Store the submodule name in struct cached_refs
[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;
ce40979c
MH
160 /* The submodule name, or "" for the main repo. */
161 char name[FLEX_ARRAY];
e5dbf605 162} *cached_refs, *submodule_refs;
0ae91be0 163static struct ref_list *current_ref;
5e290ff7 164
e142a3c6
DB
165static struct ref_list *extra_refs;
166
5e290ff7
JH
167static void free_ref_list(struct ref_list *list)
168{
169 struct ref_list *next;
170 for ( ; list; list = next) {
171 next = list->next;
172 free(list);
173 }
174}
175
f130b116 176static void clear_cached_refs(struct cached_refs *ca)
e1e22e37 177{
5e290ff7
JH
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;
f130b116
MH
184}
185
ce40979c 186struct cached_refs *create_cached_refs(const char *submodule)
e5dbf605 187{
ce40979c 188 int len;
e5dbf605 189 struct cached_refs *refs;
ce40979c
MH
190 if (!submodule)
191 submodule = "";
192 len = strlen(submodule) + 1;
193 refs = xmalloc(sizeof(struct cached_refs) + len);
e5dbf605
MH
194 refs->did_loose = refs->did_packed = 0;
195 refs->loose = refs->packed = NULL;
ce40979c 196 memcpy(refs->name, submodule, len);
e5dbf605
MH
197 return refs;
198}
199
4349a668
MH
200/*
201 * Return a pointer to a cached_refs for the specified submodule. For
202 * the main repository, use submodule==NULL. The returned structure
203 * will be allocated and initialized but not necessarily populated; it
204 * should not be freed.
205 */
206static struct cached_refs *get_cached_refs(const char *submodule)
207{
e5dbf605
MH
208 if (!submodule) {
209 if (!cached_refs)
ce40979c 210 cached_refs = create_cached_refs(submodule);
e5dbf605
MH
211 return cached_refs;
212 } else {
213 if (!submodule_refs)
ce40979c 214 submodule_refs = create_cached_refs(submodule);
e5dbf605
MH
215 else
216 /* For now, don't reuse the refs cache for submodules. */
217 clear_cached_refs(submodule_refs);
218 return submodule_refs;
4349a668
MH
219 }
220}
221
f130b116
MH
222static void invalidate_cached_refs(void)
223{
4349a668 224 clear_cached_refs(get_cached_refs(NULL));
5e290ff7 225}
e1e22e37 226
db4dd93a 227static struct ref_list *read_packed_refs(FILE *f)
f4204ab9
JH
228{
229 struct ref_list *list = NULL;
230 struct ref_list *last = NULL;
231 char refline[PATH_MAX];
232 int flag = REF_ISPACKED;
233
234 while (fgets(refline, sizeof(refline), f)) {
235 unsigned char sha1[20];
236 const char *name;
237 static const char header[] = "# pack-refs with:";
238
239 if (!strncmp(refline, header, sizeof(header)-1)) {
240 const char *traits = refline + sizeof(header) - 1;
241 if (strstr(traits, " peeled "))
242 flag |= REF_KNOWS_PEELED;
243 /* perhaps other traits later as well */
244 continue;
245 }
246
247 name = parse_ref_line(refline, sha1);
248 if (name) {
249 list = add_ref(name, sha1, flag, list, &last);
250 continue;
251 }
252 if (last &&
253 refline[0] == '^' &&
254 strlen(refline) == 42 &&
255 refline[41] == '\n' &&
256 !get_sha1_hex(refline + 1, sha1))
257 hashcpy(last->peeled, sha1);
258 }
db4dd93a 259 return sort_ref_list(list);
f4204ab9
JH
260}
261
e142a3c6
DB
262void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
263{
264 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
265}
266
267void clear_extra_refs(void)
268{
269 free_ref_list(extra_refs);
270 extra_refs = NULL;
271}
272
0bad611b 273static struct ref_list *get_packed_refs(const char *submodule)
5e290ff7 274{
4349a668 275 struct cached_refs *refs = get_cached_refs(submodule);
0bad611b 276
4349a668
MH
277 if (!refs->did_packed) {
278 const char *packed_refs_file;
279 FILE *f;
280
281 if (submodule)
282 packed_refs_file = git_path_submodule(submodule, "packed-refs");
283 else
284 packed_refs_file = git_path("packed-refs");
285 f = fopen(packed_refs_file, "r");
0bad611b 286 refs->packed = NULL;
e1e22e37 287 if (f) {
db4dd93a 288 refs->packed = read_packed_refs(f);
e1e22e37 289 fclose(f);
e1e22e37 290 }
0bad611b 291 refs->did_packed = 1;
e1e22e37 292 }
0bad611b 293 return refs->packed;
e1e22e37
LT
294}
295
0bad611b
HV
296static struct ref_list *get_ref_dir(const char *submodule, const char *base,
297 struct ref_list *list)
e1e22e37 298{
0bad611b
HV
299 DIR *dir;
300 const char *path;
301
302 if (submodule)
303 path = git_path_submodule(submodule, "%s", base);
304 else
305 path = git_path("%s", base);
306
307
308 dir = opendir(path);
e1e22e37
LT
309
310 if (dir) {
311 struct dirent *de;
312 int baselen = strlen(base);
ed378ec7 313 char *ref = xmalloc(baselen + 257);
e1e22e37 314
ed378ec7 315 memcpy(ref, base, baselen);
e1e22e37 316 if (baselen && base[baselen-1] != '/')
ed378ec7 317 ref[baselen++] = '/';
e1e22e37
LT
318
319 while ((de = readdir(dir)) != NULL) {
320 unsigned char sha1[20];
321 struct stat st;
8da19775 322 int flag;
e1e22e37 323 int namelen;
0bad611b 324 const char *refdir;
e1e22e37
LT
325
326 if (de->d_name[0] == '.')
327 continue;
328 namelen = strlen(de->d_name);
329 if (namelen > 255)
330 continue;
331 if (has_extension(de->d_name, ".lock"))
332 continue;
ed378ec7 333 memcpy(ref + baselen, de->d_name, namelen+1);
0bad611b
HV
334 refdir = submodule
335 ? git_path_submodule(submodule, "%s", ref)
336 : git_path("%s", ref);
337 if (stat(refdir, &st) < 0)
e1e22e37
LT
338 continue;
339 if (S_ISDIR(st.st_mode)) {
0bad611b 340 list = get_ref_dir(submodule, ref, list);
e1e22e37
LT
341 continue;
342 }
0bad611b 343 if (submodule) {
f8948e2f 344 hashclr(sha1);
0bad611b
HV
345 flag = 0;
346 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
347 hashclr(sha1);
348 flag |= REF_BROKEN;
349 }
350 } else
351 if (!resolve_ref(ref, sha1, 1, &flag)) {
352 hashclr(sha1);
353 flag |= REF_BROKEN;
354 }
f4204ab9 355 list = add_ref(ref, sha1, flag, list, NULL);
e1e22e37 356 }
ed378ec7 357 free(ref);
e1e22e37
LT
358 closedir(dir);
359 }
c774aab9 360 return sort_ref_list(list);
e1e22e37
LT
361}
362
f8948e2f 363struct warn_if_dangling_data {
3cf6134a 364 FILE *fp;
f8948e2f
JH
365 const char *refname;
366 const char *msg_fmt;
367};
368
369static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
370 int flags, void *cb_data)
371{
372 struct warn_if_dangling_data *d = cb_data;
373 const char *resolves_to;
374 unsigned char junk[20];
375
376 if (!(flags & REF_ISSYMREF))
377 return 0;
378
379 resolves_to = resolve_ref(refname, junk, 0, NULL);
380 if (!resolves_to || strcmp(resolves_to, d->refname))
381 return 0;
382
3cf6134a 383 fprintf(d->fp, d->msg_fmt, refname);
f8948e2f
JH
384 return 0;
385}
386
3cf6134a 387void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
f8948e2f 388{
66dbfd55
GV
389 struct warn_if_dangling_data data;
390
391 data.fp = fp;
392 data.refname = refname;
393 data.msg_fmt = msg_fmt;
f8948e2f
JH
394 for_each_rawref(warn_if_dangling_symref, &data);
395}
396
0bad611b 397static struct ref_list *get_loose_refs(const char *submodule)
e1e22e37 398{
4349a668 399 struct cached_refs *refs = get_cached_refs(submodule);
0bad611b 400
4349a668
MH
401 if (!refs->did_loose) {
402 refs->loose = get_ref_dir(submodule, "refs", NULL);
403 refs->did_loose = 1;
e1e22e37 404 }
4349a668 405 return refs->loose;
e1e22e37
LT
406}
407
ca8db142
LT
408/* We allow "recursive" symbolic refs. Only within reason, though */
409#define MAXDEPTH 5
0ebde32c
LT
410#define MAXREFLEN (1024)
411
412static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
413{
414 FILE *f;
db4dd93a 415 struct ref_list *packed_refs;
0ebde32c
LT
416 struct ref_list *ref;
417 int retval;
418
419 strcpy(name + pathlen, "packed-refs");
420 f = fopen(name, "r");
421 if (!f)
422 return -1;
db4dd93a 423 packed_refs = read_packed_refs(f);
0ebde32c 424 fclose(f);
db4dd93a 425 ref = packed_refs;
0ebde32c
LT
426 retval = -1;
427 while (ref) {
428 if (!strcmp(ref->name, refname)) {
429 retval = 0;
430 memcpy(result, ref->sha1, 20);
431 break;
432 }
433 ref = ref->next;
434 }
db4dd93a 435 free_ref_list(packed_refs);
0ebde32c
LT
436 return retval;
437}
438
439static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
440{
441 int fd, len = strlen(refname);
442 char buffer[128], *p;
443
444 if (recursion > MAXDEPTH || len > MAXREFLEN)
445 return -1;
446 memcpy(name + pathlen, refname, len+1);
447 fd = open(name, O_RDONLY);
448 if (fd < 0)
449 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
450
451 len = read(fd, buffer, sizeof(buffer)-1);
452 close(fd);
453 if (len < 0)
454 return -1;
455 while (len && isspace(buffer[len-1]))
456 len--;
457 buffer[len] = 0;
458
459 /* Was it a detached head or an old-fashioned symlink? */
460 if (!get_sha1_hex(buffer, result))
461 return 0;
462
463 /* Symref? */
464 if (strncmp(buffer, "ref:", 4))
465 return -1;
466 p = buffer + 4;
467 while (isspace(*p))
468 p++;
469
470 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
471}
472
473int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
474{
475 int len = strlen(path), retval;
476 char *gitdir;
842abf06 477 const char *tmp;
0ebde32c
LT
478
479 while (len && path[len-1] == '/')
480 len--;
481 if (!len)
482 return -1;
483 gitdir = xmalloc(len + MAXREFLEN + 8);
484 memcpy(gitdir, path, len);
842abf06
LH
485 memcpy(gitdir + len, "/.git", 6);
486 len += 5;
487
488 tmp = read_gitfile_gently(gitdir);
489 if (tmp) {
490 free(gitdir);
491 len = strlen(tmp);
492 gitdir = xmalloc(len + MAXREFLEN + 3);
493 memcpy(gitdir, tmp, len);
494 }
495 gitdir[len] = '/';
496 gitdir[++len] = '\0';
497 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
0ebde32c
LT
498 free(gitdir);
499 return retval;
500}
ca8db142 501
4886b89f
CC
502/*
503 * If the "reading" argument is set, this function finds out what _object_
504 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
505 * has to exist, and if it is symbolic, it has to point at an existing ref,
506 * because the "read" goes through the symref to the ref it points at.
507 *
508 * The access that is not "reading" may often be "writing", but does not
509 * have to; it can be merely checking _where it leads to_. If it is a
510 * prelude to "writing" to the ref, a write to a symref that points at
511 * yet-to-be-born ref will create the real ref pointed by the symref.
512 * reading=0 allows the caller to check where such a symref leads to.
513 */
8da19775 514const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
8a65ff76 515{
0104ca09
HO
516 int depth = MAXDEPTH;
517 ssize_t len;
a876ed83 518 char buffer[256];
ed378ec7 519 static char ref_buffer[256];
ca8db142 520
8da19775
JH
521 if (flag)
522 *flag = 0;
523
a876ed83 524 for (;;) {
958a4789 525 char path[PATH_MAX];
a876ed83
JH
526 struct stat st;
527 char *buf;
528 int fd;
8a65ff76 529
a876ed83
JH
530 if (--depth < 0)
531 return NULL;
ca8db142 532
958a4789 533 git_snpath(path, sizeof(path), "%s", ref);
4886b89f 534 /* Special case: non-existing file. */
a876ed83 535 if (lstat(path, &st) < 0) {
0bad611b 536 struct ref_list *list = get_packed_refs(NULL);
434cd0cd 537 while (list) {
f4204ab9 538 if (!strcmp(ref, list->name)) {
434cd0cd 539 hashcpy(sha1, list->sha1);
8da19775
JH
540 if (flag)
541 *flag |= REF_ISPACKED;
434cd0cd
LT
542 return ref;
543 }
544 list = list->next;
545 }
a876ed83
JH
546 if (reading || errno != ENOENT)
547 return NULL;
e702496e 548 hashclr(sha1);
ed378ec7 549 return ref;
a876ed83 550 }
ca8db142 551
a876ed83
JH
552 /* Follow "normalized" - ie "refs/.." symlinks by hand */
553 if (S_ISLNK(st.st_mode)) {
554 len = readlink(path, buffer, sizeof(buffer)-1);
555 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
ed378ec7
LT
556 buffer[len] = 0;
557 strcpy(ref_buffer, buffer);
558 ref = ref_buffer;
8da19775
JH
559 if (flag)
560 *flag |= REF_ISSYMREF;
a876ed83
JH
561 continue;
562 }
ca8db142 563 }
a876ed83 564
7a21632f
DS
565 /* Is it a directory? */
566 if (S_ISDIR(st.st_mode)) {
567 errno = EISDIR;
568 return NULL;
569 }
570
a876ed83
JH
571 /*
572 * Anything else, just open it and try to use it as
573 * a ref
574 */
575 fd = open(path, O_RDONLY);
576 if (fd < 0)
577 return NULL;
93d26e4c 578 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83
JH
579 close(fd);
580
581 /*
582 * Is it a symbolic ref?
583 */
584 if (len < 4 || memcmp("ref:", buffer, 4))
585 break;
586 buf = buffer + 4;
587 len -= 4;
588 while (len && isspace(*buf))
589 buf++, len--;
590 while (len && isspace(buf[len-1]))
ed378ec7
LT
591 len--;
592 buf[len] = 0;
593 memcpy(ref_buffer, buf, len + 1);
594 ref = ref_buffer;
8da19775
JH
595 if (flag)
596 *flag |= REF_ISSYMREF;
8a65ff76 597 }
a876ed83
JH
598 if (len < 40 || get_sha1_hex(buffer, sha1))
599 return NULL;
ed378ec7 600 return ref;
a876ed83
JH
601}
602
d08bae7e
IL
603/* The argument to filter_refs */
604struct ref_filter {
605 const char *pattern;
606 each_ref_fn *fn;
607 void *cb_data;
608};
609
ed378ec7 610int read_ref(const char *ref, unsigned char *sha1)
a876ed83 611{
8da19775 612 if (resolve_ref(ref, sha1, 1, NULL))
a876ed83
JH
613 return 0;
614 return -1;
8a65ff76
LT
615}
616
f8948e2f 617#define DO_FOR_EACH_INCLUDE_BROKEN 01
ef06b918 618static int do_one_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 619 int flags, void *cb_data, struct ref_list *entry)
ef06b918
JH
620{
621 if (strncmp(base, entry->name, trim))
622 return 0;
e01de1c9 623
f8948e2f 624 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
e01de1c9
JH
625 if (entry->flag & REF_BROKEN)
626 return 0; /* ignore dangling symref */
f8948e2f
JH
627 if (!has_sha1_file(entry->sha1)) {
628 error("%s does not point to a valid object!", entry->name);
629 return 0;
630 }
ef06b918 631 }
0ae91be0 632 current_ref = entry;
ef06b918
JH
633 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
634}
635
d08bae7e
IL
636static int filter_refs(const char *ref, const unsigned char *sha, int flags,
637 void *data)
638{
639 struct ref_filter *filter = (struct ref_filter *)data;
640 if (fnmatch(filter->pattern, ref, 0))
641 return 0;
642 return filter->fn(ref, sha, flags, filter->cb_data);
643}
644
cf0adba7
JH
645int peel_ref(const char *ref, unsigned char *sha1)
646{
647 int flag;
648 unsigned char base[20];
649 struct object *o;
650
0ae91be0
SP
651 if (current_ref && (current_ref->name == ref
652 || !strcmp(current_ref->name, ref))) {
653 if (current_ref->flag & REF_KNOWS_PEELED) {
654 hashcpy(sha1, current_ref->peeled);
655 return 0;
656 }
657 hashcpy(base, current_ref->sha1);
658 goto fallback;
659 }
660
cf0adba7
JH
661 if (!resolve_ref(ref, base, 1, &flag))
662 return -1;
663
664 if ((flag & REF_ISPACKED)) {
0bad611b 665 struct ref_list *list = get_packed_refs(NULL);
cf0adba7
JH
666
667 while (list) {
f4204ab9
JH
668 if (!strcmp(list->name, ref)) {
669 if (list->flag & REF_KNOWS_PEELED) {
670 hashcpy(sha1, list->peeled);
671 return 0;
672 }
673 /* older pack-refs did not leave peeled ones */
674 break;
cf0adba7
JH
675 }
676 list = list->next;
677 }
cf0adba7
JH
678 }
679
0ae91be0 680fallback:
cf0adba7 681 o = parse_object(base);
8c87dc77 682 if (o && o->type == OBJ_TAG) {
cf0adba7
JH
683 o = deref_tag(o, ref, 0);
684 if (o) {
685 hashcpy(sha1, o->sha1);
686 return 0;
687 }
688 }
689 return -1;
690}
691
0bad611b
HV
692static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
693 int trim, int flags, void *cb_data)
8a65ff76 694{
0ae91be0 695 int retval = 0;
0bad611b
HV
696 struct ref_list *packed = get_packed_refs(submodule);
697 struct ref_list *loose = get_loose_refs(submodule);
8a65ff76 698
e142a3c6
DB
699 struct ref_list *extra;
700
701 for (extra = extra_refs; extra; extra = extra->next)
f8948e2f 702 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
e142a3c6 703
e1e22e37
LT
704 while (packed && loose) {
705 struct ref_list *entry;
706 int cmp = strcmp(packed->name, loose->name);
707 if (!cmp) {
708 packed = packed->next;
709 continue;
6cada6a9 710 }
e1e22e37
LT
711 if (cmp > 0) {
712 entry = loose;
713 loose = loose->next;
714 } else {
715 entry = packed;
716 packed = packed->next;
717 }
f8948e2f 718 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
e1e22e37 719 if (retval)
0ae91be0 720 goto end_each;
e1e22e37 721 }
8a65ff76 722
ef06b918 723 for (packed = packed ? packed : loose; packed; packed = packed->next) {
f8948e2f 724 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
ef06b918 725 if (retval)
0ae91be0 726 goto end_each;
8a65ff76 727 }
0ae91be0
SP
728
729end_each:
730 current_ref = NULL;
731 return retval;
8a65ff76
LT
732}
733
0bad611b
HV
734
735static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
736{
737 unsigned char sha1[20];
8da19775
JH
738 int flag;
739
0bad611b
HV
740 if (submodule) {
741 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
742 return fn("HEAD", sha1, 0, cb_data);
743
744 return 0;
745 }
746
8da19775
JH
747 if (resolve_ref("HEAD", sha1, 1, &flag))
748 return fn("HEAD", sha1, flag, cb_data);
0bad611b 749
2f34ba32 750 return 0;
723c31fe
LT
751}
752
0bad611b
HV
753int head_ref(each_ref_fn fn, void *cb_data)
754{
755 return do_head_ref(NULL, fn, cb_data);
756}
757
9ef6aeb0
HV
758int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
759{
760 return do_head_ref(submodule, fn, cb_data);
761}
762
cb5d709f 763int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 764{
0bad611b 765 return do_for_each_ref(NULL, "refs/", fn, 0, 0, cb_data);
a62be77f
SE
766}
767
9ef6aeb0
HV
768int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
769{
770 return do_for_each_ref(submodule, "refs/", fn, 0, 0, cb_data);
a62be77f
SE
771}
772
2a8177b6
CC
773int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
774{
0bad611b 775 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
776}
777
9ef6aeb0
HV
778int for_each_ref_in_submodule(const char *submodule, const char *prefix,
779 each_ref_fn fn, void *cb_data)
780{
781 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
782}
783
cb5d709f 784int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 785{
2a8177b6 786 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
787}
788
9ef6aeb0
HV
789int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
790{
791 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
792}
793
cb5d709f 794int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 795{
2a8177b6 796 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
797}
798
9ef6aeb0
HV
799int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
800{
801 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
802}
803
cb5d709f 804int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 805{
2a8177b6 806 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
807}
808
9ef6aeb0
HV
809int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
810{
811 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
812}
813
29268700
CC
814int for_each_replace_ref(each_ref_fn fn, void *cb_data)
815{
0bad611b 816 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
817}
818
b09fe971
IL
819int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
820 const char *prefix, void *cb_data)
d08bae7e
IL
821{
822 struct strbuf real_pattern = STRBUF_INIT;
823 struct ref_filter filter;
d08bae7e
IL
824 int ret;
825
b09fe971 826 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 827 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
828 else if (prefix)
829 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
830 strbuf_addstr(&real_pattern, pattern);
831
894a9d33 832 if (!has_glob_specials(pattern)) {
9517e6b8 833 /* Append implied '/' '*' if not present. */
d08bae7e
IL
834 if (real_pattern.buf[real_pattern.len - 1] != '/')
835 strbuf_addch(&real_pattern, '/');
836 /* No need to check for '*', there is none. */
837 strbuf_addch(&real_pattern, '*');
838 }
839
840 filter.pattern = real_pattern.buf;
841 filter.fn = fn;
842 filter.cb_data = cb_data;
843 ret = for_each_ref(filter_refs, &filter);
844
845 strbuf_release(&real_pattern);
846 return ret;
847}
848
b09fe971
IL
849int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
850{
851 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
852}
853
f8948e2f
JH
854int for_each_rawref(each_ref_fn fn, void *cb_data)
855{
0bad611b 856 return do_for_each_ref(NULL, "refs/", fn, 0,
f8948e2f 857 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
858}
859
03feddd6
JH
860/*
861 * Make sure "ref" is something reasonable to have under ".git/refs/";
862 * We do not like it if:
863 *
864 * - any path component of it begins with ".", or
865 * - it has double dots "..", or
866 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
867 * - it ends with a "/".
3e262b95 868 * - it ends with ".lock"
a4c2e699 869 * - it contains a "\" (backslash)
03feddd6
JH
870 */
871
872static inline int bad_ref_char(int ch)
873{
8558fd9e 874 if (((unsigned) ch) <= ' ' ||
a4c2e699 875 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
8558fd9e
DB
876 return 1;
877 /* 2.13 Pattern Matching Notation */
878 if (ch == '?' || ch == '[') /* Unsupported */
879 return 1;
880 if (ch == '*') /* Supported at the end */
881 return 2;
882 return 0;
03feddd6
JH
883}
884
95fc7512
DB
885int check_ref_format(const char *ref)
886{
cbdffe40 887 int ch, level, bad_type, last;
abd2bde7 888 int ret = CHECK_REF_FORMAT_OK;
03feddd6
JH
889 const char *cp = ref;
890
891 level = 0;
892 while (1) {
893 while ((ch = *cp++) == '/')
894 ; /* tolerate duplicated slashes */
895 if (!ch)
5f7b202a
JH
896 /* should not end with slashes */
897 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
898
899 /* we are at the beginning of the path component */
8558fd9e 900 if (ch == '.')
5f7b202a 901 return CHECK_REF_FORMAT_ERROR;
8558fd9e
DB
902 bad_type = bad_ref_char(ch);
903 if (bad_type) {
abd2bde7
DB
904 if (bad_type == 2 && (!*cp || *cp == '/') &&
905 ret == CHECK_REF_FORMAT_OK)
906 ret = CHECK_REF_FORMAT_WILDCARD;
907 else
908 return CHECK_REF_FORMAT_ERROR;
8558fd9e 909 }
03feddd6 910
cbdffe40 911 last = ch;
03feddd6
JH
912 /* scan the rest of the path component */
913 while ((ch = *cp++) != 0) {
8558fd9e 914 bad_type = bad_ref_char(ch);
cbdffe40 915 if (bad_type)
08fbdb30 916 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
917 if (ch == '/')
918 break;
cbdffe40
JH
919 if (last == '.' && ch == '.')
920 return CHECK_REF_FORMAT_ERROR;
921 if (last == '@' && ch == '{')
5f7b202a 922 return CHECK_REF_FORMAT_ERROR;
cbdffe40 923 last = ch;
03feddd6
JH
924 }
925 level++;
926 if (!ch) {
cbdffe40
JH
927 if (ref <= cp - 2 && cp[-2] == '.')
928 return CHECK_REF_FORMAT_ERROR;
03feddd6 929 if (level < 2)
5f7b202a 930 return CHECK_REF_FORMAT_ONELEVEL;
3e262b95
SP
931 if (has_extension(ref, ".lock"))
932 return CHECK_REF_FORMAT_ERROR;
abd2bde7 933 return ret;
03feddd6
JH
934 }
935 }
95fc7512
DB
936}
937
4577e483 938const char *prettify_refname(const char *name)
a9c37a72 939{
a9c37a72
DB
940 return name + (
941 !prefixcmp(name, "refs/heads/") ? 11 :
942 !prefixcmp(name, "refs/tags/") ? 10 :
943 !prefixcmp(name, "refs/remotes/") ? 13 :
944 0);
945}
946
79803322
SP
947const char *ref_rev_parse_rules[] = {
948 "%.*s",
949 "refs/%.*s",
950 "refs/tags/%.*s",
951 "refs/heads/%.*s",
952 "refs/remotes/%.*s",
953 "refs/remotes/%.*s/HEAD",
954 NULL
955};
956
605b4978
SP
957const char *ref_fetch_rules[] = {
958 "%.*s",
959 "refs/%.*s",
960 "refs/heads/%.*s",
961 NULL
962};
963
79803322
SP
964int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
965{
966 const char **p;
967 const int abbrev_name_len = strlen(abbrev_name);
968
969 for (p = rules; *p; p++) {
970 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
971 return 1;
972 }
973 }
974
975 return 0;
976}
977
e5f38ec3 978static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
979 const unsigned char *old_sha1, int mustexist)
980{
8da19775 981 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 982 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
983 unlock_ref(lock);
984 return NULL;
985 }
a89fccd2 986 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 987 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
988 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
989 unlock_ref(lock);
990 return NULL;
991 }
992 return lock;
993}
994
7155b727 995static int remove_empty_directories(const char *file)
bc7127ef
JH
996{
997 /* we want to create a file but there is a directory there;
998 * if that is an empty directory (or a directory that contains
999 * only empty directories), remove them.
1000 */
7155b727
JS
1001 struct strbuf path;
1002 int result;
bc7127ef 1003
7155b727
JS
1004 strbuf_init(&path, 20);
1005 strbuf_addstr(&path, file);
1006
a0f4afbe 1007 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1008
1009 strbuf_release(&path);
1010
1011 return result;
bc7127ef
JH
1012}
1013
c976d415
LH
1014static int is_refname_available(const char *ref, const char *oldref,
1015 struct ref_list *list, int quiet)
1016{
1017 int namlen = strlen(ref); /* e.g. 'foo/bar' */
1018 while (list) {
1019 /* list->name could be 'foo' or 'foo/bar/baz' */
1020 if (!oldref || strcmp(oldref, list->name)) {
1021 int len = strlen(list->name);
1022 int cmplen = (namlen < len) ? namlen : len;
1023 const char *lead = (namlen < len) ? list->name : ref;
1024 if (!strncmp(ref, list->name, cmplen) &&
1025 lead[cmplen] == '/') {
1026 if (!quiet)
1027 error("'%s' exists; cannot create '%s'",
1028 list->name, ref);
1029 return 0;
1030 }
1031 }
1032 list = list->next;
1033 }
1034 return 1;
1035}
1036
68db31cc 1037static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
4bd18c43 1038{
434cd0cd 1039 char *ref_file;
ed378ec7 1040 const char *orig_ref = ref;
4bd18c43 1041 struct ref_lock *lock;
5cc3cef9 1042 int last_errno = 0;
acd3b9ec 1043 int type, lflags;
4431fcc4 1044 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1045 int missing = 0;
4bd18c43
SP
1046
1047 lock = xcalloc(1, sizeof(struct ref_lock));
1048 lock->lock_fd = -1;
1049
68db31cc 1050 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
bc7127ef
JH
1051 if (!ref && errno == EISDIR) {
1052 /* we are trying to lock foo but we used to
1053 * have foo/bar which now does not exist;
1054 * it is normal for the empty directory 'foo'
1055 * to remain.
1056 */
1057 ref_file = git_path("%s", orig_ref);
5cc3cef9
JH
1058 if (remove_empty_directories(ref_file)) {
1059 last_errno = errno;
1060 error("there are still refs under '%s'", orig_ref);
1061 goto error_return;
1062 }
68db31cc 1063 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
bc7127ef 1064 }
68db31cc
SV
1065 if (type_p)
1066 *type_p = type;
ed378ec7 1067 if (!ref) {
5cc3cef9 1068 last_errno = errno;
818f477c 1069 error("unable to resolve reference %s: %s",
ed378ec7 1070 orig_ref, strerror(errno));
5cc3cef9 1071 goto error_return;
4bd18c43 1072 }
5bdd8d4a 1073 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1074 /* When the ref did not exist and we are creating it,
1075 * make sure there is no existing ref that is packed
1076 * whose name begins with our refname, nor a ref whose
1077 * name is a proper prefix of our refname.
1078 */
5bdd8d4a 1079 if (missing &&
0bad611b 1080 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
f475e08e 1081 last_errno = ENOTDIR;
c976d415 1082 goto error_return;
f475e08e 1083 }
22a3844e 1084
c33d5174 1085 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1086
acd3b9ec
JH
1087 lflags = LOCK_DIE_ON_ERROR;
1088 if (flags & REF_NODEREF) {
68db31cc 1089 ref = orig_ref;
acd3b9ec
JH
1090 lflags |= LOCK_NODEREF;
1091 }
434cd0cd 1092 lock->ref_name = xstrdup(ref);
1655707c 1093 lock->orig_ref_name = xstrdup(orig_ref);
7c1a278d 1094 ref_file = git_path("%s", ref);
5bdd8d4a 1095 if (missing)
68db31cc
SV
1096 lock->force_write = 1;
1097 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1098 lock->force_write = 1;
4bd18c43 1099
5cc3cef9
JH
1100 if (safe_create_leading_directories(ref_file)) {
1101 last_errno = errno;
1102 error("unable to create directory for %s", ref_file);
1103 goto error_return;
1104 }
4bd18c43 1105
acd3b9ec 1106 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1107 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1108
1109 error_return:
1110 unlock_ref(lock);
1111 errno = last_errno;
1112 return NULL;
4bd18c43
SP
1113}
1114
4431fcc4 1115struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
95fc7512 1116{
53cce84c 1117 char refpath[PATH_MAX];
95fc7512 1118 if (check_ref_format(ref))
4bd18c43 1119 return NULL;
53cce84c 1120 strcpy(refpath, mkpath("refs/%s", ref));
68db31cc 1121 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1122}
1123
68db31cc 1124struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
4bd18c43 1125{
5f7b202a 1126 switch (check_ref_format(ref)) {
5f7b202a 1127 default:
257f3020
JH
1128 return NULL;
1129 case 0:
1130 case CHECK_REF_FORMAT_ONELEVEL:
5f7b202a
JH
1131 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1132 }
c0277d15
JH
1133}
1134
26a063a1
JH
1135static struct lock_file packlock;
1136
c0277d15
JH
1137static int repack_without_ref(const char *refname)
1138{
1139 struct ref_list *list, *packed_ref_list;
1140 int fd;
1141 int found = 0;
c0277d15 1142
0bad611b 1143 packed_ref_list = get_packed_refs(NULL);
c0277d15
JH
1144 for (list = packed_ref_list; list; list = list->next) {
1145 if (!strcmp(refname, list->name)) {
1146 found = 1;
1147 break;
1148 }
1149 }
1150 if (!found)
1151 return 0;
c0277d15 1152 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1b018fd9
MV
1153 if (fd < 0) {
1154 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1155 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1156 }
c0277d15
JH
1157
1158 for (list = packed_ref_list; list; list = list->next) {
1159 char line[PATH_MAX + 100];
1160 int len;
1161
1162 if (!strcmp(refname, list->name))
1163 continue;
1164 len = snprintf(line, sizeof(line), "%s %s\n",
1165 sha1_to_hex(list->sha1), list->name);
1166 /* this should not happen but just being defensive */
1167 if (len > sizeof(line))
1168 die("too long a refname '%s'", list->name);
1169 write_or_die(fd, line, len);
1170 }
1171 return commit_lock_file(&packlock);
1172}
1173
eca35a25 1174int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1175{
1176 struct ref_lock *lock;
eca35a25 1177 int err, i = 0, ret = 0, flag = 0;
c0277d15 1178
68db31cc 1179 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1180 if (!lock)
1181 return 1;
045a476f 1182 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1183 /* loose */
eca35a25
MV
1184 const char *path;
1185
1186 if (!(delopt & REF_NODEREF)) {
1187 i = strlen(lock->lk->filename) - 5; /* .lock */
1188 lock->lk->filename[i] = 0;
1189 path = lock->lk->filename;
1190 } else {
9db56f71 1191 path = git_path("%s", refname);
eca35a25 1192 }
691f1a28
AR
1193 err = unlink_or_warn(path);
1194 if (err && errno != ENOENT)
c0277d15 1195 ret = 1;
691f1a28 1196
eca35a25
MV
1197 if (!(delopt & REF_NODEREF))
1198 lock->lk->filename[i] = '.';
c0277d15
JH
1199 }
1200 /* removing the loose one could have resurrected an earlier
1201 * packed one. Also, if it was not loose we need to repack
1202 * without it.
1203 */
1204 ret |= repack_without_ref(refname);
1205
691f1a28 1206 unlink_or_warn(git_path("logs/%s", lock->ref_name));
c0277d15
JH
1207 invalidate_cached_refs();
1208 unlock_ref(lock);
1209 return ret;
4bd18c43
SP
1210}
1211
765c2258
PH
1212/*
1213 * People using contrib's git-new-workdir have .git/logs/refs ->
1214 * /some/other/path/.git/logs/refs, and that may live on another device.
1215 *
1216 * IOW, to avoid cross device rename errors, the temporary renamed log must
1217 * live into logs/refs.
1218 */
1219#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1220
678d0f4c 1221int rename_ref(const char *oldref, const char *newref, const char *logmsg)
c976d415
LH
1222{
1223 static const char renamed_ref[] = "RENAMED-REF";
1224 unsigned char sha1[20], orig_sha1[20];
1225 int flag = 0, logmoved = 0;
1226 struct ref_lock *lock;
c976d415 1227 struct stat loginfo;
16c2bfbb 1228 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
eca35a25 1229 const char *symref = NULL;
c976d415 1230
450d4c0f 1231 if (log && S_ISLNK(loginfo.st_mode))
c976d415
LH
1232 return error("reflog for %s is a symlink", oldref);
1233
eca35a25
MV
1234 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1235 if (flag & REF_ISSYMREF)
fa58186c
MV
1236 return error("refname %s is a symbolic ref, renaming it is not supported",
1237 oldref);
eca35a25 1238 if (!symref)
c976d415
LH
1239 return error("refname %s not found", oldref);
1240
0bad611b 1241 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
c976d415
LH
1242 return 1;
1243
0bad611b 1244 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
c976d415
LH
1245 return 1;
1246
68db31cc 1247 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
c976d415
LH
1248 if (!lock)
1249 return error("unable to lock %s", renamed_ref);
1250 lock->force_write = 1;
678d0f4c 1251 if (write_ref_sha1(lock, orig_sha1, logmsg))
c976d415
LH
1252 return error("unable to save current sha1 in %s", renamed_ref);
1253
765c2258
PH
1254 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1255 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
c976d415
LH
1256 oldref, strerror(errno));
1257
eca35a25 1258 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
c976d415
LH
1259 error("unable to delete old %s", oldref);
1260 goto rollback;
1261 }
1262
eca35a25 1263 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
c976d415
LH
1264 if (errno==EISDIR) {
1265 if (remove_empty_directories(git_path("%s", newref))) {
1266 error("Directory not empty: %s", newref);
1267 goto rollback;
1268 }
1269 } else {
1270 error("unable to delete existing %s", newref);
1271 goto rollback;
1272 }
1273 }
1274
1275 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1276 error("unable to create directory for %s", newref);
1277 goto rollback;
1278 }
1279
1280 retry:
765c2258 1281 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
d9e74d57
JR
1282 if (errno==EISDIR || errno==ENOTDIR) {
1283 /*
1284 * rename(a, b) when b is an existing
1285 * directory ought to result in ISDIR, but
1286 * Solaris 5.8 gives ENOTDIR. Sheesh.
1287 */
c976d415
LH
1288 if (remove_empty_directories(git_path("logs/%s", newref))) {
1289 error("Directory not empty: logs/%s", newref);
1290 goto rollback;
1291 }
1292 goto retry;
1293 } else {
765c2258 1294 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
c976d415
LH
1295 newref, strerror(errno));
1296 goto rollback;
1297 }
1298 }
1299 logmoved = log;
1300
68db31cc 1301 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
c976d415
LH
1302 if (!lock) {
1303 error("unable to lock %s for update", newref);
1304 goto rollback;
1305 }
c976d415
LH
1306 lock->force_write = 1;
1307 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1308 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
c976d415
LH
1309 error("unable to write current sha1 into %s", newref);
1310 goto rollback;
1311 }
1312
1313 return 0;
1314
1315 rollback:
68db31cc 1316 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
c976d415
LH
1317 if (!lock) {
1318 error("unable to lock %s for rollback", oldref);
1319 goto rollbacklog;
1320 }
1321
1322 lock->force_write = 1;
1323 flag = log_all_ref_updates;
1324 log_all_ref_updates = 0;
1325 if (write_ref_sha1(lock, orig_sha1, NULL))
1326 error("unable to write current sha1 into %s", oldref);
1327 log_all_ref_updates = flag;
1328
1329 rollbacklog:
1330 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1331 error("unable to restore logfile %s from %s: %s",
1332 oldref, newref, strerror(errno));
1333 if (!logmoved && log &&
765c2258
PH
1334 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1335 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
c976d415
LH
1336 oldref, strerror(errno));
1337
1338 return 1;
1339}
1340
435fc852 1341int close_ref(struct ref_lock *lock)
b531394d
BC
1342{
1343 if (close_lock_file(lock->lk))
1344 return -1;
1345 lock->lock_fd = -1;
1346 return 0;
1347}
1348
435fc852 1349int commit_ref(struct ref_lock *lock)
b531394d
BC
1350{
1351 if (commit_lock_file(lock->lk))
1352 return -1;
1353 lock->lock_fd = -1;
1354 return 0;
1355}
1356
e5f38ec3 1357void unlock_ref(struct ref_lock *lock)
4bd18c43 1358{
4ed7cd3a
BC
1359 /* Do not free lock->lk -- atexit() still looks at them */
1360 if (lock->lk)
1361 rollback_lock_file(lock->lk);
434cd0cd 1362 free(lock->ref_name);
1655707c 1363 free(lock->orig_ref_name);
4bd18c43
SP
1364 free(lock);
1365}
1366
0ec29a47
JH
1367/*
1368 * copy the reflog message msg to buf, which has been allocated sufficiently
1369 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1370 * because reflog file is one line per entry.
1371 */
1372static int copy_msg(char *buf, const char *msg)
1373{
1374 char *cp = buf;
1375 char c;
1376 int wasspace = 1;
1377
1378 *cp++ = '\t';
1379 while ((c = *msg++)) {
1380 if (wasspace && isspace(c))
1381 continue;
1382 wasspace = isspace(c);
1383 if (wasspace)
1384 c = ' ';
1385 *cp++ = c;
1386 }
1387 while (buf < cp && isspace(cp[-1]))
1388 cp--;
1389 *cp++ = '\n';
1390 return cp - buf;
1391}
1392
157aaea5 1393int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
6de08ae6 1394{
859c3017 1395 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1396
157aaea5 1397 git_snpath(logfile, bufsize, "logs/%s", ref_name);
4057deb5 1398 if (log_all_ref_updates &&
cc44c765
JH
1399 (!prefixcmp(ref_name, "refs/heads/") ||
1400 !prefixcmp(ref_name, "refs/remotes/") ||
b2e256b0 1401 !prefixcmp(ref_name, "refs/notes/") ||
bd104db1 1402 !strcmp(ref_name, "HEAD"))) {
157aaea5 1403 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1404 return error("unable to create directory for %s",
157aaea5 1405 logfile);
6de08ae6
SP
1406 oflags |= O_CREAT;
1407 }
1408
157aaea5 1409 logfd = open(logfile, oflags, 0666);
6de08ae6 1410 if (logfd < 0) {
1974bf62 1411 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1412 return 0;
3b463c3f
JH
1413
1414 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1415 if (remove_empty_directories(logfile)) {
3b463c3f 1416 return error("There are still logs under '%s'",
157aaea5 1417 logfile);
3b463c3f 1418 }
157aaea5 1419 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1420 }
1421
1422 if (logfd < 0)
1423 return error("Unable to append to %s: %s",
157aaea5 1424 logfile, strerror(errno));
6de08ae6
SP
1425 }
1426
157aaea5 1427 adjust_shared_perm(logfile);
859c3017
EM
1428 close(logfd);
1429 return 0;
1430}
443b92b6 1431
859c3017
EM
1432static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1433 const unsigned char *new_sha1, const char *msg)
1434{
1435 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1436 unsigned maxlen, len;
1437 int msglen;
157aaea5 1438 char log_file[PATH_MAX];
859c3017
EM
1439 char *logrec;
1440 const char *committer;
1441
1442 if (log_all_ref_updates < 0)
1443 log_all_ref_updates = !is_bare_repository();
1444
157aaea5 1445 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
859c3017
EM
1446 if (result)
1447 return result;
1448
1449 logfd = open(log_file, oflags);
1450 if (logfd < 0)
1451 return 0;
0ec29a47 1452 msglen = msg ? strlen(msg) : 0;
774751a8 1453 committer = git_committer_info(0);
8ac65937
JH
1454 maxlen = strlen(committer) + msglen + 100;
1455 logrec = xmalloc(maxlen);
1456 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1457 sha1_to_hex(old_sha1),
1458 sha1_to_hex(new_sha1),
8ac65937
JH
1459 committer);
1460 if (msglen)
0ec29a47 1461 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1462 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1463 free(logrec);
91c8d590 1464 if (close(logfd) != 0 || written != len)
9a13f0b7 1465 return error("Unable to append to %s", log_file);
6de08ae6
SP
1466 return 0;
1467}
1468
c3b0dec5
LT
1469static int is_branch(const char *refname)
1470{
1471 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1472}
1473
4bd18c43
SP
1474int write_ref_sha1(struct ref_lock *lock,
1475 const unsigned char *sha1, const char *logmsg)
1476{
1477 static char term = '\n';
c3b0dec5 1478 struct object *o;
4bd18c43
SP
1479
1480 if (!lock)
95fc7512 1481 return -1;
a89fccd2 1482 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1483 unlock_ref(lock);
1484 return 0;
95fc7512 1485 }
c3b0dec5
LT
1486 o = parse_object(sha1);
1487 if (!o) {
7be8b3ba 1488 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
1489 lock->ref_name, sha1_to_hex(sha1));
1490 unlock_ref(lock);
1491 return -1;
1492 }
1493 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1494 error("Trying to write non-commit object %s to branch %s",
1495 sha1_to_hex(sha1), lock->ref_name);
1496 unlock_ref(lock);
1497 return -1;
1498 }
93822c22
AW
1499 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1500 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1501 || close_ref(lock) < 0) {
c33d5174 1502 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1503 unlock_ref(lock);
1504 return -1;
1505 }
5e290ff7 1506 invalidate_cached_refs();
bd104db1
NP
1507 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1508 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1509 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1510 unlock_ref(lock);
1511 return -1;
1512 }
605fac8b
NP
1513 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1514 /*
1515 * Special hack: If a branch is updated directly and HEAD
1516 * points to it (may happen on the remote side of a push
1517 * for example) then logically the HEAD reflog should be
1518 * updated too.
1519 * A generic solution implies reverse symref information,
1520 * but finding all symrefs pointing to the given branch
1521 * would be rather costly for this rare event (the direct
1522 * update of a branch) to be worth it. So let's cheat and
1523 * check with HEAD only which should cover 99% of all usage
1524 * scenarios (even 100% of the default ones).
1525 */
1526 unsigned char head_sha1[20];
1527 int head_flag;
1528 const char *head_ref;
1529 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1530 if (head_ref && (head_flag & REF_ISSYMREF) &&
1531 !strcmp(head_ref, lock->ref_name))
1532 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1533 }
b531394d 1534 if (commit_ref(lock)) {
434cd0cd 1535 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1536 unlock_ref(lock);
1537 return -1;
1538 }
4bd18c43
SP
1539 unlock_ref(lock);
1540 return 0;
95fc7512 1541}
d556fae2 1542
8b5157e4
NP
1543int create_symref(const char *ref_target, const char *refs_heads_master,
1544 const char *logmsg)
41b625b0
NP
1545{
1546 const char *lockpath;
1547 char ref[1000];
1548 int fd, len, written;
a4f34cbb 1549 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1550 unsigned char old_sha1[20], new_sha1[20];
1551
1552 if (logmsg && read_ref(ref_target, old_sha1))
1553 hashclr(old_sha1);
41b625b0 1554
d48744d1
JH
1555 if (safe_create_leading_directories(git_HEAD) < 0)
1556 return error("unable to create directory for %s", git_HEAD);
1557
41b625b0
NP
1558#ifndef NO_SYMLINK_HEAD
1559 if (prefer_symlink_refs) {
1560 unlink(git_HEAD);
1561 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1562 goto done;
41b625b0
NP
1563 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1564 }
1565#endif
1566
1567 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1568 if (sizeof(ref) <= len) {
1569 error("refname too long: %s", refs_heads_master);
47fc52e2 1570 goto error_free_return;
41b625b0
NP
1571 }
1572 lockpath = mkpath("%s.lock", git_HEAD);
1573 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1574 if (fd < 0) {
1575 error("Unable to open %s for writing", lockpath);
47fc52e2 1576 goto error_free_return;
41b625b0
NP
1577 }
1578 written = write_in_full(fd, ref, len);
91c8d590 1579 if (close(fd) != 0 || written != len) {
41b625b0 1580 error("Unable to write to %s", lockpath);
47fc52e2 1581 goto error_unlink_return;
41b625b0
NP
1582 }
1583 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1584 error("Unable to create %s", git_HEAD);
47fc52e2 1585 goto error_unlink_return;
41b625b0
NP
1586 }
1587 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1588 error("Unable to fix permissions on %s", lockpath);
47fc52e2 1589 error_unlink_return:
691f1a28 1590 unlink_or_warn(lockpath);
47fc52e2
JH
1591 error_free_return:
1592 free(git_HEAD);
1593 return -1;
41b625b0 1594 }
8b5157e4 1595
ee96d11b 1596#ifndef NO_SYMLINK_HEAD
8b5157e4 1597 done:
ee96d11b 1598#endif
8b5157e4
NP
1599 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1600 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1601
47fc52e2 1602 free(git_HEAD);
41b625b0
NP
1603 return 0;
1604}
1605
16d7cc90
JH
1606static char *ref_msg(const char *line, const char *endp)
1607{
1608 const char *ep;
16d7cc90 1609 line += 82;
182af834
PH
1610 ep = memchr(line, '\n', endp - line);
1611 if (!ep)
1612 ep = endp;
1613 return xmemdupz(line, ep - line);
16d7cc90
JH
1614}
1615
1616int 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 1617{
e5229042 1618 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1619 char *tz_c;
e29cb53a 1620 int logfd, tz, reccnt = 0;
d556fae2
SP
1621 struct stat st;
1622 unsigned long date;
e5229042 1623 unsigned char logged_sha1[20];
cb48cb58 1624 void *log_mapped;
dc49cd76 1625 size_t mapsz;
d556fae2
SP
1626
1627 logfile = git_path("logs/%s", ref);
1628 logfd = open(logfile, O_RDONLY, 0);
1629 if (logfd < 0)
d824cbba 1630 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
1631 fstat(logfd, &st);
1632 if (!st.st_size)
1633 die("Log %s is empty.", logfile);
dc49cd76
SP
1634 mapsz = xsize_t(st.st_size);
1635 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1636 logdata = log_mapped;
d556fae2
SP
1637 close(logfd);
1638
e5229042 1639 lastrec = NULL;
d556fae2
SP
1640 rec = logend = logdata + st.st_size;
1641 while (logdata < rec) {
e29cb53a 1642 reccnt++;
d556fae2
SP
1643 if (logdata < rec && *(rec-1) == '\n')
1644 rec--;
e5229042
SP
1645 lastgt = NULL;
1646 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1647 rec--;
e5229042
SP
1648 if (*rec == '>')
1649 lastgt = rec;
1650 }
1651 if (!lastgt)
d556fae2 1652 die("Log %s is corrupt.", logfile);
e5229042 1653 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1654 if (date <= at_time || cnt == 0) {
76a44c5c 1655 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1656 if (msg)
1657 *msg = ref_msg(rec, logend);
1658 if (cutoff_time)
1659 *cutoff_time = date;
1660 if (cutoff_tz)
1661 *cutoff_tz = tz;
1662 if (cutoff_cnt)
76a44c5c 1663 *cutoff_cnt = reccnt - 1;
e5229042
SP
1664 if (lastrec) {
1665 if (get_sha1_hex(lastrec, logged_sha1))
1666 die("Log %s is corrupt.", logfile);
1667 if (get_sha1_hex(rec + 41, sha1))
1668 die("Log %s is corrupt.", logfile);
a89fccd2 1669 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1670 warning("Log %s has gap after %s.",
73013afd 1671 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1672 }
e5f38ec3
JH
1673 }
1674 else if (date == at_time) {
e5229042
SP
1675 if (get_sha1_hex(rec + 41, sha1))
1676 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1677 }
1678 else {
e5229042
SP
1679 if (get_sha1_hex(rec + 41, logged_sha1))
1680 die("Log %s is corrupt.", logfile);
a89fccd2 1681 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1682 warning("Log %s unexpectedly ended on %s.",
73013afd 1683 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1684 }
1685 }
dc49cd76 1686 munmap(log_mapped, mapsz);
d556fae2
SP
1687 return 0;
1688 }
e5229042 1689 lastrec = rec;
ab2a1a32
JH
1690 if (cnt > 0)
1691 cnt--;
d556fae2
SP
1692 }
1693
e5229042
SP
1694 rec = logdata;
1695 while (rec < logend && *rec != '>' && *rec != '\n')
1696 rec++;
1697 if (rec == logend || *rec == '\n')
d556fae2 1698 die("Log %s is corrupt.", logfile);
e5229042 1699 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1700 tz = strtoul(tz_c, NULL, 10);
1701 if (get_sha1_hex(logdata, sha1))
1702 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1703 if (is_null_sha1(sha1)) {
1704 if (get_sha1_hex(logdata + 41, sha1))
1705 die("Log %s is corrupt.", logfile);
1706 }
16d7cc90
JH
1707 if (msg)
1708 *msg = ref_msg(logdata, logend);
dc49cd76 1709 munmap(log_mapped, mapsz);
16d7cc90
JH
1710
1711 if (cutoff_time)
1712 *cutoff_time = date;
1713 if (cutoff_tz)
1714 *cutoff_tz = tz;
1715 if (cutoff_cnt)
1716 *cutoff_cnt = reccnt;
1717 return 1;
d556fae2 1718}
2ff81662 1719
101d15e0 1720int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
1721{
1722 const char *logfile;
1723 FILE *logfp;
8ca78803 1724 struct strbuf sb = STRBUF_INIT;
2266bf27 1725 int ret = 0;
2ff81662
JH
1726
1727 logfile = git_path("logs/%s", ref);
1728 logfp = fopen(logfile, "r");
1729 if (!logfp)
883d60fa 1730 return -1;
101d15e0
JH
1731
1732 if (ofs) {
1733 struct stat statbuf;
1734 if (fstat(fileno(logfp), &statbuf) ||
1735 statbuf.st_size < ofs ||
1736 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 1737 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 1738 fclose(logfp);
8ca78803 1739 strbuf_release(&sb);
101d15e0 1740 return -1;
9d33f7c2 1741 }
101d15e0
JH
1742 }
1743
8ca78803 1744 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 1745 unsigned char osha1[20], nsha1[20];
883d60fa
JS
1746 char *email_end, *message;
1747 unsigned long timestamp;
8ca78803 1748 int tz;
2ff81662
JH
1749
1750 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
1751 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1752 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1753 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1754 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
1755 email_end[1] != ' ' ||
1756 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1757 !message || message[0] != ' ' ||
1758 (message[1] != '+' && message[1] != '-') ||
1759 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 1760 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 1761 continue; /* corrupt? */
883d60fa
JS
1762 email_end[1] = '\0';
1763 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
1764 if (message[6] != '\t')
1765 message += 6;
1766 else
1767 message += 7;
8ca78803
RS
1768 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1769 cb_data);
883d60fa 1770 if (ret)
2266bf27 1771 break;
2ff81662
JH
1772 }
1773 fclose(logfp);
8ca78803 1774 strbuf_release(&sb);
2266bf27 1775 return ret;
2ff81662 1776}
e29cb53a 1777
101d15e0
JH
1778int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1779{
1780 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1781}
1782
eb8381c8
NP
1783static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1784{
1785 DIR *dir = opendir(git_path("logs/%s", base));
fcee5a14 1786 int retval = 0;
eb8381c8
NP
1787
1788 if (dir) {
1789 struct dirent *de;
1790 int baselen = strlen(base);
1791 char *log = xmalloc(baselen + 257);
1792
1793 memcpy(log, base, baselen);
1794 if (baselen && base[baselen-1] != '/')
1795 log[baselen++] = '/';
1796
1797 while ((de = readdir(dir)) != NULL) {
1798 struct stat st;
1799 int namelen;
1800
1801 if (de->d_name[0] == '.')
1802 continue;
1803 namelen = strlen(de->d_name);
1804 if (namelen > 255)
1805 continue;
1806 if (has_extension(de->d_name, ".lock"))
1807 continue;
1808 memcpy(log + baselen, de->d_name, namelen+1);
1809 if (stat(git_path("logs/%s", log), &st) < 0)
1810 continue;
1811 if (S_ISDIR(st.st_mode)) {
1812 retval = do_for_each_reflog(log, fn, cb_data);
1813 } else {
1814 unsigned char sha1[20];
1815 if (!resolve_ref(log, sha1, 0, NULL))
1816 retval = error("bad ref for %s", log);
1817 else
1818 retval = fn(log, sha1, 0, cb_data);
1819 }
1820 if (retval)
1821 break;
1822 }
1823 free(log);
1824 closedir(dir);
1825 }
acb39f64 1826 else if (*base)
fcee5a14 1827 return errno;
eb8381c8
NP
1828 return retval;
1829}
1830
1831int for_each_reflog(each_ref_fn fn, void *cb_data)
1832{
1833 return do_for_each_reflog("", fn, cb_data);
1834}
3d9f037c
CR
1835
1836int update_ref(const char *action, const char *refname,
1837 const unsigned char *sha1, const unsigned char *oldval,
1838 int flags, enum action_on_err onerr)
1839{
1840 static struct ref_lock *lock;
1841 lock = lock_any_ref_for_update(refname, oldval, flags);
1842 if (!lock) {
1843 const char *str = "Cannot lock the ref '%s'.";
1844 switch (onerr) {
1845 case MSG_ON_ERR: error(str, refname); break;
1846 case DIE_ON_ERR: die(str, refname); break;
1847 case QUIET_ON_ERR: break;
1848 }
1849 return 1;
1850 }
1851 if (write_ref_sha1(lock, sha1, action) < 0) {
1852 const char *str = "Cannot update the ref '%s'.";
1853 switch (onerr) {
1854 case MSG_ON_ERR: error(str, refname); break;
1855 case DIE_ON_ERR: die(str, refname); break;
1856 case QUIET_ON_ERR: break;
1857 }
1858 return 1;
1859 }
1860 return 0;
1861}
cda69f48 1862
c17b2294
JH
1863int ref_exists(char *refname)
1864{
1865 unsigned char sha1[20];
1866 return !!resolve_ref(refname, sha1, 1, NULL);
1867}
1868
5483f799 1869struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
1870{
1871 for ( ; list; list = list->next)
1872 if (!strcmp(list->name, name))
5483f799 1873 return (struct ref *)list;
cda69f48
JK
1874 return NULL;
1875}
7c2b3029
JK
1876
1877/*
1878 * generate a format suitable for scanf from a ref_rev_parse_rules
1879 * rule, that is replace the "%.*s" spec with a "%s" spec
1880 */
1881static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1882{
1883 char *spec;
1884
1885 spec = strstr(rule, "%.*s");
1886 if (!spec || strstr(spec + 4, "%.*s"))
1887 die("invalid rule in ref_rev_parse_rules: %s", rule);
1888
1889 /* copy all until spec */
1890 strncpy(scanf_fmt, rule, spec - rule);
1891 scanf_fmt[spec - rule] = '\0';
1892 /* copy new spec */
1893 strcat(scanf_fmt, "%s");
1894 /* copy remaining rule */
1895 strcat(scanf_fmt, spec + 4);
1896
1897 return;
1898}
1899
6e7b3309 1900char *shorten_unambiguous_ref(const char *ref, int strict)
7c2b3029
JK
1901{
1902 int i;
1903 static char **scanf_fmts;
1904 static int nr_rules;
1905 char *short_name;
1906
1907 /* pre generate scanf formats from ref_rev_parse_rules[] */
1908 if (!nr_rules) {
1909 size_t total_len = 0;
1910
1911 /* the rule list is NULL terminated, count them first */
1912 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1913 /* no +1 because strlen("%s") < strlen("%.*s") */
1914 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1915
1916 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1917
1918 total_len = 0;
1919 for (i = 0; i < nr_rules; i++) {
1920 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1921 + total_len;
1922 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1923 total_len += strlen(ref_rev_parse_rules[i]);
1924 }
1925 }
1926
1927 /* bail out if there are no rules */
1928 if (!nr_rules)
1929 return xstrdup(ref);
1930
1931 /* buffer for scanf result, at most ref must fit */
1932 short_name = xstrdup(ref);
1933
1934 /* skip first rule, it will always match */
1935 for (i = nr_rules - 1; i > 0 ; --i) {
1936 int j;
6e7b3309 1937 int rules_to_fail = i;
7c2b3029
JK
1938 int short_name_len;
1939
1940 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1941 continue;
1942
1943 short_name_len = strlen(short_name);
1944
6e7b3309
BW
1945 /*
1946 * in strict mode, all (except the matched one) rules
1947 * must fail to resolve to a valid non-ambiguous ref
1948 */
1949 if (strict)
1950 rules_to_fail = nr_rules;
1951
7c2b3029
JK
1952 /*
1953 * check if the short name resolves to a valid ref,
1954 * but use only rules prior to the matched one
1955 */
6e7b3309 1956 for (j = 0; j < rules_to_fail; j++) {
7c2b3029
JK
1957 const char *rule = ref_rev_parse_rules[j];
1958 unsigned char short_objectname[20];
1959 char refname[PATH_MAX];
1960
6e7b3309
BW
1961 /* skip matched rule */
1962 if (i == j)
1963 continue;
1964
7c2b3029
JK
1965 /*
1966 * the short name is ambiguous, if it resolves
1967 * (with this previous rule) to a valid ref
1968 * read_ref() returns 0 on success
1969 */
1970 mksnpath(refname, sizeof(refname),
1971 rule, short_name_len, short_name);
1972 if (!read_ref(refname, short_objectname))
1973 break;
1974 }
1975
1976 /*
1977 * short name is non-ambiguous if all previous rules
1978 * haven't resolved to a valid ref
1979 */
6e7b3309 1980 if (j == rules_to_fail)
7c2b3029
JK
1981 return short_name;
1982 }
1983
1984 free(short_name);
1985 return xstrdup(ref);
1986}