Merge branch 'cb/maint-orphan-merge-noclobber'
[git/kirr.git] / refs.c
blobe3c05110e58ca5684f9c43b1e1a5eb2587c96828
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_list {
12 struct ref_list *next;
13 unsigned char flag; /* ISSYMREF? ISPACKED? */
14 unsigned char sha1[20];
15 unsigned char peeled[20];
16 char name[FLEX_ARRAY];
19 static const char *parse_ref_line(char *line, unsigned char *sha1)
22 * 42: the answer to everything.
24 * In this case, it happens to be the answer to
25 * 40 (length of sha1 hex representation)
26 * +1 (space in between hex and name)
27 * +1 (newline at the end of the line)
29 int len = strlen(line) - 42;
31 if (len <= 0)
32 return NULL;
33 if (get_sha1_hex(line, sha1) < 0)
34 return NULL;
35 if (!isspace(line[40]))
36 return NULL;
37 line += 41;
38 if (isspace(*line))
39 return NULL;
40 if (line[len] != '\n')
41 return NULL;
42 line[len] = 0;
44 return line;
47 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
48 int flag, struct ref_list *list,
49 struct ref_list **new_entry)
51 int len;
52 struct ref_list *entry;
54 /* Allocate it and add it in.. */
55 len = strlen(name) + 1;
56 entry = xmalloc(sizeof(struct ref_list) + len);
57 hashcpy(entry->sha1, sha1);
58 hashclr(entry->peeled);
59 memcpy(entry->name, name, len);
60 entry->flag = flag;
61 entry->next = list;
62 if (new_entry)
63 *new_entry = entry;
64 return entry;
67 /* merge sort the ref list */
68 static struct ref_list *sort_ref_list(struct ref_list *list)
70 int psize, qsize, last_merge_count, cmp;
71 struct ref_list *p, *q, *l, *e;
72 struct ref_list *new_list = list;
73 int k = 1;
74 int merge_count = 0;
76 if (!list)
77 return list;
79 do {
80 last_merge_count = merge_count;
81 merge_count = 0;
83 psize = 0;
85 p = new_list;
86 q = new_list;
87 new_list = NULL;
88 l = NULL;
90 while (p) {
91 merge_count++;
93 while (psize < k && q->next) {
94 q = q->next;
95 psize++;
97 qsize = k;
99 while ((psize > 0) || (qsize > 0 && q)) {
100 if (qsize == 0 || !q) {
101 e = p;
102 p = p->next;
103 psize--;
104 } else if (psize == 0) {
105 e = q;
106 q = q->next;
107 qsize--;
108 } else {
109 cmp = strcmp(q->name, p->name);
110 if (cmp < 0) {
111 e = q;
112 q = q->next;
113 qsize--;
114 } else if (cmp > 0) {
115 e = p;
116 p = p->next;
117 psize--;
118 } else {
119 if (hashcmp(q->sha1, p->sha1))
120 die("Duplicated ref, and SHA1s don't match: %s",
121 q->name);
122 warning("Duplicated ref: %s", q->name);
123 e = q;
124 q = q->next;
125 qsize--;
126 free(e);
127 e = p;
128 p = p->next;
129 psize--;
133 e->next = NULL;
135 if (l)
136 l->next = e;
137 if (!new_list)
138 new_list = e;
139 l = e;
142 p = q;
145 k = k * 2;
146 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
148 return new_list;
152 * Future: need to be in "struct repository"
153 * when doing a full libification.
155 static struct cached_refs {
156 char did_loose;
157 char did_packed;
158 struct ref_list *loose;
159 struct ref_list *packed;
160 } cached_refs, submodule_refs;
161 static struct ref_list *current_ref;
163 static struct ref_list *extra_refs;
165 static void free_ref_list(struct ref_list *list)
167 struct ref_list *next;
168 for ( ; list; list = next) {
169 next = list->next;
170 free(list);
174 static void invalidate_cached_refs(void)
176 struct cached_refs *ca = &cached_refs;
178 if (ca->did_loose && ca->loose)
179 free_ref_list(ca->loose);
180 if (ca->did_packed && ca->packed)
181 free_ref_list(ca->packed);
182 ca->loose = ca->packed = NULL;
183 ca->did_loose = ca->did_packed = 0;
186 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
188 struct ref_list *list = NULL;
189 struct ref_list *last = NULL;
190 char refline[PATH_MAX];
191 int flag = REF_ISPACKED;
193 while (fgets(refline, sizeof(refline), f)) {
194 unsigned char sha1[20];
195 const char *name;
196 static const char header[] = "# pack-refs with:";
198 if (!strncmp(refline, header, sizeof(header)-1)) {
199 const char *traits = refline + sizeof(header) - 1;
200 if (strstr(traits, " peeled "))
201 flag |= REF_KNOWS_PEELED;
202 /* perhaps other traits later as well */
203 continue;
206 name = parse_ref_line(refline, sha1);
207 if (name) {
208 list = add_ref(name, sha1, flag, list, &last);
209 continue;
211 if (last &&
212 refline[0] == '^' &&
213 strlen(refline) == 42 &&
214 refline[41] == '\n' &&
215 !get_sha1_hex(refline + 1, sha1))
216 hashcpy(last->peeled, sha1);
218 cached_refs->packed = sort_ref_list(list);
221 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
223 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
226 void clear_extra_refs(void)
228 free_ref_list(extra_refs);
229 extra_refs = NULL;
232 static struct ref_list *get_packed_refs(const char *submodule)
234 const char *packed_refs_file;
235 struct cached_refs *refs;
237 if (submodule) {
238 packed_refs_file = git_path_submodule(submodule, "packed-refs");
239 refs = &submodule_refs;
240 free_ref_list(refs->packed);
241 } else {
242 packed_refs_file = git_path("packed-refs");
243 refs = &cached_refs;
246 if (!refs->did_packed || submodule) {
247 FILE *f = fopen(packed_refs_file, "r");
248 refs->packed = NULL;
249 if (f) {
250 read_packed_refs(f, refs);
251 fclose(f);
253 refs->did_packed = 1;
255 return refs->packed;
258 static struct ref_list *get_ref_dir(const char *submodule, const char *base,
259 struct ref_list *list)
261 DIR *dir;
262 const char *path;
264 if (submodule)
265 path = git_path_submodule(submodule, "%s", base);
266 else
267 path = git_path("%s", base);
270 dir = opendir(path);
272 if (dir) {
273 struct dirent *de;
274 int baselen = strlen(base);
275 char *ref = xmalloc(baselen + 257);
277 memcpy(ref, base, baselen);
278 if (baselen && base[baselen-1] != '/')
279 ref[baselen++] = '/';
281 while ((de = readdir(dir)) != NULL) {
282 unsigned char sha1[20];
283 struct stat st;
284 int flag;
285 int namelen;
286 const char *refdir;
288 if (de->d_name[0] == '.')
289 continue;
290 namelen = strlen(de->d_name);
291 if (namelen > 255)
292 continue;
293 if (has_extension(de->d_name, ".lock"))
294 continue;
295 memcpy(ref + baselen, de->d_name, namelen+1);
296 refdir = submodule
297 ? git_path_submodule(submodule, "%s", ref)
298 : git_path("%s", ref);
299 if (stat(refdir, &st) < 0)
300 continue;
301 if (S_ISDIR(st.st_mode)) {
302 list = get_ref_dir(submodule, ref, list);
303 continue;
305 if (submodule) {
306 hashclr(sha1);
307 flag = 0;
308 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
309 hashclr(sha1);
310 flag |= REF_BROKEN;
312 } else
313 if (!resolve_ref(ref, sha1, 1, &flag)) {
314 hashclr(sha1);
315 flag |= REF_BROKEN;
317 list = add_ref(ref, sha1, flag, list, NULL);
319 free(ref);
320 closedir(dir);
322 return sort_ref_list(list);
325 struct warn_if_dangling_data {
326 FILE *fp;
327 const char *refname;
328 const char *msg_fmt;
331 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
332 int flags, void *cb_data)
334 struct warn_if_dangling_data *d = cb_data;
335 const char *resolves_to;
336 unsigned char junk[20];
338 if (!(flags & REF_ISSYMREF))
339 return 0;
341 resolves_to = resolve_ref(refname, junk, 0, NULL);
342 if (!resolves_to || strcmp(resolves_to, d->refname))
343 return 0;
345 fprintf(d->fp, d->msg_fmt, refname);
346 return 0;
349 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
351 struct warn_if_dangling_data data;
353 data.fp = fp;
354 data.refname = refname;
355 data.msg_fmt = msg_fmt;
356 for_each_rawref(warn_if_dangling_symref, &data);
359 static struct ref_list *get_loose_refs(const char *submodule)
361 if (submodule) {
362 free_ref_list(submodule_refs.loose);
363 submodule_refs.loose = get_ref_dir(submodule, "refs", NULL);
364 return submodule_refs.loose;
367 if (!cached_refs.did_loose) {
368 cached_refs.loose = get_ref_dir(NULL, "refs", NULL);
369 cached_refs.did_loose = 1;
371 return cached_refs.loose;
374 /* We allow "recursive" symbolic refs. Only within reason, though */
375 #define MAXDEPTH 5
376 #define MAXREFLEN (1024)
378 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
380 FILE *f;
381 struct cached_refs refs;
382 struct ref_list *ref;
383 int retval;
385 strcpy(name + pathlen, "packed-refs");
386 f = fopen(name, "r");
387 if (!f)
388 return -1;
389 read_packed_refs(f, &refs);
390 fclose(f);
391 ref = refs.packed;
392 retval = -1;
393 while (ref) {
394 if (!strcmp(ref->name, refname)) {
395 retval = 0;
396 memcpy(result, ref->sha1, 20);
397 break;
399 ref = ref->next;
401 free_ref_list(refs.packed);
402 return retval;
405 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
407 int fd, len = strlen(refname);
408 char buffer[128], *p;
410 if (recursion > MAXDEPTH || len > MAXREFLEN)
411 return -1;
412 memcpy(name + pathlen, refname, len+1);
413 fd = open(name, O_RDONLY);
414 if (fd < 0)
415 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
417 len = read(fd, buffer, sizeof(buffer)-1);
418 close(fd);
419 if (len < 0)
420 return -1;
421 while (len && isspace(buffer[len-1]))
422 len--;
423 buffer[len] = 0;
425 /* Was it a detached head or an old-fashioned symlink? */
426 if (!get_sha1_hex(buffer, result))
427 return 0;
429 /* Symref? */
430 if (strncmp(buffer, "ref:", 4))
431 return -1;
432 p = buffer + 4;
433 while (isspace(*p))
434 p++;
436 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
439 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
441 int len = strlen(path), retval;
442 char *gitdir;
443 const char *tmp;
445 while (len && path[len-1] == '/')
446 len--;
447 if (!len)
448 return -1;
449 gitdir = xmalloc(len + MAXREFLEN + 8);
450 memcpy(gitdir, path, len);
451 memcpy(gitdir + len, "/.git", 6);
452 len += 5;
454 tmp = read_gitfile_gently(gitdir);
455 if (tmp) {
456 free(gitdir);
457 len = strlen(tmp);
458 gitdir = xmalloc(len + MAXREFLEN + 3);
459 memcpy(gitdir, tmp, len);
461 gitdir[len] = '/';
462 gitdir[++len] = '\0';
463 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
464 free(gitdir);
465 return retval;
469 * If the "reading" argument is set, this function finds out what _object_
470 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
471 * has to exist, and if it is symbolic, it has to point at an existing ref,
472 * because the "read" goes through the symref to the ref it points at.
474 * The access that is not "reading" may often be "writing", but does not
475 * have to; it can be merely checking _where it leads to_. If it is a
476 * prelude to "writing" to the ref, a write to a symref that points at
477 * yet-to-be-born ref will create the real ref pointed by the symref.
478 * reading=0 allows the caller to check where such a symref leads to.
480 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
482 int depth = MAXDEPTH;
483 ssize_t len;
484 char buffer[256];
485 static char ref_buffer[256];
487 if (flag)
488 *flag = 0;
490 for (;;) {
491 char path[PATH_MAX];
492 struct stat st;
493 char *buf;
494 int fd;
496 if (--depth < 0)
497 return NULL;
499 git_snpath(path, sizeof(path), "%s", ref);
500 /* Special case: non-existing file. */
501 if (lstat(path, &st) < 0) {
502 struct ref_list *list = get_packed_refs(NULL);
503 while (list) {
504 if (!strcmp(ref, list->name)) {
505 hashcpy(sha1, list->sha1);
506 if (flag)
507 *flag |= REF_ISPACKED;
508 return ref;
510 list = list->next;
512 if (reading || errno != ENOENT)
513 return NULL;
514 hashclr(sha1);
515 return ref;
518 /* Follow "normalized" - ie "refs/.." symlinks by hand */
519 if (S_ISLNK(st.st_mode)) {
520 len = readlink(path, buffer, sizeof(buffer)-1);
521 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
522 buffer[len] = 0;
523 strcpy(ref_buffer, buffer);
524 ref = ref_buffer;
525 if (flag)
526 *flag |= REF_ISSYMREF;
527 continue;
531 /* Is it a directory? */
532 if (S_ISDIR(st.st_mode)) {
533 errno = EISDIR;
534 return NULL;
538 * Anything else, just open it and try to use it as
539 * a ref
541 fd = open(path, O_RDONLY);
542 if (fd < 0)
543 return NULL;
544 len = read_in_full(fd, buffer, sizeof(buffer)-1);
545 close(fd);
548 * Is it a symbolic ref?
550 if (len < 4 || memcmp("ref:", buffer, 4))
551 break;
552 buf = buffer + 4;
553 len -= 4;
554 while (len && isspace(*buf))
555 buf++, len--;
556 while (len && isspace(buf[len-1]))
557 len--;
558 buf[len] = 0;
559 memcpy(ref_buffer, buf, len + 1);
560 ref = ref_buffer;
561 if (flag)
562 *flag |= REF_ISSYMREF;
564 if (len < 40 || get_sha1_hex(buffer, sha1))
565 return NULL;
566 return ref;
569 /* The argument to filter_refs */
570 struct ref_filter {
571 const char *pattern;
572 each_ref_fn *fn;
573 void *cb_data;
576 int read_ref(const char *ref, unsigned char *sha1)
578 if (resolve_ref(ref, sha1, 1, NULL))
579 return 0;
580 return -1;
583 #define DO_FOR_EACH_INCLUDE_BROKEN 01
584 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
585 int flags, void *cb_data, struct ref_list *entry)
587 if (strncmp(base, entry->name, trim))
588 return 0;
590 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
591 if (entry->flag & REF_BROKEN)
592 return 0; /* ignore dangling symref */
593 if (!has_sha1_file(entry->sha1)) {
594 error("%s does not point to a valid object!", entry->name);
595 return 0;
598 current_ref = entry;
599 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
602 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
603 void *data)
605 struct ref_filter *filter = (struct ref_filter *)data;
606 if (fnmatch(filter->pattern, ref, 0))
607 return 0;
608 return filter->fn(ref, sha, flags, filter->cb_data);
611 int peel_ref(const char *ref, unsigned char *sha1)
613 int flag;
614 unsigned char base[20];
615 struct object *o;
617 if (current_ref && (current_ref->name == ref
618 || !strcmp(current_ref->name, ref))) {
619 if (current_ref->flag & REF_KNOWS_PEELED) {
620 hashcpy(sha1, current_ref->peeled);
621 return 0;
623 hashcpy(base, current_ref->sha1);
624 goto fallback;
627 if (!resolve_ref(ref, base, 1, &flag))
628 return -1;
630 if ((flag & REF_ISPACKED)) {
631 struct ref_list *list = get_packed_refs(NULL);
633 while (list) {
634 if (!strcmp(list->name, ref)) {
635 if (list->flag & REF_KNOWS_PEELED) {
636 hashcpy(sha1, list->peeled);
637 return 0;
639 /* older pack-refs did not leave peeled ones */
640 break;
642 list = list->next;
646 fallback:
647 o = parse_object(base);
648 if (o && o->type == OBJ_TAG) {
649 o = deref_tag(o, ref, 0);
650 if (o) {
651 hashcpy(sha1, o->sha1);
652 return 0;
655 return -1;
658 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
659 int trim, int flags, void *cb_data)
661 int retval = 0;
662 struct ref_list *packed = get_packed_refs(submodule);
663 struct ref_list *loose = get_loose_refs(submodule);
665 struct ref_list *extra;
667 for (extra = extra_refs; extra; extra = extra->next)
668 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
670 while (packed && loose) {
671 struct ref_list *entry;
672 int cmp = strcmp(packed->name, loose->name);
673 if (!cmp) {
674 packed = packed->next;
675 continue;
677 if (cmp > 0) {
678 entry = loose;
679 loose = loose->next;
680 } else {
681 entry = packed;
682 packed = packed->next;
684 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
685 if (retval)
686 goto end_each;
689 for (packed = packed ? packed : loose; packed; packed = packed->next) {
690 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
691 if (retval)
692 goto end_each;
695 end_each:
696 current_ref = NULL;
697 return retval;
701 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
703 unsigned char sha1[20];
704 int flag;
706 if (submodule) {
707 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
708 return fn("HEAD", sha1, 0, cb_data);
710 return 0;
713 if (resolve_ref("HEAD", sha1, 1, &flag))
714 return fn("HEAD", sha1, flag, cb_data);
716 return 0;
719 int head_ref(each_ref_fn fn, void *cb_data)
721 return do_head_ref(NULL, fn, cb_data);
724 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
726 return do_head_ref(submodule, fn, cb_data);
729 int for_each_ref(each_ref_fn fn, void *cb_data)
731 return do_for_each_ref(NULL, "refs/", fn, 0, 0, cb_data);
734 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
736 return do_for_each_ref(submodule, "refs/", fn, 0, 0, cb_data);
739 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
741 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
744 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
745 each_ref_fn fn, void *cb_data)
747 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
750 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
752 return for_each_ref_in("refs/tags/", fn, cb_data);
755 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
757 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
760 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
762 return for_each_ref_in("refs/heads/", fn, cb_data);
765 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
767 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
770 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
772 return for_each_ref_in("refs/remotes/", fn, cb_data);
775 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
777 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
780 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
782 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
785 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
786 const char *prefix, void *cb_data)
788 struct strbuf real_pattern = STRBUF_INIT;
789 struct ref_filter filter;
790 int ret;
792 if (!prefix && prefixcmp(pattern, "refs/"))
793 strbuf_addstr(&real_pattern, "refs/");
794 else if (prefix)
795 strbuf_addstr(&real_pattern, prefix);
796 strbuf_addstr(&real_pattern, pattern);
798 if (!has_glob_specials(pattern)) {
799 /* Append implied '/' '*' if not present. */
800 if (real_pattern.buf[real_pattern.len - 1] != '/')
801 strbuf_addch(&real_pattern, '/');
802 /* No need to check for '*', there is none. */
803 strbuf_addch(&real_pattern, '*');
806 filter.pattern = real_pattern.buf;
807 filter.fn = fn;
808 filter.cb_data = cb_data;
809 ret = for_each_ref(filter_refs, &filter);
811 strbuf_release(&real_pattern);
812 return ret;
815 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
817 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
820 int for_each_rawref(each_ref_fn fn, void *cb_data)
822 return do_for_each_ref(NULL, "refs/", fn, 0,
823 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
827 * Make sure "ref" is something reasonable to have under ".git/refs/";
828 * We do not like it if:
830 * - any path component of it begins with ".", or
831 * - it has double dots "..", or
832 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
833 * - it ends with a "/".
834 * - it ends with ".lock"
835 * - it contains a "\" (backslash)
838 static inline int bad_ref_char(int ch)
840 if (((unsigned) ch) <= ' ' ||
841 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
842 return 1;
843 /* 2.13 Pattern Matching Notation */
844 if (ch == '?' || ch == '[') /* Unsupported */
845 return 1;
846 if (ch == '*') /* Supported at the end */
847 return 2;
848 return 0;
851 int check_ref_format(const char *ref)
853 int ch, level, bad_type, last;
854 int ret = CHECK_REF_FORMAT_OK;
855 const char *cp = ref;
857 level = 0;
858 while (1) {
859 while ((ch = *cp++) == '/')
860 ; /* tolerate duplicated slashes */
861 if (!ch)
862 /* should not end with slashes */
863 return CHECK_REF_FORMAT_ERROR;
865 /* we are at the beginning of the path component */
866 if (ch == '.')
867 return CHECK_REF_FORMAT_ERROR;
868 bad_type = bad_ref_char(ch);
869 if (bad_type) {
870 if (bad_type == 2 && (!*cp || *cp == '/') &&
871 ret == CHECK_REF_FORMAT_OK)
872 ret = CHECK_REF_FORMAT_WILDCARD;
873 else
874 return CHECK_REF_FORMAT_ERROR;
877 last = ch;
878 /* scan the rest of the path component */
879 while ((ch = *cp++) != 0) {
880 bad_type = bad_ref_char(ch);
881 if (bad_type)
882 return CHECK_REF_FORMAT_ERROR;
883 if (ch == '/')
884 break;
885 if (last == '.' && ch == '.')
886 return CHECK_REF_FORMAT_ERROR;
887 if (last == '@' && ch == '{')
888 return CHECK_REF_FORMAT_ERROR;
889 last = ch;
891 level++;
892 if (!ch) {
893 if (ref <= cp - 2 && cp[-2] == '.')
894 return CHECK_REF_FORMAT_ERROR;
895 if (level < 2)
896 return CHECK_REF_FORMAT_ONELEVEL;
897 if (has_extension(ref, ".lock"))
898 return CHECK_REF_FORMAT_ERROR;
899 return ret;
904 const char *prettify_refname(const char *name)
906 return name + (
907 !prefixcmp(name, "refs/heads/") ? 11 :
908 !prefixcmp(name, "refs/tags/") ? 10 :
909 !prefixcmp(name, "refs/remotes/") ? 13 :
913 const char *ref_rev_parse_rules[] = {
914 "%.*s",
915 "refs/%.*s",
916 "refs/tags/%.*s",
917 "refs/heads/%.*s",
918 "refs/remotes/%.*s",
919 "refs/remotes/%.*s/HEAD",
920 NULL
923 const char *ref_fetch_rules[] = {
924 "%.*s",
925 "refs/%.*s",
926 "refs/heads/%.*s",
927 NULL
930 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
932 const char **p;
933 const int abbrev_name_len = strlen(abbrev_name);
935 for (p = rules; *p; p++) {
936 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
937 return 1;
941 return 0;
944 static struct ref_lock *verify_lock(struct ref_lock *lock,
945 const unsigned char *old_sha1, int mustexist)
947 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
948 error("Can't verify ref %s", lock->ref_name);
949 unlock_ref(lock);
950 return NULL;
952 if (hashcmp(lock->old_sha1, old_sha1)) {
953 error("Ref %s is at %s but expected %s", lock->ref_name,
954 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
955 unlock_ref(lock);
956 return NULL;
958 return lock;
961 static int remove_empty_directories(const char *file)
963 /* we want to create a file but there is a directory there;
964 * if that is an empty directory (or a directory that contains
965 * only empty directories), remove them.
967 struct strbuf path;
968 int result;
970 strbuf_init(&path, 20);
971 strbuf_addstr(&path, file);
973 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
975 strbuf_release(&path);
977 return result;
980 static int is_refname_available(const char *ref, const char *oldref,
981 struct ref_list *list, int quiet)
983 int namlen = strlen(ref); /* e.g. 'foo/bar' */
984 while (list) {
985 /* list->name could be 'foo' or 'foo/bar/baz' */
986 if (!oldref || strcmp(oldref, list->name)) {
987 int len = strlen(list->name);
988 int cmplen = (namlen < len) ? namlen : len;
989 const char *lead = (namlen < len) ? list->name : ref;
990 if (!strncmp(ref, list->name, cmplen) &&
991 lead[cmplen] == '/') {
992 if (!quiet)
993 error("'%s' exists; cannot create '%s'",
994 list->name, ref);
995 return 0;
998 list = list->next;
1000 return 1;
1003 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1005 char *ref_file;
1006 const char *orig_ref = ref;
1007 struct ref_lock *lock;
1008 int last_errno = 0;
1009 int type, lflags;
1010 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1011 int missing = 0;
1013 lock = xcalloc(1, sizeof(struct ref_lock));
1014 lock->lock_fd = -1;
1016 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1017 if (!ref && errno == EISDIR) {
1018 /* we are trying to lock foo but we used to
1019 * have foo/bar which now does not exist;
1020 * it is normal for the empty directory 'foo'
1021 * to remain.
1023 ref_file = git_path("%s", orig_ref);
1024 if (remove_empty_directories(ref_file)) {
1025 last_errno = errno;
1026 error("there are still refs under '%s'", orig_ref);
1027 goto error_return;
1029 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1031 if (type_p)
1032 *type_p = type;
1033 if (!ref) {
1034 last_errno = errno;
1035 error("unable to resolve reference %s: %s",
1036 orig_ref, strerror(errno));
1037 goto error_return;
1039 missing = is_null_sha1(lock->old_sha1);
1040 /* When the ref did not exist and we are creating it,
1041 * make sure there is no existing ref that is packed
1042 * whose name begins with our refname, nor a ref whose
1043 * name is a proper prefix of our refname.
1045 if (missing &&
1046 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1047 last_errno = ENOTDIR;
1048 goto error_return;
1051 lock->lk = xcalloc(1, sizeof(struct lock_file));
1053 lflags = LOCK_DIE_ON_ERROR;
1054 if (flags & REF_NODEREF) {
1055 ref = orig_ref;
1056 lflags |= LOCK_NODEREF;
1058 lock->ref_name = xstrdup(ref);
1059 lock->orig_ref_name = xstrdup(orig_ref);
1060 ref_file = git_path("%s", ref);
1061 if (missing)
1062 lock->force_write = 1;
1063 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1064 lock->force_write = 1;
1066 if (safe_create_leading_directories(ref_file)) {
1067 last_errno = errno;
1068 error("unable to create directory for %s", ref_file);
1069 goto error_return;
1072 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1073 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1075 error_return:
1076 unlock_ref(lock);
1077 errno = last_errno;
1078 return NULL;
1081 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1083 char refpath[PATH_MAX];
1084 if (check_ref_format(ref))
1085 return NULL;
1086 strcpy(refpath, mkpath("refs/%s", ref));
1087 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1090 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1092 switch (check_ref_format(ref)) {
1093 default:
1094 return NULL;
1095 case 0:
1096 case CHECK_REF_FORMAT_ONELEVEL:
1097 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1101 static struct lock_file packlock;
1103 static int repack_without_ref(const char *refname)
1105 struct ref_list *list, *packed_ref_list;
1106 int fd;
1107 int found = 0;
1109 packed_ref_list = get_packed_refs(NULL);
1110 for (list = packed_ref_list; list; list = list->next) {
1111 if (!strcmp(refname, list->name)) {
1112 found = 1;
1113 break;
1116 if (!found)
1117 return 0;
1118 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1119 if (fd < 0) {
1120 unable_to_lock_error(git_path("packed-refs"), errno);
1121 return error("cannot delete '%s' from packed refs", refname);
1124 for (list = packed_ref_list; list; list = list->next) {
1125 char line[PATH_MAX + 100];
1126 int len;
1128 if (!strcmp(refname, list->name))
1129 continue;
1130 len = snprintf(line, sizeof(line), "%s %s\n",
1131 sha1_to_hex(list->sha1), list->name);
1132 /* this should not happen but just being defensive */
1133 if (len > sizeof(line))
1134 die("too long a refname '%s'", list->name);
1135 write_or_die(fd, line, len);
1137 return commit_lock_file(&packlock);
1140 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1142 struct ref_lock *lock;
1143 int err, i = 0, ret = 0, flag = 0;
1145 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1146 if (!lock)
1147 return 1;
1148 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1149 /* loose */
1150 const char *path;
1152 if (!(delopt & REF_NODEREF)) {
1153 i = strlen(lock->lk->filename) - 5; /* .lock */
1154 lock->lk->filename[i] = 0;
1155 path = lock->lk->filename;
1156 } else {
1157 path = git_path("%s", refname);
1159 err = unlink_or_warn(path);
1160 if (err && errno != ENOENT)
1161 ret = 1;
1163 if (!(delopt & REF_NODEREF))
1164 lock->lk->filename[i] = '.';
1166 /* removing the loose one could have resurrected an earlier
1167 * packed one. Also, if it was not loose we need to repack
1168 * without it.
1170 ret |= repack_without_ref(refname);
1172 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1173 invalidate_cached_refs();
1174 unlock_ref(lock);
1175 return ret;
1179 * People using contrib's git-new-workdir have .git/logs/refs ->
1180 * /some/other/path/.git/logs/refs, and that may live on another device.
1182 * IOW, to avoid cross device rename errors, the temporary renamed log must
1183 * live into logs/refs.
1185 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1187 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1189 static const char renamed_ref[] = "RENAMED-REF";
1190 unsigned char sha1[20], orig_sha1[20];
1191 int flag = 0, logmoved = 0;
1192 struct ref_lock *lock;
1193 struct stat loginfo;
1194 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1195 const char *symref = NULL;
1197 if (log && S_ISLNK(loginfo.st_mode))
1198 return error("reflog for %s is a symlink", oldref);
1200 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1201 if (flag & REF_ISSYMREF)
1202 return error("refname %s is a symbolic ref, renaming it is not supported",
1203 oldref);
1204 if (!symref)
1205 return error("refname %s not found", oldref);
1207 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1208 return 1;
1210 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1211 return 1;
1213 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1214 if (!lock)
1215 return error("unable to lock %s", renamed_ref);
1216 lock->force_write = 1;
1217 if (write_ref_sha1(lock, orig_sha1, logmsg))
1218 return error("unable to save current sha1 in %s", renamed_ref);
1220 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1221 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1222 oldref, strerror(errno));
1224 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1225 error("unable to delete old %s", oldref);
1226 goto rollback;
1229 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1230 if (errno==EISDIR) {
1231 if (remove_empty_directories(git_path("%s", newref))) {
1232 error("Directory not empty: %s", newref);
1233 goto rollback;
1235 } else {
1236 error("unable to delete existing %s", newref);
1237 goto rollback;
1241 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1242 error("unable to create directory for %s", newref);
1243 goto rollback;
1246 retry:
1247 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1248 if (errno==EISDIR || errno==ENOTDIR) {
1250 * rename(a, b) when b is an existing
1251 * directory ought to result in ISDIR, but
1252 * Solaris 5.8 gives ENOTDIR. Sheesh.
1254 if (remove_empty_directories(git_path("logs/%s", newref))) {
1255 error("Directory not empty: logs/%s", newref);
1256 goto rollback;
1258 goto retry;
1259 } else {
1260 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1261 newref, strerror(errno));
1262 goto rollback;
1265 logmoved = log;
1267 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1268 if (!lock) {
1269 error("unable to lock %s for update", newref);
1270 goto rollback;
1272 lock->force_write = 1;
1273 hashcpy(lock->old_sha1, orig_sha1);
1274 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1275 error("unable to write current sha1 into %s", newref);
1276 goto rollback;
1279 return 0;
1281 rollback:
1282 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1283 if (!lock) {
1284 error("unable to lock %s for rollback", oldref);
1285 goto rollbacklog;
1288 lock->force_write = 1;
1289 flag = log_all_ref_updates;
1290 log_all_ref_updates = 0;
1291 if (write_ref_sha1(lock, orig_sha1, NULL))
1292 error("unable to write current sha1 into %s", oldref);
1293 log_all_ref_updates = flag;
1295 rollbacklog:
1296 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1297 error("unable to restore logfile %s from %s: %s",
1298 oldref, newref, strerror(errno));
1299 if (!logmoved && log &&
1300 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1301 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1302 oldref, strerror(errno));
1304 return 1;
1307 int close_ref(struct ref_lock *lock)
1309 if (close_lock_file(lock->lk))
1310 return -1;
1311 lock->lock_fd = -1;
1312 return 0;
1315 int commit_ref(struct ref_lock *lock)
1317 if (commit_lock_file(lock->lk))
1318 return -1;
1319 lock->lock_fd = -1;
1320 return 0;
1323 void unlock_ref(struct ref_lock *lock)
1325 /* Do not free lock->lk -- atexit() still looks at them */
1326 if (lock->lk)
1327 rollback_lock_file(lock->lk);
1328 free(lock->ref_name);
1329 free(lock->orig_ref_name);
1330 free(lock);
1334 * copy the reflog message msg to buf, which has been allocated sufficiently
1335 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1336 * because reflog file is one line per entry.
1338 static int copy_msg(char *buf, const char *msg)
1340 char *cp = buf;
1341 char c;
1342 int wasspace = 1;
1344 *cp++ = '\t';
1345 while ((c = *msg++)) {
1346 if (wasspace && isspace(c))
1347 continue;
1348 wasspace = isspace(c);
1349 if (wasspace)
1350 c = ' ';
1351 *cp++ = c;
1353 while (buf < cp && isspace(cp[-1]))
1354 cp--;
1355 *cp++ = '\n';
1356 return cp - buf;
1359 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1361 int logfd, oflags = O_APPEND | O_WRONLY;
1363 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1364 if (log_all_ref_updates &&
1365 (!prefixcmp(ref_name, "refs/heads/") ||
1366 !prefixcmp(ref_name, "refs/remotes/") ||
1367 !prefixcmp(ref_name, "refs/notes/") ||
1368 !strcmp(ref_name, "HEAD"))) {
1369 if (safe_create_leading_directories(logfile) < 0)
1370 return error("unable to create directory for %s",
1371 logfile);
1372 oflags |= O_CREAT;
1375 logfd = open(logfile, oflags, 0666);
1376 if (logfd < 0) {
1377 if (!(oflags & O_CREAT) && errno == ENOENT)
1378 return 0;
1380 if ((oflags & O_CREAT) && errno == EISDIR) {
1381 if (remove_empty_directories(logfile)) {
1382 return error("There are still logs under '%s'",
1383 logfile);
1385 logfd = open(logfile, oflags, 0666);
1388 if (logfd < 0)
1389 return error("Unable to append to %s: %s",
1390 logfile, strerror(errno));
1393 adjust_shared_perm(logfile);
1394 close(logfd);
1395 return 0;
1398 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1399 const unsigned char *new_sha1, const char *msg)
1401 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1402 unsigned maxlen, len;
1403 int msglen;
1404 char log_file[PATH_MAX];
1405 char *logrec;
1406 const char *committer;
1408 if (log_all_ref_updates < 0)
1409 log_all_ref_updates = !is_bare_repository();
1411 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1412 if (result)
1413 return result;
1415 logfd = open(log_file, oflags);
1416 if (logfd < 0)
1417 return 0;
1418 msglen = msg ? strlen(msg) : 0;
1419 committer = git_committer_info(0);
1420 maxlen = strlen(committer) + msglen + 100;
1421 logrec = xmalloc(maxlen);
1422 len = sprintf(logrec, "%s %s %s\n",
1423 sha1_to_hex(old_sha1),
1424 sha1_to_hex(new_sha1),
1425 committer);
1426 if (msglen)
1427 len += copy_msg(logrec + len - 1, msg) - 1;
1428 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1429 free(logrec);
1430 if (close(logfd) != 0 || written != len)
1431 return error("Unable to append to %s", log_file);
1432 return 0;
1435 static int is_branch(const char *refname)
1437 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1440 int write_ref_sha1(struct ref_lock *lock,
1441 const unsigned char *sha1, const char *logmsg)
1443 static char term = '\n';
1444 struct object *o;
1446 if (!lock)
1447 return -1;
1448 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1449 unlock_ref(lock);
1450 return 0;
1452 o = parse_object(sha1);
1453 if (!o) {
1454 error("Trying to write ref %s with nonexistant object %s",
1455 lock->ref_name, sha1_to_hex(sha1));
1456 unlock_ref(lock);
1457 return -1;
1459 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1460 error("Trying to write non-commit object %s to branch %s",
1461 sha1_to_hex(sha1), lock->ref_name);
1462 unlock_ref(lock);
1463 return -1;
1465 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1466 write_in_full(lock->lock_fd, &term, 1) != 1
1467 || close_ref(lock) < 0) {
1468 error("Couldn't write %s", lock->lk->filename);
1469 unlock_ref(lock);
1470 return -1;
1472 invalidate_cached_refs();
1473 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1474 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1475 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1476 unlock_ref(lock);
1477 return -1;
1479 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1481 * Special hack: If a branch is updated directly and HEAD
1482 * points to it (may happen on the remote side of a push
1483 * for example) then logically the HEAD reflog should be
1484 * updated too.
1485 * A generic solution implies reverse symref information,
1486 * but finding all symrefs pointing to the given branch
1487 * would be rather costly for this rare event (the direct
1488 * update of a branch) to be worth it. So let's cheat and
1489 * check with HEAD only which should cover 99% of all usage
1490 * scenarios (even 100% of the default ones).
1492 unsigned char head_sha1[20];
1493 int head_flag;
1494 const char *head_ref;
1495 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1496 if (head_ref && (head_flag & REF_ISSYMREF) &&
1497 !strcmp(head_ref, lock->ref_name))
1498 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1500 if (commit_ref(lock)) {
1501 error("Couldn't set %s", lock->ref_name);
1502 unlock_ref(lock);
1503 return -1;
1505 unlock_ref(lock);
1506 return 0;
1509 int create_symref(const char *ref_target, const char *refs_heads_master,
1510 const char *logmsg)
1512 const char *lockpath;
1513 char ref[1000];
1514 int fd, len, written;
1515 char *git_HEAD = git_pathdup("%s", ref_target);
1516 unsigned char old_sha1[20], new_sha1[20];
1518 if (logmsg && read_ref(ref_target, old_sha1))
1519 hashclr(old_sha1);
1521 if (safe_create_leading_directories(git_HEAD) < 0)
1522 return error("unable to create directory for %s", git_HEAD);
1524 #ifndef NO_SYMLINK_HEAD
1525 if (prefer_symlink_refs) {
1526 unlink(git_HEAD);
1527 if (!symlink(refs_heads_master, git_HEAD))
1528 goto done;
1529 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1531 #endif
1533 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1534 if (sizeof(ref) <= len) {
1535 error("refname too long: %s", refs_heads_master);
1536 goto error_free_return;
1538 lockpath = mkpath("%s.lock", git_HEAD);
1539 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1540 if (fd < 0) {
1541 error("Unable to open %s for writing", lockpath);
1542 goto error_free_return;
1544 written = write_in_full(fd, ref, len);
1545 if (close(fd) != 0 || written != len) {
1546 error("Unable to write to %s", lockpath);
1547 goto error_unlink_return;
1549 if (rename(lockpath, git_HEAD) < 0) {
1550 error("Unable to create %s", git_HEAD);
1551 goto error_unlink_return;
1553 if (adjust_shared_perm(git_HEAD)) {
1554 error("Unable to fix permissions on %s", lockpath);
1555 error_unlink_return:
1556 unlink_or_warn(lockpath);
1557 error_free_return:
1558 free(git_HEAD);
1559 return -1;
1562 #ifndef NO_SYMLINK_HEAD
1563 done:
1564 #endif
1565 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1566 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1568 free(git_HEAD);
1569 return 0;
1572 static char *ref_msg(const char *line, const char *endp)
1574 const char *ep;
1575 line += 82;
1576 ep = memchr(line, '\n', endp - line);
1577 if (!ep)
1578 ep = endp;
1579 return xmemdupz(line, ep - line);
1582 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)
1584 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1585 char *tz_c;
1586 int logfd, tz, reccnt = 0;
1587 struct stat st;
1588 unsigned long date;
1589 unsigned char logged_sha1[20];
1590 void *log_mapped;
1591 size_t mapsz;
1593 logfile = git_path("logs/%s", ref);
1594 logfd = open(logfile, O_RDONLY, 0);
1595 if (logfd < 0)
1596 die_errno("Unable to read log '%s'", logfile);
1597 fstat(logfd, &st);
1598 if (!st.st_size)
1599 die("Log %s is empty.", logfile);
1600 mapsz = xsize_t(st.st_size);
1601 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1602 logdata = log_mapped;
1603 close(logfd);
1605 lastrec = NULL;
1606 rec = logend = logdata + st.st_size;
1607 while (logdata < rec) {
1608 reccnt++;
1609 if (logdata < rec && *(rec-1) == '\n')
1610 rec--;
1611 lastgt = NULL;
1612 while (logdata < rec && *(rec-1) != '\n') {
1613 rec--;
1614 if (*rec == '>')
1615 lastgt = rec;
1617 if (!lastgt)
1618 die("Log %s is corrupt.", logfile);
1619 date = strtoul(lastgt + 1, &tz_c, 10);
1620 if (date <= at_time || cnt == 0) {
1621 tz = strtoul(tz_c, NULL, 10);
1622 if (msg)
1623 *msg = ref_msg(rec, logend);
1624 if (cutoff_time)
1625 *cutoff_time = date;
1626 if (cutoff_tz)
1627 *cutoff_tz = tz;
1628 if (cutoff_cnt)
1629 *cutoff_cnt = reccnt - 1;
1630 if (lastrec) {
1631 if (get_sha1_hex(lastrec, logged_sha1))
1632 die("Log %s is corrupt.", logfile);
1633 if (get_sha1_hex(rec + 41, sha1))
1634 die("Log %s is corrupt.", logfile);
1635 if (hashcmp(logged_sha1, sha1)) {
1636 warning("Log %s has gap after %s.",
1637 logfile, show_date(date, tz, DATE_RFC2822));
1640 else if (date == at_time) {
1641 if (get_sha1_hex(rec + 41, sha1))
1642 die("Log %s is corrupt.", logfile);
1644 else {
1645 if (get_sha1_hex(rec + 41, logged_sha1))
1646 die("Log %s is corrupt.", logfile);
1647 if (hashcmp(logged_sha1, sha1)) {
1648 warning("Log %s unexpectedly ended on %s.",
1649 logfile, show_date(date, tz, DATE_RFC2822));
1652 munmap(log_mapped, mapsz);
1653 return 0;
1655 lastrec = rec;
1656 if (cnt > 0)
1657 cnt--;
1660 rec = logdata;
1661 while (rec < logend && *rec != '>' && *rec != '\n')
1662 rec++;
1663 if (rec == logend || *rec == '\n')
1664 die("Log %s is corrupt.", logfile);
1665 date = strtoul(rec + 1, &tz_c, 10);
1666 tz = strtoul(tz_c, NULL, 10);
1667 if (get_sha1_hex(logdata, sha1))
1668 die("Log %s is corrupt.", logfile);
1669 if (is_null_sha1(sha1)) {
1670 if (get_sha1_hex(logdata + 41, sha1))
1671 die("Log %s is corrupt.", logfile);
1673 if (msg)
1674 *msg = ref_msg(logdata, logend);
1675 munmap(log_mapped, mapsz);
1677 if (cutoff_time)
1678 *cutoff_time = date;
1679 if (cutoff_tz)
1680 *cutoff_tz = tz;
1681 if (cutoff_cnt)
1682 *cutoff_cnt = reccnt;
1683 return 1;
1686 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1688 const char *logfile;
1689 FILE *logfp;
1690 struct strbuf sb = STRBUF_INIT;
1691 int ret = 0;
1693 logfile = git_path("logs/%s", ref);
1694 logfp = fopen(logfile, "r");
1695 if (!logfp)
1696 return -1;
1698 if (ofs) {
1699 struct stat statbuf;
1700 if (fstat(fileno(logfp), &statbuf) ||
1701 statbuf.st_size < ofs ||
1702 fseek(logfp, -ofs, SEEK_END) ||
1703 strbuf_getwholeline(&sb, logfp, '\n')) {
1704 fclose(logfp);
1705 strbuf_release(&sb);
1706 return -1;
1710 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1711 unsigned char osha1[20], nsha1[20];
1712 char *email_end, *message;
1713 unsigned long timestamp;
1714 int tz;
1716 /* old SP new SP name <email> SP time TAB msg LF */
1717 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1718 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1719 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1720 !(email_end = strchr(sb.buf + 82, '>')) ||
1721 email_end[1] != ' ' ||
1722 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1723 !message || message[0] != ' ' ||
1724 (message[1] != '+' && message[1] != '-') ||
1725 !isdigit(message[2]) || !isdigit(message[3]) ||
1726 !isdigit(message[4]) || !isdigit(message[5]))
1727 continue; /* corrupt? */
1728 email_end[1] = '\0';
1729 tz = strtol(message + 1, NULL, 10);
1730 if (message[6] != '\t')
1731 message += 6;
1732 else
1733 message += 7;
1734 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1735 cb_data);
1736 if (ret)
1737 break;
1739 fclose(logfp);
1740 strbuf_release(&sb);
1741 return ret;
1744 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1746 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1749 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1751 DIR *dir = opendir(git_path("logs/%s", base));
1752 int retval = 0;
1754 if (dir) {
1755 struct dirent *de;
1756 int baselen = strlen(base);
1757 char *log = xmalloc(baselen + 257);
1759 memcpy(log, base, baselen);
1760 if (baselen && base[baselen-1] != '/')
1761 log[baselen++] = '/';
1763 while ((de = readdir(dir)) != NULL) {
1764 struct stat st;
1765 int namelen;
1767 if (de->d_name[0] == '.')
1768 continue;
1769 namelen = strlen(de->d_name);
1770 if (namelen > 255)
1771 continue;
1772 if (has_extension(de->d_name, ".lock"))
1773 continue;
1774 memcpy(log + baselen, de->d_name, namelen+1);
1775 if (stat(git_path("logs/%s", log), &st) < 0)
1776 continue;
1777 if (S_ISDIR(st.st_mode)) {
1778 retval = do_for_each_reflog(log, fn, cb_data);
1779 } else {
1780 unsigned char sha1[20];
1781 if (!resolve_ref(log, sha1, 0, NULL))
1782 retval = error("bad ref for %s", log);
1783 else
1784 retval = fn(log, sha1, 0, cb_data);
1786 if (retval)
1787 break;
1789 free(log);
1790 closedir(dir);
1792 else if (*base)
1793 return errno;
1794 return retval;
1797 int for_each_reflog(each_ref_fn fn, void *cb_data)
1799 return do_for_each_reflog("", fn, cb_data);
1802 int update_ref(const char *action, const char *refname,
1803 const unsigned char *sha1, const unsigned char *oldval,
1804 int flags, enum action_on_err onerr)
1806 static struct ref_lock *lock;
1807 lock = lock_any_ref_for_update(refname, oldval, flags);
1808 if (!lock) {
1809 const char *str = "Cannot lock the ref '%s'.";
1810 switch (onerr) {
1811 case MSG_ON_ERR: error(str, refname); break;
1812 case DIE_ON_ERR: die(str, refname); break;
1813 case QUIET_ON_ERR: break;
1815 return 1;
1817 if (write_ref_sha1(lock, sha1, action) < 0) {
1818 const char *str = "Cannot update the ref '%s'.";
1819 switch (onerr) {
1820 case MSG_ON_ERR: error(str, refname); break;
1821 case DIE_ON_ERR: die(str, refname); break;
1822 case QUIET_ON_ERR: break;
1824 return 1;
1826 return 0;
1829 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1831 for ( ; list; list = list->next)
1832 if (!strcmp(list->name, name))
1833 return (struct ref *)list;
1834 return NULL;
1838 * generate a format suitable for scanf from a ref_rev_parse_rules
1839 * rule, that is replace the "%.*s" spec with a "%s" spec
1841 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1843 char *spec;
1845 spec = strstr(rule, "%.*s");
1846 if (!spec || strstr(spec + 4, "%.*s"))
1847 die("invalid rule in ref_rev_parse_rules: %s", rule);
1849 /* copy all until spec */
1850 strncpy(scanf_fmt, rule, spec - rule);
1851 scanf_fmt[spec - rule] = '\0';
1852 /* copy new spec */
1853 strcat(scanf_fmt, "%s");
1854 /* copy remaining rule */
1855 strcat(scanf_fmt, spec + 4);
1857 return;
1860 char *shorten_unambiguous_ref(const char *ref, int strict)
1862 int i;
1863 static char **scanf_fmts;
1864 static int nr_rules;
1865 char *short_name;
1867 /* pre generate scanf formats from ref_rev_parse_rules[] */
1868 if (!nr_rules) {
1869 size_t total_len = 0;
1871 /* the rule list is NULL terminated, count them first */
1872 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1873 /* no +1 because strlen("%s") < strlen("%.*s") */
1874 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1876 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1878 total_len = 0;
1879 for (i = 0; i < nr_rules; i++) {
1880 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1881 + total_len;
1882 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1883 total_len += strlen(ref_rev_parse_rules[i]);
1887 /* bail out if there are no rules */
1888 if (!nr_rules)
1889 return xstrdup(ref);
1891 /* buffer for scanf result, at most ref must fit */
1892 short_name = xstrdup(ref);
1894 /* skip first rule, it will always match */
1895 for (i = nr_rules - 1; i > 0 ; --i) {
1896 int j;
1897 int rules_to_fail = i;
1898 int short_name_len;
1900 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1901 continue;
1903 short_name_len = strlen(short_name);
1906 * in strict mode, all (except the matched one) rules
1907 * must fail to resolve to a valid non-ambiguous ref
1909 if (strict)
1910 rules_to_fail = nr_rules;
1913 * check if the short name resolves to a valid ref,
1914 * but use only rules prior to the matched one
1916 for (j = 0; j < rules_to_fail; j++) {
1917 const char *rule = ref_rev_parse_rules[j];
1918 unsigned char short_objectname[20];
1919 char refname[PATH_MAX];
1921 /* skip matched rule */
1922 if (i == j)
1923 continue;
1926 * the short name is ambiguous, if it resolves
1927 * (with this previous rule) to a valid ref
1928 * read_ref() returns 0 on success
1930 mksnpath(refname, sizeof(refname),
1931 rule, short_name_len, short_name);
1932 if (!read_ref(refname, short_objectname))
1933 break;
1937 * short name is non-ambiguous if all previous rules
1938 * haven't resolved to a valid ref
1940 if (j == rules_to_fail)
1941 return short_name;
1944 free(short_name);
1945 return xstrdup(ref);