gitignore git-bisect--helper
[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
9
e1e22e37
LT
10struct ref_list {
11 struct ref_list *next;
f4204ab9 12 unsigned char flag; /* ISSYMREF? ISPACKED? */
e1e22e37 13 unsigned char sha1[20];
f4204ab9 14 unsigned char peeled[20];
e1e22e37
LT
15 char name[FLEX_ARRAY];
16};
17
f4204ab9 18static const char *parse_ref_line(char *line, unsigned char *sha1)
e1e22e37
LT
19{
20 /*
21 * 42: the answer to everything.
22 *
23 * In this case, it happens to be the answer to
24 * 40 (length of sha1 hex representation)
25 * +1 (space in between hex and name)
26 * +1 (newline at the end of the line)
27 */
28 int len = strlen(line) - 42;
29
30 if (len <= 0)
31 return NULL;
32 if (get_sha1_hex(line, sha1) < 0)
33 return NULL;
34 if (!isspace(line[40]))
35 return NULL;
36 line += 41;
f4204ab9
JH
37 if (isspace(*line))
38 return NULL;
e1e22e37
LT
39 if (line[len] != '\n')
40 return NULL;
41 line[len] = 0;
cf0adba7 42
e1e22e37
LT
43 return line;
44}
45
8da19775 46static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
f4204ab9
JH
47 int flag, struct ref_list *list,
48 struct ref_list **new_entry)
e1e22e37
LT
49{
50 int len;
c774aab9 51 struct ref_list *entry;
e1e22e37
LT
52
53 /* Allocate it and add it in.. */
54 len = strlen(name) + 1;
55 entry = xmalloc(sizeof(struct ref_list) + len);
56 hashcpy(entry->sha1, sha1);
f4204ab9 57 hashclr(entry->peeled);
e1e22e37 58 memcpy(entry->name, name, len);
8da19775 59 entry->flag = flag;
c774aab9 60 entry->next = list;
f4204ab9
JH
61 if (new_entry)
62 *new_entry = entry;
c774aab9
JP
63 return entry;
64}
65
66/* merge sort the ref list */
67static struct ref_list *sort_ref_list(struct ref_list *list)
68{
69 int psize, qsize, last_merge_count, cmp;
70 struct ref_list *p, *q, *l, *e;
71 struct ref_list *new_list = list;
72 int k = 1;
73 int merge_count = 0;
74
75 if (!list)
76 return list;
77
78 do {
79 last_merge_count = merge_count;
80 merge_count = 0;
81
82 psize = 0;
83
84 p = new_list;
85 q = new_list;
86 new_list = NULL;
87 l = NULL;
88
89 while (p) {
90 merge_count++;
91
92 while (psize < k && q->next) {
93 q = q->next;
94 psize++;
95 }
96 qsize = k;
97
98 while ((psize > 0) || (qsize > 0 && q)) {
99 if (qsize == 0 || !q) {
100 e = p;
101 p = p->next;
102 psize--;
103 } else if (psize == 0) {
104 e = q;
105 q = q->next;
106 qsize--;
107 } else {
108 cmp = strcmp(q->name, p->name);
109 if (cmp < 0) {
110 e = q;
111 q = q->next;
112 qsize--;
113 } else if (cmp > 0) {
114 e = p;
115 p = p->next;
116 psize--;
117 } else {
118 if (hashcmp(q->sha1, p->sha1))
119 die("Duplicated ref, and SHA1s don't match: %s",
120 q->name);
121 warning("Duplicated ref: %s", q->name);
122 e = q;
123 q = q->next;
124 qsize--;
125 free(e);
126 e = p;
127 p = p->next;
128 psize--;
129 }
130 }
131
132 e->next = NULL;
133
134 if (l)
135 l->next = e;
136 if (!new_list)
137 new_list = e;
138 l = e;
139 }
140
141 p = q;
142 };
143
144 k = k * 2;
145 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
146
147 return new_list;
e1e22e37
LT
148}
149
5e290ff7
JH
150/*
151 * Future: need to be in "struct repository"
152 * when doing a full libification.
153 */
4175e9e3 154static struct cached_refs {
5e290ff7
JH
155 char did_loose;
156 char did_packed;
157 struct ref_list *loose;
158 struct ref_list *packed;
159} cached_refs;
0ae91be0 160static struct ref_list *current_ref;
5e290ff7 161
e142a3c6
DB
162static struct ref_list *extra_refs;
163
5e290ff7
JH
164static void free_ref_list(struct ref_list *list)
165{
166 struct ref_list *next;
167 for ( ; list; list = next) {
168 next = list->next;
169 free(list);
170 }
171}
172
173static void invalidate_cached_refs(void)
e1e22e37 174{
5e290ff7
JH
175 struct cached_refs *ca = &cached_refs;
176
177 if (ca->did_loose && ca->loose)
178 free_ref_list(ca->loose);
179 if (ca->did_packed && ca->packed)
180 free_ref_list(ca->packed);
181 ca->loose = ca->packed = NULL;
182 ca->did_loose = ca->did_packed = 0;
183}
e1e22e37 184
f4204ab9
JH
185static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
186{
187 struct ref_list *list = NULL;
188 struct ref_list *last = NULL;
189 char refline[PATH_MAX];
190 int flag = REF_ISPACKED;
191
192 while (fgets(refline, sizeof(refline), f)) {
193 unsigned char sha1[20];
194 const char *name;
195 static const char header[] = "# pack-refs with:";
196
197 if (!strncmp(refline, header, sizeof(header)-1)) {
198 const char *traits = refline + sizeof(header) - 1;
199 if (strstr(traits, " peeled "))
200 flag |= REF_KNOWS_PEELED;
201 /* perhaps other traits later as well */
202 continue;
203 }
204
205 name = parse_ref_line(refline, sha1);
206 if (name) {
207 list = add_ref(name, sha1, flag, list, &last);
208 continue;
209 }
210 if (last &&
211 refline[0] == '^' &&
212 strlen(refline) == 42 &&
213 refline[41] == '\n' &&
214 !get_sha1_hex(refline + 1, sha1))
215 hashcpy(last->peeled, sha1);
216 }
c774aab9 217 cached_refs->packed = sort_ref_list(list);
f4204ab9
JH
218}
219
e142a3c6
DB
220void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
221{
222 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
223}
224
225void clear_extra_refs(void)
226{
227 free_ref_list(extra_refs);
228 extra_refs = NULL;
229}
230
5e290ff7
JH
231static struct ref_list *get_packed_refs(void)
232{
233 if (!cached_refs.did_packed) {
e1e22e37 234 FILE *f = fopen(git_path("packed-refs"), "r");
f4204ab9 235 cached_refs.packed = NULL;
e1e22e37 236 if (f) {
f4204ab9 237 read_packed_refs(f, &cached_refs);
e1e22e37 238 fclose(f);
e1e22e37 239 }
5e290ff7 240 cached_refs.did_packed = 1;
e1e22e37 241 }
5e290ff7 242 return cached_refs.packed;
e1e22e37
LT
243}
244
245static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
246{
247 DIR *dir = opendir(git_path("%s", base));
248
249 if (dir) {
250 struct dirent *de;
251 int baselen = strlen(base);
ed378ec7 252 char *ref = xmalloc(baselen + 257);
e1e22e37 253
ed378ec7 254 memcpy(ref, base, baselen);
e1e22e37 255 if (baselen && base[baselen-1] != '/')
ed378ec7 256 ref[baselen++] = '/';
e1e22e37
LT
257
258 while ((de = readdir(dir)) != NULL) {
259 unsigned char sha1[20];
260 struct stat st;
8da19775 261 int flag;
e1e22e37
LT
262 int namelen;
263
264 if (de->d_name[0] == '.')
265 continue;
266 namelen = strlen(de->d_name);
267 if (namelen > 255)
268 continue;
269 if (has_extension(de->d_name, ".lock"))
270 continue;
ed378ec7
LT
271 memcpy(ref + baselen, de->d_name, namelen+1);
272 if (stat(git_path("%s", ref), &st) < 0)
e1e22e37
LT
273 continue;
274 if (S_ISDIR(st.st_mode)) {
ed378ec7 275 list = get_ref_dir(ref, list);
e1e22e37
LT
276 continue;
277 }
f8948e2f
JH
278 if (!resolve_ref(ref, sha1, 1, &flag))
279 hashclr(sha1);
f4204ab9 280 list = add_ref(ref, sha1, flag, list, NULL);
e1e22e37 281 }
ed378ec7 282 free(ref);
e1e22e37
LT
283 closedir(dir);
284 }
c774aab9 285 return sort_ref_list(list);
e1e22e37
LT
286}
287
f8948e2f
JH
288struct warn_if_dangling_data {
289 const char *refname;
290 const char *msg_fmt;
291};
292
293static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
294 int flags, void *cb_data)
295{
296 struct warn_if_dangling_data *d = cb_data;
297 const char *resolves_to;
298 unsigned char junk[20];
299
300 if (!(flags & REF_ISSYMREF))
301 return 0;
302
303 resolves_to = resolve_ref(refname, junk, 0, NULL);
304 if (!resolves_to || strcmp(resolves_to, d->refname))
305 return 0;
306
307 printf(d->msg_fmt, refname);
308 return 0;
309}
310
311void warn_dangling_symref(const char *msg_fmt, const char *refname)
312{
313 struct warn_if_dangling_data data = { refname, msg_fmt };
314 for_each_rawref(warn_if_dangling_symref, &data);
315}
316
e1e22e37
LT
317static struct ref_list *get_loose_refs(void)
318{
5e290ff7
JH
319 if (!cached_refs.did_loose) {
320 cached_refs.loose = get_ref_dir("refs", NULL);
321 cached_refs.did_loose = 1;
e1e22e37 322 }
5e290ff7 323 return cached_refs.loose;
e1e22e37
LT
324}
325
ca8db142
LT
326/* We allow "recursive" symbolic refs. Only within reason, though */
327#define MAXDEPTH 5
0ebde32c
LT
328#define MAXREFLEN (1024)
329
330static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
331{
332 FILE *f;
333 struct cached_refs refs;
334 struct ref_list *ref;
335 int retval;
336
337 strcpy(name + pathlen, "packed-refs");
338 f = fopen(name, "r");
339 if (!f)
340 return -1;
341 read_packed_refs(f, &refs);
342 fclose(f);
343 ref = refs.packed;
344 retval = -1;
345 while (ref) {
346 if (!strcmp(ref->name, refname)) {
347 retval = 0;
348 memcpy(result, ref->sha1, 20);
349 break;
350 }
351 ref = ref->next;
352 }
353 free_ref_list(refs.packed);
354 return retval;
355}
356
357static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
358{
359 int fd, len = strlen(refname);
360 char buffer[128], *p;
361
362 if (recursion > MAXDEPTH || len > MAXREFLEN)
363 return -1;
364 memcpy(name + pathlen, refname, len+1);
365 fd = open(name, O_RDONLY);
366 if (fd < 0)
367 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
368
369 len = read(fd, buffer, sizeof(buffer)-1);
370 close(fd);
371 if (len < 0)
372 return -1;
373 while (len && isspace(buffer[len-1]))
374 len--;
375 buffer[len] = 0;
376
377 /* Was it a detached head or an old-fashioned symlink? */
378 if (!get_sha1_hex(buffer, result))
379 return 0;
380
381 /* Symref? */
382 if (strncmp(buffer, "ref:", 4))
383 return -1;
384 p = buffer + 4;
385 while (isspace(*p))
386 p++;
387
388 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
389}
390
391int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
392{
393 int len = strlen(path), retval;
394 char *gitdir;
842abf06 395 const char *tmp;
0ebde32c
LT
396
397 while (len && path[len-1] == '/')
398 len--;
399 if (!len)
400 return -1;
401 gitdir = xmalloc(len + MAXREFLEN + 8);
402 memcpy(gitdir, path, len);
842abf06
LH
403 memcpy(gitdir + len, "/.git", 6);
404 len += 5;
405
406 tmp = read_gitfile_gently(gitdir);
407 if (tmp) {
408 free(gitdir);
409 len = strlen(tmp);
410 gitdir = xmalloc(len + MAXREFLEN + 3);
411 memcpy(gitdir, tmp, len);
412 }
413 gitdir[len] = '/';
414 gitdir[++len] = '\0';
415 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
0ebde32c
LT
416 free(gitdir);
417 return retval;
418}
ca8db142 419
4886b89f
CC
420/*
421 * If the "reading" argument is set, this function finds out what _object_
422 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
423 * has to exist, and if it is symbolic, it has to point at an existing ref,
424 * because the "read" goes through the symref to the ref it points at.
425 *
426 * The access that is not "reading" may often be "writing", but does not
427 * have to; it can be merely checking _where it leads to_. If it is a
428 * prelude to "writing" to the ref, a write to a symref that points at
429 * yet-to-be-born ref will create the real ref pointed by the symref.
430 * reading=0 allows the caller to check where such a symref leads to.
431 */
8da19775 432const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
8a65ff76 433{
0104ca09
HO
434 int depth = MAXDEPTH;
435 ssize_t len;
a876ed83 436 char buffer[256];
ed378ec7 437 static char ref_buffer[256];
ca8db142 438
8da19775
JH
439 if (flag)
440 *flag = 0;
441
a876ed83 442 for (;;) {
958a4789 443 char path[PATH_MAX];
a876ed83
JH
444 struct stat st;
445 char *buf;
446 int fd;
8a65ff76 447
a876ed83
JH
448 if (--depth < 0)
449 return NULL;
ca8db142 450
958a4789 451 git_snpath(path, sizeof(path), "%s", ref);
4886b89f 452 /* Special case: non-existing file. */
a876ed83 453 if (lstat(path, &st) < 0) {
434cd0cd
LT
454 struct ref_list *list = get_packed_refs();
455 while (list) {
f4204ab9 456 if (!strcmp(ref, list->name)) {
434cd0cd 457 hashcpy(sha1, list->sha1);
8da19775
JH
458 if (flag)
459 *flag |= REF_ISPACKED;
434cd0cd
LT
460 return ref;
461 }
462 list = list->next;
463 }
a876ed83
JH
464 if (reading || errno != ENOENT)
465 return NULL;
e702496e 466 hashclr(sha1);
ed378ec7 467 return ref;
a876ed83 468 }
ca8db142 469
a876ed83
JH
470 /* Follow "normalized" - ie "refs/.." symlinks by hand */
471 if (S_ISLNK(st.st_mode)) {
472 len = readlink(path, buffer, sizeof(buffer)-1);
473 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
ed378ec7
LT
474 buffer[len] = 0;
475 strcpy(ref_buffer, buffer);
476 ref = ref_buffer;
8da19775
JH
477 if (flag)
478 *flag |= REF_ISSYMREF;
a876ed83
JH
479 continue;
480 }
ca8db142 481 }
a876ed83 482
7a21632f
DS
483 /* Is it a directory? */
484 if (S_ISDIR(st.st_mode)) {
485 errno = EISDIR;
486 return NULL;
487 }
488
a876ed83
JH
489 /*
490 * Anything else, just open it and try to use it as
491 * a ref
492 */
493 fd = open(path, O_RDONLY);
494 if (fd < 0)
495 return NULL;
93d26e4c 496 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83
JH
497 close(fd);
498
499 /*
500 * Is it a symbolic ref?
501 */
502 if (len < 4 || memcmp("ref:", buffer, 4))
503 break;
504 buf = buffer + 4;
505 len -= 4;
506 while (len && isspace(*buf))
507 buf++, len--;
508 while (len && isspace(buf[len-1]))
ed378ec7
LT
509 len--;
510 buf[len] = 0;
511 memcpy(ref_buffer, buf, len + 1);
512 ref = ref_buffer;
8da19775
JH
513 if (flag)
514 *flag |= REF_ISSYMREF;
8a65ff76 515 }
a876ed83
JH
516 if (len < 40 || get_sha1_hex(buffer, sha1))
517 return NULL;
ed378ec7 518 return ref;
a876ed83
JH
519}
520
ed378ec7 521int read_ref(const char *ref, unsigned char *sha1)
a876ed83 522{
8da19775 523 if (resolve_ref(ref, sha1, 1, NULL))
a876ed83
JH
524 return 0;
525 return -1;
8a65ff76
LT
526}
527
f8948e2f 528#define DO_FOR_EACH_INCLUDE_BROKEN 01
ef06b918 529static int do_one_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 530 int flags, void *cb_data, struct ref_list *entry)
ef06b918
JH
531{
532 if (strncmp(base, entry->name, trim))
533 return 0;
f8948e2f
JH
534 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
535 if (is_null_sha1(entry->sha1))
536 return 0;
537 if (!has_sha1_file(entry->sha1)) {
538 error("%s does not point to a valid object!", entry->name);
539 return 0;
540 }
ef06b918 541 }
0ae91be0 542 current_ref = entry;
ef06b918
JH
543 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
544}
545
cf0adba7
JH
546int peel_ref(const char *ref, unsigned char *sha1)
547{
548 int flag;
549 unsigned char base[20];
550 struct object *o;
551
0ae91be0
SP
552 if (current_ref && (current_ref->name == ref
553 || !strcmp(current_ref->name, ref))) {
554 if (current_ref->flag & REF_KNOWS_PEELED) {
555 hashcpy(sha1, current_ref->peeled);
556 return 0;
557 }
558 hashcpy(base, current_ref->sha1);
559 goto fallback;
560 }
561
cf0adba7
JH
562 if (!resolve_ref(ref, base, 1, &flag))
563 return -1;
564
565 if ((flag & REF_ISPACKED)) {
566 struct ref_list *list = get_packed_refs();
cf0adba7
JH
567
568 while (list) {
f4204ab9
JH
569 if (!strcmp(list->name, ref)) {
570 if (list->flag & REF_KNOWS_PEELED) {
571 hashcpy(sha1, list->peeled);
572 return 0;
573 }
574 /* older pack-refs did not leave peeled ones */
575 break;
cf0adba7
JH
576 }
577 list = list->next;
578 }
cf0adba7
JH
579 }
580
0ae91be0 581fallback:
cf0adba7 582 o = parse_object(base);
8c87dc77 583 if (o && o->type == OBJ_TAG) {
cf0adba7
JH
584 o = deref_tag(o, ref, 0);
585 if (o) {
586 hashcpy(sha1, o->sha1);
587 return 0;
588 }
589 }
590 return -1;
591}
592
8da19775 593static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 594 int flags, void *cb_data)
8a65ff76 595{
0ae91be0 596 int retval = 0;
e1e22e37
LT
597 struct ref_list *packed = get_packed_refs();
598 struct ref_list *loose = get_loose_refs();
8a65ff76 599
e142a3c6
DB
600 struct ref_list *extra;
601
602 for (extra = extra_refs; extra; extra = extra->next)
f8948e2f 603 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
e142a3c6 604
e1e22e37
LT
605 while (packed && loose) {
606 struct ref_list *entry;
607 int cmp = strcmp(packed->name, loose->name);
608 if (!cmp) {
609 packed = packed->next;
610 continue;
6cada6a9 611 }
e1e22e37
LT
612 if (cmp > 0) {
613 entry = loose;
614 loose = loose->next;
615 } else {
616 entry = packed;
617 packed = packed->next;
618 }
f8948e2f 619 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
e1e22e37 620 if (retval)
0ae91be0 621 goto end_each;
e1e22e37 622 }
8a65ff76 623
ef06b918 624 for (packed = packed ? packed : loose; packed; packed = packed->next) {
f8948e2f 625 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
ef06b918 626 if (retval)
0ae91be0 627 goto end_each;
8a65ff76 628 }
0ae91be0
SP
629
630end_each:
631 current_ref = NULL;
632 return retval;
8a65ff76
LT
633}
634
cb5d709f 635int head_ref(each_ref_fn fn, void *cb_data)
723c31fe
LT
636{
637 unsigned char sha1[20];
8da19775
JH
638 int flag;
639
640 if (resolve_ref("HEAD", sha1, 1, &flag))
641 return fn("HEAD", sha1, flag, cb_data);
2f34ba32 642 return 0;
723c31fe
LT
643}
644
cb5d709f 645int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 646{
f8948e2f 647 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
a62be77f
SE
648}
649
2a8177b6
CC
650int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
651{
652 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
653}
654
cb5d709f 655int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 656{
2a8177b6 657 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
658}
659
cb5d709f 660int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 661{
2a8177b6 662 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
663}
664
cb5d709f 665int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 666{
2a8177b6 667 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
668}
669
670int for_each_rawref(each_ref_fn fn, void *cb_data)
671{
672 return do_for_each_ref("refs/", fn, 0,
673 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
674}
675
03feddd6
JH
676/*
677 * Make sure "ref" is something reasonable to have under ".git/refs/";
678 * We do not like it if:
679 *
680 * - any path component of it begins with ".", or
681 * - it has double dots "..", or
682 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
683 * - it ends with a "/".
3e262b95 684 * - it ends with ".lock"
03feddd6
JH
685 */
686
687static inline int bad_ref_char(int ch)
688{
8558fd9e
DB
689 if (((unsigned) ch) <= ' ' ||
690 ch == '~' || ch == '^' || ch == ':')
691 return 1;
692 /* 2.13 Pattern Matching Notation */
693 if (ch == '?' || ch == '[') /* Unsupported */
694 return 1;
695 if (ch == '*') /* Supported at the end */
696 return 2;
697 return 0;
03feddd6
JH
698}
699
95fc7512
DB
700int check_ref_format(const char *ref)
701{
cbdffe40 702 int ch, level, bad_type, last;
abd2bde7 703 int ret = CHECK_REF_FORMAT_OK;
03feddd6
JH
704 const char *cp = ref;
705
706 level = 0;
707 while (1) {
708 while ((ch = *cp++) == '/')
709 ; /* tolerate duplicated slashes */
710 if (!ch)
5f7b202a
JH
711 /* should not end with slashes */
712 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
713
714 /* we are at the beginning of the path component */
8558fd9e 715 if (ch == '.')
5f7b202a 716 return CHECK_REF_FORMAT_ERROR;
8558fd9e
DB
717 bad_type = bad_ref_char(ch);
718 if (bad_type) {
abd2bde7
DB
719 if (bad_type == 2 && (!*cp || *cp == '/') &&
720 ret == CHECK_REF_FORMAT_OK)
721 ret = CHECK_REF_FORMAT_WILDCARD;
722 else
723 return CHECK_REF_FORMAT_ERROR;
8558fd9e 724 }
03feddd6 725
cbdffe40 726 last = ch;
03feddd6
JH
727 /* scan the rest of the path component */
728 while ((ch = *cp++) != 0) {
8558fd9e 729 bad_type = bad_ref_char(ch);
cbdffe40 730 if (bad_type)
08fbdb30 731 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
732 if (ch == '/')
733 break;
cbdffe40
JH
734 if (last == '.' && ch == '.')
735 return CHECK_REF_FORMAT_ERROR;
736 if (last == '@' && ch == '{')
5f7b202a 737 return CHECK_REF_FORMAT_ERROR;
cbdffe40 738 last = ch;
03feddd6
JH
739 }
740 level++;
741 if (!ch) {
cbdffe40
JH
742 if (ref <= cp - 2 && cp[-2] == '.')
743 return CHECK_REF_FORMAT_ERROR;
03feddd6 744 if (level < 2)
5f7b202a 745 return CHECK_REF_FORMAT_ONELEVEL;
3e262b95
SP
746 if (has_extension(ref, ".lock"))
747 return CHECK_REF_FORMAT_ERROR;
abd2bde7 748 return ret;
03feddd6
JH
749 }
750 }
95fc7512
DB
751}
752
a9c37a72
DB
753const char *prettify_ref(const struct ref *ref)
754{
755 const char *name = ref->name;
756 return name + (
757 !prefixcmp(name, "refs/heads/") ? 11 :
758 !prefixcmp(name, "refs/tags/") ? 10 :
759 !prefixcmp(name, "refs/remotes/") ? 13 :
760 0);
761}
762
79803322
SP
763const char *ref_rev_parse_rules[] = {
764 "%.*s",
765 "refs/%.*s",
766 "refs/tags/%.*s",
767 "refs/heads/%.*s",
768 "refs/remotes/%.*s",
769 "refs/remotes/%.*s/HEAD",
770 NULL
771};
772
605b4978
SP
773const char *ref_fetch_rules[] = {
774 "%.*s",
775 "refs/%.*s",
776 "refs/heads/%.*s",
777 NULL
778};
779
79803322
SP
780int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
781{
782 const char **p;
783 const int abbrev_name_len = strlen(abbrev_name);
784
785 for (p = rules; *p; p++) {
786 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
787 return 1;
788 }
789 }
790
791 return 0;
792}
793
e5f38ec3 794static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
795 const unsigned char *old_sha1, int mustexist)
796{
8da19775 797 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 798 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
799 unlock_ref(lock);
800 return NULL;
801 }
a89fccd2 802 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 803 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
804 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
805 unlock_ref(lock);
806 return NULL;
807 }
808 return lock;
809}
810
7155b727 811static int remove_empty_directories(const char *file)
bc7127ef
JH
812{
813 /* we want to create a file but there is a directory there;
814 * if that is an empty directory (or a directory that contains
815 * only empty directories), remove them.
816 */
7155b727
JS
817 struct strbuf path;
818 int result;
bc7127ef 819
7155b727
JS
820 strbuf_init(&path, 20);
821 strbuf_addstr(&path, file);
822
823 result = remove_dir_recursively(&path, 1);
824
825 strbuf_release(&path);
826
827 return result;
bc7127ef
JH
828}
829
c976d415
LH
830static int is_refname_available(const char *ref, const char *oldref,
831 struct ref_list *list, int quiet)
832{
833 int namlen = strlen(ref); /* e.g. 'foo/bar' */
834 while (list) {
835 /* list->name could be 'foo' or 'foo/bar/baz' */
836 if (!oldref || strcmp(oldref, list->name)) {
837 int len = strlen(list->name);
838 int cmplen = (namlen < len) ? namlen : len;
839 const char *lead = (namlen < len) ? list->name : ref;
840 if (!strncmp(ref, list->name, cmplen) &&
841 lead[cmplen] == '/') {
842 if (!quiet)
843 error("'%s' exists; cannot create '%s'",
844 list->name, ref);
845 return 0;
846 }
847 }
848 list = list->next;
849 }
850 return 1;
851}
852
68db31cc 853static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
4bd18c43 854{
434cd0cd 855 char *ref_file;
ed378ec7 856 const char *orig_ref = ref;
4bd18c43 857 struct ref_lock *lock;
5cc3cef9 858 int last_errno = 0;
acd3b9ec 859 int type, lflags;
4431fcc4 860 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 861 int missing = 0;
4bd18c43
SP
862
863 lock = xcalloc(1, sizeof(struct ref_lock));
864 lock->lock_fd = -1;
865
68db31cc 866 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
bc7127ef
JH
867 if (!ref && errno == EISDIR) {
868 /* we are trying to lock foo but we used to
869 * have foo/bar which now does not exist;
870 * it is normal for the empty directory 'foo'
871 * to remain.
872 */
873 ref_file = git_path("%s", orig_ref);
5cc3cef9
JH
874 if (remove_empty_directories(ref_file)) {
875 last_errno = errno;
876 error("there are still refs under '%s'", orig_ref);
877 goto error_return;
878 }
68db31cc 879 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
bc7127ef 880 }
68db31cc
SV
881 if (type_p)
882 *type_p = type;
ed378ec7 883 if (!ref) {
5cc3cef9 884 last_errno = errno;
818f477c 885 error("unable to resolve reference %s: %s",
ed378ec7 886 orig_ref, strerror(errno));
5cc3cef9 887 goto error_return;
4bd18c43 888 }
5bdd8d4a 889 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
890 /* When the ref did not exist and we are creating it,
891 * make sure there is no existing ref that is packed
892 * whose name begins with our refname, nor a ref whose
893 * name is a proper prefix of our refname.
894 */
5bdd8d4a 895 if (missing &&
c976d415
LH
896 !is_refname_available(ref, NULL, get_packed_refs(), 0))
897 goto error_return;
22a3844e 898
c33d5174 899 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 900
acd3b9ec
JH
901 lflags = LOCK_DIE_ON_ERROR;
902 if (flags & REF_NODEREF) {
68db31cc 903 ref = orig_ref;
acd3b9ec
JH
904 lflags |= LOCK_NODEREF;
905 }
434cd0cd 906 lock->ref_name = xstrdup(ref);
1655707c 907 lock->orig_ref_name = xstrdup(orig_ref);
7c1a278d 908 ref_file = git_path("%s", ref);
5bdd8d4a 909 if (missing)
68db31cc
SV
910 lock->force_write = 1;
911 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
912 lock->force_write = 1;
4bd18c43 913
5cc3cef9
JH
914 if (safe_create_leading_directories(ref_file)) {
915 last_errno = errno;
916 error("unable to create directory for %s", ref_file);
917 goto error_return;
918 }
4bd18c43 919
acd3b9ec 920 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 921 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
922
923 error_return:
924 unlock_ref(lock);
925 errno = last_errno;
926 return NULL;
4bd18c43
SP
927}
928
4431fcc4 929struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
95fc7512 930{
53cce84c 931 char refpath[PATH_MAX];
95fc7512 932 if (check_ref_format(ref))
4bd18c43 933 return NULL;
53cce84c 934 strcpy(refpath, mkpath("refs/%s", ref));
68db31cc 935 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
936}
937
68db31cc 938struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
4bd18c43 939{
5f7b202a 940 switch (check_ref_format(ref)) {
5f7b202a 941 default:
257f3020
JH
942 return NULL;
943 case 0:
944 case CHECK_REF_FORMAT_ONELEVEL:
5f7b202a
JH
945 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
946 }
c0277d15
JH
947}
948
26a063a1
JH
949static struct lock_file packlock;
950
c0277d15
JH
951static int repack_without_ref(const char *refname)
952{
953 struct ref_list *list, *packed_ref_list;
954 int fd;
955 int found = 0;
c0277d15
JH
956
957 packed_ref_list = get_packed_refs();
958 for (list = packed_ref_list; list; list = list->next) {
959 if (!strcmp(refname, list->name)) {
960 found = 1;
961 break;
962 }
963 }
964 if (!found)
965 return 0;
c0277d15
JH
966 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
967 if (fd < 0)
968 return error("cannot delete '%s' from packed refs", refname);
969
970 for (list = packed_ref_list; list; list = list->next) {
971 char line[PATH_MAX + 100];
972 int len;
973
974 if (!strcmp(refname, list->name))
975 continue;
976 len = snprintf(line, sizeof(line), "%s %s\n",
977 sha1_to_hex(list->sha1), list->name);
978 /* this should not happen but just being defensive */
979 if (len > sizeof(line))
980 die("too long a refname '%s'", list->name);
981 write_or_die(fd, line, len);
982 }
983 return commit_lock_file(&packlock);
984}
985
eca35a25 986int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
987{
988 struct ref_lock *lock;
eca35a25 989 int err, i = 0, ret = 0, flag = 0;
c0277d15 990
68db31cc 991 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
992 if (!lock)
993 return 1;
045a476f 994 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 995 /* loose */
eca35a25
MV
996 const char *path;
997
998 if (!(delopt & REF_NODEREF)) {
999 i = strlen(lock->lk->filename) - 5; /* .lock */
1000 lock->lk->filename[i] = 0;
1001 path = lock->lk->filename;
1002 } else {
9db56f71 1003 path = git_path("%s", refname);
eca35a25
MV
1004 }
1005 err = unlink(path);
0b294c0a 1006 if (err && errno != ENOENT) {
c0277d15
JH
1007 ret = 1;
1008 error("unlink(%s) failed: %s",
eca35a25 1009 path, strerror(errno));
c0277d15 1010 }
eca35a25
MV
1011 if (!(delopt & REF_NODEREF))
1012 lock->lk->filename[i] = '.';
c0277d15
JH
1013 }
1014 /* removing the loose one could have resurrected an earlier
1015 * packed one. Also, if it was not loose we need to repack
1016 * without it.
1017 */
1018 ret |= repack_without_ref(refname);
1019
9a13f0b7 1020 err = unlink(git_path("logs/%s", lock->ref_name));
c0277d15 1021 if (err && errno != ENOENT)
edbc25c5 1022 warning("unlink(%s) failed: %s",
9a13f0b7 1023 git_path("logs/%s", lock->ref_name), strerror(errno));
c0277d15
JH
1024 invalidate_cached_refs();
1025 unlock_ref(lock);
1026 return ret;
4bd18c43
SP
1027}
1028
678d0f4c 1029int rename_ref(const char *oldref, const char *newref, const char *logmsg)
c976d415
LH
1030{
1031 static const char renamed_ref[] = "RENAMED-REF";
1032 unsigned char sha1[20], orig_sha1[20];
1033 int flag = 0, logmoved = 0;
1034 struct ref_lock *lock;
c976d415 1035 struct stat loginfo;
16c2bfbb 1036 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
eca35a25 1037 const char *symref = NULL;
c976d415 1038
450d4c0f 1039 if (log && S_ISLNK(loginfo.st_mode))
c976d415
LH
1040 return error("reflog for %s is a symlink", oldref);
1041
eca35a25
MV
1042 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1043 if (flag & REF_ISSYMREF)
fa58186c
MV
1044 return error("refname %s is a symbolic ref, renaming it is not supported",
1045 oldref);
eca35a25 1046 if (!symref)
c976d415
LH
1047 return error("refname %s not found", oldref);
1048
1049 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1050 return 1;
1051
1052 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1053 return 1;
1054
68db31cc 1055 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
c976d415
LH
1056 if (!lock)
1057 return error("unable to lock %s", renamed_ref);
1058 lock->force_write = 1;
678d0f4c 1059 if (write_ref_sha1(lock, orig_sha1, logmsg))
c976d415
LH
1060 return error("unable to save current sha1 in %s", renamed_ref);
1061
1062 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1063 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1064 oldref, strerror(errno));
1065
eca35a25 1066 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
c976d415
LH
1067 error("unable to delete old %s", oldref);
1068 goto rollback;
1069 }
1070
eca35a25 1071 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
c976d415
LH
1072 if (errno==EISDIR) {
1073 if (remove_empty_directories(git_path("%s", newref))) {
1074 error("Directory not empty: %s", newref);
1075 goto rollback;
1076 }
1077 } else {
1078 error("unable to delete existing %s", newref);
1079 goto rollback;
1080 }
1081 }
1082
1083 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1084 error("unable to create directory for %s", newref);
1085 goto rollback;
1086 }
1087
1088 retry:
1089 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
d9e74d57
JR
1090 if (errno==EISDIR || errno==ENOTDIR) {
1091 /*
1092 * rename(a, b) when b is an existing
1093 * directory ought to result in ISDIR, but
1094 * Solaris 5.8 gives ENOTDIR. Sheesh.
1095 */
c976d415
LH
1096 if (remove_empty_directories(git_path("logs/%s", newref))) {
1097 error("Directory not empty: logs/%s", newref);
1098 goto rollback;
1099 }
1100 goto retry;
1101 } else {
1102 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1103 newref, strerror(errno));
1104 goto rollback;
1105 }
1106 }
1107 logmoved = log;
1108
68db31cc 1109 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
c976d415
LH
1110 if (!lock) {
1111 error("unable to lock %s for update", newref);
1112 goto rollback;
1113 }
c976d415
LH
1114 lock->force_write = 1;
1115 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1116 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
c976d415
LH
1117 error("unable to write current sha1 into %s", newref);
1118 goto rollback;
1119 }
1120
1121 return 0;
1122
1123 rollback:
68db31cc 1124 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
c976d415
LH
1125 if (!lock) {
1126 error("unable to lock %s for rollback", oldref);
1127 goto rollbacklog;
1128 }
1129
1130 lock->force_write = 1;
1131 flag = log_all_ref_updates;
1132 log_all_ref_updates = 0;
1133 if (write_ref_sha1(lock, orig_sha1, NULL))
1134 error("unable to write current sha1 into %s", oldref);
1135 log_all_ref_updates = flag;
1136
1137 rollbacklog:
1138 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1139 error("unable to restore logfile %s from %s: %s",
1140 oldref, newref, strerror(errno));
1141 if (!logmoved && log &&
1142 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1143 error("unable to restore logfile %s from tmp-renamed-log: %s",
1144 oldref, strerror(errno));
1145
1146 return 1;
1147}
1148
435fc852 1149int close_ref(struct ref_lock *lock)
b531394d
BC
1150{
1151 if (close_lock_file(lock->lk))
1152 return -1;
1153 lock->lock_fd = -1;
1154 return 0;
1155}
1156
435fc852 1157int commit_ref(struct ref_lock *lock)
b531394d
BC
1158{
1159 if (commit_lock_file(lock->lk))
1160 return -1;
1161 lock->lock_fd = -1;
1162 return 0;
1163}
1164
e5f38ec3 1165void unlock_ref(struct ref_lock *lock)
4bd18c43 1166{
4ed7cd3a
BC
1167 /* Do not free lock->lk -- atexit() still looks at them */
1168 if (lock->lk)
1169 rollback_lock_file(lock->lk);
434cd0cd 1170 free(lock->ref_name);
1655707c 1171 free(lock->orig_ref_name);
4bd18c43
SP
1172 free(lock);
1173}
1174
0ec29a47
JH
1175/*
1176 * copy the reflog message msg to buf, which has been allocated sufficiently
1177 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1178 * because reflog file is one line per entry.
1179 */
1180static int copy_msg(char *buf, const char *msg)
1181{
1182 char *cp = buf;
1183 char c;
1184 int wasspace = 1;
1185
1186 *cp++ = '\t';
1187 while ((c = *msg++)) {
1188 if (wasspace && isspace(c))
1189 continue;
1190 wasspace = isspace(c);
1191 if (wasspace)
1192 c = ' ';
1193 *cp++ = c;
1194 }
1195 while (buf < cp && isspace(cp[-1]))
1196 cp--;
1197 *cp++ = '\n';
1198 return cp - buf;
1199}
1200
9a13f0b7
NP
1201static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1202 const unsigned char *new_sha1, const char *msg)
6de08ae6
SP
1203{
1204 int logfd, written, oflags = O_APPEND | O_WRONLY;
1205 unsigned maxlen, len;
8ac65937 1206 int msglen;
958a4789
AR
1207 char log_file[PATH_MAX];
1208 char *logrec;
ff4c8485 1209 const char *committer;
6de08ae6 1210
510c5a8e 1211 if (log_all_ref_updates < 0)
7d1864ce 1212 log_all_ref_updates = !is_bare_repository();
510c5a8e 1213
958a4789 1214 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
9a13f0b7 1215
4057deb5 1216 if (log_all_ref_updates &&
cc44c765
JH
1217 (!prefixcmp(ref_name, "refs/heads/") ||
1218 !prefixcmp(ref_name, "refs/remotes/") ||
bd104db1 1219 !strcmp(ref_name, "HEAD"))) {
9a13f0b7 1220 if (safe_create_leading_directories(log_file) < 0)
6de08ae6 1221 return error("unable to create directory for %s",
9a13f0b7 1222 log_file);
6de08ae6
SP
1223 oflags |= O_CREAT;
1224 }
1225
9a13f0b7 1226 logfd = open(log_file, oflags, 0666);
6de08ae6 1227 if (logfd < 0) {
1974bf62 1228 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1229 return 0;
3b463c3f
JH
1230
1231 if ((oflags & O_CREAT) && errno == EISDIR) {
9a13f0b7 1232 if (remove_empty_directories(log_file)) {
3b463c3f 1233 return error("There are still logs under '%s'",
9a13f0b7 1234 log_file);
3b463c3f 1235 }
9a13f0b7 1236 logfd = open(log_file, oflags, 0666);
3b463c3f
JH
1237 }
1238
1239 if (logfd < 0)
1240 return error("Unable to append to %s: %s",
9a13f0b7 1241 log_file, strerror(errno));
6de08ae6
SP
1242 }
1243
443b92b6
MK
1244 adjust_shared_perm(log_file);
1245
0ec29a47 1246 msglen = msg ? strlen(msg) : 0;
774751a8 1247 committer = git_committer_info(0);
8ac65937
JH
1248 maxlen = strlen(committer) + msglen + 100;
1249 logrec = xmalloc(maxlen);
1250 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1251 sha1_to_hex(old_sha1),
1252 sha1_to_hex(new_sha1),
8ac65937
JH
1253 committer);
1254 if (msglen)
0ec29a47 1255 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1256 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1257 free(logrec);
91c8d590 1258 if (close(logfd) != 0 || written != len)
9a13f0b7 1259 return error("Unable to append to %s", log_file);
6de08ae6
SP
1260 return 0;
1261}
1262
c3b0dec5
LT
1263static int is_branch(const char *refname)
1264{
1265 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1266}
1267
4bd18c43
SP
1268int write_ref_sha1(struct ref_lock *lock,
1269 const unsigned char *sha1, const char *logmsg)
1270{
1271 static char term = '\n';
c3b0dec5 1272 struct object *o;
4bd18c43
SP
1273
1274 if (!lock)
95fc7512 1275 return -1;
a89fccd2 1276 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1277 unlock_ref(lock);
1278 return 0;
95fc7512 1279 }
c3b0dec5
LT
1280 o = parse_object(sha1);
1281 if (!o) {
1282 error("Trying to write ref %s with nonexistant object %s",
1283 lock->ref_name, sha1_to_hex(sha1));
1284 unlock_ref(lock);
1285 return -1;
1286 }
1287 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1288 error("Trying to write non-commit object %s to branch %s",
1289 sha1_to_hex(sha1), lock->ref_name);
1290 unlock_ref(lock);
1291 return -1;
1292 }
93822c22
AW
1293 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1294 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1295 || close_ref(lock) < 0) {
c33d5174 1296 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1297 unlock_ref(lock);
1298 return -1;
1299 }
5e290ff7 1300 invalidate_cached_refs();
bd104db1
NP
1301 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1302 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1303 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1304 unlock_ref(lock);
1305 return -1;
1306 }
605fac8b
NP
1307 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1308 /*
1309 * Special hack: If a branch is updated directly and HEAD
1310 * points to it (may happen on the remote side of a push
1311 * for example) then logically the HEAD reflog should be
1312 * updated too.
1313 * A generic solution implies reverse symref information,
1314 * but finding all symrefs pointing to the given branch
1315 * would be rather costly for this rare event (the direct
1316 * update of a branch) to be worth it. So let's cheat and
1317 * check with HEAD only which should cover 99% of all usage
1318 * scenarios (even 100% of the default ones).
1319 */
1320 unsigned char head_sha1[20];
1321 int head_flag;
1322 const char *head_ref;
1323 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1324 if (head_ref && (head_flag & REF_ISSYMREF) &&
1325 !strcmp(head_ref, lock->ref_name))
1326 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1327 }
b531394d 1328 if (commit_ref(lock)) {
434cd0cd 1329 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1330 unlock_ref(lock);
1331 return -1;
1332 }
4bd18c43
SP
1333 unlock_ref(lock);
1334 return 0;
95fc7512 1335}
d556fae2 1336
8b5157e4
NP
1337int create_symref(const char *ref_target, const char *refs_heads_master,
1338 const char *logmsg)
41b625b0
NP
1339{
1340 const char *lockpath;
1341 char ref[1000];
1342 int fd, len, written;
a4f34cbb 1343 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1344 unsigned char old_sha1[20], new_sha1[20];
1345
1346 if (logmsg && read_ref(ref_target, old_sha1))
1347 hashclr(old_sha1);
41b625b0 1348
d48744d1
JH
1349 if (safe_create_leading_directories(git_HEAD) < 0)
1350 return error("unable to create directory for %s", git_HEAD);
1351
41b625b0
NP
1352#ifndef NO_SYMLINK_HEAD
1353 if (prefer_symlink_refs) {
1354 unlink(git_HEAD);
1355 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1356 goto done;
41b625b0
NP
1357 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1358 }
1359#endif
1360
1361 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1362 if (sizeof(ref) <= len) {
1363 error("refname too long: %s", refs_heads_master);
47fc52e2 1364 goto error_free_return;
41b625b0
NP
1365 }
1366 lockpath = mkpath("%s.lock", git_HEAD);
1367 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1368 if (fd < 0) {
1369 error("Unable to open %s for writing", lockpath);
47fc52e2 1370 goto error_free_return;
41b625b0
NP
1371 }
1372 written = write_in_full(fd, ref, len);
91c8d590 1373 if (close(fd) != 0 || written != len) {
41b625b0 1374 error("Unable to write to %s", lockpath);
47fc52e2 1375 goto error_unlink_return;
41b625b0
NP
1376 }
1377 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1378 error("Unable to create %s", git_HEAD);
47fc52e2 1379 goto error_unlink_return;
41b625b0
NP
1380 }
1381 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1382 error("Unable to fix permissions on %s", lockpath);
47fc52e2
JH
1383 error_unlink_return:
1384 unlink(lockpath);
1385 error_free_return:
1386 free(git_HEAD);
1387 return -1;
41b625b0 1388 }
8b5157e4 1389
ee96d11b 1390#ifndef NO_SYMLINK_HEAD
8b5157e4 1391 done:
ee96d11b 1392#endif
8b5157e4
NP
1393 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1394 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1395
47fc52e2 1396 free(git_HEAD);
41b625b0
NP
1397 return 0;
1398}
1399
16d7cc90
JH
1400static char *ref_msg(const char *line, const char *endp)
1401{
1402 const char *ep;
16d7cc90 1403 line += 82;
182af834
PH
1404 ep = memchr(line, '\n', endp - line);
1405 if (!ep)
1406 ep = endp;
1407 return xmemdupz(line, ep - line);
16d7cc90
JH
1408}
1409
1410int 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 1411{
e5229042 1412 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1413 char *tz_c;
e29cb53a 1414 int logfd, tz, reccnt = 0;
d556fae2
SP
1415 struct stat st;
1416 unsigned long date;
e5229042 1417 unsigned char logged_sha1[20];
cb48cb58 1418 void *log_mapped;
dc49cd76 1419 size_t mapsz;
d556fae2
SP
1420
1421 logfile = git_path("logs/%s", ref);
1422 logfd = open(logfile, O_RDONLY, 0);
1423 if (logfd < 0)
1424 die("Unable to read log %s: %s", logfile, strerror(errno));
1425 fstat(logfd, &st);
1426 if (!st.st_size)
1427 die("Log %s is empty.", logfile);
dc49cd76
SP
1428 mapsz = xsize_t(st.st_size);
1429 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1430 logdata = log_mapped;
d556fae2
SP
1431 close(logfd);
1432
e5229042 1433 lastrec = NULL;
d556fae2
SP
1434 rec = logend = logdata + st.st_size;
1435 while (logdata < rec) {
e29cb53a 1436 reccnt++;
d556fae2
SP
1437 if (logdata < rec && *(rec-1) == '\n')
1438 rec--;
e5229042
SP
1439 lastgt = NULL;
1440 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1441 rec--;
e5229042
SP
1442 if (*rec == '>')
1443 lastgt = rec;
1444 }
1445 if (!lastgt)
d556fae2 1446 die("Log %s is corrupt.", logfile);
e5229042 1447 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1448 if (date <= at_time || cnt == 0) {
76a44c5c 1449 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1450 if (msg)
1451 *msg = ref_msg(rec, logend);
1452 if (cutoff_time)
1453 *cutoff_time = date;
1454 if (cutoff_tz)
1455 *cutoff_tz = tz;
1456 if (cutoff_cnt)
76a44c5c 1457 *cutoff_cnt = reccnt - 1;
e5229042
SP
1458 if (lastrec) {
1459 if (get_sha1_hex(lastrec, logged_sha1))
1460 die("Log %s is corrupt.", logfile);
1461 if (get_sha1_hex(rec + 41, sha1))
1462 die("Log %s is corrupt.", logfile);
a89fccd2 1463 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1464 warning("Log %s has gap after %s.",
73013afd 1465 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1466 }
e5f38ec3
JH
1467 }
1468 else if (date == at_time) {
e5229042
SP
1469 if (get_sha1_hex(rec + 41, sha1))
1470 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1471 }
1472 else {
e5229042
SP
1473 if (get_sha1_hex(rec + 41, logged_sha1))
1474 die("Log %s is corrupt.", logfile);
a89fccd2 1475 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1476 warning("Log %s unexpectedly ended on %s.",
73013afd 1477 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1478 }
1479 }
dc49cd76 1480 munmap(log_mapped, mapsz);
d556fae2
SP
1481 return 0;
1482 }
e5229042 1483 lastrec = rec;
ab2a1a32
JH
1484 if (cnt > 0)
1485 cnt--;
d556fae2
SP
1486 }
1487
e5229042
SP
1488 rec = logdata;
1489 while (rec < logend && *rec != '>' && *rec != '\n')
1490 rec++;
1491 if (rec == logend || *rec == '\n')
d556fae2 1492 die("Log %s is corrupt.", logfile);
e5229042 1493 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1494 tz = strtoul(tz_c, NULL, 10);
1495 if (get_sha1_hex(logdata, sha1))
1496 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1497 if (is_null_sha1(sha1)) {
1498 if (get_sha1_hex(logdata + 41, sha1))
1499 die("Log %s is corrupt.", logfile);
1500 }
16d7cc90
JH
1501 if (msg)
1502 *msg = ref_msg(logdata, logend);
dc49cd76 1503 munmap(log_mapped, mapsz);
16d7cc90
JH
1504
1505 if (cutoff_time)
1506 *cutoff_time = date;
1507 if (cutoff_tz)
1508 *cutoff_tz = tz;
1509 if (cutoff_cnt)
1510 *cutoff_cnt = reccnt;
1511 return 1;
d556fae2 1512}
2ff81662 1513
101d15e0 1514int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
1515{
1516 const char *logfile;
1517 FILE *logfp;
1518 char buf[1024];
2266bf27 1519 int ret = 0;
2ff81662
JH
1520
1521 logfile = git_path("logs/%s", ref);
1522 logfp = fopen(logfile, "r");
1523 if (!logfp)
883d60fa 1524 return -1;
101d15e0
JH
1525
1526 if (ofs) {
1527 struct stat statbuf;
1528 if (fstat(fileno(logfp), &statbuf) ||
1529 statbuf.st_size < ofs ||
1530 fseek(logfp, -ofs, SEEK_END) ||
1531 fgets(buf, sizeof(buf), logfp))
1532 return -1;
1533 }
1534
2ff81662
JH
1535 while (fgets(buf, sizeof(buf), logfp)) {
1536 unsigned char osha1[20], nsha1[20];
883d60fa
JS
1537 char *email_end, *message;
1538 unsigned long timestamp;
2266bf27 1539 int len, tz;
2ff81662
JH
1540
1541 /* old SP new SP name <email> SP time TAB msg LF */
1542 len = strlen(buf);
1543 if (len < 83 || buf[len-1] != '\n' ||
1544 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
883d60fa
JS
1545 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1546 !(email_end = strchr(buf + 82, '>')) ||
1547 email_end[1] != ' ' ||
1548 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1549 !message || message[0] != ' ' ||
1550 (message[1] != '+' && message[1] != '-') ||
1551 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 1552 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 1553 continue; /* corrupt? */
883d60fa
JS
1554 email_end[1] = '\0';
1555 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
1556 if (message[6] != '\t')
1557 message += 6;
1558 else
1559 message += 7;
883d60fa
JS
1560 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1561 if (ret)
2266bf27 1562 break;
2ff81662
JH
1563 }
1564 fclose(logfp);
2266bf27 1565 return ret;
2ff81662 1566}
e29cb53a 1567
101d15e0
JH
1568int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1569{
1570 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1571}
1572
eb8381c8
NP
1573static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1574{
1575 DIR *dir = opendir(git_path("logs/%s", base));
fcee5a14 1576 int retval = 0;
eb8381c8
NP
1577
1578 if (dir) {
1579 struct dirent *de;
1580 int baselen = strlen(base);
1581 char *log = xmalloc(baselen + 257);
1582
1583 memcpy(log, base, baselen);
1584 if (baselen && base[baselen-1] != '/')
1585 log[baselen++] = '/';
1586
1587 while ((de = readdir(dir)) != NULL) {
1588 struct stat st;
1589 int namelen;
1590
1591 if (de->d_name[0] == '.')
1592 continue;
1593 namelen = strlen(de->d_name);
1594 if (namelen > 255)
1595 continue;
1596 if (has_extension(de->d_name, ".lock"))
1597 continue;
1598 memcpy(log + baselen, de->d_name, namelen+1);
1599 if (stat(git_path("logs/%s", log), &st) < 0)
1600 continue;
1601 if (S_ISDIR(st.st_mode)) {
1602 retval = do_for_each_reflog(log, fn, cb_data);
1603 } else {
1604 unsigned char sha1[20];
1605 if (!resolve_ref(log, sha1, 0, NULL))
1606 retval = error("bad ref for %s", log);
1607 else
1608 retval = fn(log, sha1, 0, cb_data);
1609 }
1610 if (retval)
1611 break;
1612 }
1613 free(log);
1614 closedir(dir);
1615 }
acb39f64 1616 else if (*base)
fcee5a14 1617 return errno;
eb8381c8
NP
1618 return retval;
1619}
1620
1621int for_each_reflog(each_ref_fn fn, void *cb_data)
1622{
1623 return do_for_each_reflog("", fn, cb_data);
1624}
3d9f037c
CR
1625
1626int update_ref(const char *action, const char *refname,
1627 const unsigned char *sha1, const unsigned char *oldval,
1628 int flags, enum action_on_err onerr)
1629{
1630 static struct ref_lock *lock;
1631 lock = lock_any_ref_for_update(refname, oldval, flags);
1632 if (!lock) {
1633 const char *str = "Cannot lock the ref '%s'.";
1634 switch (onerr) {
1635 case MSG_ON_ERR: error(str, refname); break;
1636 case DIE_ON_ERR: die(str, refname); break;
1637 case QUIET_ON_ERR: break;
1638 }
1639 return 1;
1640 }
1641 if (write_ref_sha1(lock, sha1, action) < 0) {
1642 const char *str = "Cannot update the ref '%s'.";
1643 switch (onerr) {
1644 case MSG_ON_ERR: error(str, refname); break;
1645 case DIE_ON_ERR: die(str, refname); break;
1646 case QUIET_ON_ERR: break;
1647 }
1648 return 1;
1649 }
1650 return 0;
1651}
cda69f48 1652
5483f799 1653struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
1654{
1655 for ( ; list; list = list->next)
1656 if (!strcmp(list->name, name))
5483f799 1657 return (struct ref *)list;
cda69f48
JK
1658 return NULL;
1659}
7c2b3029
JK
1660
1661/*
1662 * generate a format suitable for scanf from a ref_rev_parse_rules
1663 * rule, that is replace the "%.*s" spec with a "%s" spec
1664 */
1665static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1666{
1667 char *spec;
1668
1669 spec = strstr(rule, "%.*s");
1670 if (!spec || strstr(spec + 4, "%.*s"))
1671 die("invalid rule in ref_rev_parse_rules: %s", rule);
1672
1673 /* copy all until spec */
1674 strncpy(scanf_fmt, rule, spec - rule);
1675 scanf_fmt[spec - rule] = '\0';
1676 /* copy new spec */
1677 strcat(scanf_fmt, "%s");
1678 /* copy remaining rule */
1679 strcat(scanf_fmt, spec + 4);
1680
1681 return;
1682}
1683
1684char *shorten_unambiguous_ref(const char *ref)
1685{
1686 int i;
1687 static char **scanf_fmts;
1688 static int nr_rules;
1689 char *short_name;
1690
1691 /* pre generate scanf formats from ref_rev_parse_rules[] */
1692 if (!nr_rules) {
1693 size_t total_len = 0;
1694
1695 /* the rule list is NULL terminated, count them first */
1696 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1697 /* no +1 because strlen("%s") < strlen("%.*s") */
1698 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1699
1700 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1701
1702 total_len = 0;
1703 for (i = 0; i < nr_rules; i++) {
1704 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1705 + total_len;
1706 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1707 total_len += strlen(ref_rev_parse_rules[i]);
1708 }
1709 }
1710
1711 /* bail out if there are no rules */
1712 if (!nr_rules)
1713 return xstrdup(ref);
1714
1715 /* buffer for scanf result, at most ref must fit */
1716 short_name = xstrdup(ref);
1717
1718 /* skip first rule, it will always match */
1719 for (i = nr_rules - 1; i > 0 ; --i) {
1720 int j;
1721 int short_name_len;
1722
1723 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1724 continue;
1725
1726 short_name_len = strlen(short_name);
1727
1728 /*
1729 * check if the short name resolves to a valid ref,
1730 * but use only rules prior to the matched one
1731 */
1732 for (j = 0; j < i; j++) {
1733 const char *rule = ref_rev_parse_rules[j];
1734 unsigned char short_objectname[20];
1735 char refname[PATH_MAX];
1736
1737 /*
1738 * the short name is ambiguous, if it resolves
1739 * (with this previous rule) to a valid ref
1740 * read_ref() returns 0 on success
1741 */
1742 mksnpath(refname, sizeof(refname),
1743 rule, short_name_len, short_name);
1744 if (!read_ref(refname, short_objectname))
1745 break;
1746 }
1747
1748 /*
1749 * short name is non-ambiguous if all previous rules
1750 * haven't resolved to a valid ref
1751 */
1752 if (j == i)
1753 return short_name;
1754 }
1755
1756 free(short_name);
1757 return xstrdup(ref);
1758}