2 * Copyright (c) 2018, 2019 Stefan Sperling <stsp@openbsd.org>
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.
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.
17 #include <sys/types.h>
18 #include <sys/queue.h>
29 #include "got_error.h"
30 #include "got_object.h"
31 #include "got_repository.h"
32 #include "got_reference.h"
34 #include "got_lib_sha1.h"
35 #include "got_lib_path.h"
36 #include "got_lib_delta.h"
37 #include "got_lib_inflate.h"
38 #include "got_lib_object.h"
41 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
44 #define GOT_REF_HEADS "heads"
45 #define GOT_REF_TAGS "tags"
46 #define GOT_REF_REMOTES "remotes"
48 /* A symbolic reference. */
54 /* A non-symbolic reference (there is no better designation). */
57 u_int8_t sha1[SHA1_DIGEST_LENGTH];
60 /* A reference which points to an arbitrary object. */
61 struct got_reference {
63 #define GOT_REF_IS_SYMBOLIC 0x01
67 struct got_symref symref;
71 static const struct got_error *
72 parse_symref(struct got_reference **ref, const char *name, const char *line)
74 struct got_symref *symref;
79 return got_error(GOT_ERR_BAD_REF_DATA);
81 symref_name = strdup(name);
82 if (symref_name == NULL)
83 return got_error_from_errno();
84 symref_ref = strdup(line);
85 if (symref_ref == NULL) {
86 const struct got_error *err = got_error_from_errno();
91 *ref = calloc(1, sizeof(**ref));
93 return got_error_from_errno();
94 (*ref)->flags |= GOT_REF_IS_SYMBOLIC;
95 symref = &((*ref)->ref.symref);
96 symref->name = symref_name;
97 symref->ref = symref_ref;
101 static const struct got_error *
102 parse_ref_line(struct got_reference **ref, const char *name, const char *line)
104 uint8_t digest[SHA1_DIGEST_LENGTH];
107 if (strncmp(line, "ref: ", 5) == 0) {
109 return parse_symref(ref, name, line);
112 ref_name = strdup(name);
113 if (ref_name == NULL)
114 return got_error_from_errno();
116 if (!got_parse_sha1_digest(digest, line))
117 return got_error(GOT_ERR_BAD_REF_DATA);
119 *ref = calloc(1, sizeof(**ref));
121 return got_error_from_errno();
122 (*ref)->ref.ref.name = ref_name;
123 memcpy(&(*ref)->ref.ref.sha1, digest, SHA1_DIGEST_LENGTH);
127 static const struct got_error *
128 parse_ref_file(struct got_reference **ref, const char *name,
131 const struct got_error *err = NULL;
132 FILE *f = fopen(abspath, "rb");
135 const char delim[3] = {'\0', '\0', '\0'};
140 line = fparseln(f, &len, NULL, delim, 0);
142 err = got_error(GOT_ERR_BAD_REF_DATA);
146 err = parse_ref_line(ref, name, line);
154 is_well_known_ref(const char *refname)
156 return (strcmp(refname, GOT_REF_HEAD) == 0 ||
157 strcmp(refname, GOT_REF_ORIG_HEAD) == 0 ||
158 strcmp(refname, GOT_REF_MERGE_HEAD) == 0 ||
159 strcmp(refname, GOT_REF_FETCH_HEAD) == 0);
163 get_refs_dir_path(struct got_repository *repo, const char *refname)
165 if (is_well_known_ref(refname) || strncmp(refname, "refs/", 5) == 0)
166 return strdup(got_repo_get_path_git_dir(repo));
168 return got_repo_get_path_refs(repo);
171 static const struct got_error *
172 parse_packed_ref_line(struct got_reference **ref, const char *abs_refname,
175 uint8_t digest[SHA1_DIGEST_LENGTH];
180 if (line[0] == '#' || line[0] == '^')
183 if (!got_parse_sha1_digest(digest, line))
184 return got_error(GOT_ERR_BAD_REF_DATA);
187 if (strcmp(line + SHA1_DIGEST_STRING_LENGTH, abs_refname) != 0)
190 name = strdup(abs_refname);
192 return got_error_from_errno();
194 name = strdup(line + SHA1_DIGEST_STRING_LENGTH);
196 *ref = calloc(1, sizeof(**ref));
198 return got_error_from_errno();
199 (*ref)->ref.ref.name = name;;
200 memcpy(&(*ref)->ref.ref.sha1, digest, SHA1_DIGEST_LENGTH);
204 static const struct got_error *
205 open_packed_ref(struct got_reference **ref, FILE *f, const char **subdirs,
206 int nsubdirs, const char *refname)
208 const struct got_error *err = NULL;
212 const char delim[3] = {'\0', '\0', '\0'};
213 int i, ref_is_absolute = (strncmp(refname, "refs/", 5) == 0);
218 abs_refname = (char *)refname;
220 line = fparseln(f, &len, NULL, delim, 0);
223 for (i = 0; i < nsubdirs; i++) {
224 if (!ref_is_absolute &&
225 asprintf(&abs_refname, "refs/%s/%s", subdirs[i],
227 return got_error_from_errno();
228 err = parse_packed_ref_line(ref, abs_refname, line);
229 if (!ref_is_absolute)
231 if (err || *ref != NULL)
237 } while (*ref == NULL);
242 static const struct got_error *
243 open_ref(struct got_reference **ref, const char *path_refs, const char *subdir,
246 const struct got_error *err = NULL;
248 char *normpath = NULL;
249 char *absname = NULL;
250 int ref_is_absolute = (strncmp(name, "refs/", 5) == 0);
251 int ref_is_well_known = is_well_known_ref(name);
255 if (ref_is_absolute || ref_is_well_known) {
256 if (asprintf(&path, "%s/%s", path_refs, name) == -1)
257 return got_error_from_errno();
258 absname = (char *)name;
260 if (asprintf(&path, "%s/%s/%s", path_refs, subdir, name) == -1)
261 return got_error_from_errno();
263 if (asprintf(&absname, "refs/%s/%s", subdir, name) == -1) {
264 err = got_error_from_errno();
269 normpath = got_path_normalize(path);
270 if (normpath == NULL) {
271 err = got_error_from_errno();
275 err = parse_ref_file(ref, absname, normpath);
277 if (!ref_is_absolute && !ref_is_well_known)
284 const struct got_error *
285 got_ref_open(struct got_reference **ref, struct got_repository *repo,
288 const struct got_error *err = NULL;
289 char *path_refs = NULL;
290 const char *subdirs[] = {
291 GOT_REF_HEADS, GOT_REF_TAGS, GOT_REF_REMOTES
293 int i, well_known = is_well_known_ref(refname);
298 char *packed_refs_path;
301 packed_refs_path = got_repo_get_path_packed_refs(repo);
302 if (packed_refs_path == NULL)
303 return got_error_from_errno();
305 f = fopen(packed_refs_path, "rb");
306 free(packed_refs_path);
308 err = open_packed_ref(ref, f, subdirs, nitems(subdirs),
316 path_refs = get_refs_dir_path(repo, refname);
317 if (path_refs == NULL) {
318 err = got_error_from_errno();
323 for (i = 0; i < nitems(subdirs); i++) {
324 err = open_ref(ref, path_refs, subdirs[i], refname);
330 err = open_ref(ref, path_refs, "", refname);
334 err = got_error_not_ref(refname);
341 got_ref_close(struct got_reference *ref)
343 if (ref->flags & GOT_REF_IS_SYMBOLIC)
344 free(ref->ref.symref.name);
346 free(ref->ref.ref.name);
350 struct got_reference *
351 got_ref_dup(struct got_reference *ref)
353 struct got_reference *ret;
355 ret = calloc(1, sizeof(*ret));
359 ret->flags = ref->flags;
360 if (ref->flags & GOT_REF_IS_SYMBOLIC) {
361 ret->ref.symref.name = strdup(ref->ref.symref.name);
362 if (ret->ref.symref.name == NULL) {
366 ret->ref.symref.ref = strdup(ref->ref.symref.ref);
367 if (ret->ref.symref.ref == NULL) {
368 free(ret->ref.symref.name);
373 ref->ref.ref.name = strdup(ref->ref.ref.name);
374 if (ref->ref.ref.name == NULL) {
378 memcpy(ret->ref.ref.sha1, ref->ref.ref.sha1,
385 static const struct got_error *
386 resolve_symbolic_ref(struct got_reference **resolved,
387 struct got_repository *repo, struct got_reference *ref)
389 struct got_reference *nextref;
390 const struct got_error *err;
392 err = got_ref_open(&nextref, repo, ref->ref.symref.ref);
396 if (nextref->flags & GOT_REF_IS_SYMBOLIC)
397 err = resolve_symbolic_ref(resolved, repo, nextref);
399 *resolved = got_ref_dup(nextref);
401 got_ref_close(nextref);
405 const struct got_error *
406 got_ref_resolve(struct got_object_id **id, struct got_repository *repo,
407 struct got_reference *ref)
409 const struct got_error *err;
411 if (ref->flags & GOT_REF_IS_SYMBOLIC) {
412 struct got_reference *resolved = NULL;
413 err = resolve_symbolic_ref(&resolved, repo, ref);
415 err = got_ref_resolve(id, repo, resolved);
420 *id = calloc(1, sizeof(**id));
422 return got_error_from_errno();
423 memcpy((*id)->sha1, ref->ref.ref.sha1, SHA1_DIGEST_LENGTH);
428 got_ref_to_str(struct got_reference *ref)
432 if (ref->flags & GOT_REF_IS_SYMBOLIC)
433 return strdup(ref->ref.symref.ref);
435 str = malloc(SHA1_DIGEST_STRING_LENGTH);
439 if (got_sha1_digest_to_str(ref->ref.ref.sha1, str,
440 SHA1_DIGEST_STRING_LENGTH) == NULL) {
449 got_ref_get_name(struct got_reference *ref)
451 if (ref->flags & GOT_REF_IS_SYMBOLIC)
452 return ref->ref.symref.name;
454 return ref->ref.ref.name;
457 static const struct got_error *
458 insert_ref(struct got_reflist_head *refs, struct got_reference *ref,
459 struct got_repository *repo)
461 const struct got_error *err;
462 struct got_object_id *id;
463 struct got_reflist_entry *new, *re, *prev;
466 err = got_ref_resolve(&id, repo, ref);
470 new = malloc(sizeof(*re));
473 return got_error_from_errno();
479 * We must de-duplicate entries on insert because packed-refs may
480 * contain redundant entries. On-disk refs take precedence.
481 * This code assumes that on-disk revs are read before packed-refs.
482 * We're iterating the list anyway, so insert elements sorted by name.
484 re = SIMPLEQ_FIRST(refs);
486 cmp = got_path_cmp(got_ref_get_name(re->ref),
487 got_ref_get_name(ref));
489 free(ref); /* duplicate */
491 } else if (cmp > 0) {
493 SIMPLEQ_INSERT_AFTER(refs, prev, new, entry);
495 SIMPLEQ_INSERT_HEAD(refs, new, entry);
499 re = SIMPLEQ_NEXT(re, entry);
503 SIMPLEQ_INSERT_TAIL(refs, new, entry);
507 static const struct got_error *
508 gather_on_disk_refs(struct got_reflist_head *refs, const char *path_refs,
509 const char *subdir, struct got_repository *repo)
511 const struct got_error *err = NULL;
515 if (asprintf(&path_subdir, "%s/%s", path_refs, subdir) == -1)
516 return got_error_from_errno();
518 d = opendir(path_subdir);
524 struct got_reference *ref;
531 if (strcmp(dent->d_name, ".") == 0 ||
532 strcmp(dent->d_name, "..") == 0)
535 switch (dent->d_type) {
537 err = open_ref(&ref, path_refs, subdir, dent->d_name);
541 err = insert_ref(refs, ref, repo);
547 if (asprintf(&child, "%s%s%s", subdir,
548 subdir[0] == '\0' ? "" : "/", dent->d_name) == -1) {
549 err = got_error_from_errno();
552 err = gather_on_disk_refs(refs, path_refs, child, repo);
566 const struct got_error *
567 got_ref_list(struct got_reflist_head *refs, struct got_repository *repo)
569 const struct got_error *err;
570 char *packed_refs_path, *path_refs = NULL;
572 struct got_reference *ref;
574 /* HEAD ref should always exist. */
575 path_refs = get_refs_dir_path(repo, GOT_REF_HEAD);
576 if (path_refs == NULL) {
577 err = got_error_from_errno();
580 err = open_ref(&ref, path_refs, "", GOT_REF_HEAD);
583 err = insert_ref(refs, ref, repo);
587 /* Gather on-disk refs before parsing packed-refs. */
589 path_refs = get_refs_dir_path(repo, "");
590 if (path_refs == NULL) {
591 err = got_error_from_errno();
594 err = gather_on_disk_refs(refs, path_refs, "", repo);
599 * The packed-refs file may contain redundant entries, in which
600 * case on-disk refs take precedence.
602 packed_refs_path = got_repo_get_path_packed_refs(repo);
603 if (packed_refs_path == NULL) {
604 err = got_error_from_errno();
608 f = fopen(packed_refs_path, "r");
609 free(packed_refs_path);
613 const char delim[3] = {'\0', '\0', '\0'};
615 line = fparseln(f, &len, NULL, delim, 0);
618 err = parse_packed_ref_line(&ref, NULL, line);
622 err = insert_ref(refs, ref, repo);