clear_ref_cache(): inline function
[git/jnareb-git.git] / refs.c
blobd8a4fa33e35cdf73a8d6efce593a857f395f96f8
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
9 #define REF_BROKEN 010
11 struct ref_entry {
12 unsigned char flag; /* ISSYMREF? ISPACKED? */
13 unsigned char sha1[20];
14 unsigned char peeled[20];
15 char name[FLEX_ARRAY];
18 struct ref_array {
19 int nr, alloc;
20 struct ref_entry **refs;
23 static const char *parse_ref_line(char *line, unsigned char *sha1)
26 * 42: the answer to everything.
28 * In this case, it happens to be the answer to
29 * 40 (length of sha1 hex representation)
30 * +1 (space in between hex and name)
31 * +1 (newline at the end of the line)
33 int len = strlen(line) - 42;
35 if (len <= 0)
36 return NULL;
37 if (get_sha1_hex(line, sha1) < 0)
38 return NULL;
39 if (!isspace(line[40]))
40 return NULL;
41 line += 41;
42 if (isspace(*line))
43 return NULL;
44 if (line[len] != '\n')
45 return NULL;
46 line[len] = 0;
48 return line;
51 static void add_ref(const char *name, const unsigned char *sha1,
52 int flag, struct ref_array *refs,
53 struct ref_entry **new_entry)
55 int len;
56 struct ref_entry *entry;
58 /* Allocate it and add it in.. */
59 len = strlen(name) + 1;
60 entry = xmalloc(sizeof(struct ref_entry) + len);
61 hashcpy(entry->sha1, sha1);
62 hashclr(entry->peeled);
63 if (check_refname_format(name, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
64 die("Reference has invalid format: '%s'", name);
65 memcpy(entry->name, name, len);
66 entry->flag = flag;
67 if (new_entry)
68 *new_entry = entry;
69 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
70 refs->refs[refs->nr++] = entry;
73 static int ref_entry_cmp(const void *a, const void *b)
75 struct ref_entry *one = *(struct ref_entry **)a;
76 struct ref_entry *two = *(struct ref_entry **)b;
77 return strcmp(one->name, two->name);
80 static void sort_ref_array(struct ref_array *array)
82 int i = 0, j = 1;
84 /* Nothing to sort unless there are at least two entries */
85 if (array->nr < 2)
86 return;
88 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
90 /* Remove any duplicates from the ref_array */
91 for (; j < array->nr; j++) {
92 struct ref_entry *a = array->refs[i];
93 struct ref_entry *b = array->refs[j];
94 if (!strcmp(a->name, b->name)) {
95 if (hashcmp(a->sha1, b->sha1))
96 die("Duplicated ref, and SHA1s don't match: %s",
97 a->name);
98 warning("Duplicated ref: %s", a->name);
99 free(b);
100 continue;
102 i++;
103 array->refs[i] = array->refs[j];
105 array->nr = i + 1;
108 static struct ref_entry *search_ref_array(struct ref_array *array, const char *name)
110 struct ref_entry *e, **r;
111 int len;
113 if (name == NULL)
114 return NULL;
116 if (!array->nr)
117 return NULL;
119 len = strlen(name) + 1;
120 e = xmalloc(sizeof(struct ref_entry) + len);
121 memcpy(e->name, name, len);
123 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
125 free(e);
127 if (r == NULL)
128 return NULL;
130 return *r;
134 * Future: need to be in "struct repository"
135 * when doing a full libification.
137 static struct ref_cache {
138 struct ref_cache *next;
139 char did_loose;
140 char did_packed;
141 struct ref_array loose;
142 struct ref_array packed;
143 /* The submodule name, or "" for the main repo. */
144 char name[FLEX_ARRAY];
145 } *ref_cache;
147 static struct ref_entry *current_ref;
149 static struct ref_array extra_refs;
151 static void free_ref_array(struct ref_array *array)
153 int i;
154 for (i = 0; i < array->nr; i++)
155 free(array->refs[i]);
156 free(array->refs);
157 array->nr = array->alloc = 0;
158 array->refs = NULL;
161 static void clear_packed_ref_cache(struct ref_cache *refs)
163 if (refs->did_packed)
164 free_ref_array(&refs->packed);
165 refs->did_packed = 0;
168 static void clear_loose_ref_cache(struct ref_cache *refs)
170 if (refs->did_loose)
171 free_ref_array(&refs->loose);
172 refs->did_loose = 0;
175 static struct ref_cache *create_ref_cache(const char *submodule)
177 int len;
178 struct ref_cache *refs;
179 if (!submodule)
180 submodule = "";
181 len = strlen(submodule) + 1;
182 refs = xcalloc(1, sizeof(struct ref_cache) + len);
183 memcpy(refs->name, submodule, len);
184 return refs;
188 * Return a pointer to a ref_cache for the specified submodule. For
189 * the main repository, use submodule==NULL. The returned structure
190 * will be allocated and initialized but not necessarily populated; it
191 * should not be freed.
193 static struct ref_cache *get_ref_cache(const char *submodule)
195 struct ref_cache *refs = ref_cache;
196 if (!submodule)
197 submodule = "";
198 while (refs) {
199 if (!strcmp(submodule, refs->name))
200 return refs;
201 refs = refs->next;
204 refs = create_ref_cache(submodule);
205 refs->next = ref_cache;
206 ref_cache = refs;
207 return refs;
210 void invalidate_ref_cache(const char *submodule)
212 struct ref_cache *refs = get_ref_cache(submodule);
213 clear_packed_ref_cache(refs);
214 clear_loose_ref_cache(refs);
217 static void read_packed_refs(FILE *f, struct ref_array *array)
219 struct ref_entry *last = NULL;
220 char refline[PATH_MAX];
221 int flag = REF_ISPACKED;
223 while (fgets(refline, sizeof(refline), f)) {
224 unsigned char sha1[20];
225 const char *name;
226 static const char header[] = "# pack-refs with:";
228 if (!strncmp(refline, header, sizeof(header)-1)) {
229 const char *traits = refline + sizeof(header) - 1;
230 if (strstr(traits, " peeled "))
231 flag |= REF_KNOWS_PEELED;
232 /* perhaps other traits later as well */
233 continue;
236 name = parse_ref_line(refline, sha1);
237 if (name) {
238 add_ref(name, sha1, flag, array, &last);
239 continue;
241 if (last &&
242 refline[0] == '^' &&
243 strlen(refline) == 42 &&
244 refline[41] == '\n' &&
245 !get_sha1_hex(refline + 1, sha1))
246 hashcpy(last->peeled, sha1);
248 sort_ref_array(array);
251 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
253 add_ref(name, sha1, flag, &extra_refs, NULL);
256 void clear_extra_refs(void)
258 free_ref_array(&extra_refs);
261 static struct ref_array *get_packed_refs(const char *submodule)
263 struct ref_cache *refs = get_ref_cache(submodule);
265 if (!refs->did_packed) {
266 const char *packed_refs_file;
267 FILE *f;
269 if (submodule)
270 packed_refs_file = git_path_submodule(submodule, "packed-refs");
271 else
272 packed_refs_file = git_path("packed-refs");
273 f = fopen(packed_refs_file, "r");
274 if (f) {
275 read_packed_refs(f, &refs->packed);
276 fclose(f);
278 refs->did_packed = 1;
280 return &refs->packed;
283 static void get_ref_dir(const char *submodule, const char *base,
284 struct ref_array *array)
286 DIR *dir;
287 const char *path;
289 if (submodule)
290 path = git_path_submodule(submodule, "%s", base);
291 else
292 path = git_path("%s", base);
295 dir = opendir(path);
297 if (dir) {
298 struct dirent *de;
299 int baselen = strlen(base);
300 char *ref = xmalloc(baselen + 257);
302 memcpy(ref, base, baselen);
303 if (baselen && base[baselen-1] != '/')
304 ref[baselen++] = '/';
306 while ((de = readdir(dir)) != NULL) {
307 unsigned char sha1[20];
308 struct stat st;
309 int flag;
310 int namelen;
311 const char *refdir;
313 if (de->d_name[0] == '.')
314 continue;
315 namelen = strlen(de->d_name);
316 if (namelen > 255)
317 continue;
318 if (has_extension(de->d_name, ".lock"))
319 continue;
320 memcpy(ref + baselen, de->d_name, namelen+1);
321 refdir = submodule
322 ? git_path_submodule(submodule, "%s", ref)
323 : git_path("%s", ref);
324 if (stat(refdir, &st) < 0)
325 continue;
326 if (S_ISDIR(st.st_mode)) {
327 get_ref_dir(submodule, ref, array);
328 continue;
330 if (submodule) {
331 hashclr(sha1);
332 flag = 0;
333 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
334 hashclr(sha1);
335 flag |= REF_BROKEN;
337 } else
338 if (!resolve_ref(ref, sha1, 1, &flag)) {
339 hashclr(sha1);
340 flag |= REF_BROKEN;
342 add_ref(ref, sha1, flag, array, NULL);
344 free(ref);
345 closedir(dir);
349 struct warn_if_dangling_data {
350 FILE *fp;
351 const char *refname;
352 const char *msg_fmt;
355 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
356 int flags, void *cb_data)
358 struct warn_if_dangling_data *d = cb_data;
359 const char *resolves_to;
360 unsigned char junk[20];
362 if (!(flags & REF_ISSYMREF))
363 return 0;
365 resolves_to = resolve_ref(refname, junk, 0, NULL);
366 if (!resolves_to || strcmp(resolves_to, d->refname))
367 return 0;
369 fprintf(d->fp, d->msg_fmt, refname);
370 return 0;
373 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
375 struct warn_if_dangling_data data;
377 data.fp = fp;
378 data.refname = refname;
379 data.msg_fmt = msg_fmt;
380 for_each_rawref(warn_if_dangling_symref, &data);
383 static struct ref_array *get_loose_refs(const char *submodule)
385 struct ref_cache *refs = get_ref_cache(submodule);
387 if (!refs->did_loose) {
388 get_ref_dir(submodule, "refs", &refs->loose);
389 sort_ref_array(&refs->loose);
390 refs->did_loose = 1;
392 return &refs->loose;
395 /* We allow "recursive" symbolic refs. Only within reason, though */
396 #define MAXDEPTH 5
397 #define MAXREFLEN (1024)
399 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
401 int retval = -1;
402 struct ref_entry *ref;
403 struct ref_array *array = get_packed_refs(name);
405 ref = search_ref_array(array, refname);
406 if (ref != NULL) {
407 memcpy(result, ref->sha1, 20);
408 retval = 0;
410 return retval;
413 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
415 int fd, len = strlen(refname);
416 char buffer[128], *p;
418 if (recursion > MAXDEPTH || len > MAXREFLEN)
419 return -1;
420 memcpy(name + pathlen, refname, len+1);
421 fd = open(name, O_RDONLY);
422 if (fd < 0)
423 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
425 len = read(fd, buffer, sizeof(buffer)-1);
426 close(fd);
427 if (len < 0)
428 return -1;
429 while (len && isspace(buffer[len-1]))
430 len--;
431 buffer[len] = 0;
433 /* Was it a detached head or an old-fashioned symlink? */
434 if (!get_sha1_hex(buffer, result))
435 return 0;
437 /* Symref? */
438 if (strncmp(buffer, "ref:", 4))
439 return -1;
440 p = buffer + 4;
441 while (isspace(*p))
442 p++;
444 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
447 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
449 int len = strlen(path), retval;
450 char *gitdir;
451 const char *tmp;
453 while (len && path[len-1] == '/')
454 len--;
455 if (!len)
456 return -1;
457 gitdir = xmalloc(len + MAXREFLEN + 8);
458 memcpy(gitdir, path, len);
459 memcpy(gitdir + len, "/.git", 6);
460 len += 5;
462 tmp = read_gitfile(gitdir);
463 if (tmp) {
464 free(gitdir);
465 len = strlen(tmp);
466 gitdir = xmalloc(len + MAXREFLEN + 3);
467 memcpy(gitdir, tmp, len);
469 gitdir[len] = '/';
470 gitdir[++len] = '\0';
471 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
472 free(gitdir);
473 return retval;
477 * Try to read ref from the packed references. On success, set sha1
478 * and return 0; otherwise, return -1.
480 static int get_packed_ref(const char *ref, unsigned char *sha1)
482 struct ref_array *packed = get_packed_refs(NULL);
483 struct ref_entry *entry = search_ref_array(packed, ref);
484 if (entry) {
485 hashcpy(sha1, entry->sha1);
486 return 0;
488 return -1;
491 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
493 int depth = MAXDEPTH;
494 ssize_t len;
495 char buffer[256];
496 static char ref_buffer[256];
497 char path[PATH_MAX];
499 if (flag)
500 *flag = 0;
502 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
503 return NULL;
505 for (;;) {
506 struct stat st;
507 char *buf;
508 int fd;
510 if (--depth < 0)
511 return NULL;
513 git_snpath(path, sizeof(path), "%s", ref);
515 if (lstat(path, &st) < 0) {
516 if (errno != ENOENT)
517 return NULL;
519 * The loose reference file does not exist;
520 * check for a packed reference.
522 if (!get_packed_ref(ref, sha1)) {
523 if (flag)
524 *flag |= REF_ISPACKED;
525 return ref;
527 /* The reference is not a packed reference, either. */
528 if (reading) {
529 return NULL;
530 } else {
531 hashclr(sha1);
532 return ref;
536 /* Follow "normalized" - ie "refs/.." symlinks by hand */
537 if (S_ISLNK(st.st_mode)) {
538 len = readlink(path, buffer, sizeof(buffer)-1);
539 if (len < 0)
540 return NULL;
541 buffer[len] = 0;
542 if (!prefixcmp(buffer, "refs/") &&
543 !check_refname_format(buffer, 0)) {
544 strcpy(ref_buffer, buffer);
545 ref = ref_buffer;
546 if (flag)
547 *flag |= REF_ISSYMREF;
548 continue;
552 /* Is it a directory? */
553 if (S_ISDIR(st.st_mode)) {
554 errno = EISDIR;
555 return NULL;
559 * Anything else, just open it and try to use it as
560 * a ref
562 fd = open(path, O_RDONLY);
563 if (fd < 0)
564 return NULL;
565 len = read_in_full(fd, buffer, sizeof(buffer)-1);
566 close(fd);
567 if (len < 0)
568 return NULL;
569 while (len && isspace(buffer[len-1]))
570 len--;
571 buffer[len] = '\0';
574 * Is it a symbolic ref?
576 if (prefixcmp(buffer, "ref:"))
577 break;
578 buf = buffer + 4;
579 while (isspace(*buf))
580 buf++;
581 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
582 warning("symbolic reference in %s is formatted incorrectly",
583 path);
584 return NULL;
586 ref = strcpy(ref_buffer, buf);
587 if (flag)
588 *flag |= REF_ISSYMREF;
590 /* Please note that FETCH_HEAD has a second line containing other data. */
591 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
592 warning("reference in %s is formatted incorrectly", path);
593 return NULL;
595 return ref;
598 /* The argument to filter_refs */
599 struct ref_filter {
600 const char *pattern;
601 each_ref_fn *fn;
602 void *cb_data;
605 int read_ref(const char *ref, unsigned char *sha1)
607 if (resolve_ref(ref, sha1, 1, NULL))
608 return 0;
609 return -1;
612 #define DO_FOR_EACH_INCLUDE_BROKEN 01
613 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
614 int flags, void *cb_data, struct ref_entry *entry)
616 if (prefixcmp(entry->name, base))
617 return 0;
619 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
620 if (entry->flag & REF_BROKEN)
621 return 0; /* ignore dangling symref */
622 if (!has_sha1_file(entry->sha1)) {
623 error("%s does not point to a valid object!", entry->name);
624 return 0;
627 current_ref = entry;
628 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
631 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
632 void *data)
634 struct ref_filter *filter = (struct ref_filter *)data;
635 if (fnmatch(filter->pattern, ref, 0))
636 return 0;
637 return filter->fn(ref, sha, flags, filter->cb_data);
640 int peel_ref(const char *ref, unsigned char *sha1)
642 int flag;
643 unsigned char base[20];
644 struct object *o;
646 if (current_ref && (current_ref->name == ref
647 || !strcmp(current_ref->name, ref))) {
648 if (current_ref->flag & REF_KNOWS_PEELED) {
649 hashcpy(sha1, current_ref->peeled);
650 return 0;
652 hashcpy(base, current_ref->sha1);
653 goto fallback;
656 if (!resolve_ref(ref, base, 1, &flag))
657 return -1;
659 if ((flag & REF_ISPACKED)) {
660 struct ref_array *array = get_packed_refs(NULL);
661 struct ref_entry *r = search_ref_array(array, ref);
663 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
664 hashcpy(sha1, r->peeled);
665 return 0;
669 fallback:
670 o = parse_object(base);
671 if (o && o->type == OBJ_TAG) {
672 o = deref_tag(o, ref, 0);
673 if (o) {
674 hashcpy(sha1, o->sha1);
675 return 0;
678 return -1;
681 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
682 int trim, int flags, void *cb_data)
684 int retval = 0, i, p = 0, l = 0;
685 struct ref_array *packed = get_packed_refs(submodule);
686 struct ref_array *loose = get_loose_refs(submodule);
688 struct ref_array *extra = &extra_refs;
690 for (i = 0; i < extra->nr; i++)
691 retval = do_one_ref(base, fn, trim, flags, cb_data, extra->refs[i]);
693 while (p < packed->nr && l < loose->nr) {
694 struct ref_entry *entry;
695 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
696 if (!cmp) {
697 p++;
698 continue;
700 if (cmp > 0) {
701 entry = loose->refs[l++];
702 } else {
703 entry = packed->refs[p++];
705 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
706 if (retval)
707 goto end_each;
710 if (l < loose->nr) {
711 p = l;
712 packed = loose;
715 for (; p < packed->nr; p++) {
716 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
717 if (retval)
718 goto end_each;
721 end_each:
722 current_ref = NULL;
723 return retval;
727 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
729 unsigned char sha1[20];
730 int flag;
732 if (submodule) {
733 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
734 return fn("HEAD", sha1, 0, cb_data);
736 return 0;
739 if (resolve_ref("HEAD", sha1, 1, &flag))
740 return fn("HEAD", sha1, flag, cb_data);
742 return 0;
745 int head_ref(each_ref_fn fn, void *cb_data)
747 return do_head_ref(NULL, fn, cb_data);
750 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
752 return do_head_ref(submodule, fn, cb_data);
755 int for_each_ref(each_ref_fn fn, void *cb_data)
757 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
760 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
762 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
765 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
767 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
770 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
771 each_ref_fn fn, void *cb_data)
773 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
776 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
778 return for_each_ref_in("refs/tags/", fn, cb_data);
781 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
783 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
786 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
788 return for_each_ref_in("refs/heads/", fn, cb_data);
791 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
793 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
796 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
798 return for_each_ref_in("refs/remotes/", fn, cb_data);
801 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
803 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
806 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
808 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
811 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
813 struct strbuf buf = STRBUF_INIT;
814 int ret = 0;
815 unsigned char sha1[20];
816 int flag;
818 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
819 if (resolve_ref(buf.buf, sha1, 1, &flag))
820 ret = fn(buf.buf, sha1, flag, cb_data);
821 strbuf_release(&buf);
823 return ret;
826 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
828 struct strbuf buf = STRBUF_INIT;
829 int ret;
830 strbuf_addf(&buf, "%srefs/", get_git_namespace());
831 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
832 strbuf_release(&buf);
833 return ret;
836 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
837 const char *prefix, void *cb_data)
839 struct strbuf real_pattern = STRBUF_INIT;
840 struct ref_filter filter;
841 int ret;
843 if (!prefix && prefixcmp(pattern, "refs/"))
844 strbuf_addstr(&real_pattern, "refs/");
845 else if (prefix)
846 strbuf_addstr(&real_pattern, prefix);
847 strbuf_addstr(&real_pattern, pattern);
849 if (!has_glob_specials(pattern)) {
850 /* Append implied '/' '*' if not present. */
851 if (real_pattern.buf[real_pattern.len - 1] != '/')
852 strbuf_addch(&real_pattern, '/');
853 /* No need to check for '*', there is none. */
854 strbuf_addch(&real_pattern, '*');
857 filter.pattern = real_pattern.buf;
858 filter.fn = fn;
859 filter.cb_data = cb_data;
860 ret = for_each_ref(filter_refs, &filter);
862 strbuf_release(&real_pattern);
863 return ret;
866 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
868 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
871 int for_each_rawref(each_ref_fn fn, void *cb_data)
873 return do_for_each_ref(NULL, "", fn, 0,
874 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
878 * Make sure "ref" is something reasonable to have under ".git/refs/";
879 * We do not like it if:
881 * - any path component of it begins with ".", or
882 * - it has double dots "..", or
883 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
884 * - it ends with a "/".
885 * - it ends with ".lock"
886 * - it contains a "\" (backslash)
889 /* Return true iff ch is not allowed in reference names. */
890 static inline int bad_ref_char(int ch)
892 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
893 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
894 return 1;
895 /* 2.13 Pattern Matching Notation */
896 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
897 return 1;
898 return 0;
902 * Try to read one refname component from the front of ref. Return
903 * the length of the component found, or -1 if the component is not
904 * legal.
906 static int check_refname_component(const char *ref, int flags)
908 const char *cp;
909 char last = '\0';
911 for (cp = ref; ; cp++) {
912 char ch = *cp;
913 if (ch == '\0' || ch == '/')
914 break;
915 if (bad_ref_char(ch))
916 return -1; /* Illegal character in refname. */
917 if (last == '.' && ch == '.')
918 return -1; /* Refname contains "..". */
919 if (last == '@' && ch == '{')
920 return -1; /* Refname contains "@{". */
921 last = ch;
923 if (cp == ref)
924 return -1; /* Component has zero length. */
925 if (ref[0] == '.') {
926 if (!(flags & REFNAME_DOT_COMPONENT))
927 return -1; /* Component starts with '.'. */
929 * Even if leading dots are allowed, don't allow "."
930 * as a component (".." is prevented by a rule above).
932 if (ref[1] == '\0')
933 return -1; /* Component equals ".". */
935 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
936 return -1; /* Refname ends with ".lock". */
937 return cp - ref;
940 int check_refname_format(const char *ref, int flags)
942 int component_len, component_count = 0;
944 while (1) {
945 /* We are at the start of a path component. */
946 component_len = check_refname_component(ref, flags);
947 if (component_len < 0) {
948 if ((flags & REFNAME_REFSPEC_PATTERN) &&
949 ref[0] == '*' &&
950 (ref[1] == '\0' || ref[1] == '/')) {
951 /* Accept one wildcard as a full refname component. */
952 flags &= ~REFNAME_REFSPEC_PATTERN;
953 component_len = 1;
954 } else {
955 return -1;
958 component_count++;
959 if (ref[component_len] == '\0')
960 break;
961 /* Skip to next component. */
962 ref += component_len + 1;
965 if (ref[component_len - 1] == '.')
966 return -1; /* Refname ends with '.'. */
967 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
968 return -1; /* Refname has only one component. */
969 return 0;
972 const char *prettify_refname(const char *name)
974 return name + (
975 !prefixcmp(name, "refs/heads/") ? 11 :
976 !prefixcmp(name, "refs/tags/") ? 10 :
977 !prefixcmp(name, "refs/remotes/") ? 13 :
981 const char *ref_rev_parse_rules[] = {
982 "%.*s",
983 "refs/%.*s",
984 "refs/tags/%.*s",
985 "refs/heads/%.*s",
986 "refs/remotes/%.*s",
987 "refs/remotes/%.*s/HEAD",
988 NULL
991 const char *ref_fetch_rules[] = {
992 "%.*s",
993 "refs/%.*s",
994 "refs/heads/%.*s",
995 NULL
998 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1000 const char **p;
1001 const int abbrev_name_len = strlen(abbrev_name);
1003 for (p = rules; *p; p++) {
1004 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1005 return 1;
1009 return 0;
1012 static struct ref_lock *verify_lock(struct ref_lock *lock,
1013 const unsigned char *old_sha1, int mustexist)
1015 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1016 error("Can't verify ref %s", lock->ref_name);
1017 unlock_ref(lock);
1018 return NULL;
1020 if (hashcmp(lock->old_sha1, old_sha1)) {
1021 error("Ref %s is at %s but expected %s", lock->ref_name,
1022 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1023 unlock_ref(lock);
1024 return NULL;
1026 return lock;
1029 static int remove_empty_directories(const char *file)
1031 /* we want to create a file but there is a directory there;
1032 * if that is an empty directory (or a directory that contains
1033 * only empty directories), remove them.
1035 struct strbuf path;
1036 int result;
1038 strbuf_init(&path, 20);
1039 strbuf_addstr(&path, file);
1041 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1043 strbuf_release(&path);
1045 return result;
1048 static int is_refname_available(const char *ref, const char *oldref,
1049 struct ref_array *array, int quiet)
1051 int i, namlen = strlen(ref); /* e.g. 'foo/bar' */
1052 for (i = 0; i < array->nr; i++ ) {
1053 struct ref_entry *entry = array->refs[i];
1054 /* entry->name could be 'foo' or 'foo/bar/baz' */
1055 if (!oldref || strcmp(oldref, entry->name)) {
1056 int len = strlen(entry->name);
1057 int cmplen = (namlen < len) ? namlen : len;
1058 const char *lead = (namlen < len) ? entry->name : ref;
1059 if (!strncmp(ref, entry->name, cmplen) &&
1060 lead[cmplen] == '/') {
1061 if (!quiet)
1062 error("'%s' exists; cannot create '%s'",
1063 entry->name, ref);
1064 return 0;
1068 return 1;
1071 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1073 char *ref_file;
1074 const char *orig_ref = ref;
1075 struct ref_lock *lock;
1076 int last_errno = 0;
1077 int type, lflags;
1078 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1079 int missing = 0;
1081 lock = xcalloc(1, sizeof(struct ref_lock));
1082 lock->lock_fd = -1;
1084 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1085 if (!ref && errno == EISDIR) {
1086 /* we are trying to lock foo but we used to
1087 * have foo/bar which now does not exist;
1088 * it is normal for the empty directory 'foo'
1089 * to remain.
1091 ref_file = git_path("%s", orig_ref);
1092 if (remove_empty_directories(ref_file)) {
1093 last_errno = errno;
1094 error("there are still refs under '%s'", orig_ref);
1095 goto error_return;
1097 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1099 if (type_p)
1100 *type_p = type;
1101 if (!ref) {
1102 last_errno = errno;
1103 error("unable to resolve reference %s: %s",
1104 orig_ref, strerror(errno));
1105 goto error_return;
1107 missing = is_null_sha1(lock->old_sha1);
1108 /* When the ref did not exist and we are creating it,
1109 * make sure there is no existing ref that is packed
1110 * whose name begins with our refname, nor a ref whose
1111 * name is a proper prefix of our refname.
1113 if (missing &&
1114 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1115 last_errno = ENOTDIR;
1116 goto error_return;
1119 lock->lk = xcalloc(1, sizeof(struct lock_file));
1121 lflags = LOCK_DIE_ON_ERROR;
1122 if (flags & REF_NODEREF) {
1123 ref = orig_ref;
1124 lflags |= LOCK_NODEREF;
1126 lock->ref_name = xstrdup(ref);
1127 lock->orig_ref_name = xstrdup(orig_ref);
1128 ref_file = git_path("%s", ref);
1129 if (missing)
1130 lock->force_write = 1;
1131 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1132 lock->force_write = 1;
1134 if (safe_create_leading_directories(ref_file)) {
1135 last_errno = errno;
1136 error("unable to create directory for %s", ref_file);
1137 goto error_return;
1140 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1141 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1143 error_return:
1144 unlock_ref(lock);
1145 errno = last_errno;
1146 return NULL;
1149 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1151 char refpath[PATH_MAX];
1152 if (check_refname_format(ref, 0))
1153 return NULL;
1154 strcpy(refpath, mkpath("refs/%s", ref));
1155 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1158 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1160 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1161 return NULL;
1162 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1165 static struct lock_file packlock;
1167 static int repack_without_ref(const char *refname)
1169 struct ref_array *packed;
1170 struct ref_entry *ref;
1171 int fd, i;
1173 packed = get_packed_refs(NULL);
1174 ref = search_ref_array(packed, refname);
1175 if (ref == NULL)
1176 return 0;
1177 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1178 if (fd < 0) {
1179 unable_to_lock_error(git_path("packed-refs"), errno);
1180 return error("cannot delete '%s' from packed refs", refname);
1183 for (i = 0; i < packed->nr; i++) {
1184 char line[PATH_MAX + 100];
1185 int len;
1187 ref = packed->refs[i];
1189 if (!strcmp(refname, ref->name))
1190 continue;
1191 len = snprintf(line, sizeof(line), "%s %s\n",
1192 sha1_to_hex(ref->sha1), ref->name);
1193 /* this should not happen but just being defensive */
1194 if (len > sizeof(line))
1195 die("too long a refname '%s'", ref->name);
1196 write_or_die(fd, line, len);
1198 return commit_lock_file(&packlock);
1201 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1203 struct ref_lock *lock;
1204 int err, i = 0, ret = 0, flag = 0;
1206 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1207 if (!lock)
1208 return 1;
1209 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1210 /* loose */
1211 const char *path;
1213 if (!(delopt & REF_NODEREF)) {
1214 i = strlen(lock->lk->filename) - 5; /* .lock */
1215 lock->lk->filename[i] = 0;
1216 path = lock->lk->filename;
1217 } else {
1218 path = git_path("%s", refname);
1220 err = unlink_or_warn(path);
1221 if (err && errno != ENOENT)
1222 ret = 1;
1224 if (!(delopt & REF_NODEREF))
1225 lock->lk->filename[i] = '.';
1227 /* removing the loose one could have resurrected an earlier
1228 * packed one. Also, if it was not loose we need to repack
1229 * without it.
1231 ret |= repack_without_ref(refname);
1233 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1234 invalidate_ref_cache(NULL);
1235 unlock_ref(lock);
1236 return ret;
1240 * People using contrib's git-new-workdir have .git/logs/refs ->
1241 * /some/other/path/.git/logs/refs, and that may live on another device.
1243 * IOW, to avoid cross device rename errors, the temporary renamed log must
1244 * live into logs/refs.
1246 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1248 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1250 static const char renamed_ref[] = "RENAMED-REF";
1251 unsigned char sha1[20], orig_sha1[20];
1252 int flag = 0, logmoved = 0;
1253 struct ref_lock *lock;
1254 struct stat loginfo;
1255 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1256 const char *symref = NULL;
1258 if (log && S_ISLNK(loginfo.st_mode))
1259 return error("reflog for %s is a symlink", oldref);
1261 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1262 if (flag & REF_ISSYMREF)
1263 return error("refname %s is a symbolic ref, renaming it is not supported",
1264 oldref);
1265 if (!symref)
1266 return error("refname %s not found", oldref);
1268 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1269 return 1;
1271 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1272 return 1;
1274 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1275 if (!lock)
1276 return error("unable to lock %s", renamed_ref);
1277 lock->force_write = 1;
1278 if (write_ref_sha1(lock, orig_sha1, logmsg))
1279 return error("unable to save current sha1 in %s", renamed_ref);
1281 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1282 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1283 oldref, strerror(errno));
1285 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1286 error("unable to delete old %s", oldref);
1287 goto rollback;
1290 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1291 if (errno==EISDIR) {
1292 if (remove_empty_directories(git_path("%s", newref))) {
1293 error("Directory not empty: %s", newref);
1294 goto rollback;
1296 } else {
1297 error("unable to delete existing %s", newref);
1298 goto rollback;
1302 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1303 error("unable to create directory for %s", newref);
1304 goto rollback;
1307 retry:
1308 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1309 if (errno==EISDIR || errno==ENOTDIR) {
1311 * rename(a, b) when b is an existing
1312 * directory ought to result in ISDIR, but
1313 * Solaris 5.8 gives ENOTDIR. Sheesh.
1315 if (remove_empty_directories(git_path("logs/%s", newref))) {
1316 error("Directory not empty: logs/%s", newref);
1317 goto rollback;
1319 goto retry;
1320 } else {
1321 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1322 newref, strerror(errno));
1323 goto rollback;
1326 logmoved = log;
1328 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1329 if (!lock) {
1330 error("unable to lock %s for update", newref);
1331 goto rollback;
1333 lock->force_write = 1;
1334 hashcpy(lock->old_sha1, orig_sha1);
1335 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1336 error("unable to write current sha1 into %s", newref);
1337 goto rollback;
1340 return 0;
1342 rollback:
1343 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1344 if (!lock) {
1345 error("unable to lock %s for rollback", oldref);
1346 goto rollbacklog;
1349 lock->force_write = 1;
1350 flag = log_all_ref_updates;
1351 log_all_ref_updates = 0;
1352 if (write_ref_sha1(lock, orig_sha1, NULL))
1353 error("unable to write current sha1 into %s", oldref);
1354 log_all_ref_updates = flag;
1356 rollbacklog:
1357 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1358 error("unable to restore logfile %s from %s: %s",
1359 oldref, newref, strerror(errno));
1360 if (!logmoved && log &&
1361 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1362 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1363 oldref, strerror(errno));
1365 return 1;
1368 int close_ref(struct ref_lock *lock)
1370 if (close_lock_file(lock->lk))
1371 return -1;
1372 lock->lock_fd = -1;
1373 return 0;
1376 int commit_ref(struct ref_lock *lock)
1378 if (commit_lock_file(lock->lk))
1379 return -1;
1380 lock->lock_fd = -1;
1381 return 0;
1384 void unlock_ref(struct ref_lock *lock)
1386 /* Do not free lock->lk -- atexit() still looks at them */
1387 if (lock->lk)
1388 rollback_lock_file(lock->lk);
1389 free(lock->ref_name);
1390 free(lock->orig_ref_name);
1391 free(lock);
1395 * copy the reflog message msg to buf, which has been allocated sufficiently
1396 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1397 * because reflog file is one line per entry.
1399 static int copy_msg(char *buf, const char *msg)
1401 char *cp = buf;
1402 char c;
1403 int wasspace = 1;
1405 *cp++ = '\t';
1406 while ((c = *msg++)) {
1407 if (wasspace && isspace(c))
1408 continue;
1409 wasspace = isspace(c);
1410 if (wasspace)
1411 c = ' ';
1412 *cp++ = c;
1414 while (buf < cp && isspace(cp[-1]))
1415 cp--;
1416 *cp++ = '\n';
1417 return cp - buf;
1420 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1422 int logfd, oflags = O_APPEND | O_WRONLY;
1424 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1425 if (log_all_ref_updates &&
1426 (!prefixcmp(ref_name, "refs/heads/") ||
1427 !prefixcmp(ref_name, "refs/remotes/") ||
1428 !prefixcmp(ref_name, "refs/notes/") ||
1429 !strcmp(ref_name, "HEAD"))) {
1430 if (safe_create_leading_directories(logfile) < 0)
1431 return error("unable to create directory for %s",
1432 logfile);
1433 oflags |= O_CREAT;
1436 logfd = open(logfile, oflags, 0666);
1437 if (logfd < 0) {
1438 if (!(oflags & O_CREAT) && errno == ENOENT)
1439 return 0;
1441 if ((oflags & O_CREAT) && errno == EISDIR) {
1442 if (remove_empty_directories(logfile)) {
1443 return error("There are still logs under '%s'",
1444 logfile);
1446 logfd = open(logfile, oflags, 0666);
1449 if (logfd < 0)
1450 return error("Unable to append to %s: %s",
1451 logfile, strerror(errno));
1454 adjust_shared_perm(logfile);
1455 close(logfd);
1456 return 0;
1459 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1460 const unsigned char *new_sha1, const char *msg)
1462 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1463 unsigned maxlen, len;
1464 int msglen;
1465 char log_file[PATH_MAX];
1466 char *logrec;
1467 const char *committer;
1469 if (log_all_ref_updates < 0)
1470 log_all_ref_updates = !is_bare_repository();
1472 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1473 if (result)
1474 return result;
1476 logfd = open(log_file, oflags);
1477 if (logfd < 0)
1478 return 0;
1479 msglen = msg ? strlen(msg) : 0;
1480 committer = git_committer_info(0);
1481 maxlen = strlen(committer) + msglen + 100;
1482 logrec = xmalloc(maxlen);
1483 len = sprintf(logrec, "%s %s %s\n",
1484 sha1_to_hex(old_sha1),
1485 sha1_to_hex(new_sha1),
1486 committer);
1487 if (msglen)
1488 len += copy_msg(logrec + len - 1, msg) - 1;
1489 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1490 free(logrec);
1491 if (close(logfd) != 0 || written != len)
1492 return error("Unable to append to %s", log_file);
1493 return 0;
1496 static int is_branch(const char *refname)
1498 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1501 int write_ref_sha1(struct ref_lock *lock,
1502 const unsigned char *sha1, const char *logmsg)
1504 static char term = '\n';
1505 struct object *o;
1507 if (!lock)
1508 return -1;
1509 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1510 unlock_ref(lock);
1511 return 0;
1513 o = parse_object(sha1);
1514 if (!o) {
1515 error("Trying to write ref %s with nonexistent object %s",
1516 lock->ref_name, sha1_to_hex(sha1));
1517 unlock_ref(lock);
1518 return -1;
1520 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1521 error("Trying to write non-commit object %s to branch %s",
1522 sha1_to_hex(sha1), lock->ref_name);
1523 unlock_ref(lock);
1524 return -1;
1526 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1527 write_in_full(lock->lock_fd, &term, 1) != 1
1528 || close_ref(lock) < 0) {
1529 error("Couldn't write %s", lock->lk->filename);
1530 unlock_ref(lock);
1531 return -1;
1533 clear_loose_ref_cache(get_ref_cache(NULL));
1534 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1535 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1536 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1537 unlock_ref(lock);
1538 return -1;
1540 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1542 * Special hack: If a branch is updated directly and HEAD
1543 * points to it (may happen on the remote side of a push
1544 * for example) then logically the HEAD reflog should be
1545 * updated too.
1546 * A generic solution implies reverse symref information,
1547 * but finding all symrefs pointing to the given branch
1548 * would be rather costly for this rare event (the direct
1549 * update of a branch) to be worth it. So let's cheat and
1550 * check with HEAD only which should cover 99% of all usage
1551 * scenarios (even 100% of the default ones).
1553 unsigned char head_sha1[20];
1554 int head_flag;
1555 const char *head_ref;
1556 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1557 if (head_ref && (head_flag & REF_ISSYMREF) &&
1558 !strcmp(head_ref, lock->ref_name))
1559 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1561 if (commit_ref(lock)) {
1562 error("Couldn't set %s", lock->ref_name);
1563 unlock_ref(lock);
1564 return -1;
1566 unlock_ref(lock);
1567 return 0;
1570 int create_symref(const char *ref_target, const char *refs_heads_master,
1571 const char *logmsg)
1573 const char *lockpath;
1574 char ref[1000];
1575 int fd, len, written;
1576 char *git_HEAD = git_pathdup("%s", ref_target);
1577 unsigned char old_sha1[20], new_sha1[20];
1579 if (logmsg && read_ref(ref_target, old_sha1))
1580 hashclr(old_sha1);
1582 if (safe_create_leading_directories(git_HEAD) < 0)
1583 return error("unable to create directory for %s", git_HEAD);
1585 #ifndef NO_SYMLINK_HEAD
1586 if (prefer_symlink_refs) {
1587 unlink(git_HEAD);
1588 if (!symlink(refs_heads_master, git_HEAD))
1589 goto done;
1590 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1592 #endif
1594 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1595 if (sizeof(ref) <= len) {
1596 error("refname too long: %s", refs_heads_master);
1597 goto error_free_return;
1599 lockpath = mkpath("%s.lock", git_HEAD);
1600 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1601 if (fd < 0) {
1602 error("Unable to open %s for writing", lockpath);
1603 goto error_free_return;
1605 written = write_in_full(fd, ref, len);
1606 if (close(fd) != 0 || written != len) {
1607 error("Unable to write to %s", lockpath);
1608 goto error_unlink_return;
1610 if (rename(lockpath, git_HEAD) < 0) {
1611 error("Unable to create %s", git_HEAD);
1612 goto error_unlink_return;
1614 if (adjust_shared_perm(git_HEAD)) {
1615 error("Unable to fix permissions on %s", lockpath);
1616 error_unlink_return:
1617 unlink_or_warn(lockpath);
1618 error_free_return:
1619 free(git_HEAD);
1620 return -1;
1623 #ifndef NO_SYMLINK_HEAD
1624 done:
1625 #endif
1626 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1627 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1629 free(git_HEAD);
1630 return 0;
1633 static char *ref_msg(const char *line, const char *endp)
1635 const char *ep;
1636 line += 82;
1637 ep = memchr(line, '\n', endp - line);
1638 if (!ep)
1639 ep = endp;
1640 return xmemdupz(line, ep - line);
1643 int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *sha1, char **msg, unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1645 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1646 char *tz_c;
1647 int logfd, tz, reccnt = 0;
1648 struct stat st;
1649 unsigned long date;
1650 unsigned char logged_sha1[20];
1651 void *log_mapped;
1652 size_t mapsz;
1654 logfile = git_path("logs/%s", ref);
1655 logfd = open(logfile, O_RDONLY, 0);
1656 if (logfd < 0)
1657 die_errno("Unable to read log '%s'", logfile);
1658 fstat(logfd, &st);
1659 if (!st.st_size)
1660 die("Log %s is empty.", logfile);
1661 mapsz = xsize_t(st.st_size);
1662 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1663 logdata = log_mapped;
1664 close(logfd);
1666 lastrec = NULL;
1667 rec = logend = logdata + st.st_size;
1668 while (logdata < rec) {
1669 reccnt++;
1670 if (logdata < rec && *(rec-1) == '\n')
1671 rec--;
1672 lastgt = NULL;
1673 while (logdata < rec && *(rec-1) != '\n') {
1674 rec--;
1675 if (*rec == '>')
1676 lastgt = rec;
1678 if (!lastgt)
1679 die("Log %s is corrupt.", logfile);
1680 date = strtoul(lastgt + 1, &tz_c, 10);
1681 if (date <= at_time || cnt == 0) {
1682 tz = strtoul(tz_c, NULL, 10);
1683 if (msg)
1684 *msg = ref_msg(rec, logend);
1685 if (cutoff_time)
1686 *cutoff_time = date;
1687 if (cutoff_tz)
1688 *cutoff_tz = tz;
1689 if (cutoff_cnt)
1690 *cutoff_cnt = reccnt - 1;
1691 if (lastrec) {
1692 if (get_sha1_hex(lastrec, logged_sha1))
1693 die("Log %s is corrupt.", logfile);
1694 if (get_sha1_hex(rec + 41, sha1))
1695 die("Log %s is corrupt.", logfile);
1696 if (hashcmp(logged_sha1, sha1)) {
1697 warning("Log %s has gap after %s.",
1698 logfile, show_date(date, tz, DATE_RFC2822));
1701 else if (date == at_time) {
1702 if (get_sha1_hex(rec + 41, sha1))
1703 die("Log %s is corrupt.", logfile);
1705 else {
1706 if (get_sha1_hex(rec + 41, logged_sha1))
1707 die("Log %s is corrupt.", logfile);
1708 if (hashcmp(logged_sha1, sha1)) {
1709 warning("Log %s unexpectedly ended on %s.",
1710 logfile, show_date(date, tz, DATE_RFC2822));
1713 munmap(log_mapped, mapsz);
1714 return 0;
1716 lastrec = rec;
1717 if (cnt > 0)
1718 cnt--;
1721 rec = logdata;
1722 while (rec < logend && *rec != '>' && *rec != '\n')
1723 rec++;
1724 if (rec == logend || *rec == '\n')
1725 die("Log %s is corrupt.", logfile);
1726 date = strtoul(rec + 1, &tz_c, 10);
1727 tz = strtoul(tz_c, NULL, 10);
1728 if (get_sha1_hex(logdata, sha1))
1729 die("Log %s is corrupt.", logfile);
1730 if (is_null_sha1(sha1)) {
1731 if (get_sha1_hex(logdata + 41, sha1))
1732 die("Log %s is corrupt.", logfile);
1734 if (msg)
1735 *msg = ref_msg(logdata, logend);
1736 munmap(log_mapped, mapsz);
1738 if (cutoff_time)
1739 *cutoff_time = date;
1740 if (cutoff_tz)
1741 *cutoff_tz = tz;
1742 if (cutoff_cnt)
1743 *cutoff_cnt = reccnt;
1744 return 1;
1747 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1749 const char *logfile;
1750 FILE *logfp;
1751 struct strbuf sb = STRBUF_INIT;
1752 int ret = 0;
1754 logfile = git_path("logs/%s", ref);
1755 logfp = fopen(logfile, "r");
1756 if (!logfp)
1757 return -1;
1759 if (ofs) {
1760 struct stat statbuf;
1761 if (fstat(fileno(logfp), &statbuf) ||
1762 statbuf.st_size < ofs ||
1763 fseek(logfp, -ofs, SEEK_END) ||
1764 strbuf_getwholeline(&sb, logfp, '\n')) {
1765 fclose(logfp);
1766 strbuf_release(&sb);
1767 return -1;
1771 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1772 unsigned char osha1[20], nsha1[20];
1773 char *email_end, *message;
1774 unsigned long timestamp;
1775 int tz;
1777 /* old SP new SP name <email> SP time TAB msg LF */
1778 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1779 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1780 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1781 !(email_end = strchr(sb.buf + 82, '>')) ||
1782 email_end[1] != ' ' ||
1783 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1784 !message || message[0] != ' ' ||
1785 (message[1] != '+' && message[1] != '-') ||
1786 !isdigit(message[2]) || !isdigit(message[3]) ||
1787 !isdigit(message[4]) || !isdigit(message[5]))
1788 continue; /* corrupt? */
1789 email_end[1] = '\0';
1790 tz = strtol(message + 1, NULL, 10);
1791 if (message[6] != '\t')
1792 message += 6;
1793 else
1794 message += 7;
1795 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1796 cb_data);
1797 if (ret)
1798 break;
1800 fclose(logfp);
1801 strbuf_release(&sb);
1802 return ret;
1805 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1807 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1810 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1812 DIR *dir = opendir(git_path("logs/%s", base));
1813 int retval = 0;
1815 if (dir) {
1816 struct dirent *de;
1817 int baselen = strlen(base);
1818 char *log = xmalloc(baselen + 257);
1820 memcpy(log, base, baselen);
1821 if (baselen && base[baselen-1] != '/')
1822 log[baselen++] = '/';
1824 while ((de = readdir(dir)) != NULL) {
1825 struct stat st;
1826 int namelen;
1828 if (de->d_name[0] == '.')
1829 continue;
1830 namelen = strlen(de->d_name);
1831 if (namelen > 255)
1832 continue;
1833 if (has_extension(de->d_name, ".lock"))
1834 continue;
1835 memcpy(log + baselen, de->d_name, namelen+1);
1836 if (stat(git_path("logs/%s", log), &st) < 0)
1837 continue;
1838 if (S_ISDIR(st.st_mode)) {
1839 retval = do_for_each_reflog(log, fn, cb_data);
1840 } else {
1841 unsigned char sha1[20];
1842 if (!resolve_ref(log, sha1, 0, NULL))
1843 retval = error("bad ref for %s", log);
1844 else
1845 retval = fn(log, sha1, 0, cb_data);
1847 if (retval)
1848 break;
1850 free(log);
1851 closedir(dir);
1853 else if (*base)
1854 return errno;
1855 return retval;
1858 int for_each_reflog(each_ref_fn fn, void *cb_data)
1860 return do_for_each_reflog("", fn, cb_data);
1863 int update_ref(const char *action, const char *refname,
1864 const unsigned char *sha1, const unsigned char *oldval,
1865 int flags, enum action_on_err onerr)
1867 static struct ref_lock *lock;
1868 lock = lock_any_ref_for_update(refname, oldval, flags);
1869 if (!lock) {
1870 const char *str = "Cannot lock the ref '%s'.";
1871 switch (onerr) {
1872 case MSG_ON_ERR: error(str, refname); break;
1873 case DIE_ON_ERR: die(str, refname); break;
1874 case QUIET_ON_ERR: break;
1876 return 1;
1878 if (write_ref_sha1(lock, sha1, action) < 0) {
1879 const char *str = "Cannot update the ref '%s'.";
1880 switch (onerr) {
1881 case MSG_ON_ERR: error(str, refname); break;
1882 case DIE_ON_ERR: die(str, refname); break;
1883 case QUIET_ON_ERR: break;
1885 return 1;
1887 return 0;
1890 int ref_exists(const char *refname)
1892 unsigned char sha1[20];
1893 return !!resolve_ref(refname, sha1, 1, NULL);
1896 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1898 for ( ; list; list = list->next)
1899 if (!strcmp(list->name, name))
1900 return (struct ref *)list;
1901 return NULL;
1905 * generate a format suitable for scanf from a ref_rev_parse_rules
1906 * rule, that is replace the "%.*s" spec with a "%s" spec
1908 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1910 char *spec;
1912 spec = strstr(rule, "%.*s");
1913 if (!spec || strstr(spec + 4, "%.*s"))
1914 die("invalid rule in ref_rev_parse_rules: %s", rule);
1916 /* copy all until spec */
1917 strncpy(scanf_fmt, rule, spec - rule);
1918 scanf_fmt[spec - rule] = '\0';
1919 /* copy new spec */
1920 strcat(scanf_fmt, "%s");
1921 /* copy remaining rule */
1922 strcat(scanf_fmt, spec + 4);
1924 return;
1927 char *shorten_unambiguous_ref(const char *ref, int strict)
1929 int i;
1930 static char **scanf_fmts;
1931 static int nr_rules;
1932 char *short_name;
1934 /* pre generate scanf formats from ref_rev_parse_rules[] */
1935 if (!nr_rules) {
1936 size_t total_len = 0;
1938 /* the rule list is NULL terminated, count them first */
1939 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1940 /* no +1 because strlen("%s") < strlen("%.*s") */
1941 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1943 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1945 total_len = 0;
1946 for (i = 0; i < nr_rules; i++) {
1947 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1948 + total_len;
1949 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1950 total_len += strlen(ref_rev_parse_rules[i]);
1954 /* bail out if there are no rules */
1955 if (!nr_rules)
1956 return xstrdup(ref);
1958 /* buffer for scanf result, at most ref must fit */
1959 short_name = xstrdup(ref);
1961 /* skip first rule, it will always match */
1962 for (i = nr_rules - 1; i > 0 ; --i) {
1963 int j;
1964 int rules_to_fail = i;
1965 int short_name_len;
1967 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1968 continue;
1970 short_name_len = strlen(short_name);
1973 * in strict mode, all (except the matched one) rules
1974 * must fail to resolve to a valid non-ambiguous ref
1976 if (strict)
1977 rules_to_fail = nr_rules;
1980 * check if the short name resolves to a valid ref,
1981 * but use only rules prior to the matched one
1983 for (j = 0; j < rules_to_fail; j++) {
1984 const char *rule = ref_rev_parse_rules[j];
1985 unsigned char short_objectname[20];
1986 char refname[PATH_MAX];
1988 /* skip matched rule */
1989 if (i == j)
1990 continue;
1993 * the short name is ambiguous, if it resolves
1994 * (with this previous rule) to a valid ref
1995 * read_ref() returns 0 on success
1997 mksnpath(refname, sizeof(refname),
1998 rule, short_name_len, short_name);
1999 if (!read_ref(refname, short_objectname))
2000 break;
2004 * short name is non-ambiguous if all previous rules
2005 * haven't resolved to a valid ref
2007 if (j == rules_to_fail)
2008 return short_name;
2011 free(short_name);
2012 return xstrdup(ref);