Allocate cached_refs objects dynamically
[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;
e5dbf605 160} *cached_refs, *submodule_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
f130b116 174static void clear_cached_refs(struct cached_refs *ca)
e1e22e37 175{
5e290ff7
JH
176 if (ca->did_loose && ca->loose)
177 free_ref_list(ca->loose);
178 if (ca->did_packed && ca->packed)
179 free_ref_list(ca->packed);
180 ca->loose = ca->packed = NULL;
181 ca->did_loose = ca->did_packed = 0;
f130b116
MH
182}
183
e5dbf605
MH
184struct cached_refs *create_cached_refs(void)
185{
186 struct cached_refs *refs;
187 refs = xmalloc(sizeof(struct cached_refs));
188 refs->did_loose = refs->did_packed = 0;
189 refs->loose = refs->packed = NULL;
190 return refs;
191}
192
4349a668
MH
193/*
194 * Return a pointer to a cached_refs for the specified submodule. For
195 * the main repository, use submodule==NULL. The returned structure
196 * will be allocated and initialized but not necessarily populated; it
197 * should not be freed.
198 */
199static struct cached_refs *get_cached_refs(const char *submodule)
200{
e5dbf605
MH
201 if (!submodule) {
202 if (!cached_refs)
203 cached_refs = create_cached_refs();
204 return cached_refs;
205 } else {
206 if (!submodule_refs)
207 submodule_refs = create_cached_refs();
208 else
209 /* For now, don't reuse the refs cache for submodules. */
210 clear_cached_refs(submodule_refs);
211 return submodule_refs;
4349a668
MH
212 }
213}
214
f130b116
MH
215static void invalidate_cached_refs(void)
216{
4349a668 217 clear_cached_refs(get_cached_refs(NULL));
5e290ff7 218}
e1e22e37 219
db4dd93a 220static struct ref_list *read_packed_refs(FILE *f)
f4204ab9
JH
221{
222 struct ref_list *list = NULL;
223 struct ref_list *last = NULL;
224 char refline[PATH_MAX];
225 int flag = REF_ISPACKED;
226
227 while (fgets(refline, sizeof(refline), f)) {
228 unsigned char sha1[20];
229 const char *name;
230 static const char header[] = "# pack-refs with:";
231
232 if (!strncmp(refline, header, sizeof(header)-1)) {
233 const char *traits = refline + sizeof(header) - 1;
234 if (strstr(traits, " peeled "))
235 flag |= REF_KNOWS_PEELED;
236 /* perhaps other traits later as well */
237 continue;
238 }
239
240 name = parse_ref_line(refline, sha1);
241 if (name) {
242 list = add_ref(name, sha1, flag, list, &last);
243 continue;
244 }
245 if (last &&
246 refline[0] == '^' &&
247 strlen(refline) == 42 &&
248 refline[41] == '\n' &&
249 !get_sha1_hex(refline + 1, sha1))
250 hashcpy(last->peeled, sha1);
251 }
db4dd93a 252 return sort_ref_list(list);
f4204ab9
JH
253}
254
e142a3c6
DB
255void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
256{
257 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
258}
259
260void clear_extra_refs(void)
261{
262 free_ref_list(extra_refs);
263 extra_refs = NULL;
264}
265
0bad611b 266static struct ref_list *get_packed_refs(const char *submodule)
5e290ff7 267{
4349a668 268 struct cached_refs *refs = get_cached_refs(submodule);
0bad611b 269
4349a668
MH
270 if (!refs->did_packed) {
271 const char *packed_refs_file;
272 FILE *f;
273
274 if (submodule)
275 packed_refs_file = git_path_submodule(submodule, "packed-refs");
276 else
277 packed_refs_file = git_path("packed-refs");
278 f = fopen(packed_refs_file, "r");
0bad611b 279 refs->packed = NULL;
e1e22e37 280 if (f) {
db4dd93a 281 refs->packed = read_packed_refs(f);
e1e22e37 282 fclose(f);
e1e22e37 283 }
0bad611b 284 refs->did_packed = 1;
e1e22e37 285 }
0bad611b 286 return refs->packed;
e1e22e37
LT
287}
288
0bad611b
HV
289static struct ref_list *get_ref_dir(const char *submodule, const char *base,
290 struct ref_list *list)
e1e22e37 291{
0bad611b
HV
292 DIR *dir;
293 const char *path;
294
295 if (submodule)
296 path = git_path_submodule(submodule, "%s", base);
297 else
298 path = git_path("%s", base);
299
300
301 dir = opendir(path);
e1e22e37
LT
302
303 if (dir) {
304 struct dirent *de;
305 int baselen = strlen(base);
ed378ec7 306 char *ref = xmalloc(baselen + 257);
e1e22e37 307
ed378ec7 308 memcpy(ref, base, baselen);
e1e22e37 309 if (baselen && base[baselen-1] != '/')
ed378ec7 310 ref[baselen++] = '/';
e1e22e37
LT
311
312 while ((de = readdir(dir)) != NULL) {
313 unsigned char sha1[20];
314 struct stat st;
8da19775 315 int flag;
e1e22e37 316 int namelen;
0bad611b 317 const char *refdir;
e1e22e37
LT
318
319 if (de->d_name[0] == '.')
320 continue;
321 namelen = strlen(de->d_name);
322 if (namelen > 255)
323 continue;
324 if (has_extension(de->d_name, ".lock"))
325 continue;
ed378ec7 326 memcpy(ref + baselen, de->d_name, namelen+1);
0bad611b
HV
327 refdir = submodule
328 ? git_path_submodule(submodule, "%s", ref)
329 : git_path("%s", ref);
330 if (stat(refdir, &st) < 0)
e1e22e37
LT
331 continue;
332 if (S_ISDIR(st.st_mode)) {
0bad611b 333 list = get_ref_dir(submodule, ref, list);
e1e22e37
LT
334 continue;
335 }
0bad611b 336 if (submodule) {
f8948e2f 337 hashclr(sha1);
0bad611b
HV
338 flag = 0;
339 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
340 hashclr(sha1);
341 flag |= REF_BROKEN;
342 }
343 } else
344 if (!resolve_ref(ref, sha1, 1, &flag)) {
345 hashclr(sha1);
346 flag |= REF_BROKEN;
347 }
f4204ab9 348 list = add_ref(ref, sha1, flag, list, NULL);
e1e22e37 349 }
ed378ec7 350 free(ref);
e1e22e37
LT
351 closedir(dir);
352 }
c774aab9 353 return sort_ref_list(list);
e1e22e37
LT
354}
355
f8948e2f 356struct warn_if_dangling_data {
3cf6134a 357 FILE *fp;
f8948e2f
JH
358 const char *refname;
359 const char *msg_fmt;
360};
361
362static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
363 int flags, void *cb_data)
364{
365 struct warn_if_dangling_data *d = cb_data;
366 const char *resolves_to;
367 unsigned char junk[20];
368
369 if (!(flags & REF_ISSYMREF))
370 return 0;
371
372 resolves_to = resolve_ref(refname, junk, 0, NULL);
373 if (!resolves_to || strcmp(resolves_to, d->refname))
374 return 0;
375
3cf6134a 376 fprintf(d->fp, d->msg_fmt, refname);
f8948e2f
JH
377 return 0;
378}
379
3cf6134a 380void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
f8948e2f 381{
66dbfd55
GV
382 struct warn_if_dangling_data data;
383
384 data.fp = fp;
385 data.refname = refname;
386 data.msg_fmt = msg_fmt;
f8948e2f
JH
387 for_each_rawref(warn_if_dangling_symref, &data);
388}
389
0bad611b 390static struct ref_list *get_loose_refs(const char *submodule)
e1e22e37 391{
4349a668 392 struct cached_refs *refs = get_cached_refs(submodule);
0bad611b 393
4349a668
MH
394 if (!refs->did_loose) {
395 refs->loose = get_ref_dir(submodule, "refs", NULL);
396 refs->did_loose = 1;
e1e22e37 397 }
4349a668 398 return refs->loose;
e1e22e37
LT
399}
400
ca8db142
LT
401/* We allow "recursive" symbolic refs. Only within reason, though */
402#define MAXDEPTH 5
0ebde32c
LT
403#define MAXREFLEN (1024)
404
405static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
406{
407 FILE *f;
db4dd93a 408 struct ref_list *packed_refs;
0ebde32c
LT
409 struct ref_list *ref;
410 int retval;
411
412 strcpy(name + pathlen, "packed-refs");
413 f = fopen(name, "r");
414 if (!f)
415 return -1;
db4dd93a 416 packed_refs = read_packed_refs(f);
0ebde32c 417 fclose(f);
db4dd93a 418 ref = packed_refs;
0ebde32c
LT
419 retval = -1;
420 while (ref) {
421 if (!strcmp(ref->name, refname)) {
422 retval = 0;
423 memcpy(result, ref->sha1, 20);
424 break;
425 }
426 ref = ref->next;
427 }
db4dd93a 428 free_ref_list(packed_refs);
0ebde32c
LT
429 return retval;
430}
431
432static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
433{
434 int fd, len = strlen(refname);
435 char buffer[128], *p;
436
437 if (recursion > MAXDEPTH || len > MAXREFLEN)
438 return -1;
439 memcpy(name + pathlen, refname, len+1);
440 fd = open(name, O_RDONLY);
441 if (fd < 0)
442 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
443
444 len = read(fd, buffer, sizeof(buffer)-1);
445 close(fd);
446 if (len < 0)
447 return -1;
448 while (len && isspace(buffer[len-1]))
449 len--;
450 buffer[len] = 0;
451
452 /* Was it a detached head or an old-fashioned symlink? */
453 if (!get_sha1_hex(buffer, result))
454 return 0;
455
456 /* Symref? */
457 if (strncmp(buffer, "ref:", 4))
458 return -1;
459 p = buffer + 4;
460 while (isspace(*p))
461 p++;
462
463 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
464}
465
466int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
467{
468 int len = strlen(path), retval;
469 char *gitdir;
842abf06 470 const char *tmp;
0ebde32c
LT
471
472 while (len && path[len-1] == '/')
473 len--;
474 if (!len)
475 return -1;
476 gitdir = xmalloc(len + MAXREFLEN + 8);
477 memcpy(gitdir, path, len);
842abf06
LH
478 memcpy(gitdir + len, "/.git", 6);
479 len += 5;
480
481 tmp = read_gitfile_gently(gitdir);
482 if (tmp) {
483 free(gitdir);
484 len = strlen(tmp);
485 gitdir = xmalloc(len + MAXREFLEN + 3);
486 memcpy(gitdir, tmp, len);
487 }
488 gitdir[len] = '/';
489 gitdir[++len] = '\0';
490 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
0ebde32c
LT
491 free(gitdir);
492 return retval;
493}
ca8db142 494
4886b89f
CC
495/*
496 * If the "reading" argument is set, this function finds out what _object_
497 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
498 * has to exist, and if it is symbolic, it has to point at an existing ref,
499 * because the "read" goes through the symref to the ref it points at.
500 *
501 * The access that is not "reading" may often be "writing", but does not
502 * have to; it can be merely checking _where it leads to_. If it is a
503 * prelude to "writing" to the ref, a write to a symref that points at
504 * yet-to-be-born ref will create the real ref pointed by the symref.
505 * reading=0 allows the caller to check where such a symref leads to.
506 */
8da19775 507const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
8a65ff76 508{
0104ca09
HO
509 int depth = MAXDEPTH;
510 ssize_t len;
a876ed83 511 char buffer[256];
ed378ec7 512 static char ref_buffer[256];
ca8db142 513
8da19775
JH
514 if (flag)
515 *flag = 0;
516
a876ed83 517 for (;;) {
958a4789 518 char path[PATH_MAX];
a876ed83
JH
519 struct stat st;
520 char *buf;
521 int fd;
8a65ff76 522
a876ed83
JH
523 if (--depth < 0)
524 return NULL;
ca8db142 525
958a4789 526 git_snpath(path, sizeof(path), "%s", ref);
4886b89f 527 /* Special case: non-existing file. */
a876ed83 528 if (lstat(path, &st) < 0) {
0bad611b 529 struct ref_list *list = get_packed_refs(NULL);
434cd0cd 530 while (list) {
f4204ab9 531 if (!strcmp(ref, list->name)) {
434cd0cd 532 hashcpy(sha1, list->sha1);
8da19775
JH
533 if (flag)
534 *flag |= REF_ISPACKED;
434cd0cd
LT
535 return ref;
536 }
537 list = list->next;
538 }
a876ed83
JH
539 if (reading || errno != ENOENT)
540 return NULL;
e702496e 541 hashclr(sha1);
ed378ec7 542 return ref;
a876ed83 543 }
ca8db142 544
a876ed83
JH
545 /* Follow "normalized" - ie "refs/.." symlinks by hand */
546 if (S_ISLNK(st.st_mode)) {
547 len = readlink(path, buffer, sizeof(buffer)-1);
548 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
ed378ec7
LT
549 buffer[len] = 0;
550 strcpy(ref_buffer, buffer);
551 ref = ref_buffer;
8da19775
JH
552 if (flag)
553 *flag |= REF_ISSYMREF;
a876ed83
JH
554 continue;
555 }
ca8db142 556 }
a876ed83 557
7a21632f
DS
558 /* Is it a directory? */
559 if (S_ISDIR(st.st_mode)) {
560 errno = EISDIR;
561 return NULL;
562 }
563
a876ed83
JH
564 /*
565 * Anything else, just open it and try to use it as
566 * a ref
567 */
568 fd = open(path, O_RDONLY);
569 if (fd < 0)
570 return NULL;
93d26e4c 571 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83
JH
572 close(fd);
573
574 /*
575 * Is it a symbolic ref?
576 */
577 if (len < 4 || memcmp("ref:", buffer, 4))
578 break;
579 buf = buffer + 4;
580 len -= 4;
581 while (len && isspace(*buf))
582 buf++, len--;
583 while (len && isspace(buf[len-1]))
ed378ec7
LT
584 len--;
585 buf[len] = 0;
586 memcpy(ref_buffer, buf, len + 1);
587 ref = ref_buffer;
8da19775
JH
588 if (flag)
589 *flag |= REF_ISSYMREF;
8a65ff76 590 }
a876ed83
JH
591 if (len < 40 || get_sha1_hex(buffer, sha1))
592 return NULL;
ed378ec7 593 return ref;
a876ed83
JH
594}
595
d08bae7e
IL
596/* The argument to filter_refs */
597struct ref_filter {
598 const char *pattern;
599 each_ref_fn *fn;
600 void *cb_data;
601};
602
ed378ec7 603int read_ref(const char *ref, unsigned char *sha1)
a876ed83 604{
8da19775 605 if (resolve_ref(ref, sha1, 1, NULL))
a876ed83
JH
606 return 0;
607 return -1;
8a65ff76
LT
608}
609
f8948e2f 610#define DO_FOR_EACH_INCLUDE_BROKEN 01
ef06b918 611static int do_one_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 612 int flags, void *cb_data, struct ref_list *entry)
ef06b918
JH
613{
614 if (strncmp(base, entry->name, trim))
615 return 0;
e01de1c9 616
f8948e2f 617 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
e01de1c9
JH
618 if (entry->flag & REF_BROKEN)
619 return 0; /* ignore dangling symref */
f8948e2f
JH
620 if (!has_sha1_file(entry->sha1)) {
621 error("%s does not point to a valid object!", entry->name);
622 return 0;
623 }
ef06b918 624 }
0ae91be0 625 current_ref = entry;
ef06b918
JH
626 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
627}
628
d08bae7e
IL
629static int filter_refs(const char *ref, const unsigned char *sha, int flags,
630 void *data)
631{
632 struct ref_filter *filter = (struct ref_filter *)data;
633 if (fnmatch(filter->pattern, ref, 0))
634 return 0;
635 return filter->fn(ref, sha, flags, filter->cb_data);
636}
637
cf0adba7
JH
638int peel_ref(const char *ref, unsigned char *sha1)
639{
640 int flag;
641 unsigned char base[20];
642 struct object *o;
643
0ae91be0
SP
644 if (current_ref && (current_ref->name == ref
645 || !strcmp(current_ref->name, ref))) {
646 if (current_ref->flag & REF_KNOWS_PEELED) {
647 hashcpy(sha1, current_ref->peeled);
648 return 0;
649 }
650 hashcpy(base, current_ref->sha1);
651 goto fallback;
652 }
653
cf0adba7
JH
654 if (!resolve_ref(ref, base, 1, &flag))
655 return -1;
656
657 if ((flag & REF_ISPACKED)) {
0bad611b 658 struct ref_list *list = get_packed_refs(NULL);
cf0adba7
JH
659
660 while (list) {
f4204ab9
JH
661 if (!strcmp(list->name, ref)) {
662 if (list->flag & REF_KNOWS_PEELED) {
663 hashcpy(sha1, list->peeled);
664 return 0;
665 }
666 /* older pack-refs did not leave peeled ones */
667 break;
cf0adba7
JH
668 }
669 list = list->next;
670 }
cf0adba7
JH
671 }
672
0ae91be0 673fallback:
cf0adba7 674 o = parse_object(base);
8c87dc77 675 if (o && o->type == OBJ_TAG) {
cf0adba7
JH
676 o = deref_tag(o, ref, 0);
677 if (o) {
678 hashcpy(sha1, o->sha1);
679 return 0;
680 }
681 }
682 return -1;
683}
684
0bad611b
HV
685static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
686 int trim, int flags, void *cb_data)
8a65ff76 687{
0ae91be0 688 int retval = 0;
0bad611b
HV
689 struct ref_list *packed = get_packed_refs(submodule);
690 struct ref_list *loose = get_loose_refs(submodule);
8a65ff76 691
e142a3c6
DB
692 struct ref_list *extra;
693
694 for (extra = extra_refs; extra; extra = extra->next)
f8948e2f 695 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
e142a3c6 696
e1e22e37
LT
697 while (packed && loose) {
698 struct ref_list *entry;
699 int cmp = strcmp(packed->name, loose->name);
700 if (!cmp) {
701 packed = packed->next;
702 continue;
6cada6a9 703 }
e1e22e37
LT
704 if (cmp > 0) {
705 entry = loose;
706 loose = loose->next;
707 } else {
708 entry = packed;
709 packed = packed->next;
710 }
f8948e2f 711 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
e1e22e37 712 if (retval)
0ae91be0 713 goto end_each;
e1e22e37 714 }
8a65ff76 715
ef06b918 716 for (packed = packed ? packed : loose; packed; packed = packed->next) {
f8948e2f 717 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
ef06b918 718 if (retval)
0ae91be0 719 goto end_each;
8a65ff76 720 }
0ae91be0
SP
721
722end_each:
723 current_ref = NULL;
724 return retval;
8a65ff76
LT
725}
726
0bad611b
HV
727
728static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
729{
730 unsigned char sha1[20];
8da19775
JH
731 int flag;
732
0bad611b
HV
733 if (submodule) {
734 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
735 return fn("HEAD", sha1, 0, cb_data);
736
737 return 0;
738 }
739
8da19775
JH
740 if (resolve_ref("HEAD", sha1, 1, &flag))
741 return fn("HEAD", sha1, flag, cb_data);
0bad611b 742
2f34ba32 743 return 0;
723c31fe
LT
744}
745
0bad611b
HV
746int head_ref(each_ref_fn fn, void *cb_data)
747{
748 return do_head_ref(NULL, fn, cb_data);
749}
750
9ef6aeb0
HV
751int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
752{
753 return do_head_ref(submodule, fn, cb_data);
754}
755
cb5d709f 756int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 757{
0bad611b 758 return do_for_each_ref(NULL, "refs/", fn, 0, 0, cb_data);
a62be77f
SE
759}
760
9ef6aeb0
HV
761int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
762{
763 return do_for_each_ref(submodule, "refs/", fn, 0, 0, cb_data);
a62be77f
SE
764}
765
2a8177b6
CC
766int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
767{
0bad611b 768 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
769}
770
9ef6aeb0
HV
771int for_each_ref_in_submodule(const char *submodule, const char *prefix,
772 each_ref_fn fn, void *cb_data)
773{
774 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
775}
776
cb5d709f 777int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 778{
2a8177b6 779 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
780}
781
9ef6aeb0
HV
782int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
783{
784 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
785}
786
cb5d709f 787int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 788{
2a8177b6 789 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
790}
791
9ef6aeb0
HV
792int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
793{
794 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
795}
796
cb5d709f 797int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 798{
2a8177b6 799 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
800}
801
9ef6aeb0
HV
802int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
803{
804 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
805}
806
29268700
CC
807int for_each_replace_ref(each_ref_fn fn, void *cb_data)
808{
0bad611b 809 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
810}
811
b09fe971
IL
812int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
813 const char *prefix, void *cb_data)
d08bae7e
IL
814{
815 struct strbuf real_pattern = STRBUF_INIT;
816 struct ref_filter filter;
d08bae7e
IL
817 int ret;
818
b09fe971 819 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 820 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
821 else if (prefix)
822 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
823 strbuf_addstr(&real_pattern, pattern);
824
894a9d33 825 if (!has_glob_specials(pattern)) {
9517e6b8 826 /* Append implied '/' '*' if not present. */
d08bae7e
IL
827 if (real_pattern.buf[real_pattern.len - 1] != '/')
828 strbuf_addch(&real_pattern, '/');
829 /* No need to check for '*', there is none. */
830 strbuf_addch(&real_pattern, '*');
831 }
832
833 filter.pattern = real_pattern.buf;
834 filter.fn = fn;
835 filter.cb_data = cb_data;
836 ret = for_each_ref(filter_refs, &filter);
837
838 strbuf_release(&real_pattern);
839 return ret;
840}
841
b09fe971
IL
842int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
843{
844 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
845}
846
f8948e2f
JH
847int for_each_rawref(each_ref_fn fn, void *cb_data)
848{
0bad611b 849 return do_for_each_ref(NULL, "refs/", fn, 0,
f8948e2f 850 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
851}
852
03feddd6
JH
853/*
854 * Make sure "ref" is something reasonable to have under ".git/refs/";
855 * We do not like it if:
856 *
857 * - any path component of it begins with ".", or
858 * - it has double dots "..", or
859 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
860 * - it ends with a "/".
3e262b95 861 * - it ends with ".lock"
a4c2e699 862 * - it contains a "\" (backslash)
03feddd6
JH
863 */
864
865static inline int bad_ref_char(int ch)
866{
8558fd9e 867 if (((unsigned) ch) <= ' ' ||
a4c2e699 868 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
8558fd9e
DB
869 return 1;
870 /* 2.13 Pattern Matching Notation */
871 if (ch == '?' || ch == '[') /* Unsupported */
872 return 1;
873 if (ch == '*') /* Supported at the end */
874 return 2;
875 return 0;
03feddd6
JH
876}
877
95fc7512
DB
878int check_ref_format(const char *ref)
879{
cbdffe40 880 int ch, level, bad_type, last;
abd2bde7 881 int ret = CHECK_REF_FORMAT_OK;
03feddd6
JH
882 const char *cp = ref;
883
884 level = 0;
885 while (1) {
886 while ((ch = *cp++) == '/')
887 ; /* tolerate duplicated slashes */
888 if (!ch)
5f7b202a
JH
889 /* should not end with slashes */
890 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
891
892 /* we are at the beginning of the path component */
8558fd9e 893 if (ch == '.')
5f7b202a 894 return CHECK_REF_FORMAT_ERROR;
8558fd9e
DB
895 bad_type = bad_ref_char(ch);
896 if (bad_type) {
abd2bde7
DB
897 if (bad_type == 2 && (!*cp || *cp == '/') &&
898 ret == CHECK_REF_FORMAT_OK)
899 ret = CHECK_REF_FORMAT_WILDCARD;
900 else
901 return CHECK_REF_FORMAT_ERROR;
8558fd9e 902 }
03feddd6 903
cbdffe40 904 last = ch;
03feddd6
JH
905 /* scan the rest of the path component */
906 while ((ch = *cp++) != 0) {
8558fd9e 907 bad_type = bad_ref_char(ch);
cbdffe40 908 if (bad_type)
08fbdb30 909 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
910 if (ch == '/')
911 break;
cbdffe40
JH
912 if (last == '.' && ch == '.')
913 return CHECK_REF_FORMAT_ERROR;
914 if (last == '@' && ch == '{')
5f7b202a 915 return CHECK_REF_FORMAT_ERROR;
cbdffe40 916 last = ch;
03feddd6
JH
917 }
918 level++;
919 if (!ch) {
cbdffe40
JH
920 if (ref <= cp - 2 && cp[-2] == '.')
921 return CHECK_REF_FORMAT_ERROR;
03feddd6 922 if (level < 2)
5f7b202a 923 return CHECK_REF_FORMAT_ONELEVEL;
3e262b95
SP
924 if (has_extension(ref, ".lock"))
925 return CHECK_REF_FORMAT_ERROR;
abd2bde7 926 return ret;
03feddd6
JH
927 }
928 }
95fc7512
DB
929}
930
4577e483 931const char *prettify_refname(const char *name)
a9c37a72 932{
a9c37a72
DB
933 return name + (
934 !prefixcmp(name, "refs/heads/") ? 11 :
935 !prefixcmp(name, "refs/tags/") ? 10 :
936 !prefixcmp(name, "refs/remotes/") ? 13 :
937 0);
938}
939
79803322
SP
940const char *ref_rev_parse_rules[] = {
941 "%.*s",
942 "refs/%.*s",
943 "refs/tags/%.*s",
944 "refs/heads/%.*s",
945 "refs/remotes/%.*s",
946 "refs/remotes/%.*s/HEAD",
947 NULL
948};
949
605b4978
SP
950const char *ref_fetch_rules[] = {
951 "%.*s",
952 "refs/%.*s",
953 "refs/heads/%.*s",
954 NULL
955};
956
79803322
SP
957int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
958{
959 const char **p;
960 const int abbrev_name_len = strlen(abbrev_name);
961
962 for (p = rules; *p; p++) {
963 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
964 return 1;
965 }
966 }
967
968 return 0;
969}
970
e5f38ec3 971static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
972 const unsigned char *old_sha1, int mustexist)
973{
8da19775 974 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 975 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
976 unlock_ref(lock);
977 return NULL;
978 }
a89fccd2 979 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 980 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
981 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
982 unlock_ref(lock);
983 return NULL;
984 }
985 return lock;
986}
987
7155b727 988static int remove_empty_directories(const char *file)
bc7127ef
JH
989{
990 /* we want to create a file but there is a directory there;
991 * if that is an empty directory (or a directory that contains
992 * only empty directories), remove them.
993 */
7155b727
JS
994 struct strbuf path;
995 int result;
bc7127ef 996
7155b727
JS
997 strbuf_init(&path, 20);
998 strbuf_addstr(&path, file);
999
a0f4afbe 1000 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1001
1002 strbuf_release(&path);
1003
1004 return result;
bc7127ef
JH
1005}
1006
c976d415
LH
1007static int is_refname_available(const char *ref, const char *oldref,
1008 struct ref_list *list, int quiet)
1009{
1010 int namlen = strlen(ref); /* e.g. 'foo/bar' */
1011 while (list) {
1012 /* list->name could be 'foo' or 'foo/bar/baz' */
1013 if (!oldref || strcmp(oldref, list->name)) {
1014 int len = strlen(list->name);
1015 int cmplen = (namlen < len) ? namlen : len;
1016 const char *lead = (namlen < len) ? list->name : ref;
1017 if (!strncmp(ref, list->name, cmplen) &&
1018 lead[cmplen] == '/') {
1019 if (!quiet)
1020 error("'%s' exists; cannot create '%s'",
1021 list->name, ref);
1022 return 0;
1023 }
1024 }
1025 list = list->next;
1026 }
1027 return 1;
1028}
1029
68db31cc 1030static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
4bd18c43 1031{
434cd0cd 1032 char *ref_file;
ed378ec7 1033 const char *orig_ref = ref;
4bd18c43 1034 struct ref_lock *lock;
5cc3cef9 1035 int last_errno = 0;
acd3b9ec 1036 int type, lflags;
4431fcc4 1037 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1038 int missing = 0;
4bd18c43
SP
1039
1040 lock = xcalloc(1, sizeof(struct ref_lock));
1041 lock->lock_fd = -1;
1042
68db31cc 1043 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
bc7127ef
JH
1044 if (!ref && errno == EISDIR) {
1045 /* we are trying to lock foo but we used to
1046 * have foo/bar which now does not exist;
1047 * it is normal for the empty directory 'foo'
1048 * to remain.
1049 */
1050 ref_file = git_path("%s", orig_ref);
5cc3cef9
JH
1051 if (remove_empty_directories(ref_file)) {
1052 last_errno = errno;
1053 error("there are still refs under '%s'", orig_ref);
1054 goto error_return;
1055 }
68db31cc 1056 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
bc7127ef 1057 }
68db31cc
SV
1058 if (type_p)
1059 *type_p = type;
ed378ec7 1060 if (!ref) {
5cc3cef9 1061 last_errno = errno;
818f477c 1062 error("unable to resolve reference %s: %s",
ed378ec7 1063 orig_ref, strerror(errno));
5cc3cef9 1064 goto error_return;
4bd18c43 1065 }
5bdd8d4a 1066 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1067 /* When the ref did not exist and we are creating it,
1068 * make sure there is no existing ref that is packed
1069 * whose name begins with our refname, nor a ref whose
1070 * name is a proper prefix of our refname.
1071 */
5bdd8d4a 1072 if (missing &&
0bad611b 1073 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
f475e08e 1074 last_errno = ENOTDIR;
c976d415 1075 goto error_return;
f475e08e 1076 }
22a3844e 1077
c33d5174 1078 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1079
acd3b9ec
JH
1080 lflags = LOCK_DIE_ON_ERROR;
1081 if (flags & REF_NODEREF) {
68db31cc 1082 ref = orig_ref;
acd3b9ec
JH
1083 lflags |= LOCK_NODEREF;
1084 }
434cd0cd 1085 lock->ref_name = xstrdup(ref);
1655707c 1086 lock->orig_ref_name = xstrdup(orig_ref);
7c1a278d 1087 ref_file = git_path("%s", ref);
5bdd8d4a 1088 if (missing)
68db31cc
SV
1089 lock->force_write = 1;
1090 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1091 lock->force_write = 1;
4bd18c43 1092
5cc3cef9
JH
1093 if (safe_create_leading_directories(ref_file)) {
1094 last_errno = errno;
1095 error("unable to create directory for %s", ref_file);
1096 goto error_return;
1097 }
4bd18c43 1098
acd3b9ec 1099 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1100 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1101
1102 error_return:
1103 unlock_ref(lock);
1104 errno = last_errno;
1105 return NULL;
4bd18c43
SP
1106}
1107
4431fcc4 1108struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
95fc7512 1109{
53cce84c 1110 char refpath[PATH_MAX];
95fc7512 1111 if (check_ref_format(ref))
4bd18c43 1112 return NULL;
53cce84c 1113 strcpy(refpath, mkpath("refs/%s", ref));
68db31cc 1114 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1115}
1116
68db31cc 1117struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
4bd18c43 1118{
5f7b202a 1119 switch (check_ref_format(ref)) {
5f7b202a 1120 default:
257f3020
JH
1121 return NULL;
1122 case 0:
1123 case CHECK_REF_FORMAT_ONELEVEL:
5f7b202a
JH
1124 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1125 }
c0277d15
JH
1126}
1127
26a063a1
JH
1128static struct lock_file packlock;
1129
c0277d15
JH
1130static int repack_without_ref(const char *refname)
1131{
1132 struct ref_list *list, *packed_ref_list;
1133 int fd;
1134 int found = 0;
c0277d15 1135
0bad611b 1136 packed_ref_list = get_packed_refs(NULL);
c0277d15
JH
1137 for (list = packed_ref_list; list; list = list->next) {
1138 if (!strcmp(refname, list->name)) {
1139 found = 1;
1140 break;
1141 }
1142 }
1143 if (!found)
1144 return 0;
c0277d15 1145 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1b018fd9
MV
1146 if (fd < 0) {
1147 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1148 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1149 }
c0277d15
JH
1150
1151 for (list = packed_ref_list; list; list = list->next) {
1152 char line[PATH_MAX + 100];
1153 int len;
1154
1155 if (!strcmp(refname, list->name))
1156 continue;
1157 len = snprintf(line, sizeof(line), "%s %s\n",
1158 sha1_to_hex(list->sha1), list->name);
1159 /* this should not happen but just being defensive */
1160 if (len > sizeof(line))
1161 die("too long a refname '%s'", list->name);
1162 write_or_die(fd, line, len);
1163 }
1164 return commit_lock_file(&packlock);
1165}
1166
eca35a25 1167int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1168{
1169 struct ref_lock *lock;
eca35a25 1170 int err, i = 0, ret = 0, flag = 0;
c0277d15 1171
68db31cc 1172 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1173 if (!lock)
1174 return 1;
045a476f 1175 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1176 /* loose */
eca35a25
MV
1177 const char *path;
1178
1179 if (!(delopt & REF_NODEREF)) {
1180 i = strlen(lock->lk->filename) - 5; /* .lock */
1181 lock->lk->filename[i] = 0;
1182 path = lock->lk->filename;
1183 } else {
9db56f71 1184 path = git_path("%s", refname);
eca35a25 1185 }
691f1a28
AR
1186 err = unlink_or_warn(path);
1187 if (err && errno != ENOENT)
c0277d15 1188 ret = 1;
691f1a28 1189
eca35a25
MV
1190 if (!(delopt & REF_NODEREF))
1191 lock->lk->filename[i] = '.';
c0277d15
JH
1192 }
1193 /* removing the loose one could have resurrected an earlier
1194 * packed one. Also, if it was not loose we need to repack
1195 * without it.
1196 */
1197 ret |= repack_without_ref(refname);
1198
691f1a28 1199 unlink_or_warn(git_path("logs/%s", lock->ref_name));
c0277d15
JH
1200 invalidate_cached_refs();
1201 unlock_ref(lock);
1202 return ret;
4bd18c43
SP
1203}
1204
765c2258
PH
1205/*
1206 * People using contrib's git-new-workdir have .git/logs/refs ->
1207 * /some/other/path/.git/logs/refs, and that may live on another device.
1208 *
1209 * IOW, to avoid cross device rename errors, the temporary renamed log must
1210 * live into logs/refs.
1211 */
1212#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1213
678d0f4c 1214int rename_ref(const char *oldref, const char *newref, const char *logmsg)
c976d415
LH
1215{
1216 static const char renamed_ref[] = "RENAMED-REF";
1217 unsigned char sha1[20], orig_sha1[20];
1218 int flag = 0, logmoved = 0;
1219 struct ref_lock *lock;
c976d415 1220 struct stat loginfo;
16c2bfbb 1221 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
eca35a25 1222 const char *symref = NULL;
c976d415 1223
450d4c0f 1224 if (log && S_ISLNK(loginfo.st_mode))
c976d415
LH
1225 return error("reflog for %s is a symlink", oldref);
1226
eca35a25
MV
1227 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1228 if (flag & REF_ISSYMREF)
fa58186c
MV
1229 return error("refname %s is a symbolic ref, renaming it is not supported",
1230 oldref);
eca35a25 1231 if (!symref)
c976d415
LH
1232 return error("refname %s not found", oldref);
1233
0bad611b 1234 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
c976d415
LH
1235 return 1;
1236
0bad611b 1237 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
c976d415
LH
1238 return 1;
1239
68db31cc 1240 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
c976d415
LH
1241 if (!lock)
1242 return error("unable to lock %s", renamed_ref);
1243 lock->force_write = 1;
678d0f4c 1244 if (write_ref_sha1(lock, orig_sha1, logmsg))
c976d415
LH
1245 return error("unable to save current sha1 in %s", renamed_ref);
1246
765c2258
PH
1247 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1248 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
c976d415
LH
1249 oldref, strerror(errno));
1250
eca35a25 1251 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
c976d415
LH
1252 error("unable to delete old %s", oldref);
1253 goto rollback;
1254 }
1255
eca35a25 1256 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
c976d415
LH
1257 if (errno==EISDIR) {
1258 if (remove_empty_directories(git_path("%s", newref))) {
1259 error("Directory not empty: %s", newref);
1260 goto rollback;
1261 }
1262 } else {
1263 error("unable to delete existing %s", newref);
1264 goto rollback;
1265 }
1266 }
1267
1268 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1269 error("unable to create directory for %s", newref);
1270 goto rollback;
1271 }
1272
1273 retry:
765c2258 1274 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
d9e74d57
JR
1275 if (errno==EISDIR || errno==ENOTDIR) {
1276 /*
1277 * rename(a, b) when b is an existing
1278 * directory ought to result in ISDIR, but
1279 * Solaris 5.8 gives ENOTDIR. Sheesh.
1280 */
c976d415
LH
1281 if (remove_empty_directories(git_path("logs/%s", newref))) {
1282 error("Directory not empty: logs/%s", newref);
1283 goto rollback;
1284 }
1285 goto retry;
1286 } else {
765c2258 1287 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
c976d415
LH
1288 newref, strerror(errno));
1289 goto rollback;
1290 }
1291 }
1292 logmoved = log;
1293
68db31cc 1294 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
c976d415
LH
1295 if (!lock) {
1296 error("unable to lock %s for update", newref);
1297 goto rollback;
1298 }
c976d415
LH
1299 lock->force_write = 1;
1300 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1301 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
c976d415
LH
1302 error("unable to write current sha1 into %s", newref);
1303 goto rollback;
1304 }
1305
1306 return 0;
1307
1308 rollback:
68db31cc 1309 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
c976d415
LH
1310 if (!lock) {
1311 error("unable to lock %s for rollback", oldref);
1312 goto rollbacklog;
1313 }
1314
1315 lock->force_write = 1;
1316 flag = log_all_ref_updates;
1317 log_all_ref_updates = 0;
1318 if (write_ref_sha1(lock, orig_sha1, NULL))
1319 error("unable to write current sha1 into %s", oldref);
1320 log_all_ref_updates = flag;
1321
1322 rollbacklog:
1323 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1324 error("unable to restore logfile %s from %s: %s",
1325 oldref, newref, strerror(errno));
1326 if (!logmoved && log &&
765c2258
PH
1327 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1328 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
c976d415
LH
1329 oldref, strerror(errno));
1330
1331 return 1;
1332}
1333
435fc852 1334int close_ref(struct ref_lock *lock)
b531394d
BC
1335{
1336 if (close_lock_file(lock->lk))
1337 return -1;
1338 lock->lock_fd = -1;
1339 return 0;
1340}
1341
435fc852 1342int commit_ref(struct ref_lock *lock)
b531394d
BC
1343{
1344 if (commit_lock_file(lock->lk))
1345 return -1;
1346 lock->lock_fd = -1;
1347 return 0;
1348}
1349
e5f38ec3 1350void unlock_ref(struct ref_lock *lock)
4bd18c43 1351{
4ed7cd3a
BC
1352 /* Do not free lock->lk -- atexit() still looks at them */
1353 if (lock->lk)
1354 rollback_lock_file(lock->lk);
434cd0cd 1355 free(lock->ref_name);
1655707c 1356 free(lock->orig_ref_name);
4bd18c43
SP
1357 free(lock);
1358}
1359
0ec29a47
JH
1360/*
1361 * copy the reflog message msg to buf, which has been allocated sufficiently
1362 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1363 * because reflog file is one line per entry.
1364 */
1365static int copy_msg(char *buf, const char *msg)
1366{
1367 char *cp = buf;
1368 char c;
1369 int wasspace = 1;
1370
1371 *cp++ = '\t';
1372 while ((c = *msg++)) {
1373 if (wasspace && isspace(c))
1374 continue;
1375 wasspace = isspace(c);
1376 if (wasspace)
1377 c = ' ';
1378 *cp++ = c;
1379 }
1380 while (buf < cp && isspace(cp[-1]))
1381 cp--;
1382 *cp++ = '\n';
1383 return cp - buf;
1384}
1385
157aaea5 1386int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
6de08ae6 1387{
859c3017 1388 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1389
157aaea5 1390 git_snpath(logfile, bufsize, "logs/%s", ref_name);
4057deb5 1391 if (log_all_ref_updates &&
cc44c765
JH
1392 (!prefixcmp(ref_name, "refs/heads/") ||
1393 !prefixcmp(ref_name, "refs/remotes/") ||
b2e256b0 1394 !prefixcmp(ref_name, "refs/notes/") ||
bd104db1 1395 !strcmp(ref_name, "HEAD"))) {
157aaea5 1396 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1397 return error("unable to create directory for %s",
157aaea5 1398 logfile);
6de08ae6
SP
1399 oflags |= O_CREAT;
1400 }
1401
157aaea5 1402 logfd = open(logfile, oflags, 0666);
6de08ae6 1403 if (logfd < 0) {
1974bf62 1404 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1405 return 0;
3b463c3f
JH
1406
1407 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1408 if (remove_empty_directories(logfile)) {
3b463c3f 1409 return error("There are still logs under '%s'",
157aaea5 1410 logfile);
3b463c3f 1411 }
157aaea5 1412 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1413 }
1414
1415 if (logfd < 0)
1416 return error("Unable to append to %s: %s",
157aaea5 1417 logfile, strerror(errno));
6de08ae6
SP
1418 }
1419
157aaea5 1420 adjust_shared_perm(logfile);
859c3017
EM
1421 close(logfd);
1422 return 0;
1423}
443b92b6 1424
859c3017
EM
1425static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1426 const unsigned char *new_sha1, const char *msg)
1427{
1428 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1429 unsigned maxlen, len;
1430 int msglen;
157aaea5 1431 char log_file[PATH_MAX];
859c3017
EM
1432 char *logrec;
1433 const char *committer;
1434
1435 if (log_all_ref_updates < 0)
1436 log_all_ref_updates = !is_bare_repository();
1437
157aaea5 1438 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
859c3017
EM
1439 if (result)
1440 return result;
1441
1442 logfd = open(log_file, oflags);
1443 if (logfd < 0)
1444 return 0;
0ec29a47 1445 msglen = msg ? strlen(msg) : 0;
774751a8 1446 committer = git_committer_info(0);
8ac65937
JH
1447 maxlen = strlen(committer) + msglen + 100;
1448 logrec = xmalloc(maxlen);
1449 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1450 sha1_to_hex(old_sha1),
1451 sha1_to_hex(new_sha1),
8ac65937
JH
1452 committer);
1453 if (msglen)
0ec29a47 1454 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1455 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1456 free(logrec);
91c8d590 1457 if (close(logfd) != 0 || written != len)
9a13f0b7 1458 return error("Unable to append to %s", log_file);
6de08ae6
SP
1459 return 0;
1460}
1461
c3b0dec5
LT
1462static int is_branch(const char *refname)
1463{
1464 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1465}
1466
4bd18c43
SP
1467int write_ref_sha1(struct ref_lock *lock,
1468 const unsigned char *sha1, const char *logmsg)
1469{
1470 static char term = '\n';
c3b0dec5 1471 struct object *o;
4bd18c43
SP
1472
1473 if (!lock)
95fc7512 1474 return -1;
a89fccd2 1475 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1476 unlock_ref(lock);
1477 return 0;
95fc7512 1478 }
c3b0dec5
LT
1479 o = parse_object(sha1);
1480 if (!o) {
7be8b3ba 1481 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
1482 lock->ref_name, sha1_to_hex(sha1));
1483 unlock_ref(lock);
1484 return -1;
1485 }
1486 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1487 error("Trying to write non-commit object %s to branch %s",
1488 sha1_to_hex(sha1), lock->ref_name);
1489 unlock_ref(lock);
1490 return -1;
1491 }
93822c22
AW
1492 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1493 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1494 || close_ref(lock) < 0) {
c33d5174 1495 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1496 unlock_ref(lock);
1497 return -1;
1498 }
5e290ff7 1499 invalidate_cached_refs();
bd104db1
NP
1500 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1501 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1502 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1503 unlock_ref(lock);
1504 return -1;
1505 }
605fac8b
NP
1506 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1507 /*
1508 * Special hack: If a branch is updated directly and HEAD
1509 * points to it (may happen on the remote side of a push
1510 * for example) then logically the HEAD reflog should be
1511 * updated too.
1512 * A generic solution implies reverse symref information,
1513 * but finding all symrefs pointing to the given branch
1514 * would be rather costly for this rare event (the direct
1515 * update of a branch) to be worth it. So let's cheat and
1516 * check with HEAD only which should cover 99% of all usage
1517 * scenarios (even 100% of the default ones).
1518 */
1519 unsigned char head_sha1[20];
1520 int head_flag;
1521 const char *head_ref;
1522 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1523 if (head_ref && (head_flag & REF_ISSYMREF) &&
1524 !strcmp(head_ref, lock->ref_name))
1525 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1526 }
b531394d 1527 if (commit_ref(lock)) {
434cd0cd 1528 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1529 unlock_ref(lock);
1530 return -1;
1531 }
4bd18c43
SP
1532 unlock_ref(lock);
1533 return 0;
95fc7512 1534}
d556fae2 1535
8b5157e4
NP
1536int create_symref(const char *ref_target, const char *refs_heads_master,
1537 const char *logmsg)
41b625b0
NP
1538{
1539 const char *lockpath;
1540 char ref[1000];
1541 int fd, len, written;
a4f34cbb 1542 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1543 unsigned char old_sha1[20], new_sha1[20];
1544
1545 if (logmsg && read_ref(ref_target, old_sha1))
1546 hashclr(old_sha1);
41b625b0 1547
d48744d1
JH
1548 if (safe_create_leading_directories(git_HEAD) < 0)
1549 return error("unable to create directory for %s", git_HEAD);
1550
41b625b0
NP
1551#ifndef NO_SYMLINK_HEAD
1552 if (prefer_symlink_refs) {
1553 unlink(git_HEAD);
1554 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1555 goto done;
41b625b0
NP
1556 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1557 }
1558#endif
1559
1560 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1561 if (sizeof(ref) <= len) {
1562 error("refname too long: %s", refs_heads_master);
47fc52e2 1563 goto error_free_return;
41b625b0
NP
1564 }
1565 lockpath = mkpath("%s.lock", git_HEAD);
1566 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1567 if (fd < 0) {
1568 error("Unable to open %s for writing", lockpath);
47fc52e2 1569 goto error_free_return;
41b625b0
NP
1570 }
1571 written = write_in_full(fd, ref, len);
91c8d590 1572 if (close(fd) != 0 || written != len) {
41b625b0 1573 error("Unable to write to %s", lockpath);
47fc52e2 1574 goto error_unlink_return;
41b625b0
NP
1575 }
1576 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1577 error("Unable to create %s", git_HEAD);
47fc52e2 1578 goto error_unlink_return;
41b625b0
NP
1579 }
1580 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1581 error("Unable to fix permissions on %s", lockpath);
47fc52e2 1582 error_unlink_return:
691f1a28 1583 unlink_or_warn(lockpath);
47fc52e2
JH
1584 error_free_return:
1585 free(git_HEAD);
1586 return -1;
41b625b0 1587 }
8b5157e4 1588
ee96d11b 1589#ifndef NO_SYMLINK_HEAD
8b5157e4 1590 done:
ee96d11b 1591#endif
8b5157e4
NP
1592 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1593 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1594
47fc52e2 1595 free(git_HEAD);
41b625b0
NP
1596 return 0;
1597}
1598
16d7cc90
JH
1599static char *ref_msg(const char *line, const char *endp)
1600{
1601 const char *ep;
16d7cc90 1602 line += 82;
182af834
PH
1603 ep = memchr(line, '\n', endp - line);
1604 if (!ep)
1605 ep = endp;
1606 return xmemdupz(line, ep - line);
16d7cc90
JH
1607}
1608
1609int 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 1610{
e5229042 1611 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1612 char *tz_c;
e29cb53a 1613 int logfd, tz, reccnt = 0;
d556fae2
SP
1614 struct stat st;
1615 unsigned long date;
e5229042 1616 unsigned char logged_sha1[20];
cb48cb58 1617 void *log_mapped;
dc49cd76 1618 size_t mapsz;
d556fae2
SP
1619
1620 logfile = git_path("logs/%s", ref);
1621 logfd = open(logfile, O_RDONLY, 0);
1622 if (logfd < 0)
d824cbba 1623 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
1624 fstat(logfd, &st);
1625 if (!st.st_size)
1626 die("Log %s is empty.", logfile);
dc49cd76
SP
1627 mapsz = xsize_t(st.st_size);
1628 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1629 logdata = log_mapped;
d556fae2
SP
1630 close(logfd);
1631
e5229042 1632 lastrec = NULL;
d556fae2
SP
1633 rec = logend = logdata + st.st_size;
1634 while (logdata < rec) {
e29cb53a 1635 reccnt++;
d556fae2
SP
1636 if (logdata < rec && *(rec-1) == '\n')
1637 rec--;
e5229042
SP
1638 lastgt = NULL;
1639 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1640 rec--;
e5229042
SP
1641 if (*rec == '>')
1642 lastgt = rec;
1643 }
1644 if (!lastgt)
d556fae2 1645 die("Log %s is corrupt.", logfile);
e5229042 1646 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1647 if (date <= at_time || cnt == 0) {
76a44c5c 1648 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1649 if (msg)
1650 *msg = ref_msg(rec, logend);
1651 if (cutoff_time)
1652 *cutoff_time = date;
1653 if (cutoff_tz)
1654 *cutoff_tz = tz;
1655 if (cutoff_cnt)
76a44c5c 1656 *cutoff_cnt = reccnt - 1;
e5229042
SP
1657 if (lastrec) {
1658 if (get_sha1_hex(lastrec, logged_sha1))
1659 die("Log %s is corrupt.", logfile);
1660 if (get_sha1_hex(rec + 41, sha1))
1661 die("Log %s is corrupt.", logfile);
a89fccd2 1662 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1663 warning("Log %s has gap after %s.",
73013afd 1664 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1665 }
e5f38ec3
JH
1666 }
1667 else if (date == at_time) {
e5229042
SP
1668 if (get_sha1_hex(rec + 41, sha1))
1669 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1670 }
1671 else {
e5229042
SP
1672 if (get_sha1_hex(rec + 41, logged_sha1))
1673 die("Log %s is corrupt.", logfile);
a89fccd2 1674 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1675 warning("Log %s unexpectedly ended on %s.",
73013afd 1676 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1677 }
1678 }
dc49cd76 1679 munmap(log_mapped, mapsz);
d556fae2
SP
1680 return 0;
1681 }
e5229042 1682 lastrec = rec;
ab2a1a32
JH
1683 if (cnt > 0)
1684 cnt--;
d556fae2
SP
1685 }
1686
e5229042
SP
1687 rec = logdata;
1688 while (rec < logend && *rec != '>' && *rec != '\n')
1689 rec++;
1690 if (rec == logend || *rec == '\n')
d556fae2 1691 die("Log %s is corrupt.", logfile);
e5229042 1692 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1693 tz = strtoul(tz_c, NULL, 10);
1694 if (get_sha1_hex(logdata, sha1))
1695 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1696 if (is_null_sha1(sha1)) {
1697 if (get_sha1_hex(logdata + 41, sha1))
1698 die("Log %s is corrupt.", logfile);
1699 }
16d7cc90
JH
1700 if (msg)
1701 *msg = ref_msg(logdata, logend);
dc49cd76 1702 munmap(log_mapped, mapsz);
16d7cc90
JH
1703
1704 if (cutoff_time)
1705 *cutoff_time = date;
1706 if (cutoff_tz)
1707 *cutoff_tz = tz;
1708 if (cutoff_cnt)
1709 *cutoff_cnt = reccnt;
1710 return 1;
d556fae2 1711}
2ff81662 1712
101d15e0 1713int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
1714{
1715 const char *logfile;
1716 FILE *logfp;
8ca78803 1717 struct strbuf sb = STRBUF_INIT;
2266bf27 1718 int ret = 0;
2ff81662
JH
1719
1720 logfile = git_path("logs/%s", ref);
1721 logfp = fopen(logfile, "r");
1722 if (!logfp)
883d60fa 1723 return -1;
101d15e0
JH
1724
1725 if (ofs) {
1726 struct stat statbuf;
1727 if (fstat(fileno(logfp), &statbuf) ||
1728 statbuf.st_size < ofs ||
1729 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 1730 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 1731 fclose(logfp);
8ca78803 1732 strbuf_release(&sb);
101d15e0 1733 return -1;
9d33f7c2 1734 }
101d15e0
JH
1735 }
1736
8ca78803 1737 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 1738 unsigned char osha1[20], nsha1[20];
883d60fa
JS
1739 char *email_end, *message;
1740 unsigned long timestamp;
8ca78803 1741 int tz;
2ff81662
JH
1742
1743 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
1744 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1745 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1746 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1747 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
1748 email_end[1] != ' ' ||
1749 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1750 !message || message[0] != ' ' ||
1751 (message[1] != '+' && message[1] != '-') ||
1752 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 1753 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 1754 continue; /* corrupt? */
883d60fa
JS
1755 email_end[1] = '\0';
1756 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
1757 if (message[6] != '\t')
1758 message += 6;
1759 else
1760 message += 7;
8ca78803
RS
1761 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1762 cb_data);
883d60fa 1763 if (ret)
2266bf27 1764 break;
2ff81662
JH
1765 }
1766 fclose(logfp);
8ca78803 1767 strbuf_release(&sb);
2266bf27 1768 return ret;
2ff81662 1769}
e29cb53a 1770
101d15e0
JH
1771int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1772{
1773 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1774}
1775
eb8381c8
NP
1776static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1777{
1778 DIR *dir = opendir(git_path("logs/%s", base));
fcee5a14 1779 int retval = 0;
eb8381c8
NP
1780
1781 if (dir) {
1782 struct dirent *de;
1783 int baselen = strlen(base);
1784 char *log = xmalloc(baselen + 257);
1785
1786 memcpy(log, base, baselen);
1787 if (baselen && base[baselen-1] != '/')
1788 log[baselen++] = '/';
1789
1790 while ((de = readdir(dir)) != NULL) {
1791 struct stat st;
1792 int namelen;
1793
1794 if (de->d_name[0] == '.')
1795 continue;
1796 namelen = strlen(de->d_name);
1797 if (namelen > 255)
1798 continue;
1799 if (has_extension(de->d_name, ".lock"))
1800 continue;
1801 memcpy(log + baselen, de->d_name, namelen+1);
1802 if (stat(git_path("logs/%s", log), &st) < 0)
1803 continue;
1804 if (S_ISDIR(st.st_mode)) {
1805 retval = do_for_each_reflog(log, fn, cb_data);
1806 } else {
1807 unsigned char sha1[20];
1808 if (!resolve_ref(log, sha1, 0, NULL))
1809 retval = error("bad ref for %s", log);
1810 else
1811 retval = fn(log, sha1, 0, cb_data);
1812 }
1813 if (retval)
1814 break;
1815 }
1816 free(log);
1817 closedir(dir);
1818 }
acb39f64 1819 else if (*base)
fcee5a14 1820 return errno;
eb8381c8
NP
1821 return retval;
1822}
1823
1824int for_each_reflog(each_ref_fn fn, void *cb_data)
1825{
1826 return do_for_each_reflog("", fn, cb_data);
1827}
3d9f037c
CR
1828
1829int update_ref(const char *action, const char *refname,
1830 const unsigned char *sha1, const unsigned char *oldval,
1831 int flags, enum action_on_err onerr)
1832{
1833 static struct ref_lock *lock;
1834 lock = lock_any_ref_for_update(refname, oldval, flags);
1835 if (!lock) {
1836 const char *str = "Cannot lock the ref '%s'.";
1837 switch (onerr) {
1838 case MSG_ON_ERR: error(str, refname); break;
1839 case DIE_ON_ERR: die(str, refname); break;
1840 case QUIET_ON_ERR: break;
1841 }
1842 return 1;
1843 }
1844 if (write_ref_sha1(lock, sha1, action) < 0) {
1845 const char *str = "Cannot update the ref '%s'.";
1846 switch (onerr) {
1847 case MSG_ON_ERR: error(str, refname); break;
1848 case DIE_ON_ERR: die(str, refname); break;
1849 case QUIET_ON_ERR: break;
1850 }
1851 return 1;
1852 }
1853 return 0;
1854}
cda69f48 1855
c17b2294
JH
1856int ref_exists(char *refname)
1857{
1858 unsigned char sha1[20];
1859 return !!resolve_ref(refname, sha1, 1, NULL);
1860}
1861
5483f799 1862struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
1863{
1864 for ( ; list; list = list->next)
1865 if (!strcmp(list->name, name))
5483f799 1866 return (struct ref *)list;
cda69f48
JK
1867 return NULL;
1868}
7c2b3029
JK
1869
1870/*
1871 * generate a format suitable for scanf from a ref_rev_parse_rules
1872 * rule, that is replace the "%.*s" spec with a "%s" spec
1873 */
1874static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1875{
1876 char *spec;
1877
1878 spec = strstr(rule, "%.*s");
1879 if (!spec || strstr(spec + 4, "%.*s"))
1880 die("invalid rule in ref_rev_parse_rules: %s", rule);
1881
1882 /* copy all until spec */
1883 strncpy(scanf_fmt, rule, spec - rule);
1884 scanf_fmt[spec - rule] = '\0';
1885 /* copy new spec */
1886 strcat(scanf_fmt, "%s");
1887 /* copy remaining rule */
1888 strcat(scanf_fmt, spec + 4);
1889
1890 return;
1891}
1892
6e7b3309 1893char *shorten_unambiguous_ref(const char *ref, int strict)
7c2b3029
JK
1894{
1895 int i;
1896 static char **scanf_fmts;
1897 static int nr_rules;
1898 char *short_name;
1899
1900 /* pre generate scanf formats from ref_rev_parse_rules[] */
1901 if (!nr_rules) {
1902 size_t total_len = 0;
1903
1904 /* the rule list is NULL terminated, count them first */
1905 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1906 /* no +1 because strlen("%s") < strlen("%.*s") */
1907 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1908
1909 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1910
1911 total_len = 0;
1912 for (i = 0; i < nr_rules; i++) {
1913 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1914 + total_len;
1915 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1916 total_len += strlen(ref_rev_parse_rules[i]);
1917 }
1918 }
1919
1920 /* bail out if there are no rules */
1921 if (!nr_rules)
1922 return xstrdup(ref);
1923
1924 /* buffer for scanf result, at most ref must fit */
1925 short_name = xstrdup(ref);
1926
1927 /* skip first rule, it will always match */
1928 for (i = nr_rules - 1; i > 0 ; --i) {
1929 int j;
6e7b3309 1930 int rules_to_fail = i;
7c2b3029
JK
1931 int short_name_len;
1932
1933 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1934 continue;
1935
1936 short_name_len = strlen(short_name);
1937
6e7b3309
BW
1938 /*
1939 * in strict mode, all (except the matched one) rules
1940 * must fail to resolve to a valid non-ambiguous ref
1941 */
1942 if (strict)
1943 rules_to_fail = nr_rules;
1944
7c2b3029
JK
1945 /*
1946 * check if the short name resolves to a valid ref,
1947 * but use only rules prior to the matched one
1948 */
6e7b3309 1949 for (j = 0; j < rules_to_fail; j++) {
7c2b3029
JK
1950 const char *rule = ref_rev_parse_rules[j];
1951 unsigned char short_objectname[20];
1952 char refname[PATH_MAX];
1953
6e7b3309
BW
1954 /* skip matched rule */
1955 if (i == j)
1956 continue;
1957
7c2b3029
JK
1958 /*
1959 * the short name is ambiguous, if it resolves
1960 * (with this previous rule) to a valid ref
1961 * read_ref() returns 0 on success
1962 */
1963 mksnpath(refname, sizeof(refname),
1964 rule, short_name_len, short_name);
1965 if (!read_ref(refname, short_objectname))
1966 break;
1967 }
1968
1969 /*
1970 * short name is non-ambiguous if all previous rules
1971 * haven't resolved to a valid ref
1972 */
6e7b3309 1973 if (j == rules_to_fail)
7c2b3029
JK
1974 return short_name;
1975 }
1976
1977 free(short_name);
1978 return xstrdup(ref);
1979}