1#include "cache.h"
2#include "refs.h"
3#include "object.h"
4#include "tag.h"
5/* ISSYMREF=01 and ISPACKED=02 are public interfaces */
7#define REF_KNOWS_PEELED 04
8struct ref_list {
10 struct ref_list *next;
11 unsigned char flag; /* ISSYMREF? ISPACKED? */
12 unsigned char sha1[20];
13 unsigned char peeled[20];
14 char name[FLEX_ARRAY];
15};
16static const char *parse_ref_line(char *line, unsigned char *sha1)
18{
19 /*
20 * 42: the answer to everything.
21 *
22 * In this case, it happens to be the answer to
23 * 40 (length of sha1 hex representation)
24 * +1 (space in between hex and name)
25 * +1 (newline at the end of the line)
26 */
27 int len = strlen(line) - 42;
28 if (len <= 0)
30 return NULL;
31 if (get_sha1_hex(line, sha1) < 0)
32 return NULL;
33 if (!isspace(line[40]))
34 return NULL;
35 line += 41;
36 if (isspace(*line))
37 return NULL;
38 if (line[len] != '\n')
39 return NULL;
40 line[len] = 0;
41 return line;
43}
44static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
46 int flag, struct ref_list *list,
47 struct ref_list **new_entry)
48{
49 int len;
50 struct ref_list **p = &list, *entry;
51 /* Find the place to insert the ref into.. */
53 while ((entry = *p) != NULL) {
54 int cmp = strcmp(entry->name, name);
55 if (cmp > 0)
56 break;
57 /* Same as existing entry? */
59 if (!cmp) {
60 if (new_entry)
61 *new_entry = entry;
62 return list;
63 }
64 p = &entry->next;
65 }
66 /* Allocate it and add it in.. */
68 len = strlen(name) + 1;
69 entry = xmalloc(sizeof(struct ref_list) + len);
70 hashcpy(entry->sha1, sha1);
71 hashclr(entry->peeled);
72 memcpy(entry->name, name, len);
73 entry->flag = flag;
74 entry->next = *p;
75 *p = entry;
76 if (new_entry)
77 *new_entry = entry;
78 return list;
79}
80/*
82 * Future: need to be in "struct repository"
83 * when doing a full libification.
84 */
85struct cached_refs {
86 char did_loose;
87 char did_packed;
88 struct ref_list *loose;
89 struct ref_list *packed;
90} cached_refs;
91static void free_ref_list(struct ref_list *list)
93{
94 struct ref_list *next;
95 for ( ; list; list = next) {
96 next = list->next;
97 free(list);
98 }
99}
100static void invalidate_cached_refs(void)
102{
103 struct cached_refs *ca = &cached_refs;
104 if (ca->did_loose && ca->loose)
106 free_ref_list(ca->loose);
107 if (ca->did_packed && ca->packed)
108 free_ref_list(ca->packed);
109 ca->loose = ca->packed = NULL;
110 ca->did_loose = ca->did_packed = 0;
111}
112static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
114{
115 struct ref_list *list = NULL;
116 struct ref_list *last = NULL;
117 char refline[PATH_MAX];
118 int flag = REF_ISPACKED;
119 while (fgets(refline, sizeof(refline), f)) {
121 unsigned char sha1[20];
122 const char *name;
123 static const char header[] = "# pack-refs with:";
124 if (!strncmp(refline, header, sizeof(header)-1)) {
126 const char *traits = refline + sizeof(header) - 1;
127 if (strstr(traits, " peeled "))
128 flag |= REF_KNOWS_PEELED;
129 /* perhaps other traits later as well */
130 continue;
131 }
132 name = parse_ref_line(refline, sha1);
134 if (name) {
135 list = add_ref(name, sha1, flag, list, &last);
136 continue;
137 }
138 if (last &&
139 refline[0] == '^' &&
140 strlen(refline) == 42 &&
141 refline[41] == '\n' &&
142 !get_sha1_hex(refline + 1, sha1))
143 hashcpy(last->peeled, sha1);
144 }
145 cached_refs->packed = list;
146}
147static struct ref_list *get_packed_refs(void)
149{
150 if (!cached_refs.did_packed) {
151 FILE *f = fopen(git_path("packed-refs"), "r");
152 cached_refs.packed = NULL;
153 if (f) {
154 read_packed_refs(f, &cached_refs);
155 fclose(f);
156 }
157 cached_refs.did_packed = 1;
158 }
159 return cached_refs.packed;
160}
161static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
163{
164 DIR *dir = opendir(git_path("%s", base));
165 if (dir) {
167 struct dirent *de;
168 int baselen = strlen(base);
169 char *ref = xmalloc(baselen + 257);
170 memcpy(ref, base, baselen);
172 if (baselen && base[baselen-1] != '/')
173 ref[baselen++] = '/';
174 while ((de = readdir(dir)) != NULL) {
176 unsigned char sha1[20];
177 struct stat st;
178 int flag;
179 int namelen;
180 if (de->d_name[0] == '.')
182 continue;
183 namelen = strlen(de->d_name);
184 if (namelen > 255)
185 continue;
186 if (has_extension(de->d_name, ".lock"))
187 continue;
188 memcpy(ref + baselen, de->d_name, namelen+1);
189 if (stat(git_path("%s", ref), &st) < 0)
190 continue;
191 if (S_ISDIR(st.st_mode)) {
192 list = get_ref_dir(ref, list);
193 continue;
194 }
195 if (!resolve_ref(ref, sha1, 1, &flag)) {
196 error("%s points nowhere!", ref);
197 continue;
198 }
199 list = add_ref(ref, sha1, flag, list, NULL);
200 }
201 free(ref);
202 closedir(dir);
203 }
204 return list;
205}
206static struct ref_list *get_loose_refs(void)
208{
209 if (!cached_refs.did_loose) {
210 cached_refs.loose = get_ref_dir("refs", NULL);
211 cached_refs.did_loose = 1;
212 }
213 return cached_refs.loose;
214}
215/* We allow "recursive" symbolic refs. Only within reason, though */
217#define MAXDEPTH 5
218const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
220{
221 int depth = MAXDEPTH, len;
222 char buffer[256];
223 static char ref_buffer[256];
224 if (flag)
226 *flag = 0;
227 for (;;) {
229 const char *path = git_path("%s", ref);
230 struct stat st;
231 char *buf;
232 int fd;
233 if (--depth < 0)
235 return NULL;
236 /* Special case: non-existing file.
238 * Not having the refs/heads/new-branch is OK
239 * if we are writing into it, so is .git/HEAD
240 * that points at refs/heads/master still to be
241 * born. It is NOT OK if we are resolving for
242 * reading.
243 */
244 if (lstat(path, &st) < 0) {
245 struct ref_list *list = get_packed_refs();
246 while (list) {
247 if (!strcmp(ref, list->name)) {
248 hashcpy(sha1, list->sha1);
249 if (flag)
250 *flag |= REF_ISPACKED;
251 return ref;
252 }
253 list = list->next;
254 }
255 if (reading || errno != ENOENT)
256 return NULL;
257 hashclr(sha1);
258 return ref;
259 }
260 /* Follow "normalized" - ie "refs/.." symlinks by hand */
262 if (S_ISLNK(st.st_mode)) {
263 len = readlink(path, buffer, sizeof(buffer)-1);
264 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
265 buffer[len] = 0;
266 strcpy(ref_buffer, buffer);
267 ref = ref_buffer;
268 if (flag)
269 *flag |= REF_ISSYMREF;
270 continue;
271 }
272 }
273 /* Is it a directory? */
275 if (S_ISDIR(st.st_mode)) {
276 errno = EISDIR;
277 return NULL;
278 }
279 /*
281 * Anything else, just open it and try to use it as
282 * a ref
283 */
284 fd = open(path, O_RDONLY);
285 if (fd < 0)
286 return NULL;
287 len = read_in_full(fd, buffer, sizeof(buffer)-1);
288 close(fd);
289 /*
291 * Is it a symbolic ref?
292 */
293 if (len < 4 || memcmp("ref:", buffer, 4))
294 break;
295 buf = buffer + 4;
296 len -= 4;
297 while (len && isspace(*buf))
298 buf++, len--;
299 while (len && isspace(buf[len-1]))
300 len--;
301 buf[len] = 0;
302 memcpy(ref_buffer, buf, len + 1);
303 ref = ref_buffer;
304 if (flag)
305 *flag |= REF_ISSYMREF;
306 }
307 if (len < 40 || get_sha1_hex(buffer, sha1))
308 return NULL;
309 return ref;
310}
311int read_ref(const char *ref, unsigned char *sha1)
313{
314 if (resolve_ref(ref, sha1, 1, NULL))
315 return 0;
316 return -1;
317}
318static int do_one_ref(const char *base, each_ref_fn fn, int trim,
320 void *cb_data, struct ref_list *entry)
321{
322 if (strncmp(base, entry->name, trim))
323 return 0;
324 if (is_null_sha1(entry->sha1))
325 return 0;
326 if (!has_sha1_file(entry->sha1)) {
327 error("%s does not point to a valid object!", entry->name);
328 return 0;
329 }
330 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
331}
332int peel_ref(const char *ref, unsigned char *sha1)
334{
335 int flag;
336 unsigned char base[20];
337 struct object *o;
338 if (!resolve_ref(ref, base, 1, &flag))
340 return -1;
341 if ((flag & REF_ISPACKED)) {
343 struct ref_list *list = get_packed_refs();
344 while (list) {
346 if (!strcmp(list->name, ref)) {
347 if (list->flag & REF_KNOWS_PEELED) {
348 hashcpy(sha1, list->peeled);
349 return 0;
350 }
351 /* older pack-refs did not leave peeled ones */
352 break;
353 }
354 list = list->next;
355 }
356 }
357 /* fallback - callers should not call this for unpacked refs */
359 o = parse_object(base);
360 if (o->type == OBJ_TAG) {
361 o = deref_tag(o, ref, 0);
362 if (o) {
363 hashcpy(sha1, o->sha1);
364 return 0;
365 }
366 }
367 return -1;
368}
369static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
371 void *cb_data)
372{
373 int retval;
374 struct ref_list *packed = get_packed_refs();
375 struct ref_list *loose = get_loose_refs();
376 while (packed && loose) {
378 struct ref_list *entry;
379 int cmp = strcmp(packed->name, loose->name);
380 if (!cmp) {
381 packed = packed->next;
382 continue;
383 }
384 if (cmp > 0) {
385 entry = loose;
386 loose = loose->next;
387 } else {
388 entry = packed;
389 packed = packed->next;
390 }
391 retval = do_one_ref(base, fn, trim, cb_data, entry);
392 if (retval)
393 return retval;
394 }
395 for (packed = packed ? packed : loose; packed; packed = packed->next) {
397 retval = do_one_ref(base, fn, trim, cb_data, packed);
398 if (retval)
399 return retval;
400 }
401 return 0;
402}
403int head_ref(each_ref_fn fn, void *cb_data)
405{
406 unsigned char sha1[20];
407 int flag;
408 if (resolve_ref("HEAD", sha1, 1, &flag))
410 return fn("HEAD", sha1, flag, cb_data);
411 return 0;
412}
413int for_each_ref(each_ref_fn fn, void *cb_data)
415{
416 return do_for_each_ref("refs/", fn, 0, cb_data);
417}
418int for_each_tag_ref(each_ref_fn fn, void *cb_data)
420{
421 return do_for_each_ref("refs/tags/", fn, 10, cb_data);
422}
423int for_each_branch_ref(each_ref_fn fn, void *cb_data)
425{
426 return do_for_each_ref("refs/heads/", fn, 11, cb_data);
427}
428int for_each_remote_ref(each_ref_fn fn, void *cb_data)
430{
431 return do_for_each_ref("refs/remotes/", fn, 13, cb_data);
432}
433/* NEEDSWORK: This is only used by ssh-upload and it should go; the
435 * caller should do resolve_ref or read_ref like everybody else. Or
436 * maybe everybody else should use get_ref_sha1() instead of doing
437 * read_ref().
438 */
439int get_ref_sha1(const char *ref, unsigned char *sha1)
440{
441 if (check_ref_format(ref))
442 return -1;
443 return read_ref(mkpath("refs/%s", ref), sha1);
444}
445/*
447 * Make sure "ref" is something reasonable to have under ".git/refs/";
448 * We do not like it if:
449 *
450 * - any path component of it begins with ".", or
451 * - it has double dots "..", or
452 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
453 * - it ends with a "/".
454 */
455static inline int bad_ref_char(int ch)
457{
458 return (((unsigned) ch) <= ' ' ||
459 ch == '~' || ch == '^' || ch == ':' ||
460 /* 2.13 Pattern Matching Notation */
461 ch == '?' || ch == '*' || ch == '[');
462}
463int check_ref_format(const char *ref)
465{
466 int ch, level;
467 const char *cp = ref;
468 level = 0;
470 while (1) {
471 while ((ch = *cp++) == '/')
472 ; /* tolerate duplicated slashes */
473 if (!ch)
474 return -1; /* should not end with slashes */
475 /* we are at the beginning of the path component */
477 if (ch == '.' || bad_ref_char(ch))
478 return -1;
479 /* scan the rest of the path component */
481 while ((ch = *cp++) != 0) {
482 if (bad_ref_char(ch))
483 return -1;
484 if (ch == '/')
485 break;
486 if (ch == '.' && *cp == '.')
487 return -1;
488 }
489 level++;
490 if (!ch) {
491 if (level < 2)
492 return -2; /* at least of form "heads/blah" */
493 return 0;
494 }
495 }
496}
497static struct ref_lock *verify_lock(struct ref_lock *lock,
499 const unsigned char *old_sha1, int mustexist)
500{
501 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
502 error("Can't verify ref %s", lock->ref_name);
503 unlock_ref(lock);
504 return NULL;
505 }
506 if (hashcmp(lock->old_sha1, old_sha1)) {
507 error("Ref %s is at %s but expected %s", lock->ref_name,
508 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
509 unlock_ref(lock);
510 return NULL;
511 }
512 return lock;
513}
514static int remove_empty_dir_recursive(char *path, int len)
516{
517 DIR *dir = opendir(path);
518 struct dirent *e;
519 int ret = 0;
520 if (!dir)
522 return -1;
523 if (path[len-1] != '/')
524 path[len++] = '/';
525 while ((e = readdir(dir)) != NULL) {
526 struct stat st;
527 int namlen;
528 if ((e->d_name[0] == '.') &&
529 ((e->d_name[1] == 0) ||
530 ((e->d_name[1] == '.') && e->d_name[2] == 0)))
531 continue; /* "." and ".." */
532 namlen = strlen(e->d_name);
534 if ((len + namlen < PATH_MAX) &&
535 strcpy(path + len, e->d_name) &&
536 !lstat(path, &st) &&
537 S_ISDIR(st.st_mode) &&
538 !remove_empty_dir_recursive(path, len + namlen))
539 continue; /* happy */
540 /* path too long, stat fails, or non-directory still exists */
542 ret = -1;
543 break;
544 }
545 closedir(dir);
546 if (!ret) {
547 path[len] = 0;
548 ret = rmdir(path);
549 }
550 return ret;
551}
552static int remove_empty_directories(char *file)
554{
555 /* we want to create a file but there is a directory there;
556 * if that is an empty directory (or a directory that contains
557 * only empty directories), remove them.
558 */
559 char path[PATH_MAX];
560 int len = strlen(file);
561 if (len >= PATH_MAX) /* path too long ;-) */
563 return -1;
564 strcpy(path, file);
565 return remove_empty_dir_recursive(path, len);
566}
567static int is_refname_available(const char *ref, const char *oldref,
569 struct ref_list *list, int quiet)
570{
571 int namlen = strlen(ref); /* e.g. 'foo/bar' */
572 while (list) {
573 /* list->name could be 'foo' or 'foo/bar/baz' */
574 if (!oldref || strcmp(oldref, list->name)) {
575 int len = strlen(list->name);
576 int cmplen = (namlen < len) ? namlen : len;
577 const char *lead = (namlen < len) ? list->name : ref;
578 if (!strncmp(ref, list->name, cmplen) &&
579 lead[cmplen] == '/') {
580 if (!quiet)
581 error("'%s' exists; cannot create '%s'",
582 list->name, ref);
583 return 0;
584 }
585 }
586 list = list->next;
587 }
588 return 1;
589}
590static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int *flag)
592{
593 char *ref_file;
594 const char *orig_ref = ref;
595 struct ref_lock *lock;
596 struct stat st;
597 int last_errno = 0;
598 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
599 lock = xcalloc(1, sizeof(struct ref_lock));
601 lock->lock_fd = -1;
602 ref = resolve_ref(ref, lock->old_sha1, mustexist, flag);
604 if (!ref && errno == EISDIR) {
605 /* we are trying to lock foo but we used to
606 * have foo/bar which now does not exist;
607 * it is normal for the empty directory 'foo'
608 * to remain.
609 */
610 ref_file = git_path("%s", orig_ref);
611 if (remove_empty_directories(ref_file)) {
612 last_errno = errno;
613 error("there are still refs under '%s'", orig_ref);
614 goto error_return;
615 }
616 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, flag);
617 }
618 if (!ref) {
619 last_errno = errno;
620 error("unable to resolve reference %s: %s",
621 orig_ref, strerror(errno));
622 goto error_return;
623 }
624 /* When the ref did not exist and we are creating it,
625 * make sure there is no existing ref that is packed
626 * whose name begins with our refname, nor a ref whose
627 * name is a proper prefix of our refname.
628 */
629 if (is_null_sha1(lock->old_sha1) &&
630 !is_refname_available(ref, NULL, get_packed_refs(), 0))
631 goto error_return;
632 lock->lk = xcalloc(1, sizeof(struct lock_file));
634 lock->ref_name = xstrdup(ref);
636 lock->orig_ref_name = xstrdup(orig_ref);
637 ref_file = git_path("%s", ref);
638 lock->force_write = lstat(ref_file, &st) && errno == ENOENT;
639 if (safe_create_leading_directories(ref_file)) {
641 last_errno = errno;
642 error("unable to create directory for %s", ref_file);
643 goto error_return;
644 }
645 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, 1);
646 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
648 error_return:
650 unlock_ref(lock);
651 errno = last_errno;
652 return NULL;
653}
654struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
656{
657 char refpath[PATH_MAX];
658 if (check_ref_format(ref))
659 return NULL;
660 strcpy(refpath, mkpath("refs/%s", ref));
661 return lock_ref_sha1_basic(refpath, old_sha1, NULL);
662}
663struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1)
665{
666 if (check_ref_format(ref) == -1)
667 return NULL;
668 return lock_ref_sha1_basic(ref, old_sha1, NULL);
669}
670static struct lock_file packlock;
672static int repack_without_ref(const char *refname)
674{
675 struct ref_list *list, *packed_ref_list;
676 int fd;
677 int found = 0;
678 packed_ref_list = get_packed_refs();
680 for (list = packed_ref_list; list; list = list->next) {
681 if (!strcmp(refname, list->name)) {
682 found = 1;
683 break;
684 }
685 }
686 if (!found)
687 return 0;
688 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
689 if (fd < 0)
690 return error("cannot delete '%s' from packed refs", refname);
691 for (list = packed_ref_list; list; list = list->next) {
693 char line[PATH_MAX + 100];
694 int len;
695 if (!strcmp(refname, list->name))
697 continue;
698 len = snprintf(line, sizeof(line), "%s %s\n",
699 sha1_to_hex(list->sha1), list->name);
700 /* this should not happen but just being defensive */
701 if (len > sizeof(line))
702 die("too long a refname '%s'", list->name);
703 write_or_die(fd, line, len);
704 }
705 return commit_lock_file(&packlock);
706}
707int delete_ref(const char *refname, unsigned char *sha1)
709{
710 struct ref_lock *lock;
711 int err, i, ret = 0, flag = 0;
712 lock = lock_ref_sha1_basic(refname, sha1, &flag);
714 if (!lock)
715 return 1;
716 if (!(flag & REF_ISPACKED)) {
717 /* loose */
718 i = strlen(lock->lk->filename) - 5; /* .lock */
719 lock->lk->filename[i] = 0;
720 err = unlink(lock->lk->filename);
721 if (err) {
722 ret = 1;
723 error("unlink(%s) failed: %s",
724 lock->lk->filename, strerror(errno));
725 }
726 lock->lk->filename[i] = '.';
727 }
728 /* removing the loose one could have resurrected an earlier
729 * packed one. Also, if it was not loose we need to repack
730 * without it.
731 */
732 ret |= repack_without_ref(refname);
733 err = unlink(git_path("logs/%s", lock->ref_name));
735 if (err && errno != ENOENT)
736 fprintf(stderr, "warning: unlink(%s) failed: %s",
737 git_path("logs/%s", lock->ref_name), strerror(errno));
738 invalidate_cached_refs();
739 unlock_ref(lock);
740 return ret;
741}
742int rename_ref(const char *oldref, const char *newref, const char *logmsg)
744{
745 static const char renamed_ref[] = "RENAMED-REF";
746 unsigned char sha1[20], orig_sha1[20];
747 int flag = 0, logmoved = 0;
748 struct ref_lock *lock;
749 struct stat loginfo;
750 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
751 if (S_ISLNK(loginfo.st_mode))
753 return error("reflog for %s is a symlink", oldref);
754 if (!resolve_ref(oldref, orig_sha1, 1, &flag))
756 return error("refname %s not found", oldref);
757 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
759 return 1;
760 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
762 return 1;
763 lock = lock_ref_sha1_basic(renamed_ref, NULL, NULL);
765 if (!lock)
766 return error("unable to lock %s", renamed_ref);
767 lock->force_write = 1;
768 if (write_ref_sha1(lock, orig_sha1, logmsg))
769 return error("unable to save current sha1 in %s", renamed_ref);
770 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
772 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
773 oldref, strerror(errno));
774 if (delete_ref(oldref, orig_sha1)) {
776 error("unable to delete old %s", oldref);
777 goto rollback;
778 }
779 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) {
781 if (errno==EISDIR) {
782 if (remove_empty_directories(git_path("%s", newref))) {
783 error("Directory not empty: %s", newref);
784 goto rollback;
785 }
786 } else {
787 error("unable to delete existing %s", newref);
788 goto rollback;
789 }
790 }
791 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
793 error("unable to create directory for %s", newref);
794 goto rollback;
795 }
796 retry:
798 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
799 if (errno==EISDIR || errno==ENOTDIR) {
800 /*
801 * rename(a, b) when b is an existing
802 * directory ought to result in ISDIR, but
803 * Solaris 5.8 gives ENOTDIR. Sheesh.
804 */
805 if (remove_empty_directories(git_path("logs/%s", newref))) {
806 error("Directory not empty: logs/%s", newref);
807 goto rollback;
808 }
809 goto retry;
810 } else {
811 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
812 newref, strerror(errno));
813 goto rollback;
814 }
815 }
816 logmoved = log;
817 lock = lock_ref_sha1_basic(newref, NULL, NULL);
819 if (!lock) {
820 error("unable to lock %s for update", newref);
821 goto rollback;
822 }
823 lock->force_write = 1;
825 hashcpy(lock->old_sha1, orig_sha1);
826 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
827 error("unable to write current sha1 into %s", newref);
828 goto rollback;
829 }
830 if (!strncmp(oldref, "refs/heads/", 11) &&
832 !strncmp(newref, "refs/heads/", 11)) {
833 char oldsection[1024], newsection[1024];
834 snprintf(oldsection, 1024, "branch.%s", oldref + 11);
836 snprintf(newsection, 1024, "branch.%s", newref + 11);
837 if (git_config_rename_section(oldsection, newsection) < 0)
838 return 1;
839 }
840 return 0;
842 rollback:
844 lock = lock_ref_sha1_basic(oldref, NULL, NULL);
845 if (!lock) {
846 error("unable to lock %s for rollback", oldref);
847 goto rollbacklog;
848 }
849 lock->force_write = 1;
851 flag = log_all_ref_updates;
852 log_all_ref_updates = 0;
853 if (write_ref_sha1(lock, orig_sha1, NULL))
854 error("unable to write current sha1 into %s", oldref);
855 log_all_ref_updates = flag;
856 rollbacklog:
858 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
859 error("unable to restore logfile %s from %s: %s",
860 oldref, newref, strerror(errno));
861 if (!logmoved && log &&
862 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
863 error("unable to restore logfile %s from tmp-renamed-log: %s",
864 oldref, strerror(errno));
865 return 1;
867}
868void unlock_ref(struct ref_lock *lock)
870{
871 if (lock->lock_fd >= 0) {
872 close(lock->lock_fd);
873 /* Do not free lock->lk -- atexit() still looks at them */
874 if (lock->lk)
875 rollback_lock_file(lock->lk);
876 }
877 free(lock->ref_name);
878 free(lock->orig_ref_name);
879 free(lock);
880}
881static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
883 const unsigned char *new_sha1, const char *msg)
884{
885 int logfd, written, oflags = O_APPEND | O_WRONLY;
886 unsigned maxlen, len;
887 int msglen;
888 char *log_file, *logrec;
889 const char *committer;
890 if (log_all_ref_updates < 0)
892 log_all_ref_updates = !is_bare_repository();
893 log_file = git_path("logs/%s", ref_name);
895 if (log_all_ref_updates &&
897 (!strncmp(ref_name, "refs/heads/", 11) ||
898 !strncmp(ref_name, "refs/remotes/", 13) ||
899 !strcmp(ref_name, "HEAD"))) {
900 if (safe_create_leading_directories(log_file) < 0)
901 return error("unable to create directory for %s",
902 log_file);
903 oflags |= O_CREAT;
904 }
905 logfd = open(log_file, oflags, 0666);
907 if (logfd < 0) {
908 if (!(oflags & O_CREAT) && errno == ENOENT)
909 return 0;
910 if ((oflags & O_CREAT) && errno == EISDIR) {
912 if (remove_empty_directories(log_file)) {
913 return error("There are still logs under '%s'",
914 log_file);
915 }
916 logfd = open(log_file, oflags, 0666);
917 }
918 if (logfd < 0)
920 return error("Unable to append to %s: %s",
921 log_file, strerror(errno));
922 }
923 msglen = 0;
925 if (msg) {
926 /* clean up the message and make sure it is a single line */
927 for ( ; *msg; msg++)
928 if (!isspace(*msg))
929 break;
930 if (*msg) {
931 const char *ep = strchr(msg, '\n');
932 if (ep)
933 msglen = ep - msg;
934 else
935 msglen = strlen(msg);
936 }
937 }
938 committer = git_committer_info(-1);
940 maxlen = strlen(committer) + msglen + 100;
941 logrec = xmalloc(maxlen);
942 len = sprintf(logrec, "%s %s %s\n",
943 sha1_to_hex(old_sha1),
944 sha1_to_hex(new_sha1),
945 committer);
946 if (msglen)
947 len += sprintf(logrec + len - 1, "\t%.*s\n", msglen, msg) - 1;
948 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
949 free(logrec);
950 close(logfd);
951 if (written != len)
952 return error("Unable to append to %s", log_file);
953 return 0;
954}
955int write_ref_sha1(struct ref_lock *lock,
957 const unsigned char *sha1, const char *logmsg)
958{
959 static char term = '\n';
960 if (!lock)
962 return -1;
963 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
964 unlock_ref(lock);
965 return 0;
966 }
967 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
968 write_in_full(lock->lock_fd, &term, 1) != 1
969 || close(lock->lock_fd) < 0) {
970 error("Couldn't write %s", lock->lk->filename);
971 unlock_ref(lock);
972 return -1;
973 }
974 invalidate_cached_refs();
975 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
976 (strcmp(lock->ref_name, lock->orig_ref_name) &&
977 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
978 unlock_ref(lock);
979 return -1;
980 }
981 if (commit_lock_file(lock->lk)) {
982 error("Couldn't set %s", lock->ref_name);
983 unlock_ref(lock);
984 return -1;
985 }
986 lock->lock_fd = -1;
987 unlock_ref(lock);
988 return 0;
989}
990int create_symref(const char *ref_target, const char *refs_heads_master,
992 const char *logmsg)
993{
994 const char *lockpath;
995 char ref[1000];
996 int fd, len, written;
997 char *git_HEAD = xstrdup(git_path("%s", ref_target));
998 unsigned char old_sha1[20], new_sha1[20];
999 if (logmsg && read_ref(ref_target, old_sha1))
1001 hashclr(old_sha1);
1002 if (safe_create_leading_directories(git_HEAD) < 0)
1004 return error("unable to create directory for %s", git_HEAD);
1005#ifndef NO_SYMLINK_HEAD
1007 if (prefer_symlink_refs) {
1008 unlink(git_HEAD);
1009 if (!symlink(refs_heads_master, git_HEAD))
1010 goto done;
1011 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1012 }
1013#endif
1014 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1016 if (sizeof(ref) <= len) {
1017 error("refname too long: %s", refs_heads_master);
1018 goto error_free_return;
1019 }
1020 lockpath = mkpath("%s.lock", git_HEAD);
1021 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1022 if (fd < 0) {
1023 error("Unable to open %s for writing", lockpath);
1024 goto error_free_return;
1025 }
1026 written = write_in_full(fd, ref, len);
1027 close(fd);
1028 if (written != len) {
1029 error("Unable to write to %s", lockpath);
1030 goto error_unlink_return;
1031 }
1032 if (rename(lockpath, git_HEAD) < 0) {
1033 error("Unable to create %s", git_HEAD);
1034 goto error_unlink_return;
1035 }
1036 if (adjust_shared_perm(git_HEAD)) {
1037 error("Unable to fix permissions on %s", lockpath);
1038 error_unlink_return:
1039 unlink(lockpath);
1040 error_free_return:
1041 free(git_HEAD);
1042 return -1;
1043 }
1044 done:
1046 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1047 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1048 free(git_HEAD);
1050 return 0;
1051}
1052static char *ref_msg(const char *line, const char *endp)
1054{
1055 const char *ep;
1056 char *msg;
1057 line += 82;
1059 for (ep = line; ep < endp && *ep != '\n'; ep++)
1060 ;
1061 msg = xmalloc(ep - line + 1);
1062 memcpy(msg, line, ep - line);
1063 msg[ep - line] = 0;
1064 return msg;
1065}
1066int 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)
1068{
1069 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1070 char *tz_c;
1071 int logfd, tz, reccnt = 0;
1072 struct stat st;
1073 unsigned long date;
1074 unsigned char logged_sha1[20];
1075 void *log_mapped;
1076 logfile = git_path("logs/%s", ref);
1078 logfd = open(logfile, O_RDONLY, 0);
1079 if (logfd < 0)
1080 die("Unable to read log %s: %s", logfile, strerror(errno));
1081 fstat(logfd, &st);
1082 if (!st.st_size)
1083 die("Log %s is empty.", logfile);
1084 log_mapped = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0);
1085 logdata = log_mapped;
1086 close(logfd);
1087 lastrec = NULL;
1089 rec = logend = logdata + st.st_size;
1090 while (logdata < rec) {
1091 reccnt++;
1092 if (logdata < rec && *(rec-1) == '\n')
1093 rec--;
1094 lastgt = NULL;
1095 while (logdata < rec && *(rec-1) != '\n') {
1096 rec--;
1097 if (*rec == '>')
1098 lastgt = rec;
1099 }
1100 if (!lastgt)
1101 die("Log %s is corrupt.", logfile);
1102 date = strtoul(lastgt + 1, &tz_c, 10);
1103 if (date <= at_time || cnt == 0) {
1104 tz = strtoul(tz_c, NULL, 10);
1105 if (msg)
1106 *msg = ref_msg(rec, logend);
1107 if (cutoff_time)
1108 *cutoff_time = date;
1109 if (cutoff_tz)
1110 *cutoff_tz = tz;
1111 if (cutoff_cnt)
1112 *cutoff_cnt = reccnt - 1;
1113 if (lastrec) {
1114 if (get_sha1_hex(lastrec, logged_sha1))
1115 die("Log %s is corrupt.", logfile);
1116 if (get_sha1_hex(rec + 41, sha1))
1117 die("Log %s is corrupt.", logfile);
1118 if (hashcmp(logged_sha1, sha1)) {
1119 fprintf(stderr,
1120 "warning: Log %s has gap after %s.\n",
1121 logfile, show_rfc2822_date(date, tz));
1122 }
1123 }
1124 else if (date == at_time) {
1125 if (get_sha1_hex(rec + 41, sha1))
1126 die("Log %s is corrupt.", logfile);
1127 }
1128 else {
1129 if (get_sha1_hex(rec + 41, logged_sha1))
1130 die("Log %s is corrupt.", logfile);
1131 if (hashcmp(logged_sha1, sha1)) {
1132 fprintf(stderr,
1133 "warning: Log %s unexpectedly ended on %s.\n",
1134 logfile, show_rfc2822_date(date, tz));
1135 }
1136 }
1137 munmap(log_mapped, st.st_size);
1138 return 0;
1139 }
1140 lastrec = rec;
1141 if (cnt > 0)
1142 cnt--;
1143 }
1144 rec = logdata;
1146 while (rec < logend && *rec != '>' && *rec != '\n')
1147 rec++;
1148 if (rec == logend || *rec == '\n')
1149 die("Log %s is corrupt.", logfile);
1150 date = strtoul(rec + 1, &tz_c, 10);
1151 tz = strtoul(tz_c, NULL, 10);
1152 if (get_sha1_hex(logdata, sha1))
1153 die("Log %s is corrupt.", logfile);
1154 if (msg)
1155 *msg = ref_msg(logdata, logend);
1156 munmap(log_mapped, st.st_size);
1157 if (cutoff_time)
1159 *cutoff_time = date;
1160 if (cutoff_tz)
1161 *cutoff_tz = tz;
1162 if (cutoff_cnt)
1163 *cutoff_cnt = reccnt;
1164 return 1;
1165}
1166int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1168{
1169 const char *logfile;
1170 FILE *logfp;
1171 char buf[1024];
1172 int ret = 0;
1173 logfile = git_path("logs/%s", ref);
1175 logfp = fopen(logfile, "r");
1176 if (!logfp)
1177 return -1;
1178 while (fgets(buf, sizeof(buf), logfp)) {
1179 unsigned char osha1[20], nsha1[20];
1180 char *email_end, *message;
1181 unsigned long timestamp;
1182 int len, tz;
1183 /* old SP new SP name <email> SP time TAB msg LF */
1185 len = strlen(buf);
1186 if (len < 83 || buf[len-1] != '\n' ||
1187 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1188 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1189 !(email_end = strchr(buf + 82, '>')) ||
1190 email_end[1] != ' ' ||
1191 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1192 !message || message[0] != ' ' ||
1193 (message[1] != '+' && message[1] != '-') ||
1194 !isdigit(message[2]) || !isdigit(message[3]) ||
1195 !isdigit(message[4]) || !isdigit(message[5]))
1196 continue; /* corrupt? */
1197 email_end[1] = '\0';
1198 tz = strtol(message + 1, NULL, 10);
1199 if (message[6] != '\t')
1200 message += 6;
1201 else
1202 message += 7;
1203 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1204 if (ret)
1205 break;
1206 }
1207 fclose(logfp);
1208 return ret;
1209}
1210static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1212{
1213 DIR *dir = opendir(git_path("logs/%s", base));
1214 int retval = 0;
1215 if (dir) {
1217 struct dirent *de;
1218 int baselen = strlen(base);
1219 char *log = xmalloc(baselen + 257);
1220 memcpy(log, base, baselen);
1222 if (baselen && base[baselen-1] != '/')
1223 log[baselen++] = '/';
1224 while ((de = readdir(dir)) != NULL) {
1226 struct stat st;
1227 int namelen;
1228 if (de->d_name[0] == '.')
1230 continue;
1231 namelen = strlen(de->d_name);
1232 if (namelen > 255)
1233 continue;
1234 if (has_extension(de->d_name, ".lock"))
1235 continue;
1236 memcpy(log + baselen, de->d_name, namelen+1);
1237 if (stat(git_path("logs/%s", log), &st) < 0)
1238 continue;
1239 if (S_ISDIR(st.st_mode)) {
1240 retval = do_for_each_reflog(log, fn, cb_data);
1241 } else {
1242 unsigned char sha1[20];
1243 if (!resolve_ref(log, sha1, 0, NULL))
1244 retval = error("bad ref for %s", log);
1245 else
1246 retval = fn(log, sha1, 0, cb_data);
1247 }
1248 if (retval)
1249 break;
1250 }
1251 free(log);
1252 closedir(dir);
1253 }
1254 else if (*base)
1255 return errno;
1256 return retval;
1257}
1258int for_each_reflog(each_ref_fn fn, void *cb_data)
1260{
1261 return do_for_each_reflog("", fn, cb_data);
1262}