Revert "MinGW: Add missing file mode bit defines"
[git/dscho.git] / refs.c
blob2aaa109234656f4c8d4e3f344b5f70834dffb0ae
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 if (check_refname_format(line, REFNAME_ALLOW_ONELEVEL))
54 return NULL;
56 return line;
59 static struct ref_entry *create_ref_entry(const char *refname,
60 const unsigned char *sha1, int flag)
62 int len;
63 struct ref_entry *ref;
65 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
66 die("Reference has invalid format: '%s'", refname);
67 len = strlen(refname) + 1;
68 ref = xmalloc(sizeof(struct ref_entry) + len);
69 hashcpy(ref->sha1, sha1);
70 hashclr(ref->peeled);
71 memcpy(ref->name, refname, len);
72 ref->flag = flag;
73 return ref;
76 /* Add a ref_entry to the end of the ref_array (unsorted). */
77 static void add_ref(struct ref_array *refs, struct ref_entry *ref)
79 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
80 refs->refs[refs->nr++] = ref;
83 static int ref_entry_cmp(const void *a, const void *b)
85 struct ref_entry *one = *(struct ref_entry **)a;
86 struct ref_entry *two = *(struct ref_entry **)b;
87 return strcmp(one->name, two->name);
91 * Emit a warning and return true iff ref1 and ref2 have the same name
92 * and the same sha1. Die if they have the same name but different
93 * sha1s.
95 static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
97 if (!strcmp(ref1->name, ref2->name)) {
98 /* Duplicate name; make sure that the SHA1s match: */
99 if (hashcmp(ref1->sha1, ref2->sha1))
100 die("Duplicated ref, and SHA1s don't match: %s",
101 ref1->name);
102 warning("Duplicated ref: %s", ref1->name);
103 return 1;
104 } else {
105 return 0;
109 static void sort_ref_array(struct ref_array *array)
111 int i = 0, j = 1;
113 /* Nothing to sort unless there are at least two entries */
114 if (array->nr < 2)
115 return;
117 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
119 /* Remove any duplicates from the ref_array */
120 for (; j < array->nr; j++) {
121 struct ref_entry *a = array->refs[i];
122 struct ref_entry *b = array->refs[j];
123 if (is_dup_ref(a, b)) {
124 free(b);
125 continue;
127 i++;
128 array->refs[i] = array->refs[j];
130 array->nr = i + 1;
133 static struct ref_entry *search_ref_array(struct ref_array *array, const char *refname)
135 struct ref_entry *e, **r;
136 int len;
138 if (refname == NULL)
139 return NULL;
141 if (!array->nr)
142 return NULL;
144 len = strlen(refname) + 1;
145 e = xmalloc(sizeof(struct ref_entry) + len);
146 memcpy(e->name, refname, len);
148 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
150 free(e);
152 if (r == NULL)
153 return NULL;
155 return *r;
159 * Future: need to be in "struct repository"
160 * when doing a full libification.
162 static struct ref_cache {
163 struct ref_cache *next;
164 char did_loose;
165 char did_packed;
166 struct ref_array loose;
167 struct ref_array packed;
168 /* The submodule name, or "" for the main repo. */
169 char name[FLEX_ARRAY];
170 } *ref_cache;
172 static struct ref_entry *current_ref;
174 static struct ref_array extra_refs;
176 static void clear_ref_array(struct ref_array *array)
178 int i;
179 for (i = 0; i < array->nr; i++)
180 free(array->refs[i]);
181 free(array->refs);
182 array->nr = array->alloc = 0;
183 array->refs = NULL;
186 static void clear_packed_ref_cache(struct ref_cache *refs)
188 if (refs->did_packed)
189 clear_ref_array(&refs->packed);
190 refs->did_packed = 0;
193 static void clear_loose_ref_cache(struct ref_cache *refs)
195 if (refs->did_loose)
196 clear_ref_array(&refs->loose);
197 refs->did_loose = 0;
200 static struct ref_cache *create_ref_cache(const char *submodule)
202 int len;
203 struct ref_cache *refs;
204 if (!submodule)
205 submodule = "";
206 len = strlen(submodule) + 1;
207 refs = xcalloc(1, sizeof(struct ref_cache) + len);
208 memcpy(refs->name, submodule, len);
209 return refs;
213 * Return a pointer to a ref_cache for the specified submodule. For
214 * the main repository, use submodule==NULL. The returned structure
215 * will be allocated and initialized but not necessarily populated; it
216 * should not be freed.
218 static struct ref_cache *get_ref_cache(const char *submodule)
220 struct ref_cache *refs = ref_cache;
221 if (!submodule)
222 submodule = "";
223 while (refs) {
224 if (!strcmp(submodule, refs->name))
225 return refs;
226 refs = refs->next;
229 refs = create_ref_cache(submodule);
230 refs->next = ref_cache;
231 ref_cache = refs;
232 return refs;
235 void invalidate_ref_cache(const char *submodule)
237 struct ref_cache *refs = get_ref_cache(submodule);
238 clear_packed_ref_cache(refs);
239 clear_loose_ref_cache(refs);
242 static void read_packed_refs(FILE *f, struct ref_array *array)
244 struct ref_entry *last = NULL;
245 char refline[PATH_MAX];
246 int flag = REF_ISPACKED;
248 while (fgets(refline, sizeof(refline), f)) {
249 unsigned char sha1[20];
250 const char *refname;
251 static const char header[] = "# pack-refs with:";
253 if (!strncmp(refline, header, sizeof(header)-1)) {
254 const char *traits = refline + sizeof(header) - 1;
255 if (strstr(traits, " peeled "))
256 flag |= REF_KNOWS_PEELED;
257 /* perhaps other traits later as well */
258 continue;
261 refname = parse_ref_line(refline, sha1);
262 if (refname) {
263 last = create_ref_entry(refname, sha1, flag);
264 add_ref(array, last);
265 continue;
267 if (last &&
268 refline[0] == '^' &&
269 strlen(refline) == 42 &&
270 refline[41] == '\n' &&
271 !get_sha1_hex(refline + 1, sha1))
272 hashcpy(last->peeled, sha1);
274 sort_ref_array(array);
277 void add_extra_ref(const char *refname, const unsigned char *sha1, int flag)
279 add_ref(&extra_refs, create_ref_entry(refname, sha1, flag));
282 void clear_extra_refs(void)
284 clear_ref_array(&extra_refs);
287 static struct ref_array *get_packed_refs(struct ref_cache *refs)
289 if (!refs->did_packed) {
290 const char *packed_refs_file;
291 FILE *f;
293 if (*refs->name)
294 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
295 else
296 packed_refs_file = git_path("packed-refs");
297 f = fopen(packed_refs_file, "r");
298 if (f) {
299 read_packed_refs(f, &refs->packed);
300 fclose(f);
302 refs->did_packed = 1;
304 return &refs->packed;
307 static void get_ref_dir(struct ref_cache *refs, const char *base,
308 struct ref_array *array)
310 DIR *dir;
311 const char *path;
313 if (*refs->name)
314 path = git_path_submodule(refs->name, "%s", base);
315 else
316 path = git_path("%s", base);
319 dir = opendir(path);
321 if (dir) {
322 struct dirent *de;
323 int baselen = strlen(base);
324 char *refname = xmalloc(baselen + 257);
326 memcpy(refname, base, baselen);
327 if (baselen && base[baselen-1] != '/')
328 refname[baselen++] = '/';
330 while ((de = readdir(dir)) != NULL) {
331 unsigned char sha1[20];
332 struct stat st;
333 int flag;
334 int namelen;
335 const char *refdir;
337 if (de->d_name[0] == '.')
338 continue;
339 namelen = strlen(de->d_name);
340 if (namelen > 255)
341 continue;
342 if (has_extension(de->d_name, ".lock"))
343 continue;
344 memcpy(refname + baselen, de->d_name, namelen+1);
345 refdir = *refs->name
346 ? git_path_submodule(refs->name, "%s", refname)
347 : git_path("%s", refname);
348 if (stat(refdir, &st) < 0)
349 continue;
350 if (S_ISDIR(st.st_mode)) {
351 get_ref_dir(refs, refname, array);
352 continue;
354 if (*refs->name) {
355 hashclr(sha1);
356 flag = 0;
357 if (resolve_gitlink_ref(refs->name, refname, sha1) < 0) {
358 hashclr(sha1);
359 flag |= REF_ISBROKEN;
361 } else
362 if (!resolve_ref(refname, sha1, 1, &flag)) {
363 hashclr(sha1);
364 flag |= REF_ISBROKEN;
366 add_ref(array, create_ref_entry(refname, sha1, flag));
368 free(refname);
369 closedir(dir);
373 struct warn_if_dangling_data {
374 FILE *fp;
375 const char *refname;
376 const char *msg_fmt;
379 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
380 int flags, void *cb_data)
382 struct warn_if_dangling_data *d = cb_data;
383 const char *resolves_to;
384 unsigned char junk[20];
386 if (!(flags & REF_ISSYMREF))
387 return 0;
389 resolves_to = resolve_ref(refname, junk, 0, NULL);
390 if (!resolves_to || strcmp(resolves_to, d->refname))
391 return 0;
393 fprintf(d->fp, d->msg_fmt, refname);
394 return 0;
397 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
399 struct warn_if_dangling_data data;
401 data.fp = fp;
402 data.refname = refname;
403 data.msg_fmt = msg_fmt;
404 for_each_rawref(warn_if_dangling_symref, &data);
407 static struct ref_array *get_loose_refs(struct ref_cache *refs)
409 if (!refs->did_loose) {
410 get_ref_dir(refs, "refs", &refs->loose);
411 sort_ref_array(&refs->loose);
412 refs->did_loose = 1;
414 return &refs->loose;
417 /* We allow "recursive" symbolic refs. Only within reason, though */
418 #define MAXDEPTH 5
419 #define MAXREFLEN (1024)
421 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
422 const char *refname, unsigned char *sha1)
424 int retval = -1;
425 struct ref_entry *ref;
426 struct ref_array *array = get_packed_refs(refs);
428 ref = search_ref_array(array, refname);
429 if (ref != NULL) {
430 memcpy(sha1, ref->sha1, 20);
431 retval = 0;
433 return retval;
436 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
437 const char *refname, unsigned char *sha1,
438 int recursion)
440 int fd, len;
441 char buffer[128], *p;
442 char *path;
444 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
445 return -1;
446 path = *refs->name
447 ? git_path_submodule(refs->name, "%s", refname)
448 : git_path("%s", refname);
449 fd = open(path, O_RDONLY);
450 if (fd < 0)
451 return resolve_gitlink_packed_ref(refs, refname, sha1);
453 len = read(fd, buffer, sizeof(buffer)-1);
454 close(fd);
455 if (len < 0)
456 return -1;
457 while (len && isspace(buffer[len-1]))
458 len--;
459 buffer[len] = 0;
461 /* Was it a detached head or an old-fashioned symlink? */
462 if (!get_sha1_hex(buffer, sha1))
463 return 0;
465 /* Symref? */
466 if (strncmp(buffer, "ref:", 4))
467 return -1;
468 p = buffer + 4;
469 while (isspace(*p))
470 p++;
472 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
475 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
477 int len = strlen(path), retval;
478 char *submodule;
479 struct ref_cache *refs;
481 while (len && path[len-1] == '/')
482 len--;
483 if (!len)
484 return -1;
485 submodule = xstrndup(path, len);
486 refs = get_ref_cache(submodule);
487 free(submodule);
489 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
490 return retval;
494 * Try to read ref from the packed references. On success, set sha1
495 * and return 0; otherwise, return -1.
497 static int get_packed_ref(const char *refname, unsigned char *sha1)
499 struct ref_array *packed = get_packed_refs(get_ref_cache(NULL));
500 struct ref_entry *entry = search_ref_array(packed, refname);
501 if (entry) {
502 hashcpy(sha1, entry->sha1);
503 return 0;
505 return -1;
508 const char *resolve_ref(const char *refname, unsigned char *sha1, int reading, int *flag)
510 int depth = MAXDEPTH;
511 ssize_t len;
512 char buffer[256];
513 static char refname_buffer[256];
515 if (flag)
516 *flag = 0;
518 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
519 return NULL;
521 for (;;) {
522 char path[PATH_MAX];
523 struct stat st;
524 char *buf;
525 int fd;
527 if (--depth < 0)
528 return NULL;
530 git_snpath(path, sizeof(path), "%s", refname);
532 if (lstat(path, &st) < 0) {
533 if (errno != ENOENT)
534 return NULL;
536 * The loose reference file does not exist;
537 * check for a packed reference.
539 if (!get_packed_ref(refname, sha1)) {
540 if (flag)
541 *flag |= REF_ISPACKED;
542 return refname;
544 /* The reference is not a packed reference, either. */
545 if (reading) {
546 return NULL;
547 } else {
548 hashclr(sha1);
549 return refname;
553 /* Follow "normalized" - ie "refs/.." symlinks by hand */
554 if (S_ISLNK(st.st_mode)) {
555 len = readlink(path, buffer, sizeof(buffer)-1);
556 if (len < 0)
557 return NULL;
558 buffer[len] = 0;
559 if (!prefixcmp(buffer, "refs/") &&
560 !check_refname_format(buffer, 0)) {
561 strcpy(refname_buffer, buffer);
562 refname = refname_buffer;
563 if (flag)
564 *flag |= REF_ISSYMREF;
565 continue;
569 /* Is it a directory? */
570 if (S_ISDIR(st.st_mode)) {
571 errno = EISDIR;
572 return NULL;
576 * Anything else, just open it and try to use it as
577 * a ref
579 fd = open(path, O_RDONLY);
580 if (fd < 0)
581 return NULL;
582 len = read_in_full(fd, buffer, sizeof(buffer)-1);
583 close(fd);
584 if (len < 0)
585 return NULL;
586 while (len && isspace(buffer[len-1]))
587 len--;
588 buffer[len] = '\0';
591 * Is it a symbolic ref?
593 if (prefixcmp(buffer, "ref:"))
594 break;
595 if (flag)
596 *flag |= REF_ISSYMREF;
597 buf = buffer + 4;
598 while (isspace(*buf))
599 buf++;
600 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
601 if (flag)
602 *flag |= REF_ISBROKEN;
603 return NULL;
605 refname = strcpy(refname_buffer, buf);
607 /* Please note that FETCH_HEAD has a second line containing other data. */
608 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
609 if (flag)
610 *flag |= REF_ISBROKEN;
611 return NULL;
613 return refname;
616 /* The argument to filter_refs */
617 struct ref_filter {
618 const char *pattern;
619 each_ref_fn *fn;
620 void *cb_data;
623 int read_ref(const char *refname, unsigned char *sha1)
625 if (resolve_ref(refname, sha1, 1, NULL))
626 return 0;
627 return -1;
630 #define DO_FOR_EACH_INCLUDE_BROKEN 01
631 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
632 int flags, void *cb_data, struct ref_entry *entry)
634 if (prefixcmp(entry->name, base))
635 return 0;
637 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
638 if (entry->flag & REF_ISBROKEN)
639 return 0; /* ignore broken refs e.g. dangling symref */
640 if (!has_sha1_file(entry->sha1)) {
641 error("%s does not point to a valid object!", entry->name);
642 return 0;
645 current_ref = entry;
646 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
649 static int filter_refs(const char *refname, const unsigned char *sha, int flags,
650 void *data)
652 struct ref_filter *filter = (struct ref_filter *)data;
653 if (fnmatch(filter->pattern, refname, 0))
654 return 0;
655 return filter->fn(refname, sha, flags, filter->cb_data);
658 int peel_ref(const char *refname, unsigned char *sha1)
660 int flag;
661 unsigned char base[20];
662 struct object *o;
664 if (current_ref && (current_ref->name == refname
665 || !strcmp(current_ref->name, refname))) {
666 if (current_ref->flag & REF_KNOWS_PEELED) {
667 hashcpy(sha1, current_ref->peeled);
668 return 0;
670 hashcpy(base, current_ref->sha1);
671 goto fallback;
674 if (!resolve_ref(refname, base, 1, &flag))
675 return -1;
677 if ((flag & REF_ISPACKED)) {
678 struct ref_array *array = get_packed_refs(get_ref_cache(NULL));
679 struct ref_entry *r = search_ref_array(array, refname);
681 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
682 hashcpy(sha1, r->peeled);
683 return 0;
687 fallback:
688 o = parse_object(base);
689 if (o && o->type == OBJ_TAG) {
690 o = deref_tag(o, refname, 0);
691 if (o) {
692 hashcpy(sha1, o->sha1);
693 return 0;
696 return -1;
699 static int do_for_each_ref_in_array(struct ref_array *array, int offset,
700 const char *base,
701 each_ref_fn fn, int trim, int flags, void *cb_data)
703 int i;
704 for (i = offset; i < array->nr; i++) {
705 int retval = do_one_ref(base, fn, trim, flags, cb_data, array->refs[i]);
706 if (retval)
707 return retval;
709 return 0;
712 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
713 int trim, int flags, void *cb_data)
715 int retval = 0, p = 0, l = 0;
716 struct ref_cache *refs = get_ref_cache(submodule);
717 struct ref_array *packed = get_packed_refs(refs);
718 struct ref_array *loose = get_loose_refs(refs);
720 retval = do_for_each_ref_in_array(&extra_refs, 0,
721 base, fn, trim, flags, cb_data);
722 if (retval)
723 goto end_each;
725 while (p < packed->nr && l < loose->nr) {
726 struct ref_entry *entry;
727 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
728 if (!cmp) {
729 p++;
730 continue;
732 if (cmp > 0) {
733 entry = loose->refs[l++];
734 } else {
735 entry = packed->refs[p++];
737 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
738 if (retval)
739 goto end_each;
742 if (l < loose->nr) {
743 retval = do_for_each_ref_in_array(loose, l,
744 base, fn, trim, flags, cb_data);
745 } else {
746 retval = do_for_each_ref_in_array(packed, p,
747 base, fn, trim, flags, cb_data);
750 end_each:
751 current_ref = NULL;
752 return retval;
756 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
758 unsigned char sha1[20];
759 int flag;
761 if (submodule) {
762 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
763 return fn("HEAD", sha1, 0, cb_data);
765 return 0;
768 if (resolve_ref("HEAD", sha1, 1, &flag))
769 return fn("HEAD", sha1, flag, cb_data);
771 return 0;
774 int head_ref(each_ref_fn fn, void *cb_data)
776 return do_head_ref(NULL, fn, cb_data);
779 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
781 return do_head_ref(submodule, fn, cb_data);
784 int for_each_ref(each_ref_fn fn, void *cb_data)
786 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
789 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
791 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
794 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
796 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
799 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
800 each_ref_fn fn, void *cb_data)
802 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
805 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
807 return for_each_ref_in("refs/tags/", fn, cb_data);
810 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
812 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
815 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
817 return for_each_ref_in("refs/heads/", fn, cb_data);
820 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
822 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
825 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
827 return for_each_ref_in("refs/remotes/", fn, cb_data);
830 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
832 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
835 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
837 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
840 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
842 struct strbuf buf = STRBUF_INIT;
843 int ret = 0;
844 unsigned char sha1[20];
845 int flag;
847 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
848 if (resolve_ref(buf.buf, sha1, 1, &flag))
849 ret = fn(buf.buf, sha1, flag, cb_data);
850 strbuf_release(&buf);
852 return ret;
855 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
857 struct strbuf buf = STRBUF_INIT;
858 int ret;
859 strbuf_addf(&buf, "%srefs/", get_git_namespace());
860 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
861 strbuf_release(&buf);
862 return ret;
865 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
866 const char *prefix, void *cb_data)
868 struct strbuf real_pattern = STRBUF_INIT;
869 struct ref_filter filter;
870 int ret;
872 if (!prefix && prefixcmp(pattern, "refs/"))
873 strbuf_addstr(&real_pattern, "refs/");
874 else if (prefix)
875 strbuf_addstr(&real_pattern, prefix);
876 strbuf_addstr(&real_pattern, pattern);
878 if (!has_glob_specials(pattern)) {
879 /* Append implied '/' '*' if not present. */
880 if (real_pattern.buf[real_pattern.len - 1] != '/')
881 strbuf_addch(&real_pattern, '/');
882 /* No need to check for '*', there is none. */
883 strbuf_addch(&real_pattern, '*');
886 filter.pattern = real_pattern.buf;
887 filter.fn = fn;
888 filter.cb_data = cb_data;
889 ret = for_each_ref(filter_refs, &filter);
891 strbuf_release(&real_pattern);
892 return ret;
895 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
897 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
900 int for_each_rawref(each_ref_fn fn, void *cb_data)
902 return do_for_each_ref(NULL, "", fn, 0,
903 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
907 * Make sure "ref" is something reasonable to have under ".git/refs/";
908 * We do not like it if:
910 * - any path component of it begins with ".", or
911 * - it has double dots "..", or
912 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
913 * - it ends with a "/".
914 * - it ends with ".lock"
915 * - it contains a "\" (backslash)
918 /* Return true iff ch is not allowed in reference names. */
919 static inline int bad_ref_char(int ch)
921 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
922 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
923 return 1;
924 /* 2.13 Pattern Matching Notation */
925 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
926 return 1;
927 return 0;
931 * Try to read one refname component from the front of refname. Return
932 * the length of the component found, or -1 if the component is not
933 * legal.
935 static int check_refname_component(const char *refname, int flags)
937 const char *cp;
938 char last = '\0';
940 for (cp = refname; ; cp++) {
941 char ch = *cp;
942 if (ch == '\0' || ch == '/')
943 break;
944 if (bad_ref_char(ch))
945 return -1; /* Illegal character in refname. */
946 if (last == '.' && ch == '.')
947 return -1; /* Refname contains "..". */
948 if (last == '@' && ch == '{')
949 return -1; /* Refname contains "@{". */
950 last = ch;
952 if (cp == refname)
953 return -1; /* Component has zero length. */
954 if (refname[0] == '.') {
955 if (!(flags & REFNAME_DOT_COMPONENT))
956 return -1; /* Component starts with '.'. */
958 * Even if leading dots are allowed, don't allow "."
959 * as a component (".." is prevented by a rule above).
961 if (refname[1] == '\0')
962 return -1; /* Component equals ".". */
964 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
965 return -1; /* Refname ends with ".lock". */
966 return cp - refname;
969 int check_refname_format(const char *refname, int flags)
971 int component_len, component_count = 0;
973 while (1) {
974 /* We are at the start of a path component. */
975 component_len = check_refname_component(refname, flags);
976 if (component_len < 0) {
977 if ((flags & REFNAME_REFSPEC_PATTERN) &&
978 refname[0] == '*' &&
979 (refname[1] == '\0' || refname[1] == '/')) {
980 /* Accept one wildcard as a full refname component. */
981 flags &= ~REFNAME_REFSPEC_PATTERN;
982 component_len = 1;
983 } else {
984 return -1;
987 component_count++;
988 if (refname[component_len] == '\0')
989 break;
990 /* Skip to next component. */
991 refname += component_len + 1;
994 if (refname[component_len - 1] == '.')
995 return -1; /* Refname ends with '.'. */
996 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
997 return -1; /* Refname has only one component. */
998 return 0;
1001 const char *prettify_refname(const char *name)
1003 return name + (
1004 !prefixcmp(name, "refs/heads/") ? 11 :
1005 !prefixcmp(name, "refs/tags/") ? 10 :
1006 !prefixcmp(name, "refs/remotes/") ? 13 :
1010 const char *ref_rev_parse_rules[] = {
1011 "%.*s",
1012 "refs/%.*s",
1013 "refs/tags/%.*s",
1014 "refs/heads/%.*s",
1015 "refs/remotes/%.*s",
1016 "refs/remotes/%.*s/HEAD",
1017 NULL
1020 const char *ref_fetch_rules[] = {
1021 "%.*s",
1022 "refs/%.*s",
1023 "refs/heads/%.*s",
1024 NULL
1027 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1029 const char **p;
1030 const int abbrev_name_len = strlen(abbrev_name);
1032 for (p = rules; *p; p++) {
1033 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1034 return 1;
1038 return 0;
1041 static struct ref_lock *verify_lock(struct ref_lock *lock,
1042 const unsigned char *old_sha1, int mustexist)
1044 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1045 error("Can't verify ref %s", lock->ref_name);
1046 unlock_ref(lock);
1047 return NULL;
1049 if (hashcmp(lock->old_sha1, old_sha1)) {
1050 error("Ref %s is at %s but expected %s", lock->ref_name,
1051 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1052 unlock_ref(lock);
1053 return NULL;
1055 return lock;
1058 static int remove_empty_directories(const char *file)
1060 /* we want to create a file but there is a directory there;
1061 * if that is an empty directory (or a directory that contains
1062 * only empty directories), remove them.
1064 struct strbuf path;
1065 int result;
1067 strbuf_init(&path, 20);
1068 strbuf_addstr(&path, file);
1070 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1072 strbuf_release(&path);
1074 return result;
1078 * Return true iff refname1 and refname2 conflict with each other.
1079 * Two reference names conflict if one of them exactly matches the
1080 * leading components of the other; e.g., "foo/bar" conflicts with
1081 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
1082 * "foo/barbados".
1084 static int names_conflict(const char *refname1, const char *refname2)
1086 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
1088 return (*refname1 == '\0' && *refname2 == '/')
1089 || (*refname1 == '/' && *refname2 == '\0');
1092 struct name_conflict_cb {
1093 const char *refname;
1094 const char *oldrefname;
1095 const char *conflicting_refname;
1098 static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
1099 int flags, void *cb_data)
1101 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
1102 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
1103 return 0;
1104 if (names_conflict(data->refname, existingrefname)) {
1105 data->conflicting_refname = existingrefname;
1106 return 1;
1108 return 0;
1112 * Return true iff a reference named refname could be created without
1113 * conflicting with the name of an existing reference. If oldrefname
1114 * is non-NULL, ignore potential conflicts with oldrefname (e.g.,
1115 * because oldrefname is scheduled for deletion in the same
1116 * operation).
1118 static int is_refname_available(const char *refname, const char *oldrefname,
1119 struct ref_array *array)
1121 struct name_conflict_cb data;
1122 data.refname = refname;
1123 data.oldrefname = oldrefname;
1124 data.conflicting_refname = NULL;
1126 if (do_for_each_ref_in_array(array, 0, "", name_conflict_fn,
1127 0, DO_FOR_EACH_INCLUDE_BROKEN,
1128 &data)) {
1129 error("'%s' exists; cannot create '%s'",
1130 data.conflicting_refname, refname);
1131 return 0;
1133 return 1;
1137 * *string and *len will only be substituted, and *string returned (for
1138 * later free()ing) if the string passed in is a magic short-hand form
1139 * to name a branch.
1141 static char *substitute_branch_name(const char **string, int *len)
1143 struct strbuf buf = STRBUF_INIT;
1144 int ret = interpret_branch_name(*string, &buf);
1146 if (ret == *len) {
1147 size_t size;
1148 *string = strbuf_detach(&buf, &size);
1149 *len = size;
1150 return (char *)*string;
1153 return NULL;
1156 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1158 char *last_branch = substitute_branch_name(&str, &len);
1159 const char **p, *r;
1160 int refs_found = 0;
1162 *ref = NULL;
1163 for (p = ref_rev_parse_rules; *p; p++) {
1164 char fullref[PATH_MAX];
1165 unsigned char sha1_from_ref[20];
1166 unsigned char *this_result;
1167 int flag;
1169 this_result = refs_found ? sha1_from_ref : sha1;
1170 mksnpath(fullref, sizeof(fullref), *p, len, str);
1171 r = resolve_ref(fullref, this_result, 1, &flag);
1172 if (r) {
1173 if (!refs_found++)
1174 *ref = xstrdup(r);
1175 if (!warn_ambiguous_refs)
1176 break;
1177 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1178 warning("ignoring dangling symref %s.", fullref);
1179 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1180 warning("ignoring broken ref %s.", fullref);
1183 free(last_branch);
1184 return refs_found;
1187 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1189 char *last_branch = substitute_branch_name(&str, &len);
1190 const char **p;
1191 int logs_found = 0;
1193 *log = NULL;
1194 for (p = ref_rev_parse_rules; *p; p++) {
1195 struct stat st;
1196 unsigned char hash[20];
1197 char path[PATH_MAX];
1198 const char *ref, *it;
1200 mksnpath(path, sizeof(path), *p, len, str);
1201 ref = resolve_ref(path, hash, 1, NULL);
1202 if (!ref)
1203 continue;
1204 if (!stat(git_path("logs/%s", path), &st) &&
1205 S_ISREG(st.st_mode))
1206 it = path;
1207 else if (strcmp(ref, path) &&
1208 !stat(git_path("logs/%s", ref), &st) &&
1209 S_ISREG(st.st_mode))
1210 it = ref;
1211 else
1212 continue;
1213 if (!logs_found++) {
1214 *log = xstrdup(it);
1215 hashcpy(sha1, hash);
1217 if (!warn_ambiguous_refs)
1218 break;
1220 free(last_branch);
1221 return logs_found;
1224 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1225 const unsigned char *old_sha1,
1226 int flags, int *type_p)
1228 char *ref_file;
1229 const char *orig_refname = refname;
1230 struct ref_lock *lock;
1231 int last_errno = 0;
1232 int type, lflags;
1233 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1234 int missing = 0;
1236 lock = xcalloc(1, sizeof(struct ref_lock));
1237 lock->lock_fd = -1;
1239 refname = resolve_ref(refname, lock->old_sha1, mustexist, &type);
1240 if (!refname && errno == EISDIR) {
1241 /* we are trying to lock foo but we used to
1242 * have foo/bar which now does not exist;
1243 * it is normal for the empty directory 'foo'
1244 * to remain.
1246 ref_file = git_path("%s", orig_refname);
1247 if (remove_empty_directories(ref_file)) {
1248 last_errno = errno;
1249 error("there are still refs under '%s'", orig_refname);
1250 goto error_return;
1252 refname = resolve_ref(orig_refname, lock->old_sha1, mustexist, &type);
1254 if (type_p)
1255 *type_p = type;
1256 if (!refname) {
1257 last_errno = errno;
1258 error("unable to resolve reference %s: %s",
1259 orig_refname, strerror(errno));
1260 goto error_return;
1262 missing = is_null_sha1(lock->old_sha1);
1263 /* When the ref did not exist and we are creating it,
1264 * make sure there is no existing ref that is packed
1265 * whose name begins with our refname, nor a ref whose
1266 * name is a proper prefix of our refname.
1268 if (missing &&
1269 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
1270 last_errno = ENOTDIR;
1271 goto error_return;
1274 lock->lk = xcalloc(1, sizeof(struct lock_file));
1276 lflags = LOCK_DIE_ON_ERROR;
1277 if (flags & REF_NODEREF) {
1278 refname = orig_refname;
1279 lflags |= LOCK_NODEREF;
1281 lock->ref_name = xstrdup(refname);
1282 lock->orig_ref_name = xstrdup(orig_refname);
1283 ref_file = git_path("%s", refname);
1284 if (missing)
1285 lock->force_write = 1;
1286 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1287 lock->force_write = 1;
1289 if (safe_create_leading_directories(ref_file)) {
1290 last_errno = errno;
1291 error("unable to create directory for %s", ref_file);
1292 goto error_return;
1295 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1296 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1298 error_return:
1299 unlock_ref(lock);
1300 errno = last_errno;
1301 return NULL;
1304 struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
1306 char refpath[PATH_MAX];
1307 if (check_refname_format(refname, 0))
1308 return NULL;
1309 strcpy(refpath, mkpath("refs/%s", refname));
1310 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1313 struct ref_lock *lock_any_ref_for_update(const char *refname,
1314 const unsigned char *old_sha1, int flags)
1316 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1317 return NULL;
1318 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
1321 struct repack_without_ref_sb {
1322 const char *refname;
1323 int fd;
1326 static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1327 int flags, void *cb_data)
1329 struct repack_without_ref_sb *data = cb_data;
1330 char line[PATH_MAX + 100];
1331 int len;
1333 if (!strcmp(data->refname, refname))
1334 return 0;
1335 len = snprintf(line, sizeof(line), "%s %s\n",
1336 sha1_to_hex(sha1), refname);
1337 /* this should not happen but just being defensive */
1338 if (len > sizeof(line))
1339 die("too long a refname '%s'", refname);
1340 write_or_die(data->fd, line, len);
1341 return 0;
1344 static struct lock_file packlock;
1346 static int repack_without_ref(const char *refname)
1348 struct repack_without_ref_sb data;
1349 struct ref_array *packed;
1351 packed = get_packed_refs(get_ref_cache(NULL));
1352 if (search_ref_array(packed, refname) == NULL)
1353 return 0;
1354 data.refname = refname;
1355 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1356 if (data.fd < 0) {
1357 unable_to_lock_error(git_path("packed-refs"), errno);
1358 return error("cannot delete '%s' from packed refs", refname);
1360 do_for_each_ref_in_array(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
1361 return commit_lock_file(&packlock);
1364 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1366 struct ref_lock *lock;
1367 int err, i = 0, ret = 0, flag = 0;
1369 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1370 if (!lock)
1371 return 1;
1372 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1373 /* loose */
1374 const char *path;
1376 if (!(delopt & REF_NODEREF)) {
1377 i = strlen(lock->lk->filename) - 5; /* .lock */
1378 lock->lk->filename[i] = 0;
1379 path = lock->lk->filename;
1380 } else {
1381 path = git_path("%s", refname);
1383 err = unlink_or_warn(path);
1384 if (err && errno != ENOENT)
1385 ret = 1;
1387 if (!(delopt & REF_NODEREF))
1388 lock->lk->filename[i] = '.';
1390 /* removing the loose one could have resurrected an earlier
1391 * packed one. Also, if it was not loose we need to repack
1392 * without it.
1394 ret |= repack_without_ref(refname);
1396 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1397 invalidate_ref_cache(NULL);
1398 unlock_ref(lock);
1399 return ret;
1403 * People using contrib's git-new-workdir have .git/logs/refs ->
1404 * /some/other/path/.git/logs/refs, and that may live on another device.
1406 * IOW, to avoid cross device rename errors, the temporary renamed log must
1407 * live into logs/refs.
1409 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1411 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
1413 unsigned char sha1[20], orig_sha1[20];
1414 int flag = 0, logmoved = 0;
1415 struct ref_lock *lock;
1416 struct stat loginfo;
1417 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
1418 const char *symref = NULL;
1419 struct ref_cache *refs = get_ref_cache(NULL);
1421 if (log && S_ISLNK(loginfo.st_mode))
1422 return error("reflog for %s is a symlink", oldrefname);
1424 symref = resolve_ref(oldrefname, orig_sha1, 1, &flag);
1425 if (flag & REF_ISSYMREF)
1426 return error("refname %s is a symbolic ref, renaming it is not supported",
1427 oldrefname);
1428 if (!symref)
1429 return error("refname %s not found", oldrefname);
1431 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
1432 return 1;
1434 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
1435 return 1;
1437 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
1438 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1439 oldrefname, strerror(errno));
1441 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1442 error("unable to delete old %s", oldrefname);
1443 goto rollback;
1446 if (resolve_ref(newrefname, sha1, 1, &flag) && delete_ref(newrefname, sha1, REF_NODEREF)) {
1447 if (errno==EISDIR) {
1448 if (remove_empty_directories(git_path("%s", newrefname))) {
1449 error("Directory not empty: %s", newrefname);
1450 goto rollback;
1452 } else {
1453 error("unable to delete existing %s", newrefname);
1454 goto rollback;
1458 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1459 error("unable to create directory for %s", newrefname);
1460 goto rollback;
1463 retry:
1464 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
1465 if (errno==EISDIR || errno==ENOTDIR) {
1467 * rename(a, b) when b is an existing
1468 * directory ought to result in ISDIR, but
1469 * Solaris 5.8 gives ENOTDIR. Sheesh.
1471 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1472 error("Directory not empty: logs/%s", newrefname);
1473 goto rollback;
1475 goto retry;
1476 } else {
1477 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1478 newrefname, strerror(errno));
1479 goto rollback;
1482 logmoved = log;
1484 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
1485 if (!lock) {
1486 error("unable to lock %s for update", newrefname);
1487 goto rollback;
1489 lock->force_write = 1;
1490 hashcpy(lock->old_sha1, orig_sha1);
1491 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1492 error("unable to write current sha1 into %s", newrefname);
1493 goto rollback;
1496 return 0;
1498 rollback:
1499 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
1500 if (!lock) {
1501 error("unable to lock %s for rollback", oldrefname);
1502 goto rollbacklog;
1505 lock->force_write = 1;
1506 flag = log_all_ref_updates;
1507 log_all_ref_updates = 0;
1508 if (write_ref_sha1(lock, orig_sha1, NULL))
1509 error("unable to write current sha1 into %s", oldrefname);
1510 log_all_ref_updates = flag;
1512 rollbacklog:
1513 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
1514 error("unable to restore logfile %s from %s: %s",
1515 oldrefname, newrefname, strerror(errno));
1516 if (!logmoved && log &&
1517 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
1518 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1519 oldrefname, strerror(errno));
1521 return 1;
1524 int close_ref(struct ref_lock *lock)
1526 if (close_lock_file(lock->lk))
1527 return -1;
1528 lock->lock_fd = -1;
1529 return 0;
1532 int commit_ref(struct ref_lock *lock)
1534 if (commit_lock_file(lock->lk))
1535 return -1;
1536 lock->lock_fd = -1;
1537 return 0;
1540 void unlock_ref(struct ref_lock *lock)
1542 /* Do not free lock->lk -- atexit() still looks at them */
1543 if (lock->lk)
1544 rollback_lock_file(lock->lk);
1545 free(lock->ref_name);
1546 free(lock->orig_ref_name);
1547 free(lock);
1551 * copy the reflog message msg to buf, which has been allocated sufficiently
1552 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1553 * because reflog file is one line per entry.
1555 static int copy_msg(char *buf, const char *msg)
1557 char *cp = buf;
1558 char c;
1559 int wasspace = 1;
1561 *cp++ = '\t';
1562 while ((c = *msg++)) {
1563 if (wasspace && isspace(c))
1564 continue;
1565 wasspace = isspace(c);
1566 if (wasspace)
1567 c = ' ';
1568 *cp++ = c;
1570 while (buf < cp && isspace(cp[-1]))
1571 cp--;
1572 *cp++ = '\n';
1573 return cp - buf;
1576 int log_ref_setup(const char *refname, char *logfile, int bufsize)
1578 int logfd, oflags = O_APPEND | O_WRONLY;
1580 git_snpath(logfile, bufsize, "logs/%s", refname);
1581 if (log_all_ref_updates &&
1582 (!prefixcmp(refname, "refs/heads/") ||
1583 !prefixcmp(refname, "refs/remotes/") ||
1584 !prefixcmp(refname, "refs/notes/") ||
1585 !strcmp(refname, "HEAD"))) {
1586 if (safe_create_leading_directories(logfile) < 0)
1587 return error("unable to create directory for %s",
1588 logfile);
1589 oflags |= O_CREAT;
1592 logfd = open(logfile, oflags, 0666);
1593 if (logfd < 0) {
1594 if (!(oflags & O_CREAT) && errno == ENOENT)
1595 return 0;
1597 if ((oflags & O_CREAT) && errno == EISDIR) {
1598 if (remove_empty_directories(logfile)) {
1599 return error("There are still logs under '%s'",
1600 logfile);
1602 logfd = open(logfile, oflags, 0666);
1605 if (logfd < 0)
1606 return error("Unable to append to %s: %s",
1607 logfile, strerror(errno));
1610 adjust_shared_perm(logfile);
1611 close(logfd);
1612 return 0;
1615 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
1616 const unsigned char *new_sha1, const char *msg)
1618 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1619 unsigned maxlen, len;
1620 int msglen;
1621 char log_file[PATH_MAX];
1622 char *logrec;
1623 const char *committer;
1625 if (log_all_ref_updates < 0)
1626 log_all_ref_updates = !is_bare_repository();
1628 result = log_ref_setup(refname, log_file, sizeof(log_file));
1629 if (result)
1630 return result;
1632 logfd = open(log_file, oflags);
1633 if (logfd < 0)
1634 return 0;
1635 msglen = msg ? strlen(msg) : 0;
1636 committer = git_committer_info(0);
1637 maxlen = strlen(committer) + msglen + 100;
1638 logrec = xmalloc(maxlen);
1639 len = sprintf(logrec, "%s %s %s\n",
1640 sha1_to_hex(old_sha1),
1641 sha1_to_hex(new_sha1),
1642 committer);
1643 if (msglen)
1644 len += copy_msg(logrec + len - 1, msg) - 1;
1645 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1646 free(logrec);
1647 if (close(logfd) != 0 || written != len)
1648 return error("Unable to append to %s", log_file);
1649 return 0;
1652 static int is_branch(const char *refname)
1654 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1657 int write_ref_sha1(struct ref_lock *lock,
1658 const unsigned char *sha1, const char *logmsg)
1660 static char term = '\n';
1661 struct object *o;
1663 if (!lock)
1664 return -1;
1665 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1666 unlock_ref(lock);
1667 return 0;
1669 o = parse_object(sha1);
1670 if (!o) {
1671 error("Trying to write ref %s with nonexistent object %s",
1672 lock->ref_name, sha1_to_hex(sha1));
1673 unlock_ref(lock);
1674 return -1;
1676 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1677 error("Trying to write non-commit object %s to branch %s",
1678 sha1_to_hex(sha1), lock->ref_name);
1679 unlock_ref(lock);
1680 return -1;
1682 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1683 write_in_full(lock->lock_fd, &term, 1) != 1
1684 || close_ref(lock) < 0) {
1685 error("Couldn't write %s", lock->lk->filename);
1686 unlock_ref(lock);
1687 return -1;
1689 clear_loose_ref_cache(get_ref_cache(NULL));
1690 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1691 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1692 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1693 unlock_ref(lock);
1694 return -1;
1696 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1698 * Special hack: If a branch is updated directly and HEAD
1699 * points to it (may happen on the remote side of a push
1700 * for example) then logically the HEAD reflog should be
1701 * updated too.
1702 * A generic solution implies reverse symref information,
1703 * but finding all symrefs pointing to the given branch
1704 * would be rather costly for this rare event (the direct
1705 * update of a branch) to be worth it. So let's cheat and
1706 * check with HEAD only which should cover 99% of all usage
1707 * scenarios (even 100% of the default ones).
1709 unsigned char head_sha1[20];
1710 int head_flag;
1711 const char *head_ref;
1712 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1713 if (head_ref && (head_flag & REF_ISSYMREF) &&
1714 !strcmp(head_ref, lock->ref_name))
1715 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1717 if (commit_ref(lock)) {
1718 error("Couldn't set %s", lock->ref_name);
1719 unlock_ref(lock);
1720 return -1;
1722 unlock_ref(lock);
1723 return 0;
1726 int create_symref(const char *ref_target, const char *refs_heads_master,
1727 const char *logmsg)
1729 const char *lockpath;
1730 char ref[1000];
1731 int fd, len, written;
1732 char *git_HEAD = git_pathdup("%s", ref_target);
1733 unsigned char old_sha1[20], new_sha1[20];
1735 if (logmsg && read_ref(ref_target, old_sha1))
1736 hashclr(old_sha1);
1738 if (safe_create_leading_directories(git_HEAD) < 0)
1739 return error("unable to create directory for %s", git_HEAD);
1741 #ifndef NO_SYMLINK_HEAD
1742 if (prefer_symlink_refs) {
1743 unlink(git_HEAD);
1744 if (!symlink(refs_heads_master, git_HEAD))
1745 goto done;
1746 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1748 #endif
1750 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1751 if (sizeof(ref) <= len) {
1752 error("refname too long: %s", refs_heads_master);
1753 goto error_free_return;
1755 lockpath = mkpath("%s.lock", git_HEAD);
1756 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1757 if (fd < 0) {
1758 error("Unable to open %s for writing", lockpath);
1759 goto error_free_return;
1761 written = write_in_full(fd, ref, len);
1762 if (close(fd) != 0 || written != len) {
1763 error("Unable to write to %s", lockpath);
1764 goto error_unlink_return;
1766 if (rename(lockpath, git_HEAD) < 0) {
1767 error("Unable to create %s", git_HEAD);
1768 goto error_unlink_return;
1770 if (adjust_shared_perm(git_HEAD)) {
1771 error("Unable to fix permissions on %s", lockpath);
1772 error_unlink_return:
1773 unlink_or_warn(lockpath);
1774 error_free_return:
1775 free(git_HEAD);
1776 return -1;
1779 #ifndef NO_SYMLINK_HEAD
1780 done:
1781 #endif
1782 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1783 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1785 free(git_HEAD);
1786 return 0;
1789 static char *ref_msg(const char *line, const char *endp)
1791 const char *ep;
1792 line += 82;
1793 ep = memchr(line, '\n', endp - line);
1794 if (!ep)
1795 ep = endp;
1796 return xmemdupz(line, ep - line);
1799 int read_ref_at(const char *refname, unsigned long at_time, int cnt,
1800 unsigned char *sha1, char **msg,
1801 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1803 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1804 char *tz_c;
1805 int logfd, tz, reccnt = 0;
1806 struct stat st;
1807 unsigned long date;
1808 unsigned char logged_sha1[20];
1809 void *log_mapped;
1810 size_t mapsz;
1812 logfile = git_path("logs/%s", refname);
1813 logfd = open(logfile, O_RDONLY, 0);
1814 if (logfd < 0)
1815 die_errno("Unable to read log '%s'", logfile);
1816 fstat(logfd, &st);
1817 if (!st.st_size)
1818 die("Log %s is empty.", logfile);
1819 mapsz = xsize_t(st.st_size);
1820 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1821 logdata = log_mapped;
1822 close(logfd);
1824 lastrec = NULL;
1825 rec = logend = logdata + st.st_size;
1826 while (logdata < rec) {
1827 reccnt++;
1828 if (logdata < rec && *(rec-1) == '\n')
1829 rec--;
1830 lastgt = NULL;
1831 while (logdata < rec && *(rec-1) != '\n') {
1832 rec--;
1833 if (*rec == '>')
1834 lastgt = rec;
1836 if (!lastgt)
1837 die("Log %s is corrupt.", logfile);
1838 date = strtoul(lastgt + 1, &tz_c, 10);
1839 if (date <= at_time || cnt == 0) {
1840 tz = strtoul(tz_c, NULL, 10);
1841 if (msg)
1842 *msg = ref_msg(rec, logend);
1843 if (cutoff_time)
1844 *cutoff_time = date;
1845 if (cutoff_tz)
1846 *cutoff_tz = tz;
1847 if (cutoff_cnt)
1848 *cutoff_cnt = reccnt - 1;
1849 if (lastrec) {
1850 if (get_sha1_hex(lastrec, logged_sha1))
1851 die("Log %s is corrupt.", logfile);
1852 if (get_sha1_hex(rec + 41, sha1))
1853 die("Log %s is corrupt.", logfile);
1854 if (hashcmp(logged_sha1, sha1)) {
1855 warning("Log %s has gap after %s.",
1856 logfile, show_date(date, tz, DATE_RFC2822));
1859 else if (date == at_time) {
1860 if (get_sha1_hex(rec + 41, sha1))
1861 die("Log %s is corrupt.", logfile);
1863 else {
1864 if (get_sha1_hex(rec + 41, logged_sha1))
1865 die("Log %s is corrupt.", logfile);
1866 if (hashcmp(logged_sha1, sha1)) {
1867 warning("Log %s unexpectedly ended on %s.",
1868 logfile, show_date(date, tz, DATE_RFC2822));
1871 munmap(log_mapped, mapsz);
1872 return 0;
1874 lastrec = rec;
1875 if (cnt > 0)
1876 cnt--;
1879 rec = logdata;
1880 while (rec < logend && *rec != '>' && *rec != '\n')
1881 rec++;
1882 if (rec == logend || *rec == '\n')
1883 die("Log %s is corrupt.", logfile);
1884 date = strtoul(rec + 1, &tz_c, 10);
1885 tz = strtoul(tz_c, NULL, 10);
1886 if (get_sha1_hex(logdata, sha1))
1887 die("Log %s is corrupt.", logfile);
1888 if (is_null_sha1(sha1)) {
1889 if (get_sha1_hex(logdata + 41, sha1))
1890 die("Log %s is corrupt.", logfile);
1892 if (msg)
1893 *msg = ref_msg(logdata, logend);
1894 munmap(log_mapped, mapsz);
1896 if (cutoff_time)
1897 *cutoff_time = date;
1898 if (cutoff_tz)
1899 *cutoff_tz = tz;
1900 if (cutoff_cnt)
1901 *cutoff_cnt = reccnt;
1902 return 1;
1905 int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
1907 const char *logfile;
1908 FILE *logfp;
1909 struct strbuf sb = STRBUF_INIT;
1910 int ret = 0;
1912 logfile = git_path("logs/%s", refname);
1913 logfp = fopen(logfile, "r");
1914 if (!logfp)
1915 return -1;
1917 if (ofs) {
1918 struct stat statbuf;
1919 if (fstat(fileno(logfp), &statbuf) ||
1920 statbuf.st_size < ofs ||
1921 fseek(logfp, -ofs, SEEK_END) ||
1922 strbuf_getwholeline(&sb, logfp, '\n')) {
1923 fclose(logfp);
1924 strbuf_release(&sb);
1925 return -1;
1929 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1930 unsigned char osha1[20], nsha1[20];
1931 char *email_end, *message;
1932 unsigned long timestamp;
1933 int tz;
1935 /* old SP new SP name <email> SP time TAB msg LF */
1936 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1937 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1938 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1939 !(email_end = strchr(sb.buf + 82, '>')) ||
1940 email_end[1] != ' ' ||
1941 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1942 !message || message[0] != ' ' ||
1943 (message[1] != '+' && message[1] != '-') ||
1944 !isdigit(message[2]) || !isdigit(message[3]) ||
1945 !isdigit(message[4]) || !isdigit(message[5]))
1946 continue; /* corrupt? */
1947 email_end[1] = '\0';
1948 tz = strtol(message + 1, NULL, 10);
1949 if (message[6] != '\t')
1950 message += 6;
1951 else
1952 message += 7;
1953 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1954 cb_data);
1955 if (ret)
1956 break;
1958 fclose(logfp);
1959 strbuf_release(&sb);
1960 return ret;
1963 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
1965 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
1968 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1970 DIR *dir = opendir(git_path("logs/%s", base));
1971 int retval = 0;
1973 if (dir) {
1974 struct dirent *de;
1975 int baselen = strlen(base);
1976 char *log = xmalloc(baselen + 257);
1978 memcpy(log, base, baselen);
1979 if (baselen && base[baselen-1] != '/')
1980 log[baselen++] = '/';
1982 while ((de = readdir(dir)) != NULL) {
1983 struct stat st;
1984 int namelen;
1986 if (de->d_name[0] == '.')
1987 continue;
1988 namelen = strlen(de->d_name);
1989 if (namelen > 255)
1990 continue;
1991 if (has_extension(de->d_name, ".lock"))
1992 continue;
1993 memcpy(log + baselen, de->d_name, namelen+1);
1994 if (stat(git_path("logs/%s", log), &st) < 0)
1995 continue;
1996 if (S_ISDIR(st.st_mode)) {
1997 retval = do_for_each_reflog(log, fn, cb_data);
1998 } else {
1999 unsigned char sha1[20];
2000 if (!resolve_ref(log, sha1, 0, NULL))
2001 retval = error("bad ref for %s", log);
2002 else
2003 retval = fn(log, sha1, 0, cb_data);
2005 if (retval)
2006 break;
2008 free(log);
2009 closedir(dir);
2011 else if (*base)
2012 return errno;
2013 return retval;
2016 int for_each_reflog(each_ref_fn fn, void *cb_data)
2018 return do_for_each_reflog("", fn, cb_data);
2021 int update_ref(const char *action, const char *refname,
2022 const unsigned char *sha1, const unsigned char *oldval,
2023 int flags, enum action_on_err onerr)
2025 static struct ref_lock *lock;
2026 lock = lock_any_ref_for_update(refname, oldval, flags);
2027 if (!lock) {
2028 const char *str = "Cannot lock the ref '%s'.";
2029 switch (onerr) {
2030 case MSG_ON_ERR: error(str, refname); break;
2031 case DIE_ON_ERR: die(str, refname); break;
2032 case QUIET_ON_ERR: break;
2034 return 1;
2036 if (write_ref_sha1(lock, sha1, action) < 0) {
2037 const char *str = "Cannot update the ref '%s'.";
2038 switch (onerr) {
2039 case MSG_ON_ERR: error(str, refname); break;
2040 case DIE_ON_ERR: die(str, refname); break;
2041 case QUIET_ON_ERR: break;
2043 return 1;
2045 return 0;
2048 int ref_exists(const char *refname)
2050 unsigned char sha1[20];
2051 return !!resolve_ref(refname, sha1, 1, NULL);
2054 struct ref *find_ref_by_name(const struct ref *list, const char *name)
2056 for ( ; list; list = list->next)
2057 if (!strcmp(list->name, name))
2058 return (struct ref *)list;
2059 return NULL;
2063 * generate a format suitable for scanf from a ref_rev_parse_rules
2064 * rule, that is replace the "%.*s" spec with a "%s" spec
2066 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2068 char *spec;
2070 spec = strstr(rule, "%.*s");
2071 if (!spec || strstr(spec + 4, "%.*s"))
2072 die("invalid rule in ref_rev_parse_rules: %s", rule);
2074 /* copy all until spec */
2075 strncpy(scanf_fmt, rule, spec - rule);
2076 scanf_fmt[spec - rule] = '\0';
2077 /* copy new spec */
2078 strcat(scanf_fmt, "%s");
2079 /* copy remaining rule */
2080 strcat(scanf_fmt, spec + 4);
2082 return;
2085 char *shorten_unambiguous_ref(const char *refname, int strict)
2087 int i;
2088 static char **scanf_fmts;
2089 static int nr_rules;
2090 char *short_name;
2092 /* pre generate scanf formats from ref_rev_parse_rules[] */
2093 if (!nr_rules) {
2094 size_t total_len = 0;
2096 /* the rule list is NULL terminated, count them first */
2097 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2098 /* no +1 because strlen("%s") < strlen("%.*s") */
2099 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2101 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2103 total_len = 0;
2104 for (i = 0; i < nr_rules; i++) {
2105 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2106 + total_len;
2107 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2108 total_len += strlen(ref_rev_parse_rules[i]);
2112 /* bail out if there are no rules */
2113 if (!nr_rules)
2114 return xstrdup(refname);
2116 /* buffer for scanf result, at most refname must fit */
2117 short_name = xstrdup(refname);
2119 /* skip first rule, it will always match */
2120 for (i = nr_rules - 1; i > 0 ; --i) {
2121 int j;
2122 int rules_to_fail = i;
2123 int short_name_len;
2125 if (1 != sscanf(refname, scanf_fmts[i], short_name))
2126 continue;
2128 short_name_len = strlen(short_name);
2131 * in strict mode, all (except the matched one) rules
2132 * must fail to resolve to a valid non-ambiguous ref
2134 if (strict)
2135 rules_to_fail = nr_rules;
2138 * check if the short name resolves to a valid ref,
2139 * but use only rules prior to the matched one
2141 for (j = 0; j < rules_to_fail; j++) {
2142 const char *rule = ref_rev_parse_rules[j];
2143 unsigned char short_objectname[20];
2144 char refname[PATH_MAX];
2146 /* skip matched rule */
2147 if (i == j)
2148 continue;
2151 * the short name is ambiguous, if it resolves
2152 * (with this previous rule) to a valid ref
2153 * read_ref() returns 0 on success
2155 mksnpath(refname, sizeof(refname),
2156 rule, short_name_len, short_name);
2157 if (!read_ref(refname, short_objectname))
2158 break;
2162 * short name is non-ambiguous if all previous rules
2163 * haven't resolved to a valid ref
2165 if (j == rules_to_fail)
2166 return short_name;
2169 free(short_name);
2170 return xstrdup(refname);