refs: store references hierarchically
[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
bc5fd6d3
MH
7/*
8 * Make sure "ref" is something reasonable to have under ".git/refs/";
9 * We do not like it if:
10 *
11 * - any path component of it begins with ".", or
12 * - it has double dots "..", or
13 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
14 * - it ends with a "/".
15 * - it ends with ".lock"
16 * - it contains a "\" (backslash)
17 */
f4204ab9 18
bc5fd6d3
MH
19/* Return true iff ch is not allowed in reference names. */
20static inline int bad_ref_char(int ch)
21{
22 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
23 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
24 return 1;
25 /* 2.13 Pattern Matching Notation */
26 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
27 return 1;
28 return 0;
29}
30
31/*
32 * Try to read one refname component from the front of refname. Return
33 * the length of the component found, or -1 if the component is not
34 * legal.
35 */
36static int check_refname_component(const char *refname, int flags)
37{
38 const char *cp;
39 char last = '\0';
40
41 for (cp = refname; ; cp++) {
42 char ch = *cp;
43 if (ch == '\0' || ch == '/')
44 break;
45 if (bad_ref_char(ch))
46 return -1; /* Illegal character in refname. */
47 if (last == '.' && ch == '.')
48 return -1; /* Refname contains "..". */
49 if (last == '@' && ch == '{')
50 return -1; /* Refname contains "@{". */
51 last = ch;
52 }
53 if (cp == refname)
dac529e4 54 return 0; /* Component has zero length. */
bc5fd6d3
MH
55 if (refname[0] == '.') {
56 if (!(flags & REFNAME_DOT_COMPONENT))
57 return -1; /* Component starts with '.'. */
58 /*
59 * Even if leading dots are allowed, don't allow "."
60 * as a component (".." is prevented by a rule above).
61 */
62 if (refname[1] == '\0')
63 return -1; /* Component equals ".". */
64 }
65 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
66 return -1; /* Refname ends with ".lock". */
67 return cp - refname;
68}
69
70int check_refname_format(const char *refname, int flags)
71{
72 int component_len, component_count = 0;
73
74 while (1) {
75 /* We are at the start of a path component. */
76 component_len = check_refname_component(refname, flags);
dac529e4 77 if (component_len <= 0) {
bc5fd6d3
MH
78 if ((flags & REFNAME_REFSPEC_PATTERN) &&
79 refname[0] == '*' &&
80 (refname[1] == '\0' || refname[1] == '/')) {
81 /* Accept one wildcard as a full refname component. */
82 flags &= ~REFNAME_REFSPEC_PATTERN;
83 component_len = 1;
84 } else {
85 return -1;
86 }
87 }
88 component_count++;
89 if (refname[component_len] == '\0')
90 break;
91 /* Skip to next component. */
92 refname += component_len + 1;
93 }
94
95 if (refname[component_len - 1] == '.')
96 return -1; /* Refname ends with '.'. */
97 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
98 return -1; /* Refname has only one component. */
99 return 0;
100}
101
102struct ref_entry;
e1e22e37 103
593f1bb8
MH
104struct ref_value {
105 unsigned char sha1[20];
106 unsigned char peeled[20];
107};
108
d3177275 109struct ref_dir {
e9c4c111 110 int nr, alloc;
e6ed3ca6
MH
111
112 /*
113 * Entries with index 0 <= i < sorted are sorted by name. New
114 * entries are appended to the list unsorted, and are sorted
115 * only when required; thus we avoid the need to sort the list
116 * after the addition of every reference.
117 */
118 int sorted;
119
d3177275 120 struct ref_entry **entries;
e9c4c111
JP
121};
122
432ad41e
MH
123/* ISSYMREF=0x01, ISPACKED=0x02, and ISBROKEN=0x04 are public interfaces */
124#define REF_KNOWS_PEELED 0x08
125#define REF_DIR 0x10
cf0adba7 126
432ad41e
MH
127/*
128 * A ref_entry represents either a reference or a "subdirectory" of
129 * references. Each directory in the reference namespace is
130 * represented by a ref_entry with (flags & REF_DIR) set and
131 * containing a subdir member that holds the entries in that
132 * directory. References are represented by a ref_entry with (flags &
133 * REF_DIR) unset and a value member that describes the reference's
134 * value. The flag member is at the ref_entry level, but it is also
135 * needed to interpret the contents of the value field (in other
136 * words, a ref_value object is not very much use without the
137 * enclosing ref_entry).
138 *
139 * Reference names cannot end with slash and directories' names are
140 * always stored with a trailing slash (except for the top-level
141 * directory, which is always denoted by ""). This has two nice
142 * consequences: (1) when the entries in each subdir are sorted
143 * lexicographically by name (as they usually are), the references in
144 * a whole tree can be generated in lexicographic order by traversing
145 * the tree in left-to-right, depth-first order; (2) the names of
146 * references and subdirectories cannot conflict, and therefore the
147 * presence of an empty subdirectory does not block the creation of a
148 * similarly-named reference. (The fact that reference names with the
149 * same leading components can conflict *with each other* is a
150 * separate issue that is regulated by is_refname_available().)
151 *
152 * Please note that the name field contains the fully-qualified
153 * reference (or subdirectory) name. Space could be saved by only
154 * storing the relative names. But that would require the full names
155 * to be generated on the fly when iterating in do_for_each_ref(), and
156 * would break callback functions, who have always been able to assume
157 * that the name strings that they are passed will not be freed during
158 * the iteration.
159 */
bc5fd6d3
MH
160struct ref_entry {
161 unsigned char flag; /* ISSYMREF? ISPACKED? */
593f1bb8 162 union {
432ad41e
MH
163 struct ref_value value; /* if not (flags&REF_DIR) */
164 struct ref_dir subdir; /* if (flags&REF_DIR) */
593f1bb8 165 } u;
432ad41e
MH
166 /*
167 * The full name of the reference (e.g., "refs/heads/master")
168 * or the full name of the directory with a trailing slash
169 * (e.g., "refs/heads/"):
170 */
bc5fd6d3
MH
171 char name[FLEX_ARRAY];
172};
e1e22e37 173
cddc4258
MH
174static struct ref_entry *create_ref_entry(const char *refname,
175 const unsigned char *sha1, int flag,
176 int check_name)
e1e22e37
LT
177{
178 int len;
cddc4258 179 struct ref_entry *ref;
e1e22e37 180
09116a1c 181 if (check_name &&
dfefa935
MH
182 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
183 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
184 len = strlen(refname) + 1;
185 ref = xmalloc(sizeof(struct ref_entry) + len);
593f1bb8
MH
186 hashcpy(ref->u.value.sha1, sha1);
187 hashclr(ref->u.value.peeled);
cddc4258
MH
188 memcpy(ref->name, refname, len);
189 ref->flag = flag;
190 return ref;
191}
192
432ad41e
MH
193static void clear_ref_dir(struct ref_dir *dir);
194
732134ed
MH
195static void free_ref_entry(struct ref_entry *entry)
196{
432ad41e
MH
197 if (entry->flag & REF_DIR)
198 clear_ref_dir(&entry->u.subdir);
732134ed
MH
199 free(entry);
200}
201
432ad41e
MH
202/*
203 * Add a ref_entry to the end of dir (unsorted). Entry is always
204 * stored directly in dir; no recursion into subdirectories is
205 * done.
206 */
207static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
cddc4258 208{
432ad41e
MH
209 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
210 dir->entries[dir->nr++] = entry;
c774aab9
JP
211}
212
432ad41e
MH
213/*
214 * Clear and free all entries in dir, recursively.
215 */
d3177275 216static void clear_ref_dir(struct ref_dir *dir)
bc5fd6d3
MH
217{
218 int i;
d3177275
MH
219 for (i = 0; i < dir->nr; i++)
220 free_ref_entry(dir->entries[i]);
221 free(dir->entries);
222 dir->sorted = dir->nr = dir->alloc = 0;
223 dir->entries = NULL;
bc5fd6d3
MH
224}
225
432ad41e
MH
226/*
227 * Create a struct ref_entry object for the specified dirname.
228 * dirname is the name of the directory with a trailing slash (e.g.,
229 * "refs/heads/") or "" for the top-level directory.
230 */
231static struct ref_entry *create_dir_entry(const char *dirname)
232{
233 struct ref_entry *direntry;
234 int len = strlen(dirname);
235 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
236 memcpy(direntry->name, dirname, len + 1);
237 direntry->flag = REF_DIR;
238 return direntry;
239}
240
e9c4c111 241static int ref_entry_cmp(const void *a, const void *b)
c774aab9 242{
e9c4c111
JP
243 struct ref_entry *one = *(struct ref_entry **)a;
244 struct ref_entry *two = *(struct ref_entry **)b;
245 return strcmp(one->name, two->name);
246}
c774aab9 247
d3177275 248static void sort_ref_dir(struct ref_dir *dir);
bc5fd6d3 249
432ad41e
MH
250/*
251 * Return the entry with the given refname from the ref_dir
252 * (non-recursively), sorting dir if necessary. Return NULL if no
253 * such entry is found.
254 */
d3177275 255static struct ref_entry *search_ref_dir(struct ref_dir *dir, const char *refname)
bc5fd6d3
MH
256{
257 struct ref_entry *e, **r;
258 int len;
259
432ad41e 260 if (refname == NULL || !dir->nr)
bc5fd6d3
MH
261 return NULL;
262
d3177275 263 sort_ref_dir(dir);
432ad41e 264
bc5fd6d3
MH
265 len = strlen(refname) + 1;
266 e = xmalloc(sizeof(struct ref_entry) + len);
267 memcpy(e->name, refname, len);
268
d3177275 269 r = bsearch(&e, dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
bc5fd6d3
MH
270
271 free(e);
272
273 if (r == NULL)
274 return NULL;
275
276 return *r;
277}
278
432ad41e
MH
279/*
280 * If refname is a reference name, find the ref_dir within the dir
281 * tree that should hold refname. If refname is a directory name
282 * (i.e., ends in '/'), then return that ref_dir itself. dir must
283 * represent the top-level directory. Sort ref_dirs and recurse into
284 * subdirectories as necessary. If mkdir is set, then create any
285 * missing directories; otherwise, return NULL if the desired
286 * directory cannot be found.
287 */
288static struct ref_dir *find_containing_dir(struct ref_dir *dir,
289 const char *refname, int mkdir)
290{
291 char *refname_copy = xstrdup(refname);
292 char *slash;
293 struct ref_entry *entry;
294 for (slash = strchr(refname_copy, '/'); slash; slash = strchr(slash + 1, '/')) {
295 char tmp = slash[1];
296 slash[1] = '\0';
297 entry = search_ref_dir(dir, refname_copy);
298 if (!entry) {
299 if (!mkdir) {
300 dir = NULL;
301 break;
302 }
303 entry = create_dir_entry(refname_copy);
304 add_entry_to_dir(dir, entry);
305 }
306 slash[1] = tmp;
307 assert(entry->flag & REF_DIR);
308 dir = &entry->u.subdir;
309 }
310
311 free(refname_copy);
312 return dir;
313}
314
315/*
316 * Find the value entry with the given name in dir, sorting ref_dirs
317 * and recursing into subdirectories as necessary. If the name is not
318 * found or it corresponds to a directory entry, return NULL.
319 */
320static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
321{
322 struct ref_entry *entry;
323 dir = find_containing_dir(dir, refname, 0);
324 if (!dir)
325 return NULL;
326 entry = search_ref_dir(dir, refname);
327 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
328}
329
330/*
331 * Add a ref_entry to the ref_dir (unsorted), recursing into
332 * subdirectories as necessary. dir must represent the top-level
333 * directory. Return 0 on success.
334 */
335static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
336{
337 dir = find_containing_dir(dir, ref->name, 1);
338 if (!dir)
339 return -1;
340 add_entry_to_dir(dir, ref);
341 return 0;
342}
343
202a56a9
MH
344/*
345 * Emit a warning and return true iff ref1 and ref2 have the same name
346 * and the same sha1. Die if they have the same name but different
347 * sha1s.
348 */
349static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
350{
432ad41e 351 if (strcmp(ref1->name, ref2->name))
202a56a9 352 return 0;
432ad41e
MH
353
354 /* Duplicate name; make sure that they don't conflict: */
355
356 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
357 /* This is impossible by construction */
358 die("Reference directory conflict: %s", ref1->name);
359
360 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
361 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
362
363 warning("Duplicated ref: %s", ref1->name);
364 return 1;
202a56a9
MH
365}
366
e6ed3ca6 367/*
432ad41e
MH
368 * Sort the entries in dir non-recursively (if they are not already
369 * sorted) and remove any duplicate entries.
e6ed3ca6 370 */
d3177275 371static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 372{
202a56a9 373 int i, j;
81a79d8e 374 struct ref_entry *last = NULL;
c774aab9 375
e6ed3ca6
MH
376 /*
377 * This check also prevents passing a zero-length array to qsort(),
378 * which is a problem on some platforms.
379 */
d3177275 380 if (dir->sorted == dir->nr)
e9c4c111 381 return;
c774aab9 382
d3177275 383 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 384
81a79d8e
MH
385 /* Remove any duplicates: */
386 for (i = 0, j = 0; j < dir->nr; j++) {
387 struct ref_entry *entry = dir->entries[j];
388 if (last && is_dup_ref(last, entry))
389 free_ref_entry(entry);
390 else
391 last = dir->entries[i++] = entry;
e9c4c111 392 }
81a79d8e 393 dir->sorted = dir->nr = i;
e9c4c111 394}
c774aab9 395
bc5fd6d3 396#define DO_FOR_EACH_INCLUDE_BROKEN 01
c774aab9 397
bc5fd6d3 398static struct ref_entry *current_ref;
c774aab9 399
bc5fd6d3
MH
400static int do_one_ref(const char *base, each_ref_fn fn, int trim,
401 int flags, void *cb_data, struct ref_entry *entry)
402{
429213e4 403 int retval;
bc5fd6d3
MH
404 if (prefixcmp(entry->name, base))
405 return 0;
c774aab9 406
bc5fd6d3
MH
407 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
408 if (entry->flag & REF_ISBROKEN)
409 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 410 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
411 error("%s does not point to a valid object!", entry->name);
412 return 0;
413 }
414 }
415 current_ref = entry;
593f1bb8 416 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
417 current_ref = NULL;
418 return retval;
bc5fd6d3 419}
c774aab9 420
c36b5bc2 421/*
d3177275 422 * Call fn for each reference in dir that has index in the range
432ad41e
MH
423 * offset <= index < dir->nr. Recurse into subdirectories that are in
424 * that index range, sorting them before iterating. This function
425 * does not sort dir itself; it should be sorted beforehand.
c36b5bc2 426 */
d3177275
MH
427static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
428 const char *base,
429 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
430{
431 int i;
d3177275
MH
432 assert(dir->sorted == dir->nr);
433 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
434 struct ref_entry *entry = dir->entries[i];
435 int retval;
436 if (entry->flag & REF_DIR) {
437 sort_ref_dir(&entry->u.subdir);
438 retval = do_for_each_ref_in_dir(&entry->u.subdir, 0,
439 base, fn, trim, flags, cb_data);
440 } else {
441 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
442 }
c36b5bc2
MH
443 if (retval)
444 return retval;
445 }
446 return 0;
447}
448
b3fd060f 449/*
d3177275 450 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
451 * by refname. Recurse into subdirectories. If a value entry appears
452 * in both dir1 and dir2, then only process the version that is in
453 * dir2. The input dirs must already be sorted, but subdirs will be
454 * sorted as needed.
b3fd060f 455 */
d3177275
MH
456static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
457 struct ref_dir *dir2,
458 const char *base, each_ref_fn fn, int trim,
459 int flags, void *cb_data)
b3fd060f
MH
460{
461 int retval;
462 int i1 = 0, i2 = 0;
463
d3177275
MH
464 assert(dir1->sorted == dir1->nr);
465 assert(dir2->sorted == dir2->nr);
432ad41e
MH
466 while (1) {
467 struct ref_entry *e1, *e2;
468 int cmp;
469 if (i1 == dir1->nr) {
470 return do_for_each_ref_in_dir(dir2, i2,
471 base, fn, trim, flags, cb_data);
472 }
473 if (i2 == dir2->nr) {
474 return do_for_each_ref_in_dir(dir1, i1,
475 base, fn, trim, flags, cb_data);
476 }
477 e1 = dir1->entries[i1];
478 e2 = dir2->entries[i2];
479 cmp = strcmp(e1->name, e2->name);
480 if (cmp == 0) {
481 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
482 /* Both are directories; descend them in parallel. */
483 sort_ref_dir(&e1->u.subdir);
484 sort_ref_dir(&e2->u.subdir);
485 retval = do_for_each_ref_in_dirs(
486 &e1->u.subdir, &e2->u.subdir,
487 base, fn, trim, flags, cb_data);
488 i1++;
489 i2++;
490 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
491 /* Both are references; ignore the one from dir1. */
492 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
493 i1++;
494 i2++;
495 } else {
496 die("conflict between reference and directory: %s",
497 e1->name);
498 }
b3fd060f 499 } else {
432ad41e
MH
500 struct ref_entry *e;
501 if (cmp < 0) {
502 e = e1;
b3fd060f 503 i1++;
432ad41e
MH
504 } else {
505 e = e2;
506 i2++;
507 }
508 if (e->flag & REF_DIR) {
509 sort_ref_dir(&e->u.subdir);
510 retval = do_for_each_ref_in_dir(
511 &e->u.subdir, 0,
512 base, fn, trim, flags, cb_data);
513 } else {
514 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
b3fd060f
MH
515 }
516 }
517 if (retval)
518 return retval;
519 }
d3177275
MH
520 if (i1 < dir1->nr)
521 return do_for_each_ref_in_dir(dir1, i1,
522 base, fn, trim, flags, cb_data);
523 if (i2 < dir2->nr)
524 return do_for_each_ref_in_dir(dir2, i2,
525 base, fn, trim, flags, cb_data);
b3fd060f
MH
526 return 0;
527}
528
d66da478
MH
529/*
530 * Return true iff refname1 and refname2 conflict with each other.
531 * Two reference names conflict if one of them exactly matches the
532 * leading components of the other; e.g., "foo/bar" conflicts with
533 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
534 * "foo/barbados".
535 */
536static int names_conflict(const char *refname1, const char *refname2)
537{
5a4d4947
MH
538 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
539 ;
540 return (*refname1 == '\0' && *refname2 == '/')
541 || (*refname1 == '/' && *refname2 == '\0');
542}
543
544struct name_conflict_cb {
545 const char *refname;
546 const char *oldrefname;
547 const char *conflicting_refname;
548};
549
550static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
551 int flags, void *cb_data)
552{
553 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
554 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
555 return 0;
556 if (names_conflict(data->refname, existingrefname)) {
557 data->conflicting_refname = existingrefname;
558 return 1;
d66da478 559 }
5a4d4947 560 return 0;
d66da478
MH
561}
562
bc5fd6d3
MH
563/*
564 * Return true iff a reference named refname could be created without
5a4d4947
MH
565 * conflicting with the name of an existing reference in array. If
566 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
567 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
568 * operation).
569 */
570static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 571 struct ref_dir *dir)
bc5fd6d3 572{
5a4d4947
MH
573 struct name_conflict_cb data;
574 data.refname = refname;
575 data.oldrefname = oldrefname;
576 data.conflicting_refname = NULL;
577
d3177275
MH
578 sort_ref_dir(dir);
579 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
580 0, DO_FOR_EACH_INCLUDE_BROKEN,
581 &data)) {
5a4d4947
MH
582 error("'%s' exists; cannot create '%s'",
583 data.conflicting_refname, refname);
584 return 0;
bc5fd6d3
MH
585 }
586 return 1;
e1e22e37
LT
587}
588
5e290ff7
JH
589/*
590 * Future: need to be in "struct repository"
591 * when doing a full libification.
592 */
79c7ca54
MH
593static struct ref_cache {
594 struct ref_cache *next;
5e290ff7
JH
595 char did_loose;
596 char did_packed;
d3177275
MH
597 struct ref_dir loose;
598 struct ref_dir packed;
ce40979c
MH
599 /* The submodule name, or "" for the main repo. */
600 char name[FLEX_ARRAY];
79c7ca54 601} *ref_cache;
0e88c130 602
760c4512 603static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 604{
1b7edaf9 605 if (refs->did_packed)
d3177275 606 clear_ref_dir(&refs->packed);
760c4512 607 refs->did_packed = 0;
5e290ff7 608}
e1e22e37 609
760c4512
MH
610static void clear_loose_ref_cache(struct ref_cache *refs)
611{
612 if (refs->did_loose)
d3177275 613 clear_ref_dir(&refs->loose);
760c4512
MH
614 refs->did_loose = 0;
615}
616
79c7ca54 617static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 618{
ce40979c 619 int len;
79c7ca54 620 struct ref_cache *refs;
ce40979c
MH
621 if (!submodule)
622 submodule = "";
623 len = strlen(submodule) + 1;
79c7ca54 624 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 625 memcpy(refs->name, submodule, len);
e5dbf605
MH
626 return refs;
627}
628
4349a668 629/*
79c7ca54 630 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
631 * the main repository, use submodule==NULL. The returned structure
632 * will be allocated and initialized but not necessarily populated; it
633 * should not be freed.
634 */
79c7ca54 635static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 636{
79c7ca54 637 struct ref_cache *refs = ref_cache;
0e88c130
MH
638 if (!submodule)
639 submodule = "";
640 while (refs) {
641 if (!strcmp(submodule, refs->name))
642 return refs;
643 refs = refs->next;
4349a668 644 }
0e88c130 645
79c7ca54
MH
646 refs = create_ref_cache(submodule);
647 refs->next = ref_cache;
648 ref_cache = refs;
0e88c130 649 return refs;
4349a668
MH
650}
651
8be8bde7 652void invalidate_ref_cache(const char *submodule)
f130b116 653{
c5f29abd
MH
654 struct ref_cache *refs = get_ref_cache(submodule);
655 clear_packed_ref_cache(refs);
656 clear_loose_ref_cache(refs);
5e290ff7 657}
e1e22e37 658
bc5fd6d3
MH
659/*
660 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
661 * Return a pointer to the refname within the line (null-terminated),
662 * or NULL if there was a problem.
663 */
664static const char *parse_ref_line(char *line, unsigned char *sha1)
665{
666 /*
667 * 42: the answer to everything.
668 *
669 * In this case, it happens to be the answer to
670 * 40 (length of sha1 hex representation)
671 * +1 (space in between hex and name)
672 * +1 (newline at the end of the line)
673 */
674 int len = strlen(line) - 42;
675
676 if (len <= 0)
677 return NULL;
678 if (get_sha1_hex(line, sha1) < 0)
679 return NULL;
680 if (!isspace(line[40]))
681 return NULL;
682 line += 41;
683 if (isspace(*line))
684 return NULL;
685 if (line[len] != '\n')
686 return NULL;
687 line[len] = 0;
688
689 return line;
690}
691
d3177275 692static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 693{
e9c4c111 694 struct ref_entry *last = NULL;
f4204ab9
JH
695 char refline[PATH_MAX];
696 int flag = REF_ISPACKED;
697
698 while (fgets(refline, sizeof(refline), f)) {
699 unsigned char sha1[20];
dfefa935 700 const char *refname;
f4204ab9
JH
701 static const char header[] = "# pack-refs with:";
702
703 if (!strncmp(refline, header, sizeof(header)-1)) {
704 const char *traits = refline + sizeof(header) - 1;
705 if (strstr(traits, " peeled "))
706 flag |= REF_KNOWS_PEELED;
707 /* perhaps other traits later as well */
708 continue;
709 }
710
dfefa935
MH
711 refname = parse_ref_line(refline, sha1);
712 if (refname) {
dd73ecd1 713 last = create_ref_entry(refname, sha1, flag, 1);
d3177275 714 add_ref(dir, last);
f4204ab9
JH
715 continue;
716 }
717 if (last &&
718 refline[0] == '^' &&
719 strlen(refline) == 42 &&
720 refline[41] == '\n' &&
721 !get_sha1_hex(refline + 1, sha1))
593f1bb8 722 hashcpy(last->u.value.peeled, sha1);
f4204ab9 723 }
f4204ab9
JH
724}
725
d3177275 726static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 727{
4349a668
MH
728 if (!refs->did_packed) {
729 const char *packed_refs_file;
730 FILE *f;
0bad611b 731
316b097a
MH
732 if (*refs->name)
733 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
734 else
735 packed_refs_file = git_path("packed-refs");
736 f = fopen(packed_refs_file, "r");
e1e22e37 737 if (f) {
2c5c66be 738 read_packed_refs(f, &refs->packed);
e1e22e37 739 fclose(f);
e1e22e37 740 }
0bad611b 741 refs->did_packed = 1;
e1e22e37 742 }
e9c4c111 743 return &refs->packed;
e1e22e37
LT
744}
745
30249ee6
MH
746void add_packed_ref(const char *refname, const unsigned char *sha1)
747{
748 add_ref(get_packed_refs(get_ref_cache(NULL)),
749 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
750}
751
3b124823 752static void get_ref_dir(struct ref_cache *refs, const char *base,
d3177275 753 struct ref_dir *dir)
e1e22e37 754{
d3177275 755 DIR *d;
0bad611b
HV
756 const char *path;
757
3b124823
MH
758 if (*refs->name)
759 path = git_path_submodule(refs->name, "%s", base);
0bad611b
HV
760 else
761 path = git_path("%s", base);
762
d3177275
MH
763 d = opendir(path);
764 if (d) {
e1e22e37
LT
765 struct dirent *de;
766 int baselen = strlen(base);
dfefa935 767 char *refname = xmalloc(baselen + 257);
e1e22e37 768
dfefa935 769 memcpy(refname, base, baselen);
e1e22e37 770 if (baselen && base[baselen-1] != '/')
dfefa935 771 refname[baselen++] = '/';
e1e22e37 772
d3177275 773 while ((de = readdir(d)) != NULL) {
e1e22e37
LT
774 unsigned char sha1[20];
775 struct stat st;
8da19775 776 int flag;
e1e22e37 777 int namelen;
0bad611b 778 const char *refdir;
e1e22e37
LT
779
780 if (de->d_name[0] == '.')
781 continue;
782 namelen = strlen(de->d_name);
783 if (namelen > 255)
784 continue;
785 if (has_extension(de->d_name, ".lock"))
786 continue;
dfefa935 787 memcpy(refname + baselen, de->d_name, namelen+1);
3b124823
MH
788 refdir = *refs->name
789 ? git_path_submodule(refs->name, "%s", refname)
dfefa935 790 : git_path("%s", refname);
0bad611b 791 if (stat(refdir, &st) < 0)
e1e22e37
LT
792 continue;
793 if (S_ISDIR(st.st_mode)) {
d3177275 794 get_ref_dir(refs, refname, dir);
e1e22e37
LT
795 continue;
796 }
3b124823 797 if (*refs->name) {
f8948e2f 798 hashclr(sha1);
0bad611b 799 flag = 0;
3b124823 800 if (resolve_gitlink_ref(refs->name, refname, sha1) < 0) {
0bad611b 801 hashclr(sha1);
98ac34b2 802 flag |= REF_ISBROKEN;
0bad611b 803 }
dfefa935 804 } else if (read_ref_full(refname, sha1, 1, &flag)) {
09116a1c
JH
805 hashclr(sha1);
806 flag |= REF_ISBROKEN;
807 }
d3177275 808 add_ref(dir, create_ref_entry(refname, sha1, flag, 1));
e1e22e37 809 }
dfefa935 810 free(refname);
d3177275 811 closedir(d);
e1e22e37 812 }
e1e22e37
LT
813}
814
d3177275 815static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 816{
4349a668 817 if (!refs->did_loose) {
3b124823 818 get_ref_dir(refs, "refs", &refs->loose);
4349a668 819 refs->did_loose = 1;
e1e22e37 820 }
2c5c66be 821 return &refs->loose;
e1e22e37
LT
822}
823
ca8db142
LT
824/* We allow "recursive" symbolic refs. Only within reason, though */
825#define MAXDEPTH 5
0ebde32c
LT
826#define MAXREFLEN (1024)
827
e5fa45c1
JH
828/*
829 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
830 * from the loose refs in ref_cache refs. Find <refname> in the
831 * packed-refs file for the submodule.
e5fa45c1 832 */
b0626608 833static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 834 const char *refname, unsigned char *sha1)
0ebde32c 835{
2c5c66be 836 struct ref_entry *ref;
d3177275 837 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 838
432ad41e 839 ref = find_ref(dir, refname);
b0626608
MH
840 if (ref == NULL)
841 return -1;
842
593f1bb8 843 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 844 return 0;
0ebde32c
LT
845}
846
b0626608 847static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 848 const char *refname, unsigned char *sha1,
dfefa935 849 int recursion)
0ebde32c 850{
064d51dc 851 int fd, len;
0ebde32c 852 char buffer[128], *p;
064d51dc 853 char *path;
0ebde32c 854
064d51dc 855 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 856 return -1;
064d51dc
MH
857 path = *refs->name
858 ? git_path_submodule(refs->name, "%s", refname)
859 : git_path("%s", refname);
860 fd = open(path, O_RDONLY);
0ebde32c 861 if (fd < 0)
b0626608 862 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
863
864 len = read(fd, buffer, sizeof(buffer)-1);
865 close(fd);
866 if (len < 0)
867 return -1;
868 while (len && isspace(buffer[len-1]))
869 len--;
870 buffer[len] = 0;
871
872 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 873 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
874 return 0;
875
876 /* Symref? */
877 if (strncmp(buffer, "ref:", 4))
878 return -1;
879 p = buffer + 4;
880 while (isspace(*p))
881 p++;
882
064d51dc 883 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
884}
885
85be1fe3 886int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
887{
888 int len = strlen(path), retval;
064d51dc 889 char *submodule;
b0626608 890 struct ref_cache *refs;
0ebde32c
LT
891
892 while (len && path[len-1] == '/')
893 len--;
894 if (!len)
895 return -1;
b0626608
MH
896 submodule = xstrndup(path, len);
897 refs = get_ref_cache(submodule);
898 free(submodule);
899
064d51dc 900 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
901 return retval;
902}
ca8db142 903
4886b89f 904/*
c224ca7f
MH
905 * Try to read ref from the packed references. On success, set sha1
906 * and return 0; otherwise, return -1.
4886b89f 907 */
dfefa935 908static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 909{
d3177275 910 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 911 struct ref_entry *entry = find_ref(packed, refname);
2c5c66be 912 if (entry) {
593f1bb8 913 hashcpy(sha1, entry->u.value.sha1);
2c5c66be 914 return 0;
c224ca7f
MH
915 }
916 return -1;
917}
918
8d68493f 919const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 920{
0104ca09
HO
921 int depth = MAXDEPTH;
922 ssize_t len;
a876ed83 923 char buffer[256];
dfefa935 924 static char refname_buffer[256];
ca8db142 925
8da19775
JH
926 if (flag)
927 *flag = 0;
928
dfefa935 929 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
930 return NULL;
931
a876ed83 932 for (;;) {
55956350 933 char path[PATH_MAX];
a876ed83
JH
934 struct stat st;
935 char *buf;
936 int fd;
8a65ff76 937
a876ed83
JH
938 if (--depth < 0)
939 return NULL;
ca8db142 940
dfefa935 941 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 942
a876ed83 943 if (lstat(path, &st) < 0) {
c224ca7f
MH
944 if (errno != ENOENT)
945 return NULL;
946 /*
947 * The loose reference file does not exist;
948 * check for a packed reference.
949 */
dfefa935 950 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
951 if (flag)
952 *flag |= REF_ISPACKED;
dfefa935 953 return refname;
434cd0cd 954 }
c224ca7f
MH
955 /* The reference is not a packed reference, either. */
956 if (reading) {
a876ed83 957 return NULL;
c224ca7f
MH
958 } else {
959 hashclr(sha1);
dfefa935 960 return refname;
c224ca7f 961 }
a876ed83 962 }
ca8db142 963
a876ed83
JH
964 /* Follow "normalized" - ie "refs/.." symlinks by hand */
965 if (S_ISLNK(st.st_mode)) {
966 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
967 if (len < 0)
968 return NULL;
b54cb795 969 buffer[len] = 0;
1f58a038
MH
970 if (!prefixcmp(buffer, "refs/") &&
971 !check_refname_format(buffer, 0)) {
dfefa935
MH
972 strcpy(refname_buffer, buffer);
973 refname = refname_buffer;
8da19775
JH
974 if (flag)
975 *flag |= REF_ISSYMREF;
a876ed83
JH
976 continue;
977 }
ca8db142 978 }
a876ed83 979
7a21632f
DS
980 /* Is it a directory? */
981 if (S_ISDIR(st.st_mode)) {
982 errno = EISDIR;
983 return NULL;
984 }
985
a876ed83
JH
986 /*
987 * Anything else, just open it and try to use it as
988 * a ref
989 */
990 fd = open(path, O_RDONLY);
991 if (fd < 0)
992 return NULL;
93d26e4c 993 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 994 close(fd);
28775050
MH
995 if (len < 0)
996 return NULL;
997 while (len && isspace(buffer[len-1]))
998 len--;
999 buffer[len] = '\0';
a876ed83
JH
1000
1001 /*
1002 * Is it a symbolic ref?
1003 */
28775050 1004 if (prefixcmp(buffer, "ref:"))
a876ed83 1005 break;
55956350
JH
1006 if (flag)
1007 *flag |= REF_ISSYMREF;
a876ed83 1008 buf = buffer + 4;
28775050
MH
1009 while (isspace(*buf))
1010 buf++;
313fb010 1011 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1012 if (flag)
1013 *flag |= REF_ISBROKEN;
313fb010
MH
1014 return NULL;
1015 }
dfefa935 1016 refname = strcpy(refname_buffer, buf);
8a65ff76 1017 }
f989fea0
MH
1018 /* Please note that FETCH_HEAD has a second line containing other data. */
1019 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1020 if (flag)
1021 *flag |= REF_ISBROKEN;
a876ed83 1022 return NULL;
629cd3ac 1023 }
dfefa935 1024 return refname;
a876ed83
JH
1025}
1026
96ec7b1e
NTND
1027char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1028{
8cad4744 1029 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1030 return ret ? xstrdup(ret) : NULL;
1031}
1032
d08bae7e
IL
1033/* The argument to filter_refs */
1034struct ref_filter {
1035 const char *pattern;
1036 each_ref_fn *fn;
1037 void *cb_data;
1038};
1039
dfefa935 1040int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1041{
8d68493f 1042 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1043 return 0;
1044 return -1;
8a65ff76
LT
1045}
1046
dfefa935 1047int read_ref(const char *refname, unsigned char *sha1)
c6893323 1048{
dfefa935 1049 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1050}
1051
bc5fd6d3 1052int ref_exists(const char *refname)
ef06b918 1053{
bc5fd6d3
MH
1054 unsigned char sha1[20];
1055 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1056}
1057
85be1fe3 1058static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1059 void *data)
d08bae7e
IL
1060{
1061 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1062 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1063 return 0;
85be1fe3 1064 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1065}
1066
dfefa935 1067int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1068{
1069 int flag;
1070 unsigned char base[20];
1071 struct object *o;
1072
dfefa935
MH
1073 if (current_ref && (current_ref->name == refname
1074 || !strcmp(current_ref->name, refname))) {
0ae91be0 1075 if (current_ref->flag & REF_KNOWS_PEELED) {
593f1bb8 1076 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
1077 return 0;
1078 }
593f1bb8 1079 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
1080 goto fallback;
1081 }
1082
dfefa935 1083 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1084 return -1;
1085
1086 if ((flag & REF_ISPACKED)) {
d3177275 1087 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
432ad41e 1088 struct ref_entry *r = find_ref(dir, refname);
cf0adba7 1089
e9c4c111 1090 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
593f1bb8 1091 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1092 return 0;
cf0adba7 1093 }
cf0adba7
JH
1094 }
1095
0ae91be0 1096fallback:
cf0adba7 1097 o = parse_object(base);
8c87dc77 1098 if (o && o->type == OBJ_TAG) {
dfefa935 1099 o = deref_tag(o, refname, 0);
cf0adba7
JH
1100 if (o) {
1101 hashcpy(sha1, o->sha1);
1102 return 0;
1103 }
1104 }
1105 return -1;
1106}
1107
bc5fd6d3
MH
1108struct warn_if_dangling_data {
1109 FILE *fp;
1110 const char *refname;
1111 const char *msg_fmt;
1112};
1113
1114static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1115 int flags, void *cb_data)
1116{
1117 struct warn_if_dangling_data *d = cb_data;
1118 const char *resolves_to;
1119 unsigned char junk[20];
1120
1121 if (!(flags & REF_ISSYMREF))
1122 return 0;
1123
1124 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1125 if (!resolves_to || strcmp(resolves_to, d->refname))
1126 return 0;
1127
1128 fprintf(d->fp, d->msg_fmt, refname);
1129 return 0;
1130}
1131
1132void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1133{
1134 struct warn_if_dangling_data data;
1135
1136 data.fp = fp;
1137 data.refname = refname;
1138 data.msg_fmt = msg_fmt;
1139 for_each_rawref(warn_if_dangling_symref, &data);
1140}
1141
0bad611b
HV
1142static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1143 int trim, int flags, void *cb_data)
8a65ff76 1144{
316b097a 1145 struct ref_cache *refs = get_ref_cache(submodule);
d3177275
MH
1146 struct ref_dir *packed_refs = get_packed_refs(refs);
1147 struct ref_dir *loose_refs = get_loose_refs(refs);
1148 sort_ref_dir(packed_refs);
1149 sort_ref_dir(loose_refs);
1150 return do_for_each_ref_in_dirs(packed_refs,
1151 loose_refs,
1152 base, fn, trim, flags, cb_data);
8a65ff76
LT
1153}
1154
0bad611b 1155static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1156{
1157 unsigned char sha1[20];
8da19775
JH
1158 int flag;
1159
0bad611b
HV
1160 if (submodule) {
1161 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1162 return fn("HEAD", sha1, 0, cb_data);
1163
1164 return 0;
1165 }
1166
c6893323 1167 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1168 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1169
2f34ba32 1170 return 0;
723c31fe
LT
1171}
1172
0bad611b
HV
1173int head_ref(each_ref_fn fn, void *cb_data)
1174{
1175 return do_head_ref(NULL, fn, cb_data);
1176}
1177
9ef6aeb0
HV
1178int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1179{
1180 return do_head_ref(submodule, fn, cb_data);
1181}
1182
cb5d709f 1183int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1184{
b3cfc406 1185 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1186}
1187
9ef6aeb0
HV
1188int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1189{
b3cfc406 1190 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1191}
1192
2a8177b6
CC
1193int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1194{
0bad611b 1195 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1196}
1197
9ef6aeb0
HV
1198int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1199 each_ref_fn fn, void *cb_data)
1200{
1201 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1202}
1203
cb5d709f 1204int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1205{
2a8177b6 1206 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1207}
1208
9ef6aeb0
HV
1209int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1210{
1211 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1212}
1213
cb5d709f 1214int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1215{
2a8177b6 1216 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1217}
1218
9ef6aeb0
HV
1219int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1220{
1221 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1222}
1223
cb5d709f 1224int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1225{
2a8177b6 1226 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1227}
1228
9ef6aeb0
HV
1229int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1230{
1231 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1232}
1233
29268700
CC
1234int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1235{
0bad611b 1236 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1237}
1238
a1bea2c1
JT
1239int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1240{
1241 struct strbuf buf = STRBUF_INIT;
1242 int ret = 0;
1243 unsigned char sha1[20];
1244 int flag;
1245
1246 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1247 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1248 ret = fn(buf.buf, sha1, flag, cb_data);
1249 strbuf_release(&buf);
1250
1251 return ret;
1252}
1253
1254int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1255{
1256 struct strbuf buf = STRBUF_INIT;
1257 int ret;
1258 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1259 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1260 strbuf_release(&buf);
1261 return ret;
1262}
1263
b09fe971
IL
1264int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1265 const char *prefix, void *cb_data)
d08bae7e
IL
1266{
1267 struct strbuf real_pattern = STRBUF_INIT;
1268 struct ref_filter filter;
d08bae7e
IL
1269 int ret;
1270
b09fe971 1271 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1272 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1273 else if (prefix)
1274 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1275 strbuf_addstr(&real_pattern, pattern);
1276
894a9d33 1277 if (!has_glob_specials(pattern)) {
9517e6b8 1278 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1279 if (real_pattern.buf[real_pattern.len - 1] != '/')
1280 strbuf_addch(&real_pattern, '/');
1281 /* No need to check for '*', there is none. */
1282 strbuf_addch(&real_pattern, '*');
1283 }
1284
1285 filter.pattern = real_pattern.buf;
1286 filter.fn = fn;
1287 filter.cb_data = cb_data;
1288 ret = for_each_ref(filter_refs, &filter);
1289
1290 strbuf_release(&real_pattern);
1291 return ret;
1292}
1293
b09fe971
IL
1294int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1295{
1296 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1297}
1298
f8948e2f
JH
1299int for_each_rawref(each_ref_fn fn, void *cb_data)
1300{
b3cfc406 1301 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1302 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1303}
1304
4577e483 1305const char *prettify_refname(const char *name)
a9c37a72 1306{
a9c37a72
DB
1307 return name + (
1308 !prefixcmp(name, "refs/heads/") ? 11 :
1309 !prefixcmp(name, "refs/tags/") ? 10 :
1310 !prefixcmp(name, "refs/remotes/") ? 13 :
1311 0);
1312}
1313
79803322
SP
1314const char *ref_rev_parse_rules[] = {
1315 "%.*s",
1316 "refs/%.*s",
1317 "refs/tags/%.*s",
1318 "refs/heads/%.*s",
1319 "refs/remotes/%.*s",
1320 "refs/remotes/%.*s/HEAD",
1321 NULL
1322};
1323
1324int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1325{
1326 const char **p;
1327 const int abbrev_name_len = strlen(abbrev_name);
1328
1329 for (p = rules; *p; p++) {
1330 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1331 return 1;
1332 }
1333 }
1334
1335 return 0;
1336}
1337
e5f38ec3 1338static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1339 const unsigned char *old_sha1, int mustexist)
1340{
c6893323 1341 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1342 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1343 unlock_ref(lock);
1344 return NULL;
1345 }
a89fccd2 1346 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1347 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1348 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1349 unlock_ref(lock);
1350 return NULL;
1351 }
1352 return lock;
1353}
1354
7155b727 1355static int remove_empty_directories(const char *file)
bc7127ef
JH
1356{
1357 /* we want to create a file but there is a directory there;
1358 * if that is an empty directory (or a directory that contains
1359 * only empty directories), remove them.
1360 */
7155b727
JS
1361 struct strbuf path;
1362 int result;
bc7127ef 1363
7155b727
JS
1364 strbuf_init(&path, 20);
1365 strbuf_addstr(&path, file);
1366
a0f4afbe 1367 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1368
1369 strbuf_release(&path);
1370
1371 return result;
bc7127ef
JH
1372}
1373
ff74f7f1
JH
1374/*
1375 * *string and *len will only be substituted, and *string returned (for
1376 * later free()ing) if the string passed in is a magic short-hand form
1377 * to name a branch.
1378 */
1379static char *substitute_branch_name(const char **string, int *len)
1380{
1381 struct strbuf buf = STRBUF_INIT;
1382 int ret = interpret_branch_name(*string, &buf);
1383
1384 if (ret == *len) {
1385 size_t size;
1386 *string = strbuf_detach(&buf, &size);
1387 *len = size;
1388 return (char *)*string;
1389 }
1390
1391 return NULL;
1392}
1393
1394int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1395{
1396 char *last_branch = substitute_branch_name(&str, &len);
1397 const char **p, *r;
1398 int refs_found = 0;
1399
1400 *ref = NULL;
1401 for (p = ref_rev_parse_rules; *p; p++) {
1402 char fullref[PATH_MAX];
1403 unsigned char sha1_from_ref[20];
1404 unsigned char *this_result;
1405 int flag;
1406
1407 this_result = refs_found ? sha1_from_ref : sha1;
1408 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1409 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1410 if (r) {
1411 if (!refs_found++)
1412 *ref = xstrdup(r);
1413 if (!warn_ambiguous_refs)
1414 break;
55956350 1415 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1416 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1417 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1418 warning("ignoring broken ref %s.", fullref);
1419 }
ff74f7f1
JH
1420 }
1421 free(last_branch);
1422 return refs_found;
1423}
1424
1425int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1426{
1427 char *last_branch = substitute_branch_name(&str, &len);
1428 const char **p;
1429 int logs_found = 0;
1430
1431 *log = NULL;
1432 for (p = ref_rev_parse_rules; *p; p++) {
1433 struct stat st;
1434 unsigned char hash[20];
1435 char path[PATH_MAX];
1436 const char *ref, *it;
1437
1438 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1439 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1440 if (!ref)
1441 continue;
1442 if (!stat(git_path("logs/%s", path), &st) &&
1443 S_ISREG(st.st_mode))
1444 it = path;
1445 else if (strcmp(ref, path) &&
1446 !stat(git_path("logs/%s", ref), &st) &&
1447 S_ISREG(st.st_mode))
1448 it = ref;
1449 else
1450 continue;
1451 if (!logs_found++) {
1452 *log = xstrdup(it);
1453 hashcpy(sha1, hash);
1454 }
1455 if (!warn_ambiguous_refs)
1456 break;
1457 }
1458 free(last_branch);
1459 return logs_found;
1460}
1461
dfefa935
MH
1462static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1463 const unsigned char *old_sha1,
1464 int flags, int *type_p)
4bd18c43 1465{
434cd0cd 1466 char *ref_file;
dfefa935 1467 const char *orig_refname = refname;
4bd18c43 1468 struct ref_lock *lock;
5cc3cef9 1469 int last_errno = 0;
acd3b9ec 1470 int type, lflags;
4431fcc4 1471 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1472 int missing = 0;
4bd18c43
SP
1473
1474 lock = xcalloc(1, sizeof(struct ref_lock));
1475 lock->lock_fd = -1;
1476
8d68493f 1477 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1478 if (!refname && errno == EISDIR) {
bc7127ef
JH
1479 /* we are trying to lock foo but we used to
1480 * have foo/bar which now does not exist;
1481 * it is normal for the empty directory 'foo'
1482 * to remain.
1483 */
dfefa935 1484 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1485 if (remove_empty_directories(ref_file)) {
1486 last_errno = errno;
dfefa935 1487 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1488 goto error_return;
1489 }
8d68493f 1490 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1491 }
68db31cc
SV
1492 if (type_p)
1493 *type_p = type;
dfefa935 1494 if (!refname) {
5cc3cef9 1495 last_errno = errno;
818f477c 1496 error("unable to resolve reference %s: %s",
dfefa935 1497 orig_refname, strerror(errno));
5cc3cef9 1498 goto error_return;
4bd18c43 1499 }
5bdd8d4a 1500 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1501 /* When the ref did not exist and we are creating it,
1502 * make sure there is no existing ref that is packed
1503 * whose name begins with our refname, nor a ref whose
1504 * name is a proper prefix of our refname.
1505 */
5bdd8d4a 1506 if (missing &&
316b097a 1507 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1508 last_errno = ENOTDIR;
c976d415 1509 goto error_return;
f475e08e 1510 }
22a3844e 1511
c33d5174 1512 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1513
acd3b9ec
JH
1514 lflags = LOCK_DIE_ON_ERROR;
1515 if (flags & REF_NODEREF) {
dfefa935 1516 refname = orig_refname;
acd3b9ec
JH
1517 lflags |= LOCK_NODEREF;
1518 }
dfefa935
MH
1519 lock->ref_name = xstrdup(refname);
1520 lock->orig_ref_name = xstrdup(orig_refname);
1521 ref_file = git_path("%s", refname);
5bdd8d4a 1522 if (missing)
68db31cc
SV
1523 lock->force_write = 1;
1524 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1525 lock->force_write = 1;
4bd18c43 1526
5cc3cef9
JH
1527 if (safe_create_leading_directories(ref_file)) {
1528 last_errno = errno;
1529 error("unable to create directory for %s", ref_file);
1530 goto error_return;
1531 }
4bd18c43 1532
acd3b9ec 1533 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1534 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1535
1536 error_return:
1537 unlock_ref(lock);
1538 errno = last_errno;
1539 return NULL;
4bd18c43
SP
1540}
1541
dfefa935 1542struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1543{
53cce84c 1544 char refpath[PATH_MAX];
dfefa935 1545 if (check_refname_format(refname, 0))
4bd18c43 1546 return NULL;
dfefa935 1547 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1548 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1549}
1550
dfefa935
MH
1551struct ref_lock *lock_any_ref_for_update(const char *refname,
1552 const unsigned char *old_sha1, int flags)
4bd18c43 1553{
dfefa935 1554 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1555 return NULL;
dfefa935 1556 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1557}
1558
d66da478
MH
1559struct repack_without_ref_sb {
1560 const char *refname;
1561 int fd;
1562};
1563
1564static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1565 int flags, void *cb_data)
1566{
1567 struct repack_without_ref_sb *data = cb_data;
1568 char line[PATH_MAX + 100];
1569 int len;
1570
1571 if (!strcmp(data->refname, refname))
1572 return 0;
1573 len = snprintf(line, sizeof(line), "%s %s\n",
1574 sha1_to_hex(sha1), refname);
1575 /* this should not happen but just being defensive */
1576 if (len > sizeof(line))
1577 die("too long a refname '%s'", refname);
1578 write_or_die(data->fd, line, len);
1579 return 0;
1580}
1581
26a063a1
JH
1582static struct lock_file packlock;
1583
c0277d15
JH
1584static int repack_without_ref(const char *refname)
1585{
d66da478 1586 struct repack_without_ref_sb data;
d3177275 1587 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 1588 if (find_ref(packed, refname) == NULL)
c0277d15 1589 return 0;
d66da478
MH
1590 data.refname = refname;
1591 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1592 if (data.fd < 0) {
1b018fd9 1593 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1594 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1595 }
d3177275 1596 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1597 return commit_lock_file(&packlock);
1598}
1599
eca35a25 1600int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1601{
1602 struct ref_lock *lock;
eca35a25 1603 int err, i = 0, ret = 0, flag = 0;
c0277d15 1604
68db31cc 1605 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1606 if (!lock)
1607 return 1;
045a476f 1608 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1609 /* loose */
eca35a25
MV
1610 const char *path;
1611
1612 if (!(delopt & REF_NODEREF)) {
1613 i = strlen(lock->lk->filename) - 5; /* .lock */
1614 lock->lk->filename[i] = 0;
1615 path = lock->lk->filename;
1616 } else {
9db56f71 1617 path = git_path("%s", refname);
eca35a25 1618 }
691f1a28
AR
1619 err = unlink_or_warn(path);
1620 if (err && errno != ENOENT)
c0277d15 1621 ret = 1;
691f1a28 1622
eca35a25
MV
1623 if (!(delopt & REF_NODEREF))
1624 lock->lk->filename[i] = '.';
c0277d15
JH
1625 }
1626 /* removing the loose one could have resurrected an earlier
1627 * packed one. Also, if it was not loose we need to repack
1628 * without it.
1629 */
1630 ret |= repack_without_ref(refname);
1631
691f1a28 1632 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1633 invalidate_ref_cache(NULL);
c0277d15
JH
1634 unlock_ref(lock);
1635 return ret;
4bd18c43
SP
1636}
1637
765c2258
PH
1638/*
1639 * People using contrib's git-new-workdir have .git/logs/refs ->
1640 * /some/other/path/.git/logs/refs, and that may live on another device.
1641 *
1642 * IOW, to avoid cross device rename errors, the temporary renamed log must
1643 * live into logs/refs.
1644 */
1645#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1646
dfefa935 1647int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1648{
c976d415
LH
1649 unsigned char sha1[20], orig_sha1[20];
1650 int flag = 0, logmoved = 0;
1651 struct ref_lock *lock;
c976d415 1652 struct stat loginfo;
dfefa935 1653 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1654 const char *symref = NULL;
316b097a 1655 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1656
450d4c0f 1657 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1658 return error("reflog for %s is a symlink", oldrefname);
c976d415 1659
8d68493f 1660 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1661 if (flag & REF_ISSYMREF)
fa58186c 1662 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1663 oldrefname);
eca35a25 1664 if (!symref)
dfefa935 1665 return error("refname %s not found", oldrefname);
c976d415 1666
316b097a 1667 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1668 return 1;
1669
316b097a 1670 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1671 return 1;
1672
dfefa935 1673 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1674 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1675 oldrefname, strerror(errno));
c976d415 1676
dfefa935
MH
1677 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1678 error("unable to delete old %s", oldrefname);
c976d415
LH
1679 goto rollback;
1680 }
1681
dfefa935
MH
1682 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1683 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1684 if (errno==EISDIR) {
dfefa935
MH
1685 if (remove_empty_directories(git_path("%s", newrefname))) {
1686 error("Directory not empty: %s", newrefname);
c976d415
LH
1687 goto rollback;
1688 }
1689 } else {
dfefa935 1690 error("unable to delete existing %s", newrefname);
c976d415
LH
1691 goto rollback;
1692 }
1693 }
1694
dfefa935
MH
1695 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1696 error("unable to create directory for %s", newrefname);
c976d415
LH
1697 goto rollback;
1698 }
1699
1700 retry:
dfefa935 1701 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1702 if (errno==EISDIR || errno==ENOTDIR) {
1703 /*
1704 * rename(a, b) when b is an existing
1705 * directory ought to result in ISDIR, but
1706 * Solaris 5.8 gives ENOTDIR. Sheesh.
1707 */
dfefa935
MH
1708 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1709 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1710 goto rollback;
1711 }
1712 goto retry;
1713 } else {
765c2258 1714 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1715 newrefname, strerror(errno));
c976d415
LH
1716 goto rollback;
1717 }
1718 }
1719 logmoved = log;
1720
dfefa935 1721 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1722 if (!lock) {
dfefa935 1723 error("unable to lock %s for update", newrefname);
c976d415
LH
1724 goto rollback;
1725 }
c976d415
LH
1726 lock->force_write = 1;
1727 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1728 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1729 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1730 goto rollback;
1731 }
1732
1733 return 0;
1734
1735 rollback:
dfefa935 1736 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1737 if (!lock) {
dfefa935 1738 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1739 goto rollbacklog;
1740 }
1741
1742 lock->force_write = 1;
1743 flag = log_all_ref_updates;
1744 log_all_ref_updates = 0;
1745 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1746 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1747 log_all_ref_updates = flag;
1748
1749 rollbacklog:
dfefa935 1750 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1751 error("unable to restore logfile %s from %s: %s",
dfefa935 1752 oldrefname, newrefname, strerror(errno));
c976d415 1753 if (!logmoved && log &&
dfefa935 1754 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1755 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1756 oldrefname, strerror(errno));
c976d415
LH
1757
1758 return 1;
1759}
1760
435fc852 1761int close_ref(struct ref_lock *lock)
b531394d
BC
1762{
1763 if (close_lock_file(lock->lk))
1764 return -1;
1765 lock->lock_fd = -1;
1766 return 0;
1767}
1768
435fc852 1769int commit_ref(struct ref_lock *lock)
b531394d
BC
1770{
1771 if (commit_lock_file(lock->lk))
1772 return -1;
1773 lock->lock_fd = -1;
1774 return 0;
1775}
1776
e5f38ec3 1777void unlock_ref(struct ref_lock *lock)
4bd18c43 1778{
4ed7cd3a
BC
1779 /* Do not free lock->lk -- atexit() still looks at them */
1780 if (lock->lk)
1781 rollback_lock_file(lock->lk);
434cd0cd 1782 free(lock->ref_name);
1655707c 1783 free(lock->orig_ref_name);
4bd18c43
SP
1784 free(lock);
1785}
1786
0ec29a47
JH
1787/*
1788 * copy the reflog message msg to buf, which has been allocated sufficiently
1789 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1790 * because reflog file is one line per entry.
1791 */
1792static int copy_msg(char *buf, const char *msg)
1793{
1794 char *cp = buf;
1795 char c;
1796 int wasspace = 1;
1797
1798 *cp++ = '\t';
1799 while ((c = *msg++)) {
1800 if (wasspace && isspace(c))
1801 continue;
1802 wasspace = isspace(c);
1803 if (wasspace)
1804 c = ' ';
1805 *cp++ = c;
1806 }
1807 while (buf < cp && isspace(cp[-1]))
1808 cp--;
1809 *cp++ = '\n';
1810 return cp - buf;
1811}
1812
dfefa935 1813int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 1814{
859c3017 1815 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1816
dfefa935 1817 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 1818 if (log_all_ref_updates &&
dfefa935
MH
1819 (!prefixcmp(refname, "refs/heads/") ||
1820 !prefixcmp(refname, "refs/remotes/") ||
1821 !prefixcmp(refname, "refs/notes/") ||
1822 !strcmp(refname, "HEAD"))) {
157aaea5 1823 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1824 return error("unable to create directory for %s",
157aaea5 1825 logfile);
6de08ae6
SP
1826 oflags |= O_CREAT;
1827 }
1828
157aaea5 1829 logfd = open(logfile, oflags, 0666);
6de08ae6 1830 if (logfd < 0) {
1974bf62 1831 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1832 return 0;
3b463c3f
JH
1833
1834 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1835 if (remove_empty_directories(logfile)) {
3b463c3f 1836 return error("There are still logs under '%s'",
157aaea5 1837 logfile);
3b463c3f 1838 }
157aaea5 1839 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1840 }
1841
1842 if (logfd < 0)
1843 return error("Unable to append to %s: %s",
157aaea5 1844 logfile, strerror(errno));
6de08ae6
SP
1845 }
1846
157aaea5 1847 adjust_shared_perm(logfile);
859c3017
EM
1848 close(logfd);
1849 return 0;
1850}
443b92b6 1851
dfefa935 1852static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
1853 const unsigned char *new_sha1, const char *msg)
1854{
1855 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1856 unsigned maxlen, len;
1857 int msglen;
157aaea5 1858 char log_file[PATH_MAX];
859c3017
EM
1859 char *logrec;
1860 const char *committer;
1861
1862 if (log_all_ref_updates < 0)
1863 log_all_ref_updates = !is_bare_repository();
1864
dfefa935 1865 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
1866 if (result)
1867 return result;
1868
1869 logfd = open(log_file, oflags);
1870 if (logfd < 0)
1871 return 0;
0ec29a47 1872 msglen = msg ? strlen(msg) : 0;
774751a8 1873 committer = git_committer_info(0);
8ac65937
JH
1874 maxlen = strlen(committer) + msglen + 100;
1875 logrec = xmalloc(maxlen);
1876 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1877 sha1_to_hex(old_sha1),
1878 sha1_to_hex(new_sha1),
8ac65937
JH
1879 committer);
1880 if (msglen)
0ec29a47 1881 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1882 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1883 free(logrec);
91c8d590 1884 if (close(logfd) != 0 || written != len)
9a13f0b7 1885 return error("Unable to append to %s", log_file);
6de08ae6
SP
1886 return 0;
1887}
1888
c3b0dec5
LT
1889static int is_branch(const char *refname)
1890{
1891 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1892}
1893
4bd18c43
SP
1894int write_ref_sha1(struct ref_lock *lock,
1895 const unsigned char *sha1, const char *logmsg)
1896{
1897 static char term = '\n';
c3b0dec5 1898 struct object *o;
4bd18c43
SP
1899
1900 if (!lock)
95fc7512 1901 return -1;
a89fccd2 1902 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1903 unlock_ref(lock);
1904 return 0;
95fc7512 1905 }
c3b0dec5
LT
1906 o = parse_object(sha1);
1907 if (!o) {
7be8b3ba 1908 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
1909 lock->ref_name, sha1_to_hex(sha1));
1910 unlock_ref(lock);
1911 return -1;
1912 }
1913 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1914 error("Trying to write non-commit object %s to branch %s",
1915 sha1_to_hex(sha1), lock->ref_name);
1916 unlock_ref(lock);
1917 return -1;
1918 }
93822c22
AW
1919 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1920 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1921 || close_ref(lock) < 0) {
c33d5174 1922 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1923 unlock_ref(lock);
1924 return -1;
1925 }
8bf90dc9 1926 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
1927 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1928 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1929 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1930 unlock_ref(lock);
1931 return -1;
1932 }
605fac8b
NP
1933 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1934 /*
1935 * Special hack: If a branch is updated directly and HEAD
1936 * points to it (may happen on the remote side of a push
1937 * for example) then logically the HEAD reflog should be
1938 * updated too.
1939 * A generic solution implies reverse symref information,
1940 * but finding all symrefs pointing to the given branch
1941 * would be rather costly for this rare event (the direct
1942 * update of a branch) to be worth it. So let's cheat and
1943 * check with HEAD only which should cover 99% of all usage
1944 * scenarios (even 100% of the default ones).
1945 */
1946 unsigned char head_sha1[20];
1947 int head_flag;
1948 const char *head_ref;
8cad4744 1949 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
1950 if (head_ref && (head_flag & REF_ISSYMREF) &&
1951 !strcmp(head_ref, lock->ref_name))
1952 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1953 }
b531394d 1954 if (commit_ref(lock)) {
434cd0cd 1955 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1956 unlock_ref(lock);
1957 return -1;
1958 }
4bd18c43
SP
1959 unlock_ref(lock);
1960 return 0;
95fc7512 1961}
d556fae2 1962
8b5157e4
NP
1963int create_symref(const char *ref_target, const char *refs_heads_master,
1964 const char *logmsg)
41b625b0
NP
1965{
1966 const char *lockpath;
1967 char ref[1000];
1968 int fd, len, written;
a4f34cbb 1969 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1970 unsigned char old_sha1[20], new_sha1[20];
1971
1972 if (logmsg && read_ref(ref_target, old_sha1))
1973 hashclr(old_sha1);
41b625b0 1974
d48744d1
JH
1975 if (safe_create_leading_directories(git_HEAD) < 0)
1976 return error("unable to create directory for %s", git_HEAD);
1977
41b625b0
NP
1978#ifndef NO_SYMLINK_HEAD
1979 if (prefer_symlink_refs) {
1980 unlink(git_HEAD);
1981 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1982 goto done;
41b625b0
NP
1983 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1984 }
1985#endif
1986
1987 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1988 if (sizeof(ref) <= len) {
1989 error("refname too long: %s", refs_heads_master);
47fc52e2 1990 goto error_free_return;
41b625b0
NP
1991 }
1992 lockpath = mkpath("%s.lock", git_HEAD);
1993 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1994 if (fd < 0) {
1995 error("Unable to open %s for writing", lockpath);
47fc52e2 1996 goto error_free_return;
41b625b0
NP
1997 }
1998 written = write_in_full(fd, ref, len);
91c8d590 1999 if (close(fd) != 0 || written != len) {
41b625b0 2000 error("Unable to write to %s", lockpath);
47fc52e2 2001 goto error_unlink_return;
41b625b0
NP
2002 }
2003 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2004 error("Unable to create %s", git_HEAD);
47fc52e2 2005 goto error_unlink_return;
41b625b0
NP
2006 }
2007 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2008 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2009 error_unlink_return:
691f1a28 2010 unlink_or_warn(lockpath);
47fc52e2
JH
2011 error_free_return:
2012 free(git_HEAD);
2013 return -1;
41b625b0 2014 }
8b5157e4 2015
ee96d11b 2016#ifndef NO_SYMLINK_HEAD
8b5157e4 2017 done:
ee96d11b 2018#endif
8b5157e4
NP
2019 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2020 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2021
47fc52e2 2022 free(git_HEAD);
41b625b0
NP
2023 return 0;
2024}
2025
16d7cc90
JH
2026static char *ref_msg(const char *line, const char *endp)
2027{
2028 const char *ep;
16d7cc90 2029 line += 82;
182af834
PH
2030 ep = memchr(line, '\n', endp - line);
2031 if (!ep)
2032 ep = endp;
2033 return xmemdupz(line, ep - line);
16d7cc90
JH
2034}
2035
dfefa935
MH
2036int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2037 unsigned char *sha1, char **msg,
2038 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2039{
e5229042 2040 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2041 char *tz_c;
e29cb53a 2042 int logfd, tz, reccnt = 0;
d556fae2
SP
2043 struct stat st;
2044 unsigned long date;
e5229042 2045 unsigned char logged_sha1[20];
cb48cb58 2046 void *log_mapped;
dc49cd76 2047 size_t mapsz;
d556fae2 2048
dfefa935 2049 logfile = git_path("logs/%s", refname);
d556fae2
SP
2050 logfd = open(logfile, O_RDONLY, 0);
2051 if (logfd < 0)
d824cbba 2052 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2053 fstat(logfd, &st);
2054 if (!st.st_size)
2055 die("Log %s is empty.", logfile);
dc49cd76
SP
2056 mapsz = xsize_t(st.st_size);
2057 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2058 logdata = log_mapped;
d556fae2
SP
2059 close(logfd);
2060
e5229042 2061 lastrec = NULL;
d556fae2
SP
2062 rec = logend = logdata + st.st_size;
2063 while (logdata < rec) {
e29cb53a 2064 reccnt++;
d556fae2
SP
2065 if (logdata < rec && *(rec-1) == '\n')
2066 rec--;
e5229042
SP
2067 lastgt = NULL;
2068 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2069 rec--;
e5229042
SP
2070 if (*rec == '>')
2071 lastgt = rec;
2072 }
2073 if (!lastgt)
d556fae2 2074 die("Log %s is corrupt.", logfile);
e5229042 2075 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2076 if (date <= at_time || cnt == 0) {
76a44c5c 2077 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2078 if (msg)
2079 *msg = ref_msg(rec, logend);
2080 if (cutoff_time)
2081 *cutoff_time = date;
2082 if (cutoff_tz)
2083 *cutoff_tz = tz;
2084 if (cutoff_cnt)
76a44c5c 2085 *cutoff_cnt = reccnt - 1;
e5229042
SP
2086 if (lastrec) {
2087 if (get_sha1_hex(lastrec, logged_sha1))
2088 die("Log %s is corrupt.", logfile);
2089 if (get_sha1_hex(rec + 41, sha1))
2090 die("Log %s is corrupt.", logfile);
a89fccd2 2091 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2092 warning("Log %s has gap after %s.",
73013afd 2093 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2094 }
e5f38ec3
JH
2095 }
2096 else if (date == at_time) {
e5229042
SP
2097 if (get_sha1_hex(rec + 41, sha1))
2098 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2099 }
2100 else {
e5229042
SP
2101 if (get_sha1_hex(rec + 41, logged_sha1))
2102 die("Log %s is corrupt.", logfile);
a89fccd2 2103 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2104 warning("Log %s unexpectedly ended on %s.",
73013afd 2105 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2106 }
2107 }
dc49cd76 2108 munmap(log_mapped, mapsz);
d556fae2
SP
2109 return 0;
2110 }
e5229042 2111 lastrec = rec;
ab2a1a32
JH
2112 if (cnt > 0)
2113 cnt--;
d556fae2
SP
2114 }
2115
e5229042
SP
2116 rec = logdata;
2117 while (rec < logend && *rec != '>' && *rec != '\n')
2118 rec++;
2119 if (rec == logend || *rec == '\n')
d556fae2 2120 die("Log %s is corrupt.", logfile);
e5229042 2121 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2122 tz = strtoul(tz_c, NULL, 10);
2123 if (get_sha1_hex(logdata, sha1))
2124 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2125 if (is_null_sha1(sha1)) {
2126 if (get_sha1_hex(logdata + 41, sha1))
2127 die("Log %s is corrupt.", logfile);
2128 }
16d7cc90
JH
2129 if (msg)
2130 *msg = ref_msg(logdata, logend);
dc49cd76 2131 munmap(log_mapped, mapsz);
16d7cc90
JH
2132
2133 if (cutoff_time)
2134 *cutoff_time = date;
2135 if (cutoff_tz)
2136 *cutoff_tz = tz;
2137 if (cutoff_cnt)
2138 *cutoff_cnt = reccnt;
2139 return 1;
d556fae2 2140}
2ff81662 2141
dfefa935 2142int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
2143{
2144 const char *logfile;
2145 FILE *logfp;
8ca78803 2146 struct strbuf sb = STRBUF_INIT;
2266bf27 2147 int ret = 0;
2ff81662 2148
dfefa935 2149 logfile = git_path("logs/%s", refname);
2ff81662
JH
2150 logfp = fopen(logfile, "r");
2151 if (!logfp)
883d60fa 2152 return -1;
101d15e0
JH
2153
2154 if (ofs) {
2155 struct stat statbuf;
2156 if (fstat(fileno(logfp), &statbuf) ||
2157 statbuf.st_size < ofs ||
2158 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 2159 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 2160 fclose(logfp);
8ca78803 2161 strbuf_release(&sb);
101d15e0 2162 return -1;
9d33f7c2 2163 }
101d15e0
JH
2164 }
2165
8ca78803 2166 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 2167 unsigned char osha1[20], nsha1[20];
883d60fa
JS
2168 char *email_end, *message;
2169 unsigned long timestamp;
8ca78803 2170 int tz;
2ff81662
JH
2171
2172 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
2173 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2174 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2175 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2176 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
2177 email_end[1] != ' ' ||
2178 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2179 !message || message[0] != ' ' ||
2180 (message[1] != '+' && message[1] != '-') ||
2181 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2182 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2183 continue; /* corrupt? */
883d60fa
JS
2184 email_end[1] = '\0';
2185 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2186 if (message[6] != '\t')
2187 message += 6;
2188 else
2189 message += 7;
8ca78803
RS
2190 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2191 cb_data);
883d60fa 2192 if (ret)
2266bf27 2193 break;
2ff81662
JH
2194 }
2195 fclose(logfp);
8ca78803 2196 strbuf_release(&sb);
2266bf27 2197 return ret;
2ff81662 2198}
e29cb53a 2199
dfefa935 2200int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2201{
dfefa935 2202 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2203}
2204
eb8381c8
NP
2205static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
2206{
d3177275 2207 DIR *d = opendir(git_path("logs/%s", base));
fcee5a14 2208 int retval = 0;
eb8381c8 2209
d3177275 2210 if (d) {
eb8381c8
NP
2211 struct dirent *de;
2212 int baselen = strlen(base);
2213 char *log = xmalloc(baselen + 257);
2214
2215 memcpy(log, base, baselen);
2216 if (baselen && base[baselen-1] != '/')
2217 log[baselen++] = '/';
2218
d3177275 2219 while ((de = readdir(d)) != NULL) {
eb8381c8
NP
2220 struct stat st;
2221 int namelen;
2222
2223 if (de->d_name[0] == '.')
2224 continue;
2225 namelen = strlen(de->d_name);
2226 if (namelen > 255)
2227 continue;
2228 if (has_extension(de->d_name, ".lock"))
2229 continue;
2230 memcpy(log + baselen, de->d_name, namelen+1);
2231 if (stat(git_path("logs/%s", log), &st) < 0)
2232 continue;
2233 if (S_ISDIR(st.st_mode)) {
2234 retval = do_for_each_reflog(log, fn, cb_data);
2235 } else {
2236 unsigned char sha1[20];
c6893323 2237 if (read_ref_full(log, sha1, 0, NULL))
eb8381c8
NP
2238 retval = error("bad ref for %s", log);
2239 else
2240 retval = fn(log, sha1, 0, cb_data);
2241 }
2242 if (retval)
2243 break;
2244 }
2245 free(log);
d3177275 2246 closedir(d);
eb8381c8 2247 }
acb39f64 2248 else if (*base)
fcee5a14 2249 return errno;
eb8381c8
NP
2250 return retval;
2251}
2252
2253int for_each_reflog(each_ref_fn fn, void *cb_data)
2254{
2255 return do_for_each_reflog("", fn, cb_data);
2256}
3d9f037c
CR
2257
2258int update_ref(const char *action, const char *refname,
2259 const unsigned char *sha1, const unsigned char *oldval,
2260 int flags, enum action_on_err onerr)
2261{
2262 static struct ref_lock *lock;
2263 lock = lock_any_ref_for_update(refname, oldval, flags);
2264 if (!lock) {
2265 const char *str = "Cannot lock the ref '%s'.";
2266 switch (onerr) {
2267 case MSG_ON_ERR: error(str, refname); break;
2268 case DIE_ON_ERR: die(str, refname); break;
2269 case QUIET_ON_ERR: break;
2270 }
2271 return 1;
2272 }
2273 if (write_ref_sha1(lock, sha1, action) < 0) {
2274 const char *str = "Cannot update the ref '%s'.";
2275 switch (onerr) {
2276 case MSG_ON_ERR: error(str, refname); break;
2277 case DIE_ON_ERR: die(str, refname); break;
2278 case QUIET_ON_ERR: break;
2279 }
2280 return 1;
2281 }
2282 return 0;
2283}
cda69f48 2284
5483f799 2285struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2286{
2287 for ( ; list; list = list->next)
2288 if (!strcmp(list->name, name))
5483f799 2289 return (struct ref *)list;
cda69f48
JK
2290 return NULL;
2291}
7c2b3029
JK
2292
2293/*
2294 * generate a format suitable for scanf from a ref_rev_parse_rules
2295 * rule, that is replace the "%.*s" spec with a "%s" spec
2296 */
2297static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2298{
2299 char *spec;
2300
2301 spec = strstr(rule, "%.*s");
2302 if (!spec || strstr(spec + 4, "%.*s"))
2303 die("invalid rule in ref_rev_parse_rules: %s", rule);
2304
2305 /* copy all until spec */
2306 strncpy(scanf_fmt, rule, spec - rule);
2307 scanf_fmt[spec - rule] = '\0';
2308 /* copy new spec */
2309 strcat(scanf_fmt, "%s");
2310 /* copy remaining rule */
2311 strcat(scanf_fmt, spec + 4);
2312
2313 return;
2314}
2315
dfefa935 2316char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2317{
2318 int i;
2319 static char **scanf_fmts;
2320 static int nr_rules;
2321 char *short_name;
2322
2323 /* pre generate scanf formats from ref_rev_parse_rules[] */
2324 if (!nr_rules) {
2325 size_t total_len = 0;
2326
2327 /* the rule list is NULL terminated, count them first */
2328 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2329 /* no +1 because strlen("%s") < strlen("%.*s") */
2330 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2331
2332 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2333
2334 total_len = 0;
2335 for (i = 0; i < nr_rules; i++) {
2336 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2337 + total_len;
2338 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2339 total_len += strlen(ref_rev_parse_rules[i]);
2340 }
2341 }
2342
2343 /* bail out if there are no rules */
2344 if (!nr_rules)
dfefa935 2345 return xstrdup(refname);
7c2b3029 2346
dfefa935
MH
2347 /* buffer for scanf result, at most refname must fit */
2348 short_name = xstrdup(refname);
7c2b3029
JK
2349
2350 /* skip first rule, it will always match */
2351 for (i = nr_rules - 1; i > 0 ; --i) {
2352 int j;
6e7b3309 2353 int rules_to_fail = i;
7c2b3029
JK
2354 int short_name_len;
2355
dfefa935 2356 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2357 continue;
2358
2359 short_name_len = strlen(short_name);
2360
6e7b3309
BW
2361 /*
2362 * in strict mode, all (except the matched one) rules
2363 * must fail to resolve to a valid non-ambiguous ref
2364 */
2365 if (strict)
2366 rules_to_fail = nr_rules;
2367
7c2b3029
JK
2368 /*
2369 * check if the short name resolves to a valid ref,
2370 * but use only rules prior to the matched one
2371 */
6e7b3309 2372 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2373 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2374 char refname[PATH_MAX];
2375
6e7b3309
BW
2376 /* skip matched rule */
2377 if (i == j)
2378 continue;
2379
7c2b3029
JK
2380 /*
2381 * the short name is ambiguous, if it resolves
2382 * (with this previous rule) to a valid ref
2383 * read_ref() returns 0 on success
2384 */
2385 mksnpath(refname, sizeof(refname),
2386 rule, short_name_len, short_name);
c6893323 2387 if (ref_exists(refname))
7c2b3029
JK
2388 break;
2389 }
2390
2391 /*
2392 * short name is non-ambiguous if all previous rules
2393 * haven't resolved to a valid ref
2394 */
6e7b3309 2395 if (j == rules_to_fail)
7c2b3029
JK
2396 return short_name;
2397 }
2398
2399 free(short_name);
dfefa935 2400 return xstrdup(refname);
7c2b3029 2401}