submodule: Use cat instead of echo to avoid DOS line-endings
[git/dscho.git] / refs.c
blobd3e405631168e6e157a4c15dc17262864cff35bd
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
9 #define REF_BROKEN 010
11 struct ref_entry {
12 unsigned char flag; /* ISSYMREF? ISPACKED? */
13 unsigned char sha1[20];
14 unsigned char peeled[20];
15 char name[FLEX_ARRAY];
18 struct ref_array {
19 int nr, alloc;
20 struct ref_entry **refs;
23 static const char *parse_ref_line(char *line, unsigned char *sha1)
26 * 42: the answer to everything.
28 * In this case, it happens to be the answer to
29 * 40 (length of sha1 hex representation)
30 * +1 (space in between hex and name)
31 * +1 (newline at the end of the line)
33 int len = strlen(line) - 42;
35 if (len <= 0)
36 return NULL;
37 if (get_sha1_hex(line, sha1) < 0)
38 return NULL;
39 if (!isspace(line[40]))
40 return NULL;
41 line += 41;
42 if (isspace(*line))
43 return NULL;
44 if (line[len] != '\n')
45 return NULL;
46 line[len] = 0;
48 return line;
51 static void add_ref(const char *name, const unsigned char *sha1,
52 int flag, struct ref_array *refs,
53 struct ref_entry **new_entry)
55 int len;
56 struct ref_entry *entry;
58 /* Allocate it and add it in.. */
59 len = strlen(name) + 1;
60 entry = xmalloc(sizeof(struct ref_entry) + len);
61 hashcpy(entry->sha1, sha1);
62 hashclr(entry->peeled);
63 if (check_refname_format(name, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
64 die("Reference has invalid format: '%s'", name);
65 memcpy(entry->name, name, len);
66 entry->flag = flag;
67 if (new_entry)
68 *new_entry = entry;
69 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
70 refs->refs[refs->nr++] = entry;
73 static int ref_entry_cmp(const void *a, const void *b)
75 struct ref_entry *one = *(struct ref_entry **)a;
76 struct ref_entry *two = *(struct ref_entry **)b;
77 return strcmp(one->name, two->name);
80 static void sort_ref_array(struct ref_array *array)
82 int i = 0, j = 1;
84 /* Nothing to sort unless there are at least two entries */
85 if (array->nr < 2)
86 return;
88 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
90 /* Remove any duplicates from the ref_array */
91 for (; j < array->nr; j++) {
92 struct ref_entry *a = array->refs[i];
93 struct ref_entry *b = array->refs[j];
94 if (!strcmp(a->name, b->name)) {
95 if (hashcmp(a->sha1, b->sha1))
96 die("Duplicated ref, and SHA1s don't match: %s",
97 a->name);
98 warning("Duplicated ref: %s", a->name);
99 continue;
101 i++;
102 array->refs[i] = array->refs[j];
104 array->nr = i + 1;
107 static struct ref_entry *search_ref_array(struct ref_array *array, const char *name)
109 struct ref_entry *e, **r;
110 int len;
112 if (name == NULL)
113 return NULL;
115 len = strlen(name) + 1;
116 e = xmalloc(sizeof(struct ref_entry) + len);
117 memcpy(e->name, name, len);
119 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
121 free(e);
123 if (r == NULL)
124 return NULL;
126 return *r;
130 * Future: need to be in "struct repository"
131 * when doing a full libification.
133 static struct cached_refs {
134 struct cached_refs *next;
135 char did_loose;
136 char did_packed;
137 struct ref_array loose;
138 struct ref_array packed;
139 /* The submodule name, or "" for the main repo. */
140 char name[FLEX_ARRAY];
141 } *cached_refs;
143 static struct ref_entry *current_ref;
145 static struct ref_array extra_refs;
147 static void free_ref_array(struct ref_array *array)
149 int i;
150 for (i = 0; i < array->nr; i++)
151 free(array->refs[i]);
152 free(array->refs);
153 array->nr = array->alloc = 0;
154 array->refs = NULL;
157 static void clear_cached_refs(struct cached_refs *ca)
159 if (ca->did_loose)
160 free_ref_array(&ca->loose);
161 if (ca->did_packed)
162 free_ref_array(&ca->packed);
163 ca->did_loose = ca->did_packed = 0;
166 static struct cached_refs *create_cached_refs(const char *submodule)
168 int len;
169 struct cached_refs *refs;
170 if (!submodule)
171 submodule = "";
172 len = strlen(submodule) + 1;
173 refs = xcalloc(1, sizeof(struct cached_refs) + len);
174 memcpy(refs->name, submodule, len);
175 return refs;
179 * Return a pointer to a cached_refs for the specified submodule. For
180 * the main repository, use submodule==NULL. The returned structure
181 * will be allocated and initialized but not necessarily populated; it
182 * should not be freed.
184 static struct cached_refs *get_cached_refs(const char *submodule)
186 struct cached_refs *refs = cached_refs;
187 if (!submodule)
188 submodule = "";
189 while (refs) {
190 if (!strcmp(submodule, refs->name))
191 return refs;
192 refs = refs->next;
195 refs = create_cached_refs(submodule);
196 refs->next = cached_refs;
197 cached_refs = refs;
198 return refs;
201 static void invalidate_cached_refs(void)
203 struct cached_refs *refs = cached_refs;
204 while (refs) {
205 clear_cached_refs(refs);
206 refs = refs->next;
210 static void read_packed_refs(FILE *f, struct ref_array *array)
212 struct ref_entry *last = NULL;
213 char refline[PATH_MAX];
214 int flag = REF_ISPACKED;
216 while (fgets(refline, sizeof(refline), f)) {
217 unsigned char sha1[20];
218 const char *name;
219 static const char header[] = "# pack-refs with:";
221 if (!strncmp(refline, header, sizeof(header)-1)) {
222 const char *traits = refline + sizeof(header) - 1;
223 if (strstr(traits, " peeled "))
224 flag |= REF_KNOWS_PEELED;
225 /* perhaps other traits later as well */
226 continue;
229 name = parse_ref_line(refline, sha1);
230 if (name) {
231 add_ref(name, sha1, flag, array, &last);
232 continue;
234 if (last &&
235 refline[0] == '^' &&
236 strlen(refline) == 42 &&
237 refline[41] == '\n' &&
238 !get_sha1_hex(refline + 1, sha1))
239 hashcpy(last->peeled, sha1);
241 sort_ref_array(array);
244 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
246 add_ref(name, sha1, flag, &extra_refs, NULL);
249 void clear_extra_refs(void)
251 free_ref_array(&extra_refs);
254 static struct ref_array *get_packed_refs(const char *submodule)
256 struct cached_refs *refs = get_cached_refs(submodule);
258 if (!refs->did_packed) {
259 const char *packed_refs_file;
260 FILE *f;
262 if (submodule)
263 packed_refs_file = git_path_submodule(submodule, "packed-refs");
264 else
265 packed_refs_file = git_path("packed-refs");
266 f = fopen(packed_refs_file, "r");
267 if (f) {
268 read_packed_refs(f, &refs->packed);
269 fclose(f);
271 refs->did_packed = 1;
273 return &refs->packed;
276 static void get_ref_dir(const char *submodule, const char *base,
277 struct ref_array *array)
279 DIR *dir;
280 const char *path;
282 if (submodule)
283 path = git_path_submodule(submodule, "%s", base);
284 else
285 path = git_path("%s", base);
288 dir = opendir(path);
290 if (dir) {
291 struct dirent *de;
292 int baselen = strlen(base);
293 char *ref = xmalloc(baselen + 257);
295 memcpy(ref, base, baselen);
296 if (baselen && base[baselen-1] != '/')
297 ref[baselen++] = '/';
299 while ((de = readdir(dir)) != NULL) {
300 unsigned char sha1[20];
301 struct stat st;
302 int flag;
303 int namelen;
304 const char *refdir;
306 if (de->d_name[0] == '.')
307 continue;
308 namelen = strlen(de->d_name);
309 if (namelen > 255)
310 continue;
311 if (has_extension(de->d_name, ".lock"))
312 continue;
313 memcpy(ref + baselen, de->d_name, namelen+1);
314 refdir = submodule
315 ? git_path_submodule(submodule, "%s", ref)
316 : git_path("%s", ref);
317 if (stat(refdir, &st) < 0)
318 continue;
319 if (S_ISDIR(st.st_mode)) {
320 get_ref_dir(submodule, ref, array);
321 continue;
323 if (submodule) {
324 hashclr(sha1);
325 flag = 0;
326 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
327 hashclr(sha1);
328 flag |= REF_BROKEN;
330 } else
331 if (!resolve_ref(ref, sha1, 1, &flag)) {
332 hashclr(sha1);
333 flag |= REF_BROKEN;
335 add_ref(ref, sha1, flag, array, NULL);
337 free(ref);
338 closedir(dir);
340 sort_ref_array(array);
343 struct warn_if_dangling_data {
344 FILE *fp;
345 const char *refname;
346 const char *msg_fmt;
349 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
350 int flags, void *cb_data)
352 struct warn_if_dangling_data *d = cb_data;
353 const char *resolves_to;
354 unsigned char junk[20];
356 if (!(flags & REF_ISSYMREF))
357 return 0;
359 resolves_to = resolve_ref(refname, junk, 0, NULL);
360 if (!resolves_to || strcmp(resolves_to, d->refname))
361 return 0;
363 fprintf(d->fp, d->msg_fmt, refname);
364 return 0;
367 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
369 struct warn_if_dangling_data data;
371 data.fp = fp;
372 data.refname = refname;
373 data.msg_fmt = msg_fmt;
374 for_each_rawref(warn_if_dangling_symref, &data);
377 static struct ref_array *get_loose_refs(const char *submodule)
379 struct cached_refs *refs = get_cached_refs(submodule);
381 if (!refs->did_loose) {
382 get_ref_dir(submodule, "refs", &refs->loose);
383 refs->did_loose = 1;
385 return &refs->loose;
388 /* We allow "recursive" symbolic refs. Only within reason, though */
389 #define MAXDEPTH 5
390 #define MAXREFLEN (1024)
392 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
394 int retval = -1;
395 struct ref_entry *ref;
396 struct ref_array *array = get_packed_refs(name);
398 ref = search_ref_array(array, refname);
399 if (ref != NULL) {
400 memcpy(result, ref->sha1, 20);
401 retval = 0;
403 return retval;
406 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
408 int fd, len = strlen(refname);
409 char buffer[128], *p;
411 if (recursion > MAXDEPTH || len > MAXREFLEN)
412 return -1;
413 memcpy(name + pathlen, refname, len+1);
414 fd = open(name, O_RDONLY);
415 if (fd < 0)
416 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
418 len = read(fd, buffer, sizeof(buffer)-1);
419 close(fd);
420 if (len < 0)
421 return -1;
422 while (len && isspace(buffer[len-1]))
423 len--;
424 buffer[len] = 0;
426 /* Was it a detached head or an old-fashioned symlink? */
427 if (!get_sha1_hex(buffer, result))
428 return 0;
430 /* Symref? */
431 if (strncmp(buffer, "ref:", 4))
432 return -1;
433 p = buffer + 4;
434 while (isspace(*p))
435 p++;
437 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
440 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
442 int len = strlen(path), retval;
443 char *gitdir;
444 const char *tmp;
446 while (len && path[len-1] == '/')
447 len--;
448 if (!len)
449 return -1;
450 gitdir = xmalloc(len + MAXREFLEN + 8);
451 memcpy(gitdir, path, len);
452 memcpy(gitdir + len, "/.git", 6);
453 len += 5;
455 tmp = read_gitfile(gitdir);
456 if (tmp) {
457 free(gitdir);
458 len = strlen(tmp);
459 gitdir = xmalloc(len + MAXREFLEN + 3);
460 memcpy(gitdir, tmp, len);
462 gitdir[len] = '/';
463 gitdir[++len] = '\0';
464 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
465 free(gitdir);
466 return retval;
470 * Try to read ref from the packed references. On success, set sha1
471 * and return 0; otherwise, return -1.
473 static int get_packed_ref(const char *ref, unsigned char *sha1)
475 struct ref_array *packed = get_packed_refs(NULL);
476 struct ref_entry *entry = search_ref_array(packed, ref);
477 if (entry) {
478 hashcpy(sha1, entry->sha1);
479 return 0;
481 return -1;
484 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
486 int depth = MAXDEPTH;
487 ssize_t len;
488 char buffer[256];
489 static char ref_buffer[256];
490 char path[PATH_MAX];
492 if (flag)
493 *flag = 0;
495 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
496 return NULL;
498 for (;;) {
499 struct stat st;
500 char *buf;
501 int fd;
503 if (--depth < 0)
504 return NULL;
506 git_snpath(path, sizeof(path), "%s", ref);
508 if (lstat(path, &st) < 0) {
509 if (errno != ENOENT)
510 return NULL;
512 * The loose reference file does not exist;
513 * check for a packed reference.
515 if (!get_packed_ref(ref, sha1)) {
516 if (flag)
517 *flag |= REF_ISPACKED;
518 return ref;
520 /* The reference is not a packed reference, either. */
521 if (reading) {
522 return NULL;
523 } else {
524 hashclr(sha1);
525 return ref;
529 /* Follow "normalized" - ie "refs/.." symlinks by hand */
530 if (S_ISLNK(st.st_mode)) {
531 len = readlink(path, buffer, sizeof(buffer)-1);
532 if (len < 0)
533 return NULL;
534 buffer[len] = 0;
535 if (!prefixcmp(buffer, "refs/") &&
536 !check_refname_format(buffer, 0)) {
537 strcpy(ref_buffer, buffer);
538 ref = ref_buffer;
539 if (flag)
540 *flag |= REF_ISSYMREF;
541 continue;
545 /* Is it a directory? */
546 if (S_ISDIR(st.st_mode)) {
547 errno = EISDIR;
548 return NULL;
552 * Anything else, just open it and try to use it as
553 * a ref
555 fd = open(path, O_RDONLY);
556 if (fd < 0)
557 return NULL;
558 len = read_in_full(fd, buffer, sizeof(buffer)-1);
559 close(fd);
560 if (len < 0)
561 return NULL;
562 while (len && isspace(buffer[len-1]))
563 len--;
564 buffer[len] = '\0';
567 * Is it a symbolic ref?
569 if (prefixcmp(buffer, "ref:"))
570 break;
571 buf = buffer + 4;
572 while (isspace(*buf))
573 buf++;
574 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
575 warning("symbolic reference in %s is formatted incorrectly",
576 path);
577 return NULL;
579 ref = strcpy(ref_buffer, buf);
580 if (flag)
581 *flag |= REF_ISSYMREF;
583 /* Please note that FETCH_HEAD has a second line containing other data. */
584 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
585 warning("reference in %s is formatted incorrectly", path);
586 return NULL;
588 return ref;
591 /* The argument to filter_refs */
592 struct ref_filter {
593 const char *pattern;
594 each_ref_fn *fn;
595 void *cb_data;
598 int read_ref(const char *ref, unsigned char *sha1)
600 if (resolve_ref(ref, sha1, 1, NULL))
601 return 0;
602 return -1;
605 #define DO_FOR_EACH_INCLUDE_BROKEN 01
606 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
607 int flags, void *cb_data, struct ref_entry *entry)
609 if (prefixcmp(entry->name, base))
610 return 0;
612 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
613 if (entry->flag & REF_BROKEN)
614 return 0; /* ignore dangling symref */
615 if (!has_sha1_file(entry->sha1)) {
616 error("%s does not point to a valid object!", entry->name);
617 return 0;
620 current_ref = entry;
621 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
624 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
625 void *data)
627 struct ref_filter *filter = (struct ref_filter *)data;
628 if (fnmatch(filter->pattern, ref, 0))
629 return 0;
630 return filter->fn(ref, sha, flags, filter->cb_data);
633 int peel_ref(const char *ref, unsigned char *sha1)
635 int flag;
636 unsigned char base[20];
637 struct object *o;
639 if (current_ref && (current_ref->name == ref
640 || !strcmp(current_ref->name, ref))) {
641 if (current_ref->flag & REF_KNOWS_PEELED) {
642 hashcpy(sha1, current_ref->peeled);
643 return 0;
645 hashcpy(base, current_ref->sha1);
646 goto fallback;
649 if (!resolve_ref(ref, base, 1, &flag))
650 return -1;
652 if ((flag & REF_ISPACKED)) {
653 struct ref_array *array = get_packed_refs(NULL);
654 struct ref_entry *r = search_ref_array(array, ref);
656 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
657 hashcpy(sha1, r->peeled);
658 return 0;
662 fallback:
663 o = parse_object(base);
664 if (o && o->type == OBJ_TAG) {
665 o = deref_tag(o, ref, 0);
666 if (o) {
667 hashcpy(sha1, o->sha1);
668 return 0;
671 return -1;
674 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
675 int trim, int flags, void *cb_data)
677 int retval = 0, i, p = 0, l = 0;
678 struct ref_array *packed = get_packed_refs(submodule);
679 struct ref_array *loose = get_loose_refs(submodule);
681 struct ref_array *extra = &extra_refs;
683 for (i = 0; i < extra->nr; i++)
684 retval = do_one_ref(base, fn, trim, flags, cb_data, extra->refs[i]);
686 while (p < packed->nr && l < loose->nr) {
687 struct ref_entry *entry;
688 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
689 if (!cmp) {
690 p++;
691 continue;
693 if (cmp > 0) {
694 entry = loose->refs[l++];
695 } else {
696 entry = packed->refs[p++];
698 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
699 if (retval)
700 goto end_each;
703 if (l < loose->nr) {
704 p = l;
705 packed = loose;
708 for (; p < packed->nr; p++) {
709 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
710 if (retval)
711 goto end_each;
714 end_each:
715 current_ref = NULL;
716 return retval;
720 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
722 unsigned char sha1[20];
723 int flag;
725 if (submodule) {
726 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
727 return fn("HEAD", sha1, 0, cb_data);
729 return 0;
732 if (resolve_ref("HEAD", sha1, 1, &flag))
733 return fn("HEAD", sha1, flag, cb_data);
735 return 0;
738 int head_ref(each_ref_fn fn, void *cb_data)
740 return do_head_ref(NULL, fn, cb_data);
743 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
745 return do_head_ref(submodule, fn, cb_data);
748 int for_each_ref(each_ref_fn fn, void *cb_data)
750 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
753 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
755 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
758 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
760 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
763 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
764 each_ref_fn fn, void *cb_data)
766 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
769 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
771 return for_each_ref_in("refs/tags/", fn, cb_data);
774 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
776 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
779 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
781 return for_each_ref_in("refs/heads/", fn, cb_data);
784 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
786 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
789 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
791 return for_each_ref_in("refs/remotes/", fn, cb_data);
794 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
796 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
799 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
801 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
804 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
806 struct strbuf buf = STRBUF_INIT;
807 int ret = 0;
808 unsigned char sha1[20];
809 int flag;
811 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
812 if (resolve_ref(buf.buf, sha1, 1, &flag))
813 ret = fn(buf.buf, sha1, flag, cb_data);
814 strbuf_release(&buf);
816 return ret;
819 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
821 struct strbuf buf = STRBUF_INIT;
822 int ret;
823 strbuf_addf(&buf, "%srefs/", get_git_namespace());
824 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
825 strbuf_release(&buf);
826 return ret;
829 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
830 const char *prefix, void *cb_data)
832 struct strbuf real_pattern = STRBUF_INIT;
833 struct ref_filter filter;
834 int ret;
836 if (!prefix && prefixcmp(pattern, "refs/"))
837 strbuf_addstr(&real_pattern, "refs/");
838 else if (prefix)
839 strbuf_addstr(&real_pattern, prefix);
840 strbuf_addstr(&real_pattern, pattern);
842 if (!has_glob_specials(pattern)) {
843 /* Append implied '/' '*' if not present. */
844 if (real_pattern.buf[real_pattern.len - 1] != '/')
845 strbuf_addch(&real_pattern, '/');
846 /* No need to check for '*', there is none. */
847 strbuf_addch(&real_pattern, '*');
850 filter.pattern = real_pattern.buf;
851 filter.fn = fn;
852 filter.cb_data = cb_data;
853 ret = for_each_ref(filter_refs, &filter);
855 strbuf_release(&real_pattern);
856 return ret;
859 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
861 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
864 int for_each_rawref(each_ref_fn fn, void *cb_data)
866 return do_for_each_ref(NULL, "", fn, 0,
867 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
871 * Make sure "ref" is something reasonable to have under ".git/refs/";
872 * We do not like it if:
874 * - any path component of it begins with ".", or
875 * - it has double dots "..", or
876 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
877 * - it ends with a "/".
878 * - it ends with ".lock"
879 * - it contains a "\" (backslash)
882 /* Return true iff ch is not allowed in reference names. */
883 static inline int bad_ref_char(int ch)
885 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
886 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
887 return 1;
888 /* 2.13 Pattern Matching Notation */
889 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
890 return 1;
891 return 0;
895 * Try to read one refname component from the front of ref. Return
896 * the length of the component found, or -1 if the component is not
897 * legal.
899 static int check_refname_component(const char *ref, int flags)
901 const char *cp;
902 char last = '\0';
904 for (cp = ref; ; cp++) {
905 char ch = *cp;
906 if (ch == '\0' || ch == '/')
907 break;
908 if (bad_ref_char(ch))
909 return -1; /* Illegal character in refname. */
910 if (last == '.' && ch == '.')
911 return -1; /* Refname contains "..". */
912 if (last == '@' && ch == '{')
913 return -1; /* Refname contains "@{". */
914 last = ch;
916 if (cp == ref)
917 return -1; /* Component has zero length. */
918 if (ref[0] == '.') {
919 if (!(flags & REFNAME_DOT_COMPONENT))
920 return -1; /* Component starts with '.'. */
922 * Even if leading dots are allowed, don't allow "."
923 * as a component (".." is prevented by a rule above).
925 if (ref[1] == '\0')
926 return -1; /* Component equals ".". */
928 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
929 return -1; /* Refname ends with ".lock". */
930 return cp - ref;
933 int check_refname_format(const char *ref, int flags)
935 int component_len, component_count = 0;
937 while (1) {
938 /* We are at the start of a path component. */
939 component_len = check_refname_component(ref, flags);
940 if (component_len < 0) {
941 if ((flags & REFNAME_REFSPEC_PATTERN) &&
942 ref[0] == '*' &&
943 (ref[1] == '\0' || ref[1] == '/')) {
944 /* Accept one wildcard as a full refname component. */
945 flags &= ~REFNAME_REFSPEC_PATTERN;
946 component_len = 1;
947 } else {
948 return -1;
951 component_count++;
952 if (ref[component_len] == '\0')
953 break;
954 /* Skip to next component. */
955 ref += component_len + 1;
958 if (ref[component_len - 1] == '.')
959 return -1; /* Refname ends with '.'. */
960 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
961 return -1; /* Refname has only one component. */
962 return 0;
965 const char *prettify_refname(const char *name)
967 return name + (
968 !prefixcmp(name, "refs/heads/") ? 11 :
969 !prefixcmp(name, "refs/tags/") ? 10 :
970 !prefixcmp(name, "refs/remotes/") ? 13 :
974 const char *ref_rev_parse_rules[] = {
975 "%.*s",
976 "refs/%.*s",
977 "refs/tags/%.*s",
978 "refs/heads/%.*s",
979 "refs/remotes/%.*s",
980 "refs/remotes/%.*s/HEAD",
981 NULL
984 const char *ref_fetch_rules[] = {
985 "%.*s",
986 "refs/%.*s",
987 "refs/heads/%.*s",
988 NULL
991 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
993 const char **p;
994 const int abbrev_name_len = strlen(abbrev_name);
996 for (p = rules; *p; p++) {
997 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
998 return 1;
1002 return 0;
1005 static struct ref_lock *verify_lock(struct ref_lock *lock,
1006 const unsigned char *old_sha1, int mustexist)
1008 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1009 error("Can't verify ref %s", lock->ref_name);
1010 unlock_ref(lock);
1011 return NULL;
1013 if (hashcmp(lock->old_sha1, old_sha1)) {
1014 error("Ref %s is at %s but expected %s", lock->ref_name,
1015 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1016 unlock_ref(lock);
1017 return NULL;
1019 return lock;
1022 static int remove_empty_directories(const char *file)
1024 /* we want to create a file but there is a directory there;
1025 * if that is an empty directory (or a directory that contains
1026 * only empty directories), remove them.
1028 struct strbuf path;
1029 int result;
1031 strbuf_init(&path, 20);
1032 strbuf_addstr(&path, file);
1034 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1036 strbuf_release(&path);
1038 return result;
1041 static int is_refname_available(const char *ref, const char *oldref,
1042 struct ref_array *array, int quiet)
1044 int i, namlen = strlen(ref); /* e.g. 'foo/bar' */
1045 for (i = 0; i < array->nr; i++ ) {
1046 struct ref_entry *entry = array->refs[i];
1047 /* entry->name could be 'foo' or 'foo/bar/baz' */
1048 if (!oldref || strcmp(oldref, entry->name)) {
1049 int len = strlen(entry->name);
1050 int cmplen = (namlen < len) ? namlen : len;
1051 const char *lead = (namlen < len) ? entry->name : ref;
1052 if (!strncmp(ref, entry->name, cmplen) &&
1053 lead[cmplen] == '/') {
1054 if (!quiet)
1055 error("'%s' exists; cannot create '%s'",
1056 entry->name, ref);
1057 return 0;
1061 return 1;
1064 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1066 char *ref_file;
1067 const char *orig_ref = ref;
1068 struct ref_lock *lock;
1069 int last_errno = 0;
1070 int type, lflags;
1071 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1072 int missing = 0;
1074 lock = xcalloc(1, sizeof(struct ref_lock));
1075 lock->lock_fd = -1;
1077 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1078 if (!ref && errno == EISDIR) {
1079 /* we are trying to lock foo but we used to
1080 * have foo/bar which now does not exist;
1081 * it is normal for the empty directory 'foo'
1082 * to remain.
1084 ref_file = git_path("%s", orig_ref);
1085 if (remove_empty_directories(ref_file)) {
1086 last_errno = errno;
1087 error("there are still refs under '%s'", orig_ref);
1088 goto error_return;
1090 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1092 if (type_p)
1093 *type_p = type;
1094 if (!ref) {
1095 last_errno = errno;
1096 error("unable to resolve reference %s: %s",
1097 orig_ref, strerror(errno));
1098 goto error_return;
1100 missing = is_null_sha1(lock->old_sha1);
1101 /* When the ref did not exist and we are creating it,
1102 * make sure there is no existing ref that is packed
1103 * whose name begins with our refname, nor a ref whose
1104 * name is a proper prefix of our refname.
1106 if (missing &&
1107 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1108 last_errno = ENOTDIR;
1109 goto error_return;
1112 lock->lk = xcalloc(1, sizeof(struct lock_file));
1114 lflags = LOCK_DIE_ON_ERROR;
1115 if (flags & REF_NODEREF) {
1116 ref = orig_ref;
1117 lflags |= LOCK_NODEREF;
1119 lock->ref_name = xstrdup(ref);
1120 lock->orig_ref_name = xstrdup(orig_ref);
1121 ref_file = git_path("%s", ref);
1122 if (missing)
1123 lock->force_write = 1;
1124 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1125 lock->force_write = 1;
1127 if (safe_create_leading_directories(ref_file)) {
1128 last_errno = errno;
1129 error("unable to create directory for %s", ref_file);
1130 goto error_return;
1133 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1134 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1136 error_return:
1137 unlock_ref(lock);
1138 errno = last_errno;
1139 return NULL;
1142 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1144 char refpath[PATH_MAX];
1145 if (check_refname_format(ref, 0))
1146 return NULL;
1147 strcpy(refpath, mkpath("refs/%s", ref));
1148 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1151 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1153 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1154 return NULL;
1155 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1158 static struct lock_file packlock;
1160 static int repack_without_ref(const char *refname)
1162 struct ref_array *packed;
1163 struct ref_entry *ref;
1164 int fd, i;
1166 packed = get_packed_refs(NULL);
1167 ref = search_ref_array(packed, refname);
1168 if (ref == NULL)
1169 return 0;
1170 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1171 if (fd < 0) {
1172 unable_to_lock_error(git_path("packed-refs"), errno);
1173 return error("cannot delete '%s' from packed refs", refname);
1176 for (i = 0; i < packed->nr; i++) {
1177 char line[PATH_MAX + 100];
1178 int len;
1180 ref = packed->refs[i];
1182 if (!strcmp(refname, ref->name))
1183 continue;
1184 len = snprintf(line, sizeof(line), "%s %s\n",
1185 sha1_to_hex(ref->sha1), ref->name);
1186 /* this should not happen but just being defensive */
1187 if (len > sizeof(line))
1188 die("too long a refname '%s'", ref->name);
1189 write_or_die(fd, line, len);
1191 return commit_lock_file(&packlock);
1194 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1196 struct ref_lock *lock;
1197 int err, i = 0, ret = 0, flag = 0;
1199 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1200 if (!lock)
1201 return 1;
1202 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1203 /* loose */
1204 const char *path;
1206 if (!(delopt & REF_NODEREF)) {
1207 i = strlen(lock->lk->filename) - 5; /* .lock */
1208 lock->lk->filename[i] = 0;
1209 path = lock->lk->filename;
1210 } else {
1211 path = git_path("%s", refname);
1213 err = unlink_or_warn(path);
1214 if (err && errno != ENOENT)
1215 ret = 1;
1217 if (!(delopt & REF_NODEREF))
1218 lock->lk->filename[i] = '.';
1220 /* removing the loose one could have resurrected an earlier
1221 * packed one. Also, if it was not loose we need to repack
1222 * without it.
1224 ret |= repack_without_ref(refname);
1226 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1227 invalidate_cached_refs();
1228 unlock_ref(lock);
1229 return ret;
1233 * People using contrib's git-new-workdir have .git/logs/refs ->
1234 * /some/other/path/.git/logs/refs, and that may live on another device.
1236 * IOW, to avoid cross device rename errors, the temporary renamed log must
1237 * live into logs/refs.
1239 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1241 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1243 static const char renamed_ref[] = "RENAMED-REF";
1244 unsigned char sha1[20], orig_sha1[20];
1245 int flag = 0, logmoved = 0;
1246 struct ref_lock *lock;
1247 struct stat loginfo;
1248 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1249 const char *symref = NULL;
1251 if (log && S_ISLNK(loginfo.st_mode))
1252 return error("reflog for %s is a symlink", oldref);
1254 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1255 if (flag & REF_ISSYMREF)
1256 return error("refname %s is a symbolic ref, renaming it is not supported",
1257 oldref);
1258 if (!symref)
1259 return error("refname %s not found", oldref);
1261 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1262 return 1;
1264 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1265 return 1;
1267 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1268 if (!lock)
1269 return error("unable to lock %s", renamed_ref);
1270 lock->force_write = 1;
1271 if (write_ref_sha1(lock, orig_sha1, logmsg))
1272 return error("unable to save current sha1 in %s", renamed_ref);
1274 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1275 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1276 oldref, strerror(errno));
1278 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1279 error("unable to delete old %s", oldref);
1280 goto rollback;
1283 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1284 if (errno==EISDIR) {
1285 if (remove_empty_directories(git_path("%s", newref))) {
1286 error("Directory not empty: %s", newref);
1287 goto rollback;
1289 } else {
1290 error("unable to delete existing %s", newref);
1291 goto rollback;
1295 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1296 error("unable to create directory for %s", newref);
1297 goto rollback;
1300 retry:
1301 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1302 if (errno==EISDIR || errno==ENOTDIR) {
1304 * rename(a, b) when b is an existing
1305 * directory ought to result in ISDIR, but
1306 * Solaris 5.8 gives ENOTDIR. Sheesh.
1308 if (remove_empty_directories(git_path("logs/%s", newref))) {
1309 error("Directory not empty: logs/%s", newref);
1310 goto rollback;
1312 goto retry;
1313 } else {
1314 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1315 newref, strerror(errno));
1316 goto rollback;
1319 logmoved = log;
1321 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1322 if (!lock) {
1323 error("unable to lock %s for update", newref);
1324 goto rollback;
1326 lock->force_write = 1;
1327 hashcpy(lock->old_sha1, orig_sha1);
1328 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1329 error("unable to write current sha1 into %s", newref);
1330 goto rollback;
1333 return 0;
1335 rollback:
1336 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1337 if (!lock) {
1338 error("unable to lock %s for rollback", oldref);
1339 goto rollbacklog;
1342 lock->force_write = 1;
1343 flag = log_all_ref_updates;
1344 log_all_ref_updates = 0;
1345 if (write_ref_sha1(lock, orig_sha1, NULL))
1346 error("unable to write current sha1 into %s", oldref);
1347 log_all_ref_updates = flag;
1349 rollbacklog:
1350 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1351 error("unable to restore logfile %s from %s: %s",
1352 oldref, newref, strerror(errno));
1353 if (!logmoved && log &&
1354 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1355 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1356 oldref, strerror(errno));
1358 return 1;
1361 int close_ref(struct ref_lock *lock)
1363 if (close_lock_file(lock->lk))
1364 return -1;
1365 lock->lock_fd = -1;
1366 return 0;
1369 int commit_ref(struct ref_lock *lock)
1371 if (commit_lock_file(lock->lk))
1372 return -1;
1373 lock->lock_fd = -1;
1374 return 0;
1377 void unlock_ref(struct ref_lock *lock)
1379 /* Do not free lock->lk -- atexit() still looks at them */
1380 if (lock->lk)
1381 rollback_lock_file(lock->lk);
1382 free(lock->ref_name);
1383 free(lock->orig_ref_name);
1384 free(lock);
1388 * copy the reflog message msg to buf, which has been allocated sufficiently
1389 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1390 * because reflog file is one line per entry.
1392 static int copy_msg(char *buf, const char *msg)
1394 char *cp = buf;
1395 char c;
1396 int wasspace = 1;
1398 *cp++ = '\t';
1399 while ((c = *msg++)) {
1400 if (wasspace && isspace(c))
1401 continue;
1402 wasspace = isspace(c);
1403 if (wasspace)
1404 c = ' ';
1405 *cp++ = c;
1407 while (buf < cp && isspace(cp[-1]))
1408 cp--;
1409 *cp++ = '\n';
1410 return cp - buf;
1413 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1415 int logfd, oflags = O_APPEND | O_WRONLY;
1417 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1418 if (log_all_ref_updates &&
1419 (!prefixcmp(ref_name, "refs/heads/") ||
1420 !prefixcmp(ref_name, "refs/remotes/") ||
1421 !prefixcmp(ref_name, "refs/notes/") ||
1422 !strcmp(ref_name, "HEAD"))) {
1423 if (safe_create_leading_directories(logfile) < 0)
1424 return error("unable to create directory for %s",
1425 logfile);
1426 oflags |= O_CREAT;
1429 logfd = open(logfile, oflags, 0666);
1430 if (logfd < 0) {
1431 if (!(oflags & O_CREAT) && errno == ENOENT)
1432 return 0;
1434 if ((oflags & O_CREAT) && errno == EISDIR) {
1435 if (remove_empty_directories(logfile)) {
1436 return error("There are still logs under '%s'",
1437 logfile);
1439 logfd = open(logfile, oflags, 0666);
1442 if (logfd < 0)
1443 return error("Unable to append to %s: %s",
1444 logfile, strerror(errno));
1447 adjust_shared_perm(logfile);
1448 close(logfd);
1449 return 0;
1452 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1453 const unsigned char *new_sha1, const char *msg)
1455 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1456 unsigned maxlen, len;
1457 int msglen;
1458 char log_file[PATH_MAX];
1459 char *logrec;
1460 const char *committer;
1462 if (log_all_ref_updates < 0)
1463 log_all_ref_updates = !is_bare_repository();
1465 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1466 if (result)
1467 return result;
1469 logfd = open(log_file, oflags);
1470 if (logfd < 0)
1471 return 0;
1472 msglen = msg ? strlen(msg) : 0;
1473 committer = git_committer_info(0);
1474 maxlen = strlen(committer) + msglen + 100;
1475 logrec = xmalloc(maxlen);
1476 len = sprintf(logrec, "%s %s %s\n",
1477 sha1_to_hex(old_sha1),
1478 sha1_to_hex(new_sha1),
1479 committer);
1480 if (msglen)
1481 len += copy_msg(logrec + len - 1, msg) - 1;
1482 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1483 free(logrec);
1484 if (close(logfd) != 0 || written != len)
1485 return error("Unable to append to %s", log_file);
1486 return 0;
1489 static int is_branch(const char *refname)
1491 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1494 int write_ref_sha1(struct ref_lock *lock,
1495 const unsigned char *sha1, const char *logmsg)
1497 static char term = '\n';
1498 struct object *o;
1500 if (!lock)
1501 return -1;
1502 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1503 unlock_ref(lock);
1504 return 0;
1506 o = parse_object(sha1);
1507 if (!o) {
1508 error("Trying to write ref %s with nonexistent object %s",
1509 lock->ref_name, sha1_to_hex(sha1));
1510 unlock_ref(lock);
1511 return -1;
1513 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1514 error("Trying to write non-commit object %s to branch %s",
1515 sha1_to_hex(sha1), lock->ref_name);
1516 unlock_ref(lock);
1517 return -1;
1519 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1520 write_in_full(lock->lock_fd, &term, 1) != 1
1521 || close_ref(lock) < 0) {
1522 error("Couldn't write %s", lock->lk->filename);
1523 unlock_ref(lock);
1524 return -1;
1526 invalidate_cached_refs();
1527 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1528 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1529 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1530 unlock_ref(lock);
1531 return -1;
1533 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1535 * Special hack: If a branch is updated directly and HEAD
1536 * points to it (may happen on the remote side of a push
1537 * for example) then logically the HEAD reflog should be
1538 * updated too.
1539 * A generic solution implies reverse symref information,
1540 * but finding all symrefs pointing to the given branch
1541 * would be rather costly for this rare event (the direct
1542 * update of a branch) to be worth it. So let's cheat and
1543 * check with HEAD only which should cover 99% of all usage
1544 * scenarios (even 100% of the default ones).
1546 unsigned char head_sha1[20];
1547 int head_flag;
1548 const char *head_ref;
1549 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1550 if (head_ref && (head_flag & REF_ISSYMREF) &&
1551 !strcmp(head_ref, lock->ref_name))
1552 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1554 if (commit_ref(lock)) {
1555 error("Couldn't set %s", lock->ref_name);
1556 unlock_ref(lock);
1557 return -1;
1559 unlock_ref(lock);
1560 return 0;
1563 int create_symref(const char *ref_target, const char *refs_heads_master,
1564 const char *logmsg)
1566 const char *lockpath;
1567 char ref[1000];
1568 int fd, len, written;
1569 char *git_HEAD = git_pathdup("%s", ref_target);
1570 unsigned char old_sha1[20], new_sha1[20];
1572 if (logmsg && read_ref(ref_target, old_sha1))
1573 hashclr(old_sha1);
1575 if (safe_create_leading_directories(git_HEAD) < 0)
1576 return error("unable to create directory for %s", git_HEAD);
1578 #ifndef NO_SYMLINK_HEAD
1579 if (prefer_symlink_refs) {
1580 unlink(git_HEAD);
1581 if (!symlink(refs_heads_master, git_HEAD))
1582 goto done;
1583 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1585 #endif
1587 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1588 if (sizeof(ref) <= len) {
1589 error("refname too long: %s", refs_heads_master);
1590 goto error_free_return;
1592 lockpath = mkpath("%s.lock", git_HEAD);
1593 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1594 if (fd < 0) {
1595 error("Unable to open %s for writing", lockpath);
1596 goto error_free_return;
1598 written = write_in_full(fd, ref, len);
1599 if (close(fd) != 0 || written != len) {
1600 error("Unable to write to %s", lockpath);
1601 goto error_unlink_return;
1603 if (rename(lockpath, git_HEAD) < 0) {
1604 error("Unable to create %s", git_HEAD);
1605 goto error_unlink_return;
1607 if (adjust_shared_perm(git_HEAD)) {
1608 error("Unable to fix permissions on %s", lockpath);
1609 error_unlink_return:
1610 unlink_or_warn(lockpath);
1611 error_free_return:
1612 free(git_HEAD);
1613 return -1;
1616 #ifndef NO_SYMLINK_HEAD
1617 done:
1618 #endif
1619 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1620 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1622 free(git_HEAD);
1623 return 0;
1626 static char *ref_msg(const char *line, const char *endp)
1628 const char *ep;
1629 line += 82;
1630 ep = memchr(line, '\n', endp - line);
1631 if (!ep)
1632 ep = endp;
1633 return xmemdupz(line, ep - line);
1636 int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *sha1, char **msg, unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1638 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1639 char *tz_c;
1640 int logfd, tz, reccnt = 0;
1641 struct stat st;
1642 unsigned long date;
1643 unsigned char logged_sha1[20];
1644 void *log_mapped;
1645 size_t mapsz;
1647 logfile = git_path("logs/%s", ref);
1648 logfd = open(logfile, O_RDONLY, 0);
1649 if (logfd < 0)
1650 die_errno("Unable to read log '%s'", logfile);
1651 fstat(logfd, &st);
1652 if (!st.st_size)
1653 die("Log %s is empty.", logfile);
1654 mapsz = xsize_t(st.st_size);
1655 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1656 logdata = log_mapped;
1657 close(logfd);
1659 lastrec = NULL;
1660 rec = logend = logdata + st.st_size;
1661 while (logdata < rec) {
1662 reccnt++;
1663 if (logdata < rec && *(rec-1) == '\n')
1664 rec--;
1665 lastgt = NULL;
1666 while (logdata < rec && *(rec-1) != '\n') {
1667 rec--;
1668 if (*rec == '>')
1669 lastgt = rec;
1671 if (!lastgt)
1672 die("Log %s is corrupt.", logfile);
1673 date = strtoul(lastgt + 1, &tz_c, 10);
1674 if (date <= at_time || cnt == 0) {
1675 tz = strtoul(tz_c, NULL, 10);
1676 if (msg)
1677 *msg = ref_msg(rec, logend);
1678 if (cutoff_time)
1679 *cutoff_time = date;
1680 if (cutoff_tz)
1681 *cutoff_tz = tz;
1682 if (cutoff_cnt)
1683 *cutoff_cnt = reccnt - 1;
1684 if (lastrec) {
1685 if (get_sha1_hex(lastrec, logged_sha1))
1686 die("Log %s is corrupt.", logfile);
1687 if (get_sha1_hex(rec + 41, sha1))
1688 die("Log %s is corrupt.", logfile);
1689 if (hashcmp(logged_sha1, sha1)) {
1690 warning("Log %s has gap after %s.",
1691 logfile, show_date(date, tz, DATE_RFC2822));
1694 else if (date == at_time) {
1695 if (get_sha1_hex(rec + 41, sha1))
1696 die("Log %s is corrupt.", logfile);
1698 else {
1699 if (get_sha1_hex(rec + 41, logged_sha1))
1700 die("Log %s is corrupt.", logfile);
1701 if (hashcmp(logged_sha1, sha1)) {
1702 warning("Log %s unexpectedly ended on %s.",
1703 logfile, show_date(date, tz, DATE_RFC2822));
1706 munmap(log_mapped, mapsz);
1707 return 0;
1709 lastrec = rec;
1710 if (cnt > 0)
1711 cnt--;
1714 rec = logdata;
1715 while (rec < logend && *rec != '>' && *rec != '\n')
1716 rec++;
1717 if (rec == logend || *rec == '\n')
1718 die("Log %s is corrupt.", logfile);
1719 date = strtoul(rec + 1, &tz_c, 10);
1720 tz = strtoul(tz_c, NULL, 10);
1721 if (get_sha1_hex(logdata, sha1))
1722 die("Log %s is corrupt.", logfile);
1723 if (is_null_sha1(sha1)) {
1724 if (get_sha1_hex(logdata + 41, sha1))
1725 die("Log %s is corrupt.", logfile);
1727 if (msg)
1728 *msg = ref_msg(logdata, logend);
1729 munmap(log_mapped, mapsz);
1731 if (cutoff_time)
1732 *cutoff_time = date;
1733 if (cutoff_tz)
1734 *cutoff_tz = tz;
1735 if (cutoff_cnt)
1736 *cutoff_cnt = reccnt;
1737 return 1;
1740 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1742 const char *logfile;
1743 FILE *logfp;
1744 struct strbuf sb = STRBUF_INIT;
1745 int ret = 0;
1747 logfile = git_path("logs/%s", ref);
1748 logfp = fopen(logfile, "r");
1749 if (!logfp)
1750 return -1;
1752 if (ofs) {
1753 struct stat statbuf;
1754 if (fstat(fileno(logfp), &statbuf) ||
1755 statbuf.st_size < ofs ||
1756 fseek(logfp, -ofs, SEEK_END) ||
1757 strbuf_getwholeline(&sb, logfp, '\n')) {
1758 fclose(logfp);
1759 strbuf_release(&sb);
1760 return -1;
1764 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1765 unsigned char osha1[20], nsha1[20];
1766 char *email_end, *message;
1767 unsigned long timestamp;
1768 int tz;
1770 /* old SP new SP name <email> SP time TAB msg LF */
1771 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1772 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1773 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1774 !(email_end = strchr(sb.buf + 82, '>')) ||
1775 email_end[1] != ' ' ||
1776 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1777 !message || message[0] != ' ' ||
1778 (message[1] != '+' && message[1] != '-') ||
1779 !isdigit(message[2]) || !isdigit(message[3]) ||
1780 !isdigit(message[4]) || !isdigit(message[5]))
1781 continue; /* corrupt? */
1782 email_end[1] = '\0';
1783 tz = strtol(message + 1, NULL, 10);
1784 if (message[6] != '\t')
1785 message += 6;
1786 else
1787 message += 7;
1788 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1789 cb_data);
1790 if (ret)
1791 break;
1793 fclose(logfp);
1794 strbuf_release(&sb);
1795 return ret;
1798 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1800 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1803 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1805 DIR *dir = opendir(git_path("logs/%s", base));
1806 int retval = 0;
1808 if (dir) {
1809 struct dirent *de;
1810 int baselen = strlen(base);
1811 char *log = xmalloc(baselen + 257);
1813 memcpy(log, base, baselen);
1814 if (baselen && base[baselen-1] != '/')
1815 log[baselen++] = '/';
1817 while ((de = readdir(dir)) != NULL) {
1818 struct stat st;
1819 int namelen;
1821 if (de->d_name[0] == '.')
1822 continue;
1823 namelen = strlen(de->d_name);
1824 if (namelen > 255)
1825 continue;
1826 if (has_extension(de->d_name, ".lock"))
1827 continue;
1828 memcpy(log + baselen, de->d_name, namelen+1);
1829 if (stat(git_path("logs/%s", log), &st) < 0)
1830 continue;
1831 if (S_ISDIR(st.st_mode)) {
1832 retval = do_for_each_reflog(log, fn, cb_data);
1833 } else {
1834 unsigned char sha1[20];
1835 if (!resolve_ref(log, sha1, 0, NULL))
1836 retval = error("bad ref for %s", log);
1837 else
1838 retval = fn(log, sha1, 0, cb_data);
1840 if (retval)
1841 break;
1843 free(log);
1844 closedir(dir);
1846 else if (*base)
1847 return errno;
1848 return retval;
1851 int for_each_reflog(each_ref_fn fn, void *cb_data)
1853 return do_for_each_reflog("", fn, cb_data);
1856 int update_ref(const char *action, const char *refname,
1857 const unsigned char *sha1, const unsigned char *oldval,
1858 int flags, enum action_on_err onerr)
1860 static struct ref_lock *lock;
1861 lock = lock_any_ref_for_update(refname, oldval, flags);
1862 if (!lock) {
1863 const char *str = "Cannot lock the ref '%s'.";
1864 switch (onerr) {
1865 case MSG_ON_ERR: error(str, refname); break;
1866 case DIE_ON_ERR: die(str, refname); break;
1867 case QUIET_ON_ERR: break;
1869 return 1;
1871 if (write_ref_sha1(lock, sha1, action) < 0) {
1872 const char *str = "Cannot update the ref '%s'.";
1873 switch (onerr) {
1874 case MSG_ON_ERR: error(str, refname); break;
1875 case DIE_ON_ERR: die(str, refname); break;
1876 case QUIET_ON_ERR: break;
1878 return 1;
1880 return 0;
1883 int ref_exists(const char *refname)
1885 unsigned char sha1[20];
1886 return !!resolve_ref(refname, sha1, 1, NULL);
1889 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1891 for ( ; list; list = list->next)
1892 if (!strcmp(list->name, name))
1893 return (struct ref *)list;
1894 return NULL;
1898 * generate a format suitable for scanf from a ref_rev_parse_rules
1899 * rule, that is replace the "%.*s" spec with a "%s" spec
1901 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1903 char *spec;
1905 spec = strstr(rule, "%.*s");
1906 if (!spec || strstr(spec + 4, "%.*s"))
1907 die("invalid rule in ref_rev_parse_rules: %s", rule);
1909 /* copy all until spec */
1910 strncpy(scanf_fmt, rule, spec - rule);
1911 scanf_fmt[spec - rule] = '\0';
1912 /* copy new spec */
1913 strcat(scanf_fmt, "%s");
1914 /* copy remaining rule */
1915 strcat(scanf_fmt, spec + 4);
1917 return;
1920 char *shorten_unambiguous_ref(const char *ref, int strict)
1922 int i;
1923 static char **scanf_fmts;
1924 static int nr_rules;
1925 char *short_name;
1927 /* pre generate scanf formats from ref_rev_parse_rules[] */
1928 if (!nr_rules) {
1929 size_t total_len = 0;
1931 /* the rule list is NULL terminated, count them first */
1932 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1933 /* no +1 because strlen("%s") < strlen("%.*s") */
1934 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1936 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1938 total_len = 0;
1939 for (i = 0; i < nr_rules; i++) {
1940 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1941 + total_len;
1942 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1943 total_len += strlen(ref_rev_parse_rules[i]);
1947 /* bail out if there are no rules */
1948 if (!nr_rules)
1949 return xstrdup(ref);
1951 /* buffer for scanf result, at most ref must fit */
1952 short_name = xstrdup(ref);
1954 /* skip first rule, it will always match */
1955 for (i = nr_rules - 1; i > 0 ; --i) {
1956 int j;
1957 int rules_to_fail = i;
1958 int short_name_len;
1960 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1961 continue;
1963 short_name_len = strlen(short_name);
1966 * in strict mode, all (except the matched one) rules
1967 * must fail to resolve to a valid non-ambiguous ref
1969 if (strict)
1970 rules_to_fail = nr_rules;
1973 * check if the short name resolves to a valid ref,
1974 * but use only rules prior to the matched one
1976 for (j = 0; j < rules_to_fail; j++) {
1977 const char *rule = ref_rev_parse_rules[j];
1978 unsigned char short_objectname[20];
1979 char refname[PATH_MAX];
1981 /* skip matched rule */
1982 if (i == j)
1983 continue;
1986 * the short name is ambiguous, if it resolves
1987 * (with this previous rule) to a valid ref
1988 * read_ref() returns 0 on success
1990 mksnpath(refname, sizeof(refname),
1991 rule, short_name_len, short_name);
1992 if (!read_ref(refname, short_objectname))
1993 break;
1997 * short name is non-ambiguous if all previous rules
1998 * haven't resolved to a valid ref
2000 if (j == rules_to_fail)
2001 return short_name;
2004 free(short_name);
2005 return xstrdup(ref);