
3271 	struct got_fileindex *fileindex = NULL;
3272 
3273 	err = lock_worktree(worktree, LOCK_EX);
3274 	if (err)
3275 		return err;
3276 
3277 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3278 	if (err)
3279 		goto done;
3280 
3281 	err = got_fileindex_for_each_entry_safe(fileindex, check_mixed_commits,
3282 	    worktree);
3283 	if (err)
3284 		goto done;
3285 
3286 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
3287 	    commit_id2, repo, progress_cb, progress_arg,
3288 	    cancel_cb, cancel_arg);
3289 done:
3290 	if (fileindex)
3291 		got_fileindex_free(fileindex);
3292 	free(fileindex_path);
3293 	unlockerr = lock_worktree(worktree, LOCK_SH);
3294 	if (unlockerr && err == NULL)
3295 		err = unlockerr;
3296 	return err;
3297 }
3298 
3299 struct diff_dir_cb_arg {
3300     struct got_fileindex *fileindex;
3301     struct got_worktree *worktree;
3302     const char *status_path;
3303     size_t status_path_len;
3304     struct got_repository *repo;
3305     got_worktree_status_cb status_cb;
3306     void *status_arg;
3307     got_cancel_cb cancel_cb;
3308     void *cancel_arg;
3309     /* A pathlist containing per-directory pathlists of ignore patterns. */
3310     struct got_pathlist_head *ignores;
3311     int report_unchanged;
3312     int no_ignores;
3313 };
3314 
3315 static const struct got_error *
3316 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
3317     int dirfd, const char *de_name,
3318     got_worktree_status_cb status_cb, void *status_arg,
3319     struct got_repository *repo, int report_unchanged)
3320 {
3321 	const struct got_error *err = NULL;
3322 	unsigned char status = GOT_STATUS_NO_CHANGE;
3323 	unsigned char staged_status = get_staged_status(ie);
3324 	struct stat sb;
3325 	struct got_object_id blob_id, commit_id, staged_blob_id;
3326 	struct got_object_id *blob_idp = NULL, *commit_idp = NULL;
3327 	struct got_object_id *staged_blob_idp = NULL;
3328 
3329 	err = get_file_status(&status, &sb, ie, abspath, dirfd, de_name, repo);
3330 	if (err)
3331 		return err;
3332 
3333 	if (status == GOT_STATUS_NO_CHANGE &&
3334 	    staged_status == GOT_STATUS_NO_CHANGE && !report_unchanged)
3335 		return NULL;
3336 
3337 	if (got_fileindex_entry_has_blob(ie)) {
3338 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
3339 		blob_idp = &blob_id;
3340 	}
3341 	if (got_fileindex_entry_has_commit(ie)) {
3342 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
3343 		commit_idp = &commit_id;
3344 	}
3345 	if (staged_status == GOT_STATUS_ADD ||
3346 	    staged_status == GOT_STATUS_MODIFY) {
3347 		memcpy(staged_blob_id.sha1, ie->staged_blob_sha1,
3348 		    SHA1_DIGEST_LENGTH);
3349 		staged_blob_idp = &staged_blob_id;
3350 	}
3351 
3352 	return (*status_cb)(status_arg, status, staged_status,
3353 	    ie->path, blob_idp, staged_blob_idp, commit_idp, dirfd, de_name);
3354 }
3355 
3356 static const struct got_error *
3357 status_old_new(void *arg, struct got_fileindex_entry *ie,
3358     struct dirent *de, const char *parent_path, int dirfd)
3359 {
3360 	const struct got_error *err = NULL;
3361 	struct diff_dir_cb_arg *a = arg;
3362 	char *abspath;
3363 
3364 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3365 		return got_error(GOT_ERR_CANCELLED);
3366 
3367 	if (got_path_cmp(parent_path, a->status_path,
3368 	    strlen(parent_path), a->status_path_len) != 0 &&
3369 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
3370 		return NULL;
3371 
3372 	if (parent_path[0]) {
3373 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
3374 		    parent_path, de->d_name) == -1)
3375 			return got_error_from_errno("asprintf");
3376 	} else {
3377 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
3378 		    de->d_name) == -1)
3379 			return got_error_from_errno("asprintf");
3380 	}
3381 
3382 	err = report_file_status(ie, abspath, dirfd, de->d_name,
3383 	    a->status_cb, a->status_arg, a->repo, a->report_unchanged);
3384 	free(abspath);
3385 	return err;
3386 }
3387 
3388 static const struct got_error *
3389 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
3390 {
3391 	struct diff_dir_cb_arg *a = arg;
3392 	struct got_object_id blob_id, commit_id;
3393 	unsigned char status;
3394 
3395 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3396 		return got_error(GOT_ERR_CANCELLED);
3397 
3398 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
3399 		return NULL;
3400 
3401 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
3402 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
3403 	if (got_fileindex_entry_has_file_on_disk(ie))
3404 		status = GOT_STATUS_MISSING;
3405 	else
3406 		status = GOT_STATUS_DELETE;
3407 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
3408 	    ie->path, &blob_id, NULL, &commit_id, -1, NULL);
3409 }
3410 
3411 static void
3412 free_ignorelist(struct got_pathlist_head *ignorelist)
3413 {
3414 	struct got_pathlist_entry *pe;
3415 
3416 	TAILQ_FOREACH(pe, ignorelist, entry)
3417 		free((char *)pe->path);
3418 	got_pathlist_free(ignorelist);
3419 }
3420 
3421 static void
3422 free_ignores(struct got_pathlist_head *ignores)
3423 {
3424 	struct got_pathlist_entry *pe;
3425 
3426 	TAILQ_FOREACH(pe, ignores, entry) {
3427 		struct got_pathlist_head *ignorelist = pe->data;
3428 		free_ignorelist(ignorelist);
3429 		free((char *)pe->path);
3430 	}
3431 	got_pathlist_free(ignores);
3432 }
3433 
3434 static const struct got_error *
3435 read_ignores(struct got_pathlist_head *ignores, const char *path, FILE *f)
3436 {
3437 	const struct got_error *err = NULL;
3438 	struct got_pathlist_entry *pe = NULL;
3439 	struct got_pathlist_head *ignorelist;
3440 	char *line = NULL, *pattern, *dirpath = NULL;
3441 	size_t linesize = 0;
3442 	ssize_t linelen;
3443 
3444 	ignorelist = calloc(1, sizeof(*ignorelist));
3445 	if (ignorelist == NULL)
3446 		return got_error_from_errno("calloc");
3447 	TAILQ_INIT(ignorelist);
3448 
3449 	while ((linelen = getline(&line, &linesize, f)) != -1) {
3450 		if (linelen > 0 && line[linelen - 1] == '\n')
3451 			line[linelen - 1] = '\0';
3452 
3453 		/* Git's ignores may contain comments. */
3454 		if (line[0] == '#')
3455 			continue;
3456 
3457 		/* Git's negated patterns are not (yet?) supported. */
3458 		if (line[0] == '!')
3459 			continue;
3460 
3461 		if (asprintf(&pattern, "%s%s%s", path, path[0] ? "/" : "",
3462 		    line) == -1) {
3463 			err = got_error_from_errno("asprintf");
3464 			goto done;
3465 		}
3466 		err = got_pathlist_insert(NULL, ignorelist, pattern, NULL);
3467 		if (err)
3468 			goto done;
3469 	}
3470 	if (ferror(f)) {
3471 		err = got_error_from_errno("getline");
3472 		goto done;
3473 	}
3474 
3475 	dirpath = strdup(path);
3476 	if (dirpath == NULL) {
3477 		err = got_error_from_errno("strdup");
3478 		goto done;
3479 	}
3480 	err = got_pathlist_insert(&pe, ignores, dirpath, ignorelist);
3481 done:
3482 	free(line);
3483 	if (err || pe == NULL) {
3484 		free(dirpath);
3485 		free_ignorelist(ignorelist);
3486 	}
3487 	return err;
3488 }
3489 
3490 static int
3491 match_ignores(struct got_pathlist_head *ignores, const char *path)
3492 {
3493 	struct got_pathlist_entry *pe;
3494 
3495 	/* Handle patterns which match in all directories. */
3496 	TAILQ_FOREACH(pe, ignores, entry) {
3497 		struct got_pathlist_head *ignorelist = pe->data;
3498 		struct got_pathlist_entry *pi;
3499 
3500 		TAILQ_FOREACH(pi, ignorelist, entry) {
3501 			const char *p, *pattern = pi->path;
3502 
3503 			if (strncmp(pattern, "**/", 3) != 0)
3504 				continue;
3505 			pattern += 3;
3506 			p = path;
3507 			while (*p) {
3508 				if (fnmatch(pattern, p,
3509 				    FNM_PATHNAME | FNM_LEADING_DIR)) {
3510 					/* Retry in next directory. */
3511 					while (*p && *p != '/')
3512 						p++;
3513 					while (*p == '/')
3514 						p++;
3515 					continue;
3516 				}
3517 				return 1;
3518 			}
3519 		}
3520 	}
3521 
3522 	/*
3523 	 * The ignores pathlist contains ignore lists from children before
3524 	 * parents, so we can find the most specific ignorelist by walking
3525 	 * ignores backwards.
3526 	 */
3527 	pe = TAILQ_LAST(ignores, got_pathlist_head);
3528 	while (pe) {
3529 		if (got_path_is_child(path, pe->path, pe->path_len)) {
3530 			struct got_pathlist_head *ignorelist = pe->data;
3531 			struct got_pathlist_entry *pi;
3532 			TAILQ_FOREACH(pi, ignorelist, entry) {
3533 				const char *pattern = pi->path;
3534 				int flags = FNM_LEADING_DIR;
3535 				if (strstr(pattern, "/**/") == NULL)
3536 					flags |= FNM_PATHNAME;
3537 				if (fnmatch(pattern, path, flags))
3538 					continue;
3539 				return 1;
3540 			}
3541 		}
3542 		pe = TAILQ_PREV(pe, got_pathlist_head, entry);
3543 	}
3544 
3545 	return 0;
3546 }
3547 
3548 static const struct got_error *
3549 add_ignores(struct got_pathlist_head *ignores, const char *root_path,
3550     const char *path, int dirfd, const char *ignores_filename)
3551 {
3552 	const struct got_error *err = NULL;
3553 	char *ignorespath;
3554 	int fd = -1;
3555 	FILE *ignoresfile = NULL;
3556 
3557 	if (asprintf(&ignorespath, "%s/%s%s%s", root_path, path,
3558 	    path[0] ? "/" : "", ignores_filename) == -1)
3559 		return got_error_from_errno("asprintf");
3560 
3561 	if (dirfd != -1) {
3562 		fd = openat(dirfd, ignores_filename,
3563 		    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
3564 		if (fd == -1) {
3565 			if (errno != ENOENT && errno != EACCES)
3566 				err = got_error_from_errno2("openat",
3567 				    ignorespath);
3568 		} else {
3569 			ignoresfile = fdopen(fd, "r");
3570 			if (ignoresfile == NULL)
3571 				err = got_error_from_errno2("fdopen",
3572 				    ignorespath);
3573 			else {
3574 				fd = -1;
3575 				err = read_ignores(ignores, path, ignoresfile);
3576 			}
3577 		}
3578 	} else {
3579 		ignoresfile = fopen(ignorespath, "re");
3580 		if (ignoresfile == NULL) {
3581 			if (errno != ENOENT && errno != EACCES)
3582 				err = got_error_from_errno2("fopen",
3583 				    ignorespath);
3584 		} else
3585 			err = read_ignores(ignores, path, ignoresfile);
3586 	}
3587 
3588 	if (ignoresfile && fclose(ignoresfile) == EOF && err == NULL)
3589 		err = got_error_from_errno2("fclose", path);
3590 	if (fd != -1 && close(fd) == -1 && err == NULL)
3591 		err = got_error_from_errno2("close", path);
3592 	free(ignorespath);
3593 	return err;
3594 }
3595 
3596 static const struct got_error *
3597 status_new(int *ignore, void *arg, struct dirent *de, const char *parent_path,
3598     int dirfd)
3599 {
3600 	const struct got_error *err = NULL;
3601 	struct diff_dir_cb_arg *a = arg;
3602 	char *path = NULL;
3603 
3604 	if (ignore != NULL)
3605 		*ignore = 0;
3606 
3607 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3608 		return got_error(GOT_ERR_CANCELLED);
3609 
3610 	if (parent_path[0]) {
3611 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
3612 			return got_error_from_errno("asprintf");
3613 	} else {
3614 		path = de->d_name;
3615 	}
3616 
3617 	if (de->d_type == DT_DIR) {
3618 		if (!a->no_ignores && ignore != NULL &&
3619 		    match_ignores(a->ignores, path))
3620 			*ignore = 1;
3621 	} else if (!match_ignores(a->ignores, path) &&
3622 	    got_path_is_child(path, a->status_path, a->status_path_len))
3623 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
3624 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3625 	if (parent_path[0])
3626 		free(path);
3627 	return err;
3628 }
3629 
3630 static const struct got_error *
3631 status_traverse(void *arg, const char *path, int dirfd)
3632 {
3633 	const struct got_error *err = NULL;
3634 	struct diff_dir_cb_arg *a = arg;
3635 
3636 	if (a->no_ignores)
3637 		return NULL;
3638 
3639 	err = add_ignores(a->ignores, a->worktree->root_path,
3640 	    path, dirfd, ".cvsignore");
3641 	if (err)
3642 		return err;
3643 
3644 	err = add_ignores(a->ignores, a->worktree->root_path, path,
3645 	    dirfd, ".gitignore");
3646 
3647 	return err;
3648 }
3649 
3650 static const struct got_error *
3651 report_single_file_status(const char *path, const char *ondisk_path,
3652     struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
3653     void *status_arg, struct got_repository *repo, int report_unchanged,
3654     struct got_pathlist_head *ignores, int no_ignores)
3655 {
3656 	struct got_fileindex_entry *ie;
3657 	struct stat sb;
3658 
3659 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3660 	if (ie)
3661 		return report_file_status(ie, ondisk_path, -1, NULL,
3662 		    status_cb, status_arg, repo, report_unchanged);
3663 
3664 	if (lstat(ondisk_path, &sb) == -1) {
3665 		if (errno != ENOENT)
3666 			return got_error_from_errno2("lstat", ondisk_path);
3667 		return (*status_cb)(status_arg, GOT_STATUS_NONEXISTENT,
3668 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3669 	}
3670 
3671 	if (!no_ignores && match_ignores(ignores, path))
3672 		return NULL;
3673 
3674 	if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
3675 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
3676 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3677 
3678 	return NULL;
3679 }
3680 
3681 static const struct got_error *
3682 add_ignores_from_parent_paths(struct got_pathlist_head *ignores,
3683     const char *root_path, const char *path)
3684 {
3685 	const struct got_error *err;
3686 	char *parent_path, *next_parent_path = NULL;
3687 
3688 	err = add_ignores(ignores, root_path, "", -1,
3689 	    ".cvsignore");
3690 	if (err)
3691 		return err;
3692 
3693 	err = add_ignores(ignores, root_path, "", -1,
3694 	    ".gitignore");
3695 	if (err)
3696 		return err;
3697 
3698 	err = got_path_dirname(&parent_path, path);
3699 	if (err) {
3700 		if (err->code == GOT_ERR_BAD_PATH)
3701 			return NULL; /* cannot traverse parent */
3702 		return err;
3703 	}
3704 	for (;;) {
3705 		err = add_ignores(ignores, root_path, parent_path, -1,
3706 		    ".cvsignore");
3707 		if (err)
3708 			break;
3709 		err = add_ignores(ignores, root_path, parent_path, -1,
3710 		    ".gitignore");
3711 		if (err)
3712 			break;
3713 		err = got_path_dirname(&next_parent_path, parent_path);
3714 		if (err) {
3715 			if (err->code == GOT_ERR_BAD_PATH)
3716 				err = NULL; /* traversed everything */
3717 			break;
3718 		}
3719 		if (got_path_is_root_dir(parent_path))
3720 			break;
3721 		free(parent_path);
3722 		parent_path = next_parent_path;
3723 		next_parent_path = NULL;
3724 	}
3725 
3726 	free(parent_path);
3727 	free(next_parent_path);
3728 	return err;
3729 }
3730 
3731 static const struct got_error *
3732 worktree_status(struct got_worktree *worktree, const char *path,
3733     struct got_fileindex *fileindex, struct got_repository *repo,
3734     got_worktree_status_cb status_cb, void *status_arg,
3735     got_cancel_cb cancel_cb, void *cancel_arg, int no_ignores,
3736     int report_unchanged)
3737 {
3738 	const struct got_error *err = NULL;
3739 	int fd = -1;
3740 	struct got_fileindex_diff_dir_cb fdiff_cb;
3741 	struct diff_dir_cb_arg arg;
3742 	char *ondisk_path = NULL;
3743 	struct got_pathlist_head ignores;
3744 	struct got_fileindex_entry *ie;
3745 
3746 	TAILQ_INIT(&ignores);
3747 
3748 	if (asprintf(&ondisk_path, "%s%s%s",
3749 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
3750 		return got_error_from_errno("asprintf");
3751 
3752 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3753 	if (ie) {
3754 		err = report_single_file_status(path, ondisk_path,
3755 		    fileindex, status_cb, status_arg, repo,
3756 		    report_unchanged, &ignores, no_ignores);
3757 		goto done;
3758 	}
3759 
3760 	fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC);
3761 	if (fd == -1) {
3762 		if (errno != ENOTDIR && errno != ENOENT && errno != EACCES &&
3763 		    !got_err_open_nofollow_on_symlink())
3764 			err = got_error_from_errno2("open", ondisk_path);
3765 		else {
3766 			if (!no_ignores) {
3767 				err = add_ignores_from_parent_paths(&ignores,
3768 				    worktree->root_path, ondisk_path);
3769 				if (err)
3770 					goto done;
3771 			}
3772 			err = report_single_file_status(path, ondisk_path,
3773 			    fileindex, status_cb, status_arg, repo,
3774 			    report_unchanged, &ignores, no_ignores);
3775 		}
3776 	} else {
3777 		fdiff_cb.diff_old_new = status_old_new;
3778 		fdiff_cb.diff_old = status_old;
3779 		fdiff_cb.diff_new = status_new;
3780 		fdiff_cb.diff_traverse = status_traverse;
3781 		arg.fileindex = fileindex;
3782 		arg.worktree = worktree;
3783 		arg.status_path = path;
3784 		arg.status_path_len = strlen(path);
3785 		arg.repo = repo;
3786 		arg.status_cb = status_cb;
3787 		arg.status_arg = status_arg;
3788 		arg.cancel_cb = cancel_cb;
3789 		arg.cancel_arg = cancel_arg;
3790 		arg.report_unchanged = report_unchanged;
3791 		arg.no_ignores = no_ignores;
3792 		if (!no_ignores) {
3793 			err = add_ignores_from_parent_paths(&ignores,
3794 			    worktree->root_path, path);
3795 			if (err)
3796 				goto done;
3797 		}
3798 		arg.ignores = &ignores;
3799 		err = got_fileindex_diff_dir(fileindex, fd,
3800 		    worktree->root_path, path, repo, &fdiff_cb, &arg);
3801 	}
3802 done:
3803 	free_ignores(&ignores);
3804 	if (fd != -1 && close(fd) == -1 && err == NULL)
3805 		err = got_error_from_errno("close");
3806 	free(ondisk_path);
3807 	return err;
3808 }
3809 
3810 const struct got_error *
3811 got_worktree_status(struct got_worktree *worktree,
3812     struct got_pathlist_head *paths, struct got_repository *repo,
3813     int no_ignores, got_worktree_status_cb status_cb, void *status_arg,
3814     got_cancel_cb cancel_cb, void *cancel_arg)
3815 {
3816 	const struct got_error *err = NULL;
3817 	char *fileindex_path = NULL;
3818 	struct got_fileindex *fileindex = NULL;
3819 	struct got_pathlist_entry *pe;
3820 
3821 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3822 	if (err)
3823 		return err;
3824 
3825 	TAILQ_FOREACH(pe, paths, entry) {
3826 		err = worktree_status(worktree, pe->path, fileindex, repo,
3827 			status_cb, status_arg, cancel_cb, cancel_arg,
3828 			no_ignores, 0);
3829 		if (err)
3830 			break;
3831 	}
3832 	free(fileindex_path);
3833 	got_fileindex_free(fileindex);
3834 	return err;
3835 }
3836 
3837 const struct got_error *
3838 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
3839     const char *arg)
3840 {
3841 	const struct got_error *err = NULL;
3842 	char *resolved = NULL, *cwd = NULL, *path = NULL;
3843 	size_t len;
3844 	struct stat sb;
3845 	char *abspath = NULL;
3846 	char canonpath[PATH_MAX];
3847 
3848 	*wt_path = NULL;
3849 
3850 	cwd = getcwd(NULL, 0);
3851 	if (cwd == NULL)
3852 		return got_error_from_errno("getcwd");
3853 
3854 	if (lstat(arg, &sb) == -1) {
3855 		if (errno != ENOENT) {
3856 			err = got_error_from_errno2("lstat", arg);
3857 			goto done;
3858 		}
3859 		sb.st_mode = 0;
3860 	}
3861 	if (S_ISLNK(sb.st_mode)) {
3862 		/*
3863 		 * We cannot use realpath(3) with symlinks since we want to
3864 		 * operate on the symlink itself.
3865 		 * But we can make the path absolute, assuming it is relative
3866 		 * to the current working directory, and then canonicalize it.
3867 		 */
3868 		if (!got_path_is_absolute(arg)) {
3869 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3870 				err = got_error_from_errno("asprintf");
3871 				goto done;
3872 			}
3873 
3874 		}
3875 		err = got_canonpath(abspath ? abspath : arg, canonpath,
3876 		    sizeof(canonpath));
3877 		if (err)
3878 			goto done;
3879 		resolved = strdup(canonpath);
3880 		if (resolved == NULL) {
3881 			err = got_error_from_errno("strdup");
3882 			goto done;
3883 		}
3884 	} else {
3885 		resolved = realpath(arg, NULL);
3886 		if (resolved == NULL) {
3887 			if (errno != ENOENT) {
3888 				err = got_error_from_errno2("realpath", arg);
3889 				goto done;
3890 			}
3891 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3892 				err = got_error_from_errno("asprintf");
3893 				goto done;
3894 			}
3895 			err = got_canonpath(abspath, canonpath,
3896 			    sizeof(canonpath));
3897 			if (err)
3898 				goto done;
3899 			resolved = strdup(canonpath);
3900 			if (resolved == NULL) {
3901 				err = got_error_from_errno("strdup");
3902 				goto done;
3903 			}
3904 		}
3905 	}
3906 
3907 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
3908 	    strlen(got_worktree_get_root_path(worktree)))) {
3909 		err = got_error_path(resolved, GOT_ERR_BAD_PATH);
3910 		goto done;
3911 	}
3912 
3913 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
3914 		err = got_path_skip_common_ancestor(&path,
3915 		    got_worktree_get_root_path(worktree), resolved);
3916 		if (err)
3917 			goto done;
3918 	} else {
3919 		path = strdup("");
3920 		if (path == NULL) {
3921 			err = got_error_from_errno("strdup");
3922 			goto done;
3923 		}
3924 	}
3925 
3926 	/* XXX status walk can't deal with trailing slash! */
3927 	len = strlen(path);
3928 	while (len > 0 && path[len - 1] == '/') {
3929 		path[len - 1] = '\0';
3930 		len--;
3931 	}
3932 done:
3933 	free(abspath);
3934 	free(resolved);
3935 	free(cwd);
3936 	if (err == NULL)
3937 		*wt_path = path;
3938 	else
3939 		free(path);
3940 	return err;
3941 }
3942 
3943 struct schedule_addition_args {
3944 	struct got_worktree *worktree;
3945 	struct got_fileindex *fileindex;
3946 	got_worktree_checkout_cb progress_cb;
3947 	void *progress_arg;
3948 	struct got_repository *repo;
3949 };
3950 
3951 static const struct got_error *
3952 schedule_addition(void *arg, unsigned char status, unsigned char staged_status,
3953     const char *relpath, struct got_object_id *blob_id,
3954     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
3955     int dirfd, const char *de_name)
3956 {
3957 	struct schedule_addition_args *a = arg;
3958 	const struct got_error *err = NULL;
3959 	struct got_fileindex_entry *ie;
3960 	struct stat sb;
3961 	char *ondisk_path;
3962 
3963 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
3964 	    relpath) == -1)
3965 		return got_error_from_errno("asprintf");
3966 
3967 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
3968 	if (ie) {
3969 		err = get_file_status(&status, &sb, ie, ondisk_path, dirfd,
3970 		    de_name, a->repo);
3971 		if (err)
3972 			goto done;
3973 		/* Re-adding an existing entry is a no-op. */
3974 		if (status == GOT_STATUS_ADD)
3975 			goto done;
3976 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
3977 		if (err)
3978 			goto done;
3979 	}
3980 
3981 	if (status != GOT_STATUS_UNVERSIONED) {
3982 		if (status == GOT_STATUS_NONEXISTENT)
3983 			err = got_error_set_errno(ENOENT, ondisk_path);
3984 		else
3985 			err = got_error_path(ondisk_path, GOT_ERR_FILE_STATUS);
3986 		goto done;
3987 	}
3988 
3989 	err = got_fileindex_entry_alloc(&ie, relpath);
3990 	if (err)
3991 		goto done;
3992 	err = got_fileindex_entry_update(ie, a->worktree->root_fd,
3993 	    relpath, NULL, NULL, 1);
3994 	if (err) {
3995 		got_fileindex_entry_free(ie);
3996 		goto done;
3997 	}
3998 	err = got_fileindex_entry_add(a->fileindex, ie);
3999 	if (err) {
4000 		got_fileindex_entry_free(ie);
4001 		goto done;
4002 	}
4003 done:
4004 	free(ondisk_path);
4005 	if (err)
4006 		return err;
4007 	if (status == GOT_STATUS_ADD)
4008 		return NULL;
4009 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_ADD, relpath);
4010 }
4011 
4012 const struct got_error *
4013 got_worktree_schedule_add(struct got_worktree *worktree,
4014     struct got_pathlist_head *paths,
4015     got_worktree_checkout_cb progress_cb, void *progress_arg,
4016     struct got_repository *repo, int no_ignores)
4017 {
4018 	struct got_fileindex *fileindex = NULL;
4019 	char *fileindex_path = NULL;
4020 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4021 	struct got_pathlist_entry *pe;
4022 	struct schedule_addition_args saa;
4023 
4024 	err = lock_worktree(worktree, LOCK_EX);
4025 	if (err)
4026 		return err;
4027 
4028 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4029 	if (err)
4030 		goto done;
4031 
4032 	saa.worktree = worktree;
4033 	saa.fileindex = fileindex;
4034 	saa.progress_cb = progress_cb;
4035 	saa.progress_arg = progress_arg;
4036 	saa.repo = repo;
4037 
4038 	TAILQ_FOREACH(pe, paths, entry) {
4039 		err = worktree_status(worktree, pe->path, fileindex, repo,
4040 			schedule_addition, &saa, NULL, NULL, no_ignores, 0);
4041 		if (err)
4042 			break;
4043 	}
4044 	sync_err = sync_fileindex(fileindex, fileindex_path);
4045 	if (sync_err && err == NULL)
4046 		err = sync_err;
4047 done:
4048 	free(fileindex_path);
4049 	if (fileindex)
4050 		got_fileindex_free(fileindex);
4051 	unlockerr = lock_worktree(worktree, LOCK_SH);
4052 	if (unlockerr && err == NULL)
4053 		err = unlockerr;
4054 	return err;
4055 }
4056 
4057 struct schedule_deletion_args {
4058 	struct got_worktree *worktree;
4059 	struct got_fileindex *fileindex;
4060 	got_worktree_delete_cb progress_cb;
4061 	void *progress_arg;
4062 	struct got_repository *repo;
4063 	int delete_local_mods;
4064 	int keep_on_disk;
4065 	int ignore_missing_paths;
4066 	const char *status_codes;
4067 };
4068 
4069 static const struct got_error *
4070 schedule_for_deletion(void *arg, unsigned char status,
4071     unsigned char staged_status, const char *relpath,
4072     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
4073     struct got_object_id *commit_id, int dirfd, const char *de_name)
4074 {
4075 	struct schedule_deletion_args *a = arg;
4076 	const struct got_error *err = NULL;
4077 	struct got_fileindex_entry *ie = NULL;
4078 	struct stat sb;
4079 	char *ondisk_path;
4080 
4081 	if (status == GOT_STATUS_NONEXISTENT) {
4082 		if (a->ignore_missing_paths)
4083 			return NULL;
4084 		return got_error_set_errno(ENOENT, relpath);
4085 	}
4086 
4087 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4088 	if (ie == NULL)
4089 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
4090 
4091 	staged_status = get_staged_status(ie);
4092 	if (staged_status != GOT_STATUS_NO_CHANGE) {
4093 		if (staged_status == GOT_STATUS_DELETE)
4094 			return NULL;
4095 		return got_error_path(relpath, GOT_ERR_FILE_STAGED);
4096 	}
4097 
4098 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
4099 	    relpath) == -1)
4100 		return got_error_from_errno("asprintf");
4101 
4102 	err = get_file_status(&status, &sb, ie, ondisk_path, dirfd, de_name,
4103 	    a->repo);
4104 	if (err)
4105 		goto done;
4106 
4107 	if (a->status_codes) {
4108 		size_t ncodes = strlen(a->status_codes);
4109 		int i;
4110 		for (i = 0; i < ncodes ; i++) {
4111 			if (status == a->status_codes[i])
4112 				break;
4113 		}
4114 		if (i == ncodes) {
4115 			/* Do not delete files in non-matching status. */
4116 			free(ondisk_path);
4117 			return NULL;
4118 		}
4119 		if (a->status_codes[i] != GOT_STATUS_MODIFY &&
4120 		    a->status_codes[i] != GOT_STATUS_MISSING) {
4121 			static char msg[64];
4122 			snprintf(msg, sizeof(msg),
4123 			    "invalid status code '%c'", a->status_codes[i]);
4124 			err = got_error_msg(GOT_ERR_FILE_STATUS, msg);
4125 			goto done;
4126 		}
4127 	}
4128 
4129 	if (status != GOT_STATUS_NO_CHANGE) {
4130 		if (status == GOT_STATUS_DELETE)
4131 			goto done;
4132 		if (status == GOT_STATUS_MODIFY && !a->delete_local_mods) {
4133 			err = got_error_path(relpath, GOT_ERR_FILE_MODIFIED);
4134 			goto done;
4135 		}
4136 		if (status == GOT_STATUS_MISSING && !a->ignore_missing_paths) {
4137 			err = got_error_set_errno(ENOENT, relpath);
4138 			goto done;
4139 		}
4140 		if (status != GOT_STATUS_MODIFY &&
4141 		    status != GOT_STATUS_MISSING) {
4142 			err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4143 			goto done;
4144 		}
4145 	}
4146 
4147 	if (!a->keep_on_disk && status != GOT_STATUS_MISSING) {
4148 		size_t root_len;
4149 
4150 		if (dirfd != -1) {
4151 			if (unlinkat(dirfd, de_name, 0) == -1) {
4152 				err = got_error_from_errno2("unlinkat",
4153 				    ondisk_path);
4154 				goto done;
4155 			}
4156 		} else if (unlink(ondisk_path) == -1) {
4157 			err = got_error_from_errno2("unlink", ondisk_path);
4158 			goto done;
4159 		}
4160 
4161 		root_len = strlen(a->worktree->root_path);
4162 		do {
4163 			char *parent;
4164 			err = got_path_dirname(&parent, ondisk_path);
4165 			if (err)
4166 				goto done;
4167 			free(ondisk_path);
4168 			ondisk_path = parent;
4169 			if (rmdir(ondisk_path) == -1) {
4170 				if (errno != ENOTEMPTY)
4171 					err = got_error_from_errno2("rmdir",
4172 					    ondisk_path);
4173 				break;
4174 			}
4175 		} while (got_path_cmp(ondisk_path, a->worktree->root_path,
4176 		    strlen(ondisk_path), root_len) != 0);
4177 	}
4178 
4179 	got_fileindex_entry_mark_deleted_from_disk(ie);
4180 done:
4181 	free(ondisk_path);
4182 	if (err)
4183 		return err;
4184 	if (status == GOT_STATUS_DELETE)
4185 		return NULL;
4186 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
4187 	    staged_status, relpath);
4188 }
4189 
4190 const struct got_error *
4191 got_worktree_schedule_delete(struct got_worktree *worktree,
4192     struct got_pathlist_head *paths, int delete_local_mods,
4193     const char *status_codes,
4194     got_worktree_delete_cb progress_cb, void *progress_arg,
4195     struct got_repository *repo, int keep_on_disk, int ignore_missing_paths)
4196 {
4197 	struct got_fileindex *fileindex = NULL;
4198 	char *fileindex_path = NULL;
4199 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4200 	struct got_pathlist_entry *pe;
4201 	struct schedule_deletion_args sda;
4202 
4203 	err = lock_worktree(worktree, LOCK_EX);
4204 	if (err)
4205 		return err;
4206 
4207 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4208 	if (err)
4209 		goto done;
4210 
4211 	sda.worktree = worktree;
4212 	sda.fileindex = fileindex;
4213 	sda.progress_cb = progress_cb;
4214 	sda.progress_arg = progress_arg;
4215 	sda.repo = repo;
4216 	sda.delete_local_mods = delete_local_mods;
4217 	sda.keep_on_disk = keep_on_disk;
4218 	sda.ignore_missing_paths = ignore_missing_paths;
4219 	sda.status_codes = status_codes;
4220 
4221 	TAILQ_FOREACH(pe, paths, entry) {
4222 		err = worktree_status(worktree, pe->path, fileindex, repo,
4223 			schedule_for_deletion, &sda, NULL, NULL, 1, 1);
4224 		if (err)
4225 			break;
4226 	}
4227 	sync_err = sync_fileindex(fileindex, fileindex_path);
4228 	if (sync_err && err == NULL)
4229 		err = sync_err;
4230 done:
4231 	free(fileindex_path);
4232 	if (fileindex)
4233 		got_fileindex_free(fileindex);
4234 	unlockerr = lock_worktree(worktree, LOCK_SH);
4235 	if (unlockerr && err == NULL)
4236 		err = unlockerr;
4237 	return err;
4238 }
4239 
4240 static const struct got_error *
4241 copy_one_line(FILE *infile, FILE *outfile, FILE *rejectfile)
4242 {
4243 	const struct got_error *err = NULL;
4244 	char *line = NULL;
4245 	size_t linesize = 0, n;
4246 	ssize_t linelen;
4247 
4248 	linelen = getline(&line, &linesize, infile);
4249 	if (linelen == -1) {
4250 		if (ferror(infile)) {
4251 			err = got_error_from_errno("getline");
4252 			goto done;
4253 		}
4254 		return NULL;
4255 	}
4256 	if (outfile) {
4257 		n = fwrite(line, 1, linelen, outfile);
4258 		if (n != linelen) {
4259 			err = got_ferror(outfile, GOT_ERR_IO);
4260 			goto done;
4261 		}
4262 	}
4263 	if (rejectfile) {
4264 		n = fwrite(line, 1, linelen, rejectfile);
4265 		if (n != linelen)
4266 			err = got_ferror(outfile, GOT_ERR_IO);
4267 	}
4268 done:
4269 	free(line);
4270 	return err;
4271 }
4272 
4273 static const struct got_error *
4274 skip_one_line(FILE *f)
4275 {
4276 	char *line = NULL;
4277 	size_t linesize = 0;
4278 	ssize_t linelen;
4279 
4280 	linelen = getline(&line, &linesize, f);
4281 	if (linelen == -1) {
4282 		if (ferror(f))
4283 			return got_error_from_errno("getline");
4284 		return NULL;
4285 	}
4286 	free(line);
4287 	return NULL;
4288 }
4289 
4290 static const struct got_error *
4291 copy_change(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4292     int start_old, int end_old, int start_new, int end_new,
4293     FILE *outfile, FILE *rejectfile)
4294 {
4295 	const struct got_error *err;
4296 
4297 	/* Copy old file's lines leading up to patch. */
4298 	while (!feof(f1) && *line_cur1 < start_old) {
4299 		err = copy_one_line(f1, outfile, NULL);
4300 		if (err)
4301 			return err;
4302 		(*line_cur1)++;
4303 	}
4304 	/* Skip new file's lines leading up to patch. */
4305 	while (!feof(f2) && *line_cur2 < start_new) {
4306 		if (rejectfile)
4307 			err = copy_one_line(f2, NULL, rejectfile);
4308 		else
4309 			err = skip_one_line(f2);
4310 		if (err)
4311 			return err;
4312 		(*line_cur2)++;
4313 	}
4314 	/* Copy patched lines. */
4315 	while (!feof(f2) && *line_cur2 <= end_new) {
4316 		err = copy_one_line(f2, outfile, NULL);
4317 		if (err)
4318 			return err;
4319 		(*line_cur2)++;
4320 	}
4321 	/* Skip over old file's replaced lines. */
4322 	while (!feof(f1) && *line_cur1 <= end_old) {
4323 		if (rejectfile)
4324 			err = copy_one_line(f1, NULL, rejectfile);
4325 		else
4326 			err = skip_one_line(f1);
4327 		if (err)
4328 			return err;
4329 		(*line_cur1)++;
4330 	}
4331 
4332 	return NULL;
4333 }
4334 
4335 static const struct got_error *
4336 copy_remaining_content(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4337     FILE *outfile, FILE *rejectfile)
4338 {
4339 	const struct got_error *err;
4340 
4341 	if (outfile) {
4342 		/* Copy old file's lines until EOF. */
4343 		while (!feof(f1)) {
4344 			err = copy_one_line(f1, outfile, NULL);
4345 			if (err)
4346 				return err;
4347 			(*line_cur1)++;
4348 		}
4349 	}
4350 	if (rejectfile) {
4351 		/* Copy new file's lines until EOF. */
4352 		while (!feof(f2)) {
4353 			err = copy_one_line(f2, NULL, rejectfile);
4354 			if (err)
4355 				return err;
4356 			(*line_cur2)++;
4357 		}
4358 	}
4359 
4360 	return NULL;
4361 }
4362 
4363 static const struct got_error *
4364 apply_or_reject_change(int *choice, int *nchunks_used,
4365     struct diff_result *diff_result, int n,
4366     const char *relpath, FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4367     FILE *outfile, FILE *rejectfile, int changeno, int nchanges,
4368     got_worktree_patch_cb patch_cb, void *patch_arg)
4369 {
4370 	const struct got_error *err = NULL;
4371 	struct diff_chunk_context cc = {};
4372 	int start_old, end_old, start_new, end_new;
4373 	FILE *hunkfile;
4374 	struct diff_output_unidiff_state *diff_state;
4375 	struct diff_input_info diff_info;
4376 	int rc;
4377 
4378 	*choice = GOT_PATCH_CHOICE_NONE;
4379 
4380 	/* Get changed line numbers without context lines for copy_change(). */
4381 	diff_chunk_context_load_change(&cc, NULL, diff_result, n, 0);
4382 	start_old = cc.left.start;
4383 	end_old = cc.left.end;
4384 	start_new = cc.right.start;
4385 	end_new = cc.right.end;
4386 
4387 	/* Get the same change with context lines for display. */
4388 	memset(&cc, 0, sizeof(cc));
4389 	diff_chunk_context_load_change(&cc, nchunks_used, diff_result, n, 3);
4390 
4391 	memset(&diff_info, 0, sizeof(diff_info));
4392 	diff_info.left_path = relpath;
4393 	diff_info.right_path = relpath;
4394 
4395 	diff_state = diff_output_unidiff_state_alloc();
4396 	if (diff_state == NULL)
4397 		return got_error_set_errno(ENOMEM,
4398 		    "diff_output_unidiff_state_alloc");
4399 
4400 	hunkfile = got_opentemp();
4401 	if (hunkfile == NULL) {
4402 		err = got_error_from_errno("got_opentemp");
4403 		goto done;
4404 	}
4405 
4406 	rc = diff_output_unidiff_chunk(NULL, hunkfile, diff_state, &diff_info,
4407 	    diff_result, &cc);
4408 	if (rc != DIFF_RC_OK) {
4409 		err = got_error_set_errno(rc, "diff_output_unidiff_chunk");
4410 		goto done;
4411 	}
4412 
4413 	if (fseek(hunkfile, 0L, SEEK_SET) == -1) {
4414 		err = got_ferror(hunkfile, GOT_ERR_IO);
4415 		goto done;
4416 	}
4417 
4418 	err = (*patch_cb)(choice, patch_arg, GOT_STATUS_MODIFY, relpath,
4419 	    hunkfile, changeno, nchanges);
4420 	if (err)
4421 		goto done;
4422 
4423 	switch (*choice) {
4424 	case GOT_PATCH_CHOICE_YES:
4425 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4426 		    end_old, start_new, end_new, outfile, rejectfile);
4427 		break;
4428 	case GOT_PATCH_CHOICE_NO:
4429 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4430 		    end_old, start_new, end_new, rejectfile, outfile);
4431 		break;
4432 	case GOT_PATCH_CHOICE_QUIT:
4433 		break;
4434 	default:
4435 		err = got_error(GOT_ERR_PATCH_CHOICE);
4436 		break;
4437 	}
4438 done:
4439 	diff_output_unidiff_state_free(diff_state);
4440 	if (hunkfile && fclose(hunkfile) == EOF && err == NULL)
4441 		err = got_error_from_errno("fclose");
4442 	return err;
4443 }
4444 
4445 struct revert_file_args {
4446 	struct got_worktree *worktree;
4447 	struct got_fileindex *fileindex;
4448 	got_worktree_checkout_cb progress_cb;
4449 	void *progress_arg;
4450 	got_worktree_patch_cb patch_cb;
4451 	void *patch_arg;
4452 	struct got_repository *repo;
4453 	int unlink_added_files;
4454 };
4455 
4456 static const struct got_error *
4457 create_patched_content(char **path_outfile, int reverse_patch,
4458     struct got_object_id *blob_id, const char *path2,
4459     int dirfd2, const char *de_name2,
4460     const char *relpath, struct got_repository *repo,
4461     got_worktree_patch_cb patch_cb, void *patch_arg)
4462 {
4463 	const struct got_error *err, *free_err;
4464 	struct got_blob_object *blob = NULL;
4465 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL;
4466 	int fd = -1, fd2 = -1;
4467 	char link_target[PATH_MAX];
4468 	ssize_t link_len = 0;
4469 	char *path1 = NULL, *id_str = NULL;
4470 	struct stat sb2;
4471 	struct got_diffreg_result *diffreg_result = NULL;
4472 	int line_cur1 = 1, line_cur2 = 1, have_content = 0;
4473 	int i = 0, n = 0, nchunks_used = 0, nchanges = 0;
4474 
4475 	*path_outfile = NULL;
4476 
4477 	err = got_object_id_str(&id_str, blob_id);
4478 	if (err)
4479 		return err;
4480 
4481 	if (dirfd2 != -1) {
4482 		fd2 = openat(dirfd2, de_name2,
4483 		    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
4484 		if (fd2 == -1) {
4485 			if (!got_err_open_nofollow_on_symlink()) {
4486 				err = got_error_from_errno2("openat", path2);
4487 				goto done;
4488 			}
4489 			link_len = readlinkat(dirfd2, de_name2,
4490 			    link_target, sizeof(link_target));
4491 			if (link_len == -1) {
4492 				return got_error_from_errno2("readlinkat",
4493 				    path2);
4494 			}
4495 			sb2.st_mode = S_IFLNK;
4496 			sb2.st_size = link_len;
4497 		}
4498 	} else {
4499 		fd2 = open(path2, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
4500 		if (fd2 == -1) {
4501 			if (!got_err_open_nofollow_on_symlink()) {
4502 				err = got_error_from_errno2("open", path2);
4503 				goto done;
4504 			}
4505 			link_len = readlink(path2, link_target,
4506 			    sizeof(link_target));
4507 			if (link_len == -1)
4508 				return got_error_from_errno2("readlink", path2);
4509 			sb2.st_mode = S_IFLNK;
4510 			sb2.st_size = link_len;
4511 		}
4512 	}
4513 	if (fd2 != -1) {
4514 		if (fstat(fd2, &sb2) == -1) {
4515 			err = got_error_from_errno2("fstat", path2);
4516 			goto done;
4517 		}
4518 
4519 		f2 = fdopen(fd2, "r");
4520 		if (f2 == NULL) {
4521 			err = got_error_from_errno2("fdopen", path2);
4522 			goto done;
4523 		}
4524 		fd2 = -1;
4525 	} else {
4526 		size_t n;
4527 		f2 = got_opentemp();
4528 		if (f2 == NULL) {
4529 			err = got_error_from_errno2("got_opentemp", path2);
4530 			goto done;
4531 		}
4532 		n = fwrite(link_target, 1, link_len, f2);
4533 		if (n != link_len) {
4534 			err = got_ferror(f2, GOT_ERR_IO);
4535 			goto done;
4536 		}
4537 		if (fflush(f2) == EOF) {
4538 			err = got_error_from_errno("fflush");
4539 			goto done;
4540 		}
4541 		rewind(f2);
4542 	}
4543 
4544 	fd = got_opentempfd();
4545 	if (fd == -1) {
4546 		err = got_error_from_errno("got_opentempfd");
4547 		goto done;
4548 	}
4549 
4550 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192, fd);
4551 	if (err)
4552 		goto done;
4553 
4554 	err = got_opentemp_named(&path1, &f1, "got-patched-blob", "");
4555 	if (err)
4556 		goto done;
4557 
4558 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
4559 	if (err)
4560 		goto done;
4561 
4562 	err = got_diff_files(&diffreg_result, f1, 1, id_str, f2, 1, path2,
4563 	    3, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
4564 	if (err)
4565 		goto done;
4566 
4567 	err = got_opentemp_named(path_outfile, &outfile, "got-patched-content",
4568 	    "");
4569 	if (err)
4570 		goto done;
4571 
4572 	if (fseek(f1, 0L, SEEK_SET) == -1)
4573 		return got_ferror(f1, GOT_ERR_IO);
4574 	if (fseek(f2, 0L, SEEK_SET) == -1)
4575 		return got_ferror(f2, GOT_ERR_IO);
4576 
4577 	/* Count the number of actual changes in the diff result. */
4578 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4579 		struct diff_chunk_context cc = {};
4580 		diff_chunk_context_load_change(&cc, &nchunks_used,
4581 		    diffreg_result->result, n, 0);
4582 		nchanges++;
4583 	}
4584 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4585 		int choice;
4586 		err = apply_or_reject_change(&choice, &nchunks_used,
4587 		    diffreg_result->result, n, relpath, f1, f2,
4588 		    &line_cur1, &line_cur2,
4589 		    reverse_patch ? NULL : outfile,
4590 		    reverse_patch ? outfile : NULL,
4591 		    ++i, nchanges, patch_cb, patch_arg);
4592 		if (err)
4593 			goto done;
4594 		if (choice == GOT_PATCH_CHOICE_YES)
4595 			have_content = 1;
4596 		else if (choice == GOT_PATCH_CHOICE_QUIT)
4597 			break;
4598 	}
4599 	if (have_content) {
4600 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
4601 		    reverse_patch ? NULL : outfile,
4602 		    reverse_patch ? outfile : NULL);
4603 		if (err)
4604 			goto done;
4605 
4606 		if (!S_ISLNK(sb2.st_mode)) {
4607 			mode_t mode;
4608 
4609 			mode = apply_umask(sb2.st_mode);
4610 			if (fchmod(fileno(outfile), mode) == -1) {
4611 				err = got_error_from_errno2("fchmod", path2);
4612 				goto done;
4613 			}
4614 		}
4615 	}
4616 done:
4617 	free(id_str);
4618 	if (fd != -1 && close(fd) == -1 && err == NULL)
4619 		err = got_error_from_errno("close");
4620 	if (blob)
4621 		got_object_blob_close(blob);
4622 	free_err = got_diffreg_result_free(diffreg_result);
4623 	if (err == NULL)
4624 		err = free_err;
4625 	if (f1 && fclose(f1) == EOF && err == NULL)
4626 		err = got_error_from_errno2("fclose", path1);
4627 	if (f2 && fclose(f2) == EOF && err == NULL)
4628 		err = got_error_from_errno2("fclose", path2);
4629 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
4630 		err = got_error_from_errno2("close", path2);
4631 	if (outfile && fclose(outfile) == EOF && err == NULL)
4632 		err = got_error_from_errno2("fclose", *path_outfile);
4633 	if (path1 && unlink(path1) == -1 && err == NULL)
4634 		err = got_error_from_errno2("unlink", path1);
4635 	if (err || !have_content) {
4636 		if (*path_outfile && unlink(*path_outfile) == -1 && err == NULL)
4637 			err = got_error_from_errno2("unlink", *path_outfile);
4638 		free(*path_outfile);
4639 		*path_outfile = NULL;
4640 	}
4641 	free(path1);
4642 	return err;
4643 }
4644 
4645 static const struct got_error *
4646 revert_file(void *arg, unsigned char status, unsigned char staged_status,
4647     const char *relpath, struct got_object_id *blob_id,
4648     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
4649     int dirfd, const char *de_name)
4650 {
4651 	struct revert_file_args *a = arg;
4652 	const struct got_error *err = NULL;
4653 	char *parent_path = NULL;
4654 	struct got_fileindex_entry *ie;
4655 	struct got_commit_object *base_commit = NULL;
4656 	struct got_tree_object *tree = NULL;
4657 	struct got_object_id *tree_id = NULL;
4658 	const struct got_tree_entry *te = NULL;
4659 	char *tree_path = NULL, *te_name;
4660 	char *ondisk_path = NULL, *path_content = NULL;
4661 	struct got_blob_object *blob = NULL;
4662 	int fd = -1;
4663 
4664 	/* Reverting a staged deletion is a no-op. */
4665 	if (status == GOT_STATUS_DELETE &&
4666 	    staged_status != GOT_STATUS_NO_CHANGE)
4667 		return NULL;
4668 
4669 	if (status == GOT_STATUS_UNVERSIONED)
4670 		return (*a->progress_cb)(a->progress_arg,
4671 		    GOT_STATUS_UNVERSIONED, relpath);
4672 
4673 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4674 	if (ie == NULL)
4675 		return got_error_path(relpath, GOT_ERR_BAD_PATH);
4676 
4677 	/* Construct in-repository path of tree which contains this blob. */
4678 	err = got_path_dirname(&parent_path, ie->path);
4679 	if (err) {
4680 		if (err->code != GOT_ERR_BAD_PATH)
4681 			goto done;
4682 		parent_path = strdup("/");
4683 		if (parent_path == NULL) {
4684 			err = got_error_from_errno("strdup");
4685 			goto done;
4686 		}
4687 	}
4688 	if (got_path_is_root_dir(a->worktree->path_prefix)) {
4689 		tree_path = strdup(parent_path);
4690 		if (tree_path == NULL) {
4691 			err = got_error_from_errno("strdup");
4692 			goto done;
4693 		}
4694 	} else {
4695 		if (got_path_is_root_dir(parent_path)) {
4696 			tree_path = strdup(a->worktree->path_prefix);
4697 			if (tree_path == NULL) {
4698 				err = got_error_from_errno("strdup");
4699 				goto done;
4700 			}
4701 		} else {
4702 			if (asprintf(&tree_path, "%s/%s",
4703 			    a->worktree->path_prefix, parent_path) == -1) {
4704 				err = got_error_from_errno("asprintf");
4705 				goto done;
4706 			}
4707 		}
4708 	}
4709 
4710 	err = got_object_open_as_commit(&base_commit, a->repo,
4711 	    a->worktree->base_commit_id);
4712 	if (err)
4713 		goto done;
4714 
4715 	err = got_object_id_by_path(&tree_id, a->repo, base_commit, tree_path);
4716 	if (err) {
4717 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
4718 		    (status == GOT_STATUS_ADD ||
4719 		    staged_status == GOT_STATUS_ADD)))
4720 			goto done;
4721 	} else {
4722 		err = got_object_open_as_tree(&tree, a->repo, tree_id);
4723 		if (err)
4724 			goto done;
4725 
4726 		err = got_path_basename(&te_name, ie->path);
4727 		if (err)
4728 			goto done;
4729 
4730 		te = got_object_tree_find_entry(tree, te_name);
4731 		free(te_name);
4732 		if (te == NULL && status != GOT_STATUS_ADD &&
4733 		    staged_status != GOT_STATUS_ADD) {
4734 			err = got_error_path(ie->path, GOT_ERR_NO_TREE_ENTRY);
4735 			goto done;
4736 		}
4737 	}
4738 
4739 	switch (status) {
4740 	case GOT_STATUS_ADD:
4741 		if (a->patch_cb) {
4742 			int choice = GOT_PATCH_CHOICE_NONE;
4743 			err = (*a->patch_cb)(&choice, a->patch_arg,
4744 			    status, ie->path, NULL, 1, 1);
4745 			if (err)
4746 				goto done;
4747 			if (choice != GOT_PATCH_CHOICE_YES)
4748 				break;
4749 		}
4750 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_REVERT,
4751 		    ie->path);
4752 		if (err)
4753 			goto done;
4754 		got_fileindex_entry_remove(a->fileindex, ie);
4755 		if (a->unlink_added_files) {
4756 			if (asprintf(&ondisk_path, "%s/%s",
4757 			    got_worktree_get_root_path(a->worktree),
4758 			    relpath) == -1) {
4759 				err = got_error_from_errno("asprintf");
4760 				goto done;
4761 			}
4762 			if (unlink(ondisk_path) == -1) {
4763 				err = got_error_from_errno2("unlink",
4764 				    ondisk_path);
4765 				break;
4766 			}
4767 		}
4768 		break;
4769 	case GOT_STATUS_DELETE:
4770 		if (a->patch_cb) {
4771 			int choice = GOT_PATCH_CHOICE_NONE;
4772 			err = (*a->patch_cb)(&choice, a->patch_arg,
4773 			    status, ie->path, NULL, 1, 1);
4774 			if (err)
4775 				goto done;
4776 			if (choice != GOT_PATCH_CHOICE_YES)
4777 				break;
4778 		}
4779 		/* fall through */
4780 	case GOT_STATUS_MODIFY:
4781 	case GOT_STATUS_MODE_CHANGE:
4782 	case GOT_STATUS_CONFLICT:
4783 	case GOT_STATUS_MISSING: {
4784 		struct got_object_id id;
4785 		if (staged_status == GOT_STATUS_ADD ||
4786 		    staged_status == GOT_STATUS_MODIFY) {
4787 			memcpy(id.sha1, ie->staged_blob_sha1,
4788 			    SHA1_DIGEST_LENGTH);
4789 		} else
4790 			memcpy(id.sha1, ie->blob_sha1,
4791 			    SHA1_DIGEST_LENGTH);
4792 		fd = got_opentempfd();
4793 		if (fd == -1) {
4794 			err = got_error_from_errno("got_opentempfd");
4795 			goto done;
4796 		}
4797 
4798 		err = got_object_open_as_blob(&blob, a->repo, &id, 8192, fd);
4799 		if (err)
4800 			goto done;
4801 
4802 		if (asprintf(&ondisk_path, "%s/%s",
4803 		    got_worktree_get_root_path(a->worktree), relpath) == -1) {
4804 			err = got_error_from_errno("asprintf");
4805 			goto done;
4806 		}
4807 
4808 		if (a->patch_cb && (status == GOT_STATUS_MODIFY ||
4809 		    status == GOT_STATUS_CONFLICT)) {
4810 			int is_bad_symlink = 0;
4811 			err = create_patched_content(&path_content, 1, &id,
4812 			    ondisk_path, dirfd, de_name, ie->path, a->repo,
4813 			    a->patch_cb, a->patch_arg);
4814 			if (err || path_content == NULL)
4815 				break;
4816 			if (te && S_ISLNK(te->mode)) {
4817 				if (unlink(path_content) == -1) {
4818 					err = got_error_from_errno2("unlink",
4819 					    path_content);
4820 					break;
4821 				}
4822 				err = install_symlink(&is_bad_symlink,
4823 				    a->worktree, ondisk_path, ie->path,
4824 				    blob, 0, 1, 0, 0, a->repo,
4825 				    a->progress_cb, a->progress_arg);
4826 			} else {
4827 				if (rename(path_content, ondisk_path) == -1) {
4828 					err = got_error_from_errno3("rename",
4829 					    path_content, ondisk_path);
4830 					goto done;
4831 				}
4832 			}
4833 		} else {
4834 			int is_bad_symlink = 0;
4835 			if (te && S_ISLNK(te->mode)) {
4836 				err = install_symlink(&is_bad_symlink,
4837 				    a->worktree, ondisk_path, ie->path,
4838 				    blob, 0, 1, 0, 0, a->repo,
4839 				    a->progress_cb, a->progress_arg);
4840 			} else {
4841 				err = install_blob(a->worktree, ondisk_path,
4842 				    ie->path,
4843 				    te ? te->mode : GOT_DEFAULT_FILE_MODE,
4844 				    got_fileindex_perms_to_st(ie), blob,
4845 				    0, 1, 0, 0, a->repo,
4846 				    a->progress_cb, a->progress_arg);
4847 			}
4848 			if (err)
4849 				goto done;
4850 			if (status == GOT_STATUS_DELETE ||
4851 			    status == GOT_STATUS_MODE_CHANGE) {
4852 				err = got_fileindex_entry_update(ie,
4853 				    a->worktree->root_fd, relpath,
4854 				    blob->id.sha1,
4855 				    a->worktree->base_commit_id->sha1, 1);
4856 				if (err)
4857 					goto done;
4858 			}
4859 			if (is_bad_symlink) {
4860 				got_fileindex_entry_filetype_set(ie,
4861 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
4862 			}
4863 		}
4864 		break;
4865 	}
4866 	default:
4867 		break;
4868 	}
4869 done:
4870 	free(ondisk_path);
4871 	free(path_content);
4872 	free(parent_path);
4873 	free(tree_path);
4874 	if (fd != -1 && close(fd) == -1 && err == NULL)
4875 		err = got_error_from_errno("close");
4876 	if (blob)
4877 		got_object_blob_close(blob);
4878 	if (tree)
4879 		got_object_tree_close(tree);
4880 	free(tree_id);
4881 	if (base_commit)
4882 		got_object_commit_close(base_commit);
4883 	return err;
4884 }
4885 
4886 const struct got_error *
4887 got_worktree_revert(struct got_worktree *worktree,
4888     struct got_pathlist_head *paths,
4889     got_worktree_checkout_cb progress_cb, void *progress_arg,
4890     got_worktree_patch_cb patch_cb, void *patch_arg,
4891     struct got_repository *repo)
4892 {
4893 	struct got_fileindex *fileindex = NULL;
4894 	char *fileindex_path = NULL;
4895 	const struct got_error *err = NULL, *unlockerr = NULL;
4896 	const struct got_error *sync_err = NULL;
4897 	struct got_pathlist_entry *pe;
4898 	struct revert_file_args rfa;
4899 
4900 	err = lock_worktree(worktree, LOCK_EX);
4901 	if (err)
4902 		return err;
4903 
4904 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4905 	if (err)
4906 		goto done;
4907 
4908 	rfa.worktree = worktree;
4909 	rfa.fileindex = fileindex;
4910 	rfa.progress_cb = progress_cb;
4911 	rfa.progress_arg = progress_arg;
4912 	rfa.patch_cb = patch_cb;
4913 	rfa.patch_arg = patch_arg;
4914 	rfa.repo = repo;
4915 	rfa.unlink_added_files = 0;
4916 	TAILQ_FOREACH(pe, paths, entry) {
4917 		err = worktree_status(worktree, pe->path, fileindex, repo,
4918 		    revert_file, &rfa, NULL, NULL, 1, 0);
4919 		if (err)
4920 			break;
4921 	}
4922 	sync_err = sync_fileindex(fileindex, fileindex_path);
4923 	if (sync_err && err == NULL)
4924 		err = sync_err;
4925 done:
4926 	free(fileindex_path);
4927 	if (fileindex)
4928 		got_fileindex_free(fileindex);
4929 	unlockerr = lock_worktree(worktree, LOCK_SH);
4930 	if (unlockerr && err == NULL)
4931 		err = unlockerr;
4932 	return err;
4933 }
4934 
4935 static void
4936 free_commitable(struct got_commitable *ct)
4937 {
4938 	free(ct->path);
4939 	free(ct->in_repo_path);
4940 	free(ct->ondisk_path);
4941 	free(ct->blob_id);
4942 	free(ct->base_blob_id);
4943 	free(ct->staged_blob_id);
4944 	free(ct->base_commit_id);
4945 	free(ct);
4946 }
4947 
4948 struct collect_commitables_arg {
4949 	struct got_pathlist_head *commitable_paths;
4950 	struct got_repository *repo;
4951 	struct got_worktree *worktree;
4952 	struct got_fileindex *fileindex;
4953 	int have_staged_files;
4954 	int allow_bad_symlinks;
4955 	int diff_header_shown;
4956 	FILE *diff_outfile;
4957 	FILE *f1;
4958 	FILE *f2;
4959 };
4960 
4961 /*
4962  * Create a file which contains the target path of a symlink so we can feed
4963  * it as content to the diff engine.
4964  */
4965 static const struct got_error *
4966 get_symlink_target_file(int *fd, int dirfd, const char *de_name,
4967     const char *abspath)
4968 {
4969 	const struct got_error *err = NULL;
4970 	char target_path[PATH_MAX];
4971 	ssize_t target_len, outlen;
4972 
4973 	*fd = -1;
4974 
4975 	if (dirfd != -1) {
4976 		target_len = readlinkat(dirfd, de_name, target_path, PATH_MAX);
4977 		if (target_len == -1)
4978 			return got_error_from_errno2("readlinkat", abspath);
4979 	} else {
4980 		target_len = readlink(abspath, target_path, PATH_MAX);
4981 		if (target_len == -1)
4982 			return got_error_from_errno2("readlink", abspath);
4983 	}
4984 
4985 	*fd = got_opentempfd();
4986 	if (*fd == -1)
4987 		return got_error_from_errno("got_opentempfd");
4988 
4989 	outlen = write(*fd, target_path, target_len);
4990 	if (outlen == -1) {
4991 		err = got_error_from_errno("got_opentempfd");
4992 		goto done;
4993 	}
4994 
4995 	if (lseek(*fd, 0, SEEK_SET) == -1) {
4996 		err = got_error_from_errno2("lseek", abspath);
4997 		goto done;
4998 	}
4999 done:
5000 	if (err) {
5001 		close(*fd);
5002 		*fd = -1;
5003 	}
5004 	return err;
5005 }
5006 
5007 static const struct got_error *
5008 append_ct_diff(struct got_commitable *ct, int *diff_header_shown,
5009     FILE *diff_outfile, FILE *f1, FILE *f2, int dirfd, const char *de_name,
5010     int diff_staged, struct got_repository *repo, struct got_worktree *worktree)
5011 {
5012 	const struct got_error *err = NULL;
5013 	struct got_blob_object *blob1 = NULL;
5014 	int fd = -1, fd1 = -1, fd2 = -1;
5015 	FILE *ondisk_file = NULL;
5016 	char *label1 = NULL;
5017 	struct stat sb;
5018 	off_t size1 = 0;
5019 	int f2_exists = 0;
5020 	char *id_str = NULL;
5021 
5022 	memset(&sb, 0, sizeof(sb));
5023 
5024 	if (diff_staged) {
5025 		if (ct->staged_status != GOT_STATUS_MODIFY &&
5026 		    ct->staged_status != GOT_STATUS_ADD &&
5027 		    ct->staged_status != GOT_STATUS_DELETE)
5028 			return NULL;
5029 	} else {
5030 		if (ct->status != GOT_STATUS_MODIFY &&
5031 		    ct->status != GOT_STATUS_ADD &&
5032 		    ct->status != GOT_STATUS_DELETE)
5033 			return NULL;
5034 	}
5035 
5036 	err = got_opentemp_truncate(f1);
5037 	if (err)
5038 		return got_error_from_errno("got_opentemp_truncate");
5039 	err = got_opentemp_truncate(f2);
5040 	if (err)
5041 		return got_error_from_errno("got_opentemp_truncate");
5042 
5043 	if (!*diff_header_shown) {
5044 		err = got_object_id_str(&id_str, worktree->base_commit_id);
5045 		if (err)
5046 			return err;
5047 		fprintf(diff_outfile, "diff %s%s\n", diff_staged ? "-s " : "",
5048 		    got_worktree_get_root_path(worktree));
5049 		fprintf(diff_outfile, "commit - %s\n", id_str);
5050 		fprintf(diff_outfile, "path + %s%s\n",
5051 		    got_worktree_get_root_path(worktree),
5052 		    diff_staged ? " (staged changes)" : "");
5053 		*diff_header_shown = 1;
5054 	}
5055 
5056 	if (diff_staged) {
5057 		const char *label1 = NULL, *label2 = NULL;
5058 		switch (ct->staged_status) {
5059 		case GOT_STATUS_MODIFY:
5060 			label1 = ct->path;
5061 			label2 = ct->path;
5062 			break;
5063 		case GOT_STATUS_ADD:
5064 			label2 = ct->path;
5065 			break;
5066 		case GOT_STATUS_DELETE:
5067 			label1 = ct->path;
5068 			break;
5069 		default:
5070 			return got_error(GOT_ERR_FILE_STATUS);
5071 		}
5072 		fd1 = got_opentempfd();
5073 		if (fd1 == -1) {
5074 			err = got_error_from_errno("got_opentempfd");
5075 			goto done;
5076 		}
5077 		fd2 = got_opentempfd();
5078 		if (fd2 == -1) {
5079 			err = got_error_from_errno("got_opentempfd");
5080 			goto done;
5081 		}
5082 		err = got_diff_objects_as_blobs(NULL, NULL, f1, f2,
5083 		    fd1, fd2, ct->base_blob_id, ct->staged_blob_id,
5084 		    label1, label2, GOT_DIFF_ALGORITHM_PATIENCE, 3, 0, 0,
5085 		    repo, diff_outfile);
5086 		goto done;
5087 	}
5088 
5089 	fd1 = got_opentempfd();
5090 	if (fd1 == -1) {
5091 		err = got_error_from_errno("got_opentempfd");
5092 		goto done;
5093 	}
5094 
5095 	if (ct->status != GOT_STATUS_ADD) {
5096 		err = got_object_open_as_blob(&blob1, repo, ct->base_blob_id,
5097 		    8192, fd1);
5098 		if (err)
5099 			goto done;
5100 	}
5101 
5102 	if (ct->status != GOT_STATUS_DELETE) {
5103 		if (dirfd != -1) {
5104 			fd = openat(dirfd, de_name,
5105 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
5106 			if (fd == -1) {
5107 				if (!got_err_open_nofollow_on_symlink()) {
5108 					err = got_error_from_errno2("openat",
5109 					    ct->ondisk_path);
5110 					goto done;
5111 				}
5112 				err = get_symlink_target_file(&fd, dirfd,
5113 				    de_name, ct->ondisk_path);
5114 				if (err)
5115 					goto done;
5116 			}
5117 		} else {
5118 			fd = open(ct->ondisk_path,
5119 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
5120 			if (fd == -1) {
5121 				if (!got_err_open_nofollow_on_symlink()) {
5122 					err = got_error_from_errno2("open",
5123 					    ct->ondisk_path);
5124 					goto done;
5125 				}
5126 				err = get_symlink_target_file(&fd, dirfd,
5127 				    de_name, ct->ondisk_path);
5128 				if (err)
5129 					goto done;
5130 			}
5131 		}
5132 		if (fstatat(fd, ct->ondisk_path, &sb,
5133 		    AT_SYMLINK_NOFOLLOW) == -1) {
5134 			err = got_error_from_errno2("fstatat", ct->ondisk_path);
5135 			goto done;
5136 		}
5137 		ondisk_file = fdopen(fd, "r");
5138 		if (ondisk_file == NULL) {
5139 			err = got_error_from_errno2("fdopen", ct->ondisk_path);
5140 			goto done;
5141 		}
5142 		fd = -1;
5143 		f2_exists = 1;
5144 	}
5145 
5146 	if (blob1) {
5147 		err = got_object_blob_dump_to_file(&size1, NULL, NULL,
5148 		    f1, blob1);
5149 		if (err)
5150 			goto done;
5151 	}
5152 
5153 	err = got_diff_blob_file(blob1, f1, size1, label1,
5154 	    ondisk_file ? ondisk_file : f2, f2_exists, &sb, ct->path,
5155 	    GOT_DIFF_ALGORITHM_PATIENCE, 3, 0, 0, diff_outfile);
5156 done:
5157 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
5158 		err = got_error_from_errno("close");
5159 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
5160 		err = got_error_from_errno("close");
5161 	if (blob1)
5162 		got_object_blob_close(blob1);
5163 	if (fd != -1 && close(fd) == -1 && err == NULL)
5164 		err = got_error_from_errno("close");
5165 	if (ondisk_file && fclose(ondisk_file) == EOF && err == NULL)
5166 		err = got_error_from_errno("fclose");
5167 	return err;
5168 }
5169 
5170 static const struct got_error *
5171 collect_commitables(void *arg, unsigned char status,
5172     unsigned char staged_status, const char *relpath,
5173     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5174     struct got_object_id *commit_id, int dirfd, const char *de_name)
5175 {
5176 	struct collect_commitables_arg *a = arg;
5177 	const struct got_error *err = NULL;
5178 	struct got_commitable *ct = NULL;
5179 	struct got_pathlist_entry *new = NULL;
5180 	char *parent_path = NULL, *path = NULL;
5181 	struct stat sb;
5182 
5183 	if (a->have_staged_files) {
5184 		if (staged_status != GOT_STATUS_MODIFY &&
5185 		    staged_status != GOT_STATUS_ADD &&
5186 		    staged_status != GOT_STATUS_DELETE)
5187 			return NULL;
5188 	} else {
5189 		if (status == GOT_STATUS_CONFLICT)
5190 			return got_error(GOT_ERR_COMMIT_CONFLICT);
5191 
5192 		if (status != GOT_STATUS_MODIFY &&
5193 		    status != GOT_STATUS_MODE_CHANGE &&
5194 		    status != GOT_STATUS_ADD &&
5195 		    status != GOT_STATUS_DELETE)
5196 			return NULL;
5197 	}
5198 
5199 	if (asprintf(&path, "/%s", relpath) == -1) {
5200 		err = got_error_from_errno("asprintf");
5201 		goto done;
5202 	}
5203 	if (strcmp(path, "/") == 0) {
5204 		parent_path = strdup("");
5205 		if (parent_path == NULL)
5206 			return got_error_from_errno("strdup");
5207 	} else {
5208 		err = got_path_dirname(&parent_path, path);
5209 		if (err)
5210 			return err;
5211 	}
5212 
5213 	ct = calloc(1, sizeof(*ct));
5214 	if (ct == NULL) {
5215 		err = got_error_from_errno("calloc");
5216 		goto done;
5217 	}
5218 
5219 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
5220 	    relpath) == -1) {
5221 		err = got_error_from_errno("asprintf");
5222 		goto done;
5223 	}
5224 
5225 	if (staged_status == GOT_STATUS_ADD ||
5226 	    staged_status == GOT_STATUS_MODIFY) {
5227 		struct got_fileindex_entry *ie;
5228 		ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
5229 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
5230 		case GOT_FILEIDX_MODE_REGULAR_FILE:
5231 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
5232 			ct->mode = S_IFREG;
5233 			break;
5234 		case GOT_FILEIDX_MODE_SYMLINK:
5235 			ct->mode = S_IFLNK;
5236 			break;
5237 		default:
5238 			err = got_error_path(path, GOT_ERR_BAD_FILETYPE);
5239 			goto done;
5240 		}
5241 		ct->mode |= got_fileindex_entry_perms_get(ie);
5242 	} else if (status != GOT_STATUS_DELETE &&
5243 	    staged_status != GOT_STATUS_DELETE) {
5244 		if (dirfd != -1) {
5245 			if (fstatat(dirfd, de_name, &sb,
5246 			    AT_SYMLINK_NOFOLLOW) == -1) {
5247 				err = got_error_from_errno2("fstatat",
5248 				    ct->ondisk_path);
5249 				goto done;
5250 			}
5251 		} else if (lstat(ct->ondisk_path, &sb) == -1) {
5252 			err = got_error_from_errno2("lstat", ct->ondisk_path);
5253 			goto done;
5254 		}
5255 		ct->mode = sb.st_mode;
5256 	}
5257 
5258 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
5259 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
5260 	    relpath) == -1) {
5261 		err = got_error_from_errno("asprintf");
5262 		goto done;
5263 	}
5264 
5265 	if (S_ISLNK(ct->mode) && staged_status == GOT_STATUS_NO_CHANGE &&
5266 	    status == GOT_STATUS_ADD && !a->allow_bad_symlinks) {
5267 		int is_bad_symlink;
5268 		char target_path[PATH_MAX];
5269 		ssize_t target_len;
5270 		target_len = readlink(ct->ondisk_path, target_path,
5271 		    sizeof(target_path));
5272 		if (target_len == -1) {
5273 			err = got_error_from_errno2("readlink",
5274 			    ct->ondisk_path);
5275 			goto done;
5276 		}
5277 		err = is_bad_symlink_target(&is_bad_symlink, target_path,
5278 		    target_len, ct->ondisk_path, a->worktree->root_path);
5279 		if (err)
5280 			goto done;
5281 		if (is_bad_symlink) {
5282 			err = got_error_path(ct->ondisk_path,
5283 			    GOT_ERR_BAD_SYMLINK);
5284 			goto done;
5285 		}
5286 	}
5287 
5288 
5289 	ct->status = status;
5290 	ct->staged_status = staged_status;
5291 	ct->blob_id = NULL; /* will be filled in when blob gets created */
5292 	if (ct->status != GOT_STATUS_ADD &&
5293 	    ct->staged_status != GOT_STATUS_ADD) {
5294 		ct->base_blob_id = got_object_id_dup(blob_id);
5295 		if (ct->base_blob_id == NULL) {
5296 			err = got_error_from_errno("got_object_id_dup");
5297 			goto done;
5298 		}
5299 		ct->base_commit_id = got_object_id_dup(commit_id);
5300 		if (ct->base_commit_id == NULL) {
5301 			err = got_error_from_errno("got_object_id_dup");
5302 			goto done;
5303 		}
5304 	}
5305 	if (ct->staged_status == GOT_STATUS_ADD ||
5306 	    ct->staged_status == GOT_STATUS_MODIFY) {
5307 		ct->staged_blob_id = got_object_id_dup(staged_blob_id);
5308 		if (ct->staged_blob_id == NULL) {
5309 			err = got_error_from_errno("got_object_id_dup");
5310 			goto done;
5311 		}
5312 	}
5313 	ct->path = strdup(path);
5314 	if (ct->path == NULL) {
5315 		err = got_error_from_errno("strdup");
5316 		goto done;
5317 	}
5318 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
5319 	if (err)
5320 		goto done;
5321 
5322 	if (a->diff_outfile && ct && new != NULL) {
5323 		err = append_ct_diff(ct, &a->diff_header_shown,
5324 		    a->diff_outfile, a->f1, a->f2, dirfd, de_name,
5325 		    a->have_staged_files, a->repo, a->worktree);
5326 		if (err)
5327 			goto done;
5328 	}
5329 done:
5330 	if (ct && (err || new == NULL))
5331 		free_commitable(ct);
5332 	free(parent_path);
5333 	free(path);
5334 	return err;
5335 }
5336 
5337 static const struct got_error *write_tree(struct got_object_id **, int *,
5338     struct got_tree_object *, const char *, struct got_pathlist_head *,
5339     got_worktree_status_cb status_cb, void *status_arg,
5340     struct got_repository *);
5341 
5342 static const struct got_error *
5343 write_subtree(struct got_object_id **new_subtree_id, int *nentries,
5344     struct got_tree_entry *te, const char *parent_path,
5345     struct got_pathlist_head *commitable_paths,
5346     got_worktree_status_cb status_cb, void *status_arg,
5347     struct got_repository *repo)
5348 {
5349 	const struct got_error *err = NULL;
5350 	struct got_tree_object *subtree;
5351 	char *subpath;
5352 
5353 	if (asprintf(&subpath, "%s%s%s", parent_path,
5354 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
5355 		return got_error_from_errno("asprintf");
5356 
5357 	err = got_object_open_as_tree(&subtree, repo, &te->id);
5358 	if (err)
5359 		return err;
5360 
5361 	err = write_tree(new_subtree_id, nentries, subtree, subpath,
5362 	    commitable_paths, status_cb, status_arg, repo);
5363 	got_object_tree_close(subtree);
5364 	free(subpath);
5365 	return err;
5366 }
5367 
5368 static const struct got_error *
5369 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
5370 {
5371 	const struct got_error *err = NULL;
5372 	char *ct_parent_path = NULL;
5373 
5374 	*match = 0;
5375 
5376 	if (strchr(ct->in_repo_path, '/') == NULL) {
5377 		*match = got_path_is_root_dir(path);
5378 		return NULL;
5379 	}
5380 
5381 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
5382 	if (err)
5383 		return err;
5384 	*match = (strcmp(path, ct_parent_path) == 0);
5385 	free(ct_parent_path);
5386 	return err;
5387 }
5388 
5389 static mode_t
5390 get_ct_file_mode(struct got_commitable *ct)
5391 {
5392 	if (S_ISLNK(ct->mode))
5393 		return S_IFLNK;
5394 
5395 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
5396 }
5397 
5398 static const struct got_error *
5399 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
5400     struct got_tree_entry *te, struct got_commitable *ct)
5401 {
5402 	const struct got_error *err = NULL;
5403 
5404 	*new_te = NULL;
5405 
5406 	err = got_object_tree_entry_dup(new_te, te);
5407 	if (err)
5408 		goto done;
5409 
5410 	(*new_te)->mode = get_ct_file_mode(ct);
5411 
5412 	if (ct->staged_status == GOT_STATUS_MODIFY)
5413 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5414 		    sizeof((*new_te)->id));
5415 	else
5416 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5417 done:
5418 	if (err && *new_te) {
5419 		free(*new_te);
5420 		*new_te = NULL;
5421 	}
5422 	return err;
5423 }
5424 
5425 static const struct got_error *
5426 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
5427     struct got_commitable *ct)
5428 {
5429 	const struct got_error *err = NULL;
5430 	char *ct_name = NULL;
5431 
5432 	 *new_te = NULL;
5433 
5434 	*new_te = calloc(1, sizeof(**new_te));
5435 	if (*new_te == NULL)
5436 		return got_error_from_errno("calloc");
5437 
5438 	err = got_path_basename(&ct_name, ct->path);
5439 	if (err)
5440 		goto done;
5441 	if (strlcpy((*new_te)->name, ct_name, sizeof((*new_te)->name)) >=
5442 	    sizeof((*new_te)->name)) {
5443 		err = got_error(GOT_ERR_NO_SPACE);
5444 		goto done;
5445 	}
5446 
5447 	(*new_te)->mode = get_ct_file_mode(ct);
5448 
5449 	if (ct->staged_status == GOT_STATUS_ADD)
5450 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5451 		    sizeof((*new_te)->id));
5452 	else
5453 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5454 done:
5455 	free(ct_name);
5456 	if (err && *new_te) {
5457 		free(*new_te);
5458 		*new_te = NULL;
5459 	}
5460 	return err;
5461 }
5462 
5463 static const struct got_error *
5464 insert_tree_entry(struct got_tree_entry *new_te,
5465     struct got_pathlist_head *paths)
5466 {
5467 	const struct got_error *err = NULL;
5468 	struct got_pathlist_entry *new_pe;
5469 
5470 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
5471 	if (err)
5472 		return err;
5473 	if (new_pe == NULL)
5474 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
5475 	return NULL;
5476 }
5477 
5478 static const struct got_error *
5479 report_ct_status(struct got_commitable *ct,
5480     got_worktree_status_cb status_cb, void *status_arg)
5481 {
5482 	const char *ct_path = ct->path;
5483 	unsigned char status;
5484 
5485 	if (status_cb == NULL) /* no commit progress output desired */
5486 		return NULL;
5487 
5488 	while (ct_path[0] == '/')
5489 		ct_path++;
5490 
5491 	if (ct->staged_status != GOT_STATUS_NO_CHANGE)
5492 		status = ct->staged_status;
5493 	else
5494 		status = ct->status;
5495 
5496 	return (*status_cb)(status_arg, status, GOT_STATUS_NO_CHANGE,
5497 	    ct_path, ct->blob_id, NULL, NULL, -1, NULL);
5498 }
5499 
5500 static const struct got_error *
5501 match_modified_subtree(int *modified, struct got_tree_entry *te,
5502     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
5503 {
5504 	const struct got_error *err = NULL;
5505 	struct got_pathlist_entry *pe;
5506 	char *te_path;
5507 
5508 	*modified = 0;
5509 
5510 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
5511 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
5512 	    te->name) == -1)
5513 		return got_error_from_errno("asprintf");
5514 
5515 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5516 		struct got_commitable *ct = pe->data;
5517 		*modified = got_path_is_child(ct->in_repo_path, te_path,
5518 		    strlen(te_path));
5519 		if (*modified)
5520 			break;
5521 	}
5522 
5523 	free(te_path);
5524 	return err;
5525 }
5526 
5527 static const struct got_error *
5528 match_deleted_or_modified_ct(struct got_commitable **ctp,
5529     struct got_tree_entry *te, const char *base_tree_path,
5530     struct got_pathlist_head *commitable_paths)
5531 {
5532 	const struct got_error *err = NULL;
5533 	struct got_pathlist_entry *pe;
5534 
5535 	*ctp = NULL;
5536 
5537 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5538 		struct got_commitable *ct = pe->data;
5539 		char *ct_name = NULL;
5540 		int path_matches;
5541 
5542 		if (ct->staged_status == GOT_STATUS_NO_CHANGE) {
5543 			if (ct->status != GOT_STATUS_MODIFY &&
5544 			    ct->status != GOT_STATUS_MODE_CHANGE &&
5545 			    ct->status != GOT_STATUS_DELETE)
5546 				continue;
5547 		} else {
5548 			if (ct->staged_status != GOT_STATUS_MODIFY &&
5549 			    ct->staged_status != GOT_STATUS_DELETE)
5550 				continue;
5551 		}
5552 
5553 		if (got_object_id_cmp(ct->base_blob_id, &te->id) != 0)
5554 			continue;
5555 
5556 		err = match_ct_parent_path(&path_matches, ct, base_tree_path);
5557 		if (err)
5558 			return err;
5559 		if (!path_matches)
5560 			continue;
5561 
5562 		err = got_path_basename(&ct_name, pe->path);
5563 		if (err)
5564 			return err;
5565 
5566 		if (strcmp(te->name, ct_name) != 0) {
5567 			free(ct_name);
5568 			continue;
5569 		}
5570 		free(ct_name);
5571 
5572 		*ctp = ct;
5573 		break;
5574 	}
5575 
5576 	return err;
5577 }
5578 
5579 static const struct got_error *
5580 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
5581     const char *child_path, const char *path_base_tree,
5582     struct got_pathlist_head *commitable_paths,
5583     got_worktree_status_cb status_cb, void *status_arg,
5584     struct got_repository *repo)
5585 {
5586 	const struct got_error *err = NULL;
5587 	struct got_tree_entry *new_te;
5588 	char *subtree_path;
5589 	struct got_object_id *id = NULL;
5590 	int nentries;
5591 
5592 	*new_tep = NULL;
5593 
5594 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
5595 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
5596 	    child_path) == -1)
5597 		return got_error_from_errno("asprintf");
5598 
5599 	new_te = calloc(1, sizeof(*new_te));
5600 	if (new_te == NULL)
5601 		return got_error_from_errno("calloc");
5602 	new_te->mode = S_IFDIR;
5603 
5604 	if (strlcpy(new_te->name, child_path, sizeof(new_te->name)) >=
5605 	    sizeof(new_te->name)) {
5606 		err = got_error(GOT_ERR_NO_SPACE);
5607 		goto done;
5608 	}
5609 	err = write_tree(&id, &nentries, NULL, subtree_path,
5610 	    commitable_paths, status_cb, status_arg, repo);
5611 	if (err) {
5612 		free(new_te);
5613 		goto done;
5614 	}
5615 	memcpy(&new_te->id, id, sizeof(new_te->id));
5616 done:
5617 	free(id);
5618 	free(subtree_path);
5619 	if (err == NULL)
5620 		*new_tep = new_te;
5621 	return err;
5622 }
5623 
5624 static const struct got_error *
5625 write_tree(struct got_object_id **new_tree_id, int *nentries,
5626     struct got_tree_object *base_tree, const char *path_base_tree,
5627     struct got_pathlist_head *commitable_paths,
5628     got_worktree_status_cb status_cb, void *status_arg,
5629     struct got_repository *repo)
5630 {
5631 	const struct got_error *err = NULL;
5632 	struct got_pathlist_head paths;
5633 	struct got_tree_entry *te, *new_te = NULL;
5634 	struct got_pathlist_entry *pe;
5635 
5636 	TAILQ_INIT(&paths);
5637 	*nentries = 0;
5638 
5639 	/* Insert, and recurse into, newly added entries first. */
5640 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5641 		struct got_commitable *ct = pe->data;
5642 		char *child_path = NULL, *slash;
5643 
5644 		if ((ct->status != GOT_STATUS_ADD &&
5645 		    ct->staged_status != GOT_STATUS_ADD) ||
5646 		    (ct->flags & GOT_COMMITABLE_ADDED))
5647 			continue;
5648 
5649 		if (!got_path_is_child(ct->in_repo_path, path_base_tree,
5650 		    strlen(path_base_tree)))
5651 			continue;
5652 
5653 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
5654 		    ct->in_repo_path);
5655 		if (err)
5656 			goto done;
5657 
5658 		slash = strchr(child_path, '/');
5659 		if (slash == NULL) {
5660 			err = alloc_added_blob_tree_entry(&new_te, ct);
5661 			if (err)
5662 				goto done;
5663 			err = report_ct_status(ct, status_cb, status_arg);
5664 			if (err)
5665 				goto done;
5666 			ct->flags |= GOT_COMMITABLE_ADDED;
5667 			err = insert_tree_entry(new_te, &paths);
5668 			if (err)
5669 				goto done;
5670 			(*nentries)++;
5671 		} else {
5672 			*slash = '\0'; /* trim trailing path components */
5673 			if (base_tree == NULL ||
5674 			    got_object_tree_find_entry(base_tree, child_path)
5675 			    == NULL) {
5676 				err = make_subtree_for_added_blob(&new_te,
5677 				    child_path, path_base_tree,
5678 				    commitable_paths, status_cb, status_arg,
5679 				    repo);
5680 				if (err)
5681 					goto done;
5682 				err = insert_tree_entry(new_te, &paths);
5683 				if (err)
5684 					goto done;
5685 				(*nentries)++;
5686 			}
5687 		}
5688 	}
5689 
5690 	if (base_tree) {
5691 		int i, nbase_entries;
5692 		/* Handle modified and deleted entries. */
5693 		nbase_entries = got_object_tree_get_nentries(base_tree);
5694 		for (i = 0; i < nbase_entries; i++) {
5695 			struct got_commitable *ct = NULL;
5696 
5697 			te = got_object_tree_get_entry(base_tree, i);
5698 			if (got_object_tree_entry_is_submodule(te)) {
5699 				/* Entry is a submodule; just copy it. */
5700 				err = got_object_tree_entry_dup(&new_te, te);
5701 				if (err)
5702 					goto done;
5703 				err = insert_tree_entry(new_te, &paths);
5704 				if (err)
5705 					goto done;
5706 				(*nentries)++;
5707 				continue;
5708 			}
5709 
5710 			if (S_ISDIR(te->mode)) {
5711 				int modified;
5712 				err = got_object_tree_entry_dup(&new_te, te);
5713 				if (err)
5714 					goto done;
5715 				err = match_modified_subtree(&modified, te,
5716 				    path_base_tree, commitable_paths);
5717 				if (err)
5718 					goto done;
5719 				/* Avoid recursion into unmodified subtrees. */
5720 				if (modified) {
5721 					struct got_object_id *new_id;
5722 					int nsubentries;
5723 					err = write_subtree(&new_id,
5724 					    &nsubentries, te,
5725 					    path_base_tree, commitable_paths,
5726 					    status_cb, status_arg, repo);
5727 					if (err)
5728 						goto done;
5729 					if (nsubentries == 0) {
5730 						/* All entries were deleted. */
5731 						free(new_id);
5732 						continue;
5733 					}
5734 					memcpy(&new_te->id, new_id,
5735 					    sizeof(new_te->id));
5736 					free(new_id);
5737 				}
5738 				err = insert_tree_entry(new_te, &paths);
5739 				if (err)
5740 					goto done;
5741 				(*nentries)++;
5742 				continue;
5743 			}
5744 
5745 			err = match_deleted_or_modified_ct(&ct, te,
5746 			    path_base_tree, commitable_paths);
5747 			if (err)
5748 				goto done;
5749 			if (ct) {
5750 				/* NB: Deleted entries get dropped here. */
5751 				if (ct->status == GOT_STATUS_MODIFY ||
5752 				    ct->status == GOT_STATUS_MODE_CHANGE ||
5753 				    ct->staged_status == GOT_STATUS_MODIFY) {
5754 					err = alloc_modified_blob_tree_entry(
5755 					    &new_te, te, ct);
5756 					if (err)
5757 						goto done;
5758 					err = insert_tree_entry(new_te, &paths);
5759 					if (err)
5760 						goto done;
5761 					(*nentries)++;
5762 				}
5763 				err = report_ct_status(ct, status_cb,
5764 				    status_arg);
5765 				if (err)
5766 					goto done;
5767 			} else {
5768 				/* Entry is unchanged; just copy it. */
5769 				err = got_object_tree_entry_dup(&new_te, te);
5770 				if (err)
5771 					goto done;
5772 				err = insert_tree_entry(new_te, &paths);
5773 				if (err)
5774 					goto done;
5775 				(*nentries)++;
5776 			}
5777 		}
5778 	}
5779 
5780 	/* Write new list of entries; deleted entries have been dropped. */
5781 	err = got_object_tree_create(new_tree_id, &paths, *nentries, repo);
5782 done:
5783 	got_pathlist_free(&paths);
5784 	return err;
5785 }
5786 
5787 static const struct got_error *
5788 update_fileindex_after_commit(struct got_worktree *worktree,
5789     struct got_pathlist_head *commitable_paths,
5790     struct got_object_id *new_base_commit_id,
5791     struct got_fileindex *fileindex, int have_staged_files)
5792 {
5793 	const struct got_error *err = NULL;
5794 	struct got_pathlist_entry *pe;
5795 	char *relpath = NULL;
5796 
5797 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5798 		struct got_fileindex_entry *ie;
5799 		struct got_commitable *ct = pe->data;
5800 
5801 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
5802 
5803 		err = got_path_skip_common_ancestor(&relpath,
5804 		    worktree->root_path, ct->ondisk_path);
5805 		if (err)
5806 			goto done;
5807 
5808 		if (ie) {
5809 			if (ct->status == GOT_STATUS_DELETE ||
5810 			    ct->staged_status == GOT_STATUS_DELETE) {
5811 				got_fileindex_entry_remove(fileindex, ie);
5812 			} else if (ct->staged_status == GOT_STATUS_ADD ||
5813 			    ct->staged_status == GOT_STATUS_MODIFY) {
5814 				got_fileindex_entry_stage_set(ie,
5815 				    GOT_FILEIDX_STAGE_NONE);
5816 				got_fileindex_entry_staged_filetype_set(ie, 0);
5817 
5818 				err = got_fileindex_entry_update(ie,
5819 				    worktree->root_fd, relpath,
5820 				    ct->staged_blob_id->sha1,
5821 				    new_base_commit_id->sha1,
5822 				    !have_staged_files);
5823 			} else
5824 				err = got_fileindex_entry_update(ie,
5825 				    worktree->root_fd, relpath,
5826 				    ct->blob_id->sha1,
5827 				    new_base_commit_id->sha1,
5828 				    !have_staged_files);
5829 		} else {
5830 			err = got_fileindex_entry_alloc(&ie, pe->path);
5831 			if (err)
5832 				goto done;
5833 			err = got_fileindex_entry_update(ie,
5834 			    worktree->root_fd, relpath, ct->blob_id->sha1,
5835 			    new_base_commit_id->sha1, 1);
5836 			if (err) {
5837 				got_fileindex_entry_free(ie);
5838 				goto done;
5839 			}
5840 			err = got_fileindex_entry_add(fileindex, ie);
5841 			if (err) {
5842 				got_fileindex_entry_free(ie);
5843 				goto done;
5844 			}
5845 		}
5846 		free(relpath);
5847 		relpath = NULL;
5848 	}
5849 done:
5850 	free(relpath);
5851 	return err;
5852 }
5853 
5854 
5855 static const struct got_error *
5856 check_out_of_date(const char *in_repo_path, unsigned char status,
5857     unsigned char staged_status, struct got_object_id *base_blob_id,
5858     struct got_object_id *base_commit_id,
5859     struct got_object_id *head_commit_id, struct got_repository *repo,
5860     int ood_errcode)
5861 {
5862 	const struct got_error *err = NULL;
5863 	struct got_commit_object *commit = NULL;
5864 	struct got_object_id *id = NULL;
5865 
5866 	if (status != GOT_STATUS_ADD && staged_status != GOT_STATUS_ADD) {
5867 		/* Trivial case: base commit == head commit */
5868 		if (got_object_id_cmp(base_commit_id, head_commit_id) == 0)
5869 			return NULL;
5870 		/*
5871 		 * Ensure file content which local changes were based
5872 		 * on matches file content in the branch head.
5873 		 */
5874 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
5875 		if (err)
5876 			goto done;
5877 		err = got_object_id_by_path(&id, repo, commit, in_repo_path);
5878 		if (err) {
5879 			if (err->code == GOT_ERR_NO_TREE_ENTRY)
5880 				err = got_error(ood_errcode);
5881 			goto done;
5882 		} else if (got_object_id_cmp(id, base_blob_id) != 0)
5883 			err = got_error(ood_errcode);
5884 	} else {
5885 		/* Require that added files don't exist in the branch head. */
5886 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
5887 		if (err)
5888 			goto done;
5889 		err = got_object_id_by_path(&id, repo, commit, in_repo_path);
5890 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
5891 			goto done;
5892 		err = id ? got_error(ood_errcode) : NULL;
5893 	}
5894 done:
5895 	free(id);
5896 	if (commit)
5897 		got_object_commit_close(commit);
5898 	return err;
5899 }
5900 
5901 static const struct got_error *
5902 commit_worktree(struct got_object_id **new_commit_id,
5903     struct got_pathlist_head *commitable_paths,
5904     struct got_object_id *head_commit_id,
5905     struct got_object_id *parent_id2,
5906     struct got_worktree *worktree,
5907     const char *author, const char *committer, char *diff_path,
5908     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
5909     got_worktree_status_cb status_cb, void *status_arg,
5910     struct got_repository *repo)
5911 {
5912 	const struct got_error *err = NULL, *unlockerr = NULL;
5913 	struct got_pathlist_entry *pe;
5914 	const char *head_ref_name = NULL;
5915 	struct got_commit_object *head_commit = NULL;
5916 	struct got_reference *head_ref2 = NULL;
5917 	struct got_object_id *head_commit_id2 = NULL;
5918 	struct got_tree_object *head_tree = NULL;
5919 	struct got_object_id *new_tree_id = NULL;
5920 	int nentries, nparents = 0;
5921 	struct got_object_id_queue parent_ids;
5922 	struct got_object_qid *pid = NULL;
5923 	char *logmsg = NULL;
5924 	time_t timestamp;
5925 
5926 	*new_commit_id = NULL;
5927 
5928 	STAILQ_INIT(&parent_ids);
5929 
5930 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
5931 	if (err)
5932 		goto done;
5933 
5934 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
5935 	if (err)
5936 		goto done;
5937 
5938 	if (commit_msg_cb != NULL) {
5939 		err = commit_msg_cb(commitable_paths, diff_path,
5940 		    &logmsg, commit_arg);
5941 		if (err)
5942 			goto done;
5943 	}
5944 
5945 	if (logmsg == NULL || strlen(logmsg) == 0) {
5946 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
5947 		goto done;
5948 	}
5949 
5950 	/* Create blobs from added and modified files and record their IDs. */
5951 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5952 		struct got_commitable *ct = pe->data;
5953 		char *ondisk_path;
5954 
5955 		/* Blobs for staged files already exist. */
5956 		if (ct->staged_status == GOT_STATUS_ADD ||
5957 		    ct->staged_status == GOT_STATUS_MODIFY)
5958 			continue;
5959 
5960 		if (ct->status != GOT_STATUS_ADD &&
5961 		    ct->status != GOT_STATUS_MODIFY &&
5962 		    ct->status != GOT_STATUS_MODE_CHANGE)
5963 			continue;
5964 
5965 		if (asprintf(&ondisk_path, "%s/%s",
5966 		    worktree->root_path, pe->path) == -1) {
5967 			err = got_error_from_errno("asprintf");
5968 			goto done;
5969 		}
5970 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
5971 		free(ondisk_path);
5972 		if (err)
5973 			goto done;
5974 	}
5975 
5976 	/* Recursively write new tree objects. */
5977 	err = write_tree(&new_tree_id, &nentries, head_tree, "/",
5978 	    commitable_paths, status_cb, status_arg, repo);
5979 	if (err)
5980 		goto done;
5981 
5982 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
5983 	if (err)
5984 		goto done;
5985 	STAILQ_INSERT_TAIL(&parent_ids, pid, entry);
5986 	nparents++;
5987 	if (parent_id2) {
5988 		err = got_object_qid_alloc(&pid, parent_id2);
5989 		if (err)
5990 			goto done;
5991 		STAILQ_INSERT_TAIL(&parent_ids, pid, entry);
5992 		nparents++;
5993 	}
5994 	timestamp = time(NULL);
5995 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
5996 	    nparents, author, timestamp, committer, timestamp, logmsg, repo);
5997 	if (logmsg != NULL)
5998 		free(logmsg);
5999 	if (err)
6000 		goto done;
6001 
6002 	/* Check if a concurrent commit to our branch has occurred. */
6003 	head_ref_name = got_worktree_get_head_ref_name(worktree);
6004 	if (head_ref_name == NULL) {
6005 		err = got_error_from_errno("got_worktree_get_head_ref_name");
6006 		goto done;
6007 	}
6008 	/* Lock the reference here to prevent concurrent modification. */
6009 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
6010 	if (err)
6011 		goto done;
6012 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
6013 	if (err)
6014 		goto done;
6015 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
6016 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
6017 		goto done;
6018 	}
6019 	/* Update branch head in repository. */
6020 	err = got_ref_change_ref(head_ref2, *new_commit_id);
6021 	if (err)
6022 		goto done;
6023 	err = got_ref_write(head_ref2, repo);
6024 	if (err)
6025 		goto done;
6026 
6027 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
6028 	if (err)
6029 		goto done;
6030 
6031 	err = ref_base_commit(worktree, repo);
6032 	if (err)
6033 		goto done;
6034 done:
6035 	got_object_id_queue_free(&parent_ids);
6036 	if (head_tree)
6037 		got_object_tree_close(head_tree);
6038 	if (head_commit)
6039 		got_object_commit_close(head_commit);
6040 	free(head_commit_id2);
6041 	if (head_ref2) {
6042 		unlockerr = got_ref_unlock(head_ref2);
6043 		if (unlockerr && err == NULL)
6044 			err = unlockerr;
6045 		got_ref_close(head_ref2);
6046 	}
6047 	return err;
6048 }
6049 
6050 static const struct got_error *
6051 check_path_is_commitable(const char *path,
6052     struct got_pathlist_head *commitable_paths)
6053 {
6054 	struct got_pathlist_entry *cpe = NULL;
6055 	size_t path_len = strlen(path);
6056 
6057 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
6058 		struct got_commitable *ct = cpe->data;
6059 		const char *ct_path = ct->path;
6060 
6061 		while (ct_path[0] == '/')
6062 			ct_path++;
6063 
6064 		if (strcmp(path, ct_path) == 0 ||
6065 		    got_path_is_child(ct_path, path, path_len))
6066 			break;
6067 	}
6068 
6069 	if (cpe == NULL)
6070 		return got_error_path(path, GOT_ERR_BAD_PATH);
6071 
6072 	return NULL;
6073 }
6074 
6075 static const struct got_error *
6076 check_staged_file(void *arg, struct got_fileindex_entry *ie)
6077 {
6078 	int *have_staged_files = arg;
6079 
6080 	if (got_fileindex_entry_stage_get(ie) != GOT_FILEIDX_STAGE_NONE) {
6081 		*have_staged_files = 1;
6082 		return got_error(GOT_ERR_CANCELLED);
6083 	}
6084 
6085 	return NULL;
6086 }
6087 
6088 static const struct got_error *
6089 check_non_staged_files(struct got_fileindex *fileindex,
6090     struct got_pathlist_head *paths)
6091 {
6092 	struct got_pathlist_entry *pe;
6093 	struct got_fileindex_entry *ie;
6094 
6095 	TAILQ_FOREACH(pe, paths, entry) {
6096 		if (pe->path[0] == '\0')
6097 			continue;
6098 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
6099 		if (ie == NULL)
6100 			return got_error_path(pe->path, GOT_ERR_BAD_PATH);
6101 		if (got_fileindex_entry_stage_get(ie) == GOT_FILEIDX_STAGE_NONE)
6102 			return got_error_path(pe->path,
6103 			    GOT_ERR_FILE_NOT_STAGED);
6104 	}
6105 
6106 	return NULL;
6107 }
6108 
6109 const struct got_error *
6110 got_worktree_commit(struct got_object_id **new_commit_id,
6111     struct got_worktree *worktree, struct got_pathlist_head *paths,
6112     const char *author, const char *committer, int allow_bad_symlinks,
6113     int show_diff, got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
6114     got_worktree_status_cb status_cb, void *status_arg,
6115     struct got_repository *repo)
6116 {
6117 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
6118 	struct got_fileindex *fileindex = NULL;
6119 	char *fileindex_path = NULL;
6120 	struct got_pathlist_head commitable_paths;
6121 	struct collect_commitables_arg cc_arg;
6122 	struct got_pathlist_entry *pe;
6123 	struct got_reference *head_ref = NULL;
6124 	struct got_object_id *head_commit_id = NULL;
6125 	char *diff_path = NULL;
6126 	int have_staged_files = 0;
6127 
6128 	*new_commit_id = NULL;
6129 
6130 	memset(&cc_arg, 0, sizeof(cc_arg));
6131 	TAILQ_INIT(&commitable_paths);
6132 
6133 	err = lock_worktree(worktree, LOCK_EX);
6134 	if (err)
6135 		goto done;
6136 
6137 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6138 	if (err)
6139 		goto done;
6140 
6141 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6142 	if (err)
6143 		goto done;
6144 
6145 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
6146 	if (err)
6147 		goto done;
6148 
6149 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
6150 	    &have_staged_files);
6151 	if (err && err->code != GOT_ERR_CANCELLED)
6152 		goto done;
6153 	if (have_staged_files) {
6154 		err = check_non_staged_files(fileindex, paths);
6155 		if (err)
6156 			goto done;
6157 	}
6158 
6159 	cc_arg.commitable_paths = &commitable_paths;
6160 	cc_arg.worktree = worktree;
6161 	cc_arg.fileindex = fileindex;
6162 	cc_arg.repo = repo;
6163 	cc_arg.have_staged_files = have_staged_files;
6164 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
6165 	cc_arg.diff_header_shown = 0;
6166 	if (show_diff) {
6167 		err = got_opentemp_named(&diff_path, &cc_arg.diff_outfile,
6168 		    GOT_TMPDIR_STR "/got", ".diff");
6169 		if (err)
6170 			goto done;
6171 		cc_arg.f1 = got_opentemp();
6172 		if (cc_arg.f1 == NULL) {
6173 			err = got_error_from_errno("got_opentemp");
6174 			goto done;
6175 		}
6176 		cc_arg.f2 = got_opentemp();
6177 		if (cc_arg.f2 == NULL) {
6178 			err = got_error_from_errno("got_opentemp");
6179 			goto done;
6180 		}
6181 	}
6182 
6183 	TAILQ_FOREACH(pe, paths, entry) {
6184 		err = worktree_status(worktree, pe->path, fileindex, repo,
6185 		    collect_commitables, &cc_arg, NULL, NULL, 0, 0);
6186 		if (err)
6187 			goto done;
6188 	}
6189 
6190 	if (show_diff) {
6191 		if (fflush(cc_arg.diff_outfile) == EOF) {
6192 			err = got_error_from_errno("fflush");
6193 			goto done;
6194 		}
6195 	}
6196 
6197 	if (TAILQ_EMPTY(&commitable_paths)) {
6198 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6199 		goto done;
6200 	}
6201 
6202 	TAILQ_FOREACH(pe, paths, entry) {
6203 		err = check_path_is_commitable(pe->path, &commitable_paths);
6204 		if (err)
6205 			goto done;
6206 	}
6207 
6208 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
6209 		struct got_commitable *ct = pe->data;
6210 		const char *ct_path = ct->in_repo_path;
6211 
6212 		while (ct_path[0] == '/')
6213 			ct_path++;
6214 		err = check_out_of_date(ct_path, ct->status,
6215 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
6216 		    head_commit_id, repo, GOT_ERR_COMMIT_OUT_OF_DATE);
6217 		if (err)
6218 			goto done;
6219 
6220 	}
6221 
6222 	err = commit_worktree(new_commit_id, &commitable_paths,
6223 	    head_commit_id, NULL, worktree, author, committer,
6224 	    (diff_path && cc_arg.diff_header_shown) ? diff_path : NULL,
6225 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
6226 	if (err)
6227 		goto done;
6228 
6229 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6230 	    *new_commit_id, fileindex, have_staged_files);
6231 	sync_err = sync_fileindex(fileindex, fileindex_path);
6232 	if (sync_err && err == NULL)
6233 		err = sync_err;
6234 done:
6235 	if (fileindex)
6236 		got_fileindex_free(fileindex);
6237 	free(fileindex_path);
6238 	unlockerr = lock_worktree(worktree, LOCK_SH);
6239 	if (unlockerr && err == NULL)
6240 		err = unlockerr;
6241 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
6242 		struct got_commitable *ct = pe->data;
6243 		free_commitable(ct);
6244 	}
6245 	got_pathlist_free(&commitable_paths);
6246 	if (diff_path && unlink(diff_path) == -1 && err == NULL)
6247 		err = got_error_from_errno2("unlink", diff_path);
6248 	free(diff_path);
6249 	if (cc_arg.diff_outfile && fclose(cc_arg.diff_outfile) == EOF &&
6250 	    err == NULL)
6251 		err = got_error_from_errno("fclose");
6252 	return err;
6253 }
6254 
6255 const char *
6256 got_commitable_get_path(struct got_commitable *ct)
6257 {
6258 	return ct->path;
6259 }
6260 
6261 unsigned int
6262 got_commitable_get_status(struct got_commitable *ct)
6263 {
6264 	return ct->status;
6265 }
6266 
6267 struct check_rebase_ok_arg {
6268 	struct got_worktree *worktree;
6269 	struct got_repository *repo;
6270 };
6271 
6272 static const struct got_error *
6273 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
6274 {
6275 	const struct got_error *err = NULL;
6276 	struct check_rebase_ok_arg *a = arg;
6277 	unsigned char status;
6278 	struct stat sb;
6279 	char *ondisk_path;
6280 
6281 	/* Reject rebase of a work tree with mixed base commits. */
6282 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
6283 	    SHA1_DIGEST_LENGTH))
6284 		return got_error(GOT_ERR_MIXED_COMMITS);
6285 
6286 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
6287 	    == -1)
6288 		return got_error_from_errno("asprintf");
6289 
6290 	/* Reject rebase of a work tree with modified or staged files. */
6291 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
6292 	free(ondisk_path);
6293 	if (err)
6294 		return err;
6295 
6296 	if (status != GOT_STATUS_NO_CHANGE)
6297 		return got_error(GOT_ERR_MODIFIED);
6298 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
6299 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
6300 
6301 	return NULL;
6302 }
6303 
6304 const struct got_error *
6305 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
6306     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
6307     struct got_worktree *worktree, struct got_reference *branch,
6308     struct got_repository *repo)
6309 {
6310 	const struct got_error *err = NULL;
6311 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
6312 	char *branch_ref_name = NULL;
6313 	char *fileindex_path = NULL;
6314 	struct check_rebase_ok_arg ok_arg;
6315 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
6316 	struct got_object_id *wt_branch_tip = NULL;
6317 
6318 	*new_base_branch_ref = NULL;
6319 	*tmp_branch = NULL;
6320 	*fileindex = NULL;
6321 
6322 	err = lock_worktree(worktree, LOCK_EX);
6323 	if (err)
6324 		return err;
6325 
6326 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6327 	if (err)
6328 		goto done;
6329 
6330 	ok_arg.worktree = worktree;
6331 	ok_arg.repo = repo;
6332 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
6333 	    &ok_arg);
6334 	if (err)
6335 		goto done;
6336 
6337 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6338 	if (err)
6339 		goto done;
6340 
6341 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6342 	if (err)
6343 		goto done;
6344 
6345 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6346 	if (err)
6347 		goto done;
6348 
6349 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
6350 	    0);
6351 	if (err)
6352 		goto done;
6353 
6354 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
6355 	if (err)
6356 		goto done;
6357 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
6358 		err = got_error(GOT_ERR_REBASE_OUT_OF_DATE);
6359 		goto done;
6360 	}
6361 
6362 	err = got_ref_alloc_symref(new_base_branch_ref,
6363 	    new_base_branch_ref_name, wt_branch);
6364 	if (err)
6365 		goto done;
6366 	err = got_ref_write(*new_base_branch_ref, repo);
6367 	if (err)
6368 		goto done;
6369 
6370 	/* TODO Lock original branch's ref while rebasing? */
6371 
6372 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
6373 	if (err)
6374 		goto done;
6375 
6376 	err = got_ref_write(branch_ref, repo);
6377 	if (err)
6378 		goto done;
6379 
6380 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
6381 	    worktree->base_commit_id);
6382 	if (err)
6383 		goto done;
6384 	err = got_ref_write(*tmp_branch, repo);
6385 	if (err)
6386 		goto done;
6387 
6388 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
6389 	if (err)
6390 		goto done;
6391 done:
6392 	free(fileindex_path);
6393 	free(tmp_branch_name);
6394 	free(new_base_branch_ref_name);
6395 	free(branch_ref_name);
6396 	if (branch_ref)
6397 		got_ref_close(branch_ref);
6398 	if (wt_branch)
6399 		got_ref_close(wt_branch);
6400 	free(wt_branch_tip);
6401 	if (err) {
6402 		if (*new_base_branch_ref) {
6403 			got_ref_close(*new_base_branch_ref);
6404 			*new_base_branch_ref = NULL;
6405 		}
6406 		if (*tmp_branch) {
6407 			got_ref_close(*tmp_branch);
6408 			*tmp_branch = NULL;
6409 		}
6410 		if (*fileindex) {
6411 			got_fileindex_free(*fileindex);
6412 			*fileindex = NULL;
6413 		}
6414 		lock_worktree(worktree, LOCK_SH);
6415 	}
6416 	return err;
6417 }
6418 
6419 const struct got_error *
6420 got_worktree_rebase_continue(struct got_object_id **commit_id,
6421     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
6422     struct got_reference **branch, struct got_fileindex **fileindex,
6423     struct got_worktree *worktree, struct got_repository *repo)
6424 {
6425 	const struct got_error *err;
6426 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
6427 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
6428 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
6429 	char *fileindex_path = NULL;
6430 	int have_staged_files = 0;
6431 
6432 	*commit_id = NULL;
6433 	*new_base_branch = NULL;
6434 	*tmp_branch = NULL;
6435 	*branch = NULL;
6436 	*fileindex = NULL;
6437 
6438 	err = lock_worktree(worktree, LOCK_EX);
6439 	if (err)
6440 		return err;
6441 
6442 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6443 	if (err)
6444 		goto done;
6445 
6446 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
6447 	    &have_staged_files);
6448 	if (err && err->code != GOT_ERR_CANCELLED)
6449 		goto done;
6450 	if (have_staged_files) {
6451 		err = got_error(GOT_ERR_STAGED_PATHS);
6452 		goto done;
6453 	}
6454 
6455 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6456 	if (err)
6457 		goto done;
6458 
6459 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6460 	if (err)
6461 		goto done;
6462 
6463 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6464 	if (err)
6465 		goto done;
6466 
6467 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6468 	if (err)
6469 		goto done;
6470 
6471 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
6472 	if (err)
6473 		goto done;
6474 
6475 	err = got_ref_open(branch, repo,
6476 	    got_ref_get_symref_target(branch_ref), 0);
6477 	if (err)
6478 		goto done;
6479 
6480 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6481 	if (err)
6482 		goto done;
6483 
6484 	err = got_ref_resolve(commit_id, repo, commit_ref);
6485 	if (err)
6486 		goto done;
6487 
6488 	err = got_ref_open(new_base_branch, repo,
6489 	    new_base_branch_ref_name, 0);
6490 	if (err)
6491 		goto done;
6492 
6493 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
6494 	if (err)
6495 		goto done;
6496 done:
6497 	free(commit_ref_name);
6498 	free(branch_ref_name);
6499 	free(fileindex_path);
6500 	if (commit_ref)
6501 		got_ref_close(commit_ref);
6502 	if (branch_ref)
6503 		got_ref_close(branch_ref);
6504 	if (err) {
6505 		free(*commit_id);
6506 		*commit_id = NULL;
6507 		if (*tmp_branch) {
6508 			got_ref_close(*tmp_branch);
6509 			*tmp_branch = NULL;
6510 		}
6511 		if (*new_base_branch) {
6512 			got_ref_close(*new_base_branch);
6513 			*new_base_branch = NULL;
6514 		}
6515 		if (*branch) {
6516 			got_ref_close(*branch);
6517 			*branch = NULL;
6518 		}
6519 		if (*fileindex) {
6520 			got_fileindex_free(*fileindex);
6521 			*fileindex = NULL;
6522 		}
6523 		lock_worktree(worktree, LOCK_SH);
6524 	}
6525 	return err;
6526 }
6527 
6528 const struct got_error *
6529 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
6530 {
6531 	const struct got_error *err;
6532 	char *tmp_branch_name = NULL;
6533 
6534 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6535 	if (err)
6536 		return err;
6537 
6538 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
6539 	free(tmp_branch_name);
6540 	return NULL;
6541 }
6542 
6543 static const struct got_error *
6544 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
6545     const char *diff_path, char **logmsg, void *arg)
6546 {
6547 	*logmsg = arg;
6548 	return NULL;
6549 }
6550 
6551 static const struct got_error *
6552 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
6553     const char *path, struct got_object_id *blob_id,
6554     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
6555     int dirfd, const char *de_name)
6556 {
6557 	return NULL;
6558 }
6559 
6560 struct collect_merged_paths_arg {
6561 	got_worktree_checkout_cb progress_cb;
6562 	void *progress_arg;
6563 	struct got_pathlist_head *merged_paths;
6564 };
6565 
6566 static const struct got_error *
6567 collect_merged_paths(void *arg, unsigned char status, const char *path)
6568 {
6569 	const struct got_error *err;
6570 	struct collect_merged_paths_arg *a = arg;
6571 	char *p;
6572 	struct got_pathlist_entry *new;
6573 
6574 	err = (*a->progress_cb)(a->progress_arg, status, path);
6575 	if (err)
6576 		return err;
6577 
6578 	if (status != GOT_STATUS_MERGE &&
6579 	    status != GOT_STATUS_ADD &&
6580 	    status != GOT_STATUS_DELETE &&
6581 	    status != GOT_STATUS_CONFLICT)
6582 		return NULL;
6583 
6584 	p = strdup(path);
6585 	if (p == NULL)
6586 		return got_error_from_errno("strdup");
6587 
6588 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
6589 	if (err || new == NULL)
6590 		free(p);
6591 	return err;
6592 }
6593 
6594 void
6595 got_worktree_rebase_pathlist_free(struct got_pathlist_head *merged_paths)
6596 {
6597 	struct got_pathlist_entry *pe;
6598 
6599 	TAILQ_FOREACH(pe, merged_paths, entry)
6600 		free((char *)pe->path);
6601 
6602 	got_pathlist_free(merged_paths);
6603 }
6604 
6605 static const struct got_error *
6606 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
6607     int is_rebase, struct got_repository *repo)
6608 {
6609 	const struct got_error *err;
6610 	struct got_reference *commit_ref = NULL;
6611 
6612 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6613 	if (err) {
6614 		if (err->code != GOT_ERR_NOT_REF)
6615 			goto done;
6616 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
6617 		if (err)
6618 			goto done;
6619 		err = got_ref_write(commit_ref, repo);
6620 		if (err)
6621 			goto done;
6622 	} else if (is_rebase) {
6623 		struct got_object_id *stored_id;
6624 		int cmp;
6625 
6626 		err = got_ref_resolve(&stored_id, repo, commit_ref);
6627 		if (err)
6628 			goto done;
6629 		cmp = got_object_id_cmp(commit_id, stored_id);
6630 		free(stored_id);
6631 		if (cmp != 0) {
6632 			err = got_error(GOT_ERR_REBASE_COMMITID);
6633 			goto done;
6634 		}
6635 	}
6636 done:
6637 	if (commit_ref)
6638 		got_ref_close(commit_ref);
6639 	return err;
6640 }
6641 
6642 static const struct got_error *
6643 rebase_merge_files(struct got_pathlist_head *merged_paths,
6644     const char *commit_ref_name, struct got_worktree *worktree,
6645     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
6646     struct got_object_id *commit_id, struct got_repository *repo,
6647     got_worktree_checkout_cb progress_cb, void *progress_arg,
6648     got_cancel_cb cancel_cb, void *cancel_arg)
6649 {
6650 	const struct got_error *err;
6651 	struct got_reference *commit_ref = NULL;
6652 	struct collect_merged_paths_arg cmp_arg;
6653 	char *fileindex_path;
6654 
6655 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6656 
6657 	err = get_fileindex_path(&fileindex_path, worktree);
6658 	if (err)
6659 		return err;
6660 
6661 	cmp_arg.progress_cb = progress_cb;
6662 	cmp_arg.progress_arg = progress_arg;
6663 	cmp_arg.merged_paths = merged_paths;
6664 	err = merge_files(worktree, fileindex, fileindex_path,
6665 	    parent_commit_id, commit_id, repo, collect_merged_paths,
6666 	    &cmp_arg, cancel_cb, cancel_arg);
6667 	if (commit_ref)
6668 		got_ref_close(commit_ref);
6669 	return err;
6670 }
6671 
6672 const struct got_error *
6673 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
6674     struct got_worktree *worktree, struct got_fileindex *fileindex,
6675     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6676     struct got_repository *repo,
6677     got_worktree_checkout_cb progress_cb, void *progress_arg,
6678     got_cancel_cb cancel_cb, void *cancel_arg)
6679 {
6680 	const struct got_error *err;
6681 	char *commit_ref_name;
6682 
6683 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6684 	if (err)
6685 		return err;
6686 
6687 	err = store_commit_id(commit_ref_name, commit_id, 1, repo);
6688 	if (err)
6689 		goto done;
6690 
6691 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6692 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6693 	    progress_arg, cancel_cb, cancel_arg);
6694 done:
6695 	free(commit_ref_name);
6696 	return err;
6697 }
6698 
6699 const struct got_error *
6700 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
6701     struct got_worktree *worktree, struct got_fileindex *fileindex,
6702     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6703     struct got_repository *repo,
6704     got_worktree_checkout_cb progress_cb, void *progress_arg,
6705     got_cancel_cb cancel_cb, void *cancel_arg)
6706 {
6707 	const struct got_error *err;
6708 	char *commit_ref_name;
6709 
6710 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6711 	if (err)
6712 		return err;
6713 
6714 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
6715 	if (err)
6716 		goto done;
6717 
6718 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6719 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6720 	    progress_arg, cancel_cb, cancel_arg);
6721 done:
6722 	free(commit_ref_name);
6723 	return err;
6724 }
6725 
6726 static const struct got_error *
6727 rebase_commit(struct got_object_id **new_commit_id,
6728     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
6729     struct got_worktree *worktree, struct got_fileindex *fileindex,
6730     struct got_reference *tmp_branch, const char *committer,
6731     struct got_commit_object *orig_commit, const char *new_logmsg,
6732     struct got_repository *repo)
6733 {
6734 	const struct got_error *err, *sync_err;
6735 	struct got_pathlist_head commitable_paths;
6736 	struct collect_commitables_arg cc_arg;
6737 	char *fileindex_path = NULL;
6738 	struct got_reference *head_ref = NULL;
6739 	struct got_object_id *head_commit_id = NULL;
6740 	char *logmsg = NULL;
6741 
6742 	memset(&cc_arg, 0, sizeof(cc_arg));
6743 	TAILQ_INIT(&commitable_paths);
6744 	*new_commit_id = NULL;
6745 
6746 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6747 
6748 	err = get_fileindex_path(&fileindex_path, worktree);
6749 	if (err)
6750 		return err;
6751 
6752 	cc_arg.commitable_paths = &commitable_paths;
6753 	cc_arg.worktree = worktree;
6754 	cc_arg.repo = repo;
6755 	cc_arg.have_staged_files = 0;
6756 	/*
6757 	 * If possible get the status of individual files directly to
6758 	 * avoid crawling the entire work tree once per rebased commit.
6759 	 *
6760 	 * Ideally, merged_paths would contain a list of commitables
6761 	 * we could use so we could skip worktree_status() entirely.
6762 	 * However, we would then need carefully keep track of cumulative
6763 	 * effects of operations such as file additions and deletions
6764 	 * in 'got histedit -f' (folding multiple commits into one),
6765 	 * and this extra complexity is not really worth it.
6766 	 */
6767 	if (merged_paths) {
6768 		struct got_pathlist_entry *pe;
6769 		TAILQ_FOREACH(pe, merged_paths, entry) {
6770 			err = worktree_status(worktree, pe->path, fileindex,
6771 			    repo, collect_commitables, &cc_arg, NULL, NULL, 1,
6772 			    0);
6773 			if (err)
6774 				goto done;
6775 		}
6776 	} else {
6777 		err = worktree_status(worktree, "", fileindex, repo,
6778 		    collect_commitables, &cc_arg, NULL, NULL, 1, 0);
6779 		if (err)
6780 			goto done;
6781 	}
6782 
6783 	if (TAILQ_EMPTY(&commitable_paths)) {
6784 		/* No-op change; commit will be elided. */
6785 		err = got_ref_delete(commit_ref, repo);
6786 		if (err)
6787 			goto done;
6788 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6789 		goto done;
6790 	}
6791 
6792 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6793 	if (err)
6794 		goto done;
6795 
6796 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6797 	if (err)
6798 		goto done;
6799 
6800 	if (new_logmsg) {
6801 		logmsg = strdup(new_logmsg);
6802 		if (logmsg == NULL) {
6803 			err = got_error_from_errno("strdup");
6804 			goto done;
6805 		}
6806 	} else {
6807 		err = got_object_commit_get_logmsg(&logmsg, orig_commit);
6808 		if (err)
6809 			goto done;
6810 	}
6811 
6812 	/* NB: commit_worktree will call free(logmsg) */
6813 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
6814 	    NULL, worktree, got_object_commit_get_author(orig_commit),
6815 	    committer ? committer :
6816 	    got_object_commit_get_committer(orig_commit), NULL,
6817 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
6818 	if (err)
6819 		goto done;
6820 
6821 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
6822 	if (err)
6823 		goto done;
6824 
6825 	err = got_ref_delete(commit_ref, repo);
6826 	if (err)
6827 		goto done;
6828 
6829 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6830 	    *new_commit_id, fileindex, 0);
6831 	sync_err = sync_fileindex(fileindex, fileindex_path);
6832 	if (sync_err && err == NULL)
6833 		err = sync_err;
6834 done:
6835 	free(fileindex_path);
6836 	free(head_commit_id);
6837 	if (head_ref)
6838 		got_ref_close(head_ref);
6839 	if (err) {
6840 		free(*new_commit_id);
6841 		*new_commit_id = NULL;
6842 	}
6843 	return err;
6844 }
6845 
6846 const struct got_error *
6847 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
6848     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6849     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6850     const char *committer, struct got_commit_object *orig_commit,
6851     struct got_object_id *orig_commit_id, struct got_repository *repo)
6852 {
6853 	const struct got_error *err;
6854 	char *commit_ref_name;
6855 	struct got_reference *commit_ref = NULL;
6856 	struct got_object_id *commit_id = NULL;
6857 
6858 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6859 	if (err)
6860 		return err;
6861 
6862 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6863 	if (err)
6864 		goto done;
6865 	err = got_ref_resolve(&commit_id, repo, commit_ref);
6866 	if (err)
6867 		goto done;
6868 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
6869 		err = got_error(GOT_ERR_REBASE_COMMITID);
6870 		goto done;
6871 	}
6872 
6873 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6874 	    worktree, fileindex, tmp_branch, committer, orig_commit,
6875 	    NULL, repo);
6876 done:
6877 	if (commit_ref)
6878 		got_ref_close(commit_ref);
6879 	free(commit_ref_name);
6880 	free(commit_id);
6881 	return err;
6882 }
6883 
6884 const struct got_error *
6885 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
6886     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6887     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6888     const char *committer, struct got_commit_object *orig_commit,
6889     struct got_object_id *orig_commit_id, const char *new_logmsg,
6890     struct got_repository *repo)
6891 {
6892 	const struct got_error *err;
6893 	char *commit_ref_name;
6894 	struct got_reference *commit_ref = NULL;
6895 
6896 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6897 	if (err)
6898 		return err;
6899 
6900 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6901 	if (err)
6902 		goto done;
6903 
6904 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6905 	    worktree, fileindex, tmp_branch, committer, orig_commit,
6906 	    new_logmsg, repo);
6907 done:
6908 	if (commit_ref)
6909 		got_ref_close(commit_ref);
6910 	free(commit_ref_name);
6911 	return err;
6912 }
6913 
6914 const struct got_error *
6915 got_worktree_rebase_postpone(struct got_worktree *worktree,
6916     struct got_fileindex *fileindex)
6917 {
6918 	if (fileindex)
6919 		got_fileindex_free(fileindex);
6920 	return lock_worktree(worktree, LOCK_SH);
6921 }
6922 
6923 static const struct got_error *
6924 delete_ref(const char *name, struct got_repository *repo)
6925 {
6926 	const struct got_error *err;
6927 	struct got_reference *ref;
6928 
6929 	err = got_ref_open(&ref, repo, name, 0);
6930 	if (err) {
6931 		if (err->code == GOT_ERR_NOT_REF)
6932 			return NULL;
6933 		return err;
6934 	}
6935 
6936 	err = got_ref_delete(ref, repo);
6937 	got_ref_close(ref);
6938 	return err;
6939 }
6940 
6941 static const struct got_error *
6942 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
6943 {
6944 	const struct got_error *err;
6945 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
6946 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
6947 
6948 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6949 	if (err)
6950 		goto done;
6951 	err = delete_ref(tmp_branch_name, repo);
6952 	if (err)
6953 		goto done;
6954 
6955 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6956 	if (err)
6957 		goto done;
6958 	err = delete_ref(new_base_branch_ref_name, repo);
6959 	if (err)
6960 		goto done;
6961 
6962 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6963 	if (err)
6964 		goto done;
6965 	err = delete_ref(branch_ref_name, repo);
6966 	if (err)
6967 		goto done;
6968 
6969 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6970 	if (err)
6971 		goto done;
6972 	err = delete_ref(commit_ref_name, repo);
6973 	if (err)
6974 		goto done;
6975 
6976 done:
6977 	free(tmp_branch_name);
6978 	free(new_base_branch_ref_name);
6979 	free(branch_ref_name);
6980 	free(commit_ref_name);
6981 	return err;
6982 }
6983 
6984 static const struct got_error *
6985 create_backup_ref(const char *backup_ref_prefix, struct got_reference *branch,
6986     struct got_object_id *new_commit_id, struct got_repository *repo)
6987 {
6988 	const struct got_error *err;
6989 	struct got_reference *ref = NULL;
6990 	struct got_object_id *old_commit_id = NULL;
6991 	const char *branch_name = NULL;
6992 	char *new_id_str = NULL;
6993 	char *refname = NULL;
6994 
6995 	branch_name = got_ref_get_name(branch);
6996 	if (strncmp(branch_name, "refs/heads/", 11) != 0)
6997 		return got_error(GOT_ERR_BAD_REF_NAME); /* should not happen */
6998 	branch_name += 11;
6999 
7000 	err = got_object_id_str(&new_id_str, new_commit_id);
7001 	if (err)
7002 		return err;
7003 
7004 	if (asprintf(&refname, "%s/%s/%s", backup_ref_prefix, branch_name,
7005 	    new_id_str) == -1) {
7006 		err = got_error_from_errno("asprintf");
7007 		goto done;
7008 	}
7009 
7010 	err = got_ref_resolve(&old_commit_id, repo, branch);
7011 	if (err)
7012 		goto done;
7013 
7014 	err = got_ref_alloc(&ref, refname, old_commit_id);
7015 	if (err)
7016 		goto done;
7017 
7018 	err = got_ref_write(ref, repo);
7019 done:
7020 	free(new_id_str);
7021 	free(refname);
7022 	free(old_commit_id);
7023 	if (ref)
7024 		got_ref_close(ref);
7025 	return err;
7026 }
7027 
7028 const struct got_error *
7029 got_worktree_rebase_complete(struct got_worktree *worktree,
7030     struct got_fileindex *fileindex, struct got_reference *new_base_branch,
7031     struct got_reference *tmp_branch, struct got_reference *rebased_branch,
7032     struct got_repository *repo, int create_backup)
7033 {
7034 	const struct got_error *err, *unlockerr, *sync_err;
7035 	struct got_object_id *new_head_commit_id = NULL;
7036 	char *fileindex_path = NULL;
7037 
7038 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7039 	if (err)
7040 		return err;
7041 
7042 	if (create_backup) {
7043 		err = create_backup_ref(GOT_WORKTREE_REBASE_BACKUP_REF_PREFIX,
7044 		    rebased_branch, new_head_commit_id, repo);
7045 		if (err)
7046 			goto done;
7047 	}
7048 
7049 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
7050 	if (err)
7051 		goto done;
7052 
7053 	err = got_ref_write(rebased_branch, repo);
7054 	if (err)
7055 		goto done;
7056 
7057 	err = got_worktree_set_head_ref(worktree, rebased_branch);
7058 	if (err)
7059 		goto done;
7060 
7061 	err = delete_rebase_refs(worktree, repo);
7062 	if (err)
7063 		goto done;
7064 
7065 	err = get_fileindex_path(&fileindex_path, worktree);
7066 	if (err)
7067 		goto done;
7068 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7069 	sync_err = sync_fileindex(fileindex, fileindex_path);
7070 	if (sync_err && err == NULL)
7071 		err = sync_err;
7072 done:
7073 	got_fileindex_free(fileindex);
7074 	free(fileindex_path);
7075 	free(new_head_commit_id);
7076 	unlockerr = lock_worktree(worktree, LOCK_SH);
7077 	if (unlockerr && err == NULL)
7078 		err = unlockerr;
7079 	return err;
7080 }
7081 
7082 const struct got_error *
7083 got_worktree_rebase_abort(struct got_worktree *worktree,
7084     struct got_fileindex *fileindex, struct got_repository *repo,
7085     struct got_reference *new_base_branch,
7086     got_worktree_checkout_cb progress_cb, void *progress_arg)
7087 {
7088 	const struct got_error *err, *unlockerr, *sync_err;
7089 	struct got_reference *resolved = NULL;
7090 	struct got_object_id *commit_id = NULL;
7091 	struct got_commit_object *commit = NULL;
7092 	char *fileindex_path = NULL;
7093 	struct revert_file_args rfa;
7094 	struct got_object_id *tree_id = NULL;
7095 
7096 	err = lock_worktree(worktree, LOCK_EX);
7097 	if (err)
7098 		return err;
7099 
7100 	err = got_object_open_as_commit(&commit, repo,
7101 	    worktree->base_commit_id);
7102 	if (err)
7103 		goto done;
7104 
7105 	err = got_ref_open(&resolved, repo,
7106 	    got_ref_get_symref_target(new_base_branch), 0);
7107 	if (err)
7108 		goto done;
7109 
7110 	err = got_worktree_set_head_ref(worktree, resolved);
7111 	if (err)
7112 		goto done;
7113 
7114 	/*
7115 	 * XXX commits to the base branch could have happened while
7116 	 * we were busy rebasing; should we store the original commit ID
7117 	 * when rebase begins and read it back here?
7118 	 */
7119 	err = got_ref_resolve(&commit_id, repo, resolved);
7120 	if (err)
7121 		goto done;
7122 
7123 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7124 	if (err)
7125 		goto done;
7126 
7127 	err = got_object_id_by_path(&tree_id, repo, commit,
7128 	    worktree->path_prefix);
7129 	if (err)
7130 		goto done;
7131 
7132 	err = delete_rebase_refs(worktree, repo);
7133 	if (err)
7134 		goto done;
7135 
7136 	err = get_fileindex_path(&fileindex_path, worktree);
7137 	if (err)
7138 		goto done;
7139 
7140 	rfa.worktree = worktree;
7141 	rfa.fileindex = fileindex;
7142 	rfa.progress_cb = progress_cb;
7143 	rfa.progress_arg = progress_arg;
7144 	rfa.patch_cb = NULL;
7145 	rfa.patch_arg = NULL;
7146 	rfa.repo = repo;
7147 	rfa.unlink_added_files = 0;
7148 	err = worktree_status(worktree, "", fileindex, repo,
7149 	    revert_file, &rfa, NULL, NULL, 1, 0);
7150 	if (err)
7151 		goto sync;
7152 
7153 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7154 	    repo, progress_cb, progress_arg, NULL, NULL);
7155 sync:
7156 	sync_err = sync_fileindex(fileindex, fileindex_path);
7157 	if (sync_err && err == NULL)
7158 		err = sync_err;
7159 done:
7160 	got_ref_close(resolved);
7161 	free(tree_id);
7162 	free(commit_id);
7163 	if (commit)
7164 		got_object_commit_close(commit);
7165 	if (fileindex)
7166 		got_fileindex_free(fileindex);
7167 	free(fileindex_path);
7168 
7169 	unlockerr = lock_worktree(worktree, LOCK_SH);
7170 	if (unlockerr && err == NULL)
7171 		err = unlockerr;
7172 	return err;
7173 }
7174 
7175 const struct got_error *
7176 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
7177     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
7178     struct got_fileindex **fileindex, struct got_worktree *worktree,
7179     struct got_repository *repo)
7180 {
7181 	const struct got_error *err = NULL;
7182 	char *tmp_branch_name = NULL;
7183 	char *branch_ref_name = NULL;
7184 	char *base_commit_ref_name = NULL;
7185 	char *fileindex_path = NULL;
7186 	struct check_rebase_ok_arg ok_arg;
7187 	struct got_reference *wt_branch = NULL;
7188 	struct got_reference *base_commit_ref = NULL;
7189 
7190 	*tmp_branch = NULL;
7191 	*branch_ref = NULL;
7192 	*base_commit_id = NULL;
7193 	*fileindex = NULL;
7194 
7195 	err = lock_worktree(worktree, LOCK_EX);
7196 	if (err)
7197 		return err;
7198 
7199 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7200 	if (err)
7201 		goto done;
7202 
7203 	ok_arg.worktree = worktree;
7204 	ok_arg.repo = repo;
7205 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7206 	    &ok_arg);
7207 	if (err)
7208 		goto done;
7209 
7210 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7211 	if (err)
7212 		goto done;
7213 
7214 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7215 	if (err)
7216 		goto done;
7217 
7218 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7219 	    worktree);
7220 	if (err)
7221 		goto done;
7222 
7223 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
7224 	    0);
7225 	if (err)
7226 		goto done;
7227 
7228 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
7229 	if (err)
7230 		goto done;
7231 
7232 	err = got_ref_write(*branch_ref, repo);
7233 	if (err)
7234 		goto done;
7235 
7236 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
7237 	    worktree->base_commit_id);
7238 	if (err)
7239 		goto done;
7240 	err = got_ref_write(base_commit_ref, repo);
7241 	if (err)
7242 		goto done;
7243 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
7244 	if (*base_commit_id == NULL) {
7245 		err = got_error_from_errno("got_object_id_dup");
7246 		goto done;
7247 	}
7248 
7249 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
7250 	    worktree->base_commit_id);
7251 	if (err)
7252 		goto done;
7253 	err = got_ref_write(*tmp_branch, repo);
7254 	if (err)
7255 		goto done;
7256 
7257 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
7258 	if (err)
7259 		goto done;
7260 done:
7261 	free(fileindex_path);
7262 	free(tmp_branch_name);
7263 	free(branch_ref_name);
7264 	free(base_commit_ref_name);
7265 	if (wt_branch)
7266 		got_ref_close(wt_branch);
7267 	if (err) {
7268 		if (*branch_ref) {
7269 			got_ref_close(*branch_ref);
7270 			*branch_ref = NULL;
7271 		}
7272 		if (*tmp_branch) {
7273 			got_ref_close(*tmp_branch);
7274 			*tmp_branch = NULL;
7275 		}
7276 		free(*base_commit_id);
7277 		if (*fileindex) {
7278 			got_fileindex_free(*fileindex);
7279 			*fileindex = NULL;
7280 		}
7281 		lock_worktree(worktree, LOCK_SH);
7282 	}
7283 	return err;
7284 }
7285 
7286 const struct got_error *
7287 got_worktree_histedit_postpone(struct got_worktree *worktree,
7288     struct got_fileindex *fileindex)
7289 {
7290 	if (fileindex)
7291 		got_fileindex_free(fileindex);
7292 	return lock_worktree(worktree, LOCK_SH);
7293 }
7294 
7295 const struct got_error *
7296 got_worktree_histedit_in_progress(int *in_progress,
7297     struct got_worktree *worktree)
7298 {
7299 	const struct got_error *err;
7300 	char *tmp_branch_name = NULL;
7301 
7302 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7303 	if (err)
7304 		return err;
7305 
7306 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
7307 	free(tmp_branch_name);
7308 	return NULL;
7309 }
7310 
7311 const struct got_error *
7312 got_worktree_histedit_continue(struct got_object_id **commit_id,
7313     struct got_reference **tmp_branch, struct got_reference **branch_ref,
7314     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
7315     struct got_worktree *worktree, struct got_repository *repo)
7316 {
7317 	const struct got_error *err;
7318 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
7319 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
7320 	struct got_reference *commit_ref = NULL;
7321 	struct got_reference *base_commit_ref = NULL;
7322 	char *fileindex_path = NULL;
7323 	int have_staged_files = 0;
7324 
7325 	*commit_id = NULL;
7326 	*tmp_branch = NULL;
7327 	*base_commit_id = NULL;
7328 	*fileindex = NULL;
7329 
7330 	err = lock_worktree(worktree, LOCK_EX);
7331 	if (err)
7332 		return err;
7333 
7334 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7335 	if (err)
7336 		goto done;
7337 
7338 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
7339 	    &have_staged_files);
7340 	if (err && err->code != GOT_ERR_CANCELLED)
7341 		goto done;
7342 	if (have_staged_files) {
7343 		err = got_error(GOT_ERR_STAGED_PATHS);
7344 		goto done;
7345 	}
7346 
7347 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7348 	if (err)
7349 		goto done;
7350 
7351 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7352 	if (err)
7353 		goto done;
7354 
7355 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7356 	if (err)
7357 		goto done;
7358 
7359 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7360 	    worktree);
7361 	if (err)
7362 		goto done;
7363 
7364 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
7365 	if (err)
7366 		goto done;
7367 
7368 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
7369 	if (err)
7370 		goto done;
7371 	err = got_ref_resolve(commit_id, repo, commit_ref);
7372 	if (err)
7373 		goto done;
7374 
7375 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
7376 	if (err)
7377 		goto done;
7378 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
7379 	if (err)
7380 		goto done;
7381 
7382 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
7383 	if (err)
7384 		goto done;
7385 done:
7386 	free(commit_ref_name);
7387 	free(branch_ref_name);
7388 	free(fileindex_path);
7389 	if (commit_ref)
7390 		got_ref_close(commit_ref);
7391 	if (base_commit_ref)
7392 		got_ref_close(base_commit_ref);
7393 	if (err) {
7394 		free(*commit_id);
7395 		*commit_id = NULL;
7396 		free(*base_commit_id);
7397 		*base_commit_id = NULL;
7398 		if (*tmp_branch) {
7399 			got_ref_close(*tmp_branch);
7400 			*tmp_branch = NULL;
7401 		}
7402 		if (*fileindex) {
7403 			got_fileindex_free(*fileindex);
7404 			*fileindex = NULL;
7405 		}
7406 		lock_worktree(worktree, LOCK_EX);
7407 	}
7408 	return err;
7409 }
7410 
7411 static const struct got_error *
7412 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
7413 {
7414 	const struct got_error *err;
7415 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
7416 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
7417 
7418 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7419 	if (err)
7420 		goto done;
7421 	err = delete_ref(tmp_branch_name, repo);
7422 	if (err)
7423 		goto done;
7424 
7425 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7426 	    worktree);
7427 	if (err)
7428 		goto done;
7429 	err = delete_ref(base_commit_ref_name, repo);
7430 	if (err)
7431 		goto done;
7432 
7433 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7434 	if (err)
7435 		goto done;
7436 	err = delete_ref(branch_ref_name, repo);
7437 	if (err)
7438 		goto done;
7439 
7440 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7441 	if (err)
7442 		goto done;
7443 	err = delete_ref(commit_ref_name, repo);
7444 	if (err)
7445 		goto done;
7446 done:
7447 	free(tmp_branch_name);
7448 	free(base_commit_ref_name);
7449 	free(branch_ref_name);
7450 	free(commit_ref_name);
7451 	return err;
7452 }
7453 
7454 const struct got_error *
7455 got_worktree_histedit_abort(struct got_worktree *worktree,
7456     struct got_fileindex *fileindex, struct got_repository *repo,
7457     struct got_reference *branch, struct got_object_id *base_commit_id,
7458     got_worktree_checkout_cb progress_cb, void *progress_arg)
7459 {
7460 	const struct got_error *err, *unlockerr, *sync_err;
7461 	struct got_reference *resolved = NULL;
7462 	char *fileindex_path = NULL;
7463 	struct got_commit_object *commit = NULL;
7464 	struct got_object_id *tree_id = NULL;
7465 	struct revert_file_args rfa;
7466 
7467 	err = lock_worktree(worktree, LOCK_EX);
7468 	if (err)
7469 		return err;
7470 
7471 	err = got_object_open_as_commit(&commit, repo,
7472 	    worktree->base_commit_id);
7473 	if (err)
7474 		goto done;
7475 
7476 	err = got_ref_open(&resolved, repo,
7477 	    got_ref_get_symref_target(branch), 0);
7478 	if (err)
7479 		goto done;
7480 
7481 	err = got_worktree_set_head_ref(worktree, resolved);
7482 	if (err)
7483 		goto done;
7484 
7485 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
7486 	if (err)
7487 		goto done;
7488 
7489 	err = got_object_id_by_path(&tree_id, repo, commit,
7490 	    worktree->path_prefix);
7491 	if (err)
7492 		goto done;
7493 
7494 	err = delete_histedit_refs(worktree, repo);
7495 	if (err)
7496 		goto done;
7497 
7498 	err = get_fileindex_path(&fileindex_path, worktree);
7499 	if (err)
7500 		goto done;
7501 
7502 	rfa.worktree = worktree;
7503 	rfa.fileindex = fileindex;
7504 	rfa.progress_cb = progress_cb;
7505 	rfa.progress_arg = progress_arg;
7506 	rfa.patch_cb = NULL;
7507 	rfa.patch_arg = NULL;
7508 	rfa.repo = repo;
7509 	rfa.unlink_added_files = 0;
7510 	err = worktree_status(worktree, "", fileindex, repo,
7511 	    revert_file, &rfa, NULL, NULL, 1, 0);
7512 	if (err)
7513 		goto sync;
7514 
7515 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7516 	    repo, progress_cb, progress_arg, NULL, NULL);
7517 sync:
7518 	sync_err = sync_fileindex(fileindex, fileindex_path);
7519 	if (sync_err && err == NULL)
7520 		err = sync_err;
7521 done:
7522 	got_ref_close(resolved);
7523 	free(tree_id);
7524 	free(fileindex_path);
7525 
7526 	unlockerr = lock_worktree(worktree, LOCK_SH);
7527 	if (unlockerr && err == NULL)
7528 		err = unlockerr;
7529 	return err;
7530 }
7531 
7532 const struct got_error *
7533 got_worktree_histedit_complete(struct got_worktree *worktree,
7534     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
7535     struct got_reference *edited_branch, struct got_repository *repo)
7536 {
7537 	const struct got_error *err, *unlockerr, *sync_err;
7538 	struct got_object_id *new_head_commit_id = NULL;
7539 	struct got_reference *resolved = NULL;
7540 	char *fileindex_path = NULL;
7541 
7542 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7543 	if (err)
7544 		return err;
7545 
7546 	err = got_ref_open(&resolved, repo,
7547 	    got_ref_get_symref_target(edited_branch), 0);
7548 	if (err)
7549 		goto done;
7550 
7551 	err = create_backup_ref(GOT_WORKTREE_HISTEDIT_BACKUP_REF_PREFIX,
7552 	    resolved, new_head_commit_id, repo);
7553 	if (err)
7554 		goto done;
7555 
7556 	err = got_ref_change_ref(resolved, new_head_commit_id);
7557 	if (err)
7558 		goto done;
7559 
7560 	err = got_ref_write(resolved, repo);
7561 	if (err)
7562 		goto done;
7563 
7564 	err = got_worktree_set_head_ref(worktree, resolved);
7565 	if (err)
7566 		goto done;
7567 
7568 	err = delete_histedit_refs(worktree, repo);
7569 	if (err)
7570 		goto done;
7571 
7572 	err = get_fileindex_path(&fileindex_path, worktree);
7573 	if (err)
7574 		goto done;
7575 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7576 	sync_err = sync_fileindex(fileindex, fileindex_path);
7577 	if (sync_err && err == NULL)
7578 		err = sync_err;
7579 done:
7580 	got_fileindex_free(fileindex);
7581 	free(fileindex_path);
7582 	free(new_head_commit_id);
7583 	unlockerr = lock_worktree(worktree, LOCK_SH);
7584 	if (unlockerr && err == NULL)
7585 		err = unlockerr;
7586 	return err;
7587 }
7588 
7589 const struct got_error *
7590 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
7591     struct got_object_id *commit_id, struct got_repository *repo)
7592 {
7593 	const struct got_error *err;
7594 	char *commit_ref_name;
7595 
7596 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7597 	if (err)
7598 		return err;
7599 
7600 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
7601 	if (err)
7602 		goto done;
7603 
7604 	err = delete_ref(commit_ref_name, repo);
7605 done:
7606 	free(commit_ref_name);
7607 	return err;
7608 }
7609 
7610 const struct got_error *
7611 got_worktree_integrate_prepare(struct got_fileindex **fileindex,
7612     struct got_reference **branch_ref, struct got_reference **base_branch_ref,
7613     struct got_worktree *worktree, const char *refname,
7614     struct got_repository *repo)
7615 {
7616 	const struct got_error *err = NULL;
7617 	char *fileindex_path = NULL;
7618 	struct check_rebase_ok_arg ok_arg;
7619 
7620 	*fileindex = NULL;
7621 	*branch_ref = NULL;
7622 	*base_branch_ref = NULL;
7623 
7624 	err = lock_worktree(worktree, LOCK_EX);
7625 	if (err)
7626 		return err;
7627 
7628 	if (strcmp(refname, got_worktree_get_head_ref_name(worktree)) == 0) {
7629 		err = got_error_msg(GOT_ERR_SAME_BRANCH,
7630 		    "cannot integrate a branch into itself; "
7631 		    "update -b or different branch name required");
7632 		goto done;
7633 	}
7634 
7635 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7636 	if (err)
7637 		goto done;
7638 
7639 	/* Preconditions are the same as for rebase. */
7640 	ok_arg.worktree = worktree;
7641 	ok_arg.repo = repo;
7642 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7643 	    &ok_arg);
7644 	if (err)
7645 		goto done;
7646 
7647 	err = got_ref_open(branch_ref, repo, refname, 1);
7648 	if (err)
7649 		goto done;
7650 
7651 	err = got_ref_open(base_branch_ref, repo,
7652 	    got_worktree_get_head_ref_name(worktree), 1);
7653 done:
7654 	if (err) {
7655 		if (*branch_ref) {
7656 			got_ref_close(*branch_ref);
7657 			*branch_ref = NULL;
7658 		}
7659 		if (*base_branch_ref) {
7660 			got_ref_close(*base_branch_ref);
7661 			*base_branch_ref = NULL;
7662 		}
7663 		if (*fileindex) {
7664 			got_fileindex_free(*fileindex);
7665 			*fileindex = NULL;
7666 		}
7667 		lock_worktree(worktree, LOCK_SH);
7668 	}
7669 	return err;
7670 }
7671 
7672 const struct got_error *
7673 got_worktree_integrate_continue(struct got_worktree *worktree,
7674     struct got_fileindex *fileindex, struct got_repository *repo,
7675     struct got_reference *branch_ref, struct got_reference *base_branch_ref,
7676     got_worktree_checkout_cb progress_cb, void *progress_arg,
7677     got_cancel_cb cancel_cb, void *cancel_arg)
7678 {
7679 	const struct got_error *err = NULL, *sync_err, *unlockerr;
7680 	char *fileindex_path = NULL;
7681 	struct got_object_id *tree_id = NULL, *commit_id = NULL;
7682 	struct got_commit_object *commit =  NULL;
7683 
7684 	err = get_fileindex_path(&fileindex_path, worktree);
7685 	if (err)
7686 		goto done;
7687 
7688 	err = got_ref_resolve(&commit_id, repo, branch_ref);
7689 	if (err)
7690 		goto done;
7691 
7692 	err = got_object_open_as_commit(&commit, repo, commit_id);
7693 	if (err)
7694 		goto done;
7695 
7696 	err = got_object_id_by_path(&tree_id, repo, commit,
7697 	    worktree->path_prefix);
7698 	if (err)
7699 		goto done;
7700 
7701 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7702 	if (err)
7703 		goto done;
7704 
7705 	err = checkout_files(worktree, fileindex, "", tree_id, NULL, repo,
7706 	    progress_cb, progress_arg, cancel_cb, cancel_arg);
7707 	if (err)
7708 		goto sync;
7709 
7710 	err = got_ref_change_ref(base_branch_ref, commit_id);
7711 	if (err)
7712 		goto sync;
7713 
7714 	err = got_ref_write(base_branch_ref, repo);
7715 	if (err)
7716 		goto sync;
7717 
7718 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7719 sync:
7720 	sync_err = sync_fileindex(fileindex, fileindex_path);
7721 	if (sync_err && err == NULL)
7722 		err = sync_err;
7723 
7724 done:
7725 	unlockerr = got_ref_unlock(branch_ref);
7726 	if (unlockerr && err == NULL)
7727 		err = unlockerr;
7728 	got_ref_close(branch_ref);
7729 
7730 	unlockerr = got_ref_unlock(base_branch_ref);
7731 	if (unlockerr && err == NULL)
7732 		err = unlockerr;
7733 	got_ref_close(base_branch_ref);
7734 
7735 	got_fileindex_free(fileindex);
7736 	free(fileindex_path);
7737 	free(tree_id);
7738 	if (commit)
7739 		got_object_commit_close(commit);
7740 
7741 	unlockerr = lock_worktree(worktree, LOCK_SH);
7742 	if (unlockerr && err == NULL)
7743 		err = unlockerr;
7744 	return err;
7745 }
7746 
7747 const struct got_error *
7748 got_worktree_integrate_abort(struct got_worktree *worktree,
7749     struct got_fileindex *fileindex, struct got_repository *repo,
7750     struct got_reference *branch_ref, struct got_reference *base_branch_ref)
7751 {
7752 	const struct got_error *err = NULL, *unlockerr = NULL;
7753 
7754 	got_fileindex_free(fileindex);
7755 
7756 	err = lock_worktree(worktree, LOCK_SH);
7757 
7758 	unlockerr = got_ref_unlock(branch_ref);
7759 	if (unlockerr && err == NULL)
7760 		err = unlockerr;
7761 	got_ref_close(branch_ref);
7762 
7763 	unlockerr = got_ref_unlock(base_branch_ref);
7764 	if (unlockerr && err == NULL)
7765 		err = unlockerr;
7766 	got_ref_close(base_branch_ref);
7767 
7768 	return err;
7769 }
7770 
7771 const struct got_error *
7772 got_worktree_merge_postpone(struct got_worktree *worktree,
7773     struct got_fileindex *fileindex)
7774 {
7775 	const struct got_error *err, *sync_err;
7776 	char *fileindex_path = NULL;
7777 
7778 	err = get_fileindex_path(&fileindex_path, worktree);
7779 	if (err)
7780 		goto done;
7781 
7782 	sync_err = sync_fileindex(fileindex, fileindex_path);
7783 
7784 	err = lock_worktree(worktree, LOCK_SH);
7785 	if (sync_err && err == NULL)
7786 		err = sync_err;
7787 done:
7788 	got_fileindex_free(fileindex);
7789 	free(fileindex_path);
7790 	return err;
7791 }
7792 
7793 static const struct got_error *
7794 delete_merge_refs(struct got_worktree *worktree, struct got_repository *repo)
7795 {
7796 	const struct got_error *err;
7797 	char *branch_refname = NULL, *commit_refname = NULL;
7798 
7799 	err = get_merge_branch_ref_name(&branch_refname, worktree);
7800 	if (err)
7801 		goto done;
7802 	err = delete_ref(branch_refname, repo);
7803 	if (err)
7804 		goto done;
7805 
7806 	err = get_merge_commit_ref_name(&commit_refname, worktree);
7807 	if (err)
7808 		goto done;
7809 	err = delete_ref(commit_refname, repo);
7810 	if (err)
7811 		goto done;
7812 
7813 done:
7814 	free(branch_refname);
7815 	free(commit_refname);
7816 	return err;
7817 }
7818 
7819 struct merge_commit_msg_arg {
7820 	struct got_worktree *worktree;
7821 	const char *branch_name;
7822 };
7823 
7824 static const struct got_error *
7825 merge_commit_msg_cb(struct got_pathlist_head *commitable_paths,
7826     const char *diff_path, char **logmsg, void *arg)
7827 {
7828 	struct merge_commit_msg_arg *a = arg;
7829 
7830 	if (asprintf(logmsg, "merge %s into %s\n", a->branch_name,
7831 	    got_worktree_get_head_ref_name(a->worktree)) == -1)
7832 		return got_error_from_errno("asprintf");
7833 
7834 	return NULL;
7835 }
7836 
7837 
7838 const struct got_error *
7839 got_worktree_merge_branch(struct got_worktree *worktree,
7840     struct got_fileindex *fileindex,
7841     struct got_object_id *yca_commit_id,
7842     struct got_object_id *branch_tip,
7843     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
7844     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
7845 {
7846 	const struct got_error *err;
7847 	char *fileindex_path = NULL;
7848 
7849 	err = get_fileindex_path(&fileindex_path, worktree);
7850 	if (err)
7851 		goto done;
7852 
7853 	err = got_fileindex_for_each_entry_safe(fileindex, check_mixed_commits,
7854 	    worktree);
7855 	if (err)
7856 		goto done;
7857 
7858 	err = merge_files(worktree, fileindex, fileindex_path, yca_commit_id,
7859 	    branch_tip, repo, progress_cb, progress_arg,
7860 	    cancel_cb, cancel_arg);
7861 done:
7862 	free(fileindex_path);
7863 	return err;
7864 }
7865 
7866 const struct got_error *
7867 got_worktree_merge_commit(struct got_object_id **new_commit_id,
7868     struct got_worktree *worktree, struct got_fileindex *fileindex,
7869     const char *author, const char *committer, int allow_bad_symlinks,
7870     struct got_object_id *branch_tip, const char *branch_name,
7871     struct got_repository *repo,
7872     got_worktree_status_cb status_cb, void *status_arg)
7873 
7874 {
7875 	const struct got_error *err = NULL, *sync_err;
7876 	struct got_pathlist_head commitable_paths;
7877 	struct collect_commitables_arg cc_arg;
7878 	struct got_pathlist_entry *pe;
7879 	struct got_reference *head_ref = NULL;
7880 	struct got_object_id *head_commit_id = NULL;
7881 	int have_staged_files = 0;
7882 	struct merge_commit_msg_arg mcm_arg;
7883 	char *fileindex_path = NULL;
7884 
7885 	memset(&cc_arg, 0, sizeof(cc_arg));
7886 	*new_commit_id = NULL;
7887 
7888 	TAILQ_INIT(&commitable_paths);
7889 
7890 	err = get_fileindex_path(&fileindex_path, worktree);
7891 	if (err)
7892 		goto done;
7893 
7894 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
7895 	if (err)
7896 		goto done;
7897 
7898 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
7899 	if (err)
7900 		goto done;
7901 
7902 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
7903 	    &have_staged_files);
7904 	if (err && err->code != GOT_ERR_CANCELLED)
7905 		goto done;
7906 	if (have_staged_files) {
7907 		err = got_error(GOT_ERR_MERGE_STAGED_PATHS);
7908 		goto done;
7909 	}
7910 
7911 	cc_arg.commitable_paths = &commitable_paths;
7912 	cc_arg.worktree = worktree;
7913 	cc_arg.fileindex = fileindex;
7914 	cc_arg.repo = repo;
7915 	cc_arg.have_staged_files = have_staged_files;
7916 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
7917 	err = worktree_status(worktree, "", fileindex, repo,
7918 	    collect_commitables, &cc_arg, NULL, NULL, 1, 0);
7919 	if (err)
7920 		goto done;
7921 
7922 	if (TAILQ_EMPTY(&commitable_paths)) {
7923 		err = got_error_fmt(GOT_ERR_COMMIT_NO_CHANGES,
7924 		    "merge of %s cannot proceed", branch_name);
7925 		goto done;
7926 	}
7927 
7928 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
7929 		struct got_commitable *ct = pe->data;
7930 		const char *ct_path = ct->in_repo_path;
7931 
7932 		while (ct_path[0] == '/')
7933 			ct_path++;
7934 		err = check_out_of_date(ct_path, ct->status,
7935 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
7936 		    head_commit_id, repo, GOT_ERR_MERGE_COMMIT_OUT_OF_DATE);
7937 		if (err)
7938 			goto done;
7939 
7940 	}
7941 
7942 	mcm_arg.worktree = worktree;
7943 	mcm_arg.branch_name = branch_name;
7944 	err = commit_worktree(new_commit_id, &commitable_paths,
7945 	    head_commit_id, branch_tip, worktree, author, committer, NULL,
7946 	    merge_commit_msg_cb, &mcm_arg, status_cb, status_arg, repo);
7947 	if (err)
7948 		goto done;
7949 
7950 	err = update_fileindex_after_commit(worktree, &commitable_paths,
7951 	    *new_commit_id, fileindex, have_staged_files);
7952 	sync_err = sync_fileindex(fileindex, fileindex_path);
7953 	if (sync_err && err == NULL)
7954 		err = sync_err;
7955 done:
7956 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
7957 		struct got_commitable *ct = pe->data;
7958 		free_commitable(ct);
7959 	}
7960 	got_pathlist_free(&commitable_paths);
7961 	free(fileindex_path);
7962 	return err;
7963 }
7964 
7965 const struct got_error *
7966 got_worktree_merge_complete(struct got_worktree *worktree,
7967     struct got_fileindex *fileindex, struct got_repository *repo)
7968 {
7969 	const struct got_error *err, *unlockerr, *sync_err;
7970 	char *fileindex_path = NULL;
7971 
7972 	err = delete_merge_refs(worktree, repo);
7973 	if (err)
7974 		goto done;
7975 
7976 	err = get_fileindex_path(&fileindex_path, worktree);
7977 	if (err)
7978 		goto done;
7979 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7980 	sync_err = sync_fileindex(fileindex, fileindex_path);
7981 	if (sync_err && err == NULL)
7982 		err = sync_err;
7983 done:
7984 	got_fileindex_free(fileindex);
7985 	free(fileindex_path);
7986 	unlockerr = lock_worktree(worktree, LOCK_SH);
7987 	if (unlockerr && err == NULL)
7988 		err = unlockerr;
7989 	return err;
7990 }
7991 
7992 const struct got_error *
7993 got_worktree_merge_in_progress(int *in_progress, struct got_worktree *worktree,
7994     struct got_repository *repo)
7995 {
7996 	const struct got_error *err;
7997 	char *branch_refname = NULL;
7998 	struct got_reference *branch_ref = NULL;
7999 
8000 	*in_progress = 0;
8001 
8002 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8003 	if (err)
8004 		return err;
8005 	err = got_ref_open(&branch_ref, repo, branch_refname, 0);
8006 	free(branch_refname);
8007 	if (err) {
8008 		if (err->code != GOT_ERR_NOT_REF)
8009 			return err;
8010 	} else
8011 		*in_progress = 1;
8012 
8013 	return NULL;
8014 }
8015 
8016 const struct got_error *got_worktree_merge_prepare(
8017     struct got_fileindex **fileindex, struct got_worktree *worktree,
8018     struct got_reference *branch, struct got_repository *repo)
8019 {
8020 	const struct got_error *err = NULL;
8021 	char *fileindex_path = NULL;
8022 	char *branch_refname = NULL, *commit_refname = NULL;
8023 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
8024 	struct got_reference *commit_ref = NULL;
8025 	struct got_object_id *branch_tip = NULL, *wt_branch_tip = NULL;
8026 	struct check_rebase_ok_arg ok_arg;
8027 
8028 	*fileindex = NULL;
8029 
8030 	err = lock_worktree(worktree, LOCK_EX);
8031 	if (err)
8032 		return err;
8033 
8034 	err = open_fileindex(fileindex, &fileindex_path, worktree);
8035 	if (err)
8036 		goto done;
8037 
8038 	/* Preconditions are the same as for rebase. */
8039 	ok_arg.worktree = worktree;
8040 	ok_arg.repo = repo;
8041 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
8042 	    &ok_arg);
8043 	if (err)
8044 		goto done;
8045 
8046 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8047 	if (err)
8048 		return err;
8049 
8050 	err = get_merge_commit_ref_name(&commit_refname, worktree);
8051 	if (err)
8052 		return err;
8053 
8054 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
8055 	    0);
8056 	if (err)
8057 		goto done;
8058 
8059 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
8060 	if (err)
8061 		goto done;
8062 
8063 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
8064 		err = got_error(GOT_ERR_MERGE_OUT_OF_DATE);
8065 		goto done;
8066 	}
8067 
8068 	err = got_ref_resolve(&branch_tip, repo, branch);
8069 	if (err)
8070 		goto done;
8071 
8072 	err = got_ref_alloc_symref(&branch_ref, branch_refname, branch);
8073 	if (err)
8074 		goto done;
8075 	err = got_ref_write(branch_ref, repo);
8076 	if (err)
8077 		goto done;
8078 
8079 	err = got_ref_alloc(&commit_ref, commit_refname, branch_tip);
8080 	if (err)
8081 		goto done;
8082 	err = got_ref_write(commit_ref, repo);
8083 	if (err)
8084 		goto done;
8085 
8086 done:
8087 	free(branch_refname);
8088 	free(commit_refname);
8089 	free(fileindex_path);
8090 	if (branch_ref)
8091 		got_ref_close(branch_ref);
8092 	if (commit_ref)
8093 		got_ref_close(commit_ref);
8094 	if (wt_branch)
8095 		got_ref_close(wt_branch);
8096 	free(wt_branch_tip);
8097 	if (err) {
8098 		if (*fileindex) {
8099 			got_fileindex_free(*fileindex);
8100 			*fileindex = NULL;
8101 		}
8102 		lock_worktree(worktree, LOCK_SH);
8103 	}
8104 	return err;
8105 }
8106 
8107 const struct got_error *
8108 got_worktree_merge_continue(char **branch_name,
8109     struct got_object_id **branch_tip, struct got_fileindex **fileindex,
8110     struct got_worktree *worktree, struct got_repository *repo)
8111 {
8112 	const struct got_error *err;
8113 	char *commit_refname = NULL, *branch_refname = NULL;
8114 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
8115 	char *fileindex_path = NULL;
8116 	int have_staged_files = 0;
8117 
8118 	*branch_name = NULL;
8119 	*branch_tip = NULL;
8120 	*fileindex = NULL;
8121 
8122 	err = lock_worktree(worktree, LOCK_EX);
8123 	if (err)
8124 		return err;
8125 
8126 	err = open_fileindex(fileindex, &fileindex_path, worktree);
8127 	if (err)
8128 		goto done;
8129 
8130 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
8131 	    &have_staged_files);
8132 	if (err && err->code != GOT_ERR_CANCELLED)
8133 		goto done;
8134 	if (have_staged_files) {
8135 		err = got_error(GOT_ERR_STAGED_PATHS);
8136 		goto done;
8137 	}
8138 
8139 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8140 	if (err)
8141 		goto done;
8142 
8143 	err = get_merge_commit_ref_name(&commit_refname, worktree);
8144 	if (err)
8145 		goto done;
8146 
8147 	err = got_ref_open(&branch_ref, repo, branch_refname, 0);
8148 	if (err)
8149 		goto done;
8150 
8151 	if (!got_ref_is_symbolic(branch_ref)) {
8152 		err = got_error_fmt(GOT_ERR_BAD_REF_TYPE,
8153 		    "%s is not a symbolic reference",
8154 		    got_ref_get_name(branch_ref));
8155 		goto done;
8156 	}
8157 	*branch_name = strdup(got_ref_get_symref_target(branch_ref));
8158 	if (*branch_name == NULL) {
8159 		err = got_error_from_errno("strdup");
8160 		goto done;
8161 	}
8162 
8163 	err = got_ref_open(&commit_ref, repo, commit_refname, 0);
8164 	if (err)
8165 		goto done;
8166 
8167 	err = got_ref_resolve(branch_tip, repo, commit_ref);
8168 	if (err)
8169 		goto done;
8170 done:
8171 	free(commit_refname);
8172 	free(branch_refname);
8173 	free(fileindex_path);
8174 	if (commit_ref)
8175 		got_ref_close(commit_ref);
8176 	if (branch_ref)
8177 		got_ref_close(branch_ref);
8178 	if (err) {
8179 		if (*branch_name) {
8180 			free(*branch_name);
8181 			*branch_name = NULL;
8182 		}
8183 		free(*branch_tip);
8184 		*branch_tip = NULL;
8185 		if (*fileindex) {
8186 			got_fileindex_free(*fileindex);
8187 			*fileindex = NULL;
8188 		}
8189 		lock_worktree(worktree, LOCK_SH);
8190 	}
8191 	return err;
8192 }
8193 
8194 const struct got_error *
8195 got_worktree_merge_abort(struct got_worktree *worktree,
8196     struct got_fileindex *fileindex, struct got_repository *repo,
8197     got_worktree_checkout_cb progress_cb, void *progress_arg)
8198 {
8199 	const struct got_error *err, *unlockerr, *sync_err;
8200 	struct got_object_id *commit_id = NULL;
8201 	struct got_commit_object *commit = NULL;
8202 	char *fileindex_path = NULL;
8203 	struct revert_file_args rfa;
8204 	struct got_object_id *tree_id = NULL;
8205 
8206 	err = got_object_open_as_commit(&commit, repo,
8207 	    worktree->base_commit_id);
8208 	if (err)
8209 		goto done;
8210 
8211 	err = got_object_id_by_path(&tree_id, repo, commit,
8212 	    worktree->path_prefix);
8213 	if (err)
8214 		goto done;
8215 
8216 	err = delete_merge_refs(worktree, repo);
8217 	if (err)
8218 		goto done;
8219 
8220 	err = get_fileindex_path(&fileindex_path, worktree);
8221 	if (err)
8222 		goto done;
8223 
8224 	rfa.worktree = worktree;
8225 	rfa.fileindex = fileindex;
8226 	rfa.progress_cb = progress_cb;
8227 	rfa.progress_arg = progress_arg;
8228 	rfa.patch_cb = NULL;
8229 	rfa.patch_arg = NULL;
8230 	rfa.repo = repo;
8231 	rfa.unlink_added_files = 1;
8232 	err = worktree_status(worktree, "", fileindex, repo,
8233 	    revert_file, &rfa, NULL, NULL, 1, 0);
8234 	if (err)
8235 		goto sync;
8236 
8237 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
8238 	    repo, progress_cb, progress_arg, NULL, NULL);
8239 sync:
8240 	sync_err = sync_fileindex(fileindex, fileindex_path);
8241 	if (sync_err && err == NULL)
8242 		err = sync_err;
8243 done:
8244 	free(tree_id);
8245 	free(commit_id);
8246 	if (commit)
8247 		got_object_commit_close(commit);
8248 	if (fileindex)
8249 		got_fileindex_free(fileindex);
8250 	free(fileindex_path);
8251 
8252 	unlockerr = lock_worktree(worktree, LOCK_SH);
8253 	if (unlockerr && err == NULL)
8254 		err = unlockerr;
8255 	return err;
8256 }
8257 
8258 struct check_stage_ok_arg {
8259 	struct got_object_id *head_commit_id;
8260 	struct got_worktree *worktree;
8261 	struct got_fileindex *fileindex;
8262 	struct got_repository *repo;
8263 	int have_changes;
8264 };
8265 
8266 static const struct got_error *
8267 check_stage_ok(void *arg, unsigned char status,
8268     unsigned char staged_status, const char *relpath,
8269     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8270     struct got_object_id *commit_id, int dirfd, const char *de_name)
8271 {
8272 	struct check_stage_ok_arg *a = arg;
8273 	const struct got_error *err = NULL;
8274 	struct got_fileindex_entry *ie;
8275 	struct got_object_id base_commit_id;
8276 	struct got_object_id *base_commit_idp = NULL;
8277 	char *in_repo_path = NULL, *p;
8278 
8279 	if (status == GOT_STATUS_UNVERSIONED ||
8280 	    status == GOT_STATUS_NO_CHANGE)
8281 		return NULL;
8282 	if (status == GOT_STATUS_NONEXISTENT)
8283 		return got_error_set_errno(ENOENT, relpath);
8284 
8285 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8286 	if (ie == NULL)
8287 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8288 
8289 	if (asprintf(&in_repo_path, "%s%s%s", a->worktree->path_prefix,
8290 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
8291 	    relpath) == -1)
8292 		return got_error_from_errno("asprintf");
8293 
8294 	if (got_fileindex_entry_has_commit(ie)) {
8295 		memcpy(base_commit_id.sha1, ie->commit_sha1,
8296 		    SHA1_DIGEST_LENGTH);
8297 		base_commit_idp = &base_commit_id;
8298 	}
8299 
8300 	if (status == GOT_STATUS_CONFLICT) {
8301 		err = got_error_path(ie->path, GOT_ERR_STAGE_CONFLICT);
8302 		goto done;
8303 	} else if (status != GOT_STATUS_ADD &&
8304 	    status != GOT_STATUS_MODIFY &&
8305 	    status != GOT_STATUS_DELETE) {
8306 		err = got_error_path(ie->path, GOT_ERR_FILE_STATUS);
8307 		goto done;
8308 	}
8309 
8310 	a->have_changes = 1;
8311 
8312 	p = in_repo_path;
8313 	while (p[0] == '/')
8314 		p++;
8315 	err = check_out_of_date(p, status, staged_status,
8316 	    blob_id, base_commit_idp, a->head_commit_id, a->repo,
8317 	    GOT_ERR_STAGE_OUT_OF_DATE);
8318 done:
8319 	free(in_repo_path);
8320 	return err;
8321 }
8322 
8323 struct stage_path_arg {
8324 	struct got_worktree *worktree;
8325 	struct got_fileindex *fileindex;
8326 	struct got_repository *repo;
8327 	got_worktree_status_cb status_cb;
8328 	void *status_arg;
8329 	got_worktree_patch_cb patch_cb;
8330 	void *patch_arg;
8331 	int staged_something;
8332 	int allow_bad_symlinks;
8333 };
8334 
8335 static const struct got_error *
8336 stage_path(void *arg, unsigned char status,
8337     unsigned char staged_status, const char *relpath,
8338     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8339     struct got_object_id *commit_id, int dirfd, const char *de_name)
8340 {
8341 	struct stage_path_arg *a = arg;
8342 	const struct got_error *err = NULL;
8343 	struct got_fileindex_entry *ie;
8344 	char *ondisk_path = NULL, *path_content = NULL;
8345 	uint32_t stage;
8346 	struct got_object_id *new_staged_blob_id = NULL;
8347 	struct stat sb;
8348 
8349 	if (status == GOT_STATUS_UNVERSIONED)
8350 		return NULL;
8351 
8352 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8353 	if (ie == NULL)
8354 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8355 
8356 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
8357 	    relpath)== -1)
8358 		return got_error_from_errno("asprintf");
8359 
8360 	switch (status) {
8361 	case GOT_STATUS_ADD:
8362 	case GOT_STATUS_MODIFY:
8363 		/* XXX could sb.st_mode be passed in by our caller? */
8364 		if (lstat(ondisk_path, &sb) == -1) {
8365 			err = got_error_from_errno2("lstat", ondisk_path);
8366 			break;
8367 		}
8368 		if (a->patch_cb) {
8369 			if (status == GOT_STATUS_ADD) {
8370 				int choice = GOT_PATCH_CHOICE_NONE;
8371 				err = (*a->patch_cb)(&choice, a->patch_arg,
8372 				    status, ie->path, NULL, 1, 1);
8373 				if (err)
8374 					break;
8375 				if (choice != GOT_PATCH_CHOICE_YES)
8376 					break;
8377 			} else {
8378 				err = create_patched_content(&path_content, 0,
8379 				    staged_blob_id ? staged_blob_id : blob_id,
8380 				    ondisk_path, dirfd, de_name, ie->path,
8381 				    a->repo, a->patch_cb, a->patch_arg);
8382 				if (err || path_content == NULL)
8383 					break;
8384 			}
8385 		}
8386 		err = got_object_blob_create(&new_staged_blob_id,
8387 		    path_content ? path_content : ondisk_path, a->repo);
8388 		if (err)
8389 			break;
8390 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
8391 		    SHA1_DIGEST_LENGTH);
8392 		if (status == GOT_STATUS_ADD || staged_status == GOT_STATUS_ADD)
8393 			stage = GOT_FILEIDX_STAGE_ADD;
8394 		else
8395 			stage = GOT_FILEIDX_STAGE_MODIFY;
8396 		got_fileindex_entry_stage_set(ie, stage);
8397 		if (S_ISLNK(sb.st_mode)) {
8398 			int is_bad_symlink = 0;
8399 			if (!a->allow_bad_symlinks) {
8400 				char target_path[PATH_MAX];
8401 				ssize_t target_len;
8402 				target_len = readlink(ondisk_path, target_path,
8403 				    sizeof(target_path));
8404 				if (target_len == -1) {
8405 					err = got_error_from_errno2("readlink",
8406 					    ondisk_path);
8407 					break;
8408 				}
8409 				err = is_bad_symlink_target(&is_bad_symlink,
8410 				    target_path, target_len, ondisk_path,
8411 				    a->worktree->root_path);
8412 				if (err)
8413 					break;
8414 				if (is_bad_symlink) {
8415 					err = got_error_path(ondisk_path,
8416 					    GOT_ERR_BAD_SYMLINK);
8417 					break;
8418 				}
8419 			}
8420 			if (is_bad_symlink)
8421 				got_fileindex_entry_staged_filetype_set(ie,
8422 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
8423 			else
8424 				got_fileindex_entry_staged_filetype_set(ie,
8425 				    GOT_FILEIDX_MODE_SYMLINK);
8426 		} else {
8427 			got_fileindex_entry_staged_filetype_set(ie,
8428 			    GOT_FILEIDX_MODE_REGULAR_FILE);
8429 		}
8430 		a->staged_something = 1;
8431 		if (a->status_cb == NULL)
8432 			break;
8433 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
8434 		    get_staged_status(ie), relpath, blob_id,
8435 		    new_staged_blob_id, NULL, dirfd, de_name);
8436 		if (err)
8437 			break;
8438 		/*
8439 		 * When staging the reverse of the staged diff,
8440 		 * implicitly unstage the file.
8441 		 */
8442 		if (memcmp(ie->staged_blob_sha1, ie->blob_sha1,
8443 		    sizeof(ie->blob_sha1)) == 0) {
8444 			got_fileindex_entry_stage_set(ie,
8445 			    GOT_FILEIDX_STAGE_NONE);
8446 		}
8447 		break;
8448 	case GOT_STATUS_DELETE:
8449 		if (staged_status == GOT_STATUS_DELETE)
8450 			break;
8451 		if (a->patch_cb) {
8452 			int choice = GOT_PATCH_CHOICE_NONE;
8453 			err = (*a->patch_cb)(&choice, a->patch_arg, status,
8454 			    ie->path, NULL, 1, 1);
8455 			if (err)
8456 				break;
8457 			if (choice == GOT_PATCH_CHOICE_NO)
8458 				break;
8459 			if (choice != GOT_PATCH_CHOICE_YES) {
8460 				err = got_error(GOT_ERR_PATCH_CHOICE);
8461 				break;
8462 			}
8463 		}
8464 		stage = GOT_FILEIDX_STAGE_DELETE;
8465 		got_fileindex_entry_stage_set(ie, stage);
8466 		a->staged_something = 1;
8467 		if (a->status_cb == NULL)
8468 			break;
8469 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
8470 		    get_staged_status(ie), relpath, NULL, NULL, NULL, dirfd,
8471 		    de_name);
8472 		break;
8473 	case GOT_STATUS_NO_CHANGE:
8474 		break;
8475 	case GOT_STATUS_CONFLICT:
8476 		err = got_error_path(relpath, GOT_ERR_STAGE_CONFLICT);
8477 		break;
8478 	case GOT_STATUS_NONEXISTENT:
8479 		err = got_error_set_errno(ENOENT, relpath);
8480 		break;
8481 	default:
8482 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
8483 		break;
8484 	}
8485 
8486 	if (path_content && unlink(path_content) == -1 && err == NULL)
8487 		err = got_error_from_errno2("unlink", path_content);
8488 	free(path_content);
8489 	free(ondisk_path);
8490 	free(new_staged_blob_id);
8491 	return err;
8492 }
8493 
8494 const struct got_error *
8495 got_worktree_stage(struct got_worktree *worktree,
8496     struct got_pathlist_head *paths,
8497     got_worktree_status_cb status_cb, void *status_arg,
8498     got_worktree_patch_cb patch_cb, void *patch_arg,
8499     int allow_bad_symlinks, struct got_repository *repo)
8500 {
8501 	const struct got_error *err = NULL, *sync_err, *unlockerr;
8502 	struct got_pathlist_entry *pe;
8503 	struct got_fileindex *fileindex = NULL;
8504 	char *fileindex_path = NULL;
8505 	struct got_reference *head_ref = NULL;
8506 	struct got_object_id *head_commit_id = NULL;
8507 	struct check_stage_ok_arg oka;
8508 	struct stage_path_arg spa;
8509 
8510 	err = lock_worktree(worktree, LOCK_EX);
8511 	if (err)
8512 		return err;
8513 
8514 	err = got_ref_open(&head_ref, repo,
8515 	    got_worktree_get_head_ref_name(worktree), 0);
8516 	if (err)
8517 		goto done;
8518 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
8519 	if (err)
8520 		goto done;
8521 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
8522 	if (err)
8523 		goto done;
8524 
8525 	/* Check pre-conditions before staging anything. */
8526 	oka.head_commit_id = head_commit_id;
8527 	oka.worktree = worktree;
8528 	oka.fileindex = fileindex;
8529 	oka.repo = repo;
8530 	oka.have_changes = 0;
8531 	TAILQ_FOREACH(pe, paths, entry) {
8532 		err = worktree_status(worktree, pe->path, fileindex, repo,
8533 		    check_stage_ok, &oka, NULL, NULL, 1, 0);
8534 		if (err)
8535 			goto done;
8536 	}
8537 	if (!oka.have_changes) {
8538 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
8539 		goto done;
8540 	}
8541 
8542 	spa.worktree = worktree;
8543 	spa.fileindex = fileindex;
8544 	spa.repo = repo;
8545 	spa.patch_cb = patch_cb;
8546 	spa.patch_arg = patch_arg;
8547 	spa.status_cb = status_cb;
8548 	spa.status_arg = status_arg;
8549 	spa.staged_something = 0;
8550 	spa.allow_bad_symlinks = allow_bad_symlinks;
8551 	TAILQ_FOREACH(pe, paths, entry) {
8552 		err = worktree_status(worktree, pe->path, fileindex, repo,
8553 		    stage_path, &spa, NULL, NULL, 1, 0);
8554 		if (err)
8555 			goto done;
8556 	}
8557 	if (!spa.staged_something) {
8558 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
8559 		goto done;
8560 	}
8561 
8562 	sync_err = sync_fileindex(fileindex, fileindex_path);
8563 	if (sync_err && err == NULL)
8564 		err = sync_err;
8565 done:
8566 	if (head_ref)
8567 		got_ref_close(head_ref);
8568 	free(head_commit_id);
8569 	free(fileindex_path);
8570 	if (fileindex)
8571 		got_fileindex_free(fileindex);
8572 	unlockerr = lock_worktree(worktree, LOCK_SH);
8573 	if (unlockerr && err == NULL)
8574 		err = unlockerr;
8575 	return err;
8576 }
8577 
8578 struct unstage_path_arg {
8579 	struct got_worktree *worktree;
8580 	struct got_fileindex *fileindex;
8581 	struct got_repository *repo;
8582 	got_worktree_checkout_cb progress_cb;
8583 	void *progress_arg;
8584 	got_worktree_patch_cb patch_cb;
8585 	void *patch_arg;
8586 };
8587 
8588 static const struct got_error *
8589 create_unstaged_content(char **path_unstaged_content,
8590     char **path_new_staged_content, struct got_object_id *blob_id,
8591     struct got_object_id *staged_blob_id, const char *relpath,
8592     struct got_repository *repo,
8593     got_worktree_patch_cb patch_cb, void *patch_arg)
8594 {
8595 	const struct got_error *err, *free_err;
8596 	struct got_blob_object *blob = NULL, *staged_blob = NULL;
8597 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL, *rejectfile = NULL;
8598 	char *path1 = NULL, *path2 = NULL, *label1 = NULL;
8599 	struct got_diffreg_result *diffreg_result = NULL;
8600 	int line_cur1 = 1, line_cur2 = 1, n = 0, nchunks_used = 0;
8601 	int have_content = 0, have_rejected_content = 0, i = 0, nchanges = 0;
8602 	int fd1 = -1, fd2 = -1;
8603 
8604 	*path_unstaged_content = NULL;
8605 	*path_new_staged_content = NULL;
8606 
8607 	err = got_object_id_str(&label1, blob_id);
8608 	if (err)
8609 		return err;
8610 
8611 	fd1 = got_opentempfd();
8612 	if (fd1 == -1) {
8613 		err = got_error_from_errno("got_opentempfd");
8614 		goto done;
8615 	}
8616 	fd2 = got_opentempfd();
8617 	if (fd2 == -1) {
8618 		err = got_error_from_errno("got_opentempfd");
8619 		goto done;
8620 	}
8621 
8622 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192, fd1);
8623 	if (err)
8624 		goto done;
8625 
8626 	err = got_opentemp_named(&path1, &f1, "got-unstage-blob-base", "");
8627 	if (err)
8628 		goto done;
8629 
8630 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
8631 	if (err)
8632 		goto done;
8633 
8634 	err = got_object_open_as_blob(&staged_blob, repo, staged_blob_id, 8192,
8635 	    fd2);
8636 	if (err)
8637 		goto done;
8638 
8639 	err = got_opentemp_named(&path2, &f2, "got-unstage-blob-staged", "");
8640 	if (err)
8641 		goto done;
8642 
8643 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f2, staged_blob);
8644 	if (err)
8645 		goto done;
8646 
8647 	err = got_diff_files(&diffreg_result, f1, 1, label1, f2, 1,
8648 	    path2, 3, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
8649 	if (err)
8650 		goto done;
8651 
8652 	err = got_opentemp_named(path_unstaged_content, &outfile,
8653 	    "got-unstaged-content", "");
8654 	if (err)
8655 		goto done;
8656 	err = got_opentemp_named(path_new_staged_content, &rejectfile,
8657 	    "got-new-staged-content", "");
8658 	if (err)
8659 		goto done;
8660 
8661 	if (fseek(f1, 0L, SEEK_SET) == -1) {
8662 		err = got_ferror(f1, GOT_ERR_IO);
8663 		goto done;
8664 	}
8665 	if (fseek(f2, 0L, SEEK_SET) == -1) {
8666 		err = got_ferror(f2, GOT_ERR_IO);
8667 		goto done;
8668 	}
8669 	/* Count the number of actual changes in the diff result. */
8670 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
8671 		struct diff_chunk_context cc = {};
8672 		diff_chunk_context_load_change(&cc, &nchunks_used,
8673 		    diffreg_result->result, n, 0);
8674 		nchanges++;
8675 	}
8676 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
8677 		int choice;
8678 		err = apply_or_reject_change(&choice, &nchunks_used,
8679 		    diffreg_result->result, n, relpath, f1, f2,
8680 		    &line_cur1, &line_cur2,
8681 		    outfile, rejectfile, ++i, nchanges, patch_cb, patch_arg);
8682 		if (err)
8683 			goto done;
8684 		if (choice == GOT_PATCH_CHOICE_YES)
8685 			have_content = 1;
8686 		else
8687 			have_rejected_content = 1;
8688 		if (choice == GOT_PATCH_CHOICE_QUIT)
8689 			break;
8690 	}
8691 	if (have_content || have_rejected_content)
8692 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
8693 		    outfile, rejectfile);
8694 done:
8695 	free(label1);
8696 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
8697 		err = got_error_from_errno("close");
8698 	if (blob)
8699 		got_object_blob_close(blob);
8700 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
8701 		err = got_error_from_errno("close");
8702 	if (staged_blob)
8703 		got_object_blob_close(staged_blob);
8704 	free_err = got_diffreg_result_free(diffreg_result);
8705 	if (free_err && err == NULL)
8706 		err = free_err;
8707 	if (f1 && fclose(f1) == EOF && err == NULL)
8708 		err = got_error_from_errno2("fclose", path1);
8709 	if (f2 && fclose(f2) == EOF && err == NULL)
8710 		err = got_error_from_errno2("fclose", path2);
8711 	if (outfile && fclose(outfile) == EOF && err == NULL)
8712 		err = got_error_from_errno2("fclose", *path_unstaged_content);
8713 	if (rejectfile && fclose(rejectfile) == EOF && err == NULL)
8714 		err = got_error_from_errno2("fclose", *path_new_staged_content);
8715 	if (path1 && unlink(path1) == -1 && err == NULL)
8716 		err = got_error_from_errno2("unlink", path1);
8717 	if (path2 && unlink(path2) == -1 && err == NULL)
8718 		err = got_error_from_errno2("unlink", path2);
8719 	if (err || !have_content) {
8720 		if (*path_unstaged_content &&
8721 		    unlink(*path_unstaged_content) == -1 && err == NULL)
8722 			err = got_error_from_errno2("unlink",
8723 			    *path_unstaged_content);
8724 		free(*path_unstaged_content);
8725 		*path_unstaged_content = NULL;
8726 	}
8727 	if (err || !have_content || !have_rejected_content) {
8728 		if (*path_new_staged_content &&
8729 		    unlink(*path_new_staged_content) == -1 && err == NULL)
8730 			err = got_error_from_errno2("unlink",
8731 			    *path_new_staged_content);
8732 		free(*path_new_staged_content);
8733 		*path_new_staged_content = NULL;
8734 	}
8735 	free(path1);
8736 	free(path2);
8737 	return err;
8738 }
8739 
8740 static const struct got_error *
8741 unstage_hunks(struct got_object_id *staged_blob_id,
8742     struct got_blob_object *blob_base,
8743     struct got_object_id *blob_id, struct got_fileindex_entry *ie,
8744     const char *ondisk_path, const char *label_orig,
8745     struct got_worktree *worktree, struct got_repository *repo,
8746     got_worktree_patch_cb patch_cb, void *patch_arg,
8747     got_worktree_checkout_cb progress_cb, void *progress_arg)
8748 {
8749 	const struct got_error *err = NULL;
8750 	char *path_unstaged_content = NULL;
8751 	char *path_new_staged_content = NULL;
8752 	char *parent = NULL, *base_path = NULL;
8753 	char *blob_base_path = NULL;
8754 	struct got_object_id *new_staged_blob_id = NULL;
8755 	FILE *f = NULL, *f_base = NULL, *f_deriv2 = NULL;
8756 	struct stat sb;
8757 
8758 	err = create_unstaged_content(&path_unstaged_content,
8759 	    &path_new_staged_content, blob_id, staged_blob_id,
8760 	    ie->path, repo, patch_cb, patch_arg);
8761 	if (err)
8762 		return err;
8763 
8764 	if (path_unstaged_content == NULL)
8765 		return NULL;
8766 
8767 	if (path_new_staged_content) {
8768 		err = got_object_blob_create(&new_staged_blob_id,
8769 		    path_new_staged_content, repo);
8770 		if (err)
8771 			goto done;
8772 	}
8773 
8774 	f = fopen(path_unstaged_content, "re");
8775 	if (f == NULL) {
8776 		err = got_error_from_errno2("fopen",
8777 		    path_unstaged_content);
8778 		goto done;
8779 	}
8780 	if (fstat(fileno(f), &sb) == -1) {
8781 		err = got_error_from_errno2("fstat", path_unstaged_content);
8782 		goto done;
8783 	}
8784 	if (got_fileindex_entry_staged_filetype_get(ie) ==
8785 	    GOT_FILEIDX_MODE_SYMLINK && sb.st_size < PATH_MAX) {
8786 		char link_target[PATH_MAX];
8787 		size_t r;
8788 		r = fread(link_target, 1, sizeof(link_target), f);
8789 		if (r == 0 && ferror(f)) {
8790 			err = got_error_from_errno("fread");
8791 			goto done;
8792 		}
8793 		if (r >= sizeof(link_target)) { /* should not happen */
8794 			err = got_error(GOT_ERR_NO_SPACE);
8795 			goto done;
8796 		}
8797 		link_target[r] = '\0';
8798 		err = merge_symlink(worktree, blob_base,
8799 		    ondisk_path, ie->path, label_orig, link_target,
8800 		    worktree->base_commit_id, repo, progress_cb,
8801 		    progress_arg);
8802 	} else {
8803 		int local_changes_subsumed;
8804 
8805 		err = got_path_dirname(&parent, ondisk_path);
8806 		if (err)
8807 			return err;
8808 
8809 		if (asprintf(&base_path, "%s/got-unstage-blob-orig",
8810 		    parent) == -1) {
8811 			err = got_error_from_errno("asprintf");
8812 			base_path = NULL;
8813 			goto done;
8814 		}
8815 
8816 		err = got_opentemp_named(&blob_base_path, &f_base,
8817 		    base_path, "");
8818 		if (err)
8819 			goto done;
8820 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_base,
8821 		    blob_base);
8822 		if (err)
8823 			goto done;
8824 
8825 		/*
8826 		 * In order the run a 3-way merge with a symlink we copy the symlink's
8827 		 * target path into a temporary file and use that file with diff3.
8828 		 */
8829 		if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
8830 			err = dump_symlink_target_path_to_file(&f_deriv2,
8831 			    ondisk_path);
8832 			if (err)
8833 				goto done;
8834 		} else {
8835 			int fd;
8836 			fd = open(ondisk_path,
8837 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
8838 			if (fd == -1) {
8839 				err = got_error_from_errno2("open", ondisk_path);
8840 				goto done;
8841 			}
8842 			f_deriv2 = fdopen(fd, "r");
8843 			if (f_deriv2 == NULL) {
8844 				err = got_error_from_errno2("fdopen", ondisk_path);
8845 				close(fd);
8846 				goto done;
8847 			}
8848 		}
8849 
8850 		err = merge_file(&local_changes_subsumed, worktree,
8851 		    f_base, f, f_deriv2, ondisk_path, ie->path,
8852 		    got_fileindex_perms_to_st(ie),
8853 		    label_orig, "unstaged", NULL, GOT_DIFF_ALGORITHM_MYERS,
8854 		    repo, progress_cb, progress_arg);
8855 	}
8856 	if (err)
8857 		goto done;
8858 
8859 	if (new_staged_blob_id) {
8860 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
8861 		    SHA1_DIGEST_LENGTH);
8862 	} else {
8863 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
8864 		got_fileindex_entry_staged_filetype_set(ie, 0);
8865 	}
8866 done:
8867 	free(new_staged_blob_id);
8868 	if (path_unstaged_content &&
8869 	    unlink(path_unstaged_content) == -1 && err == NULL)
8870 		err = got_error_from_errno2("unlink", path_unstaged_content);
8871 	if (path_new_staged_content &&
8872 	    unlink(path_new_staged_content) == -1 && err == NULL)
8873 		err = got_error_from_errno2("unlink", path_new_staged_content);
8874 	if (blob_base_path && unlink(blob_base_path) == -1 && err == NULL)
8875 		err = got_error_from_errno2("unlink", blob_base_path);
8876 	if (f_base && fclose(f_base) == EOF && err == NULL)
8877 		err = got_error_from_errno2("fclose", path_unstaged_content);
8878 	if (f && fclose(f) == EOF && err == NULL)
8879 		err = got_error_from_errno2("fclose", path_unstaged_content);
8880 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
8881 		err = got_error_from_errno2("fclose", ondisk_path);
8882 	free(path_unstaged_content);
8883 	free(path_new_staged_content);
8884 	free(blob_base_path);
8885 	free(parent);
8886 	free(base_path);
8887 	return err;
8888 }
8889 
8890 static const struct got_error *
8891 unstage_path(void *arg, unsigned char status,
8892     unsigned char staged_status, const char *relpath,
8893     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8894     struct got_object_id *commit_id, int dirfd, const char *de_name)
8895 {
8896 	const struct got_error *err = NULL;
8897 	struct unstage_path_arg *a = arg;
8898 	struct got_fileindex_entry *ie;
8899 	struct got_blob_object *blob_base = NULL, *blob_staged = NULL;
8900 	char *ondisk_path = NULL;
8901 	char *id_str = NULL, *label_orig = NULL;
8902 	int local_changes_subsumed;
8903 	struct stat sb;
8904 	int fd1 = -1, fd2 = -1;
8905 
8906 	if (staged_status != GOT_STATUS_ADD &&
8907 	    staged_status != GOT_STATUS_MODIFY &&
8908 	    staged_status != GOT_STATUS_DELETE)
8909 		return NULL;
8910 
8911 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8912 	if (ie == NULL)
8913 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8914 
8915 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, relpath)
8916 	    == -1)
8917 		return got_error_from_errno("asprintf");
8918 
8919 	err = got_object_id_str(&id_str,
8920 	    commit_id ? commit_id : a->worktree->base_commit_id);
8921 	if (err)
8922 		goto done;
8923 	if (asprintf(&label_orig, "%s: commit %s", GOT_MERGE_LABEL_BASE,
8924 	    id_str) == -1) {
8925 		err = got_error_from_errno("asprintf");
8926 		goto done;
8927 	}
8928 
8929 	fd1 = got_opentempfd();
8930 	if (fd1 == -1) {
8931 		err = got_error_from_errno("got_opentempfd");
8932 		goto done;
8933 	}
8934 	fd2 = got_opentempfd();
8935 	if (fd2 == -1) {
8936 		err = got_error_from_errno("got_opentempfd");
8937 		goto done;
8938 	}
8939 
8940 	switch (staged_status) {
8941 	case GOT_STATUS_MODIFY:
8942 		err = got_object_open_as_blob(&blob_base, a->repo,
8943 		    blob_id, 8192, fd1);
8944 		if (err)
8945 			break;
8946 		/* fall through */
8947 	case GOT_STATUS_ADD:
8948 		if (a->patch_cb) {
8949 			if (staged_status == GOT_STATUS_ADD) {
8950 				int choice = GOT_PATCH_CHOICE_NONE;
8951 				err = (*a->patch_cb)(&choice, a->patch_arg,
8952 				    staged_status, ie->path, NULL, 1, 1);
8953 				if (err)
8954 					break;
8955 				if (choice != GOT_PATCH_CHOICE_YES)
8956 					break;
8957 			} else {
8958 				err = unstage_hunks(staged_blob_id,
8959 				    blob_base, blob_id, ie, ondisk_path,
8960 				    label_orig, a->worktree, a->repo,
8961 				    a->patch_cb, a->patch_arg,
8962 				    a->progress_cb, a->progress_arg);
8963 				break; /* Done with this file. */
8964 			}
8965 		}
8966 		err = got_object_open_as_blob(&blob_staged, a->repo,
8967 		    staged_blob_id, 8192, fd2);
8968 		if (err)
8969 			break;
8970 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
8971 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
8972 		case GOT_FILEIDX_MODE_REGULAR_FILE:
8973 			err = merge_blob(&local_changes_subsumed, a->worktree,
8974 			    blob_base, ondisk_path, relpath,
8975 			    got_fileindex_perms_to_st(ie), label_orig,
8976 			    blob_staged, commit_id ? commit_id :
8977 			    a->worktree->base_commit_id, a->repo,
8978 			    a->progress_cb, a->progress_arg);
8979 			break;
8980 		case GOT_FILEIDX_MODE_SYMLINK:
8981 			if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
8982 				char *staged_target;
8983 				err = got_object_blob_read_to_str(
8984 				    &staged_target, blob_staged);
8985 				if (err)
8986 					goto done;
8987 				err = merge_symlink(a->worktree, blob_base,
8988 				    ondisk_path, relpath, label_orig,
8989 				    staged_target, commit_id ? commit_id :
8990 				    a->worktree->base_commit_id,
8991 				    a->repo, a->progress_cb, a->progress_arg);
8992 				free(staged_target);
8993 			} else {
8994 				err = merge_blob(&local_changes_subsumed,
8995 				    a->worktree, blob_base, ondisk_path,
8996 				    relpath, got_fileindex_perms_to_st(ie),
8997 				    label_orig, blob_staged,
8998 				    commit_id ? commit_id :
8999 				    a->worktree->base_commit_id, a->repo,
9000 				    a->progress_cb, a->progress_arg);
9001 			}
9002 			break;
9003 		default:
9004 			err = got_error_path(relpath, GOT_ERR_BAD_FILETYPE);
9005 			break;
9006 		}
9007 		if (err == NULL) {
9008 			got_fileindex_entry_stage_set(ie,
9009 			    GOT_FILEIDX_STAGE_NONE);
9010 			got_fileindex_entry_staged_filetype_set(ie, 0);
9011 		}
9012 		break;
9013 	case GOT_STATUS_DELETE:
9014 		if (a->patch_cb) {
9015 			int choice = GOT_PATCH_CHOICE_NONE;
9016 			err = (*a->patch_cb)(&choice, a->patch_arg,
9017 			    staged_status, ie->path, NULL, 1, 1);
9018 			if (err)
9019 				break;
9020 			if (choice == GOT_PATCH_CHOICE_NO)
9021 				break;
9022 			if (choice != GOT_PATCH_CHOICE_YES) {
9023 				err = got_error(GOT_ERR_PATCH_CHOICE);
9024 				break;
9025 			}
9026 		}
9027 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
9028 		got_fileindex_entry_staged_filetype_set(ie, 0);
9029 		err = get_file_status(&status, &sb, ie, ondisk_path,
9030 		    dirfd, de_name, a->repo);
9031 		if (err)
9032 			break;
9033 		err = (*a->progress_cb)(a->progress_arg, status, relpath);
9034 		break;
9035 	}
9036 done:
9037 	free(ondisk_path);
9038 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
9039 		err = got_error_from_errno("close");
9040 	if (blob_base)
9041 		got_object_blob_close(blob_base);
9042 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
9043 		err = got_error_from_errno("close");
9044 	if (blob_staged)
9045 		got_object_blob_close(blob_staged);
9046 	free(id_str);
9047 	free(label_orig);
9048 	return err;
9049 }
9050 
9051 const struct got_error *
9052 got_worktree_unstage(struct got_worktree *worktree,
9053     struct got_pathlist_head *paths,
9054     got_worktree_checkout_cb progress_cb, void *progress_arg,
9055     got_worktree_patch_cb patch_cb, void *patch_arg,
9056     struct got_repository *repo)
9057 {
9058 	const struct got_error *err = NULL, *sync_err, *unlockerr;
9059 	struct got_pathlist_entry *pe;
9060 	struct got_fileindex *fileindex = NULL;
9061 	char *fileindex_path = NULL;
9062 	struct unstage_path_arg upa;
9063 
9064 	err = lock_worktree(worktree, LOCK_EX);
9065 	if (err)
9066 		return err;
9067 
9068 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
9069 	if (err)
9070 		goto done;
9071 
9072 	upa.worktree = worktree;
9073 	upa.fileindex = fileindex;
9074 	upa.repo = repo;
9075 	upa.progress_cb = progress_cb;
9076 	upa.progress_arg = progress_arg;
9077 	upa.patch_cb = patch_cb;
9078 	upa.patch_arg = patch_arg;
9079 	TAILQ_FOREACH(pe, paths, entry) {
9080 		err = worktree_status(worktree, pe->path, fileindex, repo,
9081 		    unstage_path, &upa, NULL, NULL, 1, 0);
9082 		if (err)
9083 			goto done;
9084 	}
9085 
9086 	sync_err = sync_fileindex(fileindex, fileindex_path);
9087 	if (sync_err && err == NULL)
9088 		err = sync_err;
9089 done:
9090 	free(fileindex_path);
9091 	if (fileindex)
9092 		got_fileindex_free(fileindex);
9093 	unlockerr = lock_worktree(worktree, LOCK_SH);
9094 	if (unlockerr && err == NULL)
9095 		err = unlockerr;
9096 	return err;
9097 }
9098 
9099 struct report_file_info_arg {
9100 	struct got_worktree *worktree;
9101 	got_worktree_path_info_cb info_cb;
9102 	void *info_arg;
9103 	struct got_pathlist_head *paths;
9104 	got_cancel_cb cancel_cb;
9105 	void *cancel_arg;
9106 };
9107 
9108 static const struct got_error *
9109 report_file_info(void *arg, struct got_fileindex_entry *ie)
9110 {
9111 	struct report_file_info_arg *a = arg;
9112 	struct got_pathlist_entry *pe;
9113 	struct got_object_id blob_id, staged_blob_id, commit_id;
9114 	struct got_object_id *blob_idp = NULL, *staged_blob_idp = NULL;
9115 	struct got_object_id *commit_idp = NULL;
9116 	int stage;
9117 
9118 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
9119 		return got_error(GOT_ERR_CANCELLED);
9120 
9121 	TAILQ_FOREACH(pe, a->paths, entry) {
9122 		if (pe->path_len == 0 || strcmp(pe->path, ie->path) == 0 ||
9123 		    got_path_is_child(ie->path, pe->path, pe->path_len))
9124 			break;
9125 	}
9126 	if (pe == NULL) /* not found */
9127 		return NULL;
9128 
9129 	if (got_fileindex_entry_has_blob(ie)) {
9130 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
9131 		blob_idp = &blob_id;
9132 	}
9133 	stage = got_fileindex_entry_stage_get(ie);
9134 	if (stage == GOT_FILEIDX_STAGE_MODIFY ||
9135 	    stage == GOT_FILEIDX_STAGE_ADD) {
9136 		memcpy(staged_blob_id.sha1, ie->staged_blob_sha1,
9137 		    SHA1_DIGEST_LENGTH);
9138 		staged_blob_idp = &staged_blob_id;
9139 	}
9140 
9141 	if (got_fileindex_entry_has_commit(ie)) {
9142 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
9143 		commit_idp = &commit_id;
9144 	}
9145 
9146 	return a->info_cb(a->info_arg, ie->path, got_fileindex_perms_to_st(ie),
9147 	    (time_t)ie->mtime_sec, blob_idp, staged_blob_idp, commit_idp);
9148 }
9149 
9150 const struct got_error *
9151 got_worktree_path_info(struct got_worktree *worktree,
9152     struct got_pathlist_head *paths,
9153     got_worktree_path_info_cb info_cb, void *info_arg,
9154     got_cancel_cb cancel_cb, void *cancel_arg)
9155 
9156 {
9157 	const struct got_error *err = NULL, *unlockerr;
9158 	struct got_fileindex *fileindex = NULL;
9159 	char *fileindex_path = NULL;
9160 	struct report_file_info_arg arg;
9161 
9162 	err = lock_worktree(worktree, LOCK_SH);
9163 	if (err)
9164 		return err;
9165 
9166 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
9167 	if (err)
9168 		goto done;
9169 
9170 	arg.worktree = worktree;
9171 	arg.info_cb = info_cb;
9172 	arg.info_arg = info_arg;
9173 	arg.paths = paths;
9174 	arg.cancel_cb = cancel_cb;
9175 	arg.cancel_arg = cancel_arg;
9176 	err = got_fileindex_for_each_entry_safe(fileindex, report_file_info,
9177 	    &arg);
9178 done:
9179 	free(fileindex_path);
9180 	if (fileindex)
9181 		got_fileindex_free(fileindex);
9182 	unlockerr = lock_worktree(worktree, LOCK_UN);
9183 	if (unlockerr && err == NULL)
9184 		err = unlockerr;
9185 	return err;
9186 }
9187 
9188 static const struct got_error *
9189 patch_check_path(const char *p, char **path, unsigned char *status,
9190     unsigned char *staged_status, struct got_fileindex *fileindex,
9191     struct got_worktree *worktree, struct got_repository *repo)
9192 {
9193 	const struct got_error *err;
9194 	struct got_fileindex_entry *ie;
9195 	struct stat sb;
9196 	char *ondisk_path = NULL;
9197 
9198 	err = got_worktree_resolve_path(path, worktree, p);
9199 	if (err)
9200 		return err;
9201 
9202 	if (asprintf(&ondisk_path, "%s%s%s", worktree->root_path,
9203 	    *path[0] ? "/" : "", *path) == -1)
9204 		return got_error_from_errno("asprintf");
9205 
9206 	ie = got_fileindex_entry_get(fileindex, *path, strlen(*path));
9207 	if (ie) {
9208 		*staged_status = get_staged_status(ie);
9209 		err = get_file_status(status, &sb, ie, ondisk_path, -1, NULL,
9210 		    repo);
9211 		if (err)
9212 			goto done;
9213 	} else {
9214 		*staged_status = GOT_STATUS_NO_CHANGE;
9215 		*status = GOT_STATUS_UNVERSIONED;
9216 		if (lstat(ondisk_path, &sb) == -1) {
9217 			if (errno != ENOENT) {
9218 				err = got_error_from_errno2("lstat",
9219 				    ondisk_path);
9220 				goto done;
9221 			}
9222 			*status = GOT_STATUS_NONEXISTENT;
9223 		}
9224 	}
9225 
9226 done:
9227 	free(ondisk_path);
9228 	return err;
9229 }
9230 
9231 static const struct got_error *
9232 patch_can_rm(const char *path, unsigned char status,
9233     unsigned char staged_status)
9234 {
9235 	if (status == GOT_STATUS_NONEXISTENT)
9236 		return got_error_set_errno(ENOENT, path);
9237 	if (status != GOT_STATUS_NO_CHANGE &&
9238 	    status != GOT_STATUS_ADD &&
9239 	    status != GOT_STATUS_MODIFY &&
9240 	    status != GOT_STATUS_MODE_CHANGE)
9241 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9242 	if (staged_status == GOT_STATUS_DELETE)
9243 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9244 	return NULL;
9245 }
9246 
9247 static const struct got_error *
9248 patch_can_add(const char *path, unsigned char status)
9249 {
9250 	if (status != GOT_STATUS_NONEXISTENT)
9251 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9252 	return NULL;
9253 }
9254 
9255 static const struct got_error *
9256 patch_can_edit(const char *path, unsigned char status,
9257     unsigned char staged_status)
9258 {
9259 	if (status == GOT_STATUS_NONEXISTENT)
9260 		return got_error_set_errno(ENOENT, path);
9261 	if (status != GOT_STATUS_NO_CHANGE &&
9262 	    status != GOT_STATUS_ADD &&
9263 	    status != GOT_STATUS_MODIFY)
9264 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9265 	if (staged_status == GOT_STATUS_DELETE)
9266 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9267 	return NULL;
9268 }
9269 
9270 const struct got_error *
9271 got_worktree_patch_prepare(struct got_fileindex **fileindex,
9272     char **fileindex_path, struct got_worktree *worktree)
9273 {
9274 	return open_fileindex(fileindex, fileindex_path, worktree);
9275 }
9276 
9277 const struct got_error *
9278 got_worktree_patch_check_path(const char *old, const char *new,
9279     char **oldpath, char **newpath, struct got_worktree *worktree,
9280     struct got_repository *repo, struct got_fileindex *fileindex)
9281 {
9282 	const struct got_error *err = NULL;
9283 	int file_renamed = 0;
9284 	unsigned char status_old, staged_status_old;
9285 	unsigned char status_new, staged_status_new;
9286 
9287 	*oldpath = NULL;
9288 	*newpath = NULL;
9289 
9290 	err = patch_check_path(old != NULL ? old : new, oldpath,
9291 	    &status_old, &staged_status_old, fileindex, worktree, repo);
9292 	if (err)
9293 		goto done;
9294 
9295 	err = patch_check_path(new != NULL ? new : old, newpath,
9296 	    &status_new, &staged_status_new, fileindex, worktree, repo);
9297 	if (err)
9298 		goto done;
9299 
9300 	if (old != NULL && new != NULL && strcmp(old, new) != 0)
9301 		file_renamed = 1;
9302 
9303 	if (old != NULL && new == NULL)
9304 		err = patch_can_rm(*oldpath, status_old, staged_status_old);
9305 	else if (file_renamed) {
9306 		err = patch_can_rm(*oldpath, status_old, staged_status_old);
9307 		if (err == NULL)
9308 			err = patch_can_add(*newpath, status_new);
9309 	} else if (old == NULL)
9310 		err = patch_can_add(*newpath, status_new);
9311 	else
9312 		err = patch_can_edit(*newpath, status_new, staged_status_new);
9313 
9314 done:
9315 	if (err) {
9316 		free(*oldpath);
9317 		*oldpath = NULL;
9318 		free(*newpath);
9319 		*newpath = NULL;
9320 	}
9321 	return err;
9322 }
9323 
9324 const struct got_error *
9325 got_worktree_patch_schedule_add(const char *path, struct got_repository *repo,
9326     struct got_worktree *worktree, struct got_fileindex *fileindex,
9327     got_worktree_checkout_cb progress_cb, void *progress_arg)
9328 {
9329 	struct schedule_addition_args saa;
9330 
9331 	memset(&saa, 0, sizeof(saa));
9332 	saa.worktree = worktree;
9333 	saa.fileindex = fileindex;
9334 	saa.progress_cb = progress_cb;
9335 	saa.progress_arg = progress_arg;
9336 	saa.repo = repo;
9337 
9338 	return worktree_status(worktree, path, fileindex, repo,
9339 	    schedule_addition, &saa, NULL, NULL, 1, 0);
9340 }
9341 
9342 const struct got_error *
9343 got_worktree_patch_schedule_rm(const char *path, struct got_repository *repo,
9344     struct got_worktree *worktree, struct got_fileindex *fileindex,
9345     got_worktree_delete_cb progress_cb, void *progress_arg)
9346 {
9347 	struct schedule_deletion_args sda;
9348 
9349 	memset(&sda, 0, sizeof(sda));
9350 	sda.worktree = worktree;
9351 	sda.fileindex = fileindex;
9352 	sda.progress_cb = progress_cb;
9353 	sda.progress_arg = progress_arg;
9354 	sda.repo = repo;
9355 	sda.delete_local_mods = 0;
9356 	sda.keep_on_disk = 0;
9357 	sda.ignore_missing_paths = 0;
9358 	sda.status_codes = NULL;
9359 
9360 	return worktree_status(worktree, path, fileindex, repo,
9361 	    schedule_for_deletion, &sda, NULL, NULL, 1, 1);
9362 }
9363 
9364 const struct got_error *
9365 got_worktree_patch_complete(struct got_fileindex *fileindex,
9366     const char *fileindex_path)
9367 {
9368 	const struct got_error *err = NULL;
9369 
9370 	err = sync_fileindex(fileindex, fileindex_path);
9371 	got_fileindex_free(fileindex);
9372 
9373 	return err;
9374 }