Merge branch 'maint'
[git/git.git] / refs.c
CommitLineData
95fc7512 1#include "cache.h"
85023577 2#include "refs.h"
cf0adba7
JH
3#include "object.h"
4#include "tag.h"
7155b727 5#include "dir.h"
95fc7512 6
f4204ab9
JH
7/* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8#define REF_KNOWS_PEELED 04
e01de1c9 9#define REF_BROKEN 010
f4204ab9 10
e1e22e37
LT
11struct ref_list {
12 struct ref_list *next;
f4204ab9 13 unsigned char flag; /* ISSYMREF? ISPACKED? */
e1e22e37 14 unsigned char sha1[20];
f4204ab9 15 unsigned char peeled[20];
e1e22e37
LT
16 char name[FLEX_ARRAY];
17};
18
f4204ab9 19static const char *parse_ref_line(char *line, unsigned char *sha1)
e1e22e37
LT
20{
21 /*
22 * 42: the answer to everything.
23 *
24 * In this case, it happens to be the answer to
25 * 40 (length of sha1 hex representation)
26 * +1 (space in between hex and name)
27 * +1 (newline at the end of the line)
28 */
29 int len = strlen(line) - 42;
30
31 if (len <= 0)
32 return NULL;
33 if (get_sha1_hex(line, sha1) < 0)
34 return NULL;
35 if (!isspace(line[40]))
36 return NULL;
37 line += 41;
f4204ab9
JH
38 if (isspace(*line))
39 return NULL;
e1e22e37
LT
40 if (line[len] != '\n')
41 return NULL;
42 line[len] = 0;
cf0adba7 43
e1e22e37
LT
44 return line;
45}
46
8da19775 47static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
f4204ab9
JH
48 int flag, struct ref_list *list,
49 struct ref_list **new_entry)
e1e22e37
LT
50{
51 int len;
c774aab9 52 struct ref_list *entry;
e1e22e37
LT
53
54 /* Allocate it and add it in.. */
55 len = strlen(name) + 1;
56 entry = xmalloc(sizeof(struct ref_list) + len);
57 hashcpy(entry->sha1, sha1);
f4204ab9 58 hashclr(entry->peeled);
e1e22e37 59 memcpy(entry->name, name, len);
8da19775 60 entry->flag = flag;
c774aab9 61 entry->next = list;
f4204ab9
JH
62 if (new_entry)
63 *new_entry = entry;
c774aab9
JP
64 return entry;
65}
66
67/* merge sort the ref list */
68static struct ref_list *sort_ref_list(struct ref_list *list)
69{
70 int psize, qsize, last_merge_count, cmp;
71 struct ref_list *p, *q, *l, *e;
72 struct ref_list *new_list = list;
73 int k = 1;
74 int merge_count = 0;
75
76 if (!list)
77 return list;
78
79 do {
80 last_merge_count = merge_count;
81 merge_count = 0;
82
83 psize = 0;
84
85 p = new_list;
86 q = new_list;
87 new_list = NULL;
88 l = NULL;
89
90 while (p) {
91 merge_count++;
92
93 while (psize < k && q->next) {
94 q = q->next;
95 psize++;
96 }
97 qsize = k;
98
99 while ((psize > 0) || (qsize > 0 && q)) {
100 if (qsize == 0 || !q) {
101 e = p;
102 p = p->next;
103 psize--;
104 } else if (psize == 0) {
105 e = q;
106 q = q->next;
107 qsize--;
108 } else {
109 cmp = strcmp(q->name, p->name);
110 if (cmp < 0) {
111 e = q;
112 q = q->next;
113 qsize--;
114 } else if (cmp > 0) {
115 e = p;
116 p = p->next;
117 psize--;
118 } else {
119 if (hashcmp(q->sha1, p->sha1))
120 die("Duplicated ref, and SHA1s don't match: %s",
121 q->name);
122 warning("Duplicated ref: %s", q->name);
123 e = q;
124 q = q->next;
125 qsize--;
126 free(e);
127 e = p;
128 p = p->next;
129 psize--;
130 }
131 }
132
133 e->next = NULL;
134
135 if (l)
136 l->next = e;
137 if (!new_list)
138 new_list = e;
139 l = e;
140 }
141
142 p = q;
143 };
144
145 k = k * 2;
146 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
147
148 return new_list;
e1e22e37
LT
149}
150
5e290ff7
JH
151/*
152 * Future: need to be in "struct repository"
153 * when doing a full libification.
154 */
4175e9e3 155static struct cached_refs {
5e290ff7
JH
156 char did_loose;
157 char did_packed;
158 struct ref_list *loose;
159 struct ref_list *packed;
160} cached_refs;
0ae91be0 161static struct ref_list *current_ref;
5e290ff7 162
e142a3c6
DB
163static struct ref_list *extra_refs;
164
5e290ff7
JH
165static void free_ref_list(struct ref_list *list)
166{
167 struct ref_list *next;
168 for ( ; list; list = next) {
169 next = list->next;
170 free(list);
171 }
172}
173
174static void invalidate_cached_refs(void)
e1e22e37 175{
5e290ff7
JH
176 struct cached_refs *ca = &cached_refs;
177
178 if (ca->did_loose && ca->loose)
179 free_ref_list(ca->loose);
180 if (ca->did_packed && ca->packed)
181 free_ref_list(ca->packed);
182 ca->loose = ca->packed = NULL;
183 ca->did_loose = ca->did_packed = 0;
184}
e1e22e37 185
f4204ab9
JH
186static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
187{
188 struct ref_list *list = NULL;
189 struct ref_list *last = NULL;
190 char refline[PATH_MAX];
191 int flag = REF_ISPACKED;
192
193 while (fgets(refline, sizeof(refline), f)) {
194 unsigned char sha1[20];
195 const char *name;
196 static const char header[] = "# pack-refs with:";
197
198 if (!strncmp(refline, header, sizeof(header)-1)) {
199 const char *traits = refline + sizeof(header) - 1;
200 if (strstr(traits, " peeled "))
201 flag |= REF_KNOWS_PEELED;
202 /* perhaps other traits later as well */
203 continue;
204 }
205
206 name = parse_ref_line(refline, sha1);
207 if (name) {
208 list = add_ref(name, sha1, flag, list, &last);
209 continue;
210 }
211 if (last &&
212 refline[0] == '^' &&
213 strlen(refline) == 42 &&
214 refline[41] == '\n' &&
215 !get_sha1_hex(refline + 1, sha1))
216 hashcpy(last->peeled, sha1);
217 }
c774aab9 218 cached_refs->packed = sort_ref_list(list);
f4204ab9
JH
219}
220
e142a3c6
DB
221void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
222{
223 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
224}
225
226void clear_extra_refs(void)
227{
228 free_ref_list(extra_refs);
229 extra_refs = NULL;
230}
231
5e290ff7
JH
232static struct ref_list *get_packed_refs(void)
233{
234 if (!cached_refs.did_packed) {
e1e22e37 235 FILE *f = fopen(git_path("packed-refs"), "r");
f4204ab9 236 cached_refs.packed = NULL;
e1e22e37 237 if (f) {
f4204ab9 238 read_packed_refs(f, &cached_refs);
e1e22e37 239 fclose(f);
e1e22e37 240 }
5e290ff7 241 cached_refs.did_packed = 1;
e1e22e37 242 }
5e290ff7 243 return cached_refs.packed;
e1e22e37
LT
244}
245
246static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
247{
248 DIR *dir = opendir(git_path("%s", base));
249
250 if (dir) {
251 struct dirent *de;
252 int baselen = strlen(base);
ed378ec7 253 char *ref = xmalloc(baselen + 257);
e1e22e37 254
ed378ec7 255 memcpy(ref, base, baselen);
e1e22e37 256 if (baselen && base[baselen-1] != '/')
ed378ec7 257 ref[baselen++] = '/';
e1e22e37
LT
258
259 while ((de = readdir(dir)) != NULL) {
260 unsigned char sha1[20];
261 struct stat st;
8da19775 262 int flag;
e1e22e37
LT
263 int namelen;
264
265 if (de->d_name[0] == '.')
266 continue;
267 namelen = strlen(de->d_name);
268 if (namelen > 255)
269 continue;
270 if (has_extension(de->d_name, ".lock"))
271 continue;
ed378ec7
LT
272 memcpy(ref + baselen, de->d_name, namelen+1);
273 if (stat(git_path("%s", ref), &st) < 0)
e1e22e37
LT
274 continue;
275 if (S_ISDIR(st.st_mode)) {
ed378ec7 276 list = get_ref_dir(ref, list);
e1e22e37
LT
277 continue;
278 }
e01de1c9 279 if (!resolve_ref(ref, sha1, 1, &flag)) {
f8948e2f 280 hashclr(sha1);
e01de1c9
JH
281 flag |= REF_BROKEN;
282 }
f4204ab9 283 list = add_ref(ref, sha1, flag, list, NULL);
e1e22e37 284 }
ed378ec7 285 free(ref);
e1e22e37
LT
286 closedir(dir);
287 }
c774aab9 288 return sort_ref_list(list);
e1e22e37
LT
289}
290
f8948e2f 291struct warn_if_dangling_data {
3cf6134a 292 FILE *fp;
f8948e2f
JH
293 const char *refname;
294 const char *msg_fmt;
295};
296
297static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
298 int flags, void *cb_data)
299{
300 struct warn_if_dangling_data *d = cb_data;
301 const char *resolves_to;
302 unsigned char junk[20];
303
304 if (!(flags & REF_ISSYMREF))
305 return 0;
306
307 resolves_to = resolve_ref(refname, junk, 0, NULL);
308 if (!resolves_to || strcmp(resolves_to, d->refname))
309 return 0;
310
3cf6134a 311 fprintf(d->fp, d->msg_fmt, refname);
f8948e2f
JH
312 return 0;
313}
314
3cf6134a 315void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
f8948e2f 316{
66dbfd55
GV
317 struct warn_if_dangling_data data;
318
319 data.fp = fp;
320 data.refname = refname;
321 data.msg_fmt = msg_fmt;
f8948e2f
JH
322 for_each_rawref(warn_if_dangling_symref, &data);
323}
324
e1e22e37
LT
325static struct ref_list *get_loose_refs(void)
326{
5e290ff7
JH
327 if (!cached_refs.did_loose) {
328 cached_refs.loose = get_ref_dir("refs", NULL);
329 cached_refs.did_loose = 1;
e1e22e37 330 }
5e290ff7 331 return cached_refs.loose;
e1e22e37
LT
332}
333
ca8db142
LT
334/* We allow "recursive" symbolic refs. Only within reason, though */
335#define MAXDEPTH 5
0ebde32c
LT
336#define MAXREFLEN (1024)
337
338static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
339{
340 FILE *f;
341 struct cached_refs refs;
342 struct ref_list *ref;
343 int retval;
344
345 strcpy(name + pathlen, "packed-refs");
346 f = fopen(name, "r");
347 if (!f)
348 return -1;
349 read_packed_refs(f, &refs);
350 fclose(f);
351 ref = refs.packed;
352 retval = -1;
353 while (ref) {
354 if (!strcmp(ref->name, refname)) {
355 retval = 0;
356 memcpy(result, ref->sha1, 20);
357 break;
358 }
359 ref = ref->next;
360 }
361 free_ref_list(refs.packed);
362 return retval;
363}
364
365static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
366{
367 int fd, len = strlen(refname);
368 char buffer[128], *p;
369
370 if (recursion > MAXDEPTH || len > MAXREFLEN)
371 return -1;
372 memcpy(name + pathlen, refname, len+1);
373 fd = open(name, O_RDONLY);
374 if (fd < 0)
375 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
376
377 len = read(fd, buffer, sizeof(buffer)-1);
378 close(fd);
379 if (len < 0)
380 return -1;
381 while (len && isspace(buffer[len-1]))
382 len--;
383 buffer[len] = 0;
384
385 /* Was it a detached head or an old-fashioned symlink? */
386 if (!get_sha1_hex(buffer, result))
387 return 0;
388
389 /* Symref? */
390 if (strncmp(buffer, "ref:", 4))
391 return -1;
392 p = buffer + 4;
393 while (isspace(*p))
394 p++;
395
396 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
397}
398
399int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
400{
401 int len = strlen(path), retval;
402 char *gitdir;
842abf06 403 const char *tmp;
0ebde32c
LT
404
405 while (len && path[len-1] == '/')
406 len--;
407 if (!len)
408 return -1;
409 gitdir = xmalloc(len + MAXREFLEN + 8);
410 memcpy(gitdir, path, len);
842abf06
LH
411 memcpy(gitdir + len, "/.git", 6);
412 len += 5;
413
414 tmp = read_gitfile_gently(gitdir);
415 if (tmp) {
416 free(gitdir);
417 len = strlen(tmp);
418 gitdir = xmalloc(len + MAXREFLEN + 3);
419 memcpy(gitdir, tmp, len);
420 }
421 gitdir[len] = '/';
422 gitdir[++len] = '\0';
423 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
0ebde32c
LT
424 free(gitdir);
425 return retval;
426}
ca8db142 427
4886b89f
CC
428/*
429 * If the "reading" argument is set, this function finds out what _object_
430 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
431 * has to exist, and if it is symbolic, it has to point at an existing ref,
432 * because the "read" goes through the symref to the ref it points at.
433 *
434 * The access that is not "reading" may often be "writing", but does not
435 * have to; it can be merely checking _where it leads to_. If it is a
436 * prelude to "writing" to the ref, a write to a symref that points at
437 * yet-to-be-born ref will create the real ref pointed by the symref.
438 * reading=0 allows the caller to check where such a symref leads to.
439 */
8da19775 440const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
8a65ff76 441{
0104ca09
HO
442 int depth = MAXDEPTH;
443 ssize_t len;
a876ed83 444 char buffer[256];
ed378ec7 445 static char ref_buffer[256];
ca8db142 446
8da19775
JH
447 if (flag)
448 *flag = 0;
449
a876ed83 450 for (;;) {
958a4789 451 char path[PATH_MAX];
a876ed83
JH
452 struct stat st;
453 char *buf;
454 int fd;
8a65ff76 455
a876ed83
JH
456 if (--depth < 0)
457 return NULL;
ca8db142 458
958a4789 459 git_snpath(path, sizeof(path), "%s", ref);
4886b89f 460 /* Special case: non-existing file. */
a876ed83 461 if (lstat(path, &st) < 0) {
434cd0cd
LT
462 struct ref_list *list = get_packed_refs();
463 while (list) {
f4204ab9 464 if (!strcmp(ref, list->name)) {
434cd0cd 465 hashcpy(sha1, list->sha1);
8da19775
JH
466 if (flag)
467 *flag |= REF_ISPACKED;
434cd0cd
LT
468 return ref;
469 }
470 list = list->next;
471 }
a876ed83
JH
472 if (reading || errno != ENOENT)
473 return NULL;
e702496e 474 hashclr(sha1);
ed378ec7 475 return ref;
a876ed83 476 }
ca8db142 477
a876ed83
JH
478 /* Follow "normalized" - ie "refs/.." symlinks by hand */
479 if (S_ISLNK(st.st_mode)) {
480 len = readlink(path, buffer, sizeof(buffer)-1);
481 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
ed378ec7
LT
482 buffer[len] = 0;
483 strcpy(ref_buffer, buffer);
484 ref = ref_buffer;
8da19775
JH
485 if (flag)
486 *flag |= REF_ISSYMREF;
a876ed83
JH
487 continue;
488 }
ca8db142 489 }
a876ed83 490
7a21632f
DS
491 /* Is it a directory? */
492 if (S_ISDIR(st.st_mode)) {
493 errno = EISDIR;
494 return NULL;
495 }
496
a876ed83
JH
497 /*
498 * Anything else, just open it and try to use it as
499 * a ref
500 */
501 fd = open(path, O_RDONLY);
502 if (fd < 0)
503 return NULL;
93d26e4c 504 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83
JH
505 close(fd);
506
507 /*
508 * Is it a symbolic ref?
509 */
510 if (len < 4 || memcmp("ref:", buffer, 4))
511 break;
512 buf = buffer + 4;
513 len -= 4;
514 while (len && isspace(*buf))
515 buf++, len--;
516 while (len && isspace(buf[len-1]))
ed378ec7
LT
517 len--;
518 buf[len] = 0;
519 memcpy(ref_buffer, buf, len + 1);
520 ref = ref_buffer;
8da19775
JH
521 if (flag)
522 *flag |= REF_ISSYMREF;
8a65ff76 523 }
a876ed83
JH
524 if (len < 40 || get_sha1_hex(buffer, sha1))
525 return NULL;
ed378ec7 526 return ref;
a876ed83
JH
527}
528
d08bae7e
IL
529/* The argument to filter_refs */
530struct ref_filter {
531 const char *pattern;
532 each_ref_fn *fn;
533 void *cb_data;
534};
535
ed378ec7 536int read_ref(const char *ref, unsigned char *sha1)
a876ed83 537{
8da19775 538 if (resolve_ref(ref, sha1, 1, NULL))
a876ed83
JH
539 return 0;
540 return -1;
8a65ff76
LT
541}
542
f8948e2f 543#define DO_FOR_EACH_INCLUDE_BROKEN 01
ef06b918 544static int do_one_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 545 int flags, void *cb_data, struct ref_list *entry)
ef06b918
JH
546{
547 if (strncmp(base, entry->name, trim))
548 return 0;
e01de1c9 549
f8948e2f 550 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
e01de1c9
JH
551 if (entry->flag & REF_BROKEN)
552 return 0; /* ignore dangling symref */
f8948e2f
JH
553 if (!has_sha1_file(entry->sha1)) {
554 error("%s does not point to a valid object!", entry->name);
555 return 0;
556 }
ef06b918 557 }
0ae91be0 558 current_ref = entry;
ef06b918
JH
559 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
560}
561
d08bae7e
IL
562static int filter_refs(const char *ref, const unsigned char *sha, int flags,
563 void *data)
564{
565 struct ref_filter *filter = (struct ref_filter *)data;
566 if (fnmatch(filter->pattern, ref, 0))
567 return 0;
568 return filter->fn(ref, sha, flags, filter->cb_data);
569}
570
cf0adba7
JH
571int peel_ref(const char *ref, unsigned char *sha1)
572{
573 int flag;
574 unsigned char base[20];
575 struct object *o;
576
0ae91be0
SP
577 if (current_ref && (current_ref->name == ref
578 || !strcmp(current_ref->name, ref))) {
579 if (current_ref->flag & REF_KNOWS_PEELED) {
580 hashcpy(sha1, current_ref->peeled);
581 return 0;
582 }
583 hashcpy(base, current_ref->sha1);
584 goto fallback;
585 }
586
cf0adba7
JH
587 if (!resolve_ref(ref, base, 1, &flag))
588 return -1;
589
590 if ((flag & REF_ISPACKED)) {
591 struct ref_list *list = get_packed_refs();
cf0adba7
JH
592
593 while (list) {
f4204ab9
JH
594 if (!strcmp(list->name, ref)) {
595 if (list->flag & REF_KNOWS_PEELED) {
596 hashcpy(sha1, list->peeled);
597 return 0;
598 }
599 /* older pack-refs did not leave peeled ones */
600 break;
cf0adba7
JH
601 }
602 list = list->next;
603 }
cf0adba7
JH
604 }
605
0ae91be0 606fallback:
cf0adba7 607 o = parse_object(base);
8c87dc77 608 if (o && o->type == OBJ_TAG) {
cf0adba7
JH
609 o = deref_tag(o, ref, 0);
610 if (o) {
611 hashcpy(sha1, o->sha1);
612 return 0;
613 }
614 }
615 return -1;
616}
617
8da19775 618static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 619 int flags, void *cb_data)
8a65ff76 620{
0ae91be0 621 int retval = 0;
e1e22e37
LT
622 struct ref_list *packed = get_packed_refs();
623 struct ref_list *loose = get_loose_refs();
8a65ff76 624
e142a3c6
DB
625 struct ref_list *extra;
626
627 for (extra = extra_refs; extra; extra = extra->next)
f8948e2f 628 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
e142a3c6 629
e1e22e37
LT
630 while (packed && loose) {
631 struct ref_list *entry;
632 int cmp = strcmp(packed->name, loose->name);
633 if (!cmp) {
634 packed = packed->next;
635 continue;
6cada6a9 636 }
e1e22e37
LT
637 if (cmp > 0) {
638 entry = loose;
639 loose = loose->next;
640 } else {
641 entry = packed;
642 packed = packed->next;
643 }
f8948e2f 644 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
e1e22e37 645 if (retval)
0ae91be0 646 goto end_each;
e1e22e37 647 }
8a65ff76 648
ef06b918 649 for (packed = packed ? packed : loose; packed; packed = packed->next) {
f8948e2f 650 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
ef06b918 651 if (retval)
0ae91be0 652 goto end_each;
8a65ff76 653 }
0ae91be0
SP
654
655end_each:
656 current_ref = NULL;
657 return retval;
8a65ff76
LT
658}
659
cb5d709f 660int head_ref(each_ref_fn fn, void *cb_data)
723c31fe
LT
661{
662 unsigned char sha1[20];
8da19775
JH
663 int flag;
664
665 if (resolve_ref("HEAD", sha1, 1, &flag))
666 return fn("HEAD", sha1, flag, cb_data);
2f34ba32 667 return 0;
723c31fe
LT
668}
669
cb5d709f 670int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 671{
f8948e2f 672 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
a62be77f
SE
673}
674
2a8177b6
CC
675int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
676{
677 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
678}
679
cb5d709f 680int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 681{
2a8177b6 682 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
683}
684
cb5d709f 685int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 686{
2a8177b6 687 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
688}
689
cb5d709f 690int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 691{
2a8177b6 692 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
693}
694
29268700
CC
695int for_each_replace_ref(each_ref_fn fn, void *cb_data)
696{
697 return do_for_each_ref("refs/replace/", fn, 13, 0, cb_data);
698}
699
b09fe971
IL
700int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
701 const char *prefix, void *cb_data)
d08bae7e
IL
702{
703 struct strbuf real_pattern = STRBUF_INIT;
704 struct ref_filter filter;
d08bae7e
IL
705 int ret;
706
b09fe971 707 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 708 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
709 else if (prefix)
710 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
711 strbuf_addstr(&real_pattern, pattern);
712
894a9d33 713 if (!has_glob_specials(pattern)) {
9517e6b8 714 /* Append implied '/' '*' if not present. */
d08bae7e
IL
715 if (real_pattern.buf[real_pattern.len - 1] != '/')
716 strbuf_addch(&real_pattern, '/');
717 /* No need to check for '*', there is none. */
718 strbuf_addch(&real_pattern, '*');
719 }
720
721 filter.pattern = real_pattern.buf;
722 filter.fn = fn;
723 filter.cb_data = cb_data;
724 ret = for_each_ref(filter_refs, &filter);
725
726 strbuf_release(&real_pattern);
727 return ret;
728}
729
b09fe971
IL
730int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
731{
732 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
733}
734
f8948e2f
JH
735int for_each_rawref(each_ref_fn fn, void *cb_data)
736{
737 return do_for_each_ref("refs/", fn, 0,
738 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
739}
740
03feddd6
JH
741/*
742 * Make sure "ref" is something reasonable to have under ".git/refs/";
743 * We do not like it if:
744 *
745 * - any path component of it begins with ".", or
746 * - it has double dots "..", or
747 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
748 * - it ends with a "/".
3e262b95 749 * - it ends with ".lock"
a4c2e699 750 * - it contains a "\" (backslash)
03feddd6
JH
751 */
752
753static inline int bad_ref_char(int ch)
754{
8558fd9e 755 if (((unsigned) ch) <= ' ' ||
a4c2e699 756 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
8558fd9e
DB
757 return 1;
758 /* 2.13 Pattern Matching Notation */
759 if (ch == '?' || ch == '[') /* Unsupported */
760 return 1;
761 if (ch == '*') /* Supported at the end */
762 return 2;
763 return 0;
03feddd6
JH
764}
765
95fc7512
DB
766int check_ref_format(const char *ref)
767{
cbdffe40 768 int ch, level, bad_type, last;
abd2bde7 769 int ret = CHECK_REF_FORMAT_OK;
03feddd6
JH
770 const char *cp = ref;
771
772 level = 0;
773 while (1) {
774 while ((ch = *cp++) == '/')
775 ; /* tolerate duplicated slashes */
776 if (!ch)
5f7b202a
JH
777 /* should not end with slashes */
778 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
779
780 /* we are at the beginning of the path component */
8558fd9e 781 if (ch == '.')
5f7b202a 782 return CHECK_REF_FORMAT_ERROR;
8558fd9e
DB
783 bad_type = bad_ref_char(ch);
784 if (bad_type) {
abd2bde7
DB
785 if (bad_type == 2 && (!*cp || *cp == '/') &&
786 ret == CHECK_REF_FORMAT_OK)
787 ret = CHECK_REF_FORMAT_WILDCARD;
788 else
789 return CHECK_REF_FORMAT_ERROR;
8558fd9e 790 }
03feddd6 791
cbdffe40 792 last = ch;
03feddd6
JH
793 /* scan the rest of the path component */
794 while ((ch = *cp++) != 0) {
8558fd9e 795 bad_type = bad_ref_char(ch);
cbdffe40 796 if (bad_type)
08fbdb30 797 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
798 if (ch == '/')
799 break;
cbdffe40
JH
800 if (last == '.' && ch == '.')
801 return CHECK_REF_FORMAT_ERROR;
802 if (last == '@' && ch == '{')
5f7b202a 803 return CHECK_REF_FORMAT_ERROR;
cbdffe40 804 last = ch;
03feddd6
JH
805 }
806 level++;
807 if (!ch) {
cbdffe40
JH
808 if (ref <= cp - 2 && cp[-2] == '.')
809 return CHECK_REF_FORMAT_ERROR;
03feddd6 810 if (level < 2)
5f7b202a 811 return CHECK_REF_FORMAT_ONELEVEL;
3e262b95
SP
812 if (has_extension(ref, ".lock"))
813 return CHECK_REF_FORMAT_ERROR;
abd2bde7 814 return ret;
03feddd6
JH
815 }
816 }
95fc7512
DB
817}
818
4577e483 819const char *prettify_refname(const char *name)
a9c37a72 820{
a9c37a72
DB
821 return name + (
822 !prefixcmp(name, "refs/heads/") ? 11 :
823 !prefixcmp(name, "refs/tags/") ? 10 :
824 !prefixcmp(name, "refs/remotes/") ? 13 :
825 0);
826}
827
79803322
SP
828const char *ref_rev_parse_rules[] = {
829 "%.*s",
830 "refs/%.*s",
831 "refs/tags/%.*s",
832 "refs/heads/%.*s",
833 "refs/remotes/%.*s",
834 "refs/remotes/%.*s/HEAD",
835 NULL
836};
837
605b4978
SP
838const char *ref_fetch_rules[] = {
839 "%.*s",
840 "refs/%.*s",
841 "refs/heads/%.*s",
842 NULL
843};
844
79803322
SP
845int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
846{
847 const char **p;
848 const int abbrev_name_len = strlen(abbrev_name);
849
850 for (p = rules; *p; p++) {
851 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
852 return 1;
853 }
854 }
855
856 return 0;
857}
858
e5f38ec3 859static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
860 const unsigned char *old_sha1, int mustexist)
861{
8da19775 862 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 863 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
864 unlock_ref(lock);
865 return NULL;
866 }
a89fccd2 867 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 868 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
869 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
870 unlock_ref(lock);
871 return NULL;
872 }
873 return lock;
874}
875
7155b727 876static int remove_empty_directories(const char *file)
bc7127ef
JH
877{
878 /* we want to create a file but there is a directory there;
879 * if that is an empty directory (or a directory that contains
880 * only empty directories), remove them.
881 */
7155b727
JS
882 struct strbuf path;
883 int result;
bc7127ef 884
7155b727
JS
885 strbuf_init(&path, 20);
886 strbuf_addstr(&path, file);
887
a0f4afbe 888 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
889
890 strbuf_release(&path);
891
892 return result;
bc7127ef
JH
893}
894
c976d415
LH
895static int is_refname_available(const char *ref, const char *oldref,
896 struct ref_list *list, int quiet)
897{
898 int namlen = strlen(ref); /* e.g. 'foo/bar' */
899 while (list) {
900 /* list->name could be 'foo' or 'foo/bar/baz' */
901 if (!oldref || strcmp(oldref, list->name)) {
902 int len = strlen(list->name);
903 int cmplen = (namlen < len) ? namlen : len;
904 const char *lead = (namlen < len) ? list->name : ref;
905 if (!strncmp(ref, list->name, cmplen) &&
906 lead[cmplen] == '/') {
907 if (!quiet)
908 error("'%s' exists; cannot create '%s'",
909 list->name, ref);
910 return 0;
911 }
912 }
913 list = list->next;
914 }
915 return 1;
916}
917
68db31cc 918static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
4bd18c43 919{
434cd0cd 920 char *ref_file;
ed378ec7 921 const char *orig_ref = ref;
4bd18c43 922 struct ref_lock *lock;
5cc3cef9 923 int last_errno = 0;
acd3b9ec 924 int type, lflags;
4431fcc4 925 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 926 int missing = 0;
4bd18c43
SP
927
928 lock = xcalloc(1, sizeof(struct ref_lock));
929 lock->lock_fd = -1;
930
68db31cc 931 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
bc7127ef
JH
932 if (!ref && errno == EISDIR) {
933 /* we are trying to lock foo but we used to
934 * have foo/bar which now does not exist;
935 * it is normal for the empty directory 'foo'
936 * to remain.
937 */
938 ref_file = git_path("%s", orig_ref);
5cc3cef9
JH
939 if (remove_empty_directories(ref_file)) {
940 last_errno = errno;
941 error("there are still refs under '%s'", orig_ref);
942 goto error_return;
943 }
68db31cc 944 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
bc7127ef 945 }
68db31cc
SV
946 if (type_p)
947 *type_p = type;
ed378ec7 948 if (!ref) {
5cc3cef9 949 last_errno = errno;
818f477c 950 error("unable to resolve reference %s: %s",
ed378ec7 951 orig_ref, strerror(errno));
5cc3cef9 952 goto error_return;
4bd18c43 953 }
5bdd8d4a 954 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
955 /* When the ref did not exist and we are creating it,
956 * make sure there is no existing ref that is packed
957 * whose name begins with our refname, nor a ref whose
958 * name is a proper prefix of our refname.
959 */
5bdd8d4a 960 if (missing &&
f475e08e
JK
961 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
962 last_errno = ENOTDIR;
c976d415 963 goto error_return;
f475e08e 964 }
22a3844e 965
c33d5174 966 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 967
acd3b9ec
JH
968 lflags = LOCK_DIE_ON_ERROR;
969 if (flags & REF_NODEREF) {
68db31cc 970 ref = orig_ref;
acd3b9ec
JH
971 lflags |= LOCK_NODEREF;
972 }
434cd0cd 973 lock->ref_name = xstrdup(ref);
1655707c 974 lock->orig_ref_name = xstrdup(orig_ref);
7c1a278d 975 ref_file = git_path("%s", ref);
5bdd8d4a 976 if (missing)
68db31cc
SV
977 lock->force_write = 1;
978 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
979 lock->force_write = 1;
4bd18c43 980
5cc3cef9
JH
981 if (safe_create_leading_directories(ref_file)) {
982 last_errno = errno;
983 error("unable to create directory for %s", ref_file);
984 goto error_return;
985 }
4bd18c43 986
acd3b9ec 987 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 988 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
989
990 error_return:
991 unlock_ref(lock);
992 errno = last_errno;
993 return NULL;
4bd18c43
SP
994}
995
4431fcc4 996struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
95fc7512 997{
53cce84c 998 char refpath[PATH_MAX];
95fc7512 999 if (check_ref_format(ref))
4bd18c43 1000 return NULL;
53cce84c 1001 strcpy(refpath, mkpath("refs/%s", ref));
68db31cc 1002 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1003}
1004
68db31cc 1005struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
4bd18c43 1006{
5f7b202a 1007 switch (check_ref_format(ref)) {
5f7b202a 1008 default:
257f3020
JH
1009 return NULL;
1010 case 0:
1011 case CHECK_REF_FORMAT_ONELEVEL:
5f7b202a
JH
1012 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1013 }
c0277d15
JH
1014}
1015
26a063a1
JH
1016static struct lock_file packlock;
1017
c0277d15
JH
1018static int repack_without_ref(const char *refname)
1019{
1020 struct ref_list *list, *packed_ref_list;
1021 int fd;
1022 int found = 0;
c0277d15
JH
1023
1024 packed_ref_list = get_packed_refs();
1025 for (list = packed_ref_list; list; list = list->next) {
1026 if (!strcmp(refname, list->name)) {
1027 found = 1;
1028 break;
1029 }
1030 }
1031 if (!found)
1032 return 0;
c0277d15 1033 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1b018fd9
MV
1034 if (fd < 0) {
1035 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1036 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1037 }
c0277d15
JH
1038
1039 for (list = packed_ref_list; list; list = list->next) {
1040 char line[PATH_MAX + 100];
1041 int len;
1042
1043 if (!strcmp(refname, list->name))
1044 continue;
1045 len = snprintf(line, sizeof(line), "%s %s\n",
1046 sha1_to_hex(list->sha1), list->name);
1047 /* this should not happen but just being defensive */
1048 if (len > sizeof(line))
1049 die("too long a refname '%s'", list->name);
1050 write_or_die(fd, line, len);
1051 }
1052 return commit_lock_file(&packlock);
1053}
1054
eca35a25 1055int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1056{
1057 struct ref_lock *lock;
eca35a25 1058 int err, i = 0, ret = 0, flag = 0;
c0277d15 1059
68db31cc 1060 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1061 if (!lock)
1062 return 1;
045a476f 1063 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1064 /* loose */
eca35a25
MV
1065 const char *path;
1066
1067 if (!(delopt & REF_NODEREF)) {
1068 i = strlen(lock->lk->filename) - 5; /* .lock */
1069 lock->lk->filename[i] = 0;
1070 path = lock->lk->filename;
1071 } else {
9db56f71 1072 path = git_path("%s", refname);
eca35a25 1073 }
691f1a28
AR
1074 err = unlink_or_warn(path);
1075 if (err && errno != ENOENT)
c0277d15 1076 ret = 1;
691f1a28 1077
eca35a25
MV
1078 if (!(delopt & REF_NODEREF))
1079 lock->lk->filename[i] = '.';
c0277d15
JH
1080 }
1081 /* removing the loose one could have resurrected an earlier
1082 * packed one. Also, if it was not loose we need to repack
1083 * without it.
1084 */
1085 ret |= repack_without_ref(refname);
1086
691f1a28 1087 unlink_or_warn(git_path("logs/%s", lock->ref_name));
c0277d15
JH
1088 invalidate_cached_refs();
1089 unlock_ref(lock);
1090 return ret;
4bd18c43
SP
1091}
1092
678d0f4c 1093int rename_ref(const char *oldref, const char *newref, const char *logmsg)
c976d415
LH
1094{
1095 static const char renamed_ref[] = "RENAMED-REF";
1096 unsigned char sha1[20], orig_sha1[20];
1097 int flag = 0, logmoved = 0;
1098 struct ref_lock *lock;
c976d415 1099 struct stat loginfo;
16c2bfbb 1100 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
eca35a25 1101 const char *symref = NULL;
c976d415 1102
450d4c0f 1103 if (log && S_ISLNK(loginfo.st_mode))
c976d415
LH
1104 return error("reflog for %s is a symlink", oldref);
1105
eca35a25
MV
1106 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1107 if (flag & REF_ISSYMREF)
fa58186c
MV
1108 return error("refname %s is a symbolic ref, renaming it is not supported",
1109 oldref);
eca35a25 1110 if (!symref)
c976d415
LH
1111 return error("refname %s not found", oldref);
1112
1113 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1114 return 1;
1115
1116 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1117 return 1;
1118
68db31cc 1119 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
c976d415
LH
1120 if (!lock)
1121 return error("unable to lock %s", renamed_ref);
1122 lock->force_write = 1;
678d0f4c 1123 if (write_ref_sha1(lock, orig_sha1, logmsg))
c976d415
LH
1124 return error("unable to save current sha1 in %s", renamed_ref);
1125
1126 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1127 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1128 oldref, strerror(errno));
1129
eca35a25 1130 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
c976d415
LH
1131 error("unable to delete old %s", oldref);
1132 goto rollback;
1133 }
1134
eca35a25 1135 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
c976d415
LH
1136 if (errno==EISDIR) {
1137 if (remove_empty_directories(git_path("%s", newref))) {
1138 error("Directory not empty: %s", newref);
1139 goto rollback;
1140 }
1141 } else {
1142 error("unable to delete existing %s", newref);
1143 goto rollback;
1144 }
1145 }
1146
1147 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1148 error("unable to create directory for %s", newref);
1149 goto rollback;
1150 }
1151
1152 retry:
1153 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
d9e74d57
JR
1154 if (errno==EISDIR || errno==ENOTDIR) {
1155 /*
1156 * rename(a, b) when b is an existing
1157 * directory ought to result in ISDIR, but
1158 * Solaris 5.8 gives ENOTDIR. Sheesh.
1159 */
c976d415
LH
1160 if (remove_empty_directories(git_path("logs/%s", newref))) {
1161 error("Directory not empty: logs/%s", newref);
1162 goto rollback;
1163 }
1164 goto retry;
1165 } else {
1166 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1167 newref, strerror(errno));
1168 goto rollback;
1169 }
1170 }
1171 logmoved = log;
1172
68db31cc 1173 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
c976d415
LH
1174 if (!lock) {
1175 error("unable to lock %s for update", newref);
1176 goto rollback;
1177 }
c976d415
LH
1178 lock->force_write = 1;
1179 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1180 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
c976d415
LH
1181 error("unable to write current sha1 into %s", newref);
1182 goto rollback;
1183 }
1184
1185 return 0;
1186
1187 rollback:
68db31cc 1188 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
c976d415
LH
1189 if (!lock) {
1190 error("unable to lock %s for rollback", oldref);
1191 goto rollbacklog;
1192 }
1193
1194 lock->force_write = 1;
1195 flag = log_all_ref_updates;
1196 log_all_ref_updates = 0;
1197 if (write_ref_sha1(lock, orig_sha1, NULL))
1198 error("unable to write current sha1 into %s", oldref);
1199 log_all_ref_updates = flag;
1200
1201 rollbacklog:
1202 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1203 error("unable to restore logfile %s from %s: %s",
1204 oldref, newref, strerror(errno));
1205 if (!logmoved && log &&
1206 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1207 error("unable to restore logfile %s from tmp-renamed-log: %s",
1208 oldref, strerror(errno));
1209
1210 return 1;
1211}
1212
435fc852 1213int close_ref(struct ref_lock *lock)
b531394d
BC
1214{
1215 if (close_lock_file(lock->lk))
1216 return -1;
1217 lock->lock_fd = -1;
1218 return 0;
1219}
1220
435fc852 1221int commit_ref(struct ref_lock *lock)
b531394d
BC
1222{
1223 if (commit_lock_file(lock->lk))
1224 return -1;
1225 lock->lock_fd = -1;
1226 return 0;
1227}
1228
e5f38ec3 1229void unlock_ref(struct ref_lock *lock)
4bd18c43 1230{
4ed7cd3a
BC
1231 /* Do not free lock->lk -- atexit() still looks at them */
1232 if (lock->lk)
1233 rollback_lock_file(lock->lk);
434cd0cd 1234 free(lock->ref_name);
1655707c 1235 free(lock->orig_ref_name);
4bd18c43
SP
1236 free(lock);
1237}
1238
0ec29a47
JH
1239/*
1240 * copy the reflog message msg to buf, which has been allocated sufficiently
1241 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1242 * because reflog file is one line per entry.
1243 */
1244static int copy_msg(char *buf, const char *msg)
1245{
1246 char *cp = buf;
1247 char c;
1248 int wasspace = 1;
1249
1250 *cp++ = '\t';
1251 while ((c = *msg++)) {
1252 if (wasspace && isspace(c))
1253 continue;
1254 wasspace = isspace(c);
1255 if (wasspace)
1256 c = ' ';
1257 *cp++ = c;
1258 }
1259 while (buf < cp && isspace(cp[-1]))
1260 cp--;
1261 *cp++ = '\n';
1262 return cp - buf;
1263}
1264
157aaea5 1265int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
6de08ae6 1266{
859c3017 1267 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1268
157aaea5 1269 git_snpath(logfile, bufsize, "logs/%s", ref_name);
4057deb5 1270 if (log_all_ref_updates &&
cc44c765
JH
1271 (!prefixcmp(ref_name, "refs/heads/") ||
1272 !prefixcmp(ref_name, "refs/remotes/") ||
b2e256b0 1273 !prefixcmp(ref_name, "refs/notes/") ||
bd104db1 1274 !strcmp(ref_name, "HEAD"))) {
157aaea5 1275 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1276 return error("unable to create directory for %s",
157aaea5 1277 logfile);
6de08ae6
SP
1278 oflags |= O_CREAT;
1279 }
1280
157aaea5 1281 logfd = open(logfile, oflags, 0666);
6de08ae6 1282 if (logfd < 0) {
1974bf62 1283 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1284 return 0;
3b463c3f
JH
1285
1286 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1287 if (remove_empty_directories(logfile)) {
3b463c3f 1288 return error("There are still logs under '%s'",
157aaea5 1289 logfile);
3b463c3f 1290 }
157aaea5 1291 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1292 }
1293
1294 if (logfd < 0)
1295 return error("Unable to append to %s: %s",
157aaea5 1296 logfile, strerror(errno));
6de08ae6
SP
1297 }
1298
157aaea5 1299 adjust_shared_perm(logfile);
859c3017
EM
1300 close(logfd);
1301 return 0;
1302}
443b92b6 1303
859c3017
EM
1304static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1305 const unsigned char *new_sha1, const char *msg)
1306{
1307 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1308 unsigned maxlen, len;
1309 int msglen;
157aaea5 1310 char log_file[PATH_MAX];
859c3017
EM
1311 char *logrec;
1312 const char *committer;
1313
1314 if (log_all_ref_updates < 0)
1315 log_all_ref_updates = !is_bare_repository();
1316
157aaea5 1317 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
859c3017
EM
1318 if (result)
1319 return result;
1320
1321 logfd = open(log_file, oflags);
1322 if (logfd < 0)
1323 return 0;
0ec29a47 1324 msglen = msg ? strlen(msg) : 0;
774751a8 1325 committer = git_committer_info(0);
8ac65937
JH
1326 maxlen = strlen(committer) + msglen + 100;
1327 logrec = xmalloc(maxlen);
1328 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1329 sha1_to_hex(old_sha1),
1330 sha1_to_hex(new_sha1),
8ac65937
JH
1331 committer);
1332 if (msglen)
0ec29a47 1333 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1334 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1335 free(logrec);
91c8d590 1336 if (close(logfd) != 0 || written != len)
9a13f0b7 1337 return error("Unable to append to %s", log_file);
6de08ae6
SP
1338 return 0;
1339}
1340
c3b0dec5
LT
1341static int is_branch(const char *refname)
1342{
1343 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1344}
1345
4bd18c43
SP
1346int write_ref_sha1(struct ref_lock *lock,
1347 const unsigned char *sha1, const char *logmsg)
1348{
1349 static char term = '\n';
c3b0dec5 1350 struct object *o;
4bd18c43
SP
1351
1352 if (!lock)
95fc7512 1353 return -1;
a89fccd2 1354 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1355 unlock_ref(lock);
1356 return 0;
95fc7512 1357 }
c3b0dec5
LT
1358 o = parse_object(sha1);
1359 if (!o) {
1360 error("Trying to write ref %s with nonexistant object %s",
1361 lock->ref_name, sha1_to_hex(sha1));
1362 unlock_ref(lock);
1363 return -1;
1364 }
1365 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1366 error("Trying to write non-commit object %s to branch %s",
1367 sha1_to_hex(sha1), lock->ref_name);
1368 unlock_ref(lock);
1369 return -1;
1370 }
93822c22
AW
1371 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1372 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1373 || close_ref(lock) < 0) {
c33d5174 1374 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1375 unlock_ref(lock);
1376 return -1;
1377 }
5e290ff7 1378 invalidate_cached_refs();
bd104db1
NP
1379 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1380 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1381 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1382 unlock_ref(lock);
1383 return -1;
1384 }
605fac8b
NP
1385 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1386 /*
1387 * Special hack: If a branch is updated directly and HEAD
1388 * points to it (may happen on the remote side of a push
1389 * for example) then logically the HEAD reflog should be
1390 * updated too.
1391 * A generic solution implies reverse symref information,
1392 * but finding all symrefs pointing to the given branch
1393 * would be rather costly for this rare event (the direct
1394 * update of a branch) to be worth it. So let's cheat and
1395 * check with HEAD only which should cover 99% of all usage
1396 * scenarios (even 100% of the default ones).
1397 */
1398 unsigned char head_sha1[20];
1399 int head_flag;
1400 const char *head_ref;
1401 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1402 if (head_ref && (head_flag & REF_ISSYMREF) &&
1403 !strcmp(head_ref, lock->ref_name))
1404 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1405 }
b531394d 1406 if (commit_ref(lock)) {
434cd0cd 1407 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1408 unlock_ref(lock);
1409 return -1;
1410 }
4bd18c43
SP
1411 unlock_ref(lock);
1412 return 0;
95fc7512 1413}
d556fae2 1414
8b5157e4
NP
1415int create_symref(const char *ref_target, const char *refs_heads_master,
1416 const char *logmsg)
41b625b0
NP
1417{
1418 const char *lockpath;
1419 char ref[1000];
1420 int fd, len, written;
a4f34cbb 1421 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1422 unsigned char old_sha1[20], new_sha1[20];
1423
1424 if (logmsg && read_ref(ref_target, old_sha1))
1425 hashclr(old_sha1);
41b625b0 1426
d48744d1
JH
1427 if (safe_create_leading_directories(git_HEAD) < 0)
1428 return error("unable to create directory for %s", git_HEAD);
1429
41b625b0
NP
1430#ifndef NO_SYMLINK_HEAD
1431 if (prefer_symlink_refs) {
1432 unlink(git_HEAD);
1433 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1434 goto done;
41b625b0
NP
1435 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1436 }
1437#endif
1438
1439 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1440 if (sizeof(ref) <= len) {
1441 error("refname too long: %s", refs_heads_master);
47fc52e2 1442 goto error_free_return;
41b625b0
NP
1443 }
1444 lockpath = mkpath("%s.lock", git_HEAD);
1445 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1446 if (fd < 0) {
1447 error("Unable to open %s for writing", lockpath);
47fc52e2 1448 goto error_free_return;
41b625b0
NP
1449 }
1450 written = write_in_full(fd, ref, len);
91c8d590 1451 if (close(fd) != 0 || written != len) {
41b625b0 1452 error("Unable to write to %s", lockpath);
47fc52e2 1453 goto error_unlink_return;
41b625b0
NP
1454 }
1455 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1456 error("Unable to create %s", git_HEAD);
47fc52e2 1457 goto error_unlink_return;
41b625b0
NP
1458 }
1459 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1460 error("Unable to fix permissions on %s", lockpath);
47fc52e2 1461 error_unlink_return:
691f1a28 1462 unlink_or_warn(lockpath);
47fc52e2
JH
1463 error_free_return:
1464 free(git_HEAD);
1465 return -1;
41b625b0 1466 }
8b5157e4 1467
ee96d11b 1468#ifndef NO_SYMLINK_HEAD
8b5157e4 1469 done:
ee96d11b 1470#endif
8b5157e4
NP
1471 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1472 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1473
47fc52e2 1474 free(git_HEAD);
41b625b0
NP
1475 return 0;
1476}
1477
16d7cc90
JH
1478static char *ref_msg(const char *line, const char *endp)
1479{
1480 const char *ep;
16d7cc90 1481 line += 82;
182af834
PH
1482 ep = memchr(line, '\n', endp - line);
1483 if (!ep)
1484 ep = endp;
1485 return xmemdupz(line, ep - line);
16d7cc90
JH
1486}
1487
1488int 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)
d556fae2 1489{
e5229042 1490 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1491 char *tz_c;
e29cb53a 1492 int logfd, tz, reccnt = 0;
d556fae2
SP
1493 struct stat st;
1494 unsigned long date;
e5229042 1495 unsigned char logged_sha1[20];
cb48cb58 1496 void *log_mapped;
dc49cd76 1497 size_t mapsz;
d556fae2
SP
1498
1499 logfile = git_path("logs/%s", ref);
1500 logfd = open(logfile, O_RDONLY, 0);
1501 if (logfd < 0)
d824cbba 1502 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
1503 fstat(logfd, &st);
1504 if (!st.st_size)
1505 die("Log %s is empty.", logfile);
dc49cd76
SP
1506 mapsz = xsize_t(st.st_size);
1507 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1508 logdata = log_mapped;
d556fae2
SP
1509 close(logfd);
1510
e5229042 1511 lastrec = NULL;
d556fae2
SP
1512 rec = logend = logdata + st.st_size;
1513 while (logdata < rec) {
e29cb53a 1514 reccnt++;
d556fae2
SP
1515 if (logdata < rec && *(rec-1) == '\n')
1516 rec--;
e5229042
SP
1517 lastgt = NULL;
1518 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1519 rec--;
e5229042
SP
1520 if (*rec == '>')
1521 lastgt = rec;
1522 }
1523 if (!lastgt)
d556fae2 1524 die("Log %s is corrupt.", logfile);
e5229042 1525 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1526 if (date <= at_time || cnt == 0) {
76a44c5c 1527 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1528 if (msg)
1529 *msg = ref_msg(rec, logend);
1530 if (cutoff_time)
1531 *cutoff_time = date;
1532 if (cutoff_tz)
1533 *cutoff_tz = tz;
1534 if (cutoff_cnt)
76a44c5c 1535 *cutoff_cnt = reccnt - 1;
e5229042
SP
1536 if (lastrec) {
1537 if (get_sha1_hex(lastrec, logged_sha1))
1538 die("Log %s is corrupt.", logfile);
1539 if (get_sha1_hex(rec + 41, sha1))
1540 die("Log %s is corrupt.", logfile);
a89fccd2 1541 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1542 warning("Log %s has gap after %s.",
73013afd 1543 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1544 }
e5f38ec3
JH
1545 }
1546 else if (date == at_time) {
e5229042
SP
1547 if (get_sha1_hex(rec + 41, sha1))
1548 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1549 }
1550 else {
e5229042
SP
1551 if (get_sha1_hex(rec + 41, logged_sha1))
1552 die("Log %s is corrupt.", logfile);
a89fccd2 1553 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1554 warning("Log %s unexpectedly ended on %s.",
73013afd 1555 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1556 }
1557 }
dc49cd76 1558 munmap(log_mapped, mapsz);
d556fae2
SP
1559 return 0;
1560 }
e5229042 1561 lastrec = rec;
ab2a1a32
JH
1562 if (cnt > 0)
1563 cnt--;
d556fae2
SP
1564 }
1565
e5229042
SP
1566 rec = logdata;
1567 while (rec < logend && *rec != '>' && *rec != '\n')
1568 rec++;
1569 if (rec == logend || *rec == '\n')
d556fae2 1570 die("Log %s is corrupt.", logfile);
e5229042 1571 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1572 tz = strtoul(tz_c, NULL, 10);
1573 if (get_sha1_hex(logdata, sha1))
1574 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1575 if (is_null_sha1(sha1)) {
1576 if (get_sha1_hex(logdata + 41, sha1))
1577 die("Log %s is corrupt.", logfile);
1578 }
16d7cc90
JH
1579 if (msg)
1580 *msg = ref_msg(logdata, logend);
dc49cd76 1581 munmap(log_mapped, mapsz);
16d7cc90
JH
1582
1583 if (cutoff_time)
1584 *cutoff_time = date;
1585 if (cutoff_tz)
1586 *cutoff_tz = tz;
1587 if (cutoff_cnt)
1588 *cutoff_cnt = reccnt;
1589 return 1;
d556fae2 1590}
2ff81662 1591
101d15e0 1592int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
1593{
1594 const char *logfile;
1595 FILE *logfp;
8ca78803 1596 struct strbuf sb = STRBUF_INIT;
2266bf27 1597 int ret = 0;
2ff81662
JH
1598
1599 logfile = git_path("logs/%s", ref);
1600 logfp = fopen(logfile, "r");
1601 if (!logfp)
883d60fa 1602 return -1;
101d15e0
JH
1603
1604 if (ofs) {
1605 struct stat statbuf;
1606 if (fstat(fileno(logfp), &statbuf) ||
1607 statbuf.st_size < ofs ||
1608 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 1609 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 1610 fclose(logfp);
8ca78803 1611 strbuf_release(&sb);
101d15e0 1612 return -1;
9d33f7c2 1613 }
101d15e0
JH
1614 }
1615
8ca78803 1616 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 1617 unsigned char osha1[20], nsha1[20];
883d60fa
JS
1618 char *email_end, *message;
1619 unsigned long timestamp;
8ca78803 1620 int tz;
2ff81662
JH
1621
1622 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
1623 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1624 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1625 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1626 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
1627 email_end[1] != ' ' ||
1628 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1629 !message || message[0] != ' ' ||
1630 (message[1] != '+' && message[1] != '-') ||
1631 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 1632 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 1633 continue; /* corrupt? */
883d60fa
JS
1634 email_end[1] = '\0';
1635 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
1636 if (message[6] != '\t')
1637 message += 6;
1638 else
1639 message += 7;
8ca78803
RS
1640 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1641 cb_data);
883d60fa 1642 if (ret)
2266bf27 1643 break;
2ff81662
JH
1644 }
1645 fclose(logfp);
8ca78803 1646 strbuf_release(&sb);
2266bf27 1647 return ret;
2ff81662 1648}
e29cb53a 1649
101d15e0
JH
1650int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1651{
1652 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1653}
1654
eb8381c8
NP
1655static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1656{
1657 DIR *dir = opendir(git_path("logs/%s", base));
fcee5a14 1658 int retval = 0;
eb8381c8
NP
1659
1660 if (dir) {
1661 struct dirent *de;
1662 int baselen = strlen(base);
1663 char *log = xmalloc(baselen + 257);
1664
1665 memcpy(log, base, baselen);
1666 if (baselen && base[baselen-1] != '/')
1667 log[baselen++] = '/';
1668
1669 while ((de = readdir(dir)) != NULL) {
1670 struct stat st;
1671 int namelen;
1672
1673 if (de->d_name[0] == '.')
1674 continue;
1675 namelen = strlen(de->d_name);
1676 if (namelen > 255)
1677 continue;
1678 if (has_extension(de->d_name, ".lock"))
1679 continue;
1680 memcpy(log + baselen, de->d_name, namelen+1);
1681 if (stat(git_path("logs/%s", log), &st) < 0)
1682 continue;
1683 if (S_ISDIR(st.st_mode)) {
1684 retval = do_for_each_reflog(log, fn, cb_data);
1685 } else {
1686 unsigned char sha1[20];
1687 if (!resolve_ref(log, sha1, 0, NULL))
1688 retval = error("bad ref for %s", log);
1689 else
1690 retval = fn(log, sha1, 0, cb_data);
1691 }
1692 if (retval)
1693 break;
1694 }
1695 free(log);
1696 closedir(dir);
1697 }
acb39f64 1698 else if (*base)
fcee5a14 1699 return errno;
eb8381c8
NP
1700 return retval;
1701}
1702
1703int for_each_reflog(each_ref_fn fn, void *cb_data)
1704{
1705 return do_for_each_reflog("", fn, cb_data);
1706}
3d9f037c
CR
1707
1708int update_ref(const char *action, const char *refname,
1709 const unsigned char *sha1, const unsigned char *oldval,
1710 int flags, enum action_on_err onerr)
1711{
1712 static struct ref_lock *lock;
1713 lock = lock_any_ref_for_update(refname, oldval, flags);
1714 if (!lock) {
1715 const char *str = "Cannot lock the ref '%s'.";
1716 switch (onerr) {
1717 case MSG_ON_ERR: error(str, refname); break;
1718 case DIE_ON_ERR: die(str, refname); break;
1719 case QUIET_ON_ERR: break;
1720 }
1721 return 1;
1722 }
1723 if (write_ref_sha1(lock, sha1, action) < 0) {
1724 const char *str = "Cannot update the ref '%s'.";
1725 switch (onerr) {
1726 case MSG_ON_ERR: error(str, refname); break;
1727 case DIE_ON_ERR: die(str, refname); break;
1728 case QUIET_ON_ERR: break;
1729 }
1730 return 1;
1731 }
1732 return 0;
1733}
cda69f48 1734
5483f799 1735struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
1736{
1737 for ( ; list; list = list->next)
1738 if (!strcmp(list->name, name))
5483f799 1739 return (struct ref *)list;
cda69f48
JK
1740 return NULL;
1741}
7c2b3029
JK
1742
1743/*
1744 * generate a format suitable for scanf from a ref_rev_parse_rules
1745 * rule, that is replace the "%.*s" spec with a "%s" spec
1746 */
1747static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1748{
1749 char *spec;
1750
1751 spec = strstr(rule, "%.*s");
1752 if (!spec || strstr(spec + 4, "%.*s"))
1753 die("invalid rule in ref_rev_parse_rules: %s", rule);
1754
1755 /* copy all until spec */
1756 strncpy(scanf_fmt, rule, spec - rule);
1757 scanf_fmt[spec - rule] = '\0';
1758 /* copy new spec */
1759 strcat(scanf_fmt, "%s");
1760 /* copy remaining rule */
1761 strcat(scanf_fmt, spec + 4);
1762
1763 return;
1764}
1765
6e7b3309 1766char *shorten_unambiguous_ref(const char *ref, int strict)
7c2b3029
JK
1767{
1768 int i;
1769 static char **scanf_fmts;
1770 static int nr_rules;
1771 char *short_name;
1772
1773 /* pre generate scanf formats from ref_rev_parse_rules[] */
1774 if (!nr_rules) {
1775 size_t total_len = 0;
1776
1777 /* the rule list is NULL terminated, count them first */
1778 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1779 /* no +1 because strlen("%s") < strlen("%.*s") */
1780 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1781
1782 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1783
1784 total_len = 0;
1785 for (i = 0; i < nr_rules; i++) {
1786 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1787 + total_len;
1788 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1789 total_len += strlen(ref_rev_parse_rules[i]);
1790 }
1791 }
1792
1793 /* bail out if there are no rules */
1794 if (!nr_rules)
1795 return xstrdup(ref);
1796
1797 /* buffer for scanf result, at most ref must fit */
1798 short_name = xstrdup(ref);
1799
1800 /* skip first rule, it will always match */
1801 for (i = nr_rules - 1; i > 0 ; --i) {
1802 int j;
6e7b3309 1803 int rules_to_fail = i;
7c2b3029
JK
1804 int short_name_len;
1805
1806 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1807 continue;
1808
1809 short_name_len = strlen(short_name);
1810
6e7b3309
BW
1811 /*
1812 * in strict mode, all (except the matched one) rules
1813 * must fail to resolve to a valid non-ambiguous ref
1814 */
1815 if (strict)
1816 rules_to_fail = nr_rules;
1817
7c2b3029
JK
1818 /*
1819 * check if the short name resolves to a valid ref,
1820 * but use only rules prior to the matched one
1821 */
6e7b3309 1822 for (j = 0; j < rules_to_fail; j++) {
7c2b3029
JK
1823 const char *rule = ref_rev_parse_rules[j];
1824 unsigned char short_objectname[20];
1825 char refname[PATH_MAX];
1826
6e7b3309
BW
1827 /* skip matched rule */
1828 if (i == j)
1829 continue;
1830
7c2b3029
JK
1831 /*
1832 * the short name is ambiguous, if it resolves
1833 * (with this previous rule) to a valid ref
1834 * read_ref() returns 0 on success
1835 */
1836 mksnpath(refname, sizeof(refname),
1837 rule, short_name_len, short_name);
1838 if (!read_ref(refname, short_objectname))
1839 break;
1840 }
1841
1842 /*
1843 * short name is non-ambiguous if all previous rules
1844 * haven't resolved to a valid ref
1845 */
6e7b3309 1846 if (j == rules_to_fail)
7c2b3029
JK
1847 return short_name;
1848 }
1849
1850 free(short_name);
1851 return xstrdup(ref);
1852}