Game of Trees Repos

Blob

Date:: Tue Apr 23 07:49:08 2024 UTC
Message:: got patch: fix applying on empty files if we've reached EOF without finding a match is fine if and only if the target file is empty, so add this exception. reported by naddy, ok stsp
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1 /*
2  * Copyright (c) 2022 Omar Polo <op@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  * Apply patches.
17  *
18  * Things that we may want to support:
19  *     + support indented patches?
20  *     + support other kinds of patches?
21  */
22 
23 #include <sys/types.h>
24 #include <sys/queue.h>
25 #include <sys/socket.h>
26 #include <sys/stat.h>
27 #include <sys/uio.h>
28 
29 #include <ctype.h>
30 #include <errno.h>
31 #include <limits.h>
32 #include <sha1.h>
33 #include <sha2.h>
34 #include <stdint.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 #include <imsg.h>
40 
41 #include "got_error.h"
42 #include "got_object.h"
43 #include "got_path.h"
44 #include "got_reference.h"
45 #include "got_cancel.h"
46 #include "got_worktree.h"
47 #include "got_repository.h"
48 #include "got_opentemp.h"
49 #include "got_patch.h"
50 #include "got_diff.h"
51 
52 #include "got_lib_delta.h"
53 #include "got_lib_diff.h"
54 #include "got_lib_object.h"
55 #include "got_lib_privsep.h"
56 #include "got_lib_hash.h"
57 
58 #ifndef MIN
59 #define MIN(a, b) ((a) < (b) ? (a) : (b))
60 #endif
61 
62 struct got_patch_line {
63 	char	 mode;
64 	char	*line;
65 	size_t	 len;
66 };
67 
68 struct got_patch_hunk {
69 	STAILQ_ENTRY(got_patch_hunk) entries;
70 	const struct got_error *err;
71 	int	ws_mangled;
72 	int	offset;
73 	int	old_nonl;
74 	int	new_nonl;
75 	int	old_from;
76 	int	old_lines;
77 	int	new_from;
78 	int	new_lines;
79 	size_t	len;
80 	size_t	cap;
81 	struct got_patch_line *lines;
82 };
83 
84 STAILQ_HEAD(got_patch_hunk_head, got_patch_hunk);
85 struct got_patch {
86 	int	 xbit;
87 	char	*old;
88 	char	*new;
89 	char	 cid[41];
90 	char	 blob[41];
91 	struct got_patch_hunk_head head;
92 };
93 
94 struct patch_args {
95 	got_patch_progress_cb progress_cb;
96 	void	*progress_arg;
97 	struct got_patch_hunk_head *head;
98 };
99 
100 static mode_t
101 apply_umask(mode_t mode)
102 {
103 	mode_t um;
104 
105 	um = umask(000);
106 	umask(um);
107 	return mode & ~um;
108 }
109 
110 static const struct got_error *
111 send_patch(struct imsgbuf *ibuf, int fd)
112 {
113 	const struct got_error *err = NULL;
114 
115 	if (imsg_compose(ibuf, GOT_IMSG_PATCH_FILE, 0, 0, fd,
116 	    NULL, 0) == -1) {
117 		err = got_error_from_errno(
118 		    "imsg_compose GOT_IMSG_PATCH_FILE");
119 		close(fd);
120 		return err;
121 	}
122 
123 	return got_privsep_flush_imsg(ibuf);
124 }
125 
126 static void
127 patch_free(struct got_patch *p)
128 {
129 	struct got_patch_hunk *h;
130 	size_t i;
131 
132 	while (!STAILQ_EMPTY(&p->head)) {
133 		h = STAILQ_FIRST(&p->head);
134 		STAILQ_REMOVE_HEAD(&p->head, entries);
135 
136 		for (i = 0; i < h->len; ++i)
137 			free(h->lines[i].line);
138 		free(h->lines);
139 		free(h);
140 	}
141 
142 	free(p->new);
143 	free(p->old);
144 
145 	memset(p, 0, sizeof(*p));
146 	STAILQ_INIT(&p->head);
147 }
148 
149 static const struct got_error *
150 pushline(struct got_patch_hunk *h, const char *line, size_t len)
151 {
152 	void 	*t;
153 	size_t	 newcap;
154 
155 	if (h->len == h->cap) {
156 		if ((newcap = h->cap * 1.5) == 0)
157 			newcap = 16;
158 		t = recallocarray(h->lines, h->cap, newcap,
159 		    sizeof(h->lines[0]));
160 		if (t == NULL)
161 			return got_error_from_errno("recallocarray");
162 		h->lines = t;
163 		h->cap = newcap;
164 	}
165 
166 	if ((t = malloc(len - 1)) == NULL)
167 		return got_error_from_errno("malloc");
168 	memcpy(t, line + 1, len - 1);	/* skip the line type */
169 
170 	h->lines[h->len].mode = *line;
171 	h->lines[h->len].line = t;
172 	h->lines[h->len].len = len - 2;	/* line type and trailing NUL */
173 	h->len++;
174 	return NULL;
175 }
176 
177 static const struct got_error *
178 recv_patch(struct imsgbuf *ibuf, int *done, struct got_patch *p, int strip)
179 {
180 	const struct got_error *err = NULL;
181 	struct imsg imsg;
182 	struct got_imsg_patch_hunk hdr;
183 	struct got_imsg_patch patch;
184 	struct got_patch_hunk *h = NULL;
185 	size_t datalen;
186 	int lastmode = -1;
187 
188 	memset(p, 0, sizeof(*p));
189 	STAILQ_INIT(&p->head);
190 
191 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
192 	if (err)
193 		return err;
194 	if (imsg.hdr.type == GOT_IMSG_PATCH_EOF) {
195 		*done = 1;
196 		goto done;
197 	}
198 	if (imsg.hdr.type != GOT_IMSG_PATCH) {
199 		err = got_error(GOT_ERR_PRIVSEP_MSG);
200 		goto done;
201 	}
202 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
203 	if (datalen != sizeof(patch)) {
204 		err = got_error(GOT_ERR_PRIVSEP_LEN);
205 		goto done;
206 	}
207 	memcpy(&patch, imsg.data, sizeof(patch));
208 
209 	if (patch.old[sizeof(patch.old)-1] != '\0' ||
210 	    patch.new[sizeof(patch.new)-1] != '\0' ||
211 	    patch.cid[sizeof(patch.cid)-1] != '\0' ||
212 	    patch.blob[sizeof(patch.blob)-1] != '\0') {
213 		err = got_error(GOT_ERR_PRIVSEP_LEN);
214 		goto done;
215 	}
216 
217 	if (*patch.cid != '\0')
218 		strlcpy(p->cid, patch.cid, sizeof(p->cid));
219 
220 	if (*patch.blob != '\0')
221 		strlcpy(p->blob, patch.blob, sizeof(p->blob));
222 
223 	p->xbit = patch.xbit;
224 
225 	/* automatically set strip=1 for git-style diffs */
226 	if (strip == -1 && patch.git &&
227 	    (*patch.old == '\0' || !strncmp(patch.old, "a/", 2)) &&
228 	    (*patch.new == '\0' || !strncmp(patch.new, "b/", 2)))
229 		strip = 1;
230 
231 	/* prefer the new name if not /dev/null for not git-style diffs */
232 	if (!patch.git && *patch.new != '\0' && *patch.old != '\0') {
233 		err = got_path_strip(&p->old, patch.new, strip);
234 		if (err)
235 			goto done;
236 	} else if (*patch.old != '\0') {
237 		err = got_path_strip(&p->old, patch.old, strip);
238 		if (err)
239 			goto done;
240 	}
241 
242 	if (*patch.new != '\0') {
243 		err = got_path_strip(&p->new, patch.new, strip);
244 		if (err)
245 			goto done;
246 	}
247 
248 	if (p->old == NULL && p->new == NULL) {
249 		err = got_error(GOT_ERR_PATCH_MALFORMED);
250 		goto done;
251 	}
252 
253 	imsg_free(&imsg);
254 
255 	for (;;) {
256 		char *t;
257 
258 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
259 		if (err) {
260 			patch_free(p);
261 			return err;
262 		}
263 
264 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
265 		switch (imsg.hdr.type) {
266 		case GOT_IMSG_PATCH_DONE:
267 			if (h != NULL && h->len == 0)
268 				err = got_error(GOT_ERR_PATCH_MALFORMED);
269 			goto done;
270 		case GOT_IMSG_PATCH_HUNK:
271 			if (h != NULL &&
272 			    (h->len == 0 || h->old_nonl || h->new_nonl)) {
273 				err = got_error(GOT_ERR_PATCH_MALFORMED);
274 				goto done;
275 			}
276 			lastmode = -1;
277 			if (datalen != sizeof(hdr)) {
278 				err = got_error(GOT_ERR_PRIVSEP_LEN);
279 				goto done;
280 			}
281 			memcpy(&hdr, imsg.data, sizeof(hdr));
282 			if (hdr.oldfrom < 0 || hdr.newfrom < 0) {
283 				err = got_error(GOT_ERR_PRIVSEP_LEN);
284 				goto done;
285 			}
286 			if ((h = calloc(1, sizeof(*h))) == NULL) {
287 				err = got_error_from_errno("calloc");
288 				goto done;
289 			}
290 			h->old_from = hdr.oldfrom;
291 			h->old_lines = hdr.oldlines;
292 			h->new_from = hdr.newfrom;
293 			h->new_lines = hdr.newlines;
294 			STAILQ_INSERT_TAIL(&p->head, h, entries);
295 			break;
296 		case GOT_IMSG_PATCH_LINE:
297 			if (h == NULL) {
298 				err = got_error(GOT_ERR_PRIVSEP_MSG);
299 				goto done;
300 			}
301 			t = imsg.data;
302 			/* at least one char */
303 			if (datalen < 2 || t[datalen-1] != '\0') {
304 				err = got_error(GOT_ERR_PRIVSEP_MSG);
305 				goto done;
306 			}
307 			if (*t != ' ' && *t != '-' && *t != '+' &&
308 			    *t != '\\') {
309 				err = got_error(GOT_ERR_PRIVSEP_MSG);
310 				goto done;
311 			}
312 
313 			if (*t != '\\')
314 				err = pushline(h, t, datalen);
315 			else if (lastmode == '-')
316 				h->old_nonl = 1;
317 			else if (lastmode == '+')
318 				h->new_nonl = 1;
319 			else
320 				err = got_error(GOT_ERR_PATCH_MALFORMED);
321 
322 			if (err)
323 				goto done;
324 
325 			lastmode = *t;
326 			break;
327 		default:
328 			err = got_error(GOT_ERR_PRIVSEP_MSG);
329 			goto done;
330 		}
331 
332 		imsg_free(&imsg);
333 	}
334 
335 done:
336 	if (err)
337 		patch_free(p);
338 
339 	imsg_free(&imsg);
340 	return err;
341 }
342 
343 static void
344 reverse_patch(struct got_patch *p)
345 {
346 	struct got_patch_hunk *h;
347 	size_t i;
348 	int tmp;
349 
350 	STAILQ_FOREACH(h, &p->head, entries) {
351 		tmp = h->old_from;
352 		h->old_from = h->new_from;
353 		h->new_from = tmp;
354 
355 		tmp = h->old_lines;
356 		h->old_lines = h->new_lines;
357 		h->new_lines = tmp;
358 
359 		tmp = h->old_nonl;
360 		h->old_nonl = h->new_nonl;
361 		h->new_nonl = tmp;
362 
363 		for (i = 0; i < h->len; ++i) {
364 			if (h->lines[i].mode == '+')
365 				h->lines[i].mode = '-';
366 			else if (h->lines[i].mode == '-')
367 				h->lines[i].mode = '+';
368 		}
369 	}
370 }
371 
372 /*
373  * Copy data from orig starting at copypos until pos into tmp.
374  * If pos is -1, copy until EOF.
375  */
376 static const struct got_error *
377 copy(FILE *tmp, FILE *orig, off_t copypos, off_t pos)
378 {
379 	char buf[BUFSIZ];
380 	size_t len, r, w;
381 
382 	if (fseeko(orig, copypos, SEEK_SET) == -1)
383 		return got_error_from_errno("fseeko");
384 
385 	while (pos == -1 || copypos < pos) {
386 		len = sizeof(buf);
387 		if (pos > 0)
388 			len = MIN(len, (size_t)pos - copypos);
389 		r = fread(buf, 1, len, orig);
390 		if (r != len && ferror(orig))
391 			return got_error_from_errno("fread");
392 		w = fwrite(buf, 1, r, tmp);
393 		if (w != r)
394 			return got_error_from_errno("fwrite");
395 		copypos += len;
396 		if (r != len && feof(orig)) {
397 			if (pos == -1)
398 				return NULL;
399 			return got_error(GOT_ERR_HUNK_FAILED);
400 		}
401 	}
402 	return NULL;
403 }
404 
405 static int lines_eq(struct got_patch_line *, const char *, size_t, int *);
406 
407 static const struct got_error *
408 locate_hunk(FILE *orig, struct got_patch_hunk *h, off_t *pos, int *lineno)
409 {
410 	const struct got_error *err = NULL;
411 	struct got_patch_line *l = &h->lines[0];
412 	char *line = NULL;
413 	char mode = l->mode;
414 	size_t linesize = 0;
415 	ssize_t linelen;
416 	off_t match = -1;
417 	int mangled = 0, match_lineno = -1;
418 
419 	for (;;) {
420 		(*lineno)++;
421 		linelen = getline(&line, &linesize, orig);
422 		if (linelen == -1) {
423 			if (ferror(orig))
424 				err = got_error_from_errno("getline");
425 			/* An EOF is fine iff the target file is empty. */
426 			if (feof(orig) && match == -1 && h->old_lines != 0)
427 				err = got_error(GOT_ERR_HUNK_FAILED);
428 			match = 0;
429 			match_lineno = (*lineno)-1;
430 			break;
431 		}
432 
433 		if ((mode == ' ' && lines_eq(l, line, linelen, &mangled)) ||
434 		    (mode == '-' && lines_eq(l, line, linelen, &mangled)) ||
435 		    (mode == '+' && *lineno == h->old_from)) {
436 			match = ftello(orig);
437 			if (match == -1) {
438 				err = got_error_from_errno("ftello");
439 				break;
440 			}
441 			match -= linelen;
442 			match_lineno = (*lineno)-1;
443 		}
444 
445 		if (*lineno >= h->old_from && match != -1) {
446 			if (mangled)
447 				h->ws_mangled = 1;
448 			break;
449 		}
450 	}
451 
452 	if (err == NULL) {
453 		*pos = match;
454 		*lineno = match_lineno;
455 		if (fseeko(orig, match, SEEK_SET) == -1)
456 			err = got_error_from_errno("fseeko");
457 	}
458 
459 	free(line);
460 	return err;
461 }
462 
463 static int
464 lines_eq(struct got_patch_line *l, const char *b, size_t len, int *mangled)
465 {
466 	char *a = l->line;
467 	size_t i, j;
468 
469 	if (len > 00 && b[len - 1] == '\n')
470 		len--;
471 
472 	*mangled = 0;
473 	if (l->len == len && !memcmp(a, b, len))
474 		return 1;
475 
476 	*mangled = 1;
477 
478 	i = j = 0;
479 	for (;;) {
480 		while (i < l->len &&
481 		    (a[i] == '\t' || a[i] == ' ' || a[i] == '\f'))
482 			i++;
483 		while (j < len &&
484 		    (b[j] == '\t' || b[j] == ' ' || b[j] == '\f'))
485 			j++;
486 		if (i == l->len || j == len || a[i] != b[j])
487 			break;
488 		i++, j++;
489 	}
490 
491 	return (i == l->len && j == len);
492 }
493 
494 static const struct got_error *
495 test_hunk(FILE *orig, struct got_patch_hunk *h)
496 {
497 	const struct got_error *err = NULL;
498 	char *line = NULL;
499 	size_t linesize = 0, i = 0;
500 	ssize_t linelen;
501 	int mangled;
502 
503 	for (i = 0; i < h->len; ++i) {
504 		switch (h->lines[i].mode) {
505 		case '+':
506 			continue;
507 		case ' ':
508 		case '-':
509 			linelen = getline(&line, &linesize, orig);
510 			if (linelen == -1) {
511 				if (ferror(orig))
512 					err = got_error_from_errno("getline");
513 				else
514 					err = got_error(
515 					    GOT_ERR_HUNK_FAILED);
516 				goto done;
517 			}
518 			if (!lines_eq(&h->lines[i], line, linelen, &mangled)) {
519 				err = got_error(GOT_ERR_HUNK_FAILED);
520 				goto done;
521 			}
522 			if (mangled)
523 				h->ws_mangled = 1;
524 			break;
525 		}
526 	}
527 
528 done:
529 	free(line);
530 	return err;
531 }
532 
533 static const struct got_error *
534 apply_hunk(FILE *orig, FILE *tmp, struct got_patch_hunk *h, int *lineno,
535     off_t from)
536 {
537 	const struct got_error *err = NULL;
538 	const char *t;
539 	size_t linesize = 0, i, new = 0;
540 	char *line = NULL;
541 	char mode;
542 	size_t l;
543 	ssize_t linelen;
544 
545 	if (orig != NULL && fseeko(orig, from, SEEK_SET) == -1)
546 		return got_error_from_errno("fseeko");
547 
548 	for (i = 0; i < h->len; ++i) {
549 		switch (mode = h->lines[i].mode) {
550 		case '-':
551 		case ' ':
552 			(*lineno)++;
553 			if (orig != NULL) {
554 				linelen = getline(&line, &linesize, orig);
555 				if (linelen == -1) {
556 					err = got_error_from_errno("getline");
557 					goto done;
558 				}
559 				if (line[linelen - 1] == '\n')
560 					line[linelen - 1] = '\0';
561 				t = line;
562 				l = linelen - 1;
563 			} else {
564 				t = h->lines[i].line;
565 				l = h->lines[i].len;
566 			}
567 			if (mode == '-')
568 				continue;
569 			if (fwrite(t, 1, l, tmp) != l ||
570 			    fputc('\n', tmp) == EOF) {
571 				err = got_error_from_errno("fprintf");
572 				goto done;
573 			}
574 			break;
575 		case '+':
576 			new++;
577 			t = h->lines[i].line;
578 			l = h->lines[i].len;
579 			if (fwrite(t, 1, l, tmp) != l) {
580 				err = got_error_from_errno("fprintf");
581 				goto done;
582 			}
583 			if (new != h->new_lines || !h->new_nonl) {
584 				if (fprintf(tmp, "\n") < 0) {
585 					err = got_error_from_errno("fprintf");
586 					goto done;
587 				}
588 			}
589 			break;
590 		}
591 	}
592 
593 done:
594 	free(line);
595 	return err;
596 }
597 
598 static const struct got_error *
599 patch_file(struct got_patch *p, FILE *orig, FILE *tmp)
600 {
601 	const struct got_error *err = NULL;
602 	struct got_patch_hunk *h;
603 	struct stat sb;
604 	int lineno = 0;
605 	off_t copypos, pos;
606 	char *line = NULL;
607 	size_t linesize = 0;
608 	ssize_t linelen;
609 
610 	if (p->old == NULL) {				/* create */
611 		h = STAILQ_FIRST(&p->head);
612 		if (h == NULL || STAILQ_NEXT(h, entries) != NULL)
613 			return got_error(GOT_ERR_PATCH_MALFORMED);
614 		return apply_hunk(orig, tmp, h, &lineno, 0);
615 	}
616 
617 	/* When deleting binary files there are no hunks to apply. */
618 	if (p->new == NULL && STAILQ_EMPTY(&p->head))
619 		return NULL;
620 
621 	if (fstat(fileno(orig), &sb) == -1)
622 		return got_error_from_errno("fstat");
623 
624 	copypos = 0;
625 	STAILQ_FOREACH(h, &p->head, entries) {
626 	tryagain:
627 		err = locate_hunk(orig, h, &pos, &lineno);
628 		if (err != NULL && err->code == GOT_ERR_HUNK_FAILED)
629 			h->err = err;
630 		if (err != NULL)
631 			return err;
632 		err = copy(tmp, orig, copypos, pos);
633 		if (err != NULL)
634 			return err;
635 		copypos = pos;
636 
637 		err = test_hunk(orig, h);
638 		if (err != NULL && err->code == GOT_ERR_HUNK_FAILED) {
639 			/*
640 			 * try to apply the hunk again starting the search
641 			 * after the previous partial match.
642 			 */
643 			if (fseeko(orig, pos, SEEK_SET) == -1)
644 				return got_error_from_errno("fseeko");
645 			linelen = getline(&line, &linesize, orig);
646 			if (linelen == -1)
647 				return got_error_from_errno("getline");
648 			lineno++;
649 			goto tryagain;
650 		}
651 		if (err != NULL)
652 			return err;
653 
654 		if (lineno + 1 != h->old_from)
655 			h->offset = lineno + 1 - h->old_from;
656 
657 		err = apply_hunk(orig, tmp, h, &lineno, pos);
658 		if (err != NULL)
659 			return err;
660 
661 		copypos = ftello(orig);
662 		if (copypos == -1)
663 			return got_error_from_errno("ftello");
664 	}
665 
666 	if (p->new == NULL && sb.st_size != copypos) {
667 		h = STAILQ_FIRST(&p->head);
668 		h->err = got_error(GOT_ERR_HUNK_FAILED);
669 		err = h->err;
670 	} else if (!feof(orig))
671 		err = copy(tmp, orig, copypos, -1);
672 
673 	return err;
674 }
675 
676 static const struct got_error *
677 report_progress(struct patch_args *pa, const char *old, const char *new,
678     unsigned char status, const struct got_error *orig_error)
679 {
680 	const struct got_error *err;
681 	struct got_patch_hunk *h;
682 
683 	err = pa->progress_cb(pa->progress_arg, old, new, status,
684 	    orig_error, 0, 0, 0, 0, 0, 0, NULL);
685 	if (err)
686 		return err;
687 
688 	STAILQ_FOREACH(h, pa->head, entries) {
689 		if (h->offset == 0 && !h->ws_mangled && h->err == NULL)
690 			continue;
691 
692 		err = pa->progress_cb(pa->progress_arg, old, new, 0, NULL,
693 		    h->old_from, h->old_lines, h->new_from, h->new_lines,
694 		    h->offset, h->ws_mangled, h->err);
695 		if (err)
696 			return err;
697 	}
698 
699 	return NULL;
700 }
701 
702 static const struct got_error *
703 patch_delete(void *arg, unsigned char status, unsigned char staged_status,
704     const char *path)
705 {
706 	return report_progress(arg, path, NULL, status, NULL);
707 }
708 
709 static const struct got_error *
710 patch_add(void *arg, unsigned char status, const char *path)
711 {
712 	return report_progress(arg, NULL, path, status, NULL);
713 }
714 
715 static const struct got_error *
716 open_blob(char **path, FILE **fp, const char *blobid,
717     struct got_repository *repo)
718 {
719 	const struct got_error *err = NULL;
720 	struct got_blob_object *blob = NULL;
721 	struct got_object_id id, *idptr, *matched_id = NULL;
722 	int fd = -1;
723 
724 	*fp = NULL;
725 	*path = NULL;
726 
727 	if (strlen(blobid) != SHA1_DIGEST_STRING_LENGTH - 1) {
728 		err = got_repo_match_object_id(&matched_id, NULL, blobid,
729 		    GOT_OBJ_TYPE_BLOB, NULL /* do not resolve tags */,
730 		    repo);
731 		if (err)
732 			return err;
733 		idptr = matched_id;
734 	} else {
735 		if (!got_parse_object_id(&id, blobid, GOT_HASH_SHA1))
736 			return got_error(GOT_ERR_BAD_OBJ_ID_STR);
737 		idptr = &id;
738 	}
739 
740 	fd = got_opentempfd();
741 	if (fd == -1) {
742 		err = got_error_from_errno("got_opentempfd");
743 		goto done;
744 	}
745 
746 	err = got_object_open_as_blob(&blob, repo, idptr, 8192, fd);
747 	if (err)
748 		goto done;
749 
750 	err = got_opentemp_named(path, fp, GOT_TMPDIR_STR "/got-patch-blob",
751 	    "");
752 	if (err)
753 		goto done;
754 
755 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, *fp, blob);
756 	if (err)
757 		goto done;
758 
759 done:
760 	if (fd != -1 && close(fd) == -1 && err == NULL)
761 		err = got_error_from_errno("close");
762 	if (blob)
763 		got_object_blob_close(blob);
764 	if (matched_id != NULL)
765 		free(matched_id);
766 	if (err) {
767 		if (*fp != NULL)
768 			fclose(*fp);
769 		if (*path != NULL)
770 			unlink(*path);
771 		free(*path);
772 		*fp = NULL;
773 		*path = NULL;
774 	}
775 	return err;
776 }
777 
778 static const struct got_error *
779 prepare_merge(int *do_merge, char **apath, FILE **afile,
780     struct got_worktree *worktree, struct got_repository *repo,
781     struct got_patch *p, struct got_object_id *commit_id,
782     struct got_tree_object *tree, const char *path)
783 {
784 	const struct got_error *err = NULL;
785 
786 	*do_merge = 0;
787 	*apath = NULL;
788 	*afile = NULL;
789 
790 	/* don't run the diff3 merge on creations/deletions */
791 	if (p->old == NULL || p->new == NULL)
792 		return NULL;
793 
794 	if (commit_id) {
795 		struct got_object_id *id;
796 
797 		err = got_object_tree_find_path(&id, NULL, repo, tree, path);
798 		if (err)
799 			return err;
800 		got_sha1_digest_to_str(id->sha1, p->blob, sizeof(p->blob));
801 		got_sha1_digest_to_str(commit_id->sha1, p->cid, sizeof(p->cid));
802 		free(id);
803 		err = open_blob(apath, afile, p->blob, repo);
804 		*do_merge = err == NULL;
805 	} else if (*p->blob != '\0') {
806 		err = open_blob(apath, afile, p->blob, repo);
807 		/*
808 		 * ignore failures to open this blob, we might have
809 		 * parsed gibberish.
810 		 */
811 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT) &&
812 		    err->code != GOT_ERR_NO_OBJ)
813 			return err;
814 		*do_merge = err == NULL;
815 		err = NULL;
816 	}
817 
818 	return err;
819 }
820 
821 static const struct got_error *
822 apply_patch(int *overlapcnt, struct got_worktree *worktree,
823     struct got_repository *repo, struct got_fileindex *fileindex,
824     const char *old, const char *new, struct got_patch *p, int nop,
825     int reverse, struct got_object_id *commit_id,
826     struct got_tree_object *tree, struct patch_args *pa,
827     got_cancel_cb cancel_cb, void *cancel_arg)
828 {
829 	const struct got_error *err = NULL;
830 	struct stat sb;
831 	int do_merge = 0, file_renamed = 0;
832 	char *oldlabel = NULL, *newlabel = NULL, *anclabel = NULL;
833 	char *oldpath = NULL, *newpath = NULL;
834 	char *tmppath = NULL, *template = NULL;
835 	char *apath = NULL, *mergepath = NULL;
836 	FILE *oldfile = NULL, *tmpfile = NULL, *afile = NULL, *mergefile = NULL;
837 	int outfd;
838 	mode_t mode = GOT_DEFAULT_FILE_MODE;
839 
840 	*overlapcnt = 0;
841 
842 	err = prepare_merge(&do_merge, &apath, &afile, worktree, repo, p,
843 	    commit_id, tree, old);
844 	if (err)
845 		return err;
846 
847 	if (reverse && !do_merge)
848 		reverse_patch(p);
849 
850 	if (asprintf(&oldpath, "%s/%s", got_worktree_get_root_path(worktree),
851 	    old) == -1) {
852 		err = got_error_from_errno("asprintf");
853 		goto done;
854 	}
855 
856 	if (asprintf(&newpath, "%s/%s", got_worktree_get_root_path(worktree),
857 	    new) == -1) {
858 		err = got_error_from_errno("asprintf");
859 		goto done;
860 	}
861 
862 	file_renamed = strcmp(oldpath, newpath);
863 
864 	if (asprintf(&template, "%s/got-patch",
865 	    got_worktree_get_root_path(worktree)) == -1) {
866 		err = got_error_from_errno(template);
867 		goto done;
868 	}
869 
870 	if (p->old != NULL) {
871 		if ((oldfile = fopen(oldpath, "r")) == NULL) {
872 			err = got_error_from_errno2("open", oldpath);
873 			goto done;
874 		}
875 		if (fstat(fileno(oldfile), &sb) == -1) {
876 			err = got_error_from_errno2("fstat", oldpath);
877 			goto done;
878 		}
879 		mode = sb.st_mode;
880 	} else if (p->xbit)
881 		mode |= (S_IXUSR | S_IXGRP | S_IXOTH);
882 
883 	err = got_opentemp_named(&tmppath, &tmpfile, template, "");
884 	if (err)
885 		goto done;
886 	outfd = fileno(tmpfile);
887 	err = patch_file(p, afile != NULL ? afile : oldfile, tmpfile);
888 	if (err)
889 		goto done;
890 
891 	if (do_merge) {
892 		const char *type, *id;
893 
894 		if (fseeko(afile, 0, SEEK_SET) == -1 ||
895 		    fseeko(oldfile, 0, SEEK_SET) == -1 ||
896 		    fseeko(tmpfile, 0, SEEK_SET) == -1) {
897 			err = got_error_from_errno("fseeko");
898 			goto done;
899 		}
900 
901 		if (asprintf(&oldlabel, "--- %s", p->old) == -1) {
902 			err = got_error_from_errno("asprintf");
903 			oldlabel = NULL;
904 			goto done;
905 		}
906 
907 		if (asprintf(&newlabel, "+++ %s", p->new) == -1) {
908 			err = got_error_from_errno("asprintf");
909 			newlabel = NULL;
910 			goto done;
911 		}
912 
913 		if (*p->cid != '\0') {
914 			type = "commit";
915 			id = p->cid;
916 		} else {
917 			type = "blob";
918 			id = p->blob;
919 		}
920 
921 		if (asprintf(&anclabel, "%s %s", type, id) == -1) {
922 			err = got_error_from_errno("asprintf");
923 			anclabel = NULL;
924 			goto done;
925 		}
926 
927 		if (reverse) {
928 			char *s;
929 			FILE *t;
930 
931 			s = anclabel;
932 			anclabel = newlabel;
933 			newlabel = s;
934 
935 			t = afile;
936 			afile = tmpfile;
937 			tmpfile = t;
938 		}
939 
940 		err = got_opentemp_named(&mergepath, &mergefile, template, "");
941 		if (err)
942 			goto done;
943 		outfd = fileno(mergefile);
944 
945 		err = got_merge_diff3(overlapcnt, outfd, tmpfile, afile,
946 		    oldfile, oldlabel, anclabel, newlabel,
947 		    GOT_DIFF_ALGORITHM_PATIENCE);
948 		if (err)
949 			goto done;
950 	}
951 
952 	if (nop)
953 		goto done;
954 
955 	if (p->old != NULL && p->new == NULL) {
956 		err = got_worktree_patch_schedule_rm(old, repo, worktree,
957 		    fileindex, patch_delete, pa);
958 		goto done;
959 	}
960 
961 	if (fchmod(outfd, apply_umask(mode)) == -1) {
962 		err = got_error_from_errno2("chmod", tmppath);
963 		goto done;
964 	}
965 
966 	if (mergepath) {
967 		err = got_path_move_file(mergepath, newpath);
968 		if (err)
969 			goto done;
970 		free(mergepath);
971 		mergepath = NULL;
972 	} else {
973 		err = got_path_move_file(tmppath, newpath);
974 		if (err)
975 			goto done;
976 		free(tmppath);
977 		tmppath = NULL;
978 	}
979 
980 	if (file_renamed) {
981 		err = got_worktree_patch_schedule_rm(old, repo, worktree,
982 		    fileindex, patch_delete, pa);
983 		if (err == NULL)
984 			err = got_worktree_patch_schedule_add(new, repo,
985 			    worktree, fileindex, patch_add,
986 			    pa);
987 		if (err)
988 			unlink(newpath);
989 	} else if (p->old == NULL) {
990 		err = got_worktree_patch_schedule_add(new, repo, worktree,
991 		    fileindex, patch_add, pa);
992 		if (err)
993 			unlink(newpath);
994 	} else if (*overlapcnt != 0)
995 		err = report_progress(pa, old, new, GOT_STATUS_CONFLICT, NULL);
996 	else if (do_merge)
997 		err = report_progress(pa, old, new, GOT_STATUS_MERGE, NULL);
998 	else
999 		err = report_progress(pa, old, new, GOT_STATUS_MODIFY, NULL);
1000 
1001 done:
1002 	free(template);
1003 
1004 	if (tmppath != NULL && unlink(tmppath) == -1 && err == NULL)
1005 		err = got_error_from_errno("unlink");
1006 	if (tmpfile != NULL && fclose(tmpfile) == EOF && err == NULL)
1007 		err = got_error_from_errno("fclose");
1008 	free(tmppath);
1009 
1010 	free(oldpath);
1011 	if (oldfile != NULL && fclose(oldfile) == EOF && err == NULL)
1012 		err = got_error_from_errno("fclose");
1013 
1014 	if (apath != NULL && unlink(apath) == -1 && err == NULL)
1015 		err = got_error_from_errno("unlink");
1016 	if (afile != NULL && fclose(afile) == EOF && err == NULL)
1017 		err = got_error_from_errno("fclose");
1018 	free(apath);
1019 
1020 	if (mergepath != NULL && unlink(mergepath) == -1 && err == NULL)
1021 		err = got_error_from_errno("unlink");
1022 	if (mergefile != NULL && fclose(mergefile) == EOF && err == NULL)
1023 		err = got_error_from_errno("fclose");
1024 	free(mergepath);
1025 
1026 	free(newpath);
1027 	free(oldlabel);
1028 	free(newlabel);
1029 	free(anclabel);
1030 	return err;
1031 }
1032 
1033 const struct got_error *
1034 got_patch(int fd, struct got_worktree *worktree, struct got_repository *repo,
1035     int nop, int strip, int reverse, struct got_object_id *commit_id,
1036     got_patch_progress_cb progress_cb, void *progress_arg,
1037     got_cancel_cb cancel_cb, void *cancel_arg)
1038 {
1039 	const struct got_error *err = NULL, *complete_err = NULL;
1040 	struct got_fileindex *fileindex = NULL;
1041 	struct got_commit_object *commit = NULL;
1042 	struct got_tree_object *tree = NULL;
1043 	char *fileindex_path = NULL;
1044 	char *oldpath, *newpath;
1045 	struct imsgbuf *ibuf;
1046 	int imsg_fds[2] = {-1, -1};
1047 	int overlapcnt, done = 0, failed = 0;
1048 	pid_t pid;
1049 
1050 	ibuf = calloc(1, sizeof(*ibuf));
1051 	if (ibuf == NULL) {
1052 		err = got_error_from_errno("calloc");
1053 		goto done;
1054 	}
1055 
1056 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1057 		err = got_error_from_errno("socketpair");
1058 		goto done;
1059 	}
1060 
1061 	pid = fork();
1062 	if (pid == -1) {
1063 		err = got_error_from_errno("fork");
1064 		goto done;
1065 	} else if (pid == 0) {
1066 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_PATCH,
1067 		    NULL);
1068 		/* not reached */
1069 	}
1070 
1071 	if (close(imsg_fds[1]) == -1) {
1072 		err = got_error_from_errno("close");
1073 		goto done;
1074 	}
1075 	imsg_fds[1] = -1;
1076 	imsg_init(ibuf, imsg_fds[0]);
1077 
1078 	err = send_patch(ibuf, fd);
1079 	fd = -1;
1080 	if (err)
1081 		goto done;
1082 
1083 	err = got_worktree_patch_prepare(&fileindex, &fileindex_path,
1084 	    worktree);
1085 	if (err)
1086 		goto done;
1087 
1088 	if (commit_id) {
1089 		err = got_object_open_as_commit(&commit, repo, commit_id);
1090 		if (err)
1091 			goto done;
1092 
1093 		err = got_object_open_as_tree(&tree, repo, commit->tree_id);
1094 		if (err)
1095 			goto done;
1096 	}
1097 
1098 	while (!done && err == NULL) {
1099 		struct got_patch p;
1100 		struct patch_args pa;
1101 
1102 		pa.progress_cb = progress_cb;
1103 		pa.progress_arg = progress_arg;
1104 		pa.head = &p.head;
1105 
1106 		err = recv_patch(ibuf, &done, &p, strip);
1107 		if (err || done)
1108 			break;
1109 
1110 		err = got_worktree_patch_check_path(p.old, p.new, &oldpath,
1111 		    &newpath, worktree, repo, fileindex);
1112 		if (err == NULL)
1113 			err = apply_patch(&overlapcnt, worktree, repo,
1114 			    fileindex, oldpath, newpath, &p, nop, reverse,
1115 			    commit_id, tree, &pa, cancel_cb, cancel_arg);
1116 		if (err != NULL) {
1117 			failed = 1;
1118 			/* recoverable errors */
1119 			if (err->code == GOT_ERR_FILE_STATUS ||
1120 			    (err->code == GOT_ERR_ERRNO && errno == ENOENT))
1121 				err = report_progress(&pa, p.old, p.new,
1122 				    GOT_STATUS_CANNOT_UPDATE, err);
1123 			else if (err->code == GOT_ERR_HUNK_FAILED)
1124 				err = report_progress(&pa, p.old, p.new,
1125 				    GOT_STATUS_CANNOT_UPDATE, NULL);
1126 		}
1127 		if (overlapcnt != 0)
1128 			failed = 1;
1129 
1130 		free(oldpath);
1131 		free(newpath);
1132 		patch_free(&p);
1133 
1134 		if (err)
1135 			break;
1136 	}
1137 
1138 done:
1139 	if (fileindex != NULL)
1140 		complete_err = got_worktree_patch_complete(fileindex,
1141 		    fileindex_path);
1142 	if (complete_err && err == NULL)
1143 		err = complete_err;
1144 	free(fileindex_path);
1145 	if (tree)
1146 		got_object_tree_close(tree);
1147 	if (commit)
1148 		got_object_commit_close(commit);
1149 	if (fd != -1 && close(fd) == -1 && err == NULL)
1150 		err = got_error_from_errno("close");
1151 	if (ibuf != NULL)
1152 		imsg_clear(ibuf);
1153 	if (imsg_fds[0] != -1 && close(imsg_fds[0]) == -1 && err == NULL)
1154 		err = got_error_from_errno("close");
1155 	if (imsg_fds[1] != -1 && close(imsg_fds[1]) == -1 && err == NULL)
1156 		err = got_error_from_errno("close");
1157 	if (err == NULL && failed)
1158 		err = got_error(GOT_ERR_PATCH_FAILED);
1159 	return err;
1160 }