Merge branch 'md/smtp-tls-hello-again'
[alt-git.git] / refs.c
blobcab4394ad180b5daf02889fea523fa54abf0560f
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 free(b);
100 continue;
102 i++;
103 array->refs[i] = array->refs[j];
105 array->nr = i + 1;
108 static struct ref_entry *search_ref_array(struct ref_array *array, const char *name)
110 struct ref_entry *e, **r;
111 int len;
113 if (name == NULL)
114 return NULL;
116 if (!array->nr)
117 return NULL;
119 len = strlen(name) + 1;
120 e = xmalloc(sizeof(struct ref_entry) + len);
121 memcpy(e->name, name, len);
123 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
125 free(e);
127 if (r == NULL)
128 return NULL;
130 return *r;
134 * Future: need to be in "struct repository"
135 * when doing a full libification.
137 static struct cached_refs {
138 struct cached_refs *next;
139 char did_loose;
140 char did_packed;
141 struct ref_array loose;
142 struct ref_array packed;
143 /* The submodule name, or "" for the main repo. */
144 char name[FLEX_ARRAY];
145 } *cached_refs;
147 static struct ref_entry *current_ref;
149 static struct ref_array extra_refs;
151 static void free_ref_array(struct ref_array *array)
153 int i;
154 for (i = 0; i < array->nr; i++)
155 free(array->refs[i]);
156 free(array->refs);
157 array->nr = array->alloc = 0;
158 array->refs = NULL;
161 static void clear_cached_refs(struct cached_refs *ca)
163 if (ca->did_loose)
164 free_ref_array(&ca->loose);
165 if (ca->did_packed)
166 free_ref_array(&ca->packed);
167 ca->did_loose = ca->did_packed = 0;
170 static struct cached_refs *create_cached_refs(const char *submodule)
172 int len;
173 struct cached_refs *refs;
174 if (!submodule)
175 submodule = "";
176 len = strlen(submodule) + 1;
177 refs = xcalloc(1, sizeof(struct cached_refs) + len);
178 memcpy(refs->name, submodule, len);
179 return refs;
183 * Return a pointer to a cached_refs for the specified submodule. For
184 * the main repository, use submodule==NULL. The returned structure
185 * will be allocated and initialized but not necessarily populated; it
186 * should not be freed.
188 static struct cached_refs *get_cached_refs(const char *submodule)
190 struct cached_refs *refs = cached_refs;
191 if (!submodule)
192 submodule = "";
193 while (refs) {
194 if (!strcmp(submodule, refs->name))
195 return refs;
196 refs = refs->next;
199 refs = create_cached_refs(submodule);
200 refs->next = cached_refs;
201 cached_refs = refs;
202 return refs;
205 static void invalidate_cached_refs(void)
207 struct cached_refs *refs = cached_refs;
208 while (refs) {
209 clear_cached_refs(refs);
210 refs = refs->next;
214 static void read_packed_refs(FILE *f, struct ref_array *array)
216 struct ref_entry *last = NULL;
217 char refline[PATH_MAX];
218 int flag = REF_ISPACKED;
220 while (fgets(refline, sizeof(refline), f)) {
221 unsigned char sha1[20];
222 const char *name;
223 static const char header[] = "# pack-refs with:";
225 if (!strncmp(refline, header, sizeof(header)-1)) {
226 const char *traits = refline + sizeof(header) - 1;
227 if (strstr(traits, " peeled "))
228 flag |= REF_KNOWS_PEELED;
229 /* perhaps other traits later as well */
230 continue;
233 name = parse_ref_line(refline, sha1);
234 if (name) {
235 add_ref(name, sha1, flag, array, &last);
236 continue;
238 if (last &&
239 refline[0] == '^' &&
240 strlen(refline) == 42 &&
241 refline[41] == '\n' &&
242 !get_sha1_hex(refline + 1, sha1))
243 hashcpy(last->peeled, sha1);
245 sort_ref_array(array);
248 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
250 add_ref(name, sha1, flag, &extra_refs, NULL);
253 void clear_extra_refs(void)
255 free_ref_array(&extra_refs);
258 static struct ref_array *get_packed_refs(const char *submodule)
260 struct cached_refs *refs = get_cached_refs(submodule);
262 if (!refs->did_packed) {
263 const char *packed_refs_file;
264 FILE *f;
266 if (submodule)
267 packed_refs_file = git_path_submodule(submodule, "packed-refs");
268 else
269 packed_refs_file = git_path("packed-refs");
270 f = fopen(packed_refs_file, "r");
271 if (f) {
272 read_packed_refs(f, &refs->packed);
273 fclose(f);
275 refs->did_packed = 1;
277 return &refs->packed;
280 static void get_ref_dir(const char *submodule, const char *base,
281 struct ref_array *array)
283 DIR *dir;
284 const char *path;
286 if (submodule)
287 path = git_path_submodule(submodule, "%s", base);
288 else
289 path = git_path("%s", base);
292 dir = opendir(path);
294 if (dir) {
295 struct dirent *de;
296 int baselen = strlen(base);
297 char *ref = xmalloc(baselen + 257);
299 memcpy(ref, base, baselen);
300 if (baselen && base[baselen-1] != '/')
301 ref[baselen++] = '/';
303 while ((de = readdir(dir)) != NULL) {
304 unsigned char sha1[20];
305 struct stat st;
306 int flag;
307 int namelen;
308 const char *refdir;
310 if (de->d_name[0] == '.')
311 continue;
312 namelen = strlen(de->d_name);
313 if (namelen > 255)
314 continue;
315 if (has_extension(de->d_name, ".lock"))
316 continue;
317 memcpy(ref + baselen, de->d_name, namelen+1);
318 refdir = submodule
319 ? git_path_submodule(submodule, "%s", ref)
320 : git_path("%s", ref);
321 if (stat(refdir, &st) < 0)
322 continue;
323 if (S_ISDIR(st.st_mode)) {
324 get_ref_dir(submodule, ref, array);
325 continue;
327 if (submodule) {
328 hashclr(sha1);
329 flag = 0;
330 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
331 hashclr(sha1);
332 flag |= REF_BROKEN;
334 } else
335 if (!resolve_ref(ref, sha1, 1, &flag)) {
336 hashclr(sha1);
337 flag |= REF_BROKEN;
339 add_ref(ref, sha1, flag, array, NULL);
341 free(ref);
342 closedir(dir);
346 struct warn_if_dangling_data {
347 FILE *fp;
348 const char *refname;
349 const char *msg_fmt;
352 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
353 int flags, void *cb_data)
355 struct warn_if_dangling_data *d = cb_data;
356 const char *resolves_to;
357 unsigned char junk[20];
359 if (!(flags & REF_ISSYMREF))
360 return 0;
362 resolves_to = resolve_ref(refname, junk, 0, NULL);
363 if (!resolves_to || strcmp(resolves_to, d->refname))
364 return 0;
366 fprintf(d->fp, d->msg_fmt, refname);
367 return 0;
370 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
372 struct warn_if_dangling_data data;
374 data.fp = fp;
375 data.refname = refname;
376 data.msg_fmt = msg_fmt;
377 for_each_rawref(warn_if_dangling_symref, &data);
380 static struct ref_array *get_loose_refs(const char *submodule)
382 struct cached_refs *refs = get_cached_refs(submodule);
384 if (!refs->did_loose) {
385 get_ref_dir(submodule, "refs", &refs->loose);
386 sort_ref_array(&refs->loose);
387 refs->did_loose = 1;
389 return &refs->loose;
392 /* We allow "recursive" symbolic refs. Only within reason, though */
393 #define MAXDEPTH 5
394 #define MAXREFLEN (1024)
397 * Called by resolve_gitlink_ref_recursive() after it failed to read
398 * from "name", which is "module/.git/<refname>". Find <refname> in
399 * the packed-refs file for the submodule.
401 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
403 int retval = -1;
404 struct ref_entry *ref;
405 struct ref_array *array;
407 /* being defensive: resolve_gitlink_ref() did this for us */
408 if (pathlen < 6 || memcmp(name + pathlen - 6, "/.git/", 6))
409 die("Oops");
410 name[pathlen - 6] = '\0'; /* make it path to the submodule */
411 array = get_packed_refs(name);
412 ref = search_ref_array(array, refname);
413 if (ref != NULL) {
414 memcpy(result, ref->sha1, 20);
415 retval = 0;
417 return retval;
420 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
422 int fd, len = strlen(refname);
423 char buffer[128], *p;
425 if (recursion > MAXDEPTH || len > MAXREFLEN)
426 return -1;
427 memcpy(name + pathlen, refname, len+1);
428 fd = open(name, O_RDONLY);
429 if (fd < 0)
430 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
432 len = read(fd, buffer, sizeof(buffer)-1);
433 close(fd);
434 if (len < 0)
435 return -1;
436 while (len && isspace(buffer[len-1]))
437 len--;
438 buffer[len] = 0;
440 /* Was it a detached head or an old-fashioned symlink? */
441 if (!get_sha1_hex(buffer, result))
442 return 0;
444 /* Symref? */
445 if (strncmp(buffer, "ref:", 4))
446 return -1;
447 p = buffer + 4;
448 while (isspace(*p))
449 p++;
451 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
454 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
456 int len = strlen(path), retval;
457 char *gitdir;
458 const char *tmp;
460 while (len && path[len-1] == '/')
461 len--;
462 if (!len)
463 return -1;
464 gitdir = xmalloc(len + MAXREFLEN + 8);
465 memcpy(gitdir, path, len);
466 memcpy(gitdir + len, "/.git", 6);
467 len += 5;
469 tmp = read_gitfile(gitdir);
470 if (tmp) {
471 free(gitdir);
472 len = strlen(tmp);
473 gitdir = xmalloc(len + MAXREFLEN + 3);
474 memcpy(gitdir, tmp, len);
476 gitdir[len] = '/';
477 gitdir[++len] = '\0';
478 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
479 free(gitdir);
480 return retval;
484 * Try to read ref from the packed references. On success, set sha1
485 * and return 0; otherwise, return -1.
487 static int get_packed_ref(const char *ref, unsigned char *sha1)
489 struct ref_array *packed = get_packed_refs(NULL);
490 struct ref_entry *entry = search_ref_array(packed, ref);
491 if (entry) {
492 hashcpy(sha1, entry->sha1);
493 return 0;
495 return -1;
498 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
500 int depth = MAXDEPTH;
501 ssize_t len;
502 char buffer[256];
503 static char ref_buffer[256];
504 char path[PATH_MAX];
506 if (flag)
507 *flag = 0;
509 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
510 return NULL;
512 for (;;) {
513 struct stat st;
514 char *buf;
515 int fd;
517 if (--depth < 0)
518 return NULL;
520 git_snpath(path, sizeof(path), "%s", ref);
522 if (lstat(path, &st) < 0) {
523 if (errno != ENOENT)
524 return NULL;
526 * The loose reference file does not exist;
527 * check for a packed reference.
529 if (!get_packed_ref(ref, sha1)) {
530 if (flag)
531 *flag |= REF_ISPACKED;
532 return ref;
534 /* The reference is not a packed reference, either. */
535 if (reading) {
536 return NULL;
537 } else {
538 hashclr(sha1);
539 return ref;
543 /* Follow "normalized" - ie "refs/.." symlinks by hand */
544 if (S_ISLNK(st.st_mode)) {
545 len = readlink(path, buffer, sizeof(buffer)-1);
546 if (len < 0)
547 return NULL;
548 buffer[len] = 0;
549 if (!prefixcmp(buffer, "refs/") &&
550 !check_refname_format(buffer, 0)) {
551 strcpy(ref_buffer, buffer);
552 ref = ref_buffer;
553 if (flag)
554 *flag |= REF_ISSYMREF;
555 continue;
559 /* Is it a directory? */
560 if (S_ISDIR(st.st_mode)) {
561 errno = EISDIR;
562 return NULL;
566 * Anything else, just open it and try to use it as
567 * a ref
569 fd = open(path, O_RDONLY);
570 if (fd < 0)
571 return NULL;
572 len = read_in_full(fd, buffer, sizeof(buffer)-1);
573 close(fd);
574 if (len < 0)
575 return NULL;
576 while (len && isspace(buffer[len-1]))
577 len--;
578 buffer[len] = '\0';
581 * Is it a symbolic ref?
583 if (prefixcmp(buffer, "ref:"))
584 break;
585 buf = buffer + 4;
586 while (isspace(*buf))
587 buf++;
588 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
589 warning("symbolic reference in %s is formatted incorrectly",
590 path);
591 return NULL;
593 ref = strcpy(ref_buffer, buf);
594 if (flag)
595 *flag |= REF_ISSYMREF;
597 /* Please note that FETCH_HEAD has a second line containing other data. */
598 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
599 warning("reference in %s is formatted incorrectly", path);
600 return NULL;
602 return ref;
605 /* The argument to filter_refs */
606 struct ref_filter {
607 const char *pattern;
608 each_ref_fn *fn;
609 void *cb_data;
612 int read_ref(const char *ref, unsigned char *sha1)
614 if (resolve_ref(ref, sha1, 1, NULL))
615 return 0;
616 return -1;
619 #define DO_FOR_EACH_INCLUDE_BROKEN 01
620 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
621 int flags, void *cb_data, struct ref_entry *entry)
623 if (prefixcmp(entry->name, base))
624 return 0;
626 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
627 if (entry->flag & REF_BROKEN)
628 return 0; /* ignore dangling symref */
629 if (!has_sha1_file(entry->sha1)) {
630 error("%s does not point to a valid object!", entry->name);
631 return 0;
634 current_ref = entry;
635 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
638 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
639 void *data)
641 struct ref_filter *filter = (struct ref_filter *)data;
642 if (fnmatch(filter->pattern, ref, 0))
643 return 0;
644 return filter->fn(ref, sha, flags, filter->cb_data);
647 int peel_ref(const char *ref, unsigned char *sha1)
649 int flag;
650 unsigned char base[20];
651 struct object *o;
653 if (current_ref && (current_ref->name == ref
654 || !strcmp(current_ref->name, ref))) {
655 if (current_ref->flag & REF_KNOWS_PEELED) {
656 hashcpy(sha1, current_ref->peeled);
657 return 0;
659 hashcpy(base, current_ref->sha1);
660 goto fallback;
663 if (!resolve_ref(ref, base, 1, &flag))
664 return -1;
666 if ((flag & REF_ISPACKED)) {
667 struct ref_array *array = get_packed_refs(NULL);
668 struct ref_entry *r = search_ref_array(array, ref);
670 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
671 hashcpy(sha1, r->peeled);
672 return 0;
676 fallback:
677 o = parse_object(base);
678 if (o && o->type == OBJ_TAG) {
679 o = deref_tag(o, ref, 0);
680 if (o) {
681 hashcpy(sha1, o->sha1);
682 return 0;
685 return -1;
688 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
689 int trim, int flags, void *cb_data)
691 int retval = 0, i, p = 0, l = 0;
692 struct ref_array *packed = get_packed_refs(submodule);
693 struct ref_array *loose = get_loose_refs(submodule);
695 struct ref_array *extra = &extra_refs;
697 for (i = 0; i < extra->nr; i++)
698 retval = do_one_ref(base, fn, trim, flags, cb_data, extra->refs[i]);
700 while (p < packed->nr && l < loose->nr) {
701 struct ref_entry *entry;
702 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
703 if (!cmp) {
704 p++;
705 continue;
707 if (cmp > 0) {
708 entry = loose->refs[l++];
709 } else {
710 entry = packed->refs[p++];
712 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
713 if (retval)
714 goto end_each;
717 if (l < loose->nr) {
718 p = l;
719 packed = loose;
722 for (; p < packed->nr; p++) {
723 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
724 if (retval)
725 goto end_each;
728 end_each:
729 current_ref = NULL;
730 return retval;
734 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
736 unsigned char sha1[20];
737 int flag;
739 if (submodule) {
740 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
741 return fn("HEAD", sha1, 0, cb_data);
743 return 0;
746 if (resolve_ref("HEAD", sha1, 1, &flag))
747 return fn("HEAD", sha1, flag, cb_data);
749 return 0;
752 int head_ref(each_ref_fn fn, void *cb_data)
754 return do_head_ref(NULL, fn, cb_data);
757 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
759 return do_head_ref(submodule, fn, cb_data);
762 int for_each_ref(each_ref_fn fn, void *cb_data)
764 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
767 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
769 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
772 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
774 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
777 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
778 each_ref_fn fn, void *cb_data)
780 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
783 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
785 return for_each_ref_in("refs/tags/", fn, cb_data);
788 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
790 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
793 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
795 return for_each_ref_in("refs/heads/", fn, cb_data);
798 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
800 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
803 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
805 return for_each_ref_in("refs/remotes/", fn, cb_data);
808 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
810 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
813 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
815 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
818 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
820 struct strbuf buf = STRBUF_INIT;
821 int ret = 0;
822 unsigned char sha1[20];
823 int flag;
825 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
826 if (resolve_ref(buf.buf, sha1, 1, &flag))
827 ret = fn(buf.buf, sha1, flag, cb_data);
828 strbuf_release(&buf);
830 return ret;
833 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
835 struct strbuf buf = STRBUF_INIT;
836 int ret;
837 strbuf_addf(&buf, "%srefs/", get_git_namespace());
838 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
839 strbuf_release(&buf);
840 return ret;
843 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
844 const char *prefix, void *cb_data)
846 struct strbuf real_pattern = STRBUF_INIT;
847 struct ref_filter filter;
848 int ret;
850 if (!prefix && prefixcmp(pattern, "refs/"))
851 strbuf_addstr(&real_pattern, "refs/");
852 else if (prefix)
853 strbuf_addstr(&real_pattern, prefix);
854 strbuf_addstr(&real_pattern, pattern);
856 if (!has_glob_specials(pattern)) {
857 /* Append implied '/' '*' if not present. */
858 if (real_pattern.buf[real_pattern.len - 1] != '/')
859 strbuf_addch(&real_pattern, '/');
860 /* No need to check for '*', there is none. */
861 strbuf_addch(&real_pattern, '*');
864 filter.pattern = real_pattern.buf;
865 filter.fn = fn;
866 filter.cb_data = cb_data;
867 ret = for_each_ref(filter_refs, &filter);
869 strbuf_release(&real_pattern);
870 return ret;
873 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
875 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
878 int for_each_rawref(each_ref_fn fn, void *cb_data)
880 return do_for_each_ref(NULL, "", fn, 0,
881 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
885 * Make sure "ref" is something reasonable to have under ".git/refs/";
886 * We do not like it if:
888 * - any path component of it begins with ".", or
889 * - it has double dots "..", or
890 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
891 * - it ends with a "/".
892 * - it ends with ".lock"
893 * - it contains a "\" (backslash)
896 /* Return true iff ch is not allowed in reference names. */
897 static inline int bad_ref_char(int ch)
899 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
900 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
901 return 1;
902 /* 2.13 Pattern Matching Notation */
903 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
904 return 1;
905 return 0;
909 * Try to read one refname component from the front of ref. Return
910 * the length of the component found, or -1 if the component is not
911 * legal.
913 static int check_refname_component(const char *ref, int flags)
915 const char *cp;
916 char last = '\0';
918 for (cp = ref; ; cp++) {
919 char ch = *cp;
920 if (ch == '\0' || ch == '/')
921 break;
922 if (bad_ref_char(ch))
923 return -1; /* Illegal character in refname. */
924 if (last == '.' && ch == '.')
925 return -1; /* Refname contains "..". */
926 if (last == '@' && ch == '{')
927 return -1; /* Refname contains "@{". */
928 last = ch;
930 if (cp == ref)
931 return -1; /* Component has zero length. */
932 if (ref[0] == '.') {
933 if (!(flags & REFNAME_DOT_COMPONENT))
934 return -1; /* Component starts with '.'. */
936 * Even if leading dots are allowed, don't allow "."
937 * as a component (".." is prevented by a rule above).
939 if (ref[1] == '\0')
940 return -1; /* Component equals ".". */
942 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
943 return -1; /* Refname ends with ".lock". */
944 return cp - ref;
947 int check_refname_format(const char *ref, int flags)
949 int component_len, component_count = 0;
951 while (1) {
952 /* We are at the start of a path component. */
953 component_len = check_refname_component(ref, flags);
954 if (component_len < 0) {
955 if ((flags & REFNAME_REFSPEC_PATTERN) &&
956 ref[0] == '*' &&
957 (ref[1] == '\0' || ref[1] == '/')) {
958 /* Accept one wildcard as a full refname component. */
959 flags &= ~REFNAME_REFSPEC_PATTERN;
960 component_len = 1;
961 } else {
962 return -1;
965 component_count++;
966 if (ref[component_len] == '\0')
967 break;
968 /* Skip to next component. */
969 ref += component_len + 1;
972 if (ref[component_len - 1] == '.')
973 return -1; /* Refname ends with '.'. */
974 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
975 return -1; /* Refname has only one component. */
976 return 0;
979 const char *prettify_refname(const char *name)
981 return name + (
982 !prefixcmp(name, "refs/heads/") ? 11 :
983 !prefixcmp(name, "refs/tags/") ? 10 :
984 !prefixcmp(name, "refs/remotes/") ? 13 :
988 const char *ref_rev_parse_rules[] = {
989 "%.*s",
990 "refs/%.*s",
991 "refs/tags/%.*s",
992 "refs/heads/%.*s",
993 "refs/remotes/%.*s",
994 "refs/remotes/%.*s/HEAD",
995 NULL
998 const char *ref_fetch_rules[] = {
999 "%.*s",
1000 "refs/%.*s",
1001 "refs/heads/%.*s",
1002 NULL
1005 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1007 const char **p;
1008 const int abbrev_name_len = strlen(abbrev_name);
1010 for (p = rules; *p; p++) {
1011 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1012 return 1;
1016 return 0;
1019 static struct ref_lock *verify_lock(struct ref_lock *lock,
1020 const unsigned char *old_sha1, int mustexist)
1022 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1023 error("Can't verify ref %s", lock->ref_name);
1024 unlock_ref(lock);
1025 return NULL;
1027 if (hashcmp(lock->old_sha1, old_sha1)) {
1028 error("Ref %s is at %s but expected %s", lock->ref_name,
1029 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1030 unlock_ref(lock);
1031 return NULL;
1033 return lock;
1036 static int remove_empty_directories(const char *file)
1038 /* we want to create a file but there is a directory there;
1039 * if that is an empty directory (or a directory that contains
1040 * only empty directories), remove them.
1042 struct strbuf path;
1043 int result;
1045 strbuf_init(&path, 20);
1046 strbuf_addstr(&path, file);
1048 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1050 strbuf_release(&path);
1052 return result;
1055 static int is_refname_available(const char *ref, const char *oldref,
1056 struct ref_array *array, int quiet)
1058 int i, namlen = strlen(ref); /* e.g. 'foo/bar' */
1059 for (i = 0; i < array->nr; i++ ) {
1060 struct ref_entry *entry = array->refs[i];
1061 /* entry->name could be 'foo' or 'foo/bar/baz' */
1062 if (!oldref || strcmp(oldref, entry->name)) {
1063 int len = strlen(entry->name);
1064 int cmplen = (namlen < len) ? namlen : len;
1065 const char *lead = (namlen < len) ? entry->name : ref;
1066 if (!strncmp(ref, entry->name, cmplen) &&
1067 lead[cmplen] == '/') {
1068 if (!quiet)
1069 error("'%s' exists; cannot create '%s'",
1070 entry->name, ref);
1071 return 0;
1075 return 1;
1078 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1080 char *ref_file;
1081 const char *orig_ref = ref;
1082 struct ref_lock *lock;
1083 int last_errno = 0;
1084 int type, lflags;
1085 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1086 int missing = 0;
1088 lock = xcalloc(1, sizeof(struct ref_lock));
1089 lock->lock_fd = -1;
1091 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1092 if (!ref && errno == EISDIR) {
1093 /* we are trying to lock foo but we used to
1094 * have foo/bar which now does not exist;
1095 * it is normal for the empty directory 'foo'
1096 * to remain.
1098 ref_file = git_path("%s", orig_ref);
1099 if (remove_empty_directories(ref_file)) {
1100 last_errno = errno;
1101 error("there are still refs under '%s'", orig_ref);
1102 goto error_return;
1104 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1106 if (type_p)
1107 *type_p = type;
1108 if (!ref) {
1109 last_errno = errno;
1110 error("unable to resolve reference %s: %s",
1111 orig_ref, strerror(errno));
1112 goto error_return;
1114 missing = is_null_sha1(lock->old_sha1);
1115 /* When the ref did not exist and we are creating it,
1116 * make sure there is no existing ref that is packed
1117 * whose name begins with our refname, nor a ref whose
1118 * name is a proper prefix of our refname.
1120 if (missing &&
1121 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1122 last_errno = ENOTDIR;
1123 goto error_return;
1126 lock->lk = xcalloc(1, sizeof(struct lock_file));
1128 lflags = LOCK_DIE_ON_ERROR;
1129 if (flags & REF_NODEREF) {
1130 ref = orig_ref;
1131 lflags |= LOCK_NODEREF;
1133 lock->ref_name = xstrdup(ref);
1134 lock->orig_ref_name = xstrdup(orig_ref);
1135 ref_file = git_path("%s", ref);
1136 if (missing)
1137 lock->force_write = 1;
1138 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1139 lock->force_write = 1;
1141 if (safe_create_leading_directories(ref_file)) {
1142 last_errno = errno;
1143 error("unable to create directory for %s", ref_file);
1144 goto error_return;
1147 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1148 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1150 error_return:
1151 unlock_ref(lock);
1152 errno = last_errno;
1153 return NULL;
1156 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1158 char refpath[PATH_MAX];
1159 if (check_refname_format(ref, 0))
1160 return NULL;
1161 strcpy(refpath, mkpath("refs/%s", ref));
1162 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1165 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1167 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1168 return NULL;
1169 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1172 static struct lock_file packlock;
1174 static int repack_without_ref(const char *refname)
1176 struct ref_array *packed;
1177 struct ref_entry *ref;
1178 int fd, i;
1180 packed = get_packed_refs(NULL);
1181 ref = search_ref_array(packed, refname);
1182 if (ref == NULL)
1183 return 0;
1184 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1185 if (fd < 0) {
1186 unable_to_lock_error(git_path("packed-refs"), errno);
1187 return error("cannot delete '%s' from packed refs", refname);
1190 for (i = 0; i < packed->nr; i++) {
1191 char line[PATH_MAX + 100];
1192 int len;
1194 ref = packed->refs[i];
1196 if (!strcmp(refname, ref->name))
1197 continue;
1198 len = snprintf(line, sizeof(line), "%s %s\n",
1199 sha1_to_hex(ref->sha1), ref->name);
1200 /* this should not happen but just being defensive */
1201 if (len > sizeof(line))
1202 die("too long a refname '%s'", ref->name);
1203 write_or_die(fd, line, len);
1205 return commit_lock_file(&packlock);
1208 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1210 struct ref_lock *lock;
1211 int err, i = 0, ret = 0, flag = 0;
1213 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1214 if (!lock)
1215 return 1;
1216 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1217 /* loose */
1218 const char *path;
1220 if (!(delopt & REF_NODEREF)) {
1221 i = strlen(lock->lk->filename) - 5; /* .lock */
1222 lock->lk->filename[i] = 0;
1223 path = lock->lk->filename;
1224 } else {
1225 path = git_path("%s", refname);
1227 err = unlink_or_warn(path);
1228 if (err && errno != ENOENT)
1229 ret = 1;
1231 if (!(delopt & REF_NODEREF))
1232 lock->lk->filename[i] = '.';
1234 /* removing the loose one could have resurrected an earlier
1235 * packed one. Also, if it was not loose we need to repack
1236 * without it.
1238 ret |= repack_without_ref(refname);
1240 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1241 invalidate_cached_refs();
1242 unlock_ref(lock);
1243 return ret;
1247 * People using contrib's git-new-workdir have .git/logs/refs ->
1248 * /some/other/path/.git/logs/refs, and that may live on another device.
1250 * IOW, to avoid cross device rename errors, the temporary renamed log must
1251 * live into logs/refs.
1253 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1255 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1257 static const char renamed_ref[] = "RENAMED-REF";
1258 unsigned char sha1[20], orig_sha1[20];
1259 int flag = 0, logmoved = 0;
1260 struct ref_lock *lock;
1261 struct stat loginfo;
1262 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1263 const char *symref = NULL;
1265 if (log && S_ISLNK(loginfo.st_mode))
1266 return error("reflog for %s is a symlink", oldref);
1268 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1269 if (flag & REF_ISSYMREF)
1270 return error("refname %s is a symbolic ref, renaming it is not supported",
1271 oldref);
1272 if (!symref)
1273 return error("refname %s not found", oldref);
1275 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1276 return 1;
1278 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1279 return 1;
1281 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1282 if (!lock)
1283 return error("unable to lock %s", renamed_ref);
1284 lock->force_write = 1;
1285 if (write_ref_sha1(lock, orig_sha1, logmsg))
1286 return error("unable to save current sha1 in %s", renamed_ref);
1288 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1289 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1290 oldref, strerror(errno));
1292 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1293 error("unable to delete old %s", oldref);
1294 goto rollback;
1297 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1298 if (errno==EISDIR) {
1299 if (remove_empty_directories(git_path("%s", newref))) {
1300 error("Directory not empty: %s", newref);
1301 goto rollback;
1303 } else {
1304 error("unable to delete existing %s", newref);
1305 goto rollback;
1309 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1310 error("unable to create directory for %s", newref);
1311 goto rollback;
1314 retry:
1315 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1316 if (errno==EISDIR || errno==ENOTDIR) {
1318 * rename(a, b) when b is an existing
1319 * directory ought to result in ISDIR, but
1320 * Solaris 5.8 gives ENOTDIR. Sheesh.
1322 if (remove_empty_directories(git_path("logs/%s", newref))) {
1323 error("Directory not empty: logs/%s", newref);
1324 goto rollback;
1326 goto retry;
1327 } else {
1328 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1329 newref, strerror(errno));
1330 goto rollback;
1333 logmoved = log;
1335 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1336 if (!lock) {
1337 error("unable to lock %s for update", newref);
1338 goto rollback;
1340 lock->force_write = 1;
1341 hashcpy(lock->old_sha1, orig_sha1);
1342 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1343 error("unable to write current sha1 into %s", newref);
1344 goto rollback;
1347 return 0;
1349 rollback:
1350 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1351 if (!lock) {
1352 error("unable to lock %s for rollback", oldref);
1353 goto rollbacklog;
1356 lock->force_write = 1;
1357 flag = log_all_ref_updates;
1358 log_all_ref_updates = 0;
1359 if (write_ref_sha1(lock, orig_sha1, NULL))
1360 error("unable to write current sha1 into %s", oldref);
1361 log_all_ref_updates = flag;
1363 rollbacklog:
1364 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1365 error("unable to restore logfile %s from %s: %s",
1366 oldref, newref, strerror(errno));
1367 if (!logmoved && log &&
1368 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1369 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1370 oldref, strerror(errno));
1372 return 1;
1375 int close_ref(struct ref_lock *lock)
1377 if (close_lock_file(lock->lk))
1378 return -1;
1379 lock->lock_fd = -1;
1380 return 0;
1383 int commit_ref(struct ref_lock *lock)
1385 if (commit_lock_file(lock->lk))
1386 return -1;
1387 lock->lock_fd = -1;
1388 return 0;
1391 void unlock_ref(struct ref_lock *lock)
1393 /* Do not free lock->lk -- atexit() still looks at them */
1394 if (lock->lk)
1395 rollback_lock_file(lock->lk);
1396 free(lock->ref_name);
1397 free(lock->orig_ref_name);
1398 free(lock);
1402 * copy the reflog message msg to buf, which has been allocated sufficiently
1403 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1404 * because reflog file is one line per entry.
1406 static int copy_msg(char *buf, const char *msg)
1408 char *cp = buf;
1409 char c;
1410 int wasspace = 1;
1412 *cp++ = '\t';
1413 while ((c = *msg++)) {
1414 if (wasspace && isspace(c))
1415 continue;
1416 wasspace = isspace(c);
1417 if (wasspace)
1418 c = ' ';
1419 *cp++ = c;
1421 while (buf < cp && isspace(cp[-1]))
1422 cp--;
1423 *cp++ = '\n';
1424 return cp - buf;
1427 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1429 int logfd, oflags = O_APPEND | O_WRONLY;
1431 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1432 if (log_all_ref_updates &&
1433 (!prefixcmp(ref_name, "refs/heads/") ||
1434 !prefixcmp(ref_name, "refs/remotes/") ||
1435 !prefixcmp(ref_name, "refs/notes/") ||
1436 !strcmp(ref_name, "HEAD"))) {
1437 if (safe_create_leading_directories(logfile) < 0)
1438 return error("unable to create directory for %s",
1439 logfile);
1440 oflags |= O_CREAT;
1443 logfd = open(logfile, oflags, 0666);
1444 if (logfd < 0) {
1445 if (!(oflags & O_CREAT) && errno == ENOENT)
1446 return 0;
1448 if ((oflags & O_CREAT) && errno == EISDIR) {
1449 if (remove_empty_directories(logfile)) {
1450 return error("There are still logs under '%s'",
1451 logfile);
1453 logfd = open(logfile, oflags, 0666);
1456 if (logfd < 0)
1457 return error("Unable to append to %s: %s",
1458 logfile, strerror(errno));
1461 adjust_shared_perm(logfile);
1462 close(logfd);
1463 return 0;
1466 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1467 const unsigned char *new_sha1, const char *msg)
1469 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1470 unsigned maxlen, len;
1471 int msglen;
1472 char log_file[PATH_MAX];
1473 char *logrec;
1474 const char *committer;
1476 if (log_all_ref_updates < 0)
1477 log_all_ref_updates = !is_bare_repository();
1479 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1480 if (result)
1481 return result;
1483 logfd = open(log_file, oflags);
1484 if (logfd < 0)
1485 return 0;
1486 msglen = msg ? strlen(msg) : 0;
1487 committer = git_committer_info(0);
1488 maxlen = strlen(committer) + msglen + 100;
1489 logrec = xmalloc(maxlen);
1490 len = sprintf(logrec, "%s %s %s\n",
1491 sha1_to_hex(old_sha1),
1492 sha1_to_hex(new_sha1),
1493 committer);
1494 if (msglen)
1495 len += copy_msg(logrec + len - 1, msg) - 1;
1496 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1497 free(logrec);
1498 if (close(logfd) != 0 || written != len)
1499 return error("Unable to append to %s", log_file);
1500 return 0;
1503 static int is_branch(const char *refname)
1505 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1508 int write_ref_sha1(struct ref_lock *lock,
1509 const unsigned char *sha1, const char *logmsg)
1511 static char term = '\n';
1512 struct object *o;
1514 if (!lock)
1515 return -1;
1516 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1517 unlock_ref(lock);
1518 return 0;
1520 o = parse_object(sha1);
1521 if (!o) {
1522 error("Trying to write ref %s with nonexistent object %s",
1523 lock->ref_name, sha1_to_hex(sha1));
1524 unlock_ref(lock);
1525 return -1;
1527 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1528 error("Trying to write non-commit object %s to branch %s",
1529 sha1_to_hex(sha1), lock->ref_name);
1530 unlock_ref(lock);
1531 return -1;
1533 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1534 write_in_full(lock->lock_fd, &term, 1) != 1
1535 || close_ref(lock) < 0) {
1536 error("Couldn't write %s", lock->lk->filename);
1537 unlock_ref(lock);
1538 return -1;
1540 invalidate_cached_refs();
1541 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1542 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1543 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1544 unlock_ref(lock);
1545 return -1;
1547 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1549 * Special hack: If a branch is updated directly and HEAD
1550 * points to it (may happen on the remote side of a push
1551 * for example) then logically the HEAD reflog should be
1552 * updated too.
1553 * A generic solution implies reverse symref information,
1554 * but finding all symrefs pointing to the given branch
1555 * would be rather costly for this rare event (the direct
1556 * update of a branch) to be worth it. So let's cheat and
1557 * check with HEAD only which should cover 99% of all usage
1558 * scenarios (even 100% of the default ones).
1560 unsigned char head_sha1[20];
1561 int head_flag;
1562 const char *head_ref;
1563 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1564 if (head_ref && (head_flag & REF_ISSYMREF) &&
1565 !strcmp(head_ref, lock->ref_name))
1566 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1568 if (commit_ref(lock)) {
1569 error("Couldn't set %s", lock->ref_name);
1570 unlock_ref(lock);
1571 return -1;
1573 unlock_ref(lock);
1574 return 0;
1577 int create_symref(const char *ref_target, const char *refs_heads_master,
1578 const char *logmsg)
1580 const char *lockpath;
1581 char ref[1000];
1582 int fd, len, written;
1583 char *git_HEAD = git_pathdup("%s", ref_target);
1584 unsigned char old_sha1[20], new_sha1[20];
1586 if (logmsg && read_ref(ref_target, old_sha1))
1587 hashclr(old_sha1);
1589 if (safe_create_leading_directories(git_HEAD) < 0)
1590 return error("unable to create directory for %s", git_HEAD);
1592 #ifndef NO_SYMLINK_HEAD
1593 if (prefer_symlink_refs) {
1594 unlink(git_HEAD);
1595 if (!symlink(refs_heads_master, git_HEAD))
1596 goto done;
1597 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1599 #endif
1601 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1602 if (sizeof(ref) <= len) {
1603 error("refname too long: %s", refs_heads_master);
1604 goto error_free_return;
1606 lockpath = mkpath("%s.lock", git_HEAD);
1607 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1608 if (fd < 0) {
1609 error("Unable to open %s for writing", lockpath);
1610 goto error_free_return;
1612 written = write_in_full(fd, ref, len);
1613 if (close(fd) != 0 || written != len) {
1614 error("Unable to write to %s", lockpath);
1615 goto error_unlink_return;
1617 if (rename(lockpath, git_HEAD) < 0) {
1618 error("Unable to create %s", git_HEAD);
1619 goto error_unlink_return;
1621 if (adjust_shared_perm(git_HEAD)) {
1622 error("Unable to fix permissions on %s", lockpath);
1623 error_unlink_return:
1624 unlink_or_warn(lockpath);
1625 error_free_return:
1626 free(git_HEAD);
1627 return -1;
1630 #ifndef NO_SYMLINK_HEAD
1631 done:
1632 #endif
1633 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1634 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1636 free(git_HEAD);
1637 return 0;
1640 static char *ref_msg(const char *line, const char *endp)
1642 const char *ep;
1643 line += 82;
1644 ep = memchr(line, '\n', endp - line);
1645 if (!ep)
1646 ep = endp;
1647 return xmemdupz(line, ep - line);
1650 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)
1652 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1653 char *tz_c;
1654 int logfd, tz, reccnt = 0;
1655 struct stat st;
1656 unsigned long date;
1657 unsigned char logged_sha1[20];
1658 void *log_mapped;
1659 size_t mapsz;
1661 logfile = git_path("logs/%s", ref);
1662 logfd = open(logfile, O_RDONLY, 0);
1663 if (logfd < 0)
1664 die_errno("Unable to read log '%s'", logfile);
1665 fstat(logfd, &st);
1666 if (!st.st_size)
1667 die("Log %s is empty.", logfile);
1668 mapsz = xsize_t(st.st_size);
1669 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1670 logdata = log_mapped;
1671 close(logfd);
1673 lastrec = NULL;
1674 rec = logend = logdata + st.st_size;
1675 while (logdata < rec) {
1676 reccnt++;
1677 if (logdata < rec && *(rec-1) == '\n')
1678 rec--;
1679 lastgt = NULL;
1680 while (logdata < rec && *(rec-1) != '\n') {
1681 rec--;
1682 if (*rec == '>')
1683 lastgt = rec;
1685 if (!lastgt)
1686 die("Log %s is corrupt.", logfile);
1687 date = strtoul(lastgt + 1, &tz_c, 10);
1688 if (date <= at_time || cnt == 0) {
1689 tz = strtoul(tz_c, NULL, 10);
1690 if (msg)
1691 *msg = ref_msg(rec, logend);
1692 if (cutoff_time)
1693 *cutoff_time = date;
1694 if (cutoff_tz)
1695 *cutoff_tz = tz;
1696 if (cutoff_cnt)
1697 *cutoff_cnt = reccnt - 1;
1698 if (lastrec) {
1699 if (get_sha1_hex(lastrec, logged_sha1))
1700 die("Log %s is corrupt.", logfile);
1701 if (get_sha1_hex(rec + 41, sha1))
1702 die("Log %s is corrupt.", logfile);
1703 if (hashcmp(logged_sha1, sha1)) {
1704 warning("Log %s has gap after %s.",
1705 logfile, show_date(date, tz, DATE_RFC2822));
1708 else if (date == at_time) {
1709 if (get_sha1_hex(rec + 41, sha1))
1710 die("Log %s is corrupt.", logfile);
1712 else {
1713 if (get_sha1_hex(rec + 41, logged_sha1))
1714 die("Log %s is corrupt.", logfile);
1715 if (hashcmp(logged_sha1, sha1)) {
1716 warning("Log %s unexpectedly ended on %s.",
1717 logfile, show_date(date, tz, DATE_RFC2822));
1720 munmap(log_mapped, mapsz);
1721 return 0;
1723 lastrec = rec;
1724 if (cnt > 0)
1725 cnt--;
1728 rec = logdata;
1729 while (rec < logend && *rec != '>' && *rec != '\n')
1730 rec++;
1731 if (rec == logend || *rec == '\n')
1732 die("Log %s is corrupt.", logfile);
1733 date = strtoul(rec + 1, &tz_c, 10);
1734 tz = strtoul(tz_c, NULL, 10);
1735 if (get_sha1_hex(logdata, sha1))
1736 die("Log %s is corrupt.", logfile);
1737 if (is_null_sha1(sha1)) {
1738 if (get_sha1_hex(logdata + 41, sha1))
1739 die("Log %s is corrupt.", logfile);
1741 if (msg)
1742 *msg = ref_msg(logdata, logend);
1743 munmap(log_mapped, mapsz);
1745 if (cutoff_time)
1746 *cutoff_time = date;
1747 if (cutoff_tz)
1748 *cutoff_tz = tz;
1749 if (cutoff_cnt)
1750 *cutoff_cnt = reccnt;
1751 return 1;
1754 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1756 const char *logfile;
1757 FILE *logfp;
1758 struct strbuf sb = STRBUF_INIT;
1759 int ret = 0;
1761 logfile = git_path("logs/%s", ref);
1762 logfp = fopen(logfile, "r");
1763 if (!logfp)
1764 return -1;
1766 if (ofs) {
1767 struct stat statbuf;
1768 if (fstat(fileno(logfp), &statbuf) ||
1769 statbuf.st_size < ofs ||
1770 fseek(logfp, -ofs, SEEK_END) ||
1771 strbuf_getwholeline(&sb, logfp, '\n')) {
1772 fclose(logfp);
1773 strbuf_release(&sb);
1774 return -1;
1778 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1779 unsigned char osha1[20], nsha1[20];
1780 char *email_end, *message;
1781 unsigned long timestamp;
1782 int tz;
1784 /* old SP new SP name <email> SP time TAB msg LF */
1785 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1786 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1787 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1788 !(email_end = strchr(sb.buf + 82, '>')) ||
1789 email_end[1] != ' ' ||
1790 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1791 !message || message[0] != ' ' ||
1792 (message[1] != '+' && message[1] != '-') ||
1793 !isdigit(message[2]) || !isdigit(message[3]) ||
1794 !isdigit(message[4]) || !isdigit(message[5]))
1795 continue; /* corrupt? */
1796 email_end[1] = '\0';
1797 tz = strtol(message + 1, NULL, 10);
1798 if (message[6] != '\t')
1799 message += 6;
1800 else
1801 message += 7;
1802 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1803 cb_data);
1804 if (ret)
1805 break;
1807 fclose(logfp);
1808 strbuf_release(&sb);
1809 return ret;
1812 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1814 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1817 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1819 DIR *dir = opendir(git_path("logs/%s", base));
1820 int retval = 0;
1822 if (dir) {
1823 struct dirent *de;
1824 int baselen = strlen(base);
1825 char *log = xmalloc(baselen + 257);
1827 memcpy(log, base, baselen);
1828 if (baselen && base[baselen-1] != '/')
1829 log[baselen++] = '/';
1831 while ((de = readdir(dir)) != NULL) {
1832 struct stat st;
1833 int namelen;
1835 if (de->d_name[0] == '.')
1836 continue;
1837 namelen = strlen(de->d_name);
1838 if (namelen > 255)
1839 continue;
1840 if (has_extension(de->d_name, ".lock"))
1841 continue;
1842 memcpy(log + baselen, de->d_name, namelen+1);
1843 if (stat(git_path("logs/%s", log), &st) < 0)
1844 continue;
1845 if (S_ISDIR(st.st_mode)) {
1846 retval = do_for_each_reflog(log, fn, cb_data);
1847 } else {
1848 unsigned char sha1[20];
1849 if (!resolve_ref(log, sha1, 0, NULL))
1850 retval = error("bad ref for %s", log);
1851 else
1852 retval = fn(log, sha1, 0, cb_data);
1854 if (retval)
1855 break;
1857 free(log);
1858 closedir(dir);
1860 else if (*base)
1861 return errno;
1862 return retval;
1865 int for_each_reflog(each_ref_fn fn, void *cb_data)
1867 return do_for_each_reflog("", fn, cb_data);
1870 int update_ref(const char *action, const char *refname,
1871 const unsigned char *sha1, const unsigned char *oldval,
1872 int flags, enum action_on_err onerr)
1874 static struct ref_lock *lock;
1875 lock = lock_any_ref_for_update(refname, oldval, flags);
1876 if (!lock) {
1877 const char *str = "Cannot lock the ref '%s'.";
1878 switch (onerr) {
1879 case MSG_ON_ERR: error(str, refname); break;
1880 case DIE_ON_ERR: die(str, refname); break;
1881 case QUIET_ON_ERR: break;
1883 return 1;
1885 if (write_ref_sha1(lock, sha1, action) < 0) {
1886 const char *str = "Cannot update the ref '%s'.";
1887 switch (onerr) {
1888 case MSG_ON_ERR: error(str, refname); break;
1889 case DIE_ON_ERR: die(str, refname); break;
1890 case QUIET_ON_ERR: break;
1892 return 1;
1894 return 0;
1897 int ref_exists(const char *refname)
1899 unsigned char sha1[20];
1900 return !!resolve_ref(refname, sha1, 1, NULL);
1903 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1905 for ( ; list; list = list->next)
1906 if (!strcmp(list->name, name))
1907 return (struct ref *)list;
1908 return NULL;
1912 * generate a format suitable for scanf from a ref_rev_parse_rules
1913 * rule, that is replace the "%.*s" spec with a "%s" spec
1915 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1917 char *spec;
1919 spec = strstr(rule, "%.*s");
1920 if (!spec || strstr(spec + 4, "%.*s"))
1921 die("invalid rule in ref_rev_parse_rules: %s", rule);
1923 /* copy all until spec */
1924 strncpy(scanf_fmt, rule, spec - rule);
1925 scanf_fmt[spec - rule] = '\0';
1926 /* copy new spec */
1927 strcat(scanf_fmt, "%s");
1928 /* copy remaining rule */
1929 strcat(scanf_fmt, spec + 4);
1931 return;
1934 char *shorten_unambiguous_ref(const char *ref, int strict)
1936 int i;
1937 static char **scanf_fmts;
1938 static int nr_rules;
1939 char *short_name;
1941 /* pre generate scanf formats from ref_rev_parse_rules[] */
1942 if (!nr_rules) {
1943 size_t total_len = 0;
1945 /* the rule list is NULL terminated, count them first */
1946 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1947 /* no +1 because strlen("%s") < strlen("%.*s") */
1948 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1950 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1952 total_len = 0;
1953 for (i = 0; i < nr_rules; i++) {
1954 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1955 + total_len;
1956 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1957 total_len += strlen(ref_rev_parse_rules[i]);
1961 /* bail out if there are no rules */
1962 if (!nr_rules)
1963 return xstrdup(ref);
1965 /* buffer for scanf result, at most ref must fit */
1966 short_name = xstrdup(ref);
1968 /* skip first rule, it will always match */
1969 for (i = nr_rules - 1; i > 0 ; --i) {
1970 int j;
1971 int rules_to_fail = i;
1972 int short_name_len;
1974 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1975 continue;
1977 short_name_len = strlen(short_name);
1980 * in strict mode, all (except the matched one) rules
1981 * must fail to resolve to a valid non-ambiguous ref
1983 if (strict)
1984 rules_to_fail = nr_rules;
1987 * check if the short name resolves to a valid ref,
1988 * but use only rules prior to the matched one
1990 for (j = 0; j < rules_to_fail; j++) {
1991 const char *rule = ref_rev_parse_rules[j];
1992 unsigned char short_objectname[20];
1993 char refname[PATH_MAX];
1995 /* skip matched rule */
1996 if (i == j)
1997 continue;
2000 * the short name is ambiguous, if it resolves
2001 * (with this previous rule) to a valid ref
2002 * read_ref() returns 0 on success
2004 mksnpath(refname, sizeof(refname),
2005 rule, short_name_len, short_name);
2006 if (!read_ref(refname, short_objectname))
2007 break;
2011 * short name is non-ambiguous if all previous rules
2012 * haven't resolved to a valid ref
2014 if (j == rules_to_fail)
2015 return short_name;
2018 free(short_name);
2019 return xstrdup(ref);