submodule: Use cat instead of echo to avoid DOS line-endings
[git/dscho.git] / refs.c
blob75089598671af76c5efcdefc5e3a93c1cd203d80
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,
61 int check_name)
63 int len;
64 struct ref_entry *ref;
66 if (check_name &&
67 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
68 die("Reference has invalid format: '%s'", refname);
69 len = strlen(refname) + 1;
70 ref = xmalloc(sizeof(struct ref_entry) + len);
71 hashcpy(ref->sha1, sha1);
72 hashclr(ref->peeled);
73 memcpy(ref->name, refname, len);
74 ref->flag = flag;
75 return ref;
78 /* Add a ref_entry to the end of the ref_array (unsorted). */
79 static void add_ref(struct ref_array *refs, struct ref_entry *ref)
81 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
82 refs->refs[refs->nr++] = ref;
85 static int ref_entry_cmp(const void *a, const void *b)
87 struct ref_entry *one = *(struct ref_entry **)a;
88 struct ref_entry *two = *(struct ref_entry **)b;
89 return strcmp(one->name, two->name);
93 * Emit a warning and return true iff ref1 and ref2 have the same name
94 * and the same sha1. Die if they have the same name but different
95 * sha1s.
97 static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
99 if (!strcmp(ref1->name, ref2->name)) {
100 /* Duplicate name; make sure that the SHA1s match: */
101 if (hashcmp(ref1->sha1, ref2->sha1))
102 die("Duplicated ref, and SHA1s don't match: %s",
103 ref1->name);
104 warning("Duplicated ref: %s", ref1->name);
105 return 1;
106 } else {
107 return 0;
111 static void sort_ref_array(struct ref_array *array)
113 int i = 0, j = 1;
115 /* Nothing to sort unless there are at least two entries */
116 if (array->nr < 2)
117 return;
119 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
121 /* Remove any duplicates from the ref_array */
122 for (; j < array->nr; j++) {
123 struct ref_entry *a = array->refs[i];
124 struct ref_entry *b = array->refs[j];
125 if (is_dup_ref(a, b)) {
126 free(b);
127 continue;
129 i++;
130 array->refs[i] = array->refs[j];
132 array->nr = i + 1;
135 static struct ref_entry *search_ref_array(struct ref_array *array, const char *refname)
137 struct ref_entry *e, **r;
138 int len;
140 if (refname == NULL)
141 return NULL;
143 if (!array->nr)
144 return NULL;
146 len = strlen(refname) + 1;
147 e = xmalloc(sizeof(struct ref_entry) + len);
148 memcpy(e->name, refname, len);
150 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
152 free(e);
154 if (r == NULL)
155 return NULL;
157 return *r;
161 * Future: need to be in "struct repository"
162 * when doing a full libification.
164 static struct ref_cache {
165 struct ref_cache *next;
166 char did_loose;
167 char did_packed;
168 struct ref_array loose;
169 struct ref_array packed;
170 /* The submodule name, or "" for the main repo. */
171 char name[FLEX_ARRAY];
172 } *ref_cache;
174 static struct ref_entry *current_ref;
176 static struct ref_array extra_refs;
178 static void clear_ref_array(struct ref_array *array)
180 int i;
181 for (i = 0; i < array->nr; i++)
182 free(array->refs[i]);
183 free(array->refs);
184 array->nr = array->alloc = 0;
185 array->refs = NULL;
188 static void clear_packed_ref_cache(struct ref_cache *refs)
190 if (refs->did_packed)
191 clear_ref_array(&refs->packed);
192 refs->did_packed = 0;
195 static void clear_loose_ref_cache(struct ref_cache *refs)
197 if (refs->did_loose)
198 clear_ref_array(&refs->loose);
199 refs->did_loose = 0;
202 static struct ref_cache *create_ref_cache(const char *submodule)
204 int len;
205 struct ref_cache *refs;
206 if (!submodule)
207 submodule = "";
208 len = strlen(submodule) + 1;
209 refs = xcalloc(1, sizeof(struct ref_cache) + len);
210 memcpy(refs->name, submodule, len);
211 return refs;
215 * Return a pointer to a ref_cache for the specified submodule. For
216 * the main repository, use submodule==NULL. The returned structure
217 * will be allocated and initialized but not necessarily populated; it
218 * should not be freed.
220 static struct ref_cache *get_ref_cache(const char *submodule)
222 struct ref_cache *refs = ref_cache;
223 if (!submodule)
224 submodule = "";
225 while (refs) {
226 if (!strcmp(submodule, refs->name))
227 return refs;
228 refs = refs->next;
231 refs = create_ref_cache(submodule);
232 refs->next = ref_cache;
233 ref_cache = refs;
234 return refs;
237 void invalidate_ref_cache(const char *submodule)
239 struct ref_cache *refs = get_ref_cache(submodule);
240 clear_packed_ref_cache(refs);
241 clear_loose_ref_cache(refs);
244 static void read_packed_refs(FILE *f, struct ref_array *array)
246 struct ref_entry *last = NULL;
247 char refline[PATH_MAX];
248 int flag = REF_ISPACKED;
250 while (fgets(refline, sizeof(refline), f)) {
251 unsigned char sha1[20];
252 const char *refname;
253 static const char header[] = "# pack-refs with:";
255 if (!strncmp(refline, header, sizeof(header)-1)) {
256 const char *traits = refline + sizeof(header) - 1;
257 if (strstr(traits, " peeled "))
258 flag |= REF_KNOWS_PEELED;
259 /* perhaps other traits later as well */
260 continue;
263 refname = parse_ref_line(refline, sha1);
264 if (refname) {
265 last = create_ref_entry(refname, sha1, flag, 1);
266 add_ref(array, last);
267 continue;
269 if (last &&
270 refline[0] == '^' &&
271 strlen(refline) == 42 &&
272 refline[41] == '\n' &&
273 !get_sha1_hex(refline + 1, sha1))
274 hashcpy(last->peeled, sha1);
276 sort_ref_array(array);
279 void add_extra_ref(const char *refname, const unsigned char *sha1, int flag)
281 add_ref(&extra_refs, create_ref_entry(refname, sha1, flag, 0));
284 void clear_extra_refs(void)
286 clear_ref_array(&extra_refs);
289 static struct ref_array *get_packed_refs(struct ref_cache *refs)
291 if (!refs->did_packed) {
292 const char *packed_refs_file;
293 FILE *f;
295 if (*refs->name)
296 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
297 else
298 packed_refs_file = git_path("packed-refs");
299 f = fopen(packed_refs_file, "r");
300 if (f) {
301 read_packed_refs(f, &refs->packed);
302 fclose(f);
304 refs->did_packed = 1;
306 return &refs->packed;
309 static void get_ref_dir(struct ref_cache *refs, const char *base,
310 struct ref_array *array)
312 DIR *dir;
313 const char *path;
315 if (*refs->name)
316 path = git_path_submodule(refs->name, "%s", base);
317 else
318 path = git_path("%s", base);
321 dir = opendir(path);
323 if (dir) {
324 struct dirent *de;
325 int baselen = strlen(base);
326 char *refname = xmalloc(baselen + 257);
328 memcpy(refname, base, baselen);
329 if (baselen && base[baselen-1] != '/')
330 refname[baselen++] = '/';
332 while ((de = readdir(dir)) != NULL) {
333 unsigned char sha1[20];
334 struct stat st;
335 int flag;
336 int namelen;
337 const char *refdir;
339 if (de->d_name[0] == '.')
340 continue;
341 namelen = strlen(de->d_name);
342 if (namelen > 255)
343 continue;
344 if (has_extension(de->d_name, ".lock"))
345 continue;
346 memcpy(refname + baselen, de->d_name, namelen+1);
347 refdir = *refs->name
348 ? git_path_submodule(refs->name, "%s", refname)
349 : git_path("%s", refname);
350 if (stat(refdir, &st) < 0)
351 continue;
352 if (S_ISDIR(st.st_mode)) {
353 get_ref_dir(refs, refname, array);
354 continue;
356 if (*refs->name) {
357 hashclr(sha1);
358 flag = 0;
359 if (resolve_gitlink_ref(refs->name, refname, sha1) < 0) {
360 hashclr(sha1);
361 flag |= REF_ISBROKEN;
363 } else
364 if (read_ref_full(refname, sha1, 1, &flag)) {
365 hashclr(sha1);
366 flag |= REF_ISBROKEN;
368 add_ref(array, create_ref_entry(refname, sha1, flag, 1));
370 free(refname);
371 closedir(dir);
375 struct warn_if_dangling_data {
376 FILE *fp;
377 const char *refname;
378 const char *msg_fmt;
381 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
382 int flags, void *cb_data)
384 struct warn_if_dangling_data *d = cb_data;
385 const char *resolves_to;
386 unsigned char junk[20];
388 if (!(flags & REF_ISSYMREF))
389 return 0;
391 resolves_to = resolve_ref(refname, junk, 0, NULL);
392 if (!resolves_to || strcmp(resolves_to, d->refname))
393 return 0;
395 fprintf(d->fp, d->msg_fmt, refname);
396 return 0;
399 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
401 struct warn_if_dangling_data data;
403 data.fp = fp;
404 data.refname = refname;
405 data.msg_fmt = msg_fmt;
406 for_each_rawref(warn_if_dangling_symref, &data);
409 static struct ref_array *get_loose_refs(struct ref_cache *refs)
411 if (!refs->did_loose) {
412 get_ref_dir(refs, "refs", &refs->loose);
413 sort_ref_array(&refs->loose);
414 refs->did_loose = 1;
416 return &refs->loose;
419 /* We allow "recursive" symbolic refs. Only within reason, though */
420 #define MAXDEPTH 5
421 #define MAXREFLEN (1024)
423 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
424 const char *refname, unsigned char *sha1)
426 int retval = -1;
427 struct ref_entry *ref;
428 struct ref_array *array = get_packed_refs(refs);
430 ref = search_ref_array(array, refname);
431 if (ref != NULL) {
432 memcpy(sha1, ref->sha1, 20);
433 retval = 0;
435 return retval;
438 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
439 const char *refname, unsigned char *sha1,
440 int recursion)
442 int fd, len;
443 char buffer[128], *p;
444 char *path;
446 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
447 return -1;
448 path = *refs->name
449 ? git_path_submodule(refs->name, "%s", refname)
450 : git_path("%s", refname);
451 fd = open(path, O_RDONLY);
452 if (fd < 0)
453 return resolve_gitlink_packed_ref(refs, refname, sha1);
455 len = read(fd, buffer, sizeof(buffer)-1);
456 close(fd);
457 if (len < 0)
458 return -1;
459 while (len && isspace(buffer[len-1]))
460 len--;
461 buffer[len] = 0;
463 /* Was it a detached head or an old-fashioned symlink? */
464 if (!get_sha1_hex(buffer, sha1))
465 return 0;
467 /* Symref? */
468 if (strncmp(buffer, "ref:", 4))
469 return -1;
470 p = buffer + 4;
471 while (isspace(*p))
472 p++;
474 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
477 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
479 int len = strlen(path), retval;
480 char *submodule;
481 struct ref_cache *refs;
483 while (len && path[len-1] == '/')
484 len--;
485 if (!len)
486 return -1;
487 submodule = xstrndup(path, len);
488 refs = get_ref_cache(submodule);
489 free(submodule);
491 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
492 return retval;
496 * Try to read ref from the packed references. On success, set sha1
497 * and return 0; otherwise, return -1.
499 static int get_packed_ref(const char *refname, unsigned char *sha1)
501 struct ref_array *packed = get_packed_refs(get_ref_cache(NULL));
502 struct ref_entry *entry = search_ref_array(packed, refname);
503 if (entry) {
504 hashcpy(sha1, entry->sha1);
505 return 0;
507 return -1;
510 const char *resolve_ref(const char *refname, unsigned char *sha1, int reading, int *flag)
512 int depth = MAXDEPTH;
513 ssize_t len;
514 char buffer[256];
515 static char refname_buffer[256];
517 if (flag)
518 *flag = 0;
520 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
521 return NULL;
523 for (;;) {
524 char path[PATH_MAX];
525 struct stat st;
526 char *buf;
527 int fd;
529 if (--depth < 0)
530 return NULL;
532 git_snpath(path, sizeof(path), "%s", refname);
534 if (lstat(path, &st) < 0) {
535 if (errno != ENOENT)
536 return NULL;
538 * The loose reference file does not exist;
539 * check for a packed reference.
541 if (!get_packed_ref(refname, sha1)) {
542 if (flag)
543 *flag |= REF_ISPACKED;
544 return refname;
546 /* The reference is not a packed reference, either. */
547 if (reading) {
548 return NULL;
549 } else {
550 hashclr(sha1);
551 return refname;
555 /* Follow "normalized" - ie "refs/.." symlinks by hand */
556 if (S_ISLNK(st.st_mode)) {
557 len = readlink(path, buffer, sizeof(buffer)-1);
558 if (len < 0)
559 return NULL;
560 buffer[len] = 0;
561 if (!prefixcmp(buffer, "refs/") &&
562 !check_refname_format(buffer, 0)) {
563 strcpy(refname_buffer, buffer);
564 refname = refname_buffer;
565 if (flag)
566 *flag |= REF_ISSYMREF;
567 continue;
571 /* Is it a directory? */
572 if (S_ISDIR(st.st_mode)) {
573 errno = EISDIR;
574 return NULL;
578 * Anything else, just open it and try to use it as
579 * a ref
581 fd = open(path, O_RDONLY);
582 if (fd < 0)
583 return NULL;
584 len = read_in_full(fd, buffer, sizeof(buffer)-1);
585 close(fd);
586 if (len < 0)
587 return NULL;
588 while (len && isspace(buffer[len-1]))
589 len--;
590 buffer[len] = '\0';
593 * Is it a symbolic ref?
595 if (prefixcmp(buffer, "ref:"))
596 break;
597 if (flag)
598 *flag |= REF_ISSYMREF;
599 buf = buffer + 4;
600 while (isspace(*buf))
601 buf++;
602 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
603 if (flag)
604 *flag |= REF_ISBROKEN;
605 return NULL;
607 refname = strcpy(refname_buffer, buf);
609 /* Please note that FETCH_HEAD has a second line containing other data. */
610 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
611 if (flag)
612 *flag |= REF_ISBROKEN;
613 return NULL;
615 return refname;
618 /* The argument to filter_refs */
619 struct ref_filter {
620 const char *pattern;
621 each_ref_fn *fn;
622 void *cb_data;
625 int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
627 if (resolve_ref(refname, sha1, reading, flags))
628 return 0;
629 return -1;
632 int read_ref(const char *ref, unsigned char *sha1)
634 return read_ref_full(ref, sha1, 1, NULL);
637 #define DO_FOR_EACH_INCLUDE_BROKEN 01
638 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
639 int flags, void *cb_data, struct ref_entry *entry)
641 if (prefixcmp(entry->name, base))
642 return 0;
644 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
645 if (entry->flag & REF_ISBROKEN)
646 return 0; /* ignore broken refs e.g. dangling symref */
647 if (!has_sha1_file(entry->sha1)) {
648 error("%s does not point to a valid object!", entry->name);
649 return 0;
652 current_ref = entry;
653 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
656 static int filter_refs(const char *refname, const unsigned char *sha, int flags,
657 void *data)
659 struct ref_filter *filter = (struct ref_filter *)data;
660 if (fnmatch(filter->pattern, refname, 0))
661 return 0;
662 return filter->fn(refname, sha, flags, filter->cb_data);
665 int peel_ref(const char *refname, unsigned char *sha1)
667 int flag;
668 unsigned char base[20];
669 struct object *o;
671 if (current_ref && (current_ref->name == refname
672 || !strcmp(current_ref->name, refname))) {
673 if (current_ref->flag & REF_KNOWS_PEELED) {
674 hashcpy(sha1, current_ref->peeled);
675 return 0;
677 hashcpy(base, current_ref->sha1);
678 goto fallback;
681 if (read_ref_full(refname, base, 1, &flag))
682 return -1;
684 if ((flag & REF_ISPACKED)) {
685 struct ref_array *array = get_packed_refs(get_ref_cache(NULL));
686 struct ref_entry *r = search_ref_array(array, refname);
688 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
689 hashcpy(sha1, r->peeled);
690 return 0;
694 fallback:
695 o = parse_object(base);
696 if (o && o->type == OBJ_TAG) {
697 o = deref_tag(o, refname, 0);
698 if (o) {
699 hashcpy(sha1, o->sha1);
700 return 0;
703 return -1;
706 static int do_for_each_ref_in_array(struct ref_array *array, int offset,
707 const char *base,
708 each_ref_fn fn, int trim, int flags, void *cb_data)
710 int i;
711 for (i = offset; i < array->nr; i++) {
712 int retval = do_one_ref(base, fn, trim, flags, cb_data, array->refs[i]);
713 if (retval)
714 return retval;
716 return 0;
719 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
720 int trim, int flags, void *cb_data)
722 int retval = 0, p = 0, l = 0;
723 struct ref_cache *refs = get_ref_cache(submodule);
724 struct ref_array *packed = get_packed_refs(refs);
725 struct ref_array *loose = get_loose_refs(refs);
727 retval = do_for_each_ref_in_array(&extra_refs, 0,
728 base, fn, trim, flags, cb_data);
729 if (retval)
730 goto end_each;
732 while (p < packed->nr && l < loose->nr) {
733 struct ref_entry *entry;
734 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
735 if (!cmp) {
736 p++;
737 continue;
739 if (cmp > 0) {
740 entry = loose->refs[l++];
741 } else {
742 entry = packed->refs[p++];
744 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
745 if (retval)
746 goto end_each;
749 if (l < loose->nr) {
750 retval = do_for_each_ref_in_array(loose, l,
751 base, fn, trim, flags, cb_data);
752 } else {
753 retval = do_for_each_ref_in_array(packed, p,
754 base, fn, trim, flags, cb_data);
757 end_each:
758 current_ref = NULL;
759 return retval;
763 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
765 unsigned char sha1[20];
766 int flag;
768 if (submodule) {
769 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
770 return fn("HEAD", sha1, 0, cb_data);
772 return 0;
775 if (!read_ref_full("HEAD", sha1, 1, &flag))
776 return fn("HEAD", sha1, flag, cb_data);
778 return 0;
781 int head_ref(each_ref_fn fn, void *cb_data)
783 return do_head_ref(NULL, fn, cb_data);
786 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
788 return do_head_ref(submodule, fn, cb_data);
791 int for_each_ref(each_ref_fn fn, void *cb_data)
793 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
796 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
798 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
801 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
803 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
806 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
807 each_ref_fn fn, void *cb_data)
809 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
812 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
814 return for_each_ref_in("refs/tags/", fn, cb_data);
817 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
819 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
822 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
824 return for_each_ref_in("refs/heads/", fn, cb_data);
827 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
829 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
832 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
834 return for_each_ref_in("refs/remotes/", fn, cb_data);
837 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
839 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
842 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
844 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
847 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
849 struct strbuf buf = STRBUF_INIT;
850 int ret = 0;
851 unsigned char sha1[20];
852 int flag;
854 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
855 if (!read_ref_full(buf.buf, sha1, 1, &flag))
856 ret = fn(buf.buf, sha1, flag, cb_data);
857 strbuf_release(&buf);
859 return ret;
862 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
864 struct strbuf buf = STRBUF_INIT;
865 int ret;
866 strbuf_addf(&buf, "%srefs/", get_git_namespace());
867 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
868 strbuf_release(&buf);
869 return ret;
872 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
873 const char *prefix, void *cb_data)
875 struct strbuf real_pattern = STRBUF_INIT;
876 struct ref_filter filter;
877 int ret;
879 if (!prefix && prefixcmp(pattern, "refs/"))
880 strbuf_addstr(&real_pattern, "refs/");
881 else if (prefix)
882 strbuf_addstr(&real_pattern, prefix);
883 strbuf_addstr(&real_pattern, pattern);
885 if (!has_glob_specials(pattern)) {
886 /* Append implied '/' '*' if not present. */
887 if (real_pattern.buf[real_pattern.len - 1] != '/')
888 strbuf_addch(&real_pattern, '/');
889 /* No need to check for '*', there is none. */
890 strbuf_addch(&real_pattern, '*');
893 filter.pattern = real_pattern.buf;
894 filter.fn = fn;
895 filter.cb_data = cb_data;
896 ret = for_each_ref(filter_refs, &filter);
898 strbuf_release(&real_pattern);
899 return ret;
902 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
904 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
907 int for_each_rawref(each_ref_fn fn, void *cb_data)
909 return do_for_each_ref(NULL, "", fn, 0,
910 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
914 * Make sure "ref" is something reasonable to have under ".git/refs/";
915 * We do not like it if:
917 * - any path component of it begins with ".", or
918 * - it has double dots "..", or
919 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
920 * - it ends with a "/".
921 * - it ends with ".lock"
922 * - it contains a "\" (backslash)
925 /* Return true iff ch is not allowed in reference names. */
926 static inline int bad_ref_char(int ch)
928 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
929 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
930 return 1;
931 /* 2.13 Pattern Matching Notation */
932 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
933 return 1;
934 return 0;
938 * Try to read one refname component from the front of refname. Return
939 * the length of the component found, or -1 if the component is not
940 * legal.
942 static int check_refname_component(const char *refname, int flags)
944 const char *cp;
945 char last = '\0';
947 for (cp = refname; ; cp++) {
948 char ch = *cp;
949 if (ch == '\0' || ch == '/')
950 break;
951 if (bad_ref_char(ch))
952 return -1; /* Illegal character in refname. */
953 if (last == '.' && ch == '.')
954 return -1; /* Refname contains "..". */
955 if (last == '@' && ch == '{')
956 return -1; /* Refname contains "@{". */
957 last = ch;
959 if (cp == refname)
960 return -1; /* Component has zero length. */
961 if (refname[0] == '.') {
962 if (!(flags & REFNAME_DOT_COMPONENT))
963 return -1; /* Component starts with '.'. */
965 * Even if leading dots are allowed, don't allow "."
966 * as a component (".." is prevented by a rule above).
968 if (refname[1] == '\0')
969 return -1; /* Component equals ".". */
971 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
972 return -1; /* Refname ends with ".lock". */
973 return cp - refname;
976 int check_refname_format(const char *refname, int flags)
978 int component_len, component_count = 0;
980 while (1) {
981 /* We are at the start of a path component. */
982 component_len = check_refname_component(refname, flags);
983 if (component_len < 0) {
984 if ((flags & REFNAME_REFSPEC_PATTERN) &&
985 refname[0] == '*' &&
986 (refname[1] == '\0' || refname[1] == '/')) {
987 /* Accept one wildcard as a full refname component. */
988 flags &= ~REFNAME_REFSPEC_PATTERN;
989 component_len = 1;
990 } else {
991 return -1;
994 component_count++;
995 if (refname[component_len] == '\0')
996 break;
997 /* Skip to next component. */
998 refname += component_len + 1;
1001 if (refname[component_len - 1] == '.')
1002 return -1; /* Refname ends with '.'. */
1003 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
1004 return -1; /* Refname has only one component. */
1005 return 0;
1008 const char *prettify_refname(const char *name)
1010 return name + (
1011 !prefixcmp(name, "refs/heads/") ? 11 :
1012 !prefixcmp(name, "refs/tags/") ? 10 :
1013 !prefixcmp(name, "refs/remotes/") ? 13 :
1017 const char *ref_rev_parse_rules[] = {
1018 "%.*s",
1019 "refs/%.*s",
1020 "refs/tags/%.*s",
1021 "refs/heads/%.*s",
1022 "refs/remotes/%.*s",
1023 "refs/remotes/%.*s/HEAD",
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 (read_ref_full(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 (!read_ref_full(newrefname, sha1, 1, &flag) &&
1447 delete_ref(newrefname, sha1, REF_NODEREF)) {
1448 if (errno==EISDIR) {
1449 if (remove_empty_directories(git_path("%s", newrefname))) {
1450 error("Directory not empty: %s", newrefname);
1451 goto rollback;
1453 } else {
1454 error("unable to delete existing %s", newrefname);
1455 goto rollback;
1459 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1460 error("unable to create directory for %s", newrefname);
1461 goto rollback;
1464 retry:
1465 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
1466 if (errno==EISDIR || errno==ENOTDIR) {
1468 * rename(a, b) when b is an existing
1469 * directory ought to result in ISDIR, but
1470 * Solaris 5.8 gives ENOTDIR. Sheesh.
1472 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1473 error("Directory not empty: logs/%s", newrefname);
1474 goto rollback;
1476 goto retry;
1477 } else {
1478 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1479 newrefname, strerror(errno));
1480 goto rollback;
1483 logmoved = log;
1485 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
1486 if (!lock) {
1487 error("unable to lock %s for update", newrefname);
1488 goto rollback;
1490 lock->force_write = 1;
1491 hashcpy(lock->old_sha1, orig_sha1);
1492 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1493 error("unable to write current sha1 into %s", newrefname);
1494 goto rollback;
1497 return 0;
1499 rollback:
1500 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
1501 if (!lock) {
1502 error("unable to lock %s for rollback", oldrefname);
1503 goto rollbacklog;
1506 lock->force_write = 1;
1507 flag = log_all_ref_updates;
1508 log_all_ref_updates = 0;
1509 if (write_ref_sha1(lock, orig_sha1, NULL))
1510 error("unable to write current sha1 into %s", oldrefname);
1511 log_all_ref_updates = flag;
1513 rollbacklog:
1514 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
1515 error("unable to restore logfile %s from %s: %s",
1516 oldrefname, newrefname, strerror(errno));
1517 if (!logmoved && log &&
1518 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
1519 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1520 oldrefname, strerror(errno));
1522 return 1;
1525 int close_ref(struct ref_lock *lock)
1527 if (close_lock_file(lock->lk))
1528 return -1;
1529 lock->lock_fd = -1;
1530 return 0;
1533 int commit_ref(struct ref_lock *lock)
1535 if (commit_lock_file(lock->lk))
1536 return -1;
1537 lock->lock_fd = -1;
1538 return 0;
1541 void unlock_ref(struct ref_lock *lock)
1543 /* Do not free lock->lk -- atexit() still looks at them */
1544 if (lock->lk)
1545 rollback_lock_file(lock->lk);
1546 free(lock->ref_name);
1547 free(lock->orig_ref_name);
1548 free(lock);
1552 * copy the reflog message msg to buf, which has been allocated sufficiently
1553 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1554 * because reflog file is one line per entry.
1556 static int copy_msg(char *buf, const char *msg)
1558 char *cp = buf;
1559 char c;
1560 int wasspace = 1;
1562 *cp++ = '\t';
1563 while ((c = *msg++)) {
1564 if (wasspace && isspace(c))
1565 continue;
1566 wasspace = isspace(c);
1567 if (wasspace)
1568 c = ' ';
1569 *cp++ = c;
1571 while (buf < cp && isspace(cp[-1]))
1572 cp--;
1573 *cp++ = '\n';
1574 return cp - buf;
1577 int log_ref_setup(const char *refname, char *logfile, int bufsize)
1579 int logfd, oflags = O_APPEND | O_WRONLY;
1581 git_snpath(logfile, bufsize, "logs/%s", refname);
1582 if (log_all_ref_updates &&
1583 (!prefixcmp(refname, "refs/heads/") ||
1584 !prefixcmp(refname, "refs/remotes/") ||
1585 !prefixcmp(refname, "refs/notes/") ||
1586 !strcmp(refname, "HEAD"))) {
1587 if (safe_create_leading_directories(logfile) < 0)
1588 return error("unable to create directory for %s",
1589 logfile);
1590 oflags |= O_CREAT;
1593 logfd = open(logfile, oflags, 0666);
1594 if (logfd < 0) {
1595 if (!(oflags & O_CREAT) && errno == ENOENT)
1596 return 0;
1598 if ((oflags & O_CREAT) && errno == EISDIR) {
1599 if (remove_empty_directories(logfile)) {
1600 return error("There are still logs under '%s'",
1601 logfile);
1603 logfd = open(logfile, oflags, 0666);
1606 if (logfd < 0)
1607 return error("Unable to append to %s: %s",
1608 logfile, strerror(errno));
1611 adjust_shared_perm(logfile);
1612 close(logfd);
1613 return 0;
1616 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
1617 const unsigned char *new_sha1, const char *msg)
1619 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1620 unsigned maxlen, len;
1621 int msglen;
1622 char log_file[PATH_MAX];
1623 char *logrec;
1624 const char *committer;
1626 if (log_all_ref_updates < 0)
1627 log_all_ref_updates = !is_bare_repository();
1629 result = log_ref_setup(refname, log_file, sizeof(log_file));
1630 if (result)
1631 return result;
1633 logfd = open(log_file, oflags);
1634 if (logfd < 0)
1635 return 0;
1636 msglen = msg ? strlen(msg) : 0;
1637 committer = git_committer_info(0);
1638 maxlen = strlen(committer) + msglen + 100;
1639 logrec = xmalloc(maxlen);
1640 len = sprintf(logrec, "%s %s %s\n",
1641 sha1_to_hex(old_sha1),
1642 sha1_to_hex(new_sha1),
1643 committer);
1644 if (msglen)
1645 len += copy_msg(logrec + len - 1, msg) - 1;
1646 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1647 free(logrec);
1648 if (close(logfd) != 0 || written != len)
1649 return error("Unable to append to %s", log_file);
1650 return 0;
1653 static int is_branch(const char *refname)
1655 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1658 int write_ref_sha1(struct ref_lock *lock,
1659 const unsigned char *sha1, const char *logmsg)
1661 static char term = '\n';
1662 struct object *o;
1664 if (!lock)
1665 return -1;
1666 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1667 unlock_ref(lock);
1668 return 0;
1670 o = parse_object(sha1);
1671 if (!o) {
1672 error("Trying to write ref %s with nonexistent object %s",
1673 lock->ref_name, sha1_to_hex(sha1));
1674 unlock_ref(lock);
1675 return -1;
1677 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1678 error("Trying to write non-commit object %s to branch %s",
1679 sha1_to_hex(sha1), lock->ref_name);
1680 unlock_ref(lock);
1681 return -1;
1683 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1684 write_in_full(lock->lock_fd, &term, 1) != 1
1685 || close_ref(lock) < 0) {
1686 error("Couldn't write %s", lock->lk->filename);
1687 unlock_ref(lock);
1688 return -1;
1690 clear_loose_ref_cache(get_ref_cache(NULL));
1691 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1692 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1693 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1694 unlock_ref(lock);
1695 return -1;
1697 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1699 * Special hack: If a branch is updated directly and HEAD
1700 * points to it (may happen on the remote side of a push
1701 * for example) then logically the HEAD reflog should be
1702 * updated too.
1703 * A generic solution implies reverse symref information,
1704 * but finding all symrefs pointing to the given branch
1705 * would be rather costly for this rare event (the direct
1706 * update of a branch) to be worth it. So let's cheat and
1707 * check with HEAD only which should cover 99% of all usage
1708 * scenarios (even 100% of the default ones).
1710 unsigned char head_sha1[20];
1711 int head_flag;
1712 const char *head_ref;
1713 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1714 if (head_ref && (head_flag & REF_ISSYMREF) &&
1715 !strcmp(head_ref, lock->ref_name))
1716 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1718 if (commit_ref(lock)) {
1719 error("Couldn't set %s", lock->ref_name);
1720 unlock_ref(lock);
1721 return -1;
1723 unlock_ref(lock);
1724 return 0;
1727 int create_symref(const char *ref_target, const char *refs_heads_master,
1728 const char *logmsg)
1730 const char *lockpath;
1731 char ref[1000];
1732 int fd, len, written;
1733 char *git_HEAD = git_pathdup("%s", ref_target);
1734 unsigned char old_sha1[20], new_sha1[20];
1736 if (logmsg && read_ref(ref_target, old_sha1))
1737 hashclr(old_sha1);
1739 if (safe_create_leading_directories(git_HEAD) < 0)
1740 return error("unable to create directory for %s", git_HEAD);
1742 #ifndef NO_SYMLINK_HEAD
1743 if (prefer_symlink_refs) {
1744 unlink(git_HEAD);
1745 if (!symlink(refs_heads_master, git_HEAD))
1746 goto done;
1747 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1749 #endif
1751 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1752 if (sizeof(ref) <= len) {
1753 error("refname too long: %s", refs_heads_master);
1754 goto error_free_return;
1756 lockpath = mkpath("%s.lock", git_HEAD);
1757 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1758 if (fd < 0) {
1759 error("Unable to open %s for writing", lockpath);
1760 goto error_free_return;
1762 written = write_in_full(fd, ref, len);
1763 if (close(fd) != 0 || written != len) {
1764 error("Unable to write to %s", lockpath);
1765 goto error_unlink_return;
1767 if (rename(lockpath, git_HEAD) < 0) {
1768 error("Unable to create %s", git_HEAD);
1769 goto error_unlink_return;
1771 if (adjust_shared_perm(git_HEAD)) {
1772 error("Unable to fix permissions on %s", lockpath);
1773 error_unlink_return:
1774 unlink_or_warn(lockpath);
1775 error_free_return:
1776 free(git_HEAD);
1777 return -1;
1780 #ifndef NO_SYMLINK_HEAD
1781 done:
1782 #endif
1783 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1784 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1786 free(git_HEAD);
1787 return 0;
1790 static char *ref_msg(const char *line, const char *endp)
1792 const char *ep;
1793 line += 82;
1794 ep = memchr(line, '\n', endp - line);
1795 if (!ep)
1796 ep = endp;
1797 return xmemdupz(line, ep - line);
1800 int read_ref_at(const char *refname, unsigned long at_time, int cnt,
1801 unsigned char *sha1, char **msg,
1802 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1804 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1805 char *tz_c;
1806 int logfd, tz, reccnt = 0;
1807 struct stat st;
1808 unsigned long date;
1809 unsigned char logged_sha1[20];
1810 void *log_mapped;
1811 size_t mapsz;
1813 logfile = git_path("logs/%s", refname);
1814 logfd = open(logfile, O_RDONLY, 0);
1815 if (logfd < 0)
1816 die_errno("Unable to read log '%s'", logfile);
1817 fstat(logfd, &st);
1818 if (!st.st_size)
1819 die("Log %s is empty.", logfile);
1820 mapsz = xsize_t(st.st_size);
1821 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1822 logdata = log_mapped;
1823 close(logfd);
1825 lastrec = NULL;
1826 rec = logend = logdata + st.st_size;
1827 while (logdata < rec) {
1828 reccnt++;
1829 if (logdata < rec && *(rec-1) == '\n')
1830 rec--;
1831 lastgt = NULL;
1832 while (logdata < rec && *(rec-1) != '\n') {
1833 rec--;
1834 if (*rec == '>')
1835 lastgt = rec;
1837 if (!lastgt)
1838 die("Log %s is corrupt.", logfile);
1839 date = strtoul(lastgt + 1, &tz_c, 10);
1840 if (date <= at_time || cnt == 0) {
1841 tz = strtoul(tz_c, NULL, 10);
1842 if (msg)
1843 *msg = ref_msg(rec, logend);
1844 if (cutoff_time)
1845 *cutoff_time = date;
1846 if (cutoff_tz)
1847 *cutoff_tz = tz;
1848 if (cutoff_cnt)
1849 *cutoff_cnt = reccnt - 1;
1850 if (lastrec) {
1851 if (get_sha1_hex(lastrec, logged_sha1))
1852 die("Log %s is corrupt.", logfile);
1853 if (get_sha1_hex(rec + 41, sha1))
1854 die("Log %s is corrupt.", logfile);
1855 if (hashcmp(logged_sha1, sha1)) {
1856 warning("Log %s has gap after %s.",
1857 logfile, show_date(date, tz, DATE_RFC2822));
1860 else if (date == at_time) {
1861 if (get_sha1_hex(rec + 41, sha1))
1862 die("Log %s is corrupt.", logfile);
1864 else {
1865 if (get_sha1_hex(rec + 41, logged_sha1))
1866 die("Log %s is corrupt.", logfile);
1867 if (hashcmp(logged_sha1, sha1)) {
1868 warning("Log %s unexpectedly ended on %s.",
1869 logfile, show_date(date, tz, DATE_RFC2822));
1872 munmap(log_mapped, mapsz);
1873 return 0;
1875 lastrec = rec;
1876 if (cnt > 0)
1877 cnt--;
1880 rec = logdata;
1881 while (rec < logend && *rec != '>' && *rec != '\n')
1882 rec++;
1883 if (rec == logend || *rec == '\n')
1884 die("Log %s is corrupt.", logfile);
1885 date = strtoul(rec + 1, &tz_c, 10);
1886 tz = strtoul(tz_c, NULL, 10);
1887 if (get_sha1_hex(logdata, sha1))
1888 die("Log %s is corrupt.", logfile);
1889 if (is_null_sha1(sha1)) {
1890 if (get_sha1_hex(logdata + 41, sha1))
1891 die("Log %s is corrupt.", logfile);
1893 if (msg)
1894 *msg = ref_msg(logdata, logend);
1895 munmap(log_mapped, mapsz);
1897 if (cutoff_time)
1898 *cutoff_time = date;
1899 if (cutoff_tz)
1900 *cutoff_tz = tz;
1901 if (cutoff_cnt)
1902 *cutoff_cnt = reccnt;
1903 return 1;
1906 int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
1908 const char *logfile;
1909 FILE *logfp;
1910 struct strbuf sb = STRBUF_INIT;
1911 int ret = 0;
1913 logfile = git_path("logs/%s", refname);
1914 logfp = fopen(logfile, "r");
1915 if (!logfp)
1916 return -1;
1918 if (ofs) {
1919 struct stat statbuf;
1920 if (fstat(fileno(logfp), &statbuf) ||
1921 statbuf.st_size < ofs ||
1922 fseek(logfp, -ofs, SEEK_END) ||
1923 strbuf_getwholeline(&sb, logfp, '\n')) {
1924 fclose(logfp);
1925 strbuf_release(&sb);
1926 return -1;
1930 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1931 unsigned char osha1[20], nsha1[20];
1932 char *email_end, *message;
1933 unsigned long timestamp;
1934 int tz;
1936 /* old SP new SP name <email> SP time TAB msg LF */
1937 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1938 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1939 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1940 !(email_end = strchr(sb.buf + 82, '>')) ||
1941 email_end[1] != ' ' ||
1942 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1943 !message || message[0] != ' ' ||
1944 (message[1] != '+' && message[1] != '-') ||
1945 !isdigit(message[2]) || !isdigit(message[3]) ||
1946 !isdigit(message[4]) || !isdigit(message[5]))
1947 continue; /* corrupt? */
1948 email_end[1] = '\0';
1949 tz = strtol(message + 1, NULL, 10);
1950 if (message[6] != '\t')
1951 message += 6;
1952 else
1953 message += 7;
1954 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1955 cb_data);
1956 if (ret)
1957 break;
1959 fclose(logfp);
1960 strbuf_release(&sb);
1961 return ret;
1964 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
1966 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
1969 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1971 DIR *dir = opendir(git_path("logs/%s", base));
1972 int retval = 0;
1974 if (dir) {
1975 struct dirent *de;
1976 int baselen = strlen(base);
1977 char *log = xmalloc(baselen + 257);
1979 memcpy(log, base, baselen);
1980 if (baselen && base[baselen-1] != '/')
1981 log[baselen++] = '/';
1983 while ((de = readdir(dir)) != NULL) {
1984 struct stat st;
1985 int namelen;
1987 if (de->d_name[0] == '.')
1988 continue;
1989 namelen = strlen(de->d_name);
1990 if (namelen > 255)
1991 continue;
1992 if (has_extension(de->d_name, ".lock"))
1993 continue;
1994 memcpy(log + baselen, de->d_name, namelen+1);
1995 if (stat(git_path("logs/%s", log), &st) < 0)
1996 continue;
1997 if (S_ISDIR(st.st_mode)) {
1998 retval = do_for_each_reflog(log, fn, cb_data);
1999 } else {
2000 unsigned char sha1[20];
2001 if (read_ref_full(log, sha1, 0, NULL))
2002 retval = error("bad ref for %s", log);
2003 else
2004 retval = fn(log, sha1, 0, cb_data);
2006 if (retval)
2007 break;
2009 free(log);
2010 closedir(dir);
2012 else if (*base)
2013 return errno;
2014 return retval;
2017 int for_each_reflog(each_ref_fn fn, void *cb_data)
2019 return do_for_each_reflog("", fn, cb_data);
2022 int update_ref(const char *action, const char *refname,
2023 const unsigned char *sha1, const unsigned char *oldval,
2024 int flags, enum action_on_err onerr)
2026 static struct ref_lock *lock;
2027 lock = lock_any_ref_for_update(refname, oldval, flags);
2028 if (!lock) {
2029 const char *str = "Cannot lock the ref '%s'.";
2030 switch (onerr) {
2031 case MSG_ON_ERR: error(str, refname); break;
2032 case DIE_ON_ERR: die(str, refname); break;
2033 case QUIET_ON_ERR: break;
2035 return 1;
2037 if (write_ref_sha1(lock, sha1, action) < 0) {
2038 const char *str = "Cannot update the ref '%s'.";
2039 switch (onerr) {
2040 case MSG_ON_ERR: error(str, refname); break;
2041 case DIE_ON_ERR: die(str, refname); break;
2042 case QUIET_ON_ERR: break;
2044 return 1;
2046 return 0;
2049 int ref_exists(const char *refname)
2051 unsigned char sha1[20];
2052 return !!resolve_ref(refname, sha1, 1, NULL);
2055 struct ref *find_ref_by_name(const struct ref *list, const char *name)
2057 for ( ; list; list = list->next)
2058 if (!strcmp(list->name, name))
2059 return (struct ref *)list;
2060 return NULL;
2064 * generate a format suitable for scanf from a ref_rev_parse_rules
2065 * rule, that is replace the "%.*s" spec with a "%s" spec
2067 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2069 char *spec;
2071 spec = strstr(rule, "%.*s");
2072 if (!spec || strstr(spec + 4, "%.*s"))
2073 die("invalid rule in ref_rev_parse_rules: %s", rule);
2075 /* copy all until spec */
2076 strncpy(scanf_fmt, rule, spec - rule);
2077 scanf_fmt[spec - rule] = '\0';
2078 /* copy new spec */
2079 strcat(scanf_fmt, "%s");
2080 /* copy remaining rule */
2081 strcat(scanf_fmt, spec + 4);
2083 return;
2086 char *shorten_unambiguous_ref(const char *refname, int strict)
2088 int i;
2089 static char **scanf_fmts;
2090 static int nr_rules;
2091 char *short_name;
2093 /* pre generate scanf formats from ref_rev_parse_rules[] */
2094 if (!nr_rules) {
2095 size_t total_len = 0;
2097 /* the rule list is NULL terminated, count them first */
2098 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2099 /* no +1 because strlen("%s") < strlen("%.*s") */
2100 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2102 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2104 total_len = 0;
2105 for (i = 0; i < nr_rules; i++) {
2106 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2107 + total_len;
2108 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2109 total_len += strlen(ref_rev_parse_rules[i]);
2113 /* bail out if there are no rules */
2114 if (!nr_rules)
2115 return xstrdup(refname);
2117 /* buffer for scanf result, at most refname must fit */
2118 short_name = xstrdup(refname);
2120 /* skip first rule, it will always match */
2121 for (i = nr_rules - 1; i > 0 ; --i) {
2122 int j;
2123 int rules_to_fail = i;
2124 int short_name_len;
2126 if (1 != sscanf(refname, scanf_fmts[i], short_name))
2127 continue;
2129 short_name_len = strlen(short_name);
2132 * in strict mode, all (except the matched one) rules
2133 * must fail to resolve to a valid non-ambiguous ref
2135 if (strict)
2136 rules_to_fail = nr_rules;
2139 * check if the short name resolves to a valid ref,
2140 * but use only rules prior to the matched one
2142 for (j = 0; j < rules_to_fail; j++) {
2143 const char *rule = ref_rev_parse_rules[j];
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 (ref_exists(refname))
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);