Win32 dirent: remove unused dirent.d_reclen member
[git/dscho.git] / refs.c
blobb8843bb4769a2c5e3496d962f8d6b85a483fa92e
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
7 /* ISSYMREF=0x01, ISPACKED=0x02 and ISBROKEN=0x04 are public interfaces */
8 #define REF_KNOWS_PEELED 0x10
10 struct ref_entry {
11 unsigned char flag; /* ISSYMREF? ISPACKED? */
12 unsigned char sha1[20];
13 unsigned char peeled[20];
14 /* The full name of the reference (e.g., "refs/heads/master"): */
15 char name[FLEX_ARRAY];
18 struct ref_array {
19 int nr, alloc;
22 * Entries with index 0 <= i < sorted are sorted by name. New
23 * entries are appended to the list unsorted, and are sorted
24 * only when required; thus we avoid the need to sort the list
25 * after the addition of every reference.
27 int sorted;
29 struct ref_entry **refs;
33 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
34 * Return a pointer to the refname within the line (null-terminated),
35 * or NULL if there was a problem.
37 static const char *parse_ref_line(char *line, unsigned char *sha1)
40 * 42: the answer to everything.
42 * In this case, it happens to be the answer to
43 * 40 (length of sha1 hex representation)
44 * +1 (space in between hex and name)
45 * +1 (newline at the end of the line)
47 int len = strlen(line) - 42;
49 if (len <= 0)
50 return NULL;
51 if (get_sha1_hex(line, sha1) < 0)
52 return NULL;
53 if (!isspace(line[40]))
54 return NULL;
55 line += 41;
56 if (isspace(*line))
57 return NULL;
58 if (line[len] != '\n')
59 return NULL;
60 line[len] = 0;
62 return line;
65 static struct ref_entry *create_ref_entry(const char *refname,
66 const unsigned char *sha1, int flag,
67 int check_name)
69 int len;
70 struct ref_entry *ref;
72 if (check_name &&
73 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
74 die("Reference has invalid format: '%s'", refname);
75 len = strlen(refname) + 1;
76 ref = xmalloc(sizeof(struct ref_entry) + len);
77 hashcpy(ref->sha1, sha1);
78 hashclr(ref->peeled);
79 memcpy(ref->name, refname, len);
80 ref->flag = flag;
81 return ref;
84 /* Add a ref_entry to the end of the ref_array (unsorted). */
85 static void add_ref(struct ref_array *refs, struct ref_entry *ref)
87 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
88 refs->refs[refs->nr++] = ref;
91 static int ref_entry_cmp(const void *a, const void *b)
93 struct ref_entry *one = *(struct ref_entry **)a;
94 struct ref_entry *two = *(struct ref_entry **)b;
95 return strcmp(one->name, two->name);
99 * Emit a warning and return true iff ref1 and ref2 have the same name
100 * and the same sha1. Die if they have the same name but different
101 * sha1s.
103 static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
105 if (!strcmp(ref1->name, ref2->name)) {
106 /* Duplicate name; make sure that the SHA1s match: */
107 if (hashcmp(ref1->sha1, ref2->sha1))
108 die("Duplicated ref, and SHA1s don't match: %s",
109 ref1->name);
110 warning("Duplicated ref: %s", ref1->name);
111 return 1;
112 } else {
113 return 0;
118 * Sort the entries in array (if they are not already sorted).
120 static void sort_ref_array(struct ref_array *array)
122 int i, j;
125 * This check also prevents passing a zero-length array to qsort(),
126 * which is a problem on some platforms.
128 if (array->sorted == array->nr)
129 return;
131 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
133 /* Remove any duplicates from the ref_array */
134 i = 0;
135 for (j = 1; j < array->nr; j++) {
136 if (is_dup_ref(array->refs[i], array->refs[j])) {
137 free(array->refs[j]);
138 continue;
140 array->refs[++i] = array->refs[j];
142 array->sorted = array->nr = i + 1;
145 static struct ref_entry *search_ref_array(struct ref_array *array, const char *refname)
147 struct ref_entry *e, **r;
148 int len;
150 if (refname == NULL)
151 return NULL;
153 if (!array->nr)
154 return NULL;
155 sort_ref_array(array);
156 len = strlen(refname) + 1;
157 e = xmalloc(sizeof(struct ref_entry) + len);
158 memcpy(e->name, refname, len);
160 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
162 free(e);
164 if (r == NULL)
165 return NULL;
167 return *r;
171 * Future: need to be in "struct repository"
172 * when doing a full libification.
174 static struct ref_cache {
175 struct ref_cache *next;
176 char did_loose;
177 char did_packed;
178 struct ref_array loose;
179 struct ref_array packed;
180 /* The submodule name, or "" for the main repo. */
181 char name[FLEX_ARRAY];
182 } *ref_cache;
184 static struct ref_entry *current_ref;
187 * Never call sort_ref_array() on the extra_refs, because it is
188 * allowed to contain entries with duplicate names.
190 static struct ref_array extra_refs;
192 static void clear_ref_array(struct ref_array *array)
194 int i;
195 for (i = 0; i < array->nr; i++)
196 free(array->refs[i]);
197 free(array->refs);
198 array->sorted = array->nr = array->alloc = 0;
199 array->refs = NULL;
202 static void clear_packed_ref_cache(struct ref_cache *refs)
204 if (refs->did_packed)
205 clear_ref_array(&refs->packed);
206 refs->did_packed = 0;
209 static void clear_loose_ref_cache(struct ref_cache *refs)
211 if (refs->did_loose)
212 clear_ref_array(&refs->loose);
213 refs->did_loose = 0;
216 static struct ref_cache *create_ref_cache(const char *submodule)
218 int len;
219 struct ref_cache *refs;
220 if (!submodule)
221 submodule = "";
222 len = strlen(submodule) + 1;
223 refs = xcalloc(1, sizeof(struct ref_cache) + len);
224 memcpy(refs->name, submodule, len);
225 return refs;
229 * Return a pointer to a ref_cache for the specified submodule. For
230 * the main repository, use submodule==NULL. The returned structure
231 * will be allocated and initialized but not necessarily populated; it
232 * should not be freed.
234 static struct ref_cache *get_ref_cache(const char *submodule)
236 struct ref_cache *refs = ref_cache;
237 if (!submodule)
238 submodule = "";
239 while (refs) {
240 if (!strcmp(submodule, refs->name))
241 return refs;
242 refs = refs->next;
245 refs = create_ref_cache(submodule);
246 refs->next = ref_cache;
247 ref_cache = refs;
248 return refs;
251 void invalidate_ref_cache(const char *submodule)
253 struct ref_cache *refs = get_ref_cache(submodule);
254 clear_packed_ref_cache(refs);
255 clear_loose_ref_cache(refs);
258 static void read_packed_refs(FILE *f, struct ref_array *array)
260 struct ref_entry *last = NULL;
261 char refline[PATH_MAX];
262 int flag = REF_ISPACKED;
264 while (fgets(refline, sizeof(refline), f)) {
265 unsigned char sha1[20];
266 const char *refname;
267 static const char header[] = "# pack-refs with:";
269 if (!strncmp(refline, header, sizeof(header)-1)) {
270 const char *traits = refline + sizeof(header) - 1;
271 if (strstr(traits, " peeled "))
272 flag |= REF_KNOWS_PEELED;
273 /* perhaps other traits later as well */
274 continue;
277 refname = parse_ref_line(refline, sha1);
278 if (refname) {
279 last = create_ref_entry(refname, sha1, flag, 1);
280 add_ref(array, last);
281 continue;
283 if (last &&
284 refline[0] == '^' &&
285 strlen(refline) == 42 &&
286 refline[41] == '\n' &&
287 !get_sha1_hex(refline + 1, sha1))
288 hashcpy(last->peeled, sha1);
292 void add_extra_ref(const char *refname, const unsigned char *sha1, int flag)
294 add_ref(&extra_refs, create_ref_entry(refname, sha1, flag, 0));
297 void clear_extra_refs(void)
299 clear_ref_array(&extra_refs);
302 static struct ref_array *get_packed_refs(struct ref_cache *refs)
304 if (!refs->did_packed) {
305 const char *packed_refs_file;
306 FILE *f;
308 if (*refs->name)
309 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
310 else
311 packed_refs_file = git_path("packed-refs");
312 f = fopen(packed_refs_file, "r");
313 if (f) {
314 read_packed_refs(f, &refs->packed);
315 fclose(f);
317 refs->did_packed = 1;
319 return &refs->packed;
322 void add_packed_ref(const char *refname, const unsigned char *sha1)
324 add_ref(get_packed_refs(get_ref_cache(NULL)),
325 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
328 static void get_ref_dir(struct ref_cache *refs, const char *base,
329 struct ref_array *array)
331 DIR *dir;
332 const char *path;
334 if (*refs->name)
335 path = git_path_submodule(refs->name, "%s", base);
336 else
337 path = git_path("%s", base);
340 dir = opendir(path);
342 if (dir) {
343 struct dirent *de;
344 int baselen = strlen(base);
345 char *refname = xmalloc(baselen + 257);
347 memcpy(refname, base, baselen);
348 if (baselen && base[baselen-1] != '/')
349 refname[baselen++] = '/';
351 while ((de = readdir(dir)) != NULL) {
352 unsigned char sha1[20];
353 struct stat st;
354 int flag;
355 int namelen;
356 const char *refdir;
358 if (de->d_name[0] == '.')
359 continue;
360 namelen = strlen(de->d_name);
361 if (namelen > 255)
362 continue;
363 if (has_extension(de->d_name, ".lock"))
364 continue;
365 memcpy(refname + baselen, de->d_name, namelen+1);
366 refdir = *refs->name
367 ? git_path_submodule(refs->name, "%s", refname)
368 : git_path("%s", refname);
369 if (stat(refdir, &st) < 0)
370 continue;
371 if (S_ISDIR(st.st_mode)) {
372 get_ref_dir(refs, refname, array);
373 continue;
375 if (*refs->name) {
376 hashclr(sha1);
377 flag = 0;
378 if (resolve_gitlink_ref(refs->name, refname, sha1) < 0) {
379 hashclr(sha1);
380 flag |= REF_ISBROKEN;
382 } else if (read_ref_full(refname, sha1, 1, &flag)) {
383 hashclr(sha1);
384 flag |= REF_ISBROKEN;
386 add_ref(array, create_ref_entry(refname, sha1, flag, 1));
388 free(refname);
389 closedir(dir);
393 struct warn_if_dangling_data {
394 FILE *fp;
395 const char *refname;
396 const char *msg_fmt;
399 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
400 int flags, void *cb_data)
402 struct warn_if_dangling_data *d = cb_data;
403 const char *resolves_to;
404 unsigned char junk[20];
406 if (!(flags & REF_ISSYMREF))
407 return 0;
409 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
410 if (!resolves_to || strcmp(resolves_to, d->refname))
411 return 0;
413 fprintf(d->fp, d->msg_fmt, refname);
414 return 0;
417 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
419 struct warn_if_dangling_data data;
421 data.fp = fp;
422 data.refname = refname;
423 data.msg_fmt = msg_fmt;
424 for_each_rawref(warn_if_dangling_symref, &data);
427 static struct ref_array *get_loose_refs(struct ref_cache *refs)
429 if (!refs->did_loose) {
430 get_ref_dir(refs, "refs", &refs->loose);
431 refs->did_loose = 1;
433 return &refs->loose;
436 /* We allow "recursive" symbolic refs. Only within reason, though */
437 #define MAXDEPTH 5
438 #define MAXREFLEN (1024)
441 * Called by resolve_gitlink_ref_recursive() after it failed to read
442 * from the loose refs in ref_cache refs. Find <refname> in the
443 * packed-refs file for the submodule.
445 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
446 const char *refname, unsigned char *sha1)
448 struct ref_entry *ref;
449 struct ref_array *array = get_packed_refs(refs);
451 ref = search_ref_array(array, refname);
452 if (ref == NULL)
453 return -1;
455 memcpy(sha1, ref->sha1, 20);
456 return 0;
459 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
460 const char *refname, unsigned char *sha1,
461 int recursion)
463 int fd, len;
464 char buffer[128], *p;
465 char *path;
467 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
468 return -1;
469 path = *refs->name
470 ? git_path_submodule(refs->name, "%s", refname)
471 : git_path("%s", refname);
472 fd = open(path, O_RDONLY);
473 if (fd < 0)
474 return resolve_gitlink_packed_ref(refs, refname, sha1);
476 len = read(fd, buffer, sizeof(buffer)-1);
477 close(fd);
478 if (len < 0)
479 return -1;
480 while (len && isspace(buffer[len-1]))
481 len--;
482 buffer[len] = 0;
484 /* Was it a detached head or an old-fashioned symlink? */
485 if (!get_sha1_hex(buffer, sha1))
486 return 0;
488 /* Symref? */
489 if (strncmp(buffer, "ref:", 4))
490 return -1;
491 p = buffer + 4;
492 while (isspace(*p))
493 p++;
495 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
498 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
500 int len = strlen(path), retval;
501 char *submodule;
502 struct ref_cache *refs;
504 while (len && path[len-1] == '/')
505 len--;
506 if (!len)
507 return -1;
508 submodule = xstrndup(path, len);
509 refs = get_ref_cache(submodule);
510 free(submodule);
512 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
513 return retval;
517 * Try to read ref from the packed references. On success, set sha1
518 * and return 0; otherwise, return -1.
520 static int get_packed_ref(const char *refname, unsigned char *sha1)
522 struct ref_array *packed = get_packed_refs(get_ref_cache(NULL));
523 struct ref_entry *entry = search_ref_array(packed, refname);
524 if (entry) {
525 hashcpy(sha1, entry->sha1);
526 return 0;
528 return -1;
531 const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
533 int depth = MAXDEPTH;
534 ssize_t len;
535 char buffer[256];
536 static char refname_buffer[256];
538 if (flag)
539 *flag = 0;
541 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
542 return NULL;
544 for (;;) {
545 char path[PATH_MAX];
546 struct stat st;
547 char *buf;
548 int fd;
550 if (--depth < 0)
551 return NULL;
553 git_snpath(path, sizeof(path), "%s", refname);
555 if (lstat(path, &st) < 0) {
556 if (errno != ENOENT)
557 return NULL;
559 * The loose reference file does not exist;
560 * check for a packed reference.
562 if (!get_packed_ref(refname, sha1)) {
563 if (flag)
564 *flag |= REF_ISPACKED;
565 return refname;
567 /* The reference is not a packed reference, either. */
568 if (reading) {
569 return NULL;
570 } else {
571 hashclr(sha1);
572 return refname;
576 /* Follow "normalized" - ie "refs/.." symlinks by hand */
577 if (S_ISLNK(st.st_mode)) {
578 len = readlink(path, buffer, sizeof(buffer)-1);
579 if (len < 0)
580 return NULL;
581 buffer[len] = 0;
582 if (!prefixcmp(buffer, "refs/") &&
583 !check_refname_format(buffer, 0)) {
584 strcpy(refname_buffer, buffer);
585 refname = refname_buffer;
586 if (flag)
587 *flag |= REF_ISSYMREF;
588 continue;
592 /* Is it a directory? */
593 if (S_ISDIR(st.st_mode)) {
594 errno = EISDIR;
595 return NULL;
599 * Anything else, just open it and try to use it as
600 * a ref
602 fd = open(path, O_RDONLY);
603 if (fd < 0)
604 return NULL;
605 len = read_in_full(fd, buffer, sizeof(buffer)-1);
606 close(fd);
607 if (len < 0)
608 return NULL;
609 while (len && isspace(buffer[len-1]))
610 len--;
611 buffer[len] = '\0';
614 * Is it a symbolic ref?
616 if (prefixcmp(buffer, "ref:"))
617 break;
618 if (flag)
619 *flag |= REF_ISSYMREF;
620 buf = buffer + 4;
621 while (isspace(*buf))
622 buf++;
623 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
624 if (flag)
625 *flag |= REF_ISBROKEN;
626 return NULL;
628 refname = strcpy(refname_buffer, buf);
630 /* Please note that FETCH_HEAD has a second line containing other data. */
631 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
632 if (flag)
633 *flag |= REF_ISBROKEN;
634 return NULL;
636 return refname;
639 char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
641 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
642 return ret ? xstrdup(ret) : NULL;
645 /* The argument to filter_refs */
646 struct ref_filter {
647 const char *pattern;
648 each_ref_fn *fn;
649 void *cb_data;
652 int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
654 if (resolve_ref_unsafe(refname, sha1, reading, flags))
655 return 0;
656 return -1;
659 int read_ref(const char *refname, unsigned char *sha1)
661 return read_ref_full(refname, sha1, 1, NULL);
664 #define DO_FOR_EACH_INCLUDE_BROKEN 01
665 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
666 int flags, void *cb_data, struct ref_entry *entry)
668 if (prefixcmp(entry->name, base))
669 return 0;
671 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
672 if (entry->flag & REF_ISBROKEN)
673 return 0; /* ignore broken refs e.g. dangling symref */
674 if (!has_sha1_file(entry->sha1)) {
675 error("%s does not point to a valid object!", entry->name);
676 return 0;
679 current_ref = entry;
680 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
683 static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
684 void *data)
686 struct ref_filter *filter = (struct ref_filter *)data;
687 if (fnmatch(filter->pattern, refname, 0))
688 return 0;
689 return filter->fn(refname, sha1, flags, filter->cb_data);
692 int peel_ref(const char *refname, unsigned char *sha1)
694 int flag;
695 unsigned char base[20];
696 struct object *o;
698 if (current_ref && (current_ref->name == refname
699 || !strcmp(current_ref->name, refname))) {
700 if (current_ref->flag & REF_KNOWS_PEELED) {
701 hashcpy(sha1, current_ref->peeled);
702 return 0;
704 hashcpy(base, current_ref->sha1);
705 goto fallback;
708 if (read_ref_full(refname, base, 1, &flag))
709 return -1;
711 if ((flag & REF_ISPACKED)) {
712 struct ref_array *array = get_packed_refs(get_ref_cache(NULL));
713 struct ref_entry *r = search_ref_array(array, refname);
715 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
716 hashcpy(sha1, r->peeled);
717 return 0;
721 fallback:
722 o = parse_object(base);
723 if (o && o->type == OBJ_TAG) {
724 o = deref_tag(o, refname, 0);
725 if (o) {
726 hashcpy(sha1, o->sha1);
727 return 0;
730 return -1;
733 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
734 int trim, int flags, void *cb_data)
736 int retval = 0, i, p = 0, l = 0;
737 struct ref_cache *refs = get_ref_cache(submodule);
738 struct ref_array *packed = get_packed_refs(refs);
739 struct ref_array *loose = get_loose_refs(refs);
741 struct ref_array *extra = &extra_refs;
743 for (i = 0; i < extra->nr; i++)
744 retval = do_one_ref(base, fn, trim, flags, cb_data, extra->refs[i]);
746 sort_ref_array(packed);
747 sort_ref_array(loose);
748 while (p < packed->nr && l < loose->nr) {
749 struct ref_entry *entry;
750 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
751 if (!cmp) {
752 p++;
753 continue;
755 if (cmp > 0) {
756 entry = loose->refs[l++];
757 } else {
758 entry = packed->refs[p++];
760 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
761 if (retval)
762 goto end_each;
765 if (l < loose->nr) {
766 p = l;
767 packed = loose;
770 for (; p < packed->nr; p++) {
771 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
772 if (retval)
773 goto end_each;
776 end_each:
777 current_ref = NULL;
778 return retval;
782 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
784 unsigned char sha1[20];
785 int flag;
787 if (submodule) {
788 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
789 return fn("HEAD", sha1, 0, cb_data);
791 return 0;
794 if (!read_ref_full("HEAD", sha1, 1, &flag))
795 return fn("HEAD", sha1, flag, cb_data);
797 return 0;
800 int head_ref(each_ref_fn fn, void *cb_data)
802 return do_head_ref(NULL, fn, cb_data);
805 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
807 return do_head_ref(submodule, fn, cb_data);
810 int for_each_ref(each_ref_fn fn, void *cb_data)
812 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
815 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
817 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
820 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
822 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
825 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
826 each_ref_fn fn, void *cb_data)
828 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
831 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
833 return for_each_ref_in("refs/tags/", fn, cb_data);
836 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
838 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
841 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
843 return for_each_ref_in("refs/heads/", fn, cb_data);
846 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
848 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
851 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
853 return for_each_ref_in("refs/remotes/", fn, cb_data);
856 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
858 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
861 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
863 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
866 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
868 struct strbuf buf = STRBUF_INIT;
869 int ret = 0;
870 unsigned char sha1[20];
871 int flag;
873 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
874 if (!read_ref_full(buf.buf, sha1, 1, &flag))
875 ret = fn(buf.buf, sha1, flag, cb_data);
876 strbuf_release(&buf);
878 return ret;
881 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
883 struct strbuf buf = STRBUF_INIT;
884 int ret;
885 strbuf_addf(&buf, "%srefs/", get_git_namespace());
886 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
887 strbuf_release(&buf);
888 return ret;
891 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
892 const char *prefix, void *cb_data)
894 struct strbuf real_pattern = STRBUF_INIT;
895 struct ref_filter filter;
896 int ret;
898 if (!prefix && prefixcmp(pattern, "refs/"))
899 strbuf_addstr(&real_pattern, "refs/");
900 else if (prefix)
901 strbuf_addstr(&real_pattern, prefix);
902 strbuf_addstr(&real_pattern, pattern);
904 if (!has_glob_specials(pattern)) {
905 /* Append implied '/' '*' if not present. */
906 if (real_pattern.buf[real_pattern.len - 1] != '/')
907 strbuf_addch(&real_pattern, '/');
908 /* No need to check for '*', there is none. */
909 strbuf_addch(&real_pattern, '*');
912 filter.pattern = real_pattern.buf;
913 filter.fn = fn;
914 filter.cb_data = cb_data;
915 ret = for_each_ref(filter_refs, &filter);
917 strbuf_release(&real_pattern);
918 return ret;
921 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
923 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
926 int for_each_rawref(each_ref_fn fn, void *cb_data)
928 return do_for_each_ref(NULL, "", fn, 0,
929 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
933 * Make sure "ref" is something reasonable to have under ".git/refs/";
934 * We do not like it if:
936 * - any path component of it begins with ".", or
937 * - it has double dots "..", or
938 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
939 * - it ends with a "/".
940 * - it ends with ".lock"
941 * - it contains a "\" (backslash)
944 /* Return true iff ch is not allowed in reference names. */
945 static inline int bad_ref_char(int ch)
947 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
948 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
949 return 1;
950 /* 2.13 Pattern Matching Notation */
951 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
952 return 1;
953 return 0;
957 * Try to read one refname component from the front of refname. Return
958 * the length of the component found, or -1 if the component is not
959 * legal.
961 static int check_refname_component(const char *refname, int flags)
963 const char *cp;
964 char last = '\0';
966 for (cp = refname; ; cp++) {
967 char ch = *cp;
968 if (ch == '\0' || ch == '/')
969 break;
970 if (bad_ref_char(ch))
971 return -1; /* Illegal character in refname. */
972 if (last == '.' && ch == '.')
973 return -1; /* Refname contains "..". */
974 if (last == '@' && ch == '{')
975 return -1; /* Refname contains "@{". */
976 last = ch;
978 if (cp == refname)
979 return -1; /* Component has zero length. */
980 if (refname[0] == '.') {
981 if (!(flags & REFNAME_DOT_COMPONENT))
982 return -1; /* Component starts with '.'. */
984 * Even if leading dots are allowed, don't allow "."
985 * as a component (".." is prevented by a rule above).
987 if (refname[1] == '\0')
988 return -1; /* Component equals ".". */
990 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
991 return -1; /* Refname ends with ".lock". */
992 return cp - refname;
995 int check_refname_format(const char *refname, int flags)
997 int component_len, component_count = 0;
999 while (1) {
1000 /* We are at the start of a path component. */
1001 component_len = check_refname_component(refname, flags);
1002 if (component_len < 0) {
1003 if ((flags & REFNAME_REFSPEC_PATTERN) &&
1004 refname[0] == '*' &&
1005 (refname[1] == '\0' || refname[1] == '/')) {
1006 /* Accept one wildcard as a full refname component. */
1007 flags &= ~REFNAME_REFSPEC_PATTERN;
1008 component_len = 1;
1009 } else {
1010 return -1;
1013 component_count++;
1014 if (refname[component_len] == '\0')
1015 break;
1016 /* Skip to next component. */
1017 refname += component_len + 1;
1020 if (refname[component_len - 1] == '.')
1021 return -1; /* Refname ends with '.'. */
1022 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
1023 return -1; /* Refname has only one component. */
1024 return 0;
1027 const char *prettify_refname(const char *name)
1029 return name + (
1030 !prefixcmp(name, "refs/heads/") ? 11 :
1031 !prefixcmp(name, "refs/tags/") ? 10 :
1032 !prefixcmp(name, "refs/remotes/") ? 13 :
1036 const char *ref_rev_parse_rules[] = {
1037 "%.*s",
1038 "refs/%.*s",
1039 "refs/tags/%.*s",
1040 "refs/heads/%.*s",
1041 "refs/remotes/%.*s",
1042 "refs/remotes/%.*s/HEAD",
1043 NULL
1046 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1048 const char **p;
1049 const int abbrev_name_len = strlen(abbrev_name);
1051 for (p = rules; *p; p++) {
1052 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1053 return 1;
1057 return 0;
1060 static struct ref_lock *verify_lock(struct ref_lock *lock,
1061 const unsigned char *old_sha1, int mustexist)
1063 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1064 error("Can't verify ref %s", lock->ref_name);
1065 unlock_ref(lock);
1066 return NULL;
1068 if (hashcmp(lock->old_sha1, old_sha1)) {
1069 error("Ref %s is at %s but expected %s", lock->ref_name,
1070 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1071 unlock_ref(lock);
1072 return NULL;
1074 return lock;
1077 static int remove_empty_directories(const char *file)
1079 /* we want to create a file but there is a directory there;
1080 * if that is an empty directory (or a directory that contains
1081 * only empty directories), remove them.
1083 struct strbuf path;
1084 int result;
1086 strbuf_init(&path, 20);
1087 strbuf_addstr(&path, file);
1089 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1091 strbuf_release(&path);
1093 return result;
1097 * Return true iff a reference named refname could be created without
1098 * conflicting with the name of an existing reference. If oldrefname
1099 * is non-NULL, ignore potential conflicts with oldrefname (e.g.,
1100 * because oldrefname is scheduled for deletion in the same
1101 * operation).
1103 static int is_refname_available(const char *refname, const char *oldrefname,
1104 struct ref_array *array)
1106 int i, namlen = strlen(refname); /* e.g. 'foo/bar' */
1107 for (i = 0; i < array->nr; i++ ) {
1108 struct ref_entry *entry = array->refs[i];
1109 /* entry->name could be 'foo' or 'foo/bar/baz' */
1110 if (!oldrefname || strcmp(oldrefname, entry->name)) {
1111 int len = strlen(entry->name);
1112 int cmplen = (namlen < len) ? namlen : len;
1113 const char *lead = (namlen < len) ? entry->name : refname;
1114 if (!strncmp(refname, entry->name, cmplen) &&
1115 lead[cmplen] == '/') {
1116 error("'%s' exists; cannot create '%s'",
1117 entry->name, refname);
1118 return 0;
1122 return 1;
1126 * *string and *len will only be substituted, and *string returned (for
1127 * later free()ing) if the string passed in is a magic short-hand form
1128 * to name a branch.
1130 static char *substitute_branch_name(const char **string, int *len)
1132 struct strbuf buf = STRBUF_INIT;
1133 int ret = interpret_branch_name(*string, &buf);
1135 if (ret == *len) {
1136 size_t size;
1137 *string = strbuf_detach(&buf, &size);
1138 *len = size;
1139 return (char *)*string;
1142 return NULL;
1145 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1147 char *last_branch = substitute_branch_name(&str, &len);
1148 const char **p, *r;
1149 int refs_found = 0;
1151 *ref = NULL;
1152 for (p = ref_rev_parse_rules; *p; p++) {
1153 char fullref[PATH_MAX];
1154 unsigned char sha1_from_ref[20];
1155 unsigned char *this_result;
1156 int flag;
1158 this_result = refs_found ? sha1_from_ref : sha1;
1159 mksnpath(fullref, sizeof(fullref), *p, len, str);
1160 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
1161 if (r) {
1162 if (!refs_found++)
1163 *ref = xstrdup(r);
1164 if (!warn_ambiguous_refs)
1165 break;
1166 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1167 warning("ignoring dangling symref %s.", fullref);
1168 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1169 warning("ignoring broken ref %s.", fullref);
1172 free(last_branch);
1173 return refs_found;
1176 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1178 char *last_branch = substitute_branch_name(&str, &len);
1179 const char **p;
1180 int logs_found = 0;
1182 *log = NULL;
1183 for (p = ref_rev_parse_rules; *p; p++) {
1184 struct stat st;
1185 unsigned char hash[20];
1186 char path[PATH_MAX];
1187 const char *ref, *it;
1189 mksnpath(path, sizeof(path), *p, len, str);
1190 ref = resolve_ref_unsafe(path, hash, 1, NULL);
1191 if (!ref)
1192 continue;
1193 if (!stat(git_path("logs/%s", path), &st) &&
1194 S_ISREG(st.st_mode))
1195 it = path;
1196 else if (strcmp(ref, path) &&
1197 !stat(git_path("logs/%s", ref), &st) &&
1198 S_ISREG(st.st_mode))
1199 it = ref;
1200 else
1201 continue;
1202 if (!logs_found++) {
1203 *log = xstrdup(it);
1204 hashcpy(sha1, hash);
1206 if (!warn_ambiguous_refs)
1207 break;
1209 free(last_branch);
1210 return logs_found;
1213 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1214 const unsigned char *old_sha1,
1215 int flags, int *type_p)
1217 char *ref_file;
1218 const char *orig_refname = refname;
1219 struct ref_lock *lock;
1220 int last_errno = 0;
1221 int type, lflags;
1222 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1223 int missing = 0;
1225 lock = xcalloc(1, sizeof(struct ref_lock));
1226 lock->lock_fd = -1;
1228 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
1229 if (!refname && errno == EISDIR) {
1230 /* we are trying to lock foo but we used to
1231 * have foo/bar which now does not exist;
1232 * it is normal for the empty directory 'foo'
1233 * to remain.
1235 ref_file = git_path("%s", orig_refname);
1236 if (remove_empty_directories(ref_file)) {
1237 last_errno = errno;
1238 error("there are still refs under '%s'", orig_refname);
1239 goto error_return;
1241 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
1243 if (type_p)
1244 *type_p = type;
1245 if (!refname) {
1246 last_errno = errno;
1247 error("unable to resolve reference %s: %s",
1248 orig_refname, strerror(errno));
1249 goto error_return;
1251 missing = is_null_sha1(lock->old_sha1);
1252 /* When the ref did not exist and we are creating it,
1253 * make sure there is no existing ref that is packed
1254 * whose name begins with our refname, nor a ref whose
1255 * name is a proper prefix of our refname.
1257 if (missing &&
1258 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
1259 last_errno = ENOTDIR;
1260 goto error_return;
1263 lock->lk = xcalloc(1, sizeof(struct lock_file));
1265 lflags = LOCK_DIE_ON_ERROR;
1266 if (flags & REF_NODEREF) {
1267 refname = orig_refname;
1268 lflags |= LOCK_NODEREF;
1270 lock->ref_name = xstrdup(refname);
1271 lock->orig_ref_name = xstrdup(orig_refname);
1272 ref_file = git_path("%s", refname);
1273 if (missing)
1274 lock->force_write = 1;
1275 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1276 lock->force_write = 1;
1278 if (safe_create_leading_directories(ref_file)) {
1279 last_errno = errno;
1280 error("unable to create directory for %s", ref_file);
1281 goto error_return;
1284 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1285 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1287 error_return:
1288 unlock_ref(lock);
1289 errno = last_errno;
1290 return NULL;
1293 struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
1295 char refpath[PATH_MAX];
1296 if (check_refname_format(refname, 0))
1297 return NULL;
1298 strcpy(refpath, mkpath("refs/%s", refname));
1299 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1302 struct ref_lock *lock_any_ref_for_update(const char *refname,
1303 const unsigned char *old_sha1, int flags)
1305 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1306 return NULL;
1307 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
1310 static struct lock_file packlock;
1312 static int repack_without_ref(const char *refname)
1314 struct ref_array *packed;
1315 int fd, i;
1317 packed = get_packed_refs(get_ref_cache(NULL));
1318 if (search_ref_array(packed, refname) == NULL)
1319 return 0;
1320 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1321 if (fd < 0) {
1322 unable_to_lock_error(git_path("packed-refs"), errno);
1323 return error("cannot delete '%s' from packed refs", refname);
1326 for (i = 0; i < packed->nr; i++) {
1327 char line[PATH_MAX + 100];
1328 int len;
1329 struct ref_entry *ref = packed->refs[i];
1331 if (!strcmp(refname, ref->name))
1332 continue;
1333 len = snprintf(line, sizeof(line), "%s %s\n",
1334 sha1_to_hex(ref->sha1), ref->name);
1335 /* this should not happen but just being defensive */
1336 if (len > sizeof(line))
1337 die("too long a refname '%s'", ref->name);
1338 write_or_die(fd, line, len);
1340 return commit_lock_file(&packlock);
1343 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1345 struct ref_lock *lock;
1346 int err, i = 0, ret = 0, flag = 0;
1348 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1349 if (!lock)
1350 return 1;
1351 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1352 /* loose */
1353 const char *path;
1355 if (!(delopt & REF_NODEREF)) {
1356 i = strlen(lock->lk->filename) - 5; /* .lock */
1357 lock->lk->filename[i] = 0;
1358 path = lock->lk->filename;
1359 } else {
1360 path = git_path("%s", refname);
1362 err = unlink_or_warn(path);
1363 if (err && errno != ENOENT)
1364 ret = 1;
1366 if (!(delopt & REF_NODEREF))
1367 lock->lk->filename[i] = '.';
1369 /* removing the loose one could have resurrected an earlier
1370 * packed one. Also, if it was not loose we need to repack
1371 * without it.
1373 ret |= repack_without_ref(refname);
1375 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1376 invalidate_ref_cache(NULL);
1377 unlock_ref(lock);
1378 return ret;
1382 * People using contrib's git-new-workdir have .git/logs/refs ->
1383 * /some/other/path/.git/logs/refs, and that may live on another device.
1385 * IOW, to avoid cross device rename errors, the temporary renamed log must
1386 * live into logs/refs.
1388 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1390 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
1392 unsigned char sha1[20], orig_sha1[20];
1393 int flag = 0, logmoved = 0;
1394 struct ref_lock *lock;
1395 struct stat loginfo;
1396 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
1397 const char *symref = NULL;
1398 struct ref_cache *refs = get_ref_cache(NULL);
1400 if (log && S_ISLNK(loginfo.st_mode))
1401 return error("reflog for %s is a symlink", oldrefname);
1403 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
1404 if (flag & REF_ISSYMREF)
1405 return error("refname %s is a symbolic ref, renaming it is not supported",
1406 oldrefname);
1407 if (!symref)
1408 return error("refname %s not found", oldrefname);
1410 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
1411 return 1;
1413 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
1414 return 1;
1416 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
1417 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1418 oldrefname, strerror(errno));
1420 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1421 error("unable to delete old %s", oldrefname);
1422 goto rollback;
1425 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1426 delete_ref(newrefname, sha1, REF_NODEREF)) {
1427 if (errno==EISDIR) {
1428 if (remove_empty_directories(git_path("%s", newrefname))) {
1429 error("Directory not empty: %s", newrefname);
1430 goto rollback;
1432 } else {
1433 error("unable to delete existing %s", newrefname);
1434 goto rollback;
1438 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1439 error("unable to create directory for %s", newrefname);
1440 goto rollback;
1443 retry:
1444 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
1445 if (errno==EISDIR || errno==ENOTDIR) {
1447 * rename(a, b) when b is an existing
1448 * directory ought to result in ISDIR, but
1449 * Solaris 5.8 gives ENOTDIR. Sheesh.
1451 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1452 error("Directory not empty: logs/%s", newrefname);
1453 goto rollback;
1455 goto retry;
1456 } else {
1457 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1458 newrefname, strerror(errno));
1459 goto rollback;
1462 logmoved = log;
1464 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
1465 if (!lock) {
1466 error("unable to lock %s for update", newrefname);
1467 goto rollback;
1469 lock->force_write = 1;
1470 hashcpy(lock->old_sha1, orig_sha1);
1471 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1472 error("unable to write current sha1 into %s", newrefname);
1473 goto rollback;
1476 return 0;
1478 rollback:
1479 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
1480 if (!lock) {
1481 error("unable to lock %s for rollback", oldrefname);
1482 goto rollbacklog;
1485 lock->force_write = 1;
1486 flag = log_all_ref_updates;
1487 log_all_ref_updates = 0;
1488 if (write_ref_sha1(lock, orig_sha1, NULL))
1489 error("unable to write current sha1 into %s", oldrefname);
1490 log_all_ref_updates = flag;
1492 rollbacklog:
1493 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
1494 error("unable to restore logfile %s from %s: %s",
1495 oldrefname, newrefname, strerror(errno));
1496 if (!logmoved && log &&
1497 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
1498 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1499 oldrefname, strerror(errno));
1501 return 1;
1504 int close_ref(struct ref_lock *lock)
1506 if (close_lock_file(lock->lk))
1507 return -1;
1508 lock->lock_fd = -1;
1509 return 0;
1512 int commit_ref(struct ref_lock *lock)
1514 if (commit_lock_file(lock->lk))
1515 return -1;
1516 lock->lock_fd = -1;
1517 return 0;
1520 void unlock_ref(struct ref_lock *lock)
1522 /* Do not free lock->lk -- atexit() still looks at them */
1523 if (lock->lk)
1524 rollback_lock_file(lock->lk);
1525 free(lock->ref_name);
1526 free(lock->orig_ref_name);
1527 free(lock);
1531 * copy the reflog message msg to buf, which has been allocated sufficiently
1532 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1533 * because reflog file is one line per entry.
1535 static int copy_msg(char *buf, const char *msg)
1537 char *cp = buf;
1538 char c;
1539 int wasspace = 1;
1541 *cp++ = '\t';
1542 while ((c = *msg++)) {
1543 if (wasspace && isspace(c))
1544 continue;
1545 wasspace = isspace(c);
1546 if (wasspace)
1547 c = ' ';
1548 *cp++ = c;
1550 while (buf < cp && isspace(cp[-1]))
1551 cp--;
1552 *cp++ = '\n';
1553 return cp - buf;
1556 int log_ref_setup(const char *refname, char *logfile, int bufsize)
1558 int logfd, oflags = O_APPEND | O_WRONLY;
1560 git_snpath(logfile, bufsize, "logs/%s", refname);
1561 if (log_all_ref_updates &&
1562 (!prefixcmp(refname, "refs/heads/") ||
1563 !prefixcmp(refname, "refs/remotes/") ||
1564 !prefixcmp(refname, "refs/notes/") ||
1565 !strcmp(refname, "HEAD"))) {
1566 if (safe_create_leading_directories(logfile) < 0)
1567 return error("unable to create directory for %s",
1568 logfile);
1569 oflags |= O_CREAT;
1572 logfd = open(logfile, oflags, 0666);
1573 if (logfd < 0) {
1574 if (!(oflags & O_CREAT) && errno == ENOENT)
1575 return 0;
1577 if ((oflags & O_CREAT) && errno == EISDIR) {
1578 if (remove_empty_directories(logfile)) {
1579 return error("There are still logs under '%s'",
1580 logfile);
1582 logfd = open(logfile, oflags, 0666);
1585 if (logfd < 0)
1586 return error("Unable to append to %s: %s",
1587 logfile, strerror(errno));
1590 adjust_shared_perm(logfile);
1591 close(logfd);
1592 return 0;
1595 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
1596 const unsigned char *new_sha1, const char *msg)
1598 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1599 unsigned maxlen, len;
1600 int msglen;
1601 char log_file[PATH_MAX];
1602 char *logrec;
1603 const char *committer;
1605 if (log_all_ref_updates < 0)
1606 log_all_ref_updates = !is_bare_repository();
1608 result = log_ref_setup(refname, log_file, sizeof(log_file));
1609 if (result)
1610 return result;
1612 logfd = open(log_file, oflags);
1613 if (logfd < 0)
1614 return 0;
1615 msglen = msg ? strlen(msg) : 0;
1616 committer = git_committer_info(0);
1617 maxlen = strlen(committer) + msglen + 100;
1618 logrec = xmalloc(maxlen);
1619 len = sprintf(logrec, "%s %s %s\n",
1620 sha1_to_hex(old_sha1),
1621 sha1_to_hex(new_sha1),
1622 committer);
1623 if (msglen)
1624 len += copy_msg(logrec + len - 1, msg) - 1;
1625 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1626 free(logrec);
1627 if (close(logfd) != 0 || written != len)
1628 return error("Unable to append to %s", log_file);
1629 return 0;
1632 static int is_branch(const char *refname)
1634 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1637 int write_ref_sha1(struct ref_lock *lock,
1638 const unsigned char *sha1, const char *logmsg)
1640 static char term = '\n';
1641 struct object *o;
1643 if (!lock)
1644 return -1;
1645 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1646 unlock_ref(lock);
1647 return 0;
1649 o = parse_object(sha1);
1650 if (!o) {
1651 error("Trying to write ref %s with nonexistent object %s",
1652 lock->ref_name, sha1_to_hex(sha1));
1653 unlock_ref(lock);
1654 return -1;
1656 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1657 error("Trying to write non-commit object %s to branch %s",
1658 sha1_to_hex(sha1), lock->ref_name);
1659 unlock_ref(lock);
1660 return -1;
1662 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1663 write_in_full(lock->lock_fd, &term, 1) != 1
1664 || close_ref(lock) < 0) {
1665 error("Couldn't write %s", lock->lk->filename);
1666 unlock_ref(lock);
1667 return -1;
1669 clear_loose_ref_cache(get_ref_cache(NULL));
1670 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1671 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1672 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1673 unlock_ref(lock);
1674 return -1;
1676 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1678 * Special hack: If a branch is updated directly and HEAD
1679 * points to it (may happen on the remote side of a push
1680 * for example) then logically the HEAD reflog should be
1681 * updated too.
1682 * A generic solution implies reverse symref information,
1683 * but finding all symrefs pointing to the given branch
1684 * would be rather costly for this rare event (the direct
1685 * update of a branch) to be worth it. So let's cheat and
1686 * check with HEAD only which should cover 99% of all usage
1687 * scenarios (even 100% of the default ones).
1689 unsigned char head_sha1[20];
1690 int head_flag;
1691 const char *head_ref;
1692 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
1693 if (head_ref && (head_flag & REF_ISSYMREF) &&
1694 !strcmp(head_ref, lock->ref_name))
1695 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1697 if (commit_ref(lock)) {
1698 error("Couldn't set %s", lock->ref_name);
1699 unlock_ref(lock);
1700 return -1;
1702 unlock_ref(lock);
1703 return 0;
1706 int create_symref(const char *ref_target, const char *refs_heads_master,
1707 const char *logmsg)
1709 const char *lockpath;
1710 char ref[1000];
1711 int fd, len, written;
1712 char *git_HEAD = git_pathdup("%s", ref_target);
1713 unsigned char old_sha1[20], new_sha1[20];
1715 if (logmsg && read_ref(ref_target, old_sha1))
1716 hashclr(old_sha1);
1718 if (safe_create_leading_directories(git_HEAD) < 0)
1719 return error("unable to create directory for %s", git_HEAD);
1721 #ifndef NO_SYMLINK_HEAD
1722 if (prefer_symlink_refs) {
1723 unlink(git_HEAD);
1724 if (!symlink(refs_heads_master, git_HEAD))
1725 goto done;
1726 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1728 #endif
1730 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1731 if (sizeof(ref) <= len) {
1732 error("refname too long: %s", refs_heads_master);
1733 goto error_free_return;
1735 lockpath = mkpath("%s.lock", git_HEAD);
1736 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1737 if (fd < 0) {
1738 error("Unable to open %s for writing", lockpath);
1739 goto error_free_return;
1741 written = write_in_full(fd, ref, len);
1742 if (close(fd) != 0 || written != len) {
1743 error("Unable to write to %s", lockpath);
1744 goto error_unlink_return;
1746 if (rename(lockpath, git_HEAD) < 0) {
1747 error("Unable to create %s", git_HEAD);
1748 goto error_unlink_return;
1750 if (adjust_shared_perm(git_HEAD)) {
1751 error("Unable to fix permissions on %s", lockpath);
1752 error_unlink_return:
1753 unlink_or_warn(lockpath);
1754 error_free_return:
1755 free(git_HEAD);
1756 return -1;
1759 #ifndef NO_SYMLINK_HEAD
1760 done:
1761 #endif
1762 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1763 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1765 free(git_HEAD);
1766 return 0;
1769 static char *ref_msg(const char *line, const char *endp)
1771 const char *ep;
1772 line += 82;
1773 ep = memchr(line, '\n', endp - line);
1774 if (!ep)
1775 ep = endp;
1776 return xmemdupz(line, ep - line);
1779 int read_ref_at(const char *refname, unsigned long at_time, int cnt,
1780 unsigned char *sha1, char **msg,
1781 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1783 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1784 char *tz_c;
1785 int logfd, tz, reccnt = 0;
1786 struct stat st;
1787 unsigned long date;
1788 unsigned char logged_sha1[20];
1789 void *log_mapped;
1790 size_t mapsz;
1792 logfile = git_path("logs/%s", refname);
1793 logfd = open(logfile, O_RDONLY, 0);
1794 if (logfd < 0)
1795 die_errno("Unable to read log '%s'", logfile);
1796 fstat(logfd, &st);
1797 if (!st.st_size)
1798 die("Log %s is empty.", logfile);
1799 mapsz = xsize_t(st.st_size);
1800 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1801 logdata = log_mapped;
1802 close(logfd);
1804 lastrec = NULL;
1805 rec = logend = logdata + st.st_size;
1806 while (logdata < rec) {
1807 reccnt++;
1808 if (logdata < rec && *(rec-1) == '\n')
1809 rec--;
1810 lastgt = NULL;
1811 while (logdata < rec && *(rec-1) != '\n') {
1812 rec--;
1813 if (*rec == '>')
1814 lastgt = rec;
1816 if (!lastgt)
1817 die("Log %s is corrupt.", logfile);
1818 date = strtoul(lastgt + 1, &tz_c, 10);
1819 if (date <= at_time || cnt == 0) {
1820 tz = strtoul(tz_c, NULL, 10);
1821 if (msg)
1822 *msg = ref_msg(rec, logend);
1823 if (cutoff_time)
1824 *cutoff_time = date;
1825 if (cutoff_tz)
1826 *cutoff_tz = tz;
1827 if (cutoff_cnt)
1828 *cutoff_cnt = reccnt - 1;
1829 if (lastrec) {
1830 if (get_sha1_hex(lastrec, logged_sha1))
1831 die("Log %s is corrupt.", logfile);
1832 if (get_sha1_hex(rec + 41, sha1))
1833 die("Log %s is corrupt.", logfile);
1834 if (hashcmp(logged_sha1, sha1)) {
1835 warning("Log %s has gap after %s.",
1836 logfile, show_date(date, tz, DATE_RFC2822));
1839 else if (date == at_time) {
1840 if (get_sha1_hex(rec + 41, sha1))
1841 die("Log %s is corrupt.", logfile);
1843 else {
1844 if (get_sha1_hex(rec + 41, logged_sha1))
1845 die("Log %s is corrupt.", logfile);
1846 if (hashcmp(logged_sha1, sha1)) {
1847 warning("Log %s unexpectedly ended on %s.",
1848 logfile, show_date(date, tz, DATE_RFC2822));
1851 munmap(log_mapped, mapsz);
1852 return 0;
1854 lastrec = rec;
1855 if (cnt > 0)
1856 cnt--;
1859 rec = logdata;
1860 while (rec < logend && *rec != '>' && *rec != '\n')
1861 rec++;
1862 if (rec == logend || *rec == '\n')
1863 die("Log %s is corrupt.", logfile);
1864 date = strtoul(rec + 1, &tz_c, 10);
1865 tz = strtoul(tz_c, NULL, 10);
1866 if (get_sha1_hex(logdata, sha1))
1867 die("Log %s is corrupt.", logfile);
1868 if (is_null_sha1(sha1)) {
1869 if (get_sha1_hex(logdata + 41, sha1))
1870 die("Log %s is corrupt.", logfile);
1872 if (msg)
1873 *msg = ref_msg(logdata, logend);
1874 munmap(log_mapped, mapsz);
1876 if (cutoff_time)
1877 *cutoff_time = date;
1878 if (cutoff_tz)
1879 *cutoff_tz = tz;
1880 if (cutoff_cnt)
1881 *cutoff_cnt = reccnt;
1882 return 1;
1885 int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
1887 const char *logfile;
1888 FILE *logfp;
1889 struct strbuf sb = STRBUF_INIT;
1890 int ret = 0;
1892 logfile = git_path("logs/%s", refname);
1893 logfp = fopen(logfile, "r");
1894 if (!logfp)
1895 return -1;
1897 if (ofs) {
1898 struct stat statbuf;
1899 if (fstat(fileno(logfp), &statbuf) ||
1900 statbuf.st_size < ofs ||
1901 fseek(logfp, -ofs, SEEK_END) ||
1902 strbuf_getwholeline(&sb, logfp, '\n')) {
1903 fclose(logfp);
1904 strbuf_release(&sb);
1905 return -1;
1909 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1910 unsigned char osha1[20], nsha1[20];
1911 char *email_end, *message;
1912 unsigned long timestamp;
1913 int tz;
1915 /* old SP new SP name <email> SP time TAB msg LF */
1916 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1917 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1918 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1919 !(email_end = strchr(sb.buf + 82, '>')) ||
1920 email_end[1] != ' ' ||
1921 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1922 !message || message[0] != ' ' ||
1923 (message[1] != '+' && message[1] != '-') ||
1924 !isdigit(message[2]) || !isdigit(message[3]) ||
1925 !isdigit(message[4]) || !isdigit(message[5]))
1926 continue; /* corrupt? */
1927 email_end[1] = '\0';
1928 tz = strtol(message + 1, NULL, 10);
1929 if (message[6] != '\t')
1930 message += 6;
1931 else
1932 message += 7;
1933 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1934 cb_data);
1935 if (ret)
1936 break;
1938 fclose(logfp);
1939 strbuf_release(&sb);
1940 return ret;
1943 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
1945 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
1948 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1950 DIR *dir = opendir(git_path("logs/%s", base));
1951 int retval = 0;
1953 if (dir) {
1954 struct dirent *de;
1955 int baselen = strlen(base);
1956 char *log = xmalloc(baselen + 257);
1958 memcpy(log, base, baselen);
1959 if (baselen && base[baselen-1] != '/')
1960 log[baselen++] = '/';
1962 while ((de = readdir(dir)) != NULL) {
1963 struct stat st;
1964 int namelen;
1966 if (de->d_name[0] == '.')
1967 continue;
1968 namelen = strlen(de->d_name);
1969 if (namelen > 255)
1970 continue;
1971 if (has_extension(de->d_name, ".lock"))
1972 continue;
1973 memcpy(log + baselen, de->d_name, namelen+1);
1974 if (stat(git_path("logs/%s", log), &st) < 0)
1975 continue;
1976 if (S_ISDIR(st.st_mode)) {
1977 retval = do_for_each_reflog(log, fn, cb_data);
1978 } else {
1979 unsigned char sha1[20];
1980 if (read_ref_full(log, sha1, 0, NULL))
1981 retval = error("bad ref for %s", log);
1982 else
1983 retval = fn(log, sha1, 0, cb_data);
1985 if (retval)
1986 break;
1988 free(log);
1989 closedir(dir);
1991 else if (*base)
1992 return errno;
1993 return retval;
1996 int for_each_reflog(each_ref_fn fn, void *cb_data)
1998 return do_for_each_reflog("", fn, cb_data);
2001 int update_ref(const char *action, const char *refname,
2002 const unsigned char *sha1, const unsigned char *oldval,
2003 int flags, enum action_on_err onerr)
2005 static struct ref_lock *lock;
2006 lock = lock_any_ref_for_update(refname, oldval, flags);
2007 if (!lock) {
2008 const char *str = "Cannot lock the ref '%s'.";
2009 switch (onerr) {
2010 case MSG_ON_ERR: error(str, refname); break;
2011 case DIE_ON_ERR: die(str, refname); break;
2012 case QUIET_ON_ERR: break;
2014 return 1;
2016 if (write_ref_sha1(lock, sha1, action) < 0) {
2017 const char *str = "Cannot update the ref '%s'.";
2018 switch (onerr) {
2019 case MSG_ON_ERR: error(str, refname); break;
2020 case DIE_ON_ERR: die(str, refname); break;
2021 case QUIET_ON_ERR: break;
2023 return 1;
2025 return 0;
2028 int ref_exists(const char *refname)
2030 unsigned char sha1[20];
2031 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
2034 struct ref *find_ref_by_name(const struct ref *list, const char *name)
2036 for ( ; list; list = list->next)
2037 if (!strcmp(list->name, name))
2038 return (struct ref *)list;
2039 return NULL;
2043 * generate a format suitable for scanf from a ref_rev_parse_rules
2044 * rule, that is replace the "%.*s" spec with a "%s" spec
2046 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2048 char *spec;
2050 spec = strstr(rule, "%.*s");
2051 if (!spec || strstr(spec + 4, "%.*s"))
2052 die("invalid rule in ref_rev_parse_rules: %s", rule);
2054 /* copy all until spec */
2055 strncpy(scanf_fmt, rule, spec - rule);
2056 scanf_fmt[spec - rule] = '\0';
2057 /* copy new spec */
2058 strcat(scanf_fmt, "%s");
2059 /* copy remaining rule */
2060 strcat(scanf_fmt, spec + 4);
2062 return;
2065 char *shorten_unambiguous_ref(const char *refname, int strict)
2067 int i;
2068 static char **scanf_fmts;
2069 static int nr_rules;
2070 char *short_name;
2072 /* pre generate scanf formats from ref_rev_parse_rules[] */
2073 if (!nr_rules) {
2074 size_t total_len = 0;
2076 /* the rule list is NULL terminated, count them first */
2077 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2078 /* no +1 because strlen("%s") < strlen("%.*s") */
2079 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2081 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2083 total_len = 0;
2084 for (i = 0; i < nr_rules; i++) {
2085 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2086 + total_len;
2087 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2088 total_len += strlen(ref_rev_parse_rules[i]);
2092 /* bail out if there are no rules */
2093 if (!nr_rules)
2094 return xstrdup(refname);
2096 /* buffer for scanf result, at most refname must fit */
2097 short_name = xstrdup(refname);
2099 /* skip first rule, it will always match */
2100 for (i = nr_rules - 1; i > 0 ; --i) {
2101 int j;
2102 int rules_to_fail = i;
2103 int short_name_len;
2105 if (1 != sscanf(refname, scanf_fmts[i], short_name))
2106 continue;
2108 short_name_len = strlen(short_name);
2111 * in strict mode, all (except the matched one) rules
2112 * must fail to resolve to a valid non-ambiguous ref
2114 if (strict)
2115 rules_to_fail = nr_rules;
2118 * check if the short name resolves to a valid ref,
2119 * but use only rules prior to the matched one
2121 for (j = 0; j < rules_to_fail; j++) {
2122 const char *rule = ref_rev_parse_rules[j];
2123 char refname[PATH_MAX];
2125 /* skip matched rule */
2126 if (i == j)
2127 continue;
2130 * the short name is ambiguous, if it resolves
2131 * (with this previous rule) to a valid ref
2132 * read_ref() returns 0 on success
2134 mksnpath(refname, sizeof(refname),
2135 rule, short_name_len, short_name);
2136 if (ref_exists(refname))
2137 break;
2141 * short name is non-ambiguous if all previous rules
2142 * haven't resolved to a valid ref
2144 if (j == rules_to_fail)
2145 return short_name;
2148 free(short_name);
2149 return xstrdup(refname);