repack_without_ref(): remove temporary
[git/jrn.git] / refs.c
blob2e7bc0c5c1bd188b936b2e1ed355c17e4b38c500
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;
20 struct ref_entry **refs;
24 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
25 * Return a pointer to the refname within the line (null-terminated),
26 * or NULL if there was a problem.
28 static const char *parse_ref_line(char *line, unsigned char *sha1)
31 * 42: the answer to everything.
33 * In this case, it happens to be the answer to
34 * 40 (length of sha1 hex representation)
35 * +1 (space in between hex and name)
36 * +1 (newline at the end of the line)
38 int len = strlen(line) - 42;
40 if (len <= 0)
41 return NULL;
42 if (get_sha1_hex(line, sha1) < 0)
43 return NULL;
44 if (!isspace(line[40]))
45 return NULL;
46 line += 41;
47 if (isspace(*line))
48 return NULL;
49 if (line[len] != '\n')
50 return NULL;
51 line[len] = 0;
53 return line;
56 /* Add a ref_entry to the end of the ref_array (unsorted). */
57 static void add_ref(const char *refname, const unsigned char *sha1,
58 int flag, int check_name, struct ref_array *refs,
59 struct ref_entry **new_entry)
61 int len;
62 struct ref_entry *entry;
64 /* Allocate it and add it in.. */
65 len = strlen(refname) + 1;
66 entry = xmalloc(sizeof(struct ref_entry) + len);
67 hashcpy(entry->sha1, sha1);
68 hashclr(entry->peeled);
69 if (check_name &&
70 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
71 die("Reference has invalid format: '%s'", refname);
72 memcpy(entry->name, refname, len);
73 entry->flag = flag;
74 if (new_entry)
75 *new_entry = entry;
76 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
77 refs->refs[refs->nr++] = entry;
80 static int ref_entry_cmp(const void *a, const void *b)
82 struct ref_entry *one = *(struct ref_entry **)a;
83 struct ref_entry *two = *(struct ref_entry **)b;
84 return strcmp(one->name, two->name);
88 * Emit a warning and return true iff ref1 and ref2 have the same name
89 * and the same sha1. Die if they have the same name but different
90 * sha1s.
92 static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
94 if (!strcmp(ref1->name, ref2->name)) {
95 /* Duplicate name; make sure that the SHA1s match: */
96 if (hashcmp(ref1->sha1, ref2->sha1))
97 die("Duplicated ref, and SHA1s don't match: %s",
98 ref1->name);
99 warning("Duplicated ref: %s", ref1->name);
100 return 1;
101 } else {
102 return 0;
106 static void sort_ref_array(struct ref_array *array)
108 int i, j;
110 /* Nothing to sort unless there are at least two entries */
111 if (array->nr < 2)
112 return;
114 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
116 /* Remove any duplicates from the ref_array */
117 i = 0;
118 for (j = 1; j < array->nr; j++) {
119 if (is_dup_ref(array->refs[i], array->refs[j])) {
120 free(array->refs[j]);
121 continue;
123 array->refs[++i] = array->refs[j];
125 array->nr = i + 1;
128 static struct ref_entry *search_ref_array(struct ref_array *array, const char *refname)
130 struct ref_entry *e, **r;
131 int len;
133 if (refname == NULL)
134 return NULL;
136 if (!array->nr)
137 return NULL;
139 len = strlen(refname) + 1;
140 e = xmalloc(sizeof(struct ref_entry) + len);
141 memcpy(e->name, refname, len);
143 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
145 free(e);
147 if (r == NULL)
148 return NULL;
150 return *r;
154 * Future: need to be in "struct repository"
155 * when doing a full libification.
157 static struct ref_cache {
158 struct ref_cache *next;
159 char did_loose;
160 char did_packed;
161 struct ref_array loose;
162 struct ref_array packed;
163 /* The submodule name, or "" for the main repo. */
164 char name[FLEX_ARRAY];
165 } *ref_cache;
167 static struct ref_entry *current_ref;
169 static struct ref_array extra_refs;
171 static void clear_ref_array(struct ref_array *array)
173 int i;
174 for (i = 0; i < array->nr; i++)
175 free(array->refs[i]);
176 free(array->refs);
177 array->nr = array->alloc = 0;
178 array->refs = NULL;
181 static void clear_packed_ref_cache(struct ref_cache *refs)
183 if (refs->did_packed)
184 clear_ref_array(&refs->packed);
185 refs->did_packed = 0;
188 static void clear_loose_ref_cache(struct ref_cache *refs)
190 if (refs->did_loose)
191 clear_ref_array(&refs->loose);
192 refs->did_loose = 0;
195 static struct ref_cache *create_ref_cache(const char *submodule)
197 int len;
198 struct ref_cache *refs;
199 if (!submodule)
200 submodule = "";
201 len = strlen(submodule) + 1;
202 refs = xcalloc(1, sizeof(struct ref_cache) + len);
203 memcpy(refs->name, submodule, len);
204 return refs;
208 * Return a pointer to a ref_cache for the specified submodule. For
209 * the main repository, use submodule==NULL. The returned structure
210 * will be allocated and initialized but not necessarily populated; it
211 * should not be freed.
213 static struct ref_cache *get_ref_cache(const char *submodule)
215 struct ref_cache *refs = ref_cache;
216 if (!submodule)
217 submodule = "";
218 while (refs) {
219 if (!strcmp(submodule, refs->name))
220 return refs;
221 refs = refs->next;
224 refs = create_ref_cache(submodule);
225 refs->next = ref_cache;
226 ref_cache = refs;
227 return refs;
230 void invalidate_ref_cache(const char *submodule)
232 struct ref_cache *refs = get_ref_cache(submodule);
233 clear_packed_ref_cache(refs);
234 clear_loose_ref_cache(refs);
237 static void read_packed_refs(FILE *f, struct ref_array *array)
239 struct ref_entry *last = NULL;
240 char refline[PATH_MAX];
241 int flag = REF_ISPACKED;
243 while (fgets(refline, sizeof(refline), f)) {
244 unsigned char sha1[20];
245 const char *refname;
246 static const char header[] = "# pack-refs with:";
248 if (!strncmp(refline, header, sizeof(header)-1)) {
249 const char *traits = refline + sizeof(header) - 1;
250 if (strstr(traits, " peeled "))
251 flag |= REF_KNOWS_PEELED;
252 /* perhaps other traits later as well */
253 continue;
256 refname = parse_ref_line(refline, sha1);
257 if (refname) {
258 add_ref(refname, sha1, flag, 1, array, &last);
259 continue;
261 if (last &&
262 refline[0] == '^' &&
263 strlen(refline) == 42 &&
264 refline[41] == '\n' &&
265 !get_sha1_hex(refline + 1, sha1))
266 hashcpy(last->peeled, sha1);
268 sort_ref_array(array);
271 void add_extra_ref(const char *refname, const unsigned char *sha1, int flag)
273 add_ref(refname, sha1, flag, 0, &extra_refs, NULL);
276 void clear_extra_refs(void)
278 clear_ref_array(&extra_refs);
281 static struct ref_array *get_packed_refs(struct ref_cache *refs)
283 if (!refs->did_packed) {
284 const char *packed_refs_file;
285 FILE *f;
287 if (*refs->name)
288 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
289 else
290 packed_refs_file = git_path("packed-refs");
291 f = fopen(packed_refs_file, "r");
292 if (f) {
293 read_packed_refs(f, &refs->packed);
294 fclose(f);
296 refs->did_packed = 1;
298 return &refs->packed;
301 static void get_ref_dir(struct ref_cache *refs, const char *base,
302 struct ref_array *array)
304 DIR *dir;
305 const char *path;
307 if (*refs->name)
308 path = git_path_submodule(refs->name, "%s", base);
309 else
310 path = git_path("%s", base);
313 dir = opendir(path);
315 if (dir) {
316 struct dirent *de;
317 int baselen = strlen(base);
318 char *refname = xmalloc(baselen + 257);
320 memcpy(refname, base, baselen);
321 if (baselen && base[baselen-1] != '/')
322 refname[baselen++] = '/';
324 while ((de = readdir(dir)) != NULL) {
325 unsigned char sha1[20];
326 struct stat st;
327 int flag;
328 int namelen;
329 const char *refdir;
331 if (de->d_name[0] == '.')
332 continue;
333 namelen = strlen(de->d_name);
334 if (namelen > 255)
335 continue;
336 if (has_extension(de->d_name, ".lock"))
337 continue;
338 memcpy(refname + baselen, de->d_name, namelen+1);
339 refdir = *refs->name
340 ? git_path_submodule(refs->name, "%s", refname)
341 : git_path("%s", refname);
342 if (stat(refdir, &st) < 0)
343 continue;
344 if (S_ISDIR(st.st_mode)) {
345 get_ref_dir(refs, refname, array);
346 continue;
348 if (*refs->name) {
349 hashclr(sha1);
350 flag = 0;
351 if (resolve_gitlink_ref(refs->name, refname, sha1) < 0) {
352 hashclr(sha1);
353 flag |= REF_ISBROKEN;
355 } else if (read_ref_full(refname, sha1, 1, &flag)) {
356 hashclr(sha1);
357 flag |= REF_ISBROKEN;
359 add_ref(refname, sha1, flag, 1, array, NULL);
361 free(refname);
362 closedir(dir);
366 struct warn_if_dangling_data {
367 FILE *fp;
368 const char *refname;
369 const char *msg_fmt;
372 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
373 int flags, void *cb_data)
375 struct warn_if_dangling_data *d = cb_data;
376 const char *resolves_to;
377 unsigned char junk[20];
379 if (!(flags & REF_ISSYMREF))
380 return 0;
382 resolves_to = resolve_ref(refname, junk, 0, NULL);
383 if (!resolves_to || strcmp(resolves_to, d->refname))
384 return 0;
386 fprintf(d->fp, d->msg_fmt, refname);
387 return 0;
390 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
392 struct warn_if_dangling_data data;
394 data.fp = fp;
395 data.refname = refname;
396 data.msg_fmt = msg_fmt;
397 for_each_rawref(warn_if_dangling_symref, &data);
400 static struct ref_array *get_loose_refs(struct ref_cache *refs)
402 if (!refs->did_loose) {
403 get_ref_dir(refs, "refs", &refs->loose);
404 sort_ref_array(&refs->loose);
405 refs->did_loose = 1;
407 return &refs->loose;
410 /* We allow "recursive" symbolic refs. Only within reason, though */
411 #define MAXDEPTH 5
412 #define MAXREFLEN (1024)
415 * Called by resolve_gitlink_ref_recursive() after it failed to read
416 * from the loose refs in ref_cache refs. Find <refname> in the
417 * packed-refs file for the submodule.
419 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
420 const char *refname, unsigned char *sha1)
422 struct ref_entry *ref;
423 struct ref_array *array = get_packed_refs(refs);
425 ref = search_ref_array(array, refname);
426 if (ref == NULL)
427 return -1;
429 memcpy(sha1, ref->sha1, 20);
430 return 0;
433 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
434 const char *refname, unsigned char *sha1,
435 int recursion)
437 int fd, len;
438 char buffer[128], *p;
439 char *path;
441 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
442 return -1;
443 path = *refs->name
444 ? git_path_submodule(refs->name, "%s", refname)
445 : git_path("%s", refname);
446 fd = open(path, O_RDONLY);
447 if (fd < 0)
448 return resolve_gitlink_packed_ref(refs, refname, sha1);
450 len = read(fd, buffer, sizeof(buffer)-1);
451 close(fd);
452 if (len < 0)
453 return -1;
454 while (len && isspace(buffer[len-1]))
455 len--;
456 buffer[len] = 0;
458 /* Was it a detached head or an old-fashioned symlink? */
459 if (!get_sha1_hex(buffer, sha1))
460 return 0;
462 /* Symref? */
463 if (strncmp(buffer, "ref:", 4))
464 return -1;
465 p = buffer + 4;
466 while (isspace(*p))
467 p++;
469 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
472 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
474 int len = strlen(path), retval;
475 char *submodule;
476 struct ref_cache *refs;
478 while (len && path[len-1] == '/')
479 len--;
480 if (!len)
481 return -1;
482 submodule = xstrndup(path, len);
483 refs = get_ref_cache(submodule);
484 free(submodule);
486 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
487 return retval;
491 * Try to read ref from the packed references. On success, set sha1
492 * and return 0; otherwise, return -1.
494 static int get_packed_ref(const char *refname, unsigned char *sha1)
496 struct ref_array *packed = get_packed_refs(get_ref_cache(NULL));
497 struct ref_entry *entry = search_ref_array(packed, refname);
498 if (entry) {
499 hashcpy(sha1, entry->sha1);
500 return 0;
502 return -1;
505 const char *resolve_ref(const char *refname, unsigned char *sha1, int reading, int *flag)
507 int depth = MAXDEPTH;
508 ssize_t len;
509 char buffer[256];
510 static char refname_buffer[256];
512 if (flag)
513 *flag = 0;
515 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
516 return NULL;
518 for (;;) {
519 char path[PATH_MAX];
520 struct stat st;
521 char *buf;
522 int fd;
524 if (--depth < 0)
525 return NULL;
527 git_snpath(path, sizeof(path), "%s", refname);
529 if (lstat(path, &st) < 0) {
530 if (errno != ENOENT)
531 return NULL;
533 * The loose reference file does not exist;
534 * check for a packed reference.
536 if (!get_packed_ref(refname, sha1)) {
537 if (flag)
538 *flag |= REF_ISPACKED;
539 return refname;
541 /* The reference is not a packed reference, either. */
542 if (reading) {
543 return NULL;
544 } else {
545 hashclr(sha1);
546 return refname;
550 /* Follow "normalized" - ie "refs/.." symlinks by hand */
551 if (S_ISLNK(st.st_mode)) {
552 len = readlink(path, buffer, sizeof(buffer)-1);
553 if (len < 0)
554 return NULL;
555 buffer[len] = 0;
556 if (!prefixcmp(buffer, "refs/") &&
557 !check_refname_format(buffer, 0)) {
558 strcpy(refname_buffer, buffer);
559 refname = refname_buffer;
560 if (flag)
561 *flag |= REF_ISSYMREF;
562 continue;
566 /* Is it a directory? */
567 if (S_ISDIR(st.st_mode)) {
568 errno = EISDIR;
569 return NULL;
573 * Anything else, just open it and try to use it as
574 * a ref
576 fd = open(path, O_RDONLY);
577 if (fd < 0)
578 return NULL;
579 len = read_in_full(fd, buffer, sizeof(buffer)-1);
580 close(fd);
581 if (len < 0)
582 return NULL;
583 while (len && isspace(buffer[len-1]))
584 len--;
585 buffer[len] = '\0';
588 * Is it a symbolic ref?
590 if (prefixcmp(buffer, "ref:"))
591 break;
592 if (flag)
593 *flag |= REF_ISSYMREF;
594 buf = buffer + 4;
595 while (isspace(*buf))
596 buf++;
597 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
598 if (flag)
599 *flag |= REF_ISBROKEN;
600 return NULL;
602 refname = strcpy(refname_buffer, buf);
604 /* Please note that FETCH_HEAD has a second line containing other data. */
605 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
606 if (flag)
607 *flag |= REF_ISBROKEN;
608 return NULL;
610 return refname;
613 /* The argument to filter_refs */
614 struct ref_filter {
615 const char *pattern;
616 each_ref_fn *fn;
617 void *cb_data;
620 int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
622 if (resolve_ref(refname, sha1, reading, flags))
623 return 0;
624 return -1;
627 int read_ref(const char *refname, unsigned char *sha1)
629 return read_ref_full(refname, sha1, 1, NULL);
632 #define DO_FOR_EACH_INCLUDE_BROKEN 01
633 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
634 int flags, void *cb_data, struct ref_entry *entry)
636 if (prefixcmp(entry->name, base))
637 return 0;
639 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
640 if (entry->flag & REF_ISBROKEN)
641 return 0; /* ignore broken refs e.g. dangling symref */
642 if (!has_sha1_file(entry->sha1)) {
643 error("%s does not point to a valid object!", entry->name);
644 return 0;
647 current_ref = entry;
648 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
651 static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
652 void *data)
654 struct ref_filter *filter = (struct ref_filter *)data;
655 if (fnmatch(filter->pattern, refname, 0))
656 return 0;
657 return filter->fn(refname, sha1, flags, filter->cb_data);
660 int peel_ref(const char *refname, unsigned char *sha1)
662 int flag;
663 unsigned char base[20];
664 struct object *o;
666 if (current_ref && (current_ref->name == refname
667 || !strcmp(current_ref->name, refname))) {
668 if (current_ref->flag & REF_KNOWS_PEELED) {
669 hashcpy(sha1, current_ref->peeled);
670 return 0;
672 hashcpy(base, current_ref->sha1);
673 goto fallback;
676 if (read_ref_full(refname, base, 1, &flag))
677 return -1;
679 if ((flag & REF_ISPACKED)) {
680 struct ref_array *array = get_packed_refs(get_ref_cache(NULL));
681 struct ref_entry *r = search_ref_array(array, refname);
683 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
684 hashcpy(sha1, r->peeled);
685 return 0;
689 fallback:
690 o = parse_object(base);
691 if (o && o->type == OBJ_TAG) {
692 o = deref_tag(o, refname, 0);
693 if (o) {
694 hashcpy(sha1, o->sha1);
695 return 0;
698 return -1;
701 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
702 int trim, int flags, void *cb_data)
704 int retval = 0, i, p = 0, l = 0;
705 struct ref_cache *refs = get_ref_cache(submodule);
706 struct ref_array *packed = get_packed_refs(refs);
707 struct ref_array *loose = get_loose_refs(refs);
709 struct ref_array *extra = &extra_refs;
711 for (i = 0; i < extra->nr; i++)
712 retval = do_one_ref(base, fn, trim, flags, cb_data, extra->refs[i]);
714 while (p < packed->nr && l < loose->nr) {
715 struct ref_entry *entry;
716 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
717 if (!cmp) {
718 p++;
719 continue;
721 if (cmp > 0) {
722 entry = loose->refs[l++];
723 } else {
724 entry = packed->refs[p++];
726 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
727 if (retval)
728 goto end_each;
731 if (l < loose->nr) {
732 p = l;
733 packed = loose;
736 for (; p < packed->nr; p++) {
737 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
738 if (retval)
739 goto end_each;
742 end_each:
743 current_ref = NULL;
744 return retval;
748 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
750 unsigned char sha1[20];
751 int flag;
753 if (submodule) {
754 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
755 return fn("HEAD", sha1, 0, cb_data);
757 return 0;
760 if (!read_ref_full("HEAD", sha1, 1, &flag))
761 return fn("HEAD", sha1, flag, cb_data);
763 return 0;
766 int head_ref(each_ref_fn fn, void *cb_data)
768 return do_head_ref(NULL, fn, cb_data);
771 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
773 return do_head_ref(submodule, fn, cb_data);
776 int for_each_ref(each_ref_fn fn, void *cb_data)
778 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
781 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
783 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
786 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
788 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
791 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
792 each_ref_fn fn, void *cb_data)
794 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
797 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
799 return for_each_ref_in("refs/tags/", fn, cb_data);
802 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
804 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
807 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
809 return for_each_ref_in("refs/heads/", fn, cb_data);
812 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
814 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
817 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
819 return for_each_ref_in("refs/remotes/", fn, cb_data);
822 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
824 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
827 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
829 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
832 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
834 struct strbuf buf = STRBUF_INIT;
835 int ret = 0;
836 unsigned char sha1[20];
837 int flag;
839 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
840 if (!read_ref_full(buf.buf, sha1, 1, &flag))
841 ret = fn(buf.buf, sha1, flag, cb_data);
842 strbuf_release(&buf);
844 return ret;
847 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
849 struct strbuf buf = STRBUF_INIT;
850 int ret;
851 strbuf_addf(&buf, "%srefs/", get_git_namespace());
852 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
853 strbuf_release(&buf);
854 return ret;
857 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
858 const char *prefix, void *cb_data)
860 struct strbuf real_pattern = STRBUF_INIT;
861 struct ref_filter filter;
862 int ret;
864 if (!prefix && prefixcmp(pattern, "refs/"))
865 strbuf_addstr(&real_pattern, "refs/");
866 else if (prefix)
867 strbuf_addstr(&real_pattern, prefix);
868 strbuf_addstr(&real_pattern, pattern);
870 if (!has_glob_specials(pattern)) {
871 /* Append implied '/' '*' if not present. */
872 if (real_pattern.buf[real_pattern.len - 1] != '/')
873 strbuf_addch(&real_pattern, '/');
874 /* No need to check for '*', there is none. */
875 strbuf_addch(&real_pattern, '*');
878 filter.pattern = real_pattern.buf;
879 filter.fn = fn;
880 filter.cb_data = cb_data;
881 ret = for_each_ref(filter_refs, &filter);
883 strbuf_release(&real_pattern);
884 return ret;
887 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
889 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
892 int for_each_rawref(each_ref_fn fn, void *cb_data)
894 return do_for_each_ref(NULL, "", fn, 0,
895 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
899 * Make sure "ref" is something reasonable to have under ".git/refs/";
900 * We do not like it if:
902 * - any path component of it begins with ".", or
903 * - it has double dots "..", or
904 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
905 * - it ends with a "/".
906 * - it ends with ".lock"
907 * - it contains a "\" (backslash)
910 /* Return true iff ch is not allowed in reference names. */
911 static inline int bad_ref_char(int ch)
913 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
914 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
915 return 1;
916 /* 2.13 Pattern Matching Notation */
917 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
918 return 1;
919 return 0;
923 * Try to read one refname component from the front of refname. Return
924 * the length of the component found, or -1 if the component is not
925 * legal.
927 static int check_refname_component(const char *refname, int flags)
929 const char *cp;
930 char last = '\0';
932 for (cp = refname; ; cp++) {
933 char ch = *cp;
934 if (ch == '\0' || ch == '/')
935 break;
936 if (bad_ref_char(ch))
937 return -1; /* Illegal character in refname. */
938 if (last == '.' && ch == '.')
939 return -1; /* Refname contains "..". */
940 if (last == '@' && ch == '{')
941 return -1; /* Refname contains "@{". */
942 last = ch;
944 if (cp == refname)
945 return -1; /* Component has zero length. */
946 if (refname[0] == '.') {
947 if (!(flags & REFNAME_DOT_COMPONENT))
948 return -1; /* Component starts with '.'. */
950 * Even if leading dots are allowed, don't allow "."
951 * as a component (".." is prevented by a rule above).
953 if (refname[1] == '\0')
954 return -1; /* Component equals ".". */
956 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
957 return -1; /* Refname ends with ".lock". */
958 return cp - refname;
961 int check_refname_format(const char *refname, int flags)
963 int component_len, component_count = 0;
965 while (1) {
966 /* We are at the start of a path component. */
967 component_len = check_refname_component(refname, flags);
968 if (component_len < 0) {
969 if ((flags & REFNAME_REFSPEC_PATTERN) &&
970 refname[0] == '*' &&
971 (refname[1] == '\0' || refname[1] == '/')) {
972 /* Accept one wildcard as a full refname component. */
973 flags &= ~REFNAME_REFSPEC_PATTERN;
974 component_len = 1;
975 } else {
976 return -1;
979 component_count++;
980 if (refname[component_len] == '\0')
981 break;
982 /* Skip to next component. */
983 refname += component_len + 1;
986 if (refname[component_len - 1] == '.')
987 return -1; /* Refname ends with '.'. */
988 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
989 return -1; /* Refname has only one component. */
990 return 0;
993 const char *prettify_refname(const char *name)
995 return name + (
996 !prefixcmp(name, "refs/heads/") ? 11 :
997 !prefixcmp(name, "refs/tags/") ? 10 :
998 !prefixcmp(name, "refs/remotes/") ? 13 :
1002 const char *ref_rev_parse_rules[] = {
1003 "%.*s",
1004 "refs/%.*s",
1005 "refs/tags/%.*s",
1006 "refs/heads/%.*s",
1007 "refs/remotes/%.*s",
1008 "refs/remotes/%.*s/HEAD",
1009 NULL
1012 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1014 const char **p;
1015 const int abbrev_name_len = strlen(abbrev_name);
1017 for (p = rules; *p; p++) {
1018 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1019 return 1;
1023 return 0;
1026 static struct ref_lock *verify_lock(struct ref_lock *lock,
1027 const unsigned char *old_sha1, int mustexist)
1029 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1030 error("Can't verify ref %s", lock->ref_name);
1031 unlock_ref(lock);
1032 return NULL;
1034 if (hashcmp(lock->old_sha1, old_sha1)) {
1035 error("Ref %s is at %s but expected %s", lock->ref_name,
1036 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1037 unlock_ref(lock);
1038 return NULL;
1040 return lock;
1043 static int remove_empty_directories(const char *file)
1045 /* we want to create a file but there is a directory there;
1046 * if that is an empty directory (or a directory that contains
1047 * only empty directories), remove them.
1049 struct strbuf path;
1050 int result;
1052 strbuf_init(&path, 20);
1053 strbuf_addstr(&path, file);
1055 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1057 strbuf_release(&path);
1059 return result;
1063 * Return true iff a reference named refname could be created without
1064 * conflicting with the name of an existing reference. If oldrefname
1065 * is non-NULL, ignore potential conflicts with oldrefname (e.g.,
1066 * because oldrefname is scheduled for deletion in the same
1067 * operation).
1069 static int is_refname_available(const char *refname, const char *oldrefname,
1070 struct ref_array *array)
1072 int i, namlen = strlen(refname); /* e.g. 'foo/bar' */
1073 for (i = 0; i < array->nr; i++ ) {
1074 struct ref_entry *entry = array->refs[i];
1075 /* entry->name could be 'foo' or 'foo/bar/baz' */
1076 if (!oldrefname || strcmp(oldrefname, entry->name)) {
1077 int len = strlen(entry->name);
1078 int cmplen = (namlen < len) ? namlen : len;
1079 const char *lead = (namlen < len) ? entry->name : refname;
1080 if (!strncmp(refname, entry->name, cmplen) &&
1081 lead[cmplen] == '/') {
1082 error("'%s' exists; cannot create '%s'",
1083 entry->name, refname);
1084 return 0;
1088 return 1;
1092 * *string and *len will only be substituted, and *string returned (for
1093 * later free()ing) if the string passed in is a magic short-hand form
1094 * to name a branch.
1096 static char *substitute_branch_name(const char **string, int *len)
1098 struct strbuf buf = STRBUF_INIT;
1099 int ret = interpret_branch_name(*string, &buf);
1101 if (ret == *len) {
1102 size_t size;
1103 *string = strbuf_detach(&buf, &size);
1104 *len = size;
1105 return (char *)*string;
1108 return NULL;
1111 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1113 char *last_branch = substitute_branch_name(&str, &len);
1114 const char **p, *r;
1115 int refs_found = 0;
1117 *ref = NULL;
1118 for (p = ref_rev_parse_rules; *p; p++) {
1119 char fullref[PATH_MAX];
1120 unsigned char sha1_from_ref[20];
1121 unsigned char *this_result;
1122 int flag;
1124 this_result = refs_found ? sha1_from_ref : sha1;
1125 mksnpath(fullref, sizeof(fullref), *p, len, str);
1126 r = resolve_ref(fullref, this_result, 1, &flag);
1127 if (r) {
1128 if (!refs_found++)
1129 *ref = xstrdup(r);
1130 if (!warn_ambiguous_refs)
1131 break;
1132 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1133 warning("ignoring dangling symref %s.", fullref);
1134 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1135 warning("ignoring broken ref %s.", fullref);
1138 free(last_branch);
1139 return refs_found;
1142 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1144 char *last_branch = substitute_branch_name(&str, &len);
1145 const char **p;
1146 int logs_found = 0;
1148 *log = NULL;
1149 for (p = ref_rev_parse_rules; *p; p++) {
1150 struct stat st;
1151 unsigned char hash[20];
1152 char path[PATH_MAX];
1153 const char *ref, *it;
1155 mksnpath(path, sizeof(path), *p, len, str);
1156 ref = resolve_ref(path, hash, 1, NULL);
1157 if (!ref)
1158 continue;
1159 if (!stat(git_path("logs/%s", path), &st) &&
1160 S_ISREG(st.st_mode))
1161 it = path;
1162 else if (strcmp(ref, path) &&
1163 !stat(git_path("logs/%s", ref), &st) &&
1164 S_ISREG(st.st_mode))
1165 it = ref;
1166 else
1167 continue;
1168 if (!logs_found++) {
1169 *log = xstrdup(it);
1170 hashcpy(sha1, hash);
1172 if (!warn_ambiguous_refs)
1173 break;
1175 free(last_branch);
1176 return logs_found;
1179 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1180 const unsigned char *old_sha1,
1181 int flags, int *type_p)
1183 char *ref_file;
1184 const char *orig_refname = refname;
1185 struct ref_lock *lock;
1186 int last_errno = 0;
1187 int type, lflags;
1188 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1189 int missing = 0;
1191 lock = xcalloc(1, sizeof(struct ref_lock));
1192 lock->lock_fd = -1;
1194 refname = resolve_ref(refname, lock->old_sha1, mustexist, &type);
1195 if (!refname && errno == EISDIR) {
1196 /* we are trying to lock foo but we used to
1197 * have foo/bar which now does not exist;
1198 * it is normal for the empty directory 'foo'
1199 * to remain.
1201 ref_file = git_path("%s", orig_refname);
1202 if (remove_empty_directories(ref_file)) {
1203 last_errno = errno;
1204 error("there are still refs under '%s'", orig_refname);
1205 goto error_return;
1207 refname = resolve_ref(orig_refname, lock->old_sha1, mustexist, &type);
1209 if (type_p)
1210 *type_p = type;
1211 if (!refname) {
1212 last_errno = errno;
1213 error("unable to resolve reference %s: %s",
1214 orig_refname, strerror(errno));
1215 goto error_return;
1217 missing = is_null_sha1(lock->old_sha1);
1218 /* When the ref did not exist and we are creating it,
1219 * make sure there is no existing ref that is packed
1220 * whose name begins with our refname, nor a ref whose
1221 * name is a proper prefix of our refname.
1223 if (missing &&
1224 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
1225 last_errno = ENOTDIR;
1226 goto error_return;
1229 lock->lk = xcalloc(1, sizeof(struct lock_file));
1231 lflags = LOCK_DIE_ON_ERROR;
1232 if (flags & REF_NODEREF) {
1233 refname = orig_refname;
1234 lflags |= LOCK_NODEREF;
1236 lock->ref_name = xstrdup(refname);
1237 lock->orig_ref_name = xstrdup(orig_refname);
1238 ref_file = git_path("%s", refname);
1239 if (missing)
1240 lock->force_write = 1;
1241 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1242 lock->force_write = 1;
1244 if (safe_create_leading_directories(ref_file)) {
1245 last_errno = errno;
1246 error("unable to create directory for %s", ref_file);
1247 goto error_return;
1250 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1251 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1253 error_return:
1254 unlock_ref(lock);
1255 errno = last_errno;
1256 return NULL;
1259 struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
1261 char refpath[PATH_MAX];
1262 if (check_refname_format(refname, 0))
1263 return NULL;
1264 strcpy(refpath, mkpath("refs/%s", refname));
1265 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1268 struct ref_lock *lock_any_ref_for_update(const char *refname,
1269 const unsigned char *old_sha1, int flags)
1271 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1272 return NULL;
1273 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
1276 static struct lock_file packlock;
1278 static int repack_without_ref(const char *refname)
1280 struct ref_array *packed;
1281 int fd, i;
1283 packed = get_packed_refs(get_ref_cache(NULL));
1284 if (search_ref_array(packed, refname) == NULL)
1285 return 0;
1286 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1287 if (fd < 0) {
1288 unable_to_lock_error(git_path("packed-refs"), errno);
1289 return error("cannot delete '%s' from packed refs", refname);
1292 for (i = 0; i < packed->nr; i++) {
1293 char line[PATH_MAX + 100];
1294 int len;
1295 struct ref_entry *ref = packed->refs[i];
1297 if (!strcmp(refname, ref->name))
1298 continue;
1299 len = snprintf(line, sizeof(line), "%s %s\n",
1300 sha1_to_hex(ref->sha1), ref->name);
1301 /* this should not happen but just being defensive */
1302 if (len > sizeof(line))
1303 die("too long a refname '%s'", ref->name);
1304 write_or_die(fd, line, len);
1306 return commit_lock_file(&packlock);
1309 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1311 struct ref_lock *lock;
1312 int err, i = 0, ret = 0, flag = 0;
1314 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1315 if (!lock)
1316 return 1;
1317 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1318 /* loose */
1319 const char *path;
1321 if (!(delopt & REF_NODEREF)) {
1322 i = strlen(lock->lk->filename) - 5; /* .lock */
1323 lock->lk->filename[i] = 0;
1324 path = lock->lk->filename;
1325 } else {
1326 path = git_path("%s", refname);
1328 err = unlink_or_warn(path);
1329 if (err && errno != ENOENT)
1330 ret = 1;
1332 if (!(delopt & REF_NODEREF))
1333 lock->lk->filename[i] = '.';
1335 /* removing the loose one could have resurrected an earlier
1336 * packed one. Also, if it was not loose we need to repack
1337 * without it.
1339 ret |= repack_without_ref(refname);
1341 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1342 invalidate_ref_cache(NULL);
1343 unlock_ref(lock);
1344 return ret;
1348 * People using contrib's git-new-workdir have .git/logs/refs ->
1349 * /some/other/path/.git/logs/refs, and that may live on another device.
1351 * IOW, to avoid cross device rename errors, the temporary renamed log must
1352 * live into logs/refs.
1354 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1356 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
1358 unsigned char sha1[20], orig_sha1[20];
1359 int flag = 0, logmoved = 0;
1360 struct ref_lock *lock;
1361 struct stat loginfo;
1362 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
1363 const char *symref = NULL;
1364 struct ref_cache *refs = get_ref_cache(NULL);
1366 if (log && S_ISLNK(loginfo.st_mode))
1367 return error("reflog for %s is a symlink", oldrefname);
1369 symref = resolve_ref(oldrefname, orig_sha1, 1, &flag);
1370 if (flag & REF_ISSYMREF)
1371 return error("refname %s is a symbolic ref, renaming it is not supported",
1372 oldrefname);
1373 if (!symref)
1374 return error("refname %s not found", oldrefname);
1376 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
1377 return 1;
1379 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
1380 return 1;
1382 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
1383 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1384 oldrefname, strerror(errno));
1386 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1387 error("unable to delete old %s", oldrefname);
1388 goto rollback;
1391 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1392 delete_ref(newrefname, sha1, REF_NODEREF)) {
1393 if (errno==EISDIR) {
1394 if (remove_empty_directories(git_path("%s", newrefname))) {
1395 error("Directory not empty: %s", newrefname);
1396 goto rollback;
1398 } else {
1399 error("unable to delete existing %s", newrefname);
1400 goto rollback;
1404 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1405 error("unable to create directory for %s", newrefname);
1406 goto rollback;
1409 retry:
1410 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
1411 if (errno==EISDIR || errno==ENOTDIR) {
1413 * rename(a, b) when b is an existing
1414 * directory ought to result in ISDIR, but
1415 * Solaris 5.8 gives ENOTDIR. Sheesh.
1417 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1418 error("Directory not empty: logs/%s", newrefname);
1419 goto rollback;
1421 goto retry;
1422 } else {
1423 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1424 newrefname, strerror(errno));
1425 goto rollback;
1428 logmoved = log;
1430 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
1431 if (!lock) {
1432 error("unable to lock %s for update", newrefname);
1433 goto rollback;
1435 lock->force_write = 1;
1436 hashcpy(lock->old_sha1, orig_sha1);
1437 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1438 error("unable to write current sha1 into %s", newrefname);
1439 goto rollback;
1442 return 0;
1444 rollback:
1445 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
1446 if (!lock) {
1447 error("unable to lock %s for rollback", oldrefname);
1448 goto rollbacklog;
1451 lock->force_write = 1;
1452 flag = log_all_ref_updates;
1453 log_all_ref_updates = 0;
1454 if (write_ref_sha1(lock, orig_sha1, NULL))
1455 error("unable to write current sha1 into %s", oldrefname);
1456 log_all_ref_updates = flag;
1458 rollbacklog:
1459 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
1460 error("unable to restore logfile %s from %s: %s",
1461 oldrefname, newrefname, strerror(errno));
1462 if (!logmoved && log &&
1463 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
1464 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1465 oldrefname, strerror(errno));
1467 return 1;
1470 int close_ref(struct ref_lock *lock)
1472 if (close_lock_file(lock->lk))
1473 return -1;
1474 lock->lock_fd = -1;
1475 return 0;
1478 int commit_ref(struct ref_lock *lock)
1480 if (commit_lock_file(lock->lk))
1481 return -1;
1482 lock->lock_fd = -1;
1483 return 0;
1486 void unlock_ref(struct ref_lock *lock)
1488 /* Do not free lock->lk -- atexit() still looks at them */
1489 if (lock->lk)
1490 rollback_lock_file(lock->lk);
1491 free(lock->ref_name);
1492 free(lock->orig_ref_name);
1493 free(lock);
1497 * copy the reflog message msg to buf, which has been allocated sufficiently
1498 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1499 * because reflog file is one line per entry.
1501 static int copy_msg(char *buf, const char *msg)
1503 char *cp = buf;
1504 char c;
1505 int wasspace = 1;
1507 *cp++ = '\t';
1508 while ((c = *msg++)) {
1509 if (wasspace && isspace(c))
1510 continue;
1511 wasspace = isspace(c);
1512 if (wasspace)
1513 c = ' ';
1514 *cp++ = c;
1516 while (buf < cp && isspace(cp[-1]))
1517 cp--;
1518 *cp++ = '\n';
1519 return cp - buf;
1522 int log_ref_setup(const char *refname, char *logfile, int bufsize)
1524 int logfd, oflags = O_APPEND | O_WRONLY;
1526 git_snpath(logfile, bufsize, "logs/%s", refname);
1527 if (log_all_ref_updates &&
1528 (!prefixcmp(refname, "refs/heads/") ||
1529 !prefixcmp(refname, "refs/remotes/") ||
1530 !prefixcmp(refname, "refs/notes/") ||
1531 !strcmp(refname, "HEAD"))) {
1532 if (safe_create_leading_directories(logfile) < 0)
1533 return error("unable to create directory for %s",
1534 logfile);
1535 oflags |= O_CREAT;
1538 logfd = open(logfile, oflags, 0666);
1539 if (logfd < 0) {
1540 if (!(oflags & O_CREAT) && errno == ENOENT)
1541 return 0;
1543 if ((oflags & O_CREAT) && errno == EISDIR) {
1544 if (remove_empty_directories(logfile)) {
1545 return error("There are still logs under '%s'",
1546 logfile);
1548 logfd = open(logfile, oflags, 0666);
1551 if (logfd < 0)
1552 return error("Unable to append to %s: %s",
1553 logfile, strerror(errno));
1556 adjust_shared_perm(logfile);
1557 close(logfd);
1558 return 0;
1561 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
1562 const unsigned char *new_sha1, const char *msg)
1564 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1565 unsigned maxlen, len;
1566 int msglen;
1567 char log_file[PATH_MAX];
1568 char *logrec;
1569 const char *committer;
1571 if (log_all_ref_updates < 0)
1572 log_all_ref_updates = !is_bare_repository();
1574 result = log_ref_setup(refname, log_file, sizeof(log_file));
1575 if (result)
1576 return result;
1578 logfd = open(log_file, oflags);
1579 if (logfd < 0)
1580 return 0;
1581 msglen = msg ? strlen(msg) : 0;
1582 committer = git_committer_info(0);
1583 maxlen = strlen(committer) + msglen + 100;
1584 logrec = xmalloc(maxlen);
1585 len = sprintf(logrec, "%s %s %s\n",
1586 sha1_to_hex(old_sha1),
1587 sha1_to_hex(new_sha1),
1588 committer);
1589 if (msglen)
1590 len += copy_msg(logrec + len - 1, msg) - 1;
1591 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1592 free(logrec);
1593 if (close(logfd) != 0 || written != len)
1594 return error("Unable to append to %s", log_file);
1595 return 0;
1598 static int is_branch(const char *refname)
1600 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1603 int write_ref_sha1(struct ref_lock *lock,
1604 const unsigned char *sha1, const char *logmsg)
1606 static char term = '\n';
1607 struct object *o;
1609 if (!lock)
1610 return -1;
1611 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1612 unlock_ref(lock);
1613 return 0;
1615 o = parse_object(sha1);
1616 if (!o) {
1617 error("Trying to write ref %s with nonexistent object %s",
1618 lock->ref_name, sha1_to_hex(sha1));
1619 unlock_ref(lock);
1620 return -1;
1622 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1623 error("Trying to write non-commit object %s to branch %s",
1624 sha1_to_hex(sha1), lock->ref_name);
1625 unlock_ref(lock);
1626 return -1;
1628 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1629 write_in_full(lock->lock_fd, &term, 1) != 1
1630 || close_ref(lock) < 0) {
1631 error("Couldn't write %s", lock->lk->filename);
1632 unlock_ref(lock);
1633 return -1;
1635 clear_loose_ref_cache(get_ref_cache(NULL));
1636 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1637 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1638 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1639 unlock_ref(lock);
1640 return -1;
1642 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1644 * Special hack: If a branch is updated directly and HEAD
1645 * points to it (may happen on the remote side of a push
1646 * for example) then logically the HEAD reflog should be
1647 * updated too.
1648 * A generic solution implies reverse symref information,
1649 * but finding all symrefs pointing to the given branch
1650 * would be rather costly for this rare event (the direct
1651 * update of a branch) to be worth it. So let's cheat and
1652 * check with HEAD only which should cover 99% of all usage
1653 * scenarios (even 100% of the default ones).
1655 unsigned char head_sha1[20];
1656 int head_flag;
1657 const char *head_ref;
1658 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1659 if (head_ref && (head_flag & REF_ISSYMREF) &&
1660 !strcmp(head_ref, lock->ref_name))
1661 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1663 if (commit_ref(lock)) {
1664 error("Couldn't set %s", lock->ref_name);
1665 unlock_ref(lock);
1666 return -1;
1668 unlock_ref(lock);
1669 return 0;
1672 int create_symref(const char *ref_target, const char *refs_heads_master,
1673 const char *logmsg)
1675 const char *lockpath;
1676 char ref[1000];
1677 int fd, len, written;
1678 char *git_HEAD = git_pathdup("%s", ref_target);
1679 unsigned char old_sha1[20], new_sha1[20];
1681 if (logmsg && read_ref(ref_target, old_sha1))
1682 hashclr(old_sha1);
1684 if (safe_create_leading_directories(git_HEAD) < 0)
1685 return error("unable to create directory for %s", git_HEAD);
1687 #ifndef NO_SYMLINK_HEAD
1688 if (prefer_symlink_refs) {
1689 unlink(git_HEAD);
1690 if (!symlink(refs_heads_master, git_HEAD))
1691 goto done;
1692 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1694 #endif
1696 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1697 if (sizeof(ref) <= len) {
1698 error("refname too long: %s", refs_heads_master);
1699 goto error_free_return;
1701 lockpath = mkpath("%s.lock", git_HEAD);
1702 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1703 if (fd < 0) {
1704 error("Unable to open %s for writing", lockpath);
1705 goto error_free_return;
1707 written = write_in_full(fd, ref, len);
1708 if (close(fd) != 0 || written != len) {
1709 error("Unable to write to %s", lockpath);
1710 goto error_unlink_return;
1712 if (rename(lockpath, git_HEAD) < 0) {
1713 error("Unable to create %s", git_HEAD);
1714 goto error_unlink_return;
1716 if (adjust_shared_perm(git_HEAD)) {
1717 error("Unable to fix permissions on %s", lockpath);
1718 error_unlink_return:
1719 unlink_or_warn(lockpath);
1720 error_free_return:
1721 free(git_HEAD);
1722 return -1;
1725 #ifndef NO_SYMLINK_HEAD
1726 done:
1727 #endif
1728 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1729 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1731 free(git_HEAD);
1732 return 0;
1735 static char *ref_msg(const char *line, const char *endp)
1737 const char *ep;
1738 line += 82;
1739 ep = memchr(line, '\n', endp - line);
1740 if (!ep)
1741 ep = endp;
1742 return xmemdupz(line, ep - line);
1745 int read_ref_at(const char *refname, unsigned long at_time, int cnt,
1746 unsigned char *sha1, char **msg,
1747 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1749 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1750 char *tz_c;
1751 int logfd, tz, reccnt = 0;
1752 struct stat st;
1753 unsigned long date;
1754 unsigned char logged_sha1[20];
1755 void *log_mapped;
1756 size_t mapsz;
1758 logfile = git_path("logs/%s", refname);
1759 logfd = open(logfile, O_RDONLY, 0);
1760 if (logfd < 0)
1761 die_errno("Unable to read log '%s'", logfile);
1762 fstat(logfd, &st);
1763 if (!st.st_size)
1764 die("Log %s is empty.", logfile);
1765 mapsz = xsize_t(st.st_size);
1766 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1767 logdata = log_mapped;
1768 close(logfd);
1770 lastrec = NULL;
1771 rec = logend = logdata + st.st_size;
1772 while (logdata < rec) {
1773 reccnt++;
1774 if (logdata < rec && *(rec-1) == '\n')
1775 rec--;
1776 lastgt = NULL;
1777 while (logdata < rec && *(rec-1) != '\n') {
1778 rec--;
1779 if (*rec == '>')
1780 lastgt = rec;
1782 if (!lastgt)
1783 die("Log %s is corrupt.", logfile);
1784 date = strtoul(lastgt + 1, &tz_c, 10);
1785 if (date <= at_time || cnt == 0) {
1786 tz = strtoul(tz_c, NULL, 10);
1787 if (msg)
1788 *msg = ref_msg(rec, logend);
1789 if (cutoff_time)
1790 *cutoff_time = date;
1791 if (cutoff_tz)
1792 *cutoff_tz = tz;
1793 if (cutoff_cnt)
1794 *cutoff_cnt = reccnt - 1;
1795 if (lastrec) {
1796 if (get_sha1_hex(lastrec, logged_sha1))
1797 die("Log %s is corrupt.", logfile);
1798 if (get_sha1_hex(rec + 41, sha1))
1799 die("Log %s is corrupt.", logfile);
1800 if (hashcmp(logged_sha1, sha1)) {
1801 warning("Log %s has gap after %s.",
1802 logfile, show_date(date, tz, DATE_RFC2822));
1805 else if (date == at_time) {
1806 if (get_sha1_hex(rec + 41, sha1))
1807 die("Log %s is corrupt.", logfile);
1809 else {
1810 if (get_sha1_hex(rec + 41, logged_sha1))
1811 die("Log %s is corrupt.", logfile);
1812 if (hashcmp(logged_sha1, sha1)) {
1813 warning("Log %s unexpectedly ended on %s.",
1814 logfile, show_date(date, tz, DATE_RFC2822));
1817 munmap(log_mapped, mapsz);
1818 return 0;
1820 lastrec = rec;
1821 if (cnt > 0)
1822 cnt--;
1825 rec = logdata;
1826 while (rec < logend && *rec != '>' && *rec != '\n')
1827 rec++;
1828 if (rec == logend || *rec == '\n')
1829 die("Log %s is corrupt.", logfile);
1830 date = strtoul(rec + 1, &tz_c, 10);
1831 tz = strtoul(tz_c, NULL, 10);
1832 if (get_sha1_hex(logdata, sha1))
1833 die("Log %s is corrupt.", logfile);
1834 if (is_null_sha1(sha1)) {
1835 if (get_sha1_hex(logdata + 41, sha1))
1836 die("Log %s is corrupt.", logfile);
1838 if (msg)
1839 *msg = ref_msg(logdata, logend);
1840 munmap(log_mapped, mapsz);
1842 if (cutoff_time)
1843 *cutoff_time = date;
1844 if (cutoff_tz)
1845 *cutoff_tz = tz;
1846 if (cutoff_cnt)
1847 *cutoff_cnt = reccnt;
1848 return 1;
1851 int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
1853 const char *logfile;
1854 FILE *logfp;
1855 struct strbuf sb = STRBUF_INIT;
1856 int ret = 0;
1858 logfile = git_path("logs/%s", refname);
1859 logfp = fopen(logfile, "r");
1860 if (!logfp)
1861 return -1;
1863 if (ofs) {
1864 struct stat statbuf;
1865 if (fstat(fileno(logfp), &statbuf) ||
1866 statbuf.st_size < ofs ||
1867 fseek(logfp, -ofs, SEEK_END) ||
1868 strbuf_getwholeline(&sb, logfp, '\n')) {
1869 fclose(logfp);
1870 strbuf_release(&sb);
1871 return -1;
1875 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1876 unsigned char osha1[20], nsha1[20];
1877 char *email_end, *message;
1878 unsigned long timestamp;
1879 int tz;
1881 /* old SP new SP name <email> SP time TAB msg LF */
1882 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1883 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1884 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1885 !(email_end = strchr(sb.buf + 82, '>')) ||
1886 email_end[1] != ' ' ||
1887 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1888 !message || message[0] != ' ' ||
1889 (message[1] != '+' && message[1] != '-') ||
1890 !isdigit(message[2]) || !isdigit(message[3]) ||
1891 !isdigit(message[4]) || !isdigit(message[5]))
1892 continue; /* corrupt? */
1893 email_end[1] = '\0';
1894 tz = strtol(message + 1, NULL, 10);
1895 if (message[6] != '\t')
1896 message += 6;
1897 else
1898 message += 7;
1899 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1900 cb_data);
1901 if (ret)
1902 break;
1904 fclose(logfp);
1905 strbuf_release(&sb);
1906 return ret;
1909 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
1911 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
1914 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1916 DIR *dir = opendir(git_path("logs/%s", base));
1917 int retval = 0;
1919 if (dir) {
1920 struct dirent *de;
1921 int baselen = strlen(base);
1922 char *log = xmalloc(baselen + 257);
1924 memcpy(log, base, baselen);
1925 if (baselen && base[baselen-1] != '/')
1926 log[baselen++] = '/';
1928 while ((de = readdir(dir)) != NULL) {
1929 struct stat st;
1930 int namelen;
1932 if (de->d_name[0] == '.')
1933 continue;
1934 namelen = strlen(de->d_name);
1935 if (namelen > 255)
1936 continue;
1937 if (has_extension(de->d_name, ".lock"))
1938 continue;
1939 memcpy(log + baselen, de->d_name, namelen+1);
1940 if (stat(git_path("logs/%s", log), &st) < 0)
1941 continue;
1942 if (S_ISDIR(st.st_mode)) {
1943 retval = do_for_each_reflog(log, fn, cb_data);
1944 } else {
1945 unsigned char sha1[20];
1946 if (read_ref_full(log, sha1, 0, NULL))
1947 retval = error("bad ref for %s", log);
1948 else
1949 retval = fn(log, sha1, 0, cb_data);
1951 if (retval)
1952 break;
1954 free(log);
1955 closedir(dir);
1957 else if (*base)
1958 return errno;
1959 return retval;
1962 int for_each_reflog(each_ref_fn fn, void *cb_data)
1964 return do_for_each_reflog("", fn, cb_data);
1967 int update_ref(const char *action, const char *refname,
1968 const unsigned char *sha1, const unsigned char *oldval,
1969 int flags, enum action_on_err onerr)
1971 static struct ref_lock *lock;
1972 lock = lock_any_ref_for_update(refname, oldval, flags);
1973 if (!lock) {
1974 const char *str = "Cannot lock the ref '%s'.";
1975 switch (onerr) {
1976 case MSG_ON_ERR: error(str, refname); break;
1977 case DIE_ON_ERR: die(str, refname); break;
1978 case QUIET_ON_ERR: break;
1980 return 1;
1982 if (write_ref_sha1(lock, sha1, action) < 0) {
1983 const char *str = "Cannot update the ref '%s'.";
1984 switch (onerr) {
1985 case MSG_ON_ERR: error(str, refname); break;
1986 case DIE_ON_ERR: die(str, refname); break;
1987 case QUIET_ON_ERR: break;
1989 return 1;
1991 return 0;
1994 int ref_exists(const char *refname)
1996 unsigned char sha1[20];
1997 return !!resolve_ref(refname, sha1, 1, NULL);
2000 struct ref *find_ref_by_name(const struct ref *list, const char *name)
2002 for ( ; list; list = list->next)
2003 if (!strcmp(list->name, name))
2004 return (struct ref *)list;
2005 return NULL;
2009 * generate a format suitable for scanf from a ref_rev_parse_rules
2010 * rule, that is replace the "%.*s" spec with a "%s" spec
2012 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2014 char *spec;
2016 spec = strstr(rule, "%.*s");
2017 if (!spec || strstr(spec + 4, "%.*s"))
2018 die("invalid rule in ref_rev_parse_rules: %s", rule);
2020 /* copy all until spec */
2021 strncpy(scanf_fmt, rule, spec - rule);
2022 scanf_fmt[spec - rule] = '\0';
2023 /* copy new spec */
2024 strcat(scanf_fmt, "%s");
2025 /* copy remaining rule */
2026 strcat(scanf_fmt, spec + 4);
2028 return;
2031 char *shorten_unambiguous_ref(const char *refname, int strict)
2033 int i;
2034 static char **scanf_fmts;
2035 static int nr_rules;
2036 char *short_name;
2038 /* pre generate scanf formats from ref_rev_parse_rules[] */
2039 if (!nr_rules) {
2040 size_t total_len = 0;
2042 /* the rule list is NULL terminated, count them first */
2043 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2044 /* no +1 because strlen("%s") < strlen("%.*s") */
2045 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2047 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2049 total_len = 0;
2050 for (i = 0; i < nr_rules; i++) {
2051 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2052 + total_len;
2053 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2054 total_len += strlen(ref_rev_parse_rules[i]);
2058 /* bail out if there are no rules */
2059 if (!nr_rules)
2060 return xstrdup(refname);
2062 /* buffer for scanf result, at most refname must fit */
2063 short_name = xstrdup(refname);
2065 /* skip first rule, it will always match */
2066 for (i = nr_rules - 1; i > 0 ; --i) {
2067 int j;
2068 int rules_to_fail = i;
2069 int short_name_len;
2071 if (1 != sscanf(refname, scanf_fmts[i], short_name))
2072 continue;
2074 short_name_len = strlen(short_name);
2077 * in strict mode, all (except the matched one) rules
2078 * must fail to resolve to a valid non-ambiguous ref
2080 if (strict)
2081 rules_to_fail = nr_rules;
2084 * check if the short name resolves to a valid ref,
2085 * but use only rules prior to the matched one
2087 for (j = 0; j < rules_to_fail; j++) {
2088 const char *rule = ref_rev_parse_rules[j];
2089 char refname[PATH_MAX];
2091 /* skip matched rule */
2092 if (i == j)
2093 continue;
2096 * the short name is ambiguous, if it resolves
2097 * (with this previous rule) to a valid ref
2098 * read_ref() returns 0 on success
2100 mksnpath(refname, sizeof(refname),
2101 rule, short_name_len, short_name);
2102 if (ref_exists(refname))
2103 break;
2107 * short name is non-ambiguous if all previous rules
2108 * haven't resolved to a valid ref
2110 if (j == rules_to_fail)
2111 return short_name;
2114 free(short_name);
2115 return xstrdup(refname);