interpret_nth_last_branch(): plug small memleak
[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 }
8da19775 278 if (!resolve_ref(ref, sha1, 1, &flag)) {
ed378ec7 279 error("%s points nowhere!", ref);
e1e22e37
LT
280 continue;
281 }
f4204ab9 282 list = add_ref(ref, sha1, flag, list, NULL);
e1e22e37 283 }
ed378ec7 284 free(ref);
e1e22e37
LT
285 closedir(dir);
286 }
c774aab9 287 return sort_ref_list(list);
e1e22e37
LT
288}
289
290static struct ref_list *get_loose_refs(void)
291{
5e290ff7
JH
292 if (!cached_refs.did_loose) {
293 cached_refs.loose = get_ref_dir("refs", NULL);
294 cached_refs.did_loose = 1;
e1e22e37 295 }
5e290ff7 296 return cached_refs.loose;
e1e22e37
LT
297}
298
ca8db142
LT
299/* We allow "recursive" symbolic refs. Only within reason, though */
300#define MAXDEPTH 5
0ebde32c
LT
301#define MAXREFLEN (1024)
302
303static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
304{
305 FILE *f;
306 struct cached_refs refs;
307 struct ref_list *ref;
308 int retval;
309
310 strcpy(name + pathlen, "packed-refs");
311 f = fopen(name, "r");
312 if (!f)
313 return -1;
314 read_packed_refs(f, &refs);
315 fclose(f);
316 ref = refs.packed;
317 retval = -1;
318 while (ref) {
319 if (!strcmp(ref->name, refname)) {
320 retval = 0;
321 memcpy(result, ref->sha1, 20);
322 break;
323 }
324 ref = ref->next;
325 }
326 free_ref_list(refs.packed);
327 return retval;
328}
329
330static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
331{
332 int fd, len = strlen(refname);
333 char buffer[128], *p;
334
335 if (recursion > MAXDEPTH || len > MAXREFLEN)
336 return -1;
337 memcpy(name + pathlen, refname, len+1);
338 fd = open(name, O_RDONLY);
339 if (fd < 0)
340 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
341
342 len = read(fd, buffer, sizeof(buffer)-1);
343 close(fd);
344 if (len < 0)
345 return -1;
346 while (len && isspace(buffer[len-1]))
347 len--;
348 buffer[len] = 0;
349
350 /* Was it a detached head or an old-fashioned symlink? */
351 if (!get_sha1_hex(buffer, result))
352 return 0;
353
354 /* Symref? */
355 if (strncmp(buffer, "ref:", 4))
356 return -1;
357 p = buffer + 4;
358 while (isspace(*p))
359 p++;
360
361 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
362}
363
364int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
365{
366 int len = strlen(path), retval;
367 char *gitdir;
842abf06 368 const char *tmp;
0ebde32c
LT
369
370 while (len && path[len-1] == '/')
371 len--;
372 if (!len)
373 return -1;
374 gitdir = xmalloc(len + MAXREFLEN + 8);
375 memcpy(gitdir, path, len);
842abf06
LH
376 memcpy(gitdir + len, "/.git", 6);
377 len += 5;
378
379 tmp = read_gitfile_gently(gitdir);
380 if (tmp) {
381 free(gitdir);
382 len = strlen(tmp);
383 gitdir = xmalloc(len + MAXREFLEN + 3);
384 memcpy(gitdir, tmp, len);
385 }
386 gitdir[len] = '/';
387 gitdir[++len] = '\0';
388 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
0ebde32c
LT
389 free(gitdir);
390 return retval;
391}
ca8db142 392
4886b89f
CC
393/*
394 * If the "reading" argument is set, this function finds out what _object_
395 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
396 * has to exist, and if it is symbolic, it has to point at an existing ref,
397 * because the "read" goes through the symref to the ref it points at.
398 *
399 * The access that is not "reading" may often be "writing", but does not
400 * have to; it can be merely checking _where it leads to_. If it is a
401 * prelude to "writing" to the ref, a write to a symref that points at
402 * yet-to-be-born ref will create the real ref pointed by the symref.
403 * reading=0 allows the caller to check where such a symref leads to.
404 */
8da19775 405const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
8a65ff76 406{
0104ca09
HO
407 int depth = MAXDEPTH;
408 ssize_t len;
a876ed83 409 char buffer[256];
ed378ec7 410 static char ref_buffer[256];
ca8db142 411
8da19775
JH
412 if (flag)
413 *flag = 0;
414
a876ed83 415 for (;;) {
958a4789 416 char path[PATH_MAX];
a876ed83
JH
417 struct stat st;
418 char *buf;
419 int fd;
8a65ff76 420
a876ed83
JH
421 if (--depth < 0)
422 return NULL;
ca8db142 423
958a4789 424 git_snpath(path, sizeof(path), "%s", ref);
4886b89f 425 /* Special case: non-existing file. */
a876ed83 426 if (lstat(path, &st) < 0) {
434cd0cd
LT
427 struct ref_list *list = get_packed_refs();
428 while (list) {
f4204ab9 429 if (!strcmp(ref, list->name)) {
434cd0cd 430 hashcpy(sha1, list->sha1);
8da19775
JH
431 if (flag)
432 *flag |= REF_ISPACKED;
434cd0cd
LT
433 return ref;
434 }
435 list = list->next;
436 }
a876ed83
JH
437 if (reading || errno != ENOENT)
438 return NULL;
e702496e 439 hashclr(sha1);
ed378ec7 440 return ref;
a876ed83 441 }
ca8db142 442
a876ed83
JH
443 /* Follow "normalized" - ie "refs/.." symlinks by hand */
444 if (S_ISLNK(st.st_mode)) {
445 len = readlink(path, buffer, sizeof(buffer)-1);
446 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
ed378ec7
LT
447 buffer[len] = 0;
448 strcpy(ref_buffer, buffer);
449 ref = ref_buffer;
8da19775
JH
450 if (flag)
451 *flag |= REF_ISSYMREF;
a876ed83
JH
452 continue;
453 }
ca8db142 454 }
a876ed83 455
7a21632f
DS
456 /* Is it a directory? */
457 if (S_ISDIR(st.st_mode)) {
458 errno = EISDIR;
459 return NULL;
460 }
461
a876ed83
JH
462 /*
463 * Anything else, just open it and try to use it as
464 * a ref
465 */
466 fd = open(path, O_RDONLY);
467 if (fd < 0)
468 return NULL;
93d26e4c 469 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83
JH
470 close(fd);
471
472 /*
473 * Is it a symbolic ref?
474 */
475 if (len < 4 || memcmp("ref:", buffer, 4))
476 break;
477 buf = buffer + 4;
478 len -= 4;
479 while (len && isspace(*buf))
480 buf++, len--;
481 while (len && isspace(buf[len-1]))
ed378ec7
LT
482 len--;
483 buf[len] = 0;
484 memcpy(ref_buffer, buf, len + 1);
485 ref = ref_buffer;
8da19775
JH
486 if (flag)
487 *flag |= REF_ISSYMREF;
8a65ff76 488 }
a876ed83
JH
489 if (len < 40 || get_sha1_hex(buffer, sha1))
490 return NULL;
ed378ec7 491 return ref;
a876ed83
JH
492}
493
ed378ec7 494int read_ref(const char *ref, unsigned char *sha1)
a876ed83 495{
8da19775 496 if (resolve_ref(ref, sha1, 1, NULL))
a876ed83
JH
497 return 0;
498 return -1;
8a65ff76
LT
499}
500
ef06b918
JH
501static int do_one_ref(const char *base, each_ref_fn fn, int trim,
502 void *cb_data, struct ref_list *entry)
503{
504 if (strncmp(base, entry->name, trim))
505 return 0;
506 if (is_null_sha1(entry->sha1))
507 return 0;
508 if (!has_sha1_file(entry->sha1)) {
509 error("%s does not point to a valid object!", entry->name);
510 return 0;
511 }
0ae91be0 512 current_ref = entry;
ef06b918
JH
513 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
514}
515
cf0adba7
JH
516int peel_ref(const char *ref, unsigned char *sha1)
517{
518 int flag;
519 unsigned char base[20];
520 struct object *o;
521
0ae91be0
SP
522 if (current_ref && (current_ref->name == ref
523 || !strcmp(current_ref->name, ref))) {
524 if (current_ref->flag & REF_KNOWS_PEELED) {
525 hashcpy(sha1, current_ref->peeled);
526 return 0;
527 }
528 hashcpy(base, current_ref->sha1);
529 goto fallback;
530 }
531
cf0adba7
JH
532 if (!resolve_ref(ref, base, 1, &flag))
533 return -1;
534
535 if ((flag & REF_ISPACKED)) {
536 struct ref_list *list = get_packed_refs();
cf0adba7
JH
537
538 while (list) {
f4204ab9
JH
539 if (!strcmp(list->name, ref)) {
540 if (list->flag & REF_KNOWS_PEELED) {
541 hashcpy(sha1, list->peeled);
542 return 0;
543 }
544 /* older pack-refs did not leave peeled ones */
545 break;
cf0adba7
JH
546 }
547 list = list->next;
548 }
cf0adba7
JH
549 }
550
0ae91be0 551fallback:
cf0adba7 552 o = parse_object(base);
8c87dc77 553 if (o && o->type == OBJ_TAG) {
cf0adba7
JH
554 o = deref_tag(o, ref, 0);
555 if (o) {
556 hashcpy(sha1, o->sha1);
557 return 0;
558 }
559 }
560 return -1;
561}
562
8da19775
JH
563static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
564 void *cb_data)
8a65ff76 565{
0ae91be0 566 int retval = 0;
e1e22e37
LT
567 struct ref_list *packed = get_packed_refs();
568 struct ref_list *loose = get_loose_refs();
8a65ff76 569
e142a3c6
DB
570 struct ref_list *extra;
571
572 for (extra = extra_refs; extra; extra = extra->next)
573 retval = do_one_ref(base, fn, trim, cb_data, extra);
574
e1e22e37
LT
575 while (packed && loose) {
576 struct ref_list *entry;
577 int cmp = strcmp(packed->name, loose->name);
578 if (!cmp) {
579 packed = packed->next;
580 continue;
6cada6a9 581 }
e1e22e37
LT
582 if (cmp > 0) {
583 entry = loose;
584 loose = loose->next;
585 } else {
586 entry = packed;
587 packed = packed->next;
588 }
ef06b918 589 retval = do_one_ref(base, fn, trim, cb_data, entry);
e1e22e37 590 if (retval)
0ae91be0 591 goto end_each;
e1e22e37 592 }
8a65ff76 593
ef06b918
JH
594 for (packed = packed ? packed : loose; packed; packed = packed->next) {
595 retval = do_one_ref(base, fn, trim, cb_data, packed);
596 if (retval)
0ae91be0 597 goto end_each;
8a65ff76 598 }
0ae91be0
SP
599
600end_each:
601 current_ref = NULL;
602 return retval;
8a65ff76
LT
603}
604
cb5d709f 605int head_ref(each_ref_fn fn, void *cb_data)
723c31fe
LT
606{
607 unsigned char sha1[20];
8da19775
JH
608 int flag;
609
610 if (resolve_ref("HEAD", sha1, 1, &flag))
611 return fn("HEAD", sha1, flag, cb_data);
2f34ba32 612 return 0;
723c31fe
LT
613}
614
cb5d709f 615int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 616{
cb5d709f 617 return do_for_each_ref("refs/", fn, 0, cb_data);
a62be77f
SE
618}
619
cb5d709f 620int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 621{
cb5d709f 622 return do_for_each_ref("refs/tags/", fn, 10, cb_data);
a62be77f
SE
623}
624
cb5d709f 625int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 626{
cb5d709f 627 return do_for_each_ref("refs/heads/", fn, 11, cb_data);
a62be77f
SE
628}
629
cb5d709f 630int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 631{
cb5d709f 632 return do_for_each_ref("refs/remotes/", fn, 13, cb_data);
8a65ff76
LT
633}
634
03feddd6
JH
635/*
636 * Make sure "ref" is something reasonable to have under ".git/refs/";
637 * We do not like it if:
638 *
639 * - any path component of it begins with ".", or
640 * - it has double dots "..", or
641 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
642 * - it ends with a "/".
643 */
644
645static inline int bad_ref_char(int ch)
646{
8558fd9e
DB
647 if (((unsigned) ch) <= ' ' ||
648 ch == '~' || ch == '^' || ch == ':')
649 return 1;
650 /* 2.13 Pattern Matching Notation */
651 if (ch == '?' || ch == '[') /* Unsupported */
652 return 1;
653 if (ch == '*') /* Supported at the end */
654 return 2;
655 return 0;
03feddd6
JH
656}
657
95fc7512
DB
658int check_ref_format(const char *ref)
659{
8558fd9e 660 int ch, level, bad_type;
03feddd6
JH
661 const char *cp = ref;
662
663 level = 0;
664 while (1) {
665 while ((ch = *cp++) == '/')
666 ; /* tolerate duplicated slashes */
667 if (!ch)
5f7b202a
JH
668 /* should not end with slashes */
669 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
670
671 /* we are at the beginning of the path component */
8558fd9e 672 if (ch == '.')
5f7b202a 673 return CHECK_REF_FORMAT_ERROR;
8558fd9e
DB
674 bad_type = bad_ref_char(ch);
675 if (bad_type) {
5f7b202a
JH
676 return (bad_type == 2 && !*cp)
677 ? CHECK_REF_FORMAT_WILDCARD
678 : CHECK_REF_FORMAT_ERROR;
8558fd9e 679 }
03feddd6
JH
680
681 /* scan the rest of the path component */
682 while ((ch = *cp++) != 0) {
8558fd9e
DB
683 bad_type = bad_ref_char(ch);
684 if (bad_type) {
5f7b202a
JH
685 return (bad_type == 2 && !*cp)
686 ? CHECK_REF_FORMAT_WILDCARD
687 : CHECK_REF_FORMAT_ERROR;
8558fd9e 688 }
03feddd6
JH
689 if (ch == '/')
690 break;
691 if (ch == '.' && *cp == '.')
5f7b202a 692 return CHECK_REF_FORMAT_ERROR;
03feddd6
JH
693 }
694 level++;
695 if (!ch) {
696 if (level < 2)
5f7b202a
JH
697 return CHECK_REF_FORMAT_ONELEVEL;
698 return CHECK_REF_FORMAT_OK;
03feddd6
JH
699 }
700 }
95fc7512
DB
701}
702
79803322
SP
703const char *ref_rev_parse_rules[] = {
704 "%.*s",
705 "refs/%.*s",
706 "refs/tags/%.*s",
707 "refs/heads/%.*s",
708 "refs/remotes/%.*s",
709 "refs/remotes/%.*s/HEAD",
710 NULL
711};
712
605b4978
SP
713const char *ref_fetch_rules[] = {
714 "%.*s",
715 "refs/%.*s",
716 "refs/heads/%.*s",
717 NULL
718};
719
79803322
SP
720int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
721{
722 const char **p;
723 const int abbrev_name_len = strlen(abbrev_name);
724
725 for (p = rules; *p; p++) {
726 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
727 return 1;
728 }
729 }
730
731 return 0;
732}
733
e5f38ec3 734static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
735 const unsigned char *old_sha1, int mustexist)
736{
8da19775 737 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 738 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
739 unlock_ref(lock);
740 return NULL;
741 }
a89fccd2 742 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 743 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
744 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
745 unlock_ref(lock);
746 return NULL;
747 }
748 return lock;
749}
750
7155b727 751static int remove_empty_directories(const char *file)
bc7127ef
JH
752{
753 /* we want to create a file but there is a directory there;
754 * if that is an empty directory (or a directory that contains
755 * only empty directories), remove them.
756 */
7155b727
JS
757 struct strbuf path;
758 int result;
bc7127ef 759
7155b727
JS
760 strbuf_init(&path, 20);
761 strbuf_addstr(&path, file);
762
763 result = remove_dir_recursively(&path, 1);
764
765 strbuf_release(&path);
766
767 return result;
bc7127ef
JH
768}
769
c976d415
LH
770static int is_refname_available(const char *ref, const char *oldref,
771 struct ref_list *list, int quiet)
772{
773 int namlen = strlen(ref); /* e.g. 'foo/bar' */
774 while (list) {
775 /* list->name could be 'foo' or 'foo/bar/baz' */
776 if (!oldref || strcmp(oldref, list->name)) {
777 int len = strlen(list->name);
778 int cmplen = (namlen < len) ? namlen : len;
779 const char *lead = (namlen < len) ? list->name : ref;
780 if (!strncmp(ref, list->name, cmplen) &&
781 lead[cmplen] == '/') {
782 if (!quiet)
783 error("'%s' exists; cannot create '%s'",
784 list->name, ref);
785 return 0;
786 }
787 }
788 list = list->next;
789 }
790 return 1;
791}
792
68db31cc 793static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
4bd18c43 794{
434cd0cd 795 char *ref_file;
ed378ec7 796 const char *orig_ref = ref;
4bd18c43 797 struct ref_lock *lock;
5cc3cef9 798 int last_errno = 0;
acd3b9ec 799 int type, lflags;
4431fcc4 800 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 801 int missing = 0;
4bd18c43
SP
802
803 lock = xcalloc(1, sizeof(struct ref_lock));
804 lock->lock_fd = -1;
805
68db31cc 806 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
bc7127ef
JH
807 if (!ref && errno == EISDIR) {
808 /* we are trying to lock foo but we used to
809 * have foo/bar which now does not exist;
810 * it is normal for the empty directory 'foo'
811 * to remain.
812 */
813 ref_file = git_path("%s", orig_ref);
5cc3cef9
JH
814 if (remove_empty_directories(ref_file)) {
815 last_errno = errno;
816 error("there are still refs under '%s'", orig_ref);
817 goto error_return;
818 }
68db31cc 819 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
bc7127ef 820 }
68db31cc
SV
821 if (type_p)
822 *type_p = type;
ed378ec7 823 if (!ref) {
5cc3cef9 824 last_errno = errno;
818f477c 825 error("unable to resolve reference %s: %s",
ed378ec7 826 orig_ref, strerror(errno));
5cc3cef9 827 goto error_return;
4bd18c43 828 }
5bdd8d4a 829 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
830 /* When the ref did not exist and we are creating it,
831 * make sure there is no existing ref that is packed
832 * whose name begins with our refname, nor a ref whose
833 * name is a proper prefix of our refname.
834 */
5bdd8d4a 835 if (missing &&
c976d415
LH
836 !is_refname_available(ref, NULL, get_packed_refs(), 0))
837 goto error_return;
22a3844e 838
c33d5174 839 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 840
acd3b9ec
JH
841 lflags = LOCK_DIE_ON_ERROR;
842 if (flags & REF_NODEREF) {
68db31cc 843 ref = orig_ref;
acd3b9ec
JH
844 lflags |= LOCK_NODEREF;
845 }
434cd0cd 846 lock->ref_name = xstrdup(ref);
1655707c 847 lock->orig_ref_name = xstrdup(orig_ref);
7c1a278d 848 ref_file = git_path("%s", ref);
5bdd8d4a 849 if (missing)
68db31cc
SV
850 lock->force_write = 1;
851 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
852 lock->force_write = 1;
4bd18c43 853
5cc3cef9
JH
854 if (safe_create_leading_directories(ref_file)) {
855 last_errno = errno;
856 error("unable to create directory for %s", ref_file);
857 goto error_return;
858 }
4bd18c43 859
acd3b9ec 860 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 861 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
862
863 error_return:
864 unlock_ref(lock);
865 errno = last_errno;
866 return NULL;
4bd18c43
SP
867}
868
4431fcc4 869struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
95fc7512 870{
53cce84c 871 char refpath[PATH_MAX];
95fc7512 872 if (check_ref_format(ref))
4bd18c43 873 return NULL;
53cce84c 874 strcpy(refpath, mkpath("refs/%s", ref));
68db31cc 875 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
876}
877
68db31cc 878struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
4bd18c43 879{
5f7b202a 880 switch (check_ref_format(ref)) {
5f7b202a 881 default:
257f3020
JH
882 return NULL;
883 case 0:
884 case CHECK_REF_FORMAT_ONELEVEL:
5f7b202a
JH
885 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
886 }
c0277d15
JH
887}
888
26a063a1
JH
889static struct lock_file packlock;
890
c0277d15
JH
891static int repack_without_ref(const char *refname)
892{
893 struct ref_list *list, *packed_ref_list;
894 int fd;
895 int found = 0;
c0277d15
JH
896
897 packed_ref_list = get_packed_refs();
898 for (list = packed_ref_list; list; list = list->next) {
899 if (!strcmp(refname, list->name)) {
900 found = 1;
901 break;
902 }
903 }
904 if (!found)
905 return 0;
c0277d15
JH
906 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
907 if (fd < 0)
908 return error("cannot delete '%s' from packed refs", refname);
909
910 for (list = packed_ref_list; list; list = list->next) {
911 char line[PATH_MAX + 100];
912 int len;
913
914 if (!strcmp(refname, list->name))
915 continue;
916 len = snprintf(line, sizeof(line), "%s %s\n",
917 sha1_to_hex(list->sha1), list->name);
918 /* this should not happen but just being defensive */
919 if (len > sizeof(line))
920 die("too long a refname '%s'", list->name);
921 write_or_die(fd, line, len);
922 }
923 return commit_lock_file(&packlock);
924}
925
eca35a25 926int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
927{
928 struct ref_lock *lock;
eca35a25 929 int err, i = 0, ret = 0, flag = 0;
c0277d15 930
68db31cc 931 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
932 if (!lock)
933 return 1;
045a476f 934 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 935 /* loose */
eca35a25
MV
936 const char *path;
937
938 if (!(delopt & REF_NODEREF)) {
939 i = strlen(lock->lk->filename) - 5; /* .lock */
940 lock->lk->filename[i] = 0;
941 path = lock->lk->filename;
942 } else {
9db56f71 943 path = git_path("%s", refname);
eca35a25
MV
944 }
945 err = unlink(path);
0b294c0a 946 if (err && errno != ENOENT) {
c0277d15
JH
947 ret = 1;
948 error("unlink(%s) failed: %s",
eca35a25 949 path, strerror(errno));
c0277d15 950 }
eca35a25
MV
951 if (!(delopt & REF_NODEREF))
952 lock->lk->filename[i] = '.';
c0277d15
JH
953 }
954 /* removing the loose one could have resurrected an earlier
955 * packed one. Also, if it was not loose we need to repack
956 * without it.
957 */
958 ret |= repack_without_ref(refname);
959
9a13f0b7 960 err = unlink(git_path("logs/%s", lock->ref_name));
c0277d15
JH
961 if (err && errno != ENOENT)
962 fprintf(stderr, "warning: unlink(%s) failed: %s",
9a13f0b7 963 git_path("logs/%s", lock->ref_name), strerror(errno));
c0277d15
JH
964 invalidate_cached_refs();
965 unlock_ref(lock);
966 return ret;
4bd18c43
SP
967}
968
678d0f4c 969int rename_ref(const char *oldref, const char *newref, const char *logmsg)
c976d415
LH
970{
971 static const char renamed_ref[] = "RENAMED-REF";
972 unsigned char sha1[20], orig_sha1[20];
973 int flag = 0, logmoved = 0;
974 struct ref_lock *lock;
c976d415 975 struct stat loginfo;
16c2bfbb 976 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
eca35a25 977 const char *symref = NULL;
c976d415 978
450d4c0f 979 if (log && S_ISLNK(loginfo.st_mode))
c976d415
LH
980 return error("reflog for %s is a symlink", oldref);
981
eca35a25
MV
982 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
983 if (flag & REF_ISSYMREF)
fa58186c
MV
984 return error("refname %s is a symbolic ref, renaming it is not supported",
985 oldref);
eca35a25 986 if (!symref)
c976d415
LH
987 return error("refname %s not found", oldref);
988
989 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
990 return 1;
991
992 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
993 return 1;
994
68db31cc 995 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
c976d415
LH
996 if (!lock)
997 return error("unable to lock %s", renamed_ref);
998 lock->force_write = 1;
678d0f4c 999 if (write_ref_sha1(lock, orig_sha1, logmsg))
c976d415
LH
1000 return error("unable to save current sha1 in %s", renamed_ref);
1001
1002 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1003 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1004 oldref, strerror(errno));
1005
eca35a25 1006 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
c976d415
LH
1007 error("unable to delete old %s", oldref);
1008 goto rollback;
1009 }
1010
eca35a25 1011 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
c976d415
LH
1012 if (errno==EISDIR) {
1013 if (remove_empty_directories(git_path("%s", newref))) {
1014 error("Directory not empty: %s", newref);
1015 goto rollback;
1016 }
1017 } else {
1018 error("unable to delete existing %s", newref);
1019 goto rollback;
1020 }
1021 }
1022
1023 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1024 error("unable to create directory for %s", newref);
1025 goto rollback;
1026 }
1027
1028 retry:
1029 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
d9e74d57
JR
1030 if (errno==EISDIR || errno==ENOTDIR) {
1031 /*
1032 * rename(a, b) when b is an existing
1033 * directory ought to result in ISDIR, but
1034 * Solaris 5.8 gives ENOTDIR. Sheesh.
1035 */
c976d415
LH
1036 if (remove_empty_directories(git_path("logs/%s", newref))) {
1037 error("Directory not empty: logs/%s", newref);
1038 goto rollback;
1039 }
1040 goto retry;
1041 } else {
1042 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1043 newref, strerror(errno));
1044 goto rollback;
1045 }
1046 }
1047 logmoved = log;
1048
68db31cc 1049 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
c976d415
LH
1050 if (!lock) {
1051 error("unable to lock %s for update", newref);
1052 goto rollback;
1053 }
c976d415
LH
1054 lock->force_write = 1;
1055 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1056 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
c976d415
LH
1057 error("unable to write current sha1 into %s", newref);
1058 goto rollback;
1059 }
1060
1061 return 0;
1062
1063 rollback:
68db31cc 1064 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
c976d415
LH
1065 if (!lock) {
1066 error("unable to lock %s for rollback", oldref);
1067 goto rollbacklog;
1068 }
1069
1070 lock->force_write = 1;
1071 flag = log_all_ref_updates;
1072 log_all_ref_updates = 0;
1073 if (write_ref_sha1(lock, orig_sha1, NULL))
1074 error("unable to write current sha1 into %s", oldref);
1075 log_all_ref_updates = flag;
1076
1077 rollbacklog:
1078 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1079 error("unable to restore logfile %s from %s: %s",
1080 oldref, newref, strerror(errno));
1081 if (!logmoved && log &&
1082 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1083 error("unable to restore logfile %s from tmp-renamed-log: %s",
1084 oldref, strerror(errno));
1085
1086 return 1;
1087}
1088
435fc852 1089int close_ref(struct ref_lock *lock)
b531394d
BC
1090{
1091 if (close_lock_file(lock->lk))
1092 return -1;
1093 lock->lock_fd = -1;
1094 return 0;
1095}
1096
435fc852 1097int commit_ref(struct ref_lock *lock)
b531394d
BC
1098{
1099 if (commit_lock_file(lock->lk))
1100 return -1;
1101 lock->lock_fd = -1;
1102 return 0;
1103}
1104
e5f38ec3 1105void unlock_ref(struct ref_lock *lock)
4bd18c43 1106{
4ed7cd3a
BC
1107 /* Do not free lock->lk -- atexit() still looks at them */
1108 if (lock->lk)
1109 rollback_lock_file(lock->lk);
434cd0cd 1110 free(lock->ref_name);
1655707c 1111 free(lock->orig_ref_name);
4bd18c43
SP
1112 free(lock);
1113}
1114
0ec29a47
JH
1115/*
1116 * copy the reflog message msg to buf, which has been allocated sufficiently
1117 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1118 * because reflog file is one line per entry.
1119 */
1120static int copy_msg(char *buf, const char *msg)
1121{
1122 char *cp = buf;
1123 char c;
1124 int wasspace = 1;
1125
1126 *cp++ = '\t';
1127 while ((c = *msg++)) {
1128 if (wasspace && isspace(c))
1129 continue;
1130 wasspace = isspace(c);
1131 if (wasspace)
1132 c = ' ';
1133 *cp++ = c;
1134 }
1135 while (buf < cp && isspace(cp[-1]))
1136 cp--;
1137 *cp++ = '\n';
1138 return cp - buf;
1139}
1140
9a13f0b7
NP
1141static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1142 const unsigned char *new_sha1, const char *msg)
6de08ae6
SP
1143{
1144 int logfd, written, oflags = O_APPEND | O_WRONLY;
1145 unsigned maxlen, len;
8ac65937 1146 int msglen;
958a4789
AR
1147 char log_file[PATH_MAX];
1148 char *logrec;
ff4c8485 1149 const char *committer;
6de08ae6 1150
510c5a8e 1151 if (log_all_ref_updates < 0)
7d1864ce 1152 log_all_ref_updates = !is_bare_repository();
510c5a8e 1153
958a4789 1154 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
9a13f0b7 1155
4057deb5 1156 if (log_all_ref_updates &&
cc44c765
JH
1157 (!prefixcmp(ref_name, "refs/heads/") ||
1158 !prefixcmp(ref_name, "refs/remotes/") ||
bd104db1 1159 !strcmp(ref_name, "HEAD"))) {
9a13f0b7 1160 if (safe_create_leading_directories(log_file) < 0)
6de08ae6 1161 return error("unable to create directory for %s",
9a13f0b7 1162 log_file);
6de08ae6
SP
1163 oflags |= O_CREAT;
1164 }
1165
9a13f0b7 1166 logfd = open(log_file, oflags, 0666);
6de08ae6 1167 if (logfd < 0) {
1974bf62 1168 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1169 return 0;
3b463c3f
JH
1170
1171 if ((oflags & O_CREAT) && errno == EISDIR) {
9a13f0b7 1172 if (remove_empty_directories(log_file)) {
3b463c3f 1173 return error("There are still logs under '%s'",
9a13f0b7 1174 log_file);
3b463c3f 1175 }
9a13f0b7 1176 logfd = open(log_file, oflags, 0666);
3b463c3f
JH
1177 }
1178
1179 if (logfd < 0)
1180 return error("Unable to append to %s: %s",
9a13f0b7 1181 log_file, strerror(errno));
6de08ae6
SP
1182 }
1183
443b92b6
MK
1184 adjust_shared_perm(log_file);
1185
0ec29a47 1186 msglen = msg ? strlen(msg) : 0;
774751a8 1187 committer = git_committer_info(0);
8ac65937
JH
1188 maxlen = strlen(committer) + msglen + 100;
1189 logrec = xmalloc(maxlen);
1190 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1191 sha1_to_hex(old_sha1),
1192 sha1_to_hex(new_sha1),
8ac65937
JH
1193 committer);
1194 if (msglen)
0ec29a47 1195 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1196 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1197 free(logrec);
91c8d590 1198 if (close(logfd) != 0 || written != len)
9a13f0b7 1199 return error("Unable to append to %s", log_file);
6de08ae6
SP
1200 return 0;
1201}
1202
c3b0dec5
LT
1203static int is_branch(const char *refname)
1204{
1205 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1206}
1207
4bd18c43
SP
1208int write_ref_sha1(struct ref_lock *lock,
1209 const unsigned char *sha1, const char *logmsg)
1210{
1211 static char term = '\n';
c3b0dec5 1212 struct object *o;
4bd18c43
SP
1213
1214 if (!lock)
95fc7512 1215 return -1;
a89fccd2 1216 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1217 unlock_ref(lock);
1218 return 0;
95fc7512 1219 }
c3b0dec5
LT
1220 o = parse_object(sha1);
1221 if (!o) {
1222 error("Trying to write ref %s with nonexistant object %s",
1223 lock->ref_name, sha1_to_hex(sha1));
1224 unlock_ref(lock);
1225 return -1;
1226 }
1227 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1228 error("Trying to write non-commit object %s to branch %s",
1229 sha1_to_hex(sha1), lock->ref_name);
1230 unlock_ref(lock);
1231 return -1;
1232 }
93822c22
AW
1233 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1234 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1235 || close_ref(lock) < 0) {
c33d5174 1236 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1237 unlock_ref(lock);
1238 return -1;
1239 }
5e290ff7 1240 invalidate_cached_refs();
bd104db1
NP
1241 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1242 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1243 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1244 unlock_ref(lock);
1245 return -1;
1246 }
605fac8b
NP
1247 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1248 /*
1249 * Special hack: If a branch is updated directly and HEAD
1250 * points to it (may happen on the remote side of a push
1251 * for example) then logically the HEAD reflog should be
1252 * updated too.
1253 * A generic solution implies reverse symref information,
1254 * but finding all symrefs pointing to the given branch
1255 * would be rather costly for this rare event (the direct
1256 * update of a branch) to be worth it. So let's cheat and
1257 * check with HEAD only which should cover 99% of all usage
1258 * scenarios (even 100% of the default ones).
1259 */
1260 unsigned char head_sha1[20];
1261 int head_flag;
1262 const char *head_ref;
1263 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1264 if (head_ref && (head_flag & REF_ISSYMREF) &&
1265 !strcmp(head_ref, lock->ref_name))
1266 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1267 }
b531394d 1268 if (commit_ref(lock)) {
434cd0cd 1269 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1270 unlock_ref(lock);
1271 return -1;
1272 }
4bd18c43
SP
1273 unlock_ref(lock);
1274 return 0;
95fc7512 1275}
d556fae2 1276
8b5157e4
NP
1277int create_symref(const char *ref_target, const char *refs_heads_master,
1278 const char *logmsg)
41b625b0
NP
1279{
1280 const char *lockpath;
1281 char ref[1000];
1282 int fd, len, written;
a4f34cbb 1283 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1284 unsigned char old_sha1[20], new_sha1[20];
1285
1286 if (logmsg && read_ref(ref_target, old_sha1))
1287 hashclr(old_sha1);
41b625b0 1288
d48744d1
JH
1289 if (safe_create_leading_directories(git_HEAD) < 0)
1290 return error("unable to create directory for %s", git_HEAD);
1291
41b625b0
NP
1292#ifndef NO_SYMLINK_HEAD
1293 if (prefer_symlink_refs) {
1294 unlink(git_HEAD);
1295 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1296 goto done;
41b625b0
NP
1297 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1298 }
1299#endif
1300
1301 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1302 if (sizeof(ref) <= len) {
1303 error("refname too long: %s", refs_heads_master);
47fc52e2 1304 goto error_free_return;
41b625b0
NP
1305 }
1306 lockpath = mkpath("%s.lock", git_HEAD);
1307 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1308 if (fd < 0) {
1309 error("Unable to open %s for writing", lockpath);
47fc52e2 1310 goto error_free_return;
41b625b0
NP
1311 }
1312 written = write_in_full(fd, ref, len);
91c8d590 1313 if (close(fd) != 0 || written != len) {
41b625b0 1314 error("Unable to write to %s", lockpath);
47fc52e2 1315 goto error_unlink_return;
41b625b0
NP
1316 }
1317 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1318 error("Unable to create %s", git_HEAD);
47fc52e2 1319 goto error_unlink_return;
41b625b0
NP
1320 }
1321 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1322 error("Unable to fix permissions on %s", lockpath);
47fc52e2
JH
1323 error_unlink_return:
1324 unlink(lockpath);
1325 error_free_return:
1326 free(git_HEAD);
1327 return -1;
41b625b0 1328 }
8b5157e4 1329
ee96d11b 1330#ifndef NO_SYMLINK_HEAD
8b5157e4 1331 done:
ee96d11b 1332#endif
8b5157e4
NP
1333 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1334 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1335
47fc52e2 1336 free(git_HEAD);
41b625b0
NP
1337 return 0;
1338}
1339
16d7cc90
JH
1340static char *ref_msg(const char *line, const char *endp)
1341{
1342 const char *ep;
16d7cc90 1343 line += 82;
182af834
PH
1344 ep = memchr(line, '\n', endp - line);
1345 if (!ep)
1346 ep = endp;
1347 return xmemdupz(line, ep - line);
16d7cc90
JH
1348}
1349
1350int 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 1351{
e5229042 1352 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1353 char *tz_c;
e29cb53a 1354 int logfd, tz, reccnt = 0;
d556fae2
SP
1355 struct stat st;
1356 unsigned long date;
e5229042 1357 unsigned char logged_sha1[20];
cb48cb58 1358 void *log_mapped;
dc49cd76 1359 size_t mapsz;
d556fae2
SP
1360
1361 logfile = git_path("logs/%s", ref);
1362 logfd = open(logfile, O_RDONLY, 0);
1363 if (logfd < 0)
1364 die("Unable to read log %s: %s", logfile, strerror(errno));
1365 fstat(logfd, &st);
1366 if (!st.st_size)
1367 die("Log %s is empty.", logfile);
dc49cd76
SP
1368 mapsz = xsize_t(st.st_size);
1369 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1370 logdata = log_mapped;
d556fae2
SP
1371 close(logfd);
1372
e5229042 1373 lastrec = NULL;
d556fae2
SP
1374 rec = logend = logdata + st.st_size;
1375 while (logdata < rec) {
e29cb53a 1376 reccnt++;
d556fae2
SP
1377 if (logdata < rec && *(rec-1) == '\n')
1378 rec--;
e5229042
SP
1379 lastgt = NULL;
1380 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1381 rec--;
e5229042
SP
1382 if (*rec == '>')
1383 lastgt = rec;
1384 }
1385 if (!lastgt)
d556fae2 1386 die("Log %s is corrupt.", logfile);
e5229042 1387 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1388 if (date <= at_time || cnt == 0) {
76a44c5c 1389 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1390 if (msg)
1391 *msg = ref_msg(rec, logend);
1392 if (cutoff_time)
1393 *cutoff_time = date;
1394 if (cutoff_tz)
1395 *cutoff_tz = tz;
1396 if (cutoff_cnt)
76a44c5c 1397 *cutoff_cnt = reccnt - 1;
e5229042
SP
1398 if (lastrec) {
1399 if (get_sha1_hex(lastrec, logged_sha1))
1400 die("Log %s is corrupt.", logfile);
1401 if (get_sha1_hex(rec + 41, sha1))
1402 die("Log %s is corrupt.", logfile);
a89fccd2 1403 if (hashcmp(logged_sha1, sha1)) {
e5229042
SP
1404 fprintf(stderr,
1405 "warning: Log %s has gap after %s.\n",
73013afd 1406 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1407 }
e5f38ec3
JH
1408 }
1409 else if (date == at_time) {
e5229042
SP
1410 if (get_sha1_hex(rec + 41, sha1))
1411 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1412 }
1413 else {
e5229042
SP
1414 if (get_sha1_hex(rec + 41, logged_sha1))
1415 die("Log %s is corrupt.", logfile);
a89fccd2 1416 if (hashcmp(logged_sha1, sha1)) {
e5229042
SP
1417 fprintf(stderr,
1418 "warning: Log %s unexpectedly ended on %s.\n",
73013afd 1419 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1420 }
1421 }
dc49cd76 1422 munmap(log_mapped, mapsz);
d556fae2
SP
1423 return 0;
1424 }
e5229042 1425 lastrec = rec;
ab2a1a32
JH
1426 if (cnt > 0)
1427 cnt--;
d556fae2
SP
1428 }
1429
e5229042
SP
1430 rec = logdata;
1431 while (rec < logend && *rec != '>' && *rec != '\n')
1432 rec++;
1433 if (rec == logend || *rec == '\n')
d556fae2 1434 die("Log %s is corrupt.", logfile);
e5229042 1435 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1436 tz = strtoul(tz_c, NULL, 10);
1437 if (get_sha1_hex(logdata, sha1))
1438 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1439 if (is_null_sha1(sha1)) {
1440 if (get_sha1_hex(logdata + 41, sha1))
1441 die("Log %s is corrupt.", logfile);
1442 }
16d7cc90
JH
1443 if (msg)
1444 *msg = ref_msg(logdata, logend);
dc49cd76 1445 munmap(log_mapped, mapsz);
16d7cc90
JH
1446
1447 if (cutoff_time)
1448 *cutoff_time = date;
1449 if (cutoff_tz)
1450 *cutoff_tz = tz;
1451 if (cutoff_cnt)
1452 *cutoff_cnt = reccnt;
1453 return 1;
d556fae2 1454}
2ff81662 1455
883d60fa 1456int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
2ff81662
JH
1457{
1458 const char *logfile;
1459 FILE *logfp;
1460 char buf[1024];
2266bf27 1461 int ret = 0;
2ff81662
JH
1462
1463 logfile = git_path("logs/%s", ref);
1464 logfp = fopen(logfile, "r");
1465 if (!logfp)
883d60fa 1466 return -1;
2ff81662
JH
1467 while (fgets(buf, sizeof(buf), logfp)) {
1468 unsigned char osha1[20], nsha1[20];
883d60fa
JS
1469 char *email_end, *message;
1470 unsigned long timestamp;
2266bf27 1471 int len, tz;
2ff81662
JH
1472
1473 /* old SP new SP name <email> SP time TAB msg LF */
1474 len = strlen(buf);
1475 if (len < 83 || buf[len-1] != '\n' ||
1476 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
883d60fa
JS
1477 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1478 !(email_end = strchr(buf + 82, '>')) ||
1479 email_end[1] != ' ' ||
1480 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1481 !message || message[0] != ' ' ||
1482 (message[1] != '+' && message[1] != '-') ||
1483 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 1484 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 1485 continue; /* corrupt? */
883d60fa
JS
1486 email_end[1] = '\0';
1487 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
1488 if (message[6] != '\t')
1489 message += 6;
1490 else
1491 message += 7;
883d60fa
JS
1492 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1493 if (ret)
2266bf27 1494 break;
2ff81662
JH
1495 }
1496 fclose(logfp);
2266bf27 1497 return ret;
2ff81662 1498}
e29cb53a 1499
eb8381c8
NP
1500static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1501{
1502 DIR *dir = opendir(git_path("logs/%s", base));
fcee5a14 1503 int retval = 0;
eb8381c8
NP
1504
1505 if (dir) {
1506 struct dirent *de;
1507 int baselen = strlen(base);
1508 char *log = xmalloc(baselen + 257);
1509
1510 memcpy(log, base, baselen);
1511 if (baselen && base[baselen-1] != '/')
1512 log[baselen++] = '/';
1513
1514 while ((de = readdir(dir)) != NULL) {
1515 struct stat st;
1516 int namelen;
1517
1518 if (de->d_name[0] == '.')
1519 continue;
1520 namelen = strlen(de->d_name);
1521 if (namelen > 255)
1522 continue;
1523 if (has_extension(de->d_name, ".lock"))
1524 continue;
1525 memcpy(log + baselen, de->d_name, namelen+1);
1526 if (stat(git_path("logs/%s", log), &st) < 0)
1527 continue;
1528 if (S_ISDIR(st.st_mode)) {
1529 retval = do_for_each_reflog(log, fn, cb_data);
1530 } else {
1531 unsigned char sha1[20];
1532 if (!resolve_ref(log, sha1, 0, NULL))
1533 retval = error("bad ref for %s", log);
1534 else
1535 retval = fn(log, sha1, 0, cb_data);
1536 }
1537 if (retval)
1538 break;
1539 }
1540 free(log);
1541 closedir(dir);
1542 }
acb39f64 1543 else if (*base)
fcee5a14 1544 return errno;
eb8381c8
NP
1545 return retval;
1546}
1547
1548int for_each_reflog(each_ref_fn fn, void *cb_data)
1549{
1550 return do_for_each_reflog("", fn, cb_data);
1551}
3d9f037c
CR
1552
1553int update_ref(const char *action, const char *refname,
1554 const unsigned char *sha1, const unsigned char *oldval,
1555 int flags, enum action_on_err onerr)
1556{
1557 static struct ref_lock *lock;
1558 lock = lock_any_ref_for_update(refname, oldval, flags);
1559 if (!lock) {
1560 const char *str = "Cannot lock the ref '%s'.";
1561 switch (onerr) {
1562 case MSG_ON_ERR: error(str, refname); break;
1563 case DIE_ON_ERR: die(str, refname); break;
1564 case QUIET_ON_ERR: break;
1565 }
1566 return 1;
1567 }
1568 if (write_ref_sha1(lock, sha1, action) < 0) {
1569 const char *str = "Cannot update the ref '%s'.";
1570 switch (onerr) {
1571 case MSG_ON_ERR: error(str, refname); break;
1572 case DIE_ON_ERR: die(str, refname); break;
1573 case QUIET_ON_ERR: break;
1574 }
1575 return 1;
1576 }
1577 return 0;
1578}
cda69f48
JK
1579
1580struct ref *find_ref_by_name(struct ref *list, const char *name)
1581{
1582 for ( ; list; list = list->next)
1583 if (!strcmp(list->name, name))
1584 return list;
1585 return NULL;
1586}