submodule: Use cat instead of echo to avoid DOS line-endings
[git/dscho.git] / refs.c
blobc9f68353517bb6dcd4b19114a5191fdf9075a8d1
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
7 /* ISSYMREF=0x01, ISPACKED=0x02 and ISBROKEN=0x04 are public interfaces */
8 #define REF_KNOWS_PEELED 0x10
10 struct ref_entry {
11 unsigned char flag; /* ISSYMREF? ISPACKED? */
12 unsigned char sha1[20];
13 unsigned char peeled[20];
14 /* The full name of the reference (e.g., "refs/heads/master"): */
15 char name[FLEX_ARRAY];
18 struct ref_array {
19 int nr, alloc;
22 * Entries with index 0 <= i < sorted are sorted by name. New
23 * entries are appended to the list unsorted, and are sorted
24 * only when required; thus we avoid the need to sort the list
25 * after the addition of every reference.
27 int sorted;
29 struct ref_entry **refs;
33 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
34 * Return a pointer to the refname within the line (null-terminated),
35 * or NULL if there was a problem.
37 static const char *parse_ref_line(char *line, unsigned char *sha1)
40 * 42: the answer to everything.
42 * In this case, it happens to be the answer to
43 * 40 (length of sha1 hex representation)
44 * +1 (space in between hex and name)
45 * +1 (newline at the end of the line)
47 int len = strlen(line) - 42;
49 if (len <= 0)
50 return NULL;
51 if (get_sha1_hex(line, sha1) < 0)
52 return NULL;
53 if (!isspace(line[40]))
54 return NULL;
55 line += 41;
56 if (isspace(*line))
57 return NULL;
58 if (line[len] != '\n')
59 return NULL;
60 line[len] = 0;
62 return line;
65 static struct ref_entry *create_ref_entry(const char *refname,
66 const unsigned char *sha1, int flag,
67 int check_name)
69 int len;
70 struct ref_entry *ref;
72 if (check_name &&
73 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
74 die("Reference has invalid format: '%s'", refname);
75 len = strlen(refname) + 1;
76 ref = xmalloc(sizeof(struct ref_entry) + len);
77 hashcpy(ref->sha1, sha1);
78 hashclr(ref->peeled);
79 memcpy(ref->name, refname, len);
80 ref->flag = flag;
81 return ref;
84 /* Add a ref_entry to the end of the ref_array (unsorted). */
85 static void add_ref(struct ref_array *refs, struct ref_entry *ref)
87 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
88 refs->refs[refs->nr++] = ref;
91 static int ref_entry_cmp(const void *a, const void *b)
93 struct ref_entry *one = *(struct ref_entry **)a;
94 struct ref_entry *two = *(struct ref_entry **)b;
95 return strcmp(one->name, two->name);
99 * Emit a warning and return true iff ref1 and ref2 have the same name
100 * and the same sha1. Die if they have the same name but different
101 * sha1s.
103 static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
105 if (!strcmp(ref1->name, ref2->name)) {
106 /* Duplicate name; make sure that the SHA1s match: */
107 if (hashcmp(ref1->sha1, ref2->sha1))
108 die("Duplicated ref, and SHA1s don't match: %s",
109 ref1->name);
110 warning("Duplicated ref: %s", ref1->name);
111 return 1;
112 } else {
113 return 0;
118 * Sort the entries in array (if they are not already sorted).
120 static void sort_ref_array(struct ref_array *array)
122 int i, j;
125 * This check also prevents passing a zero-length array to qsort(),
126 * which is a problem on some platforms.
128 if (array->sorted == array->nr)
129 return;
131 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
133 /* Remove any duplicates from the ref_array */
134 i = 0;
135 for (j = 1; j < array->nr; j++) {
136 if (is_dup_ref(array->refs[i], array->refs[j])) {
137 free(array->refs[j]);
138 continue;
140 array->refs[++i] = array->refs[j];
142 array->sorted = array->nr = i + 1;
145 static struct ref_entry *search_ref_array(struct ref_array *array, const char *refname)
147 struct ref_entry *e, **r;
148 int len;
150 if (refname == NULL)
151 return NULL;
153 if (!array->nr)
154 return NULL;
155 sort_ref_array(array);
156 len = strlen(refname) + 1;
157 e = xmalloc(sizeof(struct ref_entry) + len);
158 memcpy(e->name, refname, len);
160 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
162 free(e);
164 if (r == NULL)
165 return NULL;
167 return *r;
171 * Future: need to be in "struct repository"
172 * when doing a full libification.
174 static struct ref_cache {
175 struct ref_cache *next;
176 char did_loose;
177 char did_packed;
178 struct ref_array loose;
179 struct ref_array packed;
180 /* The submodule name, or "" for the main repo. */
181 char name[FLEX_ARRAY];
182 } *ref_cache;
184 static struct ref_entry *current_ref;
186 static void clear_ref_array(struct ref_array *array)
188 int i;
189 for (i = 0; i < array->nr; i++)
190 free(array->refs[i]);
191 free(array->refs);
192 array->sorted = array->nr = array->alloc = 0;
193 array->refs = NULL;
196 static void clear_packed_ref_cache(struct ref_cache *refs)
198 if (refs->did_packed)
199 clear_ref_array(&refs->packed);
200 refs->did_packed = 0;
203 static void clear_loose_ref_cache(struct ref_cache *refs)
205 if (refs->did_loose)
206 clear_ref_array(&refs->loose);
207 refs->did_loose = 0;
210 static struct ref_cache *create_ref_cache(const char *submodule)
212 int len;
213 struct ref_cache *refs;
214 if (!submodule)
215 submodule = "";
216 len = strlen(submodule) + 1;
217 refs = xcalloc(1, sizeof(struct ref_cache) + len);
218 memcpy(refs->name, submodule, len);
219 return refs;
223 * Return a pointer to a ref_cache for the specified submodule. For
224 * the main repository, use submodule==NULL. The returned structure
225 * will be allocated and initialized but not necessarily populated; it
226 * should not be freed.
228 static struct ref_cache *get_ref_cache(const char *submodule)
230 struct ref_cache *refs = ref_cache;
231 if (!submodule)
232 submodule = "";
233 while (refs) {
234 if (!strcmp(submodule, refs->name))
235 return refs;
236 refs = refs->next;
239 refs = create_ref_cache(submodule);
240 refs->next = ref_cache;
241 ref_cache = refs;
242 return refs;
245 void invalidate_ref_cache(const char *submodule)
247 struct ref_cache *refs = get_ref_cache(submodule);
248 clear_packed_ref_cache(refs);
249 clear_loose_ref_cache(refs);
252 static void read_packed_refs(FILE *f, struct ref_array *array)
254 struct ref_entry *last = NULL;
255 char refline[PATH_MAX];
256 int flag = REF_ISPACKED;
258 while (fgets(refline, sizeof(refline), f)) {
259 unsigned char sha1[20];
260 const char *refname;
261 static const char header[] = "# pack-refs with:";
263 if (!strncmp(refline, header, sizeof(header)-1)) {
264 const char *traits = refline + sizeof(header) - 1;
265 if (strstr(traits, " peeled "))
266 flag |= REF_KNOWS_PEELED;
267 /* perhaps other traits later as well */
268 continue;
271 refname = parse_ref_line(refline, sha1);
272 if (refname) {
273 last = create_ref_entry(refname, sha1, flag, 1);
274 add_ref(array, last);
275 continue;
277 if (last &&
278 refline[0] == '^' &&
279 strlen(refline) == 42 &&
280 refline[41] == '\n' &&
281 !get_sha1_hex(refline + 1, sha1))
282 hashcpy(last->peeled, sha1);
286 static struct ref_array *get_packed_refs(struct ref_cache *refs)
288 if (!refs->did_packed) {
289 const char *packed_refs_file;
290 FILE *f;
292 if (*refs->name)
293 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
294 else
295 packed_refs_file = git_path("packed-refs");
296 f = fopen(packed_refs_file, "r");
297 if (f) {
298 read_packed_refs(f, &refs->packed);
299 fclose(f);
301 refs->did_packed = 1;
303 return &refs->packed;
306 void add_packed_ref(const char *refname, const unsigned char *sha1)
308 add_ref(get_packed_refs(get_ref_cache(NULL)),
309 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
312 static void get_ref_dir(struct ref_cache *refs, const char *base,
313 struct ref_array *array)
315 DIR *dir;
316 const char *path;
318 if (*refs->name)
319 path = git_path_submodule(refs->name, "%s", base);
320 else
321 path = git_path("%s", base);
324 dir = opendir(path);
326 if (dir) {
327 struct dirent *de;
328 int baselen = strlen(base);
329 char *refname = xmalloc(baselen + 257);
331 memcpy(refname, base, baselen);
332 if (baselen && base[baselen-1] != '/')
333 refname[baselen++] = '/';
335 while ((de = readdir(dir)) != NULL) {
336 unsigned char sha1[20];
337 struct stat st;
338 int flag;
339 int namelen;
340 const char *refdir;
342 if (de->d_name[0] == '.')
343 continue;
344 namelen = strlen(de->d_name);
345 if (namelen > 255)
346 continue;
347 if (has_extension(de->d_name, ".lock"))
348 continue;
349 memcpy(refname + baselen, de->d_name, namelen+1);
350 refdir = *refs->name
351 ? git_path_submodule(refs->name, "%s", refname)
352 : git_path("%s", refname);
353 if (stat(refdir, &st) < 0)
354 continue;
355 if (S_ISDIR(st.st_mode)) {
356 get_ref_dir(refs, refname, array);
357 continue;
359 if (*refs->name) {
360 hashclr(sha1);
361 flag = 0;
362 if (resolve_gitlink_ref(refs->name, refname, sha1) < 0) {
363 hashclr(sha1);
364 flag |= REF_ISBROKEN;
366 } else if (read_ref_full(refname, sha1, 1, &flag)) {
367 hashclr(sha1);
368 flag |= REF_ISBROKEN;
370 add_ref(array, create_ref_entry(refname, sha1, flag, 1));
372 free(refname);
373 closedir(dir);
377 struct warn_if_dangling_data {
378 FILE *fp;
379 const char *refname;
380 const char *msg_fmt;
383 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
384 int flags, void *cb_data)
386 struct warn_if_dangling_data *d = cb_data;
387 const char *resolves_to;
388 unsigned char junk[20];
390 if (!(flags & REF_ISSYMREF))
391 return 0;
393 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
394 if (!resolves_to || strcmp(resolves_to, d->refname))
395 return 0;
397 fprintf(d->fp, d->msg_fmt, refname);
398 return 0;
401 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
403 struct warn_if_dangling_data data;
405 data.fp = fp;
406 data.refname = refname;
407 data.msg_fmt = msg_fmt;
408 for_each_rawref(warn_if_dangling_symref, &data);
411 static struct ref_array *get_loose_refs(struct ref_cache *refs)
413 if (!refs->did_loose) {
414 get_ref_dir(refs, "refs", &refs->loose);
415 refs->did_loose = 1;
417 return &refs->loose;
420 /* We allow "recursive" symbolic refs. Only within reason, though */
421 #define MAXDEPTH 5
422 #define MAXREFLEN (1024)
425 * Called by resolve_gitlink_ref_recursive() after it failed to read
426 * from the loose refs in ref_cache refs. Find <refname> in the
427 * packed-refs file for the submodule.
429 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
430 const char *refname, unsigned char *sha1)
432 struct ref_entry *ref;
433 struct ref_array *array = get_packed_refs(refs);
435 ref = search_ref_array(array, refname);
436 if (ref == NULL)
437 return -1;
439 memcpy(sha1, ref->sha1, 20);
440 return 0;
443 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
444 const char *refname, unsigned char *sha1,
445 int recursion)
447 int fd, len;
448 char buffer[128], *p;
449 char *path;
451 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
452 return -1;
453 path = *refs->name
454 ? git_path_submodule(refs->name, "%s", refname)
455 : git_path("%s", refname);
456 fd = open(path, O_RDONLY);
457 if (fd < 0)
458 return resolve_gitlink_packed_ref(refs, refname, sha1);
460 len = read(fd, buffer, sizeof(buffer)-1);
461 close(fd);
462 if (len < 0)
463 return -1;
464 while (len && isspace(buffer[len-1]))
465 len--;
466 buffer[len] = 0;
468 /* Was it a detached head or an old-fashioned symlink? */
469 if (!get_sha1_hex(buffer, sha1))
470 return 0;
472 /* Symref? */
473 if (strncmp(buffer, "ref:", 4))
474 return -1;
475 p = buffer + 4;
476 while (isspace(*p))
477 p++;
479 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
482 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
484 int len = strlen(path), retval;
485 char *submodule;
486 struct ref_cache *refs;
488 while (len && path[len-1] == '/')
489 len--;
490 if (!len)
491 return -1;
492 submodule = xstrndup(path, len);
493 refs = get_ref_cache(submodule);
494 free(submodule);
496 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
497 return retval;
501 * Try to read ref from the packed references. On success, set sha1
502 * and return 0; otherwise, return -1.
504 static int get_packed_ref(const char *refname, unsigned char *sha1)
506 struct ref_array *packed = get_packed_refs(get_ref_cache(NULL));
507 struct ref_entry *entry = search_ref_array(packed, refname);
508 if (entry) {
509 hashcpy(sha1, entry->sha1);
510 return 0;
512 return -1;
515 const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
517 int depth = MAXDEPTH;
518 ssize_t len;
519 char buffer[256];
520 static char refname_buffer[256];
522 if (flag)
523 *flag = 0;
525 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
526 return NULL;
528 for (;;) {
529 char path[PATH_MAX];
530 struct stat st;
531 char *buf;
532 int fd;
534 if (--depth < 0)
535 return NULL;
537 git_snpath(path, sizeof(path), "%s", refname);
539 if (lstat(path, &st) < 0) {
540 if (errno != ENOENT)
541 return NULL;
543 * The loose reference file does not exist;
544 * check for a packed reference.
546 if (!get_packed_ref(refname, sha1)) {
547 if (flag)
548 *flag |= REF_ISPACKED;
549 return refname;
551 /* The reference is not a packed reference, either. */
552 if (reading) {
553 return NULL;
554 } else {
555 hashclr(sha1);
556 return refname;
560 /* Follow "normalized" - ie "refs/.." symlinks by hand */
561 if (S_ISLNK(st.st_mode)) {
562 len = readlink(path, buffer, sizeof(buffer)-1);
563 if (len < 0)
564 return NULL;
565 buffer[len] = 0;
566 if (!prefixcmp(buffer, "refs/") &&
567 !check_refname_format(buffer, 0)) {
568 strcpy(refname_buffer, buffer);
569 refname = refname_buffer;
570 if (flag)
571 *flag |= REF_ISSYMREF;
572 continue;
576 /* Is it a directory? */
577 if (S_ISDIR(st.st_mode)) {
578 errno = EISDIR;
579 return NULL;
583 * Anything else, just open it and try to use it as
584 * a ref
586 fd = open(path, O_RDONLY);
587 if (fd < 0)
588 return NULL;
589 len = read_in_full(fd, buffer, sizeof(buffer)-1);
590 close(fd);
591 if (len < 0)
592 return NULL;
593 while (len && isspace(buffer[len-1]))
594 len--;
595 buffer[len] = '\0';
598 * Is it a symbolic ref?
600 if (prefixcmp(buffer, "ref:"))
601 break;
602 if (flag)
603 *flag |= REF_ISSYMREF;
604 buf = buffer + 4;
605 while (isspace(*buf))
606 buf++;
607 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
608 if (flag)
609 *flag |= REF_ISBROKEN;
610 return NULL;
612 refname = strcpy(refname_buffer, buf);
614 /* Please note that FETCH_HEAD has a second line containing other data. */
615 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
616 if (flag)
617 *flag |= REF_ISBROKEN;
618 return NULL;
620 return refname;
623 char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
625 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
626 return ret ? xstrdup(ret) : NULL;
629 /* The argument to filter_refs */
630 struct ref_filter {
631 const char *pattern;
632 each_ref_fn *fn;
633 void *cb_data;
636 int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
638 if (resolve_ref_unsafe(refname, sha1, reading, flags))
639 return 0;
640 return -1;
643 int read_ref(const char *refname, unsigned char *sha1)
645 return read_ref_full(refname, sha1, 1, NULL);
648 #define DO_FOR_EACH_INCLUDE_BROKEN 01
649 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
650 int flags, void *cb_data, struct ref_entry *entry)
652 if (prefixcmp(entry->name, base))
653 return 0;
655 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
656 if (entry->flag & REF_ISBROKEN)
657 return 0; /* ignore broken refs e.g. dangling symref */
658 if (!has_sha1_file(entry->sha1)) {
659 error("%s does not point to a valid object!", entry->name);
660 return 0;
663 current_ref = entry;
664 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
667 static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
668 void *data)
670 struct ref_filter *filter = (struct ref_filter *)data;
671 if (fnmatch(filter->pattern, refname, 0))
672 return 0;
673 return filter->fn(refname, sha1, flags, filter->cb_data);
676 int peel_ref(const char *refname, unsigned char *sha1)
678 int flag;
679 unsigned char base[20];
680 struct object *o;
682 if (current_ref && (current_ref->name == refname
683 || !strcmp(current_ref->name, refname))) {
684 if (current_ref->flag & REF_KNOWS_PEELED) {
685 hashcpy(sha1, current_ref->peeled);
686 return 0;
688 hashcpy(base, current_ref->sha1);
689 goto fallback;
692 if (read_ref_full(refname, base, 1, &flag))
693 return -1;
695 if ((flag & REF_ISPACKED)) {
696 struct ref_array *array = get_packed_refs(get_ref_cache(NULL));
697 struct ref_entry *r = search_ref_array(array, refname);
699 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
700 hashcpy(sha1, r->peeled);
701 return 0;
705 fallback:
706 o = parse_object(base);
707 if (o && o->type == OBJ_TAG) {
708 o = deref_tag(o, refname, 0);
709 if (o) {
710 hashcpy(sha1, o->sha1);
711 return 0;
714 return -1;
717 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
718 int trim, int flags, void *cb_data)
720 int retval = 0, p = 0, l = 0;
721 struct ref_cache *refs = get_ref_cache(submodule);
722 struct ref_array *packed = get_packed_refs(refs);
723 struct ref_array *loose = get_loose_refs(refs);
725 sort_ref_array(packed);
726 sort_ref_array(loose);
727 while (p < packed->nr && l < loose->nr) {
728 struct ref_entry *entry;
729 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
730 if (!cmp) {
731 p++;
732 continue;
734 if (cmp > 0) {
735 entry = loose->refs[l++];
736 } else {
737 entry = packed->refs[p++];
739 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
740 if (retval)
741 goto end_each;
744 if (l < loose->nr) {
745 p = l;
746 packed = loose;
749 for (; p < packed->nr; p++) {
750 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
751 if (retval)
752 goto end_each;
755 end_each:
756 current_ref = NULL;
757 return retval;
761 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
763 unsigned char sha1[20];
764 int flag;
766 if (submodule) {
767 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
768 return fn("HEAD", sha1, 0, cb_data);
770 return 0;
773 if (!read_ref_full("HEAD", sha1, 1, &flag))
774 return fn("HEAD", sha1, flag, cb_data);
776 return 0;
779 int head_ref(each_ref_fn fn, void *cb_data)
781 return do_head_ref(NULL, fn, cb_data);
784 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
786 return do_head_ref(submodule, fn, cb_data);
789 int for_each_ref(each_ref_fn fn, void *cb_data)
791 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
794 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
796 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
799 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
801 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
804 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
805 each_ref_fn fn, void *cb_data)
807 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
810 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
812 return for_each_ref_in("refs/tags/", fn, cb_data);
815 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
817 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
820 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
822 return for_each_ref_in("refs/heads/", fn, cb_data);
825 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
827 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
830 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
832 return for_each_ref_in("refs/remotes/", fn, cb_data);
835 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
837 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
840 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
842 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
845 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
847 struct strbuf buf = STRBUF_INIT;
848 int ret = 0;
849 unsigned char sha1[20];
850 int flag;
852 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
853 if (!read_ref_full(buf.buf, sha1, 1, &flag))
854 ret = fn(buf.buf, sha1, flag, cb_data);
855 strbuf_release(&buf);
857 return ret;
860 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
862 struct strbuf buf = STRBUF_INIT;
863 int ret;
864 strbuf_addf(&buf, "%srefs/", get_git_namespace());
865 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
866 strbuf_release(&buf);
867 return ret;
870 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
871 const char *prefix, void *cb_data)
873 struct strbuf real_pattern = STRBUF_INIT;
874 struct ref_filter filter;
875 int ret;
877 if (!prefix && prefixcmp(pattern, "refs/"))
878 strbuf_addstr(&real_pattern, "refs/");
879 else if (prefix)
880 strbuf_addstr(&real_pattern, prefix);
881 strbuf_addstr(&real_pattern, pattern);
883 if (!has_glob_specials(pattern)) {
884 /* Append implied '/' '*' if not present. */
885 if (real_pattern.buf[real_pattern.len - 1] != '/')
886 strbuf_addch(&real_pattern, '/');
887 /* No need to check for '*', there is none. */
888 strbuf_addch(&real_pattern, '*');
891 filter.pattern = real_pattern.buf;
892 filter.fn = fn;
893 filter.cb_data = cb_data;
894 ret = for_each_ref(filter_refs, &filter);
896 strbuf_release(&real_pattern);
897 return ret;
900 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
902 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
905 int for_each_rawref(each_ref_fn fn, void *cb_data)
907 return do_for_each_ref(NULL, "", fn, 0,
908 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
912 * Make sure "ref" is something reasonable to have under ".git/refs/";
913 * We do not like it if:
915 * - any path component of it begins with ".", or
916 * - it has double dots "..", or
917 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
918 * - it ends with a "/".
919 * - it ends with ".lock"
920 * - it contains a "\" (backslash)
923 /* Return true iff ch is not allowed in reference names. */
924 static inline int bad_ref_char(int ch)
926 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
927 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
928 return 1;
929 /* 2.13 Pattern Matching Notation */
930 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
931 return 1;
932 return 0;
936 * Try to read one refname component from the front of refname. Return
937 * the length of the component found, or -1 if the component is not
938 * legal.
940 static int check_refname_component(const char *refname, int flags)
942 const char *cp;
943 char last = '\0';
945 for (cp = refname; ; cp++) {
946 char ch = *cp;
947 if (ch == '\0' || ch == '/')
948 break;
949 if (bad_ref_char(ch))
950 return -1; /* Illegal character in refname. */
951 if (last == '.' && ch == '.')
952 return -1; /* Refname contains "..". */
953 if (last == '@' && ch == '{')
954 return -1; /* Refname contains "@{". */
955 last = ch;
957 if (cp == refname)
958 return -1; /* Component has zero length. */
959 if (refname[0] == '.') {
960 if (!(flags & REFNAME_DOT_COMPONENT))
961 return -1; /* Component starts with '.'. */
963 * Even if leading dots are allowed, don't allow "."
964 * as a component (".." is prevented by a rule above).
966 if (refname[1] == '\0')
967 return -1; /* Component equals ".". */
969 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
970 return -1; /* Refname ends with ".lock". */
971 return cp - refname;
974 int check_refname_format(const char *refname, int flags)
976 int component_len, component_count = 0;
978 while (1) {
979 /* We are at the start of a path component. */
980 component_len = check_refname_component(refname, flags);
981 if (component_len < 0) {
982 if ((flags & REFNAME_REFSPEC_PATTERN) &&
983 refname[0] == '*' &&
984 (refname[1] == '\0' || refname[1] == '/')) {
985 /* Accept one wildcard as a full refname component. */
986 flags &= ~REFNAME_REFSPEC_PATTERN;
987 component_len = 1;
988 } else {
989 return -1;
992 component_count++;
993 if (refname[component_len] == '\0')
994 break;
995 /* Skip to next component. */
996 refname += component_len + 1;
999 if (refname[component_len - 1] == '.')
1000 return -1; /* Refname ends with '.'. */
1001 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
1002 return -1; /* Refname has only one component. */
1003 return 0;
1006 const char *prettify_refname(const char *name)
1008 return name + (
1009 !prefixcmp(name, "refs/heads/") ? 11 :
1010 !prefixcmp(name, "refs/tags/") ? 10 :
1011 !prefixcmp(name, "refs/remotes/") ? 13 :
1015 const char *ref_rev_parse_rules[] = {
1016 "%.*s",
1017 "refs/%.*s",
1018 "refs/tags/%.*s",
1019 "refs/heads/%.*s",
1020 "refs/remotes/%.*s",
1021 "refs/remotes/%.*s/HEAD",
1022 NULL
1025 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1027 const char **p;
1028 const int abbrev_name_len = strlen(abbrev_name);
1030 for (p = rules; *p; p++) {
1031 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1032 return 1;
1036 return 0;
1039 static struct ref_lock *verify_lock(struct ref_lock *lock,
1040 const unsigned char *old_sha1, int mustexist)
1042 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1043 error("Can't verify ref %s", lock->ref_name);
1044 unlock_ref(lock);
1045 return NULL;
1047 if (hashcmp(lock->old_sha1, old_sha1)) {
1048 error("Ref %s is at %s but expected %s", lock->ref_name,
1049 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1050 unlock_ref(lock);
1051 return NULL;
1053 return lock;
1056 static int remove_empty_directories(const char *file)
1058 /* we want to create a file but there is a directory there;
1059 * if that is an empty directory (or a directory that contains
1060 * only empty directories), remove them.
1062 struct strbuf path;
1063 int result;
1065 strbuf_init(&path, 20);
1066 strbuf_addstr(&path, file);
1068 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1070 strbuf_release(&path);
1072 return result;
1076 * Return true iff a reference named refname could be created without
1077 * conflicting with the name of an existing reference. If oldrefname
1078 * is non-NULL, ignore potential conflicts with oldrefname (e.g.,
1079 * because oldrefname is scheduled for deletion in the same
1080 * operation).
1082 static int is_refname_available(const char *refname, const char *oldrefname,
1083 struct ref_array *array)
1085 int i, namlen = strlen(refname); /* e.g. 'foo/bar' */
1086 for (i = 0; i < array->nr; i++ ) {
1087 struct ref_entry *entry = array->refs[i];
1088 /* entry->name could be 'foo' or 'foo/bar/baz' */
1089 if (!oldrefname || strcmp(oldrefname, entry->name)) {
1090 int len = strlen(entry->name);
1091 int cmplen = (namlen < len) ? namlen : len;
1092 const char *lead = (namlen < len) ? entry->name : refname;
1093 if (!strncmp(refname, entry->name, cmplen) &&
1094 lead[cmplen] == '/') {
1095 error("'%s' exists; cannot create '%s'",
1096 entry->name, refname);
1097 return 0;
1101 return 1;
1105 * *string and *len will only be substituted, and *string returned (for
1106 * later free()ing) if the string passed in is a magic short-hand form
1107 * to name a branch.
1109 static char *substitute_branch_name(const char **string, int *len)
1111 struct strbuf buf = STRBUF_INIT;
1112 int ret = interpret_branch_name(*string, &buf);
1114 if (ret == *len) {
1115 size_t size;
1116 *string = strbuf_detach(&buf, &size);
1117 *len = size;
1118 return (char *)*string;
1121 return NULL;
1124 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1126 char *last_branch = substitute_branch_name(&str, &len);
1127 const char **p, *r;
1128 int refs_found = 0;
1130 *ref = NULL;
1131 for (p = ref_rev_parse_rules; *p; p++) {
1132 char fullref[PATH_MAX];
1133 unsigned char sha1_from_ref[20];
1134 unsigned char *this_result;
1135 int flag;
1137 this_result = refs_found ? sha1_from_ref : sha1;
1138 mksnpath(fullref, sizeof(fullref), *p, len, str);
1139 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
1140 if (r) {
1141 if (!refs_found++)
1142 *ref = xstrdup(r);
1143 if (!warn_ambiguous_refs)
1144 break;
1145 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1146 warning("ignoring dangling symref %s.", fullref);
1147 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1148 warning("ignoring broken ref %s.", fullref);
1151 free(last_branch);
1152 return refs_found;
1155 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1157 char *last_branch = substitute_branch_name(&str, &len);
1158 const char **p;
1159 int logs_found = 0;
1161 *log = NULL;
1162 for (p = ref_rev_parse_rules; *p; p++) {
1163 struct stat st;
1164 unsigned char hash[20];
1165 char path[PATH_MAX];
1166 const char *ref, *it;
1168 mksnpath(path, sizeof(path), *p, len, str);
1169 ref = resolve_ref_unsafe(path, hash, 1, NULL);
1170 if (!ref)
1171 continue;
1172 if (!stat(git_path("logs/%s", path), &st) &&
1173 S_ISREG(st.st_mode))
1174 it = path;
1175 else if (strcmp(ref, path) &&
1176 !stat(git_path("logs/%s", ref), &st) &&
1177 S_ISREG(st.st_mode))
1178 it = ref;
1179 else
1180 continue;
1181 if (!logs_found++) {
1182 *log = xstrdup(it);
1183 hashcpy(sha1, hash);
1185 if (!warn_ambiguous_refs)
1186 break;
1188 free(last_branch);
1189 return logs_found;
1192 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1193 const unsigned char *old_sha1,
1194 int flags, int *type_p)
1196 char *ref_file;
1197 const char *orig_refname = refname;
1198 struct ref_lock *lock;
1199 int last_errno = 0;
1200 int type, lflags;
1201 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1202 int missing = 0;
1204 lock = xcalloc(1, sizeof(struct ref_lock));
1205 lock->lock_fd = -1;
1207 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
1208 if (!refname && errno == EISDIR) {
1209 /* we are trying to lock foo but we used to
1210 * have foo/bar which now does not exist;
1211 * it is normal for the empty directory 'foo'
1212 * to remain.
1214 ref_file = git_path("%s", orig_refname);
1215 if (remove_empty_directories(ref_file)) {
1216 last_errno = errno;
1217 error("there are still refs under '%s'", orig_refname);
1218 goto error_return;
1220 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
1222 if (type_p)
1223 *type_p = type;
1224 if (!refname) {
1225 last_errno = errno;
1226 error("unable to resolve reference %s: %s",
1227 orig_refname, strerror(errno));
1228 goto error_return;
1230 missing = is_null_sha1(lock->old_sha1);
1231 /* When the ref did not exist and we are creating it,
1232 * make sure there is no existing ref that is packed
1233 * whose name begins with our refname, nor a ref whose
1234 * name is a proper prefix of our refname.
1236 if (missing &&
1237 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
1238 last_errno = ENOTDIR;
1239 goto error_return;
1242 lock->lk = xcalloc(1, sizeof(struct lock_file));
1244 lflags = LOCK_DIE_ON_ERROR;
1245 if (flags & REF_NODEREF) {
1246 refname = orig_refname;
1247 lflags |= LOCK_NODEREF;
1249 lock->ref_name = xstrdup(refname);
1250 lock->orig_ref_name = xstrdup(orig_refname);
1251 ref_file = git_path("%s", refname);
1252 if (missing)
1253 lock->force_write = 1;
1254 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1255 lock->force_write = 1;
1257 if (safe_create_leading_directories(ref_file)) {
1258 last_errno = errno;
1259 error("unable to create directory for %s", ref_file);
1260 goto error_return;
1263 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1264 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1266 error_return:
1267 unlock_ref(lock);
1268 errno = last_errno;
1269 return NULL;
1272 struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
1274 char refpath[PATH_MAX];
1275 if (check_refname_format(refname, 0))
1276 return NULL;
1277 strcpy(refpath, mkpath("refs/%s", refname));
1278 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1281 struct ref_lock *lock_any_ref_for_update(const char *refname,
1282 const unsigned char *old_sha1, int flags)
1284 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1285 return NULL;
1286 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
1289 static struct lock_file packlock;
1291 static int repack_without_ref(const char *refname)
1293 struct ref_array *packed;
1294 int fd, i;
1296 packed = get_packed_refs(get_ref_cache(NULL));
1297 if (search_ref_array(packed, refname) == NULL)
1298 return 0;
1299 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1300 if (fd < 0) {
1301 unable_to_lock_error(git_path("packed-refs"), errno);
1302 return error("cannot delete '%s' from packed refs", refname);
1305 for (i = 0; i < packed->nr; i++) {
1306 char line[PATH_MAX + 100];
1307 int len;
1308 struct ref_entry *ref = packed->refs[i];
1310 if (!strcmp(refname, ref->name))
1311 continue;
1312 len = snprintf(line, sizeof(line), "%s %s\n",
1313 sha1_to_hex(ref->sha1), ref->name);
1314 /* this should not happen but just being defensive */
1315 if (len > sizeof(line))
1316 die("too long a refname '%s'", ref->name);
1317 write_or_die(fd, line, len);
1319 return commit_lock_file(&packlock);
1322 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1324 struct ref_lock *lock;
1325 int err, i = 0, ret = 0, flag = 0;
1327 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1328 if (!lock)
1329 return 1;
1330 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1331 /* loose */
1332 const char *path;
1334 if (!(delopt & REF_NODEREF)) {
1335 i = strlen(lock->lk->filename) - 5; /* .lock */
1336 lock->lk->filename[i] = 0;
1337 path = lock->lk->filename;
1338 } else {
1339 path = git_path("%s", refname);
1341 err = unlink_or_warn(path);
1342 if (err && errno != ENOENT)
1343 ret = 1;
1345 if (!(delopt & REF_NODEREF))
1346 lock->lk->filename[i] = '.';
1348 /* removing the loose one could have resurrected an earlier
1349 * packed one. Also, if it was not loose we need to repack
1350 * without it.
1352 ret |= repack_without_ref(refname);
1354 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1355 invalidate_ref_cache(NULL);
1356 unlock_ref(lock);
1357 return ret;
1361 * People using contrib's git-new-workdir have .git/logs/refs ->
1362 * /some/other/path/.git/logs/refs, and that may live on another device.
1364 * IOW, to avoid cross device rename errors, the temporary renamed log must
1365 * live into logs/refs.
1367 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1369 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
1371 unsigned char sha1[20], orig_sha1[20];
1372 int flag = 0, logmoved = 0;
1373 struct ref_lock *lock;
1374 struct stat loginfo;
1375 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
1376 const char *symref = NULL;
1377 struct ref_cache *refs = get_ref_cache(NULL);
1379 if (log && S_ISLNK(loginfo.st_mode))
1380 return error("reflog for %s is a symlink", oldrefname);
1382 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
1383 if (flag & REF_ISSYMREF)
1384 return error("refname %s is a symbolic ref, renaming it is not supported",
1385 oldrefname);
1386 if (!symref)
1387 return error("refname %s not found", oldrefname);
1389 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
1390 return 1;
1392 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
1393 return 1;
1395 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
1396 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1397 oldrefname, strerror(errno));
1399 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1400 error("unable to delete old %s", oldrefname);
1401 goto rollback;
1404 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1405 delete_ref(newrefname, sha1, REF_NODEREF)) {
1406 if (errno==EISDIR) {
1407 if (remove_empty_directories(git_path("%s", newrefname))) {
1408 error("Directory not empty: %s", newrefname);
1409 goto rollback;
1411 } else {
1412 error("unable to delete existing %s", newrefname);
1413 goto rollback;
1417 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1418 error("unable to create directory for %s", newrefname);
1419 goto rollback;
1422 retry:
1423 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
1424 if (errno==EISDIR || errno==ENOTDIR) {
1426 * rename(a, b) when b is an existing
1427 * directory ought to result in ISDIR, but
1428 * Solaris 5.8 gives ENOTDIR. Sheesh.
1430 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1431 error("Directory not empty: logs/%s", newrefname);
1432 goto rollback;
1434 goto retry;
1435 } else {
1436 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1437 newrefname, strerror(errno));
1438 goto rollback;
1441 logmoved = log;
1443 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
1444 if (!lock) {
1445 error("unable to lock %s for update", newrefname);
1446 goto rollback;
1448 lock->force_write = 1;
1449 hashcpy(lock->old_sha1, orig_sha1);
1450 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1451 error("unable to write current sha1 into %s", newrefname);
1452 goto rollback;
1455 return 0;
1457 rollback:
1458 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
1459 if (!lock) {
1460 error("unable to lock %s for rollback", oldrefname);
1461 goto rollbacklog;
1464 lock->force_write = 1;
1465 flag = log_all_ref_updates;
1466 log_all_ref_updates = 0;
1467 if (write_ref_sha1(lock, orig_sha1, NULL))
1468 error("unable to write current sha1 into %s", oldrefname);
1469 log_all_ref_updates = flag;
1471 rollbacklog:
1472 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
1473 error("unable to restore logfile %s from %s: %s",
1474 oldrefname, newrefname, strerror(errno));
1475 if (!logmoved && log &&
1476 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
1477 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1478 oldrefname, strerror(errno));
1480 return 1;
1483 int close_ref(struct ref_lock *lock)
1485 if (close_lock_file(lock->lk))
1486 return -1;
1487 lock->lock_fd = -1;
1488 return 0;
1491 int commit_ref(struct ref_lock *lock)
1493 if (commit_lock_file(lock->lk))
1494 return -1;
1495 lock->lock_fd = -1;
1496 return 0;
1499 void unlock_ref(struct ref_lock *lock)
1501 /* Do not free lock->lk -- atexit() still looks at them */
1502 if (lock->lk)
1503 rollback_lock_file(lock->lk);
1504 free(lock->ref_name);
1505 free(lock->orig_ref_name);
1506 free(lock);
1510 * copy the reflog message msg to buf, which has been allocated sufficiently
1511 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1512 * because reflog file is one line per entry.
1514 static int copy_msg(char *buf, const char *msg)
1516 char *cp = buf;
1517 char c;
1518 int wasspace = 1;
1520 *cp++ = '\t';
1521 while ((c = *msg++)) {
1522 if (wasspace && isspace(c))
1523 continue;
1524 wasspace = isspace(c);
1525 if (wasspace)
1526 c = ' ';
1527 *cp++ = c;
1529 while (buf < cp && isspace(cp[-1]))
1530 cp--;
1531 *cp++ = '\n';
1532 return cp - buf;
1535 int log_ref_setup(const char *refname, char *logfile, int bufsize)
1537 int logfd, oflags = O_APPEND | O_WRONLY;
1539 git_snpath(logfile, bufsize, "logs/%s", refname);
1540 if (log_all_ref_updates &&
1541 (!prefixcmp(refname, "refs/heads/") ||
1542 !prefixcmp(refname, "refs/remotes/") ||
1543 !prefixcmp(refname, "refs/notes/") ||
1544 !strcmp(refname, "HEAD"))) {
1545 if (safe_create_leading_directories(logfile) < 0)
1546 return error("unable to create directory for %s",
1547 logfile);
1548 oflags |= O_CREAT;
1551 logfd = open(logfile, oflags, 0666);
1552 if (logfd < 0) {
1553 if (!(oflags & O_CREAT) && errno == ENOENT)
1554 return 0;
1556 if ((oflags & O_CREAT) && errno == EISDIR) {
1557 if (remove_empty_directories(logfile)) {
1558 return error("There are still logs under '%s'",
1559 logfile);
1561 logfd = open(logfile, oflags, 0666);
1564 if (logfd < 0)
1565 return error("Unable to append to %s: %s",
1566 logfile, strerror(errno));
1569 adjust_shared_perm(logfile);
1570 close(logfd);
1571 return 0;
1574 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
1575 const unsigned char *new_sha1, const char *msg)
1577 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1578 unsigned maxlen, len;
1579 int msglen;
1580 char log_file[PATH_MAX];
1581 char *logrec;
1582 const char *committer;
1584 if (log_all_ref_updates < 0)
1585 log_all_ref_updates = !is_bare_repository();
1587 result = log_ref_setup(refname, log_file, sizeof(log_file));
1588 if (result)
1589 return result;
1591 logfd = open(log_file, oflags);
1592 if (logfd < 0)
1593 return 0;
1594 msglen = msg ? strlen(msg) : 0;
1595 committer = git_committer_info(0);
1596 maxlen = strlen(committer) + msglen + 100;
1597 logrec = xmalloc(maxlen);
1598 len = sprintf(logrec, "%s %s %s\n",
1599 sha1_to_hex(old_sha1),
1600 sha1_to_hex(new_sha1),
1601 committer);
1602 if (msglen)
1603 len += copy_msg(logrec + len - 1, msg) - 1;
1604 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1605 free(logrec);
1606 if (close(logfd) != 0 || written != len)
1607 return error("Unable to append to %s", log_file);
1608 return 0;
1611 static int is_branch(const char *refname)
1613 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1616 int write_ref_sha1(struct ref_lock *lock,
1617 const unsigned char *sha1, const char *logmsg)
1619 static char term = '\n';
1620 struct object *o;
1622 if (!lock)
1623 return -1;
1624 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1625 unlock_ref(lock);
1626 return 0;
1628 o = parse_object(sha1);
1629 if (!o) {
1630 error("Trying to write ref %s with nonexistent object %s",
1631 lock->ref_name, sha1_to_hex(sha1));
1632 unlock_ref(lock);
1633 return -1;
1635 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1636 error("Trying to write non-commit object %s to branch %s",
1637 sha1_to_hex(sha1), lock->ref_name);
1638 unlock_ref(lock);
1639 return -1;
1641 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1642 write_in_full(lock->lock_fd, &term, 1) != 1
1643 || close_ref(lock) < 0) {
1644 error("Couldn't write %s", lock->lk->filename);
1645 unlock_ref(lock);
1646 return -1;
1648 clear_loose_ref_cache(get_ref_cache(NULL));
1649 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1650 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1651 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1652 unlock_ref(lock);
1653 return -1;
1655 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1657 * Special hack: If a branch is updated directly and HEAD
1658 * points to it (may happen on the remote side of a push
1659 * for example) then logically the HEAD reflog should be
1660 * updated too.
1661 * A generic solution implies reverse symref information,
1662 * but finding all symrefs pointing to the given branch
1663 * would be rather costly for this rare event (the direct
1664 * update of a branch) to be worth it. So let's cheat and
1665 * check with HEAD only which should cover 99% of all usage
1666 * scenarios (even 100% of the default ones).
1668 unsigned char head_sha1[20];
1669 int head_flag;
1670 const char *head_ref;
1671 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
1672 if (head_ref && (head_flag & REF_ISSYMREF) &&
1673 !strcmp(head_ref, lock->ref_name))
1674 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1676 if (commit_ref(lock)) {
1677 error("Couldn't set %s", lock->ref_name);
1678 unlock_ref(lock);
1679 return -1;
1681 unlock_ref(lock);
1682 return 0;
1685 int create_symref(const char *ref_target, const char *refs_heads_master,
1686 const char *logmsg)
1688 const char *lockpath;
1689 char ref[1000];
1690 int fd, len, written;
1691 char *git_HEAD = git_pathdup("%s", ref_target);
1692 unsigned char old_sha1[20], new_sha1[20];
1694 if (logmsg && read_ref(ref_target, old_sha1))
1695 hashclr(old_sha1);
1697 if (safe_create_leading_directories(git_HEAD) < 0)
1698 return error("unable to create directory for %s", git_HEAD);
1700 #ifndef NO_SYMLINK_HEAD
1701 if (prefer_symlink_refs) {
1702 unlink(git_HEAD);
1703 if (!symlink(refs_heads_master, git_HEAD))
1704 goto done;
1705 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1707 #endif
1709 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1710 if (sizeof(ref) <= len) {
1711 error("refname too long: %s", refs_heads_master);
1712 goto error_free_return;
1714 lockpath = mkpath("%s.lock", git_HEAD);
1715 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1716 if (fd < 0) {
1717 error("Unable to open %s for writing", lockpath);
1718 goto error_free_return;
1720 written = write_in_full(fd, ref, len);
1721 if (close(fd) != 0 || written != len) {
1722 error("Unable to write to %s", lockpath);
1723 goto error_unlink_return;
1725 if (rename(lockpath, git_HEAD) < 0) {
1726 error("Unable to create %s", git_HEAD);
1727 goto error_unlink_return;
1729 if (adjust_shared_perm(git_HEAD)) {
1730 error("Unable to fix permissions on %s", lockpath);
1731 error_unlink_return:
1732 unlink_or_warn(lockpath);
1733 error_free_return:
1734 free(git_HEAD);
1735 return -1;
1738 #ifndef NO_SYMLINK_HEAD
1739 done:
1740 #endif
1741 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1742 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1744 free(git_HEAD);
1745 return 0;
1748 static char *ref_msg(const char *line, const char *endp)
1750 const char *ep;
1751 line += 82;
1752 ep = memchr(line, '\n', endp - line);
1753 if (!ep)
1754 ep = endp;
1755 return xmemdupz(line, ep - line);
1758 int read_ref_at(const char *refname, unsigned long at_time, int cnt,
1759 unsigned char *sha1, char **msg,
1760 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1762 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1763 char *tz_c;
1764 int logfd, tz, reccnt = 0;
1765 struct stat st;
1766 unsigned long date;
1767 unsigned char logged_sha1[20];
1768 void *log_mapped;
1769 size_t mapsz;
1771 logfile = git_path("logs/%s", refname);
1772 logfd = open(logfile, O_RDONLY, 0);
1773 if (logfd < 0)
1774 die_errno("Unable to read log '%s'", logfile);
1775 fstat(logfd, &st);
1776 if (!st.st_size)
1777 die("Log %s is empty.", logfile);
1778 mapsz = xsize_t(st.st_size);
1779 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1780 logdata = log_mapped;
1781 close(logfd);
1783 lastrec = NULL;
1784 rec = logend = logdata + st.st_size;
1785 while (logdata < rec) {
1786 reccnt++;
1787 if (logdata < rec && *(rec-1) == '\n')
1788 rec--;
1789 lastgt = NULL;
1790 while (logdata < rec && *(rec-1) != '\n') {
1791 rec--;
1792 if (*rec == '>')
1793 lastgt = rec;
1795 if (!lastgt)
1796 die("Log %s is corrupt.", logfile);
1797 date = strtoul(lastgt + 1, &tz_c, 10);
1798 if (date <= at_time || cnt == 0) {
1799 tz = strtoul(tz_c, NULL, 10);
1800 if (msg)
1801 *msg = ref_msg(rec, logend);
1802 if (cutoff_time)
1803 *cutoff_time = date;
1804 if (cutoff_tz)
1805 *cutoff_tz = tz;
1806 if (cutoff_cnt)
1807 *cutoff_cnt = reccnt - 1;
1808 if (lastrec) {
1809 if (get_sha1_hex(lastrec, logged_sha1))
1810 die("Log %s is corrupt.", logfile);
1811 if (get_sha1_hex(rec + 41, sha1))
1812 die("Log %s is corrupt.", logfile);
1813 if (hashcmp(logged_sha1, sha1)) {
1814 warning("Log %s has gap after %s.",
1815 logfile, show_date(date, tz, DATE_RFC2822));
1818 else if (date == at_time) {
1819 if (get_sha1_hex(rec + 41, sha1))
1820 die("Log %s is corrupt.", logfile);
1822 else {
1823 if (get_sha1_hex(rec + 41, logged_sha1))
1824 die("Log %s is corrupt.", logfile);
1825 if (hashcmp(logged_sha1, sha1)) {
1826 warning("Log %s unexpectedly ended on %s.",
1827 logfile, show_date(date, tz, DATE_RFC2822));
1830 munmap(log_mapped, mapsz);
1831 return 0;
1833 lastrec = rec;
1834 if (cnt > 0)
1835 cnt--;
1838 rec = logdata;
1839 while (rec < logend && *rec != '>' && *rec != '\n')
1840 rec++;
1841 if (rec == logend || *rec == '\n')
1842 die("Log %s is corrupt.", logfile);
1843 date = strtoul(rec + 1, &tz_c, 10);
1844 tz = strtoul(tz_c, NULL, 10);
1845 if (get_sha1_hex(logdata, sha1))
1846 die("Log %s is corrupt.", logfile);
1847 if (is_null_sha1(sha1)) {
1848 if (get_sha1_hex(logdata + 41, sha1))
1849 die("Log %s is corrupt.", logfile);
1851 if (msg)
1852 *msg = ref_msg(logdata, logend);
1853 munmap(log_mapped, mapsz);
1855 if (cutoff_time)
1856 *cutoff_time = date;
1857 if (cutoff_tz)
1858 *cutoff_tz = tz;
1859 if (cutoff_cnt)
1860 *cutoff_cnt = reccnt;
1861 return 1;
1864 int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
1866 const char *logfile;
1867 FILE *logfp;
1868 struct strbuf sb = STRBUF_INIT;
1869 int ret = 0;
1871 logfile = git_path("logs/%s", refname);
1872 logfp = fopen(logfile, "r");
1873 if (!logfp)
1874 return -1;
1876 if (ofs) {
1877 struct stat statbuf;
1878 if (fstat(fileno(logfp), &statbuf) ||
1879 statbuf.st_size < ofs ||
1880 fseek(logfp, -ofs, SEEK_END) ||
1881 strbuf_getwholeline(&sb, logfp, '\n')) {
1882 fclose(logfp);
1883 strbuf_release(&sb);
1884 return -1;
1888 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1889 unsigned char osha1[20], nsha1[20];
1890 char *email_end, *message;
1891 unsigned long timestamp;
1892 int tz;
1894 /* old SP new SP name <email> SP time TAB msg LF */
1895 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1896 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1897 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1898 !(email_end = strchr(sb.buf + 82, '>')) ||
1899 email_end[1] != ' ' ||
1900 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1901 !message || message[0] != ' ' ||
1902 (message[1] != '+' && message[1] != '-') ||
1903 !isdigit(message[2]) || !isdigit(message[3]) ||
1904 !isdigit(message[4]) || !isdigit(message[5]))
1905 continue; /* corrupt? */
1906 email_end[1] = '\0';
1907 tz = strtol(message + 1, NULL, 10);
1908 if (message[6] != '\t')
1909 message += 6;
1910 else
1911 message += 7;
1912 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1913 cb_data);
1914 if (ret)
1915 break;
1917 fclose(logfp);
1918 strbuf_release(&sb);
1919 return ret;
1922 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
1924 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
1927 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1929 DIR *dir = opendir(git_path("logs/%s", base));
1930 int retval = 0;
1932 if (dir) {
1933 struct dirent *de;
1934 int baselen = strlen(base);
1935 char *log = xmalloc(baselen + 257);
1937 memcpy(log, base, baselen);
1938 if (baselen && base[baselen-1] != '/')
1939 log[baselen++] = '/';
1941 while ((de = readdir(dir)) != NULL) {
1942 struct stat st;
1943 int namelen;
1945 if (de->d_name[0] == '.')
1946 continue;
1947 namelen = strlen(de->d_name);
1948 if (namelen > 255)
1949 continue;
1950 if (has_extension(de->d_name, ".lock"))
1951 continue;
1952 memcpy(log + baselen, de->d_name, namelen+1);
1953 if (stat(git_path("logs/%s", log), &st) < 0)
1954 continue;
1955 if (S_ISDIR(st.st_mode)) {
1956 retval = do_for_each_reflog(log, fn, cb_data);
1957 } else {
1958 unsigned char sha1[20];
1959 if (read_ref_full(log, sha1, 0, NULL))
1960 retval = error("bad ref for %s", log);
1961 else
1962 retval = fn(log, sha1, 0, cb_data);
1964 if (retval)
1965 break;
1967 free(log);
1968 closedir(dir);
1970 else if (*base)
1971 return errno;
1972 return retval;
1975 int for_each_reflog(each_ref_fn fn, void *cb_data)
1977 return do_for_each_reflog("", fn, cb_data);
1980 int update_ref(const char *action, const char *refname,
1981 const unsigned char *sha1, const unsigned char *oldval,
1982 int flags, enum action_on_err onerr)
1984 static struct ref_lock *lock;
1985 lock = lock_any_ref_for_update(refname, oldval, flags);
1986 if (!lock) {
1987 const char *str = "Cannot lock the ref '%s'.";
1988 switch (onerr) {
1989 case MSG_ON_ERR: error(str, refname); break;
1990 case DIE_ON_ERR: die(str, refname); break;
1991 case QUIET_ON_ERR: break;
1993 return 1;
1995 if (write_ref_sha1(lock, sha1, action) < 0) {
1996 const char *str = "Cannot update the ref '%s'.";
1997 switch (onerr) {
1998 case MSG_ON_ERR: error(str, refname); break;
1999 case DIE_ON_ERR: die(str, refname); break;
2000 case QUIET_ON_ERR: break;
2002 return 1;
2004 return 0;
2007 int ref_exists(const char *refname)
2009 unsigned char sha1[20];
2010 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
2013 struct ref *find_ref_by_name(const struct ref *list, const char *name)
2015 for ( ; list; list = list->next)
2016 if (!strcmp(list->name, name))
2017 return (struct ref *)list;
2018 return NULL;
2022 * generate a format suitable for scanf from a ref_rev_parse_rules
2023 * rule, that is replace the "%.*s" spec with a "%s" spec
2025 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2027 char *spec;
2029 spec = strstr(rule, "%.*s");
2030 if (!spec || strstr(spec + 4, "%.*s"))
2031 die("invalid rule in ref_rev_parse_rules: %s", rule);
2033 /* copy all until spec */
2034 strncpy(scanf_fmt, rule, spec - rule);
2035 scanf_fmt[spec - rule] = '\0';
2036 /* copy new spec */
2037 strcat(scanf_fmt, "%s");
2038 /* copy remaining rule */
2039 strcat(scanf_fmt, spec + 4);
2041 return;
2044 char *shorten_unambiguous_ref(const char *refname, int strict)
2046 int i;
2047 static char **scanf_fmts;
2048 static int nr_rules;
2049 char *short_name;
2051 /* pre generate scanf formats from ref_rev_parse_rules[] */
2052 if (!nr_rules) {
2053 size_t total_len = 0;
2055 /* the rule list is NULL terminated, count them first */
2056 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2057 /* no +1 because strlen("%s") < strlen("%.*s") */
2058 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2060 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2062 total_len = 0;
2063 for (i = 0; i < nr_rules; i++) {
2064 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2065 + total_len;
2066 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2067 total_len += strlen(ref_rev_parse_rules[i]);
2071 /* bail out if there are no rules */
2072 if (!nr_rules)
2073 return xstrdup(refname);
2075 /* buffer for scanf result, at most refname must fit */
2076 short_name = xstrdup(refname);
2078 /* skip first rule, it will always match */
2079 for (i = nr_rules - 1; i > 0 ; --i) {
2080 int j;
2081 int rules_to_fail = i;
2082 int short_name_len;
2084 if (1 != sscanf(refname, scanf_fmts[i], short_name))
2085 continue;
2087 short_name_len = strlen(short_name);
2090 * in strict mode, all (except the matched one) rules
2091 * must fail to resolve to a valid non-ambiguous ref
2093 if (strict)
2094 rules_to_fail = nr_rules;
2097 * check if the short name resolves to a valid ref,
2098 * but use only rules prior to the matched one
2100 for (j = 0; j < rules_to_fail; j++) {
2101 const char *rule = ref_rev_parse_rules[j];
2102 char refname[PATH_MAX];
2104 /* skip matched rule */
2105 if (i == j)
2106 continue;
2109 * the short name is ambiguous, if it resolves
2110 * (with this previous rule) to a valid ref
2111 * read_ref() returns 0 on success
2113 mksnpath(refname, sizeof(refname),
2114 rule, short_name_len, short_name);
2115 if (ref_exists(refname))
2116 break;
2120 * short name is non-ambiguous if all previous rules
2121 * haven't resolved to a valid ref
2123 if (j == rules_to_fail)
2124 return short_name;
2127 free(short_name);
2128 return xstrdup(refname);