Documentation: alter checkout --orphan description
[git/git.git] / refs.c
CommitLineData
95fc7512 1#include "cache.h"
85023577 2#include "refs.h"
cf0adba7
JH
3#include "object.h"
4#include "tag.h"
7155b727 5#include "dir.h"
95fc7512 6
f4204ab9
JH
7/* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8#define REF_KNOWS_PEELED 04
e01de1c9 9#define REF_BROKEN 010
f4204ab9 10
e1e22e37
LT
11struct ref_list {
12 struct ref_list *next;
f4204ab9 13 unsigned char flag; /* ISSYMREF? ISPACKED? */
e1e22e37 14 unsigned char sha1[20];
f4204ab9 15 unsigned char peeled[20];
e1e22e37
LT
16 char name[FLEX_ARRAY];
17};
18
f4204ab9 19static const char *parse_ref_line(char *line, unsigned char *sha1)
e1e22e37
LT
20{
21 /*
22 * 42: the answer to everything.
23 *
24 * In this case, it happens to be the answer to
25 * 40 (length of sha1 hex representation)
26 * +1 (space in between hex and name)
27 * +1 (newline at the end of the line)
28 */
29 int len = strlen(line) - 42;
30
31 if (len <= 0)
32 return NULL;
33 if (get_sha1_hex(line, sha1) < 0)
34 return NULL;
35 if (!isspace(line[40]))
36 return NULL;
37 line += 41;
f4204ab9
JH
38 if (isspace(*line))
39 return NULL;
e1e22e37
LT
40 if (line[len] != '\n')
41 return NULL;
42 line[len] = 0;
cf0adba7 43
e1e22e37
LT
44 return line;
45}
46
8da19775 47static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
f4204ab9
JH
48 int flag, struct ref_list *list,
49 struct ref_list **new_entry)
e1e22e37
LT
50{
51 int len;
c774aab9 52 struct ref_list *entry;
e1e22e37
LT
53
54 /* Allocate it and add it in.. */
55 len = strlen(name) + 1;
56 entry = xmalloc(sizeof(struct ref_list) + len);
57 hashcpy(entry->sha1, sha1);
f4204ab9 58 hashclr(entry->peeled);
e1e22e37 59 memcpy(entry->name, name, len);
8da19775 60 entry->flag = flag;
c774aab9 61 entry->next = list;
f4204ab9
JH
62 if (new_entry)
63 *new_entry = entry;
c774aab9
JP
64 return entry;
65}
66
67/* merge sort the ref list */
68static struct ref_list *sort_ref_list(struct ref_list *list)
69{
70 int psize, qsize, last_merge_count, cmp;
71 struct ref_list *p, *q, *l, *e;
72 struct ref_list *new_list = list;
73 int k = 1;
74 int merge_count = 0;
75
76 if (!list)
77 return list;
78
79 do {
80 last_merge_count = merge_count;
81 merge_count = 0;
82
83 psize = 0;
84
85 p = new_list;
86 q = new_list;
87 new_list = NULL;
88 l = NULL;
89
90 while (p) {
91 merge_count++;
92
93 while (psize < k && q->next) {
94 q = q->next;
95 psize++;
96 }
97 qsize = k;
98
99 while ((psize > 0) || (qsize > 0 && q)) {
100 if (qsize == 0 || !q) {
101 e = p;
102 p = p->next;
103 psize--;
104 } else if (psize == 0) {
105 e = q;
106 q = q->next;
107 qsize--;
108 } else {
109 cmp = strcmp(q->name, p->name);
110 if (cmp < 0) {
111 e = q;
112 q = q->next;
113 qsize--;
114 } else if (cmp > 0) {
115 e = p;
116 p = p->next;
117 psize--;
118 } else {
119 if (hashcmp(q->sha1, p->sha1))
120 die("Duplicated ref, and SHA1s don't match: %s",
121 q->name);
122 warning("Duplicated ref: %s", q->name);
123 e = q;
124 q = q->next;
125 qsize--;
126 free(e);
127 e = p;
128 p = p->next;
129 psize--;
130 }
131 }
132
133 e->next = NULL;
134
135 if (l)
136 l->next = e;
137 if (!new_list)
138 new_list = e;
139 l = e;
140 }
141
142 p = q;
143 };
144
145 k = k * 2;
146 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
147
148 return new_list;
e1e22e37
LT
149}
150
5e290ff7
JH
151/*
152 * Future: need to be in "struct repository"
153 * when doing a full libification.
154 */
4175e9e3 155static struct cached_refs {
5e290ff7
JH
156 char did_loose;
157 char did_packed;
158 struct ref_list *loose;
159 struct ref_list *packed;
160} cached_refs;
0ae91be0 161static struct ref_list *current_ref;
5e290ff7 162
e142a3c6
DB
163static struct ref_list *extra_refs;
164
5e290ff7
JH
165static void free_ref_list(struct ref_list *list)
166{
167 struct ref_list *next;
168 for ( ; list; list = next) {
169 next = list->next;
170 free(list);
171 }
172}
173
174static void invalidate_cached_refs(void)
e1e22e37 175{
5e290ff7
JH
176 struct cached_refs *ca = &cached_refs;
177
178 if (ca->did_loose && ca->loose)
179 free_ref_list(ca->loose);
180 if (ca->did_packed && ca->packed)
181 free_ref_list(ca->packed);
182 ca->loose = ca->packed = NULL;
183 ca->did_loose = ca->did_packed = 0;
184}
e1e22e37 185
f4204ab9
JH
186static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
187{
188 struct ref_list *list = NULL;
189 struct ref_list *last = NULL;
190 char refline[PATH_MAX];
191 int flag = REF_ISPACKED;
192
193 while (fgets(refline, sizeof(refline), f)) {
194 unsigned char sha1[20];
195 const char *name;
196 static const char header[] = "# pack-refs with:";
197
198 if (!strncmp(refline, header, sizeof(header)-1)) {
199 const char *traits = refline + sizeof(header) - 1;
200 if (strstr(traits, " peeled "))
201 flag |= REF_KNOWS_PEELED;
202 /* perhaps other traits later as well */
203 continue;
204 }
205
206 name = parse_ref_line(refline, sha1);
207 if (name) {
208 list = add_ref(name, sha1, flag, list, &last);
209 continue;
210 }
211 if (last &&
212 refline[0] == '^' &&
213 strlen(refline) == 42 &&
214 refline[41] == '\n' &&
215 !get_sha1_hex(refline + 1, sha1))
216 hashcpy(last->peeled, sha1);
217 }
c774aab9 218 cached_refs->packed = sort_ref_list(list);
f4204ab9
JH
219}
220
e142a3c6
DB
221void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
222{
223 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
224}
225
226void clear_extra_refs(void)
227{
228 free_ref_list(extra_refs);
229 extra_refs = NULL;
230}
231
5e290ff7
JH
232static struct ref_list *get_packed_refs(void)
233{
234 if (!cached_refs.did_packed) {
e1e22e37 235 FILE *f = fopen(git_path("packed-refs"), "r");
f4204ab9 236 cached_refs.packed = NULL;
e1e22e37 237 if (f) {
f4204ab9 238 read_packed_refs(f, &cached_refs);
e1e22e37 239 fclose(f);
e1e22e37 240 }
5e290ff7 241 cached_refs.did_packed = 1;
e1e22e37 242 }
5e290ff7 243 return cached_refs.packed;
e1e22e37
LT
244}
245
246static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
247{
248 DIR *dir = opendir(git_path("%s", base));
249
250 if (dir) {
251 struct dirent *de;
252 int baselen = strlen(base);
ed378ec7 253 char *ref = xmalloc(baselen + 257);
e1e22e37 254
ed378ec7 255 memcpy(ref, base, baselen);
e1e22e37 256 if (baselen && base[baselen-1] != '/')
ed378ec7 257 ref[baselen++] = '/';
e1e22e37
LT
258
259 while ((de = readdir(dir)) != NULL) {
260 unsigned char sha1[20];
261 struct stat st;
8da19775 262 int flag;
e1e22e37
LT
263 int namelen;
264
265 if (de->d_name[0] == '.')
266 continue;
267 namelen = strlen(de->d_name);
268 if (namelen > 255)
269 continue;
270 if (has_extension(de->d_name, ".lock"))
271 continue;
ed378ec7
LT
272 memcpy(ref + baselen, de->d_name, namelen+1);
273 if (stat(git_path("%s", ref), &st) < 0)
e1e22e37
LT
274 continue;
275 if (S_ISDIR(st.st_mode)) {
ed378ec7 276 list = get_ref_dir(ref, list);
e1e22e37
LT
277 continue;
278 }
e01de1c9 279 if (!resolve_ref(ref, sha1, 1, &flag)) {
f8948e2f 280 hashclr(sha1);
e01de1c9
JH
281 flag |= REF_BROKEN;
282 }
f4204ab9 283 list = add_ref(ref, sha1, flag, list, NULL);
e1e22e37 284 }
ed378ec7 285 free(ref);
e1e22e37
LT
286 closedir(dir);
287 }
c774aab9 288 return sort_ref_list(list);
e1e22e37
LT
289}
290
f8948e2f 291struct warn_if_dangling_data {
3cf6134a 292 FILE *fp;
f8948e2f
JH
293 const char *refname;
294 const char *msg_fmt;
295};
296
297static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
298 int flags, void *cb_data)
299{
300 struct warn_if_dangling_data *d = cb_data;
301 const char *resolves_to;
302 unsigned char junk[20];
303
304 if (!(flags & REF_ISSYMREF))
305 return 0;
306
307 resolves_to = resolve_ref(refname, junk, 0, NULL);
308 if (!resolves_to || strcmp(resolves_to, d->refname))
309 return 0;
310
3cf6134a 311 fprintf(d->fp, d->msg_fmt, refname);
f8948e2f
JH
312 return 0;
313}
314
3cf6134a 315void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
f8948e2f 316{
3cf6134a 317 struct warn_if_dangling_data data = { fp, refname, msg_fmt };
f8948e2f
JH
318 for_each_rawref(warn_if_dangling_symref, &data);
319}
320
e1e22e37
LT
321static struct ref_list *get_loose_refs(void)
322{
5e290ff7
JH
323 if (!cached_refs.did_loose) {
324 cached_refs.loose = get_ref_dir("refs", NULL);
325 cached_refs.did_loose = 1;
e1e22e37 326 }
5e290ff7 327 return cached_refs.loose;
e1e22e37
LT
328}
329
ca8db142
LT
330/* We allow "recursive" symbolic refs. Only within reason, though */
331#define MAXDEPTH 5
0ebde32c
LT
332#define MAXREFLEN (1024)
333
334static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
335{
336 FILE *f;
337 struct cached_refs refs;
338 struct ref_list *ref;
339 int retval;
340
341 strcpy(name + pathlen, "packed-refs");
342 f = fopen(name, "r");
343 if (!f)
344 return -1;
345 read_packed_refs(f, &refs);
346 fclose(f);
347 ref = refs.packed;
348 retval = -1;
349 while (ref) {
350 if (!strcmp(ref->name, refname)) {
351 retval = 0;
352 memcpy(result, ref->sha1, 20);
353 break;
354 }
355 ref = ref->next;
356 }
357 free_ref_list(refs.packed);
358 return retval;
359}
360
361static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
362{
363 int fd, len = strlen(refname);
364 char buffer[128], *p;
365
366 if (recursion > MAXDEPTH || len > MAXREFLEN)
367 return -1;
368 memcpy(name + pathlen, refname, len+1);
369 fd = open(name, O_RDONLY);
370 if (fd < 0)
371 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
372
373 len = read(fd, buffer, sizeof(buffer)-1);
374 close(fd);
375 if (len < 0)
376 return -1;
377 while (len && isspace(buffer[len-1]))
378 len--;
379 buffer[len] = 0;
380
381 /* Was it a detached head or an old-fashioned symlink? */
382 if (!get_sha1_hex(buffer, result))
383 return 0;
384
385 /* Symref? */
386 if (strncmp(buffer, "ref:", 4))
387 return -1;
388 p = buffer + 4;
389 while (isspace(*p))
390 p++;
391
392 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
393}
394
395int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
396{
397 int len = strlen(path), retval;
398 char *gitdir;
842abf06 399 const char *tmp;
0ebde32c
LT
400
401 while (len && path[len-1] == '/')
402 len--;
403 if (!len)
404 return -1;
405 gitdir = xmalloc(len + MAXREFLEN + 8);
406 memcpy(gitdir, path, len);
842abf06
LH
407 memcpy(gitdir + len, "/.git", 6);
408 len += 5;
409
410 tmp = read_gitfile_gently(gitdir);
411 if (tmp) {
412 free(gitdir);
413 len = strlen(tmp);
414 gitdir = xmalloc(len + MAXREFLEN + 3);
415 memcpy(gitdir, tmp, len);
416 }
417 gitdir[len] = '/';
418 gitdir[++len] = '\0';
419 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
0ebde32c
LT
420 free(gitdir);
421 return retval;
422}
ca8db142 423
4886b89f
CC
424/*
425 * If the "reading" argument is set, this function finds out what _object_
426 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
427 * has to exist, and if it is symbolic, it has to point at an existing ref,
428 * because the "read" goes through the symref to the ref it points at.
429 *
430 * The access that is not "reading" may often be "writing", but does not
431 * have to; it can be merely checking _where it leads to_. If it is a
432 * prelude to "writing" to the ref, a write to a symref that points at
433 * yet-to-be-born ref will create the real ref pointed by the symref.
434 * reading=0 allows the caller to check where such a symref leads to.
435 */
8da19775 436const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
8a65ff76 437{
0104ca09
HO
438 int depth = MAXDEPTH;
439 ssize_t len;
a876ed83 440 char buffer[256];
ed378ec7 441 static char ref_buffer[256];
ca8db142 442
8da19775
JH
443 if (flag)
444 *flag = 0;
445
a876ed83 446 for (;;) {
958a4789 447 char path[PATH_MAX];
a876ed83
JH
448 struct stat st;
449 char *buf;
450 int fd;
8a65ff76 451
a876ed83
JH
452 if (--depth < 0)
453 return NULL;
ca8db142 454
958a4789 455 git_snpath(path, sizeof(path), "%s", ref);
4886b89f 456 /* Special case: non-existing file. */
a876ed83 457 if (lstat(path, &st) < 0) {
434cd0cd
LT
458 struct ref_list *list = get_packed_refs();
459 while (list) {
f4204ab9 460 if (!strcmp(ref, list->name)) {
434cd0cd 461 hashcpy(sha1, list->sha1);
8da19775
JH
462 if (flag)
463 *flag |= REF_ISPACKED;
434cd0cd
LT
464 return ref;
465 }
466 list = list->next;
467 }
a876ed83
JH
468 if (reading || errno != ENOENT)
469 return NULL;
e702496e 470 hashclr(sha1);
ed378ec7 471 return ref;
a876ed83 472 }
ca8db142 473
a876ed83
JH
474 /* Follow "normalized" - ie "refs/.." symlinks by hand */
475 if (S_ISLNK(st.st_mode)) {
476 len = readlink(path, buffer, sizeof(buffer)-1);
477 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
ed378ec7
LT
478 buffer[len] = 0;
479 strcpy(ref_buffer, buffer);
480 ref = ref_buffer;
8da19775
JH
481 if (flag)
482 *flag |= REF_ISSYMREF;
a876ed83
JH
483 continue;
484 }
ca8db142 485 }
a876ed83 486
7a21632f
DS
487 /* Is it a directory? */
488 if (S_ISDIR(st.st_mode)) {
489 errno = EISDIR;
490 return NULL;
491 }
492
a876ed83
JH
493 /*
494 * Anything else, just open it and try to use it as
495 * a ref
496 */
497 fd = open(path, O_RDONLY);
498 if (fd < 0)
499 return NULL;
93d26e4c 500 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83
JH
501 close(fd);
502
503 /*
504 * Is it a symbolic ref?
505 */
506 if (len < 4 || memcmp("ref:", buffer, 4))
507 break;
508 buf = buffer + 4;
509 len -= 4;
510 while (len && isspace(*buf))
511 buf++, len--;
512 while (len && isspace(buf[len-1]))
ed378ec7
LT
513 len--;
514 buf[len] = 0;
515 memcpy(ref_buffer, buf, len + 1);
516 ref = ref_buffer;
8da19775
JH
517 if (flag)
518 *flag |= REF_ISSYMREF;
8a65ff76 519 }
a876ed83
JH
520 if (len < 40 || get_sha1_hex(buffer, sha1))
521 return NULL;
ed378ec7 522 return ref;
a876ed83
JH
523}
524
d08bae7e
IL
525/* The argument to filter_refs */
526struct ref_filter {
527 const char *pattern;
528 each_ref_fn *fn;
529 void *cb_data;
530};
531
ed378ec7 532int read_ref(const char *ref, unsigned char *sha1)
a876ed83 533{
8da19775 534 if (resolve_ref(ref, sha1, 1, NULL))
a876ed83
JH
535 return 0;
536 return -1;
8a65ff76
LT
537}
538
f8948e2f 539#define DO_FOR_EACH_INCLUDE_BROKEN 01
ef06b918 540static int do_one_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 541 int flags, void *cb_data, struct ref_list *entry)
ef06b918
JH
542{
543 if (strncmp(base, entry->name, trim))
544 return 0;
e01de1c9 545
f8948e2f 546 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
e01de1c9
JH
547 if (entry->flag & REF_BROKEN)
548 return 0; /* ignore dangling symref */
f8948e2f
JH
549 if (!has_sha1_file(entry->sha1)) {
550 error("%s does not point to a valid object!", entry->name);
551 return 0;
552 }
ef06b918 553 }
0ae91be0 554 current_ref = entry;
ef06b918
JH
555 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
556}
557
d08bae7e
IL
558static int filter_refs(const char *ref, const unsigned char *sha, int flags,
559 void *data)
560{
561 struct ref_filter *filter = (struct ref_filter *)data;
562 if (fnmatch(filter->pattern, ref, 0))
563 return 0;
564 return filter->fn(ref, sha, flags, filter->cb_data);
565}
566
cf0adba7
JH
567int peel_ref(const char *ref, unsigned char *sha1)
568{
569 int flag;
570 unsigned char base[20];
571 struct object *o;
572
0ae91be0
SP
573 if (current_ref && (current_ref->name == ref
574 || !strcmp(current_ref->name, ref))) {
575 if (current_ref->flag & REF_KNOWS_PEELED) {
576 hashcpy(sha1, current_ref->peeled);
577 return 0;
578 }
579 hashcpy(base, current_ref->sha1);
580 goto fallback;
581 }
582
cf0adba7
JH
583 if (!resolve_ref(ref, base, 1, &flag))
584 return -1;
585
586 if ((flag & REF_ISPACKED)) {
587 struct ref_list *list = get_packed_refs();
cf0adba7
JH
588
589 while (list) {
f4204ab9
JH
590 if (!strcmp(list->name, ref)) {
591 if (list->flag & REF_KNOWS_PEELED) {
592 hashcpy(sha1, list->peeled);
593 return 0;
594 }
595 /* older pack-refs did not leave peeled ones */
596 break;
cf0adba7
JH
597 }
598 list = list->next;
599 }
cf0adba7
JH
600 }
601
0ae91be0 602fallback:
cf0adba7 603 o = parse_object(base);
8c87dc77 604 if (o && o->type == OBJ_TAG) {
cf0adba7
JH
605 o = deref_tag(o, ref, 0);
606 if (o) {
607 hashcpy(sha1, o->sha1);
608 return 0;
609 }
610 }
611 return -1;
612}
613
8da19775 614static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
f8948e2f 615 int flags, void *cb_data)
8a65ff76 616{
0ae91be0 617 int retval = 0;
e1e22e37
LT
618 struct ref_list *packed = get_packed_refs();
619 struct ref_list *loose = get_loose_refs();
8a65ff76 620
e142a3c6
DB
621 struct ref_list *extra;
622
623 for (extra = extra_refs; extra; extra = extra->next)
f8948e2f 624 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
e142a3c6 625
e1e22e37
LT
626 while (packed && loose) {
627 struct ref_list *entry;
628 int cmp = strcmp(packed->name, loose->name);
629 if (!cmp) {
630 packed = packed->next;
631 continue;
6cada6a9 632 }
e1e22e37
LT
633 if (cmp > 0) {
634 entry = loose;
635 loose = loose->next;
636 } else {
637 entry = packed;
638 packed = packed->next;
639 }
f8948e2f 640 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
e1e22e37 641 if (retval)
0ae91be0 642 goto end_each;
e1e22e37 643 }
8a65ff76 644
ef06b918 645 for (packed = packed ? packed : loose; packed; packed = packed->next) {
f8948e2f 646 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
ef06b918 647 if (retval)
0ae91be0 648 goto end_each;
8a65ff76 649 }
0ae91be0
SP
650
651end_each:
652 current_ref = NULL;
653 return retval;
8a65ff76
LT
654}
655
cb5d709f 656int head_ref(each_ref_fn fn, void *cb_data)
723c31fe
LT
657{
658 unsigned char sha1[20];
8da19775
JH
659 int flag;
660
661 if (resolve_ref("HEAD", sha1, 1, &flag))
662 return fn("HEAD", sha1, flag, cb_data);
2f34ba32 663 return 0;
723c31fe
LT
664}
665
cb5d709f 666int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 667{
f8948e2f 668 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
a62be77f
SE
669}
670
2a8177b6
CC
671int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
672{
673 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
674}
675
cb5d709f 676int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 677{
2a8177b6 678 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
679}
680
cb5d709f 681int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 682{
2a8177b6 683 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
684}
685
cb5d709f 686int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 687{
2a8177b6 688 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
689}
690
29268700
CC
691int for_each_replace_ref(each_ref_fn fn, void *cb_data)
692{
693 return do_for_each_ref("refs/replace/", fn, 13, 0, cb_data);
694}
695
b09fe971
IL
696int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
697 const char *prefix, void *cb_data)
d08bae7e
IL
698{
699 struct strbuf real_pattern = STRBUF_INIT;
700 struct ref_filter filter;
d08bae7e
IL
701 int ret;
702
b09fe971 703 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 704 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
705 else if (prefix)
706 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
707 strbuf_addstr(&real_pattern, pattern);
708
894a9d33 709 if (!has_glob_specials(pattern)) {
9517e6b8 710 /* Append implied '/' '*' if not present. */
d08bae7e
IL
711 if (real_pattern.buf[real_pattern.len - 1] != '/')
712 strbuf_addch(&real_pattern, '/');
713 /* No need to check for '*', there is none. */
714 strbuf_addch(&real_pattern, '*');
715 }
716
717 filter.pattern = real_pattern.buf;
718 filter.fn = fn;
719 filter.cb_data = cb_data;
720 ret = for_each_ref(filter_refs, &filter);
721
722 strbuf_release(&real_pattern);
723 return ret;
724}
725
b09fe971
IL
726int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
727{
728 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
729}
730
f8948e2f
JH
731int for_each_rawref(each_ref_fn fn, void *cb_data)
732{
733 return do_for_each_ref("refs/", fn, 0,
734 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
735}
736
03feddd6
JH
737/*
738 * Make sure "ref" is something reasonable to have under ".git/refs/";
739 * We do not like it if:
740 *
741 * - any path component of it begins with ".", or
742 * - it has double dots "..", or
743 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
744 * - it ends with a "/".
3e262b95 745 * - it ends with ".lock"
a4c2e699 746 * - it contains a "\" (backslash)
03feddd6
JH
747 */
748
749static inline int bad_ref_char(int ch)
750{
8558fd9e 751 if (((unsigned) ch) <= ' ' ||
a4c2e699 752 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
8558fd9e
DB
753 return 1;
754 /* 2.13 Pattern Matching Notation */
755 if (ch == '?' || ch == '[') /* Unsupported */
756 return 1;
757 if (ch == '*') /* Supported at the end */
758 return 2;
759 return 0;
03feddd6
JH
760}
761
95fc7512
DB
762int check_ref_format(const char *ref)
763{
cbdffe40 764 int ch, level, bad_type, last;
abd2bde7 765 int ret = CHECK_REF_FORMAT_OK;
03feddd6
JH
766 const char *cp = ref;
767
768 level = 0;
769 while (1) {
770 while ((ch = *cp++) == '/')
771 ; /* tolerate duplicated slashes */
772 if (!ch)
5f7b202a
JH
773 /* should not end with slashes */
774 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
775
776 /* we are at the beginning of the path component */
8558fd9e 777 if (ch == '.')
5f7b202a 778 return CHECK_REF_FORMAT_ERROR;
8558fd9e
DB
779 bad_type = bad_ref_char(ch);
780 if (bad_type) {
abd2bde7
DB
781 if (bad_type == 2 && (!*cp || *cp == '/') &&
782 ret == CHECK_REF_FORMAT_OK)
783 ret = CHECK_REF_FORMAT_WILDCARD;
784 else
785 return CHECK_REF_FORMAT_ERROR;
8558fd9e 786 }
03feddd6 787
cbdffe40 788 last = ch;
03feddd6
JH
789 /* scan the rest of the path component */
790 while ((ch = *cp++) != 0) {
8558fd9e 791 bad_type = bad_ref_char(ch);
cbdffe40 792 if (bad_type)
08fbdb30 793 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
794 if (ch == '/')
795 break;
cbdffe40
JH
796 if (last == '.' && ch == '.')
797 return CHECK_REF_FORMAT_ERROR;
798 if (last == '@' && ch == '{')
5f7b202a 799 return CHECK_REF_FORMAT_ERROR;
cbdffe40 800 last = ch;
03feddd6
JH
801 }
802 level++;
803 if (!ch) {
cbdffe40
JH
804 if (ref <= cp - 2 && cp[-2] == '.')
805 return CHECK_REF_FORMAT_ERROR;
03feddd6 806 if (level < 2)
5f7b202a 807 return CHECK_REF_FORMAT_ONELEVEL;
3e262b95
SP
808 if (has_extension(ref, ".lock"))
809 return CHECK_REF_FORMAT_ERROR;
abd2bde7 810 return ret;
03feddd6
JH
811 }
812 }
95fc7512
DB
813}
814
4577e483 815const char *prettify_refname(const char *name)
a9c37a72 816{
a9c37a72
DB
817 return name + (
818 !prefixcmp(name, "refs/heads/") ? 11 :
819 !prefixcmp(name, "refs/tags/") ? 10 :
820 !prefixcmp(name, "refs/remotes/") ? 13 :
821 0);
822}
823
79803322
SP
824const char *ref_rev_parse_rules[] = {
825 "%.*s",
826 "refs/%.*s",
827 "refs/tags/%.*s",
828 "refs/heads/%.*s",
829 "refs/remotes/%.*s",
830 "refs/remotes/%.*s/HEAD",
831 NULL
832};
833
605b4978
SP
834const char *ref_fetch_rules[] = {
835 "%.*s",
836 "refs/%.*s",
837 "refs/heads/%.*s",
838 NULL
839};
840
79803322
SP
841int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
842{
843 const char **p;
844 const int abbrev_name_len = strlen(abbrev_name);
845
846 for (p = rules; *p; p++) {
847 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
848 return 1;
849 }
850 }
851
852 return 0;
853}
854
e5f38ec3 855static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
856 const unsigned char *old_sha1, int mustexist)
857{
8da19775 858 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 859 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
860 unlock_ref(lock);
861 return NULL;
862 }
a89fccd2 863 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 864 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
865 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
866 unlock_ref(lock);
867 return NULL;
868 }
869 return lock;
870}
871
7155b727 872static int remove_empty_directories(const char *file)
bc7127ef
JH
873{
874 /* we want to create a file but there is a directory there;
875 * if that is an empty directory (or a directory that contains
876 * only empty directories), remove them.
877 */
7155b727
JS
878 struct strbuf path;
879 int result;
bc7127ef 880
7155b727
JS
881 strbuf_init(&path, 20);
882 strbuf_addstr(&path, file);
883
a0f4afbe 884 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
885
886 strbuf_release(&path);
887
888 return result;
bc7127ef
JH
889}
890
c976d415
LH
891static int is_refname_available(const char *ref, const char *oldref,
892 struct ref_list *list, int quiet)
893{
894 int namlen = strlen(ref); /* e.g. 'foo/bar' */
895 while (list) {
896 /* list->name could be 'foo' or 'foo/bar/baz' */
897 if (!oldref || strcmp(oldref, list->name)) {
898 int len = strlen(list->name);
899 int cmplen = (namlen < len) ? namlen : len;
900 const char *lead = (namlen < len) ? list->name : ref;
901 if (!strncmp(ref, list->name, cmplen) &&
902 lead[cmplen] == '/') {
903 if (!quiet)
904 error("'%s' exists; cannot create '%s'",
905 list->name, ref);
906 return 0;
907 }
908 }
909 list = list->next;
910 }
911 return 1;
912}
913
68db31cc 914static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
4bd18c43 915{
434cd0cd 916 char *ref_file;
ed378ec7 917 const char *orig_ref = ref;
4bd18c43 918 struct ref_lock *lock;
5cc3cef9 919 int last_errno = 0;
acd3b9ec 920 int type, lflags;
4431fcc4 921 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 922 int missing = 0;
4bd18c43
SP
923
924 lock = xcalloc(1, sizeof(struct ref_lock));
925 lock->lock_fd = -1;
926
68db31cc 927 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
bc7127ef
JH
928 if (!ref && errno == EISDIR) {
929 /* we are trying to lock foo but we used to
930 * have foo/bar which now does not exist;
931 * it is normal for the empty directory 'foo'
932 * to remain.
933 */
934 ref_file = git_path("%s", orig_ref);
5cc3cef9
JH
935 if (remove_empty_directories(ref_file)) {
936 last_errno = errno;
937 error("there are still refs under '%s'", orig_ref);
938 goto error_return;
939 }
68db31cc 940 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
bc7127ef 941 }
68db31cc
SV
942 if (type_p)
943 *type_p = type;
ed378ec7 944 if (!ref) {
5cc3cef9 945 last_errno = errno;
818f477c 946 error("unable to resolve reference %s: %s",
ed378ec7 947 orig_ref, strerror(errno));
5cc3cef9 948 goto error_return;
4bd18c43 949 }
5bdd8d4a 950 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
951 /* When the ref did not exist and we are creating it,
952 * make sure there is no existing ref that is packed
953 * whose name begins with our refname, nor a ref whose
954 * name is a proper prefix of our refname.
955 */
5bdd8d4a 956 if (missing &&
f475e08e
JK
957 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
958 last_errno = ENOTDIR;
c976d415 959 goto error_return;
f475e08e 960 }
22a3844e 961
c33d5174 962 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 963
acd3b9ec
JH
964 lflags = LOCK_DIE_ON_ERROR;
965 if (flags & REF_NODEREF) {
68db31cc 966 ref = orig_ref;
acd3b9ec
JH
967 lflags |= LOCK_NODEREF;
968 }
434cd0cd 969 lock->ref_name = xstrdup(ref);
1655707c 970 lock->orig_ref_name = xstrdup(orig_ref);
7c1a278d 971 ref_file = git_path("%s", ref);
5bdd8d4a 972 if (missing)
68db31cc
SV
973 lock->force_write = 1;
974 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
975 lock->force_write = 1;
4bd18c43 976
5cc3cef9
JH
977 if (safe_create_leading_directories(ref_file)) {
978 last_errno = errno;
979 error("unable to create directory for %s", ref_file);
980 goto error_return;
981 }
4bd18c43 982
acd3b9ec 983 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 984 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
985
986 error_return:
987 unlock_ref(lock);
988 errno = last_errno;
989 return NULL;
4bd18c43
SP
990}
991
4431fcc4 992struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
95fc7512 993{
53cce84c 994 char refpath[PATH_MAX];
95fc7512 995 if (check_ref_format(ref))
4bd18c43 996 return NULL;
53cce84c 997 strcpy(refpath, mkpath("refs/%s", ref));
68db31cc 998 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
999}
1000
68db31cc 1001struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
4bd18c43 1002{
5f7b202a 1003 switch (check_ref_format(ref)) {
5f7b202a 1004 default:
257f3020
JH
1005 return NULL;
1006 case 0:
1007 case CHECK_REF_FORMAT_ONELEVEL:
5f7b202a
JH
1008 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1009 }
c0277d15
JH
1010}
1011
26a063a1
JH
1012static struct lock_file packlock;
1013
c0277d15
JH
1014static int repack_without_ref(const char *refname)
1015{
1016 struct ref_list *list, *packed_ref_list;
1017 int fd;
1018 int found = 0;
c0277d15
JH
1019
1020 packed_ref_list = get_packed_refs();
1021 for (list = packed_ref_list; list; list = list->next) {
1022 if (!strcmp(refname, list->name)) {
1023 found = 1;
1024 break;
1025 }
1026 }
1027 if (!found)
1028 return 0;
c0277d15 1029 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1b018fd9
MV
1030 if (fd < 0) {
1031 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1032 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1033 }
c0277d15
JH
1034
1035 for (list = packed_ref_list; list; list = list->next) {
1036 char line[PATH_MAX + 100];
1037 int len;
1038
1039 if (!strcmp(refname, list->name))
1040 continue;
1041 len = snprintf(line, sizeof(line), "%s %s\n",
1042 sha1_to_hex(list->sha1), list->name);
1043 /* this should not happen but just being defensive */
1044 if (len > sizeof(line))
1045 die("too long a refname '%s'", list->name);
1046 write_or_die(fd, line, len);
1047 }
1048 return commit_lock_file(&packlock);
1049}
1050
eca35a25 1051int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1052{
1053 struct ref_lock *lock;
eca35a25 1054 int err, i = 0, ret = 0, flag = 0;
c0277d15 1055
68db31cc 1056 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1057 if (!lock)
1058 return 1;
045a476f 1059 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1060 /* loose */
eca35a25
MV
1061 const char *path;
1062
1063 if (!(delopt & REF_NODEREF)) {
1064 i = strlen(lock->lk->filename) - 5; /* .lock */
1065 lock->lk->filename[i] = 0;
1066 path = lock->lk->filename;
1067 } else {
9db56f71 1068 path = git_path("%s", refname);
eca35a25 1069 }
691f1a28
AR
1070 err = unlink_or_warn(path);
1071 if (err && errno != ENOENT)
c0277d15 1072 ret = 1;
691f1a28 1073
eca35a25
MV
1074 if (!(delopt & REF_NODEREF))
1075 lock->lk->filename[i] = '.';
c0277d15
JH
1076 }
1077 /* removing the loose one could have resurrected an earlier
1078 * packed one. Also, if it was not loose we need to repack
1079 * without it.
1080 */
1081 ret |= repack_without_ref(refname);
1082
691f1a28 1083 unlink_or_warn(git_path("logs/%s", lock->ref_name));
c0277d15
JH
1084 invalidate_cached_refs();
1085 unlock_ref(lock);
1086 return ret;
4bd18c43
SP
1087}
1088
678d0f4c 1089int rename_ref(const char *oldref, const char *newref, const char *logmsg)
c976d415
LH
1090{
1091 static const char renamed_ref[] = "RENAMED-REF";
1092 unsigned char sha1[20], orig_sha1[20];
1093 int flag = 0, logmoved = 0;
1094 struct ref_lock *lock;
c976d415 1095 struct stat loginfo;
16c2bfbb 1096 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
eca35a25 1097 const char *symref = NULL;
c976d415 1098
450d4c0f 1099 if (log && S_ISLNK(loginfo.st_mode))
c976d415
LH
1100 return error("reflog for %s is a symlink", oldref);
1101
eca35a25
MV
1102 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1103 if (flag & REF_ISSYMREF)
fa58186c
MV
1104 return error("refname %s is a symbolic ref, renaming it is not supported",
1105 oldref);
eca35a25 1106 if (!symref)
c976d415
LH
1107 return error("refname %s not found", oldref);
1108
1109 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1110 return 1;
1111
1112 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1113 return 1;
1114
68db31cc 1115 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
c976d415
LH
1116 if (!lock)
1117 return error("unable to lock %s", renamed_ref);
1118 lock->force_write = 1;
678d0f4c 1119 if (write_ref_sha1(lock, orig_sha1, logmsg))
c976d415
LH
1120 return error("unable to save current sha1 in %s", renamed_ref);
1121
1122 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1123 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1124 oldref, strerror(errno));
1125
eca35a25 1126 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
c976d415
LH
1127 error("unable to delete old %s", oldref);
1128 goto rollback;
1129 }
1130
eca35a25 1131 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
c976d415
LH
1132 if (errno==EISDIR) {
1133 if (remove_empty_directories(git_path("%s", newref))) {
1134 error("Directory not empty: %s", newref);
1135 goto rollback;
1136 }
1137 } else {
1138 error("unable to delete existing %s", newref);
1139 goto rollback;
1140 }
1141 }
1142
1143 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1144 error("unable to create directory for %s", newref);
1145 goto rollback;
1146 }
1147
1148 retry:
1149 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
d9e74d57
JR
1150 if (errno==EISDIR || errno==ENOTDIR) {
1151 /*
1152 * rename(a, b) when b is an existing
1153 * directory ought to result in ISDIR, but
1154 * Solaris 5.8 gives ENOTDIR. Sheesh.
1155 */
c976d415
LH
1156 if (remove_empty_directories(git_path("logs/%s", newref))) {
1157 error("Directory not empty: logs/%s", newref);
1158 goto rollback;
1159 }
1160 goto retry;
1161 } else {
1162 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1163 newref, strerror(errno));
1164 goto rollback;
1165 }
1166 }
1167 logmoved = log;
1168
68db31cc 1169 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
c976d415
LH
1170 if (!lock) {
1171 error("unable to lock %s for update", newref);
1172 goto rollback;
1173 }
c976d415
LH
1174 lock->force_write = 1;
1175 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1176 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
c976d415
LH
1177 error("unable to write current sha1 into %s", newref);
1178 goto rollback;
1179 }
1180
1181 return 0;
1182
1183 rollback:
68db31cc 1184 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
c976d415
LH
1185 if (!lock) {
1186 error("unable to lock %s for rollback", oldref);
1187 goto rollbacklog;
1188 }
1189
1190 lock->force_write = 1;
1191 flag = log_all_ref_updates;
1192 log_all_ref_updates = 0;
1193 if (write_ref_sha1(lock, orig_sha1, NULL))
1194 error("unable to write current sha1 into %s", oldref);
1195 log_all_ref_updates = flag;
1196
1197 rollbacklog:
1198 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1199 error("unable to restore logfile %s from %s: %s",
1200 oldref, newref, strerror(errno));
1201 if (!logmoved && log &&
1202 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1203 error("unable to restore logfile %s from tmp-renamed-log: %s",
1204 oldref, strerror(errno));
1205
1206 return 1;
1207}
1208
435fc852 1209int close_ref(struct ref_lock *lock)
b531394d
BC
1210{
1211 if (close_lock_file(lock->lk))
1212 return -1;
1213 lock->lock_fd = -1;
1214 return 0;
1215}
1216
435fc852 1217int commit_ref(struct ref_lock *lock)
b531394d
BC
1218{
1219 if (commit_lock_file(lock->lk))
1220 return -1;
1221 lock->lock_fd = -1;
1222 return 0;
1223}
1224
e5f38ec3 1225void unlock_ref(struct ref_lock *lock)
4bd18c43 1226{
4ed7cd3a
BC
1227 /* Do not free lock->lk -- atexit() still looks at them */
1228 if (lock->lk)
1229 rollback_lock_file(lock->lk);
434cd0cd 1230 free(lock->ref_name);
1655707c 1231 free(lock->orig_ref_name);
4bd18c43
SP
1232 free(lock);
1233}
1234
0ec29a47
JH
1235/*
1236 * copy the reflog message msg to buf, which has been allocated sufficiently
1237 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1238 * because reflog file is one line per entry.
1239 */
1240static int copy_msg(char *buf, const char *msg)
1241{
1242 char *cp = buf;
1243 char c;
1244 int wasspace = 1;
1245
1246 *cp++ = '\t';
1247 while ((c = *msg++)) {
1248 if (wasspace && isspace(c))
1249 continue;
1250 wasspace = isspace(c);
1251 if (wasspace)
1252 c = ' ';
1253 *cp++ = c;
1254 }
1255 while (buf < cp && isspace(cp[-1]))
1256 cp--;
1257 *cp++ = '\n';
1258 return cp - buf;
1259}
1260
9a13f0b7
NP
1261static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1262 const unsigned char *new_sha1, const char *msg)
6de08ae6
SP
1263{
1264 int logfd, written, oflags = O_APPEND | O_WRONLY;
1265 unsigned maxlen, len;
8ac65937 1266 int msglen;
958a4789
AR
1267 char log_file[PATH_MAX];
1268 char *logrec;
ff4c8485 1269 const char *committer;
6de08ae6 1270
510c5a8e 1271 if (log_all_ref_updates < 0)
7d1864ce 1272 log_all_ref_updates = !is_bare_repository();
510c5a8e 1273
958a4789 1274 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
9a13f0b7 1275
4057deb5 1276 if (log_all_ref_updates &&
cc44c765
JH
1277 (!prefixcmp(ref_name, "refs/heads/") ||
1278 !prefixcmp(ref_name, "refs/remotes/") ||
b2e256b0 1279 !prefixcmp(ref_name, "refs/notes/") ||
bd104db1 1280 !strcmp(ref_name, "HEAD"))) {
9a13f0b7 1281 if (safe_create_leading_directories(log_file) < 0)
6de08ae6 1282 return error("unable to create directory for %s",
9a13f0b7 1283 log_file);
6de08ae6
SP
1284 oflags |= O_CREAT;
1285 }
1286
9a13f0b7 1287 logfd = open(log_file, oflags, 0666);
6de08ae6 1288 if (logfd < 0) {
1974bf62 1289 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1290 return 0;
3b463c3f
JH
1291
1292 if ((oflags & O_CREAT) && errno == EISDIR) {
9a13f0b7 1293 if (remove_empty_directories(log_file)) {
3b463c3f 1294 return error("There are still logs under '%s'",
9a13f0b7 1295 log_file);
3b463c3f 1296 }
9a13f0b7 1297 logfd = open(log_file, oflags, 0666);
3b463c3f
JH
1298 }
1299
1300 if (logfd < 0)
1301 return error("Unable to append to %s: %s",
9a13f0b7 1302 log_file, strerror(errno));
6de08ae6
SP
1303 }
1304
443b92b6
MK
1305 adjust_shared_perm(log_file);
1306
0ec29a47 1307 msglen = msg ? strlen(msg) : 0;
774751a8 1308 committer = git_committer_info(0);
8ac65937
JH
1309 maxlen = strlen(committer) + msglen + 100;
1310 logrec = xmalloc(maxlen);
1311 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1312 sha1_to_hex(old_sha1),
1313 sha1_to_hex(new_sha1),
8ac65937
JH
1314 committer);
1315 if (msglen)
0ec29a47 1316 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1317 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1318 free(logrec);
91c8d590 1319 if (close(logfd) != 0 || written != len)
9a13f0b7 1320 return error("Unable to append to %s", log_file);
6de08ae6
SP
1321 return 0;
1322}
1323
c3b0dec5
LT
1324static int is_branch(const char *refname)
1325{
1326 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1327}
1328
4bd18c43
SP
1329int write_ref_sha1(struct ref_lock *lock,
1330 const unsigned char *sha1, const char *logmsg)
1331{
1332 static char term = '\n';
c3b0dec5 1333 struct object *o;
4bd18c43
SP
1334
1335 if (!lock)
95fc7512 1336 return -1;
a89fccd2 1337 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1338 unlock_ref(lock);
1339 return 0;
95fc7512 1340 }
c3b0dec5
LT
1341 o = parse_object(sha1);
1342 if (!o) {
1343 error("Trying to write ref %s with nonexistant object %s",
1344 lock->ref_name, sha1_to_hex(sha1));
1345 unlock_ref(lock);
1346 return -1;
1347 }
1348 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1349 error("Trying to write non-commit object %s to branch %s",
1350 sha1_to_hex(sha1), lock->ref_name);
1351 unlock_ref(lock);
1352 return -1;
1353 }
93822c22
AW
1354 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1355 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1356 || close_ref(lock) < 0) {
c33d5174 1357 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1358 unlock_ref(lock);
1359 return -1;
1360 }
5e290ff7 1361 invalidate_cached_refs();
bd104db1
NP
1362 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1363 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1364 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1365 unlock_ref(lock);
1366 return -1;
1367 }
605fac8b
NP
1368 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1369 /*
1370 * Special hack: If a branch is updated directly and HEAD
1371 * points to it (may happen on the remote side of a push
1372 * for example) then logically the HEAD reflog should be
1373 * updated too.
1374 * A generic solution implies reverse symref information,
1375 * but finding all symrefs pointing to the given branch
1376 * would be rather costly for this rare event (the direct
1377 * update of a branch) to be worth it. So let's cheat and
1378 * check with HEAD only which should cover 99% of all usage
1379 * scenarios (even 100% of the default ones).
1380 */
1381 unsigned char head_sha1[20];
1382 int head_flag;
1383 const char *head_ref;
1384 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1385 if (head_ref && (head_flag & REF_ISSYMREF) &&
1386 !strcmp(head_ref, lock->ref_name))
1387 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1388 }
b531394d 1389 if (commit_ref(lock)) {
434cd0cd 1390 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1391 unlock_ref(lock);
1392 return -1;
1393 }
4bd18c43
SP
1394 unlock_ref(lock);
1395 return 0;
95fc7512 1396}
d556fae2 1397
8b5157e4
NP
1398int create_symref(const char *ref_target, const char *refs_heads_master,
1399 const char *logmsg)
41b625b0
NP
1400{
1401 const char *lockpath;
1402 char ref[1000];
1403 int fd, len, written;
a4f34cbb 1404 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1405 unsigned char old_sha1[20], new_sha1[20];
1406
1407 if (logmsg && read_ref(ref_target, old_sha1))
1408 hashclr(old_sha1);
41b625b0 1409
d48744d1
JH
1410 if (safe_create_leading_directories(git_HEAD) < 0)
1411 return error("unable to create directory for %s", git_HEAD);
1412
41b625b0
NP
1413#ifndef NO_SYMLINK_HEAD
1414 if (prefer_symlink_refs) {
1415 unlink(git_HEAD);
1416 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1417 goto done;
41b625b0
NP
1418 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1419 }
1420#endif
1421
1422 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1423 if (sizeof(ref) <= len) {
1424 error("refname too long: %s", refs_heads_master);
47fc52e2 1425 goto error_free_return;
41b625b0
NP
1426 }
1427 lockpath = mkpath("%s.lock", git_HEAD);
1428 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1429 if (fd < 0) {
1430 error("Unable to open %s for writing", lockpath);
47fc52e2 1431 goto error_free_return;
41b625b0
NP
1432 }
1433 written = write_in_full(fd, ref, len);
91c8d590 1434 if (close(fd) != 0 || written != len) {
41b625b0 1435 error("Unable to write to %s", lockpath);
47fc52e2 1436 goto error_unlink_return;
41b625b0
NP
1437 }
1438 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1439 error("Unable to create %s", git_HEAD);
47fc52e2 1440 goto error_unlink_return;
41b625b0
NP
1441 }
1442 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1443 error("Unable to fix permissions on %s", lockpath);
47fc52e2 1444 error_unlink_return:
691f1a28 1445 unlink_or_warn(lockpath);
47fc52e2
JH
1446 error_free_return:
1447 free(git_HEAD);
1448 return -1;
41b625b0 1449 }
8b5157e4 1450
ee96d11b 1451#ifndef NO_SYMLINK_HEAD
8b5157e4 1452 done:
ee96d11b 1453#endif
8b5157e4
NP
1454 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1455 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1456
47fc52e2 1457 free(git_HEAD);
41b625b0
NP
1458 return 0;
1459}
1460
16d7cc90
JH
1461static char *ref_msg(const char *line, const char *endp)
1462{
1463 const char *ep;
16d7cc90 1464 line += 82;
182af834
PH
1465 ep = memchr(line, '\n', endp - line);
1466 if (!ep)
1467 ep = endp;
1468 return xmemdupz(line, ep - line);
16d7cc90
JH
1469}
1470
1471int 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 1472{
e5229042 1473 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1474 char *tz_c;
e29cb53a 1475 int logfd, tz, reccnt = 0;
d556fae2
SP
1476 struct stat st;
1477 unsigned long date;
e5229042 1478 unsigned char logged_sha1[20];
cb48cb58 1479 void *log_mapped;
dc49cd76 1480 size_t mapsz;
d556fae2
SP
1481
1482 logfile = git_path("logs/%s", ref);
1483 logfd = open(logfile, O_RDONLY, 0);
1484 if (logfd < 0)
d824cbba 1485 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
1486 fstat(logfd, &st);
1487 if (!st.st_size)
1488 die("Log %s is empty.", logfile);
dc49cd76
SP
1489 mapsz = xsize_t(st.st_size);
1490 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1491 logdata = log_mapped;
d556fae2
SP
1492 close(logfd);
1493
e5229042 1494 lastrec = NULL;
d556fae2
SP
1495 rec = logend = logdata + st.st_size;
1496 while (logdata < rec) {
e29cb53a 1497 reccnt++;
d556fae2
SP
1498 if (logdata < rec && *(rec-1) == '\n')
1499 rec--;
e5229042
SP
1500 lastgt = NULL;
1501 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1502 rec--;
e5229042
SP
1503 if (*rec == '>')
1504 lastgt = rec;
1505 }
1506 if (!lastgt)
d556fae2 1507 die("Log %s is corrupt.", logfile);
e5229042 1508 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1509 if (date <= at_time || cnt == 0) {
76a44c5c 1510 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1511 if (msg)
1512 *msg = ref_msg(rec, logend);
1513 if (cutoff_time)
1514 *cutoff_time = date;
1515 if (cutoff_tz)
1516 *cutoff_tz = tz;
1517 if (cutoff_cnt)
76a44c5c 1518 *cutoff_cnt = reccnt - 1;
e5229042
SP
1519 if (lastrec) {
1520 if (get_sha1_hex(lastrec, logged_sha1))
1521 die("Log %s is corrupt.", logfile);
1522 if (get_sha1_hex(rec + 41, sha1))
1523 die("Log %s is corrupt.", logfile);
a89fccd2 1524 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1525 warning("Log %s has gap after %s.",
73013afd 1526 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1527 }
e5f38ec3
JH
1528 }
1529 else if (date == at_time) {
e5229042
SP
1530 if (get_sha1_hex(rec + 41, sha1))
1531 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1532 }
1533 else {
e5229042
SP
1534 if (get_sha1_hex(rec + 41, logged_sha1))
1535 die("Log %s is corrupt.", logfile);
a89fccd2 1536 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1537 warning("Log %s unexpectedly ended on %s.",
73013afd 1538 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1539 }
1540 }
dc49cd76 1541 munmap(log_mapped, mapsz);
d556fae2
SP
1542 return 0;
1543 }
e5229042 1544 lastrec = rec;
ab2a1a32
JH
1545 if (cnt > 0)
1546 cnt--;
d556fae2
SP
1547 }
1548
e5229042
SP
1549 rec = logdata;
1550 while (rec < logend && *rec != '>' && *rec != '\n')
1551 rec++;
1552 if (rec == logend || *rec == '\n')
d556fae2 1553 die("Log %s is corrupt.", logfile);
e5229042 1554 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1555 tz = strtoul(tz_c, NULL, 10);
1556 if (get_sha1_hex(logdata, sha1))
1557 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1558 if (is_null_sha1(sha1)) {
1559 if (get_sha1_hex(logdata + 41, sha1))
1560 die("Log %s is corrupt.", logfile);
1561 }
16d7cc90
JH
1562 if (msg)
1563 *msg = ref_msg(logdata, logend);
dc49cd76 1564 munmap(log_mapped, mapsz);
16d7cc90
JH
1565
1566 if (cutoff_time)
1567 *cutoff_time = date;
1568 if (cutoff_tz)
1569 *cutoff_tz = tz;
1570 if (cutoff_cnt)
1571 *cutoff_cnt = reccnt;
1572 return 1;
d556fae2 1573}
2ff81662 1574
101d15e0 1575int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
1576{
1577 const char *logfile;
1578 FILE *logfp;
8ca78803 1579 struct strbuf sb = STRBUF_INIT;
2266bf27 1580 int ret = 0;
2ff81662
JH
1581
1582 logfile = git_path("logs/%s", ref);
1583 logfp = fopen(logfile, "r");
1584 if (!logfp)
883d60fa 1585 return -1;
101d15e0
JH
1586
1587 if (ofs) {
1588 struct stat statbuf;
1589 if (fstat(fileno(logfp), &statbuf) ||
1590 statbuf.st_size < ofs ||
1591 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 1592 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 1593 fclose(logfp);
8ca78803 1594 strbuf_release(&sb);
101d15e0 1595 return -1;
9d33f7c2 1596 }
101d15e0
JH
1597 }
1598
8ca78803 1599 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 1600 unsigned char osha1[20], nsha1[20];
883d60fa
JS
1601 char *email_end, *message;
1602 unsigned long timestamp;
8ca78803 1603 int tz;
2ff81662
JH
1604
1605 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
1606 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1607 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1608 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1609 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
1610 email_end[1] != ' ' ||
1611 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1612 !message || message[0] != ' ' ||
1613 (message[1] != '+' && message[1] != '-') ||
1614 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 1615 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 1616 continue; /* corrupt? */
883d60fa
JS
1617 email_end[1] = '\0';
1618 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
1619 if (message[6] != '\t')
1620 message += 6;
1621 else
1622 message += 7;
8ca78803
RS
1623 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1624 cb_data);
883d60fa 1625 if (ret)
2266bf27 1626 break;
2ff81662
JH
1627 }
1628 fclose(logfp);
8ca78803 1629 strbuf_release(&sb);
2266bf27 1630 return ret;
2ff81662 1631}
e29cb53a 1632
101d15e0
JH
1633int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1634{
1635 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1636}
1637
eb8381c8
NP
1638static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1639{
1640 DIR *dir = opendir(git_path("logs/%s", base));
fcee5a14 1641 int retval = 0;
eb8381c8
NP
1642
1643 if (dir) {
1644 struct dirent *de;
1645 int baselen = strlen(base);
1646 char *log = xmalloc(baselen + 257);
1647
1648 memcpy(log, base, baselen);
1649 if (baselen && base[baselen-1] != '/')
1650 log[baselen++] = '/';
1651
1652 while ((de = readdir(dir)) != NULL) {
1653 struct stat st;
1654 int namelen;
1655
1656 if (de->d_name[0] == '.')
1657 continue;
1658 namelen = strlen(de->d_name);
1659 if (namelen > 255)
1660 continue;
1661 if (has_extension(de->d_name, ".lock"))
1662 continue;
1663 memcpy(log + baselen, de->d_name, namelen+1);
1664 if (stat(git_path("logs/%s", log), &st) < 0)
1665 continue;
1666 if (S_ISDIR(st.st_mode)) {
1667 retval = do_for_each_reflog(log, fn, cb_data);
1668 } else {
1669 unsigned char sha1[20];
1670 if (!resolve_ref(log, sha1, 0, NULL))
1671 retval = error("bad ref for %s", log);
1672 else
1673 retval = fn(log, sha1, 0, cb_data);
1674 }
1675 if (retval)
1676 break;
1677 }
1678 free(log);
1679 closedir(dir);
1680 }
acb39f64 1681 else if (*base)
fcee5a14 1682 return errno;
eb8381c8
NP
1683 return retval;
1684}
1685
1686int for_each_reflog(each_ref_fn fn, void *cb_data)
1687{
1688 return do_for_each_reflog("", fn, cb_data);
1689}
3d9f037c
CR
1690
1691int update_ref(const char *action, const char *refname,
1692 const unsigned char *sha1, const unsigned char *oldval,
1693 int flags, enum action_on_err onerr)
1694{
1695 static struct ref_lock *lock;
1696 lock = lock_any_ref_for_update(refname, oldval, flags);
1697 if (!lock) {
1698 const char *str = "Cannot lock the ref '%s'.";
1699 switch (onerr) {
1700 case MSG_ON_ERR: error(str, refname); break;
1701 case DIE_ON_ERR: die(str, refname); break;
1702 case QUIET_ON_ERR: break;
1703 }
1704 return 1;
1705 }
1706 if (write_ref_sha1(lock, sha1, action) < 0) {
1707 const char *str = "Cannot update the ref '%s'.";
1708 switch (onerr) {
1709 case MSG_ON_ERR: error(str, refname); break;
1710 case DIE_ON_ERR: die(str, refname); break;
1711 case QUIET_ON_ERR: break;
1712 }
1713 return 1;
1714 }
1715 return 0;
1716}
cda69f48 1717
5483f799 1718struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
1719{
1720 for ( ; list; list = list->next)
1721 if (!strcmp(list->name, name))
5483f799 1722 return (struct ref *)list;
cda69f48
JK
1723 return NULL;
1724}
7c2b3029
JK
1725
1726/*
1727 * generate a format suitable for scanf from a ref_rev_parse_rules
1728 * rule, that is replace the "%.*s" spec with a "%s" spec
1729 */
1730static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1731{
1732 char *spec;
1733
1734 spec = strstr(rule, "%.*s");
1735 if (!spec || strstr(spec + 4, "%.*s"))
1736 die("invalid rule in ref_rev_parse_rules: %s", rule);
1737
1738 /* copy all until spec */
1739 strncpy(scanf_fmt, rule, spec - rule);
1740 scanf_fmt[spec - rule] = '\0';
1741 /* copy new spec */
1742 strcat(scanf_fmt, "%s");
1743 /* copy remaining rule */
1744 strcat(scanf_fmt, spec + 4);
1745
1746 return;
1747}
1748
6e7b3309 1749char *shorten_unambiguous_ref(const char *ref, int strict)
7c2b3029
JK
1750{
1751 int i;
1752 static char **scanf_fmts;
1753 static int nr_rules;
1754 char *short_name;
1755
1756 /* pre generate scanf formats from ref_rev_parse_rules[] */
1757 if (!nr_rules) {
1758 size_t total_len = 0;
1759
1760 /* the rule list is NULL terminated, count them first */
1761 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1762 /* no +1 because strlen("%s") < strlen("%.*s") */
1763 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1764
1765 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1766
1767 total_len = 0;
1768 for (i = 0; i < nr_rules; i++) {
1769 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1770 + total_len;
1771 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1772 total_len += strlen(ref_rev_parse_rules[i]);
1773 }
1774 }
1775
1776 /* bail out if there are no rules */
1777 if (!nr_rules)
1778 return xstrdup(ref);
1779
1780 /* buffer for scanf result, at most ref must fit */
1781 short_name = xstrdup(ref);
1782
1783 /* skip first rule, it will always match */
1784 for (i = nr_rules - 1; i > 0 ; --i) {
1785 int j;
6e7b3309 1786 int rules_to_fail = i;
7c2b3029
JK
1787 int short_name_len;
1788
1789 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1790 continue;
1791
1792 short_name_len = strlen(short_name);
1793
6e7b3309
BW
1794 /*
1795 * in strict mode, all (except the matched one) rules
1796 * must fail to resolve to a valid non-ambiguous ref
1797 */
1798 if (strict)
1799 rules_to_fail = nr_rules;
1800
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1801 /*
1802 * check if the short name resolves to a valid ref,
1803 * but use only rules prior to the matched one
1804 */
6e7b3309 1805 for (j = 0; j < rules_to_fail; j++) {
7c2b3029
JK
1806 const char *rule = ref_rev_parse_rules[j];
1807 unsigned char short_objectname[20];
1808 char refname[PATH_MAX];
1809
6e7b3309
BW
1810 /* skip matched rule */
1811 if (i == j)
1812 continue;
1813
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JK
1814 /*
1815 * the short name is ambiguous, if it resolves
1816 * (with this previous rule) to a valid ref
1817 * read_ref() returns 0 on success
1818 */
1819 mksnpath(refname, sizeof(refname),
1820 rule, short_name_len, short_name);
1821 if (!read_ref(refname, short_objectname))
1822 break;
1823 }
1824
1825 /*
1826 * short name is non-ambiguous if all previous rules
1827 * haven't resolved to a valid ref
1828 */
6e7b3309 1829 if (j == rules_to_fail)
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JK
1830 return short_name;
1831 }
1832
1833 free(short_name);
1834 return xstrdup(ref);
1835}