clean: require double -f options to nuke nested git repository and work tree
[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;
eafb4526
JH
534 /* Is this a "negative ref" that represents a deleted ref? */
535 if (is_null_sha1(entry->sha1))
536 return 0;
f8948e2f 537 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
f8948e2f
JH
538 if (!has_sha1_file(entry->sha1)) {
539 error("%s does not point to a valid object!", entry->name);
540 return 0;
541 }
ef06b918 542 }
0ae91be0 543 current_ref = entry;
ef06b918
JH
544 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
545}
546
cf0adba7
JH
547int peel_ref(const char *ref, unsigned char *sha1)
548{
549 int flag;
550 unsigned char base[20];
551 struct object *o;
552
0ae91be0
SP
553 if (current_ref && (current_ref->name == ref
554 || !strcmp(current_ref->name, ref))) {
555 if (current_ref->flag & REF_KNOWS_PEELED) {
556 hashcpy(sha1, current_ref->peeled);
557 return 0;
558 }
559 hashcpy(base, current_ref->sha1);
560 goto fallback;
561 }
562
cf0adba7
JH
563 if (!resolve_ref(ref, base, 1, &flag))
564 return -1;
565
566 if ((flag & REF_ISPACKED)) {
567 struct ref_list *list = get_packed_refs();
cf0adba7
JH
568
569 while (list) {
f4204ab9
JH
570 if (!strcmp(list->name, ref)) {
571 if (list->flag & REF_KNOWS_PEELED) {
572 hashcpy(sha1, list->peeled);
573 return 0;
574 }
575 /* older pack-refs did not leave peeled ones */
576 break;
cf0adba7
JH
577 }
578 list = list->next;
579 }
cf0adba7
JH
580 }
581
0ae91be0 582fallback:
cf0adba7 583 o = parse_object(base);
8c87dc77 584 if (o && o->type == OBJ_TAG) {
cf0adba7
JH
585 o = deref_tag(o, ref, 0);
586 if (o) {
587 hashcpy(sha1, o->sha1);
588 return 0;
589 }
590 }
591 return -1;
592}
593
8da19775 594static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 595 int flags, void *cb_data)
8a65ff76 596{
0ae91be0 597 int retval = 0;
e1e22e37
LT
598 struct ref_list *packed = get_packed_refs();
599 struct ref_list *loose = get_loose_refs();
8a65ff76 600
e142a3c6
DB
601 struct ref_list *extra;
602
603 for (extra = extra_refs; extra; extra = extra->next)
f8948e2f 604 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
e142a3c6 605
e1e22e37
LT
606 while (packed && loose) {
607 struct ref_list *entry;
608 int cmp = strcmp(packed->name, loose->name);
609 if (!cmp) {
610 packed = packed->next;
611 continue;
6cada6a9 612 }
e1e22e37
LT
613 if (cmp > 0) {
614 entry = loose;
615 loose = loose->next;
616 } else {
617 entry = packed;
618 packed = packed->next;
619 }
f8948e2f 620 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
e1e22e37 621 if (retval)
0ae91be0 622 goto end_each;
e1e22e37 623 }
8a65ff76 624
ef06b918 625 for (packed = packed ? packed : loose; packed; packed = packed->next) {
f8948e2f 626 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
ef06b918 627 if (retval)
0ae91be0 628 goto end_each;
8a65ff76 629 }
0ae91be0
SP
630
631end_each:
632 current_ref = NULL;
633 return retval;
8a65ff76
LT
634}
635
cb5d709f 636int head_ref(each_ref_fn fn, void *cb_data)
723c31fe
LT
637{
638 unsigned char sha1[20];
8da19775
JH
639 int flag;
640
641 if (resolve_ref("HEAD", sha1, 1, &flag))
642 return fn("HEAD", sha1, flag, cb_data);
2f34ba32 643 return 0;
723c31fe
LT
644}
645
cb5d709f 646int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 647{
f8948e2f 648 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
a62be77f
SE
649}
650
2a8177b6
CC
651int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
652{
653 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
654}
655
cb5d709f 656int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 657{
2a8177b6 658 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
659}
660
cb5d709f 661int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 662{
2a8177b6 663 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
664}
665
cb5d709f 666int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 667{
2a8177b6 668 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
669}
670
671int for_each_rawref(each_ref_fn fn, void *cb_data)
672{
673 return do_for_each_ref("refs/", fn, 0,
674 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
675}
676
03feddd6
JH
677/*
678 * Make sure "ref" is something reasonable to have under ".git/refs/";
679 * We do not like it if:
680 *
681 * - any path component of it begins with ".", or
682 * - it has double dots "..", or
683 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
684 * - it ends with a "/".
3e262b95 685 * - it ends with ".lock"
a4c2e699 686 * - it contains a "\" (backslash)
03feddd6
JH
687 */
688
689static inline int bad_ref_char(int ch)
690{
8558fd9e 691 if (((unsigned) ch) <= ' ' ||
a4c2e699 692 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
8558fd9e
DB
693 return 1;
694 /* 2.13 Pattern Matching Notation */
695 if (ch == '?' || ch == '[') /* Unsupported */
696 return 1;
697 if (ch == '*') /* Supported at the end */
698 return 2;
699 return 0;
03feddd6
JH
700}
701
95fc7512
DB
702int check_ref_format(const char *ref)
703{
cbdffe40 704 int ch, level, bad_type, last;
abd2bde7 705 int ret = CHECK_REF_FORMAT_OK;
03feddd6
JH
706 const char *cp = ref;
707
708 level = 0;
709 while (1) {
710 while ((ch = *cp++) == '/')
711 ; /* tolerate duplicated slashes */
712 if (!ch)
5f7b202a
JH
713 /* should not end with slashes */
714 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
715
716 /* we are at the beginning of the path component */
8558fd9e 717 if (ch == '.')
5f7b202a 718 return CHECK_REF_FORMAT_ERROR;
8558fd9e
DB
719 bad_type = bad_ref_char(ch);
720 if (bad_type) {
abd2bde7
DB
721 if (bad_type == 2 && (!*cp || *cp == '/') &&
722 ret == CHECK_REF_FORMAT_OK)
723 ret = CHECK_REF_FORMAT_WILDCARD;
724 else
725 return CHECK_REF_FORMAT_ERROR;
8558fd9e 726 }
03feddd6 727
cbdffe40 728 last = ch;
03feddd6
JH
729 /* scan the rest of the path component */
730 while ((ch = *cp++) != 0) {
8558fd9e 731 bad_type = bad_ref_char(ch);
cbdffe40 732 if (bad_type)
08fbdb30 733 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
734 if (ch == '/')
735 break;
cbdffe40
JH
736 if (last == '.' && ch == '.')
737 return CHECK_REF_FORMAT_ERROR;
738 if (last == '@' && ch == '{')
5f7b202a 739 return CHECK_REF_FORMAT_ERROR;
cbdffe40 740 last = ch;
03feddd6
JH
741 }
742 level++;
743 if (!ch) {
cbdffe40
JH
744 if (ref <= cp - 2 && cp[-2] == '.')
745 return CHECK_REF_FORMAT_ERROR;
03feddd6 746 if (level < 2)
5f7b202a 747 return CHECK_REF_FORMAT_ONELEVEL;
3e262b95
SP
748 if (has_extension(ref, ".lock"))
749 return CHECK_REF_FORMAT_ERROR;
abd2bde7 750 return ret;
03feddd6
JH
751 }
752 }
95fc7512
DB
753}
754
4577e483 755const char *prettify_refname(const char *name)
a9c37a72 756{
a9c37a72
DB
757 return name + (
758 !prefixcmp(name, "refs/heads/") ? 11 :
759 !prefixcmp(name, "refs/tags/") ? 10 :
760 !prefixcmp(name, "refs/remotes/") ? 13 :
761 0);
762}
763
79803322
SP
764const char *ref_rev_parse_rules[] = {
765 "%.*s",
766 "refs/%.*s",
767 "refs/tags/%.*s",
768 "refs/heads/%.*s",
769 "refs/remotes/%.*s",
770 "refs/remotes/%.*s/HEAD",
771 NULL
772};
773
605b4978
SP
774const char *ref_fetch_rules[] = {
775 "%.*s",
776 "refs/%.*s",
777 "refs/heads/%.*s",
778 NULL
779};
780
79803322
SP
781int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
782{
783 const char **p;
784 const int abbrev_name_len = strlen(abbrev_name);
785
786 for (p = rules; *p; p++) {
787 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
788 return 1;
789 }
790 }
791
792 return 0;
793}
794
e5f38ec3 795static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
796 const unsigned char *old_sha1, int mustexist)
797{
8da19775 798 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 799 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
800 unlock_ref(lock);
801 return NULL;
802 }
a89fccd2 803 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 804 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
805 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
806 unlock_ref(lock);
807 return NULL;
808 }
809 return lock;
810}
811
7155b727 812static int remove_empty_directories(const char *file)
bc7127ef
JH
813{
814 /* we want to create a file but there is a directory there;
815 * if that is an empty directory (or a directory that contains
816 * only empty directories), remove them.
817 */
7155b727
JS
818 struct strbuf path;
819 int result;
bc7127ef 820
7155b727
JS
821 strbuf_init(&path, 20);
822 strbuf_addstr(&path, file);
823
a0f4afbe 824 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
825
826 strbuf_release(&path);
827
828 return result;
bc7127ef
JH
829}
830
c976d415
LH
831static int is_refname_available(const char *ref, const char *oldref,
832 struct ref_list *list, int quiet)
833{
834 int namlen = strlen(ref); /* e.g. 'foo/bar' */
835 while (list) {
836 /* list->name could be 'foo' or 'foo/bar/baz' */
837 if (!oldref || strcmp(oldref, list->name)) {
838 int len = strlen(list->name);
839 int cmplen = (namlen < len) ? namlen : len;
840 const char *lead = (namlen < len) ? list->name : ref;
841 if (!strncmp(ref, list->name, cmplen) &&
842 lead[cmplen] == '/') {
843 if (!quiet)
844 error("'%s' exists; cannot create '%s'",
845 list->name, ref);
846 return 0;
847 }
848 }
849 list = list->next;
850 }
851 return 1;
852}
853
68db31cc 854static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
4bd18c43 855{
434cd0cd 856 char *ref_file;
ed378ec7 857 const char *orig_ref = ref;
4bd18c43 858 struct ref_lock *lock;
5cc3cef9 859 int last_errno = 0;
acd3b9ec 860 int type, lflags;
4431fcc4 861 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 862 int missing = 0;
4bd18c43
SP
863
864 lock = xcalloc(1, sizeof(struct ref_lock));
865 lock->lock_fd = -1;
866
68db31cc 867 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
bc7127ef
JH
868 if (!ref && errno == EISDIR) {
869 /* we are trying to lock foo but we used to
870 * have foo/bar which now does not exist;
871 * it is normal for the empty directory 'foo'
872 * to remain.
873 */
874 ref_file = git_path("%s", orig_ref);
5cc3cef9
JH
875 if (remove_empty_directories(ref_file)) {
876 last_errno = errno;
877 error("there are still refs under '%s'", orig_ref);
878 goto error_return;
879 }
68db31cc 880 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
bc7127ef 881 }
68db31cc
SV
882 if (type_p)
883 *type_p = type;
ed378ec7 884 if (!ref) {
5cc3cef9 885 last_errno = errno;
818f477c 886 error("unable to resolve reference %s: %s",
ed378ec7 887 orig_ref, strerror(errno));
5cc3cef9 888 goto error_return;
4bd18c43 889 }
5bdd8d4a 890 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
891 /* When the ref did not exist and we are creating it,
892 * make sure there is no existing ref that is packed
893 * whose name begins with our refname, nor a ref whose
894 * name is a proper prefix of our refname.
895 */
5bdd8d4a 896 if (missing &&
f475e08e
JK
897 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
898 last_errno = ENOTDIR;
c976d415 899 goto error_return;
f475e08e 900 }
22a3844e 901
c33d5174 902 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 903
acd3b9ec
JH
904 lflags = LOCK_DIE_ON_ERROR;
905 if (flags & REF_NODEREF) {
68db31cc 906 ref = orig_ref;
acd3b9ec
JH
907 lflags |= LOCK_NODEREF;
908 }
434cd0cd 909 lock->ref_name = xstrdup(ref);
1655707c 910 lock->orig_ref_name = xstrdup(orig_ref);
7c1a278d 911 ref_file = git_path("%s", ref);
5bdd8d4a 912 if (missing)
68db31cc
SV
913 lock->force_write = 1;
914 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
915 lock->force_write = 1;
4bd18c43 916
5cc3cef9
JH
917 if (safe_create_leading_directories(ref_file)) {
918 last_errno = errno;
919 error("unable to create directory for %s", ref_file);
920 goto error_return;
921 }
4bd18c43 922
acd3b9ec 923 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 924 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
925
926 error_return:
927 unlock_ref(lock);
928 errno = last_errno;
929 return NULL;
4bd18c43
SP
930}
931
4431fcc4 932struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
95fc7512 933{
53cce84c 934 char refpath[PATH_MAX];
95fc7512 935 if (check_ref_format(ref))
4bd18c43 936 return NULL;
53cce84c 937 strcpy(refpath, mkpath("refs/%s", ref));
68db31cc 938 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
939}
940
68db31cc 941struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
4bd18c43 942{
5f7b202a 943 switch (check_ref_format(ref)) {
5f7b202a 944 default:
257f3020
JH
945 return NULL;
946 case 0:
947 case CHECK_REF_FORMAT_ONELEVEL:
5f7b202a
JH
948 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
949 }
c0277d15
JH
950}
951
26a063a1
JH
952static struct lock_file packlock;
953
c0277d15
JH
954static int repack_without_ref(const char *refname)
955{
956 struct ref_list *list, *packed_ref_list;
957 int fd;
958 int found = 0;
c0277d15
JH
959
960 packed_ref_list = get_packed_refs();
961 for (list = packed_ref_list; list; list = list->next) {
962 if (!strcmp(refname, list->name)) {
963 found = 1;
964 break;
965 }
966 }
967 if (!found)
968 return 0;
c0277d15
JH
969 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
970 if (fd < 0)
971 return error("cannot delete '%s' from packed refs", refname);
972
973 for (list = packed_ref_list; list; list = list->next) {
974 char line[PATH_MAX + 100];
975 int len;
976
977 if (!strcmp(refname, list->name))
978 continue;
979 len = snprintf(line, sizeof(line), "%s %s\n",
980 sha1_to_hex(list->sha1), list->name);
981 /* this should not happen but just being defensive */
982 if (len > sizeof(line))
983 die("too long a refname '%s'", list->name);
984 write_or_die(fd, line, len);
985 }
986 return commit_lock_file(&packlock);
987}
988
eca35a25 989int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
990{
991 struct ref_lock *lock;
eca35a25 992 int err, i = 0, ret = 0, flag = 0;
c0277d15 993
68db31cc 994 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
995 if (!lock)
996 return 1;
045a476f 997 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 998 /* loose */
eca35a25
MV
999 const char *path;
1000
1001 if (!(delopt & REF_NODEREF)) {
1002 i = strlen(lock->lk->filename) - 5; /* .lock */
1003 lock->lk->filename[i] = 0;
1004 path = lock->lk->filename;
1005 } else {
9db56f71 1006 path = git_path("%s", refname);
eca35a25 1007 }
691f1a28
AR
1008 err = unlink_or_warn(path);
1009 if (err && errno != ENOENT)
c0277d15 1010 ret = 1;
691f1a28 1011
eca35a25
MV
1012 if (!(delopt & REF_NODEREF))
1013 lock->lk->filename[i] = '.';
c0277d15
JH
1014 }
1015 /* removing the loose one could have resurrected an earlier
1016 * packed one. Also, if it was not loose we need to repack
1017 * without it.
1018 */
1019 ret |= repack_without_ref(refname);
1020
691f1a28 1021 unlink_or_warn(git_path("logs/%s", lock->ref_name));
c0277d15
JH
1022 invalidate_cached_refs();
1023 unlock_ref(lock);
1024 return ret;
4bd18c43
SP
1025}
1026
678d0f4c 1027int rename_ref(const char *oldref, const char *newref, const char *logmsg)
c976d415
LH
1028{
1029 static const char renamed_ref[] = "RENAMED-REF";
1030 unsigned char sha1[20], orig_sha1[20];
1031 int flag = 0, logmoved = 0;
1032 struct ref_lock *lock;
c976d415 1033 struct stat loginfo;
16c2bfbb 1034 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
eca35a25 1035 const char *symref = NULL;
c976d415 1036
450d4c0f 1037 if (log && S_ISLNK(loginfo.st_mode))
c976d415
LH
1038 return error("reflog for %s is a symlink", oldref);
1039
eca35a25
MV
1040 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1041 if (flag & REF_ISSYMREF)
fa58186c
MV
1042 return error("refname %s is a symbolic ref, renaming it is not supported",
1043 oldref);
eca35a25 1044 if (!symref)
c976d415
LH
1045 return error("refname %s not found", oldref);
1046
1047 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1048 return 1;
1049
1050 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1051 return 1;
1052
68db31cc 1053 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
c976d415
LH
1054 if (!lock)
1055 return error("unable to lock %s", renamed_ref);
1056 lock->force_write = 1;
678d0f4c 1057 if (write_ref_sha1(lock, orig_sha1, logmsg))
c976d415
LH
1058 return error("unable to save current sha1 in %s", renamed_ref);
1059
1060 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1061 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1062 oldref, strerror(errno));
1063
eca35a25 1064 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
c976d415
LH
1065 error("unable to delete old %s", oldref);
1066 goto rollback;
1067 }
1068
eca35a25 1069 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
c976d415
LH
1070 if (errno==EISDIR) {
1071 if (remove_empty_directories(git_path("%s", newref))) {
1072 error("Directory not empty: %s", newref);
1073 goto rollback;
1074 }
1075 } else {
1076 error("unable to delete existing %s", newref);
1077 goto rollback;
1078 }
1079 }
1080
1081 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1082 error("unable to create directory for %s", newref);
1083 goto rollback;
1084 }
1085
1086 retry:
1087 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
d9e74d57
JR
1088 if (errno==EISDIR || errno==ENOTDIR) {
1089 /*
1090 * rename(a, b) when b is an existing
1091 * directory ought to result in ISDIR, but
1092 * Solaris 5.8 gives ENOTDIR. Sheesh.
1093 */
c976d415
LH
1094 if (remove_empty_directories(git_path("logs/%s", newref))) {
1095 error("Directory not empty: logs/%s", newref);
1096 goto rollback;
1097 }
1098 goto retry;
1099 } else {
1100 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1101 newref, strerror(errno));
1102 goto rollback;
1103 }
1104 }
1105 logmoved = log;
1106
68db31cc 1107 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
c976d415
LH
1108 if (!lock) {
1109 error("unable to lock %s for update", newref);
1110 goto rollback;
1111 }
c976d415
LH
1112 lock->force_write = 1;
1113 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1114 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
c976d415
LH
1115 error("unable to write current sha1 into %s", newref);
1116 goto rollback;
1117 }
1118
1119 return 0;
1120
1121 rollback:
68db31cc 1122 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
c976d415
LH
1123 if (!lock) {
1124 error("unable to lock %s for rollback", oldref);
1125 goto rollbacklog;
1126 }
1127
1128 lock->force_write = 1;
1129 flag = log_all_ref_updates;
1130 log_all_ref_updates = 0;
1131 if (write_ref_sha1(lock, orig_sha1, NULL))
1132 error("unable to write current sha1 into %s", oldref);
1133 log_all_ref_updates = flag;
1134
1135 rollbacklog:
1136 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1137 error("unable to restore logfile %s from %s: %s",
1138 oldref, newref, strerror(errno));
1139 if (!logmoved && log &&
1140 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1141 error("unable to restore logfile %s from tmp-renamed-log: %s",
1142 oldref, strerror(errno));
1143
1144 return 1;
1145}
1146
435fc852 1147int close_ref(struct ref_lock *lock)
b531394d
BC
1148{
1149 if (close_lock_file(lock->lk))
1150 return -1;
1151 lock->lock_fd = -1;
1152 return 0;
1153}
1154
435fc852 1155int commit_ref(struct ref_lock *lock)
b531394d
BC
1156{
1157 if (commit_lock_file(lock->lk))
1158 return -1;
1159 lock->lock_fd = -1;
1160 return 0;
1161}
1162
e5f38ec3 1163void unlock_ref(struct ref_lock *lock)
4bd18c43 1164{
4ed7cd3a
BC
1165 /* Do not free lock->lk -- atexit() still looks at them */
1166 if (lock->lk)
1167 rollback_lock_file(lock->lk);
434cd0cd 1168 free(lock->ref_name);
1655707c 1169 free(lock->orig_ref_name);
4bd18c43
SP
1170 free(lock);
1171}
1172
0ec29a47
JH
1173/*
1174 * copy the reflog message msg to buf, which has been allocated sufficiently
1175 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1176 * because reflog file is one line per entry.
1177 */
1178static int copy_msg(char *buf, const char *msg)
1179{
1180 char *cp = buf;
1181 char c;
1182 int wasspace = 1;
1183
1184 *cp++ = '\t';
1185 while ((c = *msg++)) {
1186 if (wasspace && isspace(c))
1187 continue;
1188 wasspace = isspace(c);
1189 if (wasspace)
1190 c = ' ';
1191 *cp++ = c;
1192 }
1193 while (buf < cp && isspace(cp[-1]))
1194 cp--;
1195 *cp++ = '\n';
1196 return cp - buf;
1197}
1198
9a13f0b7
NP
1199static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1200 const unsigned char *new_sha1, const char *msg)
6de08ae6
SP
1201{
1202 int logfd, written, oflags = O_APPEND | O_WRONLY;
1203 unsigned maxlen, len;
8ac65937 1204 int msglen;
958a4789
AR
1205 char log_file[PATH_MAX];
1206 char *logrec;
ff4c8485 1207 const char *committer;
6de08ae6 1208
510c5a8e 1209 if (log_all_ref_updates < 0)
7d1864ce 1210 log_all_ref_updates = !is_bare_repository();
510c5a8e 1211
958a4789 1212 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
9a13f0b7 1213
4057deb5 1214 if (log_all_ref_updates &&
cc44c765
JH
1215 (!prefixcmp(ref_name, "refs/heads/") ||
1216 !prefixcmp(ref_name, "refs/remotes/") ||
bd104db1 1217 !strcmp(ref_name, "HEAD"))) {
9a13f0b7 1218 if (safe_create_leading_directories(log_file) < 0)
6de08ae6 1219 return error("unable to create directory for %s",
9a13f0b7 1220 log_file);
6de08ae6
SP
1221 oflags |= O_CREAT;
1222 }
1223
9a13f0b7 1224 logfd = open(log_file, oflags, 0666);
6de08ae6 1225 if (logfd < 0) {
1974bf62 1226 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1227 return 0;
3b463c3f
JH
1228
1229 if ((oflags & O_CREAT) && errno == EISDIR) {
9a13f0b7 1230 if (remove_empty_directories(log_file)) {
3b463c3f 1231 return error("There are still logs under '%s'",
9a13f0b7 1232 log_file);
3b463c3f 1233 }
9a13f0b7 1234 logfd = open(log_file, oflags, 0666);
3b463c3f
JH
1235 }
1236
1237 if (logfd < 0)
1238 return error("Unable to append to %s: %s",
9a13f0b7 1239 log_file, strerror(errno));
6de08ae6
SP
1240 }
1241
443b92b6
MK
1242 adjust_shared_perm(log_file);
1243
0ec29a47 1244 msglen = msg ? strlen(msg) : 0;
774751a8 1245 committer = git_committer_info(0);
8ac65937
JH
1246 maxlen = strlen(committer) + msglen + 100;
1247 logrec = xmalloc(maxlen);
1248 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1249 sha1_to_hex(old_sha1),
1250 sha1_to_hex(new_sha1),
8ac65937
JH
1251 committer);
1252 if (msglen)
0ec29a47 1253 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1254 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1255 free(logrec);
91c8d590 1256 if (close(logfd) != 0 || written != len)
9a13f0b7 1257 return error("Unable to append to %s", log_file);
6de08ae6
SP
1258 return 0;
1259}
1260
c3b0dec5
LT
1261static int is_branch(const char *refname)
1262{
1263 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1264}
1265
4bd18c43
SP
1266int write_ref_sha1(struct ref_lock *lock,
1267 const unsigned char *sha1, const char *logmsg)
1268{
1269 static char term = '\n';
c3b0dec5 1270 struct object *o;
4bd18c43
SP
1271
1272 if (!lock)
95fc7512 1273 return -1;
a89fccd2 1274 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1275 unlock_ref(lock);
1276 return 0;
95fc7512 1277 }
c3b0dec5
LT
1278 o = parse_object(sha1);
1279 if (!o) {
1280 error("Trying to write ref %s with nonexistant object %s",
1281 lock->ref_name, sha1_to_hex(sha1));
1282 unlock_ref(lock);
1283 return -1;
1284 }
1285 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1286 error("Trying to write non-commit object %s to branch %s",
1287 sha1_to_hex(sha1), lock->ref_name);
1288 unlock_ref(lock);
1289 return -1;
1290 }
93822c22
AW
1291 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1292 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1293 || close_ref(lock) < 0) {
c33d5174 1294 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1295 unlock_ref(lock);
1296 return -1;
1297 }
5e290ff7 1298 invalidate_cached_refs();
bd104db1
NP
1299 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1300 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1301 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1302 unlock_ref(lock);
1303 return -1;
1304 }
605fac8b
NP
1305 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1306 /*
1307 * Special hack: If a branch is updated directly and HEAD
1308 * points to it (may happen on the remote side of a push
1309 * for example) then logically the HEAD reflog should be
1310 * updated too.
1311 * A generic solution implies reverse symref information,
1312 * but finding all symrefs pointing to the given branch
1313 * would be rather costly for this rare event (the direct
1314 * update of a branch) to be worth it. So let's cheat and
1315 * check with HEAD only which should cover 99% of all usage
1316 * scenarios (even 100% of the default ones).
1317 */
1318 unsigned char head_sha1[20];
1319 int head_flag;
1320 const char *head_ref;
1321 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1322 if (head_ref && (head_flag & REF_ISSYMREF) &&
1323 !strcmp(head_ref, lock->ref_name))
1324 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1325 }
b531394d 1326 if (commit_ref(lock)) {
434cd0cd 1327 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1328 unlock_ref(lock);
1329 return -1;
1330 }
4bd18c43
SP
1331 unlock_ref(lock);
1332 return 0;
95fc7512 1333}
d556fae2 1334
8b5157e4
NP
1335int create_symref(const char *ref_target, const char *refs_heads_master,
1336 const char *logmsg)
41b625b0
NP
1337{
1338 const char *lockpath;
1339 char ref[1000];
1340 int fd, len, written;
a4f34cbb 1341 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1342 unsigned char old_sha1[20], new_sha1[20];
1343
1344 if (logmsg && read_ref(ref_target, old_sha1))
1345 hashclr(old_sha1);
41b625b0 1346
d48744d1
JH
1347 if (safe_create_leading_directories(git_HEAD) < 0)
1348 return error("unable to create directory for %s", git_HEAD);
1349
41b625b0
NP
1350#ifndef NO_SYMLINK_HEAD
1351 if (prefer_symlink_refs) {
1352 unlink(git_HEAD);
1353 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1354 goto done;
41b625b0
NP
1355 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1356 }
1357#endif
1358
1359 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1360 if (sizeof(ref) <= len) {
1361 error("refname too long: %s", refs_heads_master);
47fc52e2 1362 goto error_free_return;
41b625b0
NP
1363 }
1364 lockpath = mkpath("%s.lock", git_HEAD);
1365 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1366 if (fd < 0) {
1367 error("Unable to open %s for writing", lockpath);
47fc52e2 1368 goto error_free_return;
41b625b0
NP
1369 }
1370 written = write_in_full(fd, ref, len);
91c8d590 1371 if (close(fd) != 0 || written != len) {
41b625b0 1372 error("Unable to write to %s", lockpath);
47fc52e2 1373 goto error_unlink_return;
41b625b0
NP
1374 }
1375 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1376 error("Unable to create %s", git_HEAD);
47fc52e2 1377 goto error_unlink_return;
41b625b0
NP
1378 }
1379 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1380 error("Unable to fix permissions on %s", lockpath);
47fc52e2 1381 error_unlink_return:
691f1a28 1382 unlink_or_warn(lockpath);
47fc52e2
JH
1383 error_free_return:
1384 free(git_HEAD);
1385 return -1;
41b625b0 1386 }
8b5157e4 1387
ee96d11b 1388#ifndef NO_SYMLINK_HEAD
8b5157e4 1389 done:
ee96d11b 1390#endif
8b5157e4
NP
1391 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1392 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1393
47fc52e2 1394 free(git_HEAD);
41b625b0
NP
1395 return 0;
1396}
1397
16d7cc90
JH
1398static char *ref_msg(const char *line, const char *endp)
1399{
1400 const char *ep;
16d7cc90 1401 line += 82;
182af834
PH
1402 ep = memchr(line, '\n', endp - line);
1403 if (!ep)
1404 ep = endp;
1405 return xmemdupz(line, ep - line);
16d7cc90
JH
1406}
1407
1408int 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 1409{
e5229042 1410 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1411 char *tz_c;
e29cb53a 1412 int logfd, tz, reccnt = 0;
d556fae2
SP
1413 struct stat st;
1414 unsigned long date;
e5229042 1415 unsigned char logged_sha1[20];
cb48cb58 1416 void *log_mapped;
dc49cd76 1417 size_t mapsz;
d556fae2
SP
1418
1419 logfile = git_path("logs/%s", ref);
1420 logfd = open(logfile, O_RDONLY, 0);
1421 if (logfd < 0)
d824cbba 1422 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
1423 fstat(logfd, &st);
1424 if (!st.st_size)
1425 die("Log %s is empty.", logfile);
dc49cd76
SP
1426 mapsz = xsize_t(st.st_size);
1427 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1428 logdata = log_mapped;
d556fae2
SP
1429 close(logfd);
1430
e5229042 1431 lastrec = NULL;
d556fae2
SP
1432 rec = logend = logdata + st.st_size;
1433 while (logdata < rec) {
e29cb53a 1434 reccnt++;
d556fae2
SP
1435 if (logdata < rec && *(rec-1) == '\n')
1436 rec--;
e5229042
SP
1437 lastgt = NULL;
1438 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1439 rec--;
e5229042
SP
1440 if (*rec == '>')
1441 lastgt = rec;
1442 }
1443 if (!lastgt)
d556fae2 1444 die("Log %s is corrupt.", logfile);
e5229042 1445 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1446 if (date <= at_time || cnt == 0) {
76a44c5c 1447 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1448 if (msg)
1449 *msg = ref_msg(rec, logend);
1450 if (cutoff_time)
1451 *cutoff_time = date;
1452 if (cutoff_tz)
1453 *cutoff_tz = tz;
1454 if (cutoff_cnt)
76a44c5c 1455 *cutoff_cnt = reccnt - 1;
e5229042
SP
1456 if (lastrec) {
1457 if (get_sha1_hex(lastrec, logged_sha1))
1458 die("Log %s is corrupt.", logfile);
1459 if (get_sha1_hex(rec + 41, sha1))
1460 die("Log %s is corrupt.", logfile);
a89fccd2 1461 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1462 warning("Log %s has gap after %s.",
73013afd 1463 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1464 }
e5f38ec3
JH
1465 }
1466 else if (date == at_time) {
e5229042
SP
1467 if (get_sha1_hex(rec + 41, sha1))
1468 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1469 }
1470 else {
e5229042
SP
1471 if (get_sha1_hex(rec + 41, logged_sha1))
1472 die("Log %s is corrupt.", logfile);
a89fccd2 1473 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1474 warning("Log %s unexpectedly ended on %s.",
73013afd 1475 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1476 }
1477 }
dc49cd76 1478 munmap(log_mapped, mapsz);
d556fae2
SP
1479 return 0;
1480 }
e5229042 1481 lastrec = rec;
ab2a1a32
JH
1482 if (cnt > 0)
1483 cnt--;
d556fae2
SP
1484 }
1485
e5229042
SP
1486 rec = logdata;
1487 while (rec < logend && *rec != '>' && *rec != '\n')
1488 rec++;
1489 if (rec == logend || *rec == '\n')
d556fae2 1490 die("Log %s is corrupt.", logfile);
e5229042 1491 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1492 tz = strtoul(tz_c, NULL, 10);
1493 if (get_sha1_hex(logdata, sha1))
1494 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1495 if (is_null_sha1(sha1)) {
1496 if (get_sha1_hex(logdata + 41, sha1))
1497 die("Log %s is corrupt.", logfile);
1498 }
16d7cc90
JH
1499 if (msg)
1500 *msg = ref_msg(logdata, logend);
dc49cd76 1501 munmap(log_mapped, mapsz);
16d7cc90
JH
1502
1503 if (cutoff_time)
1504 *cutoff_time = date;
1505 if (cutoff_tz)
1506 *cutoff_tz = tz;
1507 if (cutoff_cnt)
1508 *cutoff_cnt = reccnt;
1509 return 1;
d556fae2 1510}
2ff81662 1511
101d15e0 1512int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
1513{
1514 const char *logfile;
1515 FILE *logfp;
1516 char buf[1024];
2266bf27 1517 int ret = 0;
2ff81662
JH
1518
1519 logfile = git_path("logs/%s", ref);
1520 logfp = fopen(logfile, "r");
1521 if (!logfp)
883d60fa 1522 return -1;
101d15e0
JH
1523
1524 if (ofs) {
1525 struct stat statbuf;
1526 if (fstat(fileno(logfp), &statbuf) ||
1527 statbuf.st_size < ofs ||
1528 fseek(logfp, -ofs, SEEK_END) ||
9d33f7c2
BC
1529 fgets(buf, sizeof(buf), logfp)) {
1530 fclose(logfp);
101d15e0 1531 return -1;
9d33f7c2 1532 }
101d15e0
JH
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
6e7b3309 1684char *shorten_unambiguous_ref(const char *ref, int strict)
7c2b3029
JK
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;
6e7b3309 1721 int rules_to_fail = i;
7c2b3029
JK
1722 int short_name_len;
1723
1724 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1725 continue;
1726
1727 short_name_len = strlen(short_name);
1728
6e7b3309
BW
1729 /*
1730 * in strict mode, all (except the matched one) rules
1731 * must fail to resolve to a valid non-ambiguous ref
1732 */
1733 if (strict)
1734 rules_to_fail = nr_rules;
1735
7c2b3029
JK
1736 /*
1737 * check if the short name resolves to a valid ref,
1738 * but use only rules prior to the matched one
1739 */
6e7b3309 1740 for (j = 0; j < rules_to_fail; j++) {
7c2b3029
JK
1741 const char *rule = ref_rev_parse_rules[j];
1742 unsigned char short_objectname[20];
1743 char refname[PATH_MAX];
1744
6e7b3309
BW
1745 /* skip matched rule */
1746 if (i == j)
1747 continue;
1748
7c2b3029
JK
1749 /*
1750 * the short name is ambiguous, if it resolves
1751 * (with this previous rule) to a valid ref
1752 * read_ref() returns 0 on success
1753 */
1754 mksnpath(refname, sizeof(refname),
1755 rule, short_name_len, short_name);
1756 if (!read_ref(refname, short_objectname))
1757 break;
1758 }
1759
1760 /*
1761 * short name is non-ambiguous if all previous rules
1762 * haven't resolved to a valid ref
1763 */
6e7b3309 1764 if (j == rules_to_fail)
7c2b3029
JK
1765 return short_name;
1766 }
1767
1768 free(short_name);
1769 return xstrdup(ref);
1770}