read_loose_refs(): eliminate ref_cache argument
[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
f006c42a
MH
109struct ref_cache;
110
d3177275 111struct ref_dir {
e9c4c111 112 int nr, alloc;
e6ed3ca6
MH
113
114 /*
115 * Entries with index 0 <= i < sorted are sorted by name. New
116 * entries are appended to the list unsorted, and are sorted
117 * only when required; thus we avoid the need to sort the list
118 * after the addition of every reference.
119 */
120 int sorted;
121
f006c42a
MH
122 /* A pointer to the ref_cache that contains this ref_dir. */
123 struct ref_cache *ref_cache;
124
d3177275 125 struct ref_entry **entries;
e9c4c111
JP
126};
127
432ad41e
MH
128/* ISSYMREF=0x01, ISPACKED=0x02, and ISBROKEN=0x04 are public interfaces */
129#define REF_KNOWS_PEELED 0x08
130#define REF_DIR 0x10
cf0adba7 131
432ad41e
MH
132/*
133 * A ref_entry represents either a reference or a "subdirectory" of
134 * references. Each directory in the reference namespace is
135 * represented by a ref_entry with (flags & REF_DIR) set and
136 * containing a subdir member that holds the entries in that
137 * directory. References are represented by a ref_entry with (flags &
138 * REF_DIR) unset and a value member that describes the reference's
139 * value. The flag member is at the ref_entry level, but it is also
140 * needed to interpret the contents of the value field (in other
141 * words, a ref_value object is not very much use without the
142 * enclosing ref_entry).
143 *
144 * Reference names cannot end with slash and directories' names are
145 * always stored with a trailing slash (except for the top-level
146 * directory, which is always denoted by ""). This has two nice
147 * consequences: (1) when the entries in each subdir are sorted
148 * lexicographically by name (as they usually are), the references in
149 * a whole tree can be generated in lexicographic order by traversing
150 * the tree in left-to-right, depth-first order; (2) the names of
151 * references and subdirectories cannot conflict, and therefore the
152 * presence of an empty subdirectory does not block the creation of a
153 * similarly-named reference. (The fact that reference names with the
154 * same leading components can conflict *with each other* is a
155 * separate issue that is regulated by is_refname_available().)
156 *
157 * Please note that the name field contains the fully-qualified
158 * reference (or subdirectory) name. Space could be saved by only
159 * storing the relative names. But that would require the full names
160 * to be generated on the fly when iterating in do_for_each_ref(), and
161 * would break callback functions, who have always been able to assume
162 * that the name strings that they are passed will not be freed during
163 * the iteration.
164 */
bc5fd6d3
MH
165struct ref_entry {
166 unsigned char flag; /* ISSYMREF? ISPACKED? */
593f1bb8 167 union {
432ad41e
MH
168 struct ref_value value; /* if not (flags&REF_DIR) */
169 struct ref_dir subdir; /* if (flags&REF_DIR) */
593f1bb8 170 } u;
432ad41e
MH
171 /*
172 * The full name of the reference (e.g., "refs/heads/master")
173 * or the full name of the directory with a trailing slash
174 * (e.g., "refs/heads/"):
175 */
bc5fd6d3
MH
176 char name[FLEX_ARRAY];
177};
e1e22e37 178
d7826d54
MH
179static struct ref_dir *get_ref_dir(struct ref_entry *entry)
180{
181 assert(entry->flag & REF_DIR);
182 return &entry->u.subdir;
183}
184
cddc4258
MH
185static struct ref_entry *create_ref_entry(const char *refname,
186 const unsigned char *sha1, int flag,
187 int check_name)
e1e22e37
LT
188{
189 int len;
cddc4258 190 struct ref_entry *ref;
e1e22e37 191
09116a1c 192 if (check_name &&
dfefa935
MH
193 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
194 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
195 len = strlen(refname) + 1;
196 ref = xmalloc(sizeof(struct ref_entry) + len);
593f1bb8
MH
197 hashcpy(ref->u.value.sha1, sha1);
198 hashclr(ref->u.value.peeled);
cddc4258
MH
199 memcpy(ref->name, refname, len);
200 ref->flag = flag;
201 return ref;
202}
203
432ad41e
MH
204static void clear_ref_dir(struct ref_dir *dir);
205
732134ed
MH
206static void free_ref_entry(struct ref_entry *entry)
207{
432ad41e 208 if (entry->flag & REF_DIR)
d7826d54 209 clear_ref_dir(get_ref_dir(entry));
732134ed
MH
210 free(entry);
211}
212
432ad41e
MH
213/*
214 * Add a ref_entry to the end of dir (unsorted). Entry is always
215 * stored directly in dir; no recursion into subdirectories is
216 * done.
217 */
218static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
cddc4258 219{
432ad41e
MH
220 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
221 dir->entries[dir->nr++] = entry;
c774aab9
JP
222}
223
432ad41e
MH
224/*
225 * Clear and free all entries in dir, recursively.
226 */
d3177275 227static void clear_ref_dir(struct ref_dir *dir)
bc5fd6d3
MH
228{
229 int i;
d3177275
MH
230 for (i = 0; i < dir->nr; i++)
231 free_ref_entry(dir->entries[i]);
232 free(dir->entries);
233 dir->sorted = dir->nr = dir->alloc = 0;
234 dir->entries = NULL;
bc5fd6d3
MH
235}
236
432ad41e
MH
237/*
238 * Create a struct ref_entry object for the specified dirname.
239 * dirname is the name of the directory with a trailing slash (e.g.,
240 * "refs/heads/") or "" for the top-level directory.
241 */
f006c42a
MH
242static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
243 const char *dirname)
432ad41e
MH
244{
245 struct ref_entry *direntry;
246 int len = strlen(dirname);
247 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
248 memcpy(direntry->name, dirname, len + 1);
f006c42a 249 direntry->u.subdir.ref_cache = ref_cache;
432ad41e
MH
250 direntry->flag = REF_DIR;
251 return direntry;
252}
253
e9c4c111 254static int ref_entry_cmp(const void *a, const void *b)
c774aab9 255{
e9c4c111
JP
256 struct ref_entry *one = *(struct ref_entry **)a;
257 struct ref_entry *two = *(struct ref_entry **)b;
258 return strcmp(one->name, two->name);
259}
c774aab9 260
d3177275 261static void sort_ref_dir(struct ref_dir *dir);
bc5fd6d3 262
432ad41e
MH
263/*
264 * Return the entry with the given refname from the ref_dir
265 * (non-recursively), sorting dir if necessary. Return NULL if no
266 * such entry is found.
267 */
d3177275 268static struct ref_entry *search_ref_dir(struct ref_dir *dir, const char *refname)
bc5fd6d3
MH
269{
270 struct ref_entry *e, **r;
271 int len;
272
432ad41e 273 if (refname == NULL || !dir->nr)
bc5fd6d3
MH
274 return NULL;
275
d3177275 276 sort_ref_dir(dir);
432ad41e 277
bc5fd6d3
MH
278 len = strlen(refname) + 1;
279 e = xmalloc(sizeof(struct ref_entry) + len);
280 memcpy(e->name, refname, len);
281
d3177275 282 r = bsearch(&e, dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
bc5fd6d3
MH
283
284 free(e);
285
286 if (r == NULL)
287 return NULL;
288
289 return *r;
290}
291
f348ac92
MH
292/*
293 * Search for a directory entry directly within dir (without
294 * recursing). Sort dir if necessary. subdirname must be a directory
295 * name (i.e., end in '/'). If mkdir is set, then create the
296 * directory if it is missing; otherwise, return NULL if the desired
297 * directory cannot be found.
298 */
3f3aa1bc
MH
299static struct ref_dir *search_for_subdir(struct ref_dir *dir,
300 const char *subdirname, int mkdir)
f348ac92
MH
301{
302 struct ref_entry *entry = search_ref_dir(dir, subdirname);
303 if (!entry) {
304 if (!mkdir)
305 return NULL;
f006c42a 306 entry = create_dir_entry(dir->ref_cache, subdirname);
f348ac92
MH
307 add_entry_to_dir(dir, entry);
308 }
3f3aa1bc 309 return get_ref_dir(entry);
f348ac92
MH
310}
311
432ad41e
MH
312/*
313 * If refname is a reference name, find the ref_dir within the dir
314 * tree that should hold refname. If refname is a directory name
315 * (i.e., ends in '/'), then return that ref_dir itself. dir must
316 * represent the top-level directory. Sort ref_dirs and recurse into
317 * subdirectories as necessary. If mkdir is set, then create any
318 * missing directories; otherwise, return NULL if the desired
319 * directory cannot be found.
320 */
321static struct ref_dir *find_containing_dir(struct ref_dir *dir,
322 const char *refname, int mkdir)
323{
5fa04418
MH
324 struct strbuf dirname;
325 const char *slash;
326 strbuf_init(&dirname, PATH_MAX);
327 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
3f3aa1bc 328 struct ref_dir *subdir;
5fa04418
MH
329 strbuf_add(&dirname,
330 refname + dirname.len,
331 (slash + 1) - (refname + dirname.len));
3f3aa1bc
MH
332 subdir = search_for_subdir(dir, dirname.buf, mkdir);
333 if (!subdir)
f348ac92 334 break;
3f3aa1bc 335 dir = subdir;
432ad41e
MH
336 }
337
5fa04418 338 strbuf_release(&dirname);
432ad41e
MH
339 return dir;
340}
341
342/*
343 * Find the value entry with the given name in dir, sorting ref_dirs
344 * and recursing into subdirectories as necessary. If the name is not
345 * found or it corresponds to a directory entry, return NULL.
346 */
347static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
348{
349 struct ref_entry *entry;
350 dir = find_containing_dir(dir, refname, 0);
351 if (!dir)
352 return NULL;
353 entry = search_ref_dir(dir, refname);
354 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
355}
356
357/*
358 * Add a ref_entry to the ref_dir (unsorted), recursing into
359 * subdirectories as necessary. dir must represent the top-level
360 * directory. Return 0 on success.
361 */
362static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
363{
364 dir = find_containing_dir(dir, ref->name, 1);
365 if (!dir)
366 return -1;
367 add_entry_to_dir(dir, ref);
368 return 0;
369}
370
202a56a9
MH
371/*
372 * Emit a warning and return true iff ref1 and ref2 have the same name
373 * and the same sha1. Die if they have the same name but different
374 * sha1s.
375 */
376static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
377{
432ad41e 378 if (strcmp(ref1->name, ref2->name))
202a56a9 379 return 0;
432ad41e
MH
380
381 /* Duplicate name; make sure that they don't conflict: */
382
383 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
384 /* This is impossible by construction */
385 die("Reference directory conflict: %s", ref1->name);
386
387 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
388 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
389
390 warning("Duplicated ref: %s", ref1->name);
391 return 1;
202a56a9
MH
392}
393
e6ed3ca6 394/*
432ad41e
MH
395 * Sort the entries in dir non-recursively (if they are not already
396 * sorted) and remove any duplicate entries.
e6ed3ca6 397 */
d3177275 398static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 399{
202a56a9 400 int i, j;
81a79d8e 401 struct ref_entry *last = NULL;
c774aab9 402
e6ed3ca6
MH
403 /*
404 * This check also prevents passing a zero-length array to qsort(),
405 * which is a problem on some platforms.
406 */
d3177275 407 if (dir->sorted == dir->nr)
e9c4c111 408 return;
c774aab9 409
d3177275 410 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 411
81a79d8e
MH
412 /* Remove any duplicates: */
413 for (i = 0, j = 0; j < dir->nr; j++) {
414 struct ref_entry *entry = dir->entries[j];
415 if (last && is_dup_ref(last, entry))
416 free_ref_entry(entry);
417 else
418 last = dir->entries[i++] = entry;
e9c4c111 419 }
81a79d8e 420 dir->sorted = dir->nr = i;
e9c4c111 421}
c774aab9 422
bc5fd6d3 423#define DO_FOR_EACH_INCLUDE_BROKEN 01
c774aab9 424
bc5fd6d3 425static struct ref_entry *current_ref;
c774aab9 426
bc5fd6d3
MH
427static int do_one_ref(const char *base, each_ref_fn fn, int trim,
428 int flags, void *cb_data, struct ref_entry *entry)
429{
429213e4 430 int retval;
bc5fd6d3
MH
431 if (prefixcmp(entry->name, base))
432 return 0;
c774aab9 433
bc5fd6d3
MH
434 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
435 if (entry->flag & REF_ISBROKEN)
436 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 437 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
438 error("%s does not point to a valid object!", entry->name);
439 return 0;
440 }
441 }
442 current_ref = entry;
593f1bb8 443 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
444 current_ref = NULL;
445 return retval;
bc5fd6d3 446}
c774aab9 447
c36b5bc2 448/*
d3177275 449 * Call fn for each reference in dir that has index in the range
432ad41e
MH
450 * offset <= index < dir->nr. Recurse into subdirectories that are in
451 * that index range, sorting them before iterating. This function
452 * does not sort dir itself; it should be sorted beforehand.
c36b5bc2 453 */
d3177275
MH
454static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
455 const char *base,
456 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
457{
458 int i;
d3177275
MH
459 assert(dir->sorted == dir->nr);
460 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
461 struct ref_entry *entry = dir->entries[i];
462 int retval;
463 if (entry->flag & REF_DIR) {
d7826d54
MH
464 struct ref_dir *subdir = get_ref_dir(entry);
465 sort_ref_dir(subdir);
466 retval = do_for_each_ref_in_dir(subdir, 0,
432ad41e
MH
467 base, fn, trim, flags, cb_data);
468 } else {
469 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
470 }
c36b5bc2
MH
471 if (retval)
472 return retval;
473 }
474 return 0;
475}
476
b3fd060f 477/*
d3177275 478 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
479 * by refname. Recurse into subdirectories. If a value entry appears
480 * in both dir1 and dir2, then only process the version that is in
481 * dir2. The input dirs must already be sorted, but subdirs will be
482 * sorted as needed.
b3fd060f 483 */
d3177275
MH
484static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
485 struct ref_dir *dir2,
486 const char *base, each_ref_fn fn, int trim,
487 int flags, void *cb_data)
b3fd060f
MH
488{
489 int retval;
490 int i1 = 0, i2 = 0;
491
d3177275
MH
492 assert(dir1->sorted == dir1->nr);
493 assert(dir2->sorted == dir2->nr);
432ad41e
MH
494 while (1) {
495 struct ref_entry *e1, *e2;
496 int cmp;
497 if (i1 == dir1->nr) {
498 return do_for_each_ref_in_dir(dir2, i2,
499 base, fn, trim, flags, cb_data);
500 }
501 if (i2 == dir2->nr) {
502 return do_for_each_ref_in_dir(dir1, i1,
503 base, fn, trim, flags, cb_data);
504 }
505 e1 = dir1->entries[i1];
506 e2 = dir2->entries[i2];
507 cmp = strcmp(e1->name, e2->name);
508 if (cmp == 0) {
509 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
510 /* Both are directories; descend them in parallel. */
d7826d54
MH
511 struct ref_dir *subdir1 = get_ref_dir(e1);
512 struct ref_dir *subdir2 = get_ref_dir(e2);
513 sort_ref_dir(subdir1);
514 sort_ref_dir(subdir2);
432ad41e 515 retval = do_for_each_ref_in_dirs(
d7826d54 516 subdir1, subdir2,
432ad41e
MH
517 base, fn, trim, flags, cb_data);
518 i1++;
519 i2++;
520 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
521 /* Both are references; ignore the one from dir1. */
522 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
523 i1++;
524 i2++;
525 } else {
526 die("conflict between reference and directory: %s",
527 e1->name);
528 }
b3fd060f 529 } else {
432ad41e
MH
530 struct ref_entry *e;
531 if (cmp < 0) {
532 e = e1;
b3fd060f 533 i1++;
432ad41e
MH
534 } else {
535 e = e2;
536 i2++;
537 }
538 if (e->flag & REF_DIR) {
d7826d54
MH
539 struct ref_dir *subdir = get_ref_dir(e);
540 sort_ref_dir(subdir);
432ad41e 541 retval = do_for_each_ref_in_dir(
d7826d54 542 subdir, 0,
432ad41e
MH
543 base, fn, trim, flags, cb_data);
544 } else {
545 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
b3fd060f
MH
546 }
547 }
548 if (retval)
549 return retval;
550 }
d3177275
MH
551 if (i1 < dir1->nr)
552 return do_for_each_ref_in_dir(dir1, i1,
553 base, fn, trim, flags, cb_data);
554 if (i2 < dir2->nr)
555 return do_for_each_ref_in_dir(dir2, i2,
556 base, fn, trim, flags, cb_data);
b3fd060f
MH
557 return 0;
558}
559
d66da478
MH
560/*
561 * Return true iff refname1 and refname2 conflict with each other.
562 * Two reference names conflict if one of them exactly matches the
563 * leading components of the other; e.g., "foo/bar" conflicts with
564 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
565 * "foo/barbados".
566 */
567static int names_conflict(const char *refname1, const char *refname2)
568{
5a4d4947
MH
569 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
570 ;
571 return (*refname1 == '\0' && *refname2 == '/')
572 || (*refname1 == '/' && *refname2 == '\0');
573}
574
575struct name_conflict_cb {
576 const char *refname;
577 const char *oldrefname;
578 const char *conflicting_refname;
579};
580
581static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
582 int flags, void *cb_data)
583{
584 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
585 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
586 return 0;
587 if (names_conflict(data->refname, existingrefname)) {
588 data->conflicting_refname = existingrefname;
589 return 1;
d66da478 590 }
5a4d4947 591 return 0;
d66da478
MH
592}
593
bc5fd6d3
MH
594/*
595 * Return true iff a reference named refname could be created without
5a4d4947
MH
596 * conflicting with the name of an existing reference in array. If
597 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
598 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
599 * operation).
600 */
601static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 602 struct ref_dir *dir)
bc5fd6d3 603{
5a4d4947
MH
604 struct name_conflict_cb data;
605 data.refname = refname;
606 data.oldrefname = oldrefname;
607 data.conflicting_refname = NULL;
608
d3177275
MH
609 sort_ref_dir(dir);
610 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
611 0, DO_FOR_EACH_INCLUDE_BROKEN,
612 &data)) {
5a4d4947
MH
613 error("'%s' exists; cannot create '%s'",
614 data.conflicting_refname, refname);
615 return 0;
bc5fd6d3
MH
616 }
617 return 1;
e1e22e37
LT
618}
619
5e290ff7
JH
620/*
621 * Future: need to be in "struct repository"
622 * when doing a full libification.
623 */
79c7ca54
MH
624static struct ref_cache {
625 struct ref_cache *next;
d12229f5
MH
626 struct ref_entry *loose;
627 struct ref_entry *packed;
ce40979c
MH
628 /* The submodule name, or "" for the main repo. */
629 char name[FLEX_ARRAY];
79c7ca54 630} *ref_cache;
0e88c130 631
760c4512 632static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 633{
d12229f5
MH
634 if (refs->packed) {
635 free_ref_entry(refs->packed);
636 refs->packed = NULL;
637 }
5e290ff7 638}
e1e22e37 639
760c4512
MH
640static void clear_loose_ref_cache(struct ref_cache *refs)
641{
d12229f5
MH
642 if (refs->loose) {
643 free_ref_entry(refs->loose);
644 refs->loose = NULL;
645 }
760c4512
MH
646}
647
79c7ca54 648static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 649{
ce40979c 650 int len;
79c7ca54 651 struct ref_cache *refs;
ce40979c
MH
652 if (!submodule)
653 submodule = "";
654 len = strlen(submodule) + 1;
79c7ca54 655 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 656 memcpy(refs->name, submodule, len);
e5dbf605
MH
657 return refs;
658}
659
4349a668 660/*
79c7ca54 661 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
662 * the main repository, use submodule==NULL. The returned structure
663 * will be allocated and initialized but not necessarily populated; it
664 * should not be freed.
665 */
79c7ca54 666static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 667{
79c7ca54 668 struct ref_cache *refs = ref_cache;
0e88c130
MH
669 if (!submodule)
670 submodule = "";
671 while (refs) {
672 if (!strcmp(submodule, refs->name))
673 return refs;
674 refs = refs->next;
4349a668 675 }
0e88c130 676
79c7ca54
MH
677 refs = create_ref_cache(submodule);
678 refs->next = ref_cache;
679 ref_cache = refs;
0e88c130 680 return refs;
4349a668
MH
681}
682
8be8bde7 683void invalidate_ref_cache(const char *submodule)
f130b116 684{
c5f29abd
MH
685 struct ref_cache *refs = get_ref_cache(submodule);
686 clear_packed_ref_cache(refs);
687 clear_loose_ref_cache(refs);
5e290ff7 688}
e1e22e37 689
bc5fd6d3
MH
690/*
691 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
692 * Return a pointer to the refname within the line (null-terminated),
693 * or NULL if there was a problem.
694 */
695static const char *parse_ref_line(char *line, unsigned char *sha1)
696{
697 /*
698 * 42: the answer to everything.
699 *
700 * In this case, it happens to be the answer to
701 * 40 (length of sha1 hex representation)
702 * +1 (space in between hex and name)
703 * +1 (newline at the end of the line)
704 */
705 int len = strlen(line) - 42;
706
707 if (len <= 0)
708 return NULL;
709 if (get_sha1_hex(line, sha1) < 0)
710 return NULL;
711 if (!isspace(line[40]))
712 return NULL;
713 line += 41;
714 if (isspace(*line))
715 return NULL;
716 if (line[len] != '\n')
717 return NULL;
718 line[len] = 0;
719
720 return line;
721}
722
d3177275 723static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 724{
e9c4c111 725 struct ref_entry *last = NULL;
f4204ab9
JH
726 char refline[PATH_MAX];
727 int flag = REF_ISPACKED;
728
729 while (fgets(refline, sizeof(refline), f)) {
730 unsigned char sha1[20];
dfefa935 731 const char *refname;
f4204ab9
JH
732 static const char header[] = "# pack-refs with:";
733
734 if (!strncmp(refline, header, sizeof(header)-1)) {
735 const char *traits = refline + sizeof(header) - 1;
736 if (strstr(traits, " peeled "))
737 flag |= REF_KNOWS_PEELED;
738 /* perhaps other traits later as well */
739 continue;
740 }
741
dfefa935
MH
742 refname = parse_ref_line(refline, sha1);
743 if (refname) {
dd73ecd1 744 last = create_ref_entry(refname, sha1, flag, 1);
d3177275 745 add_ref(dir, last);
f4204ab9
JH
746 continue;
747 }
748 if (last &&
749 refline[0] == '^' &&
750 strlen(refline) == 42 &&
751 refline[41] == '\n' &&
752 !get_sha1_hex(refline + 1, sha1))
593f1bb8 753 hashcpy(last->u.value.peeled, sha1);
f4204ab9 754 }
f4204ab9
JH
755}
756
d3177275 757static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 758{
d12229f5 759 if (!refs->packed) {
4349a668
MH
760 const char *packed_refs_file;
761 FILE *f;
0bad611b 762
f006c42a 763 refs->packed = create_dir_entry(refs, "");
316b097a
MH
764 if (*refs->name)
765 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
766 else
767 packed_refs_file = git_path("packed-refs");
768 f = fopen(packed_refs_file, "r");
e1e22e37 769 if (f) {
d7826d54 770 read_packed_refs(f, get_ref_dir(refs->packed));
e1e22e37 771 fclose(f);
e1e22e37 772 }
e1e22e37 773 }
d7826d54 774 return get_ref_dir(refs->packed);
e1e22e37
LT
775}
776
30249ee6
MH
777void add_packed_ref(const char *refname, const unsigned char *sha1)
778{
779 add_ref(get_packed_refs(get_ref_cache(NULL)),
780 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
781}
782
abc39098
MH
783/*
784 * Read the loose references for refs from the namespace dirname.
9f2fb4a3
MH
785 * dirname must end with '/'. dir must be the directory entry
786 * corresponding to dirname.
abc39098 787 */
423a1afc 788static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 789{
423a1afc 790 struct ref_cache *refs = dir->ref_cache;
d3177275 791 DIR *d;
0bad611b 792 const char *path;
d5fdae67 793 struct dirent *de;
abc39098 794 int dirnamelen = strlen(dirname);
72b64b44 795 struct strbuf refname;
0bad611b 796
3b124823 797 if (*refs->name)
66a3d20b 798 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 799 else
66a3d20b 800 path = git_path("%s", dirname);
0bad611b 801
d3177275 802 d = opendir(path);
d5fdae67
MH
803 if (!d)
804 return;
805
66a3d20b
MH
806 strbuf_init(&refname, dirnamelen + 257);
807 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
808
809 while ((de = readdir(d)) != NULL) {
810 unsigned char sha1[20];
811 struct stat st;
812 int flag;
d5fdae67
MH
813 const char *refdir;
814
815 if (de->d_name[0] == '.')
816 continue;
d5fdae67
MH
817 if (has_extension(de->d_name, ".lock"))
818 continue;
72b64b44 819 strbuf_addstr(&refname, de->d_name);
d5fdae67 820 refdir = *refs->name
72b64b44
MH
821 ? git_path_submodule(refs->name, "%s", refname.buf)
822 : git_path("%s", refname.buf);
823 if (stat(refdir, &st) < 0) {
824 ; /* silently ignore */
825 } else if (S_ISDIR(st.st_mode)) {
abc39098 826 strbuf_addch(&refname, '/');
423a1afc 827 read_loose_refs(refname.buf,
3f3aa1bc 828 search_for_subdir(dir, refname.buf, 1));
72b64b44
MH
829 } else {
830 if (*refs->name) {
831 hashclr(sha1);
832 flag = 0;
833 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
834 hashclr(sha1);
835 flag |= REF_ISBROKEN;
836 }
837 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
838 hashclr(sha1);
839 flag |= REF_ISBROKEN;
840 }
9f2fb4a3
MH
841 add_entry_to_dir(dir,
842 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 843 }
66a3d20b 844 strbuf_setlen(&refname, dirnamelen);
e1e22e37 845 }
72b64b44 846 strbuf_release(&refname);
d5fdae67 847 closedir(d);
e1e22e37
LT
848}
849
d3177275 850static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 851{
d12229f5 852 if (!refs->loose) {
f006c42a 853 refs->loose = create_dir_entry(refs, "");
423a1afc 854 read_loose_refs("refs/",
3f3aa1bc
MH
855 search_for_subdir(get_ref_dir(refs->loose),
856 "refs/", 1));
e1e22e37 857 }
d7826d54 858 return get_ref_dir(refs->loose);
e1e22e37
LT
859}
860
ca8db142
LT
861/* We allow "recursive" symbolic refs. Only within reason, though */
862#define MAXDEPTH 5
0ebde32c
LT
863#define MAXREFLEN (1024)
864
e5fa45c1
JH
865/*
866 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
867 * from the loose refs in ref_cache refs. Find <refname> in the
868 * packed-refs file for the submodule.
e5fa45c1 869 */
b0626608 870static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 871 const char *refname, unsigned char *sha1)
0ebde32c 872{
2c5c66be 873 struct ref_entry *ref;
d3177275 874 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 875
432ad41e 876 ref = find_ref(dir, refname);
b0626608
MH
877 if (ref == NULL)
878 return -1;
879
593f1bb8 880 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 881 return 0;
0ebde32c
LT
882}
883
b0626608 884static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 885 const char *refname, unsigned char *sha1,
dfefa935 886 int recursion)
0ebde32c 887{
064d51dc 888 int fd, len;
0ebde32c 889 char buffer[128], *p;
064d51dc 890 char *path;
0ebde32c 891
064d51dc 892 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 893 return -1;
064d51dc
MH
894 path = *refs->name
895 ? git_path_submodule(refs->name, "%s", refname)
896 : git_path("%s", refname);
897 fd = open(path, O_RDONLY);
0ebde32c 898 if (fd < 0)
b0626608 899 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
900
901 len = read(fd, buffer, sizeof(buffer)-1);
902 close(fd);
903 if (len < 0)
904 return -1;
905 while (len && isspace(buffer[len-1]))
906 len--;
907 buffer[len] = 0;
908
909 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 910 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
911 return 0;
912
913 /* Symref? */
914 if (strncmp(buffer, "ref:", 4))
915 return -1;
916 p = buffer + 4;
917 while (isspace(*p))
918 p++;
919
064d51dc 920 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
921}
922
85be1fe3 923int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
924{
925 int len = strlen(path), retval;
064d51dc 926 char *submodule;
b0626608 927 struct ref_cache *refs;
0ebde32c
LT
928
929 while (len && path[len-1] == '/')
930 len--;
931 if (!len)
932 return -1;
b0626608
MH
933 submodule = xstrndup(path, len);
934 refs = get_ref_cache(submodule);
935 free(submodule);
936
064d51dc 937 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
938 return retval;
939}
ca8db142 940
4886b89f 941/*
c224ca7f
MH
942 * Try to read ref from the packed references. On success, set sha1
943 * and return 0; otherwise, return -1.
4886b89f 944 */
dfefa935 945static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 946{
d3177275 947 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 948 struct ref_entry *entry = find_ref(packed, refname);
2c5c66be 949 if (entry) {
593f1bb8 950 hashcpy(sha1, entry->u.value.sha1);
2c5c66be 951 return 0;
c224ca7f
MH
952 }
953 return -1;
954}
955
8d68493f 956const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 957{
0104ca09
HO
958 int depth = MAXDEPTH;
959 ssize_t len;
a876ed83 960 char buffer[256];
dfefa935 961 static char refname_buffer[256];
ca8db142 962
8da19775
JH
963 if (flag)
964 *flag = 0;
965
dfefa935 966 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
967 return NULL;
968
a876ed83 969 for (;;) {
55956350 970 char path[PATH_MAX];
a876ed83
JH
971 struct stat st;
972 char *buf;
973 int fd;
8a65ff76 974
a876ed83
JH
975 if (--depth < 0)
976 return NULL;
ca8db142 977
dfefa935 978 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 979
a876ed83 980 if (lstat(path, &st) < 0) {
c224ca7f
MH
981 if (errno != ENOENT)
982 return NULL;
983 /*
984 * The loose reference file does not exist;
985 * check for a packed reference.
986 */
dfefa935 987 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
988 if (flag)
989 *flag |= REF_ISPACKED;
dfefa935 990 return refname;
434cd0cd 991 }
c224ca7f
MH
992 /* The reference is not a packed reference, either. */
993 if (reading) {
a876ed83 994 return NULL;
c224ca7f
MH
995 } else {
996 hashclr(sha1);
dfefa935 997 return refname;
c224ca7f 998 }
a876ed83 999 }
ca8db142 1000
a876ed83
JH
1001 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1002 if (S_ISLNK(st.st_mode)) {
1003 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
1004 if (len < 0)
1005 return NULL;
b54cb795 1006 buffer[len] = 0;
1f58a038
MH
1007 if (!prefixcmp(buffer, "refs/") &&
1008 !check_refname_format(buffer, 0)) {
dfefa935
MH
1009 strcpy(refname_buffer, buffer);
1010 refname = refname_buffer;
8da19775
JH
1011 if (flag)
1012 *flag |= REF_ISSYMREF;
a876ed83
JH
1013 continue;
1014 }
ca8db142 1015 }
a876ed83 1016
7a21632f
DS
1017 /* Is it a directory? */
1018 if (S_ISDIR(st.st_mode)) {
1019 errno = EISDIR;
1020 return NULL;
1021 }
1022
a876ed83
JH
1023 /*
1024 * Anything else, just open it and try to use it as
1025 * a ref
1026 */
1027 fd = open(path, O_RDONLY);
1028 if (fd < 0)
1029 return NULL;
93d26e4c 1030 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1031 close(fd);
28775050
MH
1032 if (len < 0)
1033 return NULL;
1034 while (len && isspace(buffer[len-1]))
1035 len--;
1036 buffer[len] = '\0';
a876ed83
JH
1037
1038 /*
1039 * Is it a symbolic ref?
1040 */
28775050 1041 if (prefixcmp(buffer, "ref:"))
a876ed83 1042 break;
55956350
JH
1043 if (flag)
1044 *flag |= REF_ISSYMREF;
a876ed83 1045 buf = buffer + 4;
28775050
MH
1046 while (isspace(*buf))
1047 buf++;
313fb010 1048 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1049 if (flag)
1050 *flag |= REF_ISBROKEN;
313fb010
MH
1051 return NULL;
1052 }
dfefa935 1053 refname = strcpy(refname_buffer, buf);
8a65ff76 1054 }
f989fea0
MH
1055 /* Please note that FETCH_HEAD has a second line containing other data. */
1056 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1057 if (flag)
1058 *flag |= REF_ISBROKEN;
a876ed83 1059 return NULL;
629cd3ac 1060 }
dfefa935 1061 return refname;
a876ed83
JH
1062}
1063
96ec7b1e
NTND
1064char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1065{
8cad4744 1066 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1067 return ret ? xstrdup(ret) : NULL;
1068}
1069
d08bae7e
IL
1070/* The argument to filter_refs */
1071struct ref_filter {
1072 const char *pattern;
1073 each_ref_fn *fn;
1074 void *cb_data;
1075};
1076
dfefa935 1077int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1078{
8d68493f 1079 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1080 return 0;
1081 return -1;
8a65ff76
LT
1082}
1083
dfefa935 1084int read_ref(const char *refname, unsigned char *sha1)
c6893323 1085{
dfefa935 1086 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1087}
1088
bc5fd6d3 1089int ref_exists(const char *refname)
ef06b918 1090{
bc5fd6d3
MH
1091 unsigned char sha1[20];
1092 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1093}
1094
85be1fe3 1095static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1096 void *data)
d08bae7e
IL
1097{
1098 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1099 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1100 return 0;
85be1fe3 1101 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1102}
1103
dfefa935 1104int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1105{
1106 int flag;
1107 unsigned char base[20];
1108 struct object *o;
1109
dfefa935
MH
1110 if (current_ref && (current_ref->name == refname
1111 || !strcmp(current_ref->name, refname))) {
0ae91be0 1112 if (current_ref->flag & REF_KNOWS_PEELED) {
593f1bb8 1113 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
1114 return 0;
1115 }
593f1bb8 1116 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
1117 goto fallback;
1118 }
1119
dfefa935 1120 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1121 return -1;
1122
1123 if ((flag & REF_ISPACKED)) {
d3177275 1124 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
432ad41e 1125 struct ref_entry *r = find_ref(dir, refname);
cf0adba7 1126
e9c4c111 1127 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
593f1bb8 1128 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1129 return 0;
cf0adba7 1130 }
cf0adba7
JH
1131 }
1132
0ae91be0 1133fallback:
cf0adba7 1134 o = parse_object(base);
8c87dc77 1135 if (o && o->type == OBJ_TAG) {
dfefa935 1136 o = deref_tag(o, refname, 0);
cf0adba7
JH
1137 if (o) {
1138 hashcpy(sha1, o->sha1);
1139 return 0;
1140 }
1141 }
1142 return -1;
1143}
1144
bc5fd6d3
MH
1145struct warn_if_dangling_data {
1146 FILE *fp;
1147 const char *refname;
1148 const char *msg_fmt;
1149};
1150
1151static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1152 int flags, void *cb_data)
1153{
1154 struct warn_if_dangling_data *d = cb_data;
1155 const char *resolves_to;
1156 unsigned char junk[20];
1157
1158 if (!(flags & REF_ISSYMREF))
1159 return 0;
1160
1161 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1162 if (!resolves_to || strcmp(resolves_to, d->refname))
1163 return 0;
1164
1165 fprintf(d->fp, d->msg_fmt, refname);
1166 return 0;
1167}
1168
1169void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1170{
1171 struct warn_if_dangling_data data;
1172
1173 data.fp = fp;
1174 data.refname = refname;
1175 data.msg_fmt = msg_fmt;
1176 for_each_rawref(warn_if_dangling_symref, &data);
1177}
1178
0bad611b
HV
1179static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1180 int trim, int flags, void *cb_data)
8a65ff76 1181{
316b097a 1182 struct ref_cache *refs = get_ref_cache(submodule);
933ac036
MH
1183 struct ref_dir *packed_dir = get_packed_refs(refs);
1184 struct ref_dir *loose_dir = get_loose_refs(refs);
1185 int retval = 0;
1186
1187 if (base && *base) {
1188 packed_dir = find_containing_dir(packed_dir, base, 0);
1189 loose_dir = find_containing_dir(loose_dir, base, 0);
1190 }
1191
1192 if (packed_dir && loose_dir) {
1193 sort_ref_dir(packed_dir);
1194 sort_ref_dir(loose_dir);
1195 retval = do_for_each_ref_in_dirs(
1196 packed_dir, loose_dir,
1197 base, fn, trim, flags, cb_data);
1198 } else if (packed_dir) {
1199 sort_ref_dir(packed_dir);
1200 retval = do_for_each_ref_in_dir(
1201 packed_dir, 0,
1202 base, fn, trim, flags, cb_data);
1203 } else if (loose_dir) {
1204 sort_ref_dir(loose_dir);
1205 retval = do_for_each_ref_in_dir(
1206 loose_dir, 0,
1207 base, fn, trim, flags, cb_data);
1208 }
1209
1210 return retval;
8a65ff76
LT
1211}
1212
0bad611b 1213static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1214{
1215 unsigned char sha1[20];
8da19775
JH
1216 int flag;
1217
0bad611b
HV
1218 if (submodule) {
1219 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1220 return fn("HEAD", sha1, 0, cb_data);
1221
1222 return 0;
1223 }
1224
c6893323 1225 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1226 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1227
2f34ba32 1228 return 0;
723c31fe
LT
1229}
1230
0bad611b
HV
1231int head_ref(each_ref_fn fn, void *cb_data)
1232{
1233 return do_head_ref(NULL, fn, cb_data);
1234}
1235
9ef6aeb0
HV
1236int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1237{
1238 return do_head_ref(submodule, fn, cb_data);
1239}
1240
cb5d709f 1241int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1242{
b3cfc406 1243 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1244}
1245
9ef6aeb0
HV
1246int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1247{
b3cfc406 1248 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1249}
1250
2a8177b6
CC
1251int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1252{
0bad611b 1253 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1254}
1255
9ef6aeb0
HV
1256int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1257 each_ref_fn fn, void *cb_data)
1258{
1259 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1260}
1261
cb5d709f 1262int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1263{
2a8177b6 1264 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1265}
1266
9ef6aeb0
HV
1267int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1268{
1269 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1270}
1271
cb5d709f 1272int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1273{
2a8177b6 1274 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1275}
1276
9ef6aeb0
HV
1277int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1278{
1279 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1280}
1281
cb5d709f 1282int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1283{
2a8177b6 1284 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1285}
1286
9ef6aeb0
HV
1287int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1288{
1289 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1290}
1291
29268700
CC
1292int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1293{
0bad611b 1294 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1295}
1296
a1bea2c1
JT
1297int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1298{
1299 struct strbuf buf = STRBUF_INIT;
1300 int ret = 0;
1301 unsigned char sha1[20];
1302 int flag;
1303
1304 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1305 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1306 ret = fn(buf.buf, sha1, flag, cb_data);
1307 strbuf_release(&buf);
1308
1309 return ret;
1310}
1311
1312int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1313{
1314 struct strbuf buf = STRBUF_INIT;
1315 int ret;
1316 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1317 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1318 strbuf_release(&buf);
1319 return ret;
1320}
1321
b09fe971
IL
1322int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1323 const char *prefix, void *cb_data)
d08bae7e
IL
1324{
1325 struct strbuf real_pattern = STRBUF_INIT;
1326 struct ref_filter filter;
d08bae7e
IL
1327 int ret;
1328
b09fe971 1329 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1330 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1331 else if (prefix)
1332 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1333 strbuf_addstr(&real_pattern, pattern);
1334
894a9d33 1335 if (!has_glob_specials(pattern)) {
9517e6b8 1336 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1337 if (real_pattern.buf[real_pattern.len - 1] != '/')
1338 strbuf_addch(&real_pattern, '/');
1339 /* No need to check for '*', there is none. */
1340 strbuf_addch(&real_pattern, '*');
1341 }
1342
1343 filter.pattern = real_pattern.buf;
1344 filter.fn = fn;
1345 filter.cb_data = cb_data;
1346 ret = for_each_ref(filter_refs, &filter);
1347
1348 strbuf_release(&real_pattern);
1349 return ret;
1350}
1351
b09fe971
IL
1352int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1353{
1354 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1355}
1356
f8948e2f
JH
1357int for_each_rawref(each_ref_fn fn, void *cb_data)
1358{
b3cfc406 1359 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1360 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1361}
1362
4577e483 1363const char *prettify_refname(const char *name)
a9c37a72 1364{
a9c37a72
DB
1365 return name + (
1366 !prefixcmp(name, "refs/heads/") ? 11 :
1367 !prefixcmp(name, "refs/tags/") ? 10 :
1368 !prefixcmp(name, "refs/remotes/") ? 13 :
1369 0);
1370}
1371
79803322
SP
1372const char *ref_rev_parse_rules[] = {
1373 "%.*s",
1374 "refs/%.*s",
1375 "refs/tags/%.*s",
1376 "refs/heads/%.*s",
1377 "refs/remotes/%.*s",
1378 "refs/remotes/%.*s/HEAD",
1379 NULL
1380};
1381
1382int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1383{
1384 const char **p;
1385 const int abbrev_name_len = strlen(abbrev_name);
1386
1387 for (p = rules; *p; p++) {
1388 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1389 return 1;
1390 }
1391 }
1392
1393 return 0;
1394}
1395
e5f38ec3 1396static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1397 const unsigned char *old_sha1, int mustexist)
1398{
c6893323 1399 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1400 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1401 unlock_ref(lock);
1402 return NULL;
1403 }
a89fccd2 1404 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1405 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1406 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1407 unlock_ref(lock);
1408 return NULL;
1409 }
1410 return lock;
1411}
1412
7155b727 1413static int remove_empty_directories(const char *file)
bc7127ef
JH
1414{
1415 /* we want to create a file but there is a directory there;
1416 * if that is an empty directory (or a directory that contains
1417 * only empty directories), remove them.
1418 */
7155b727
JS
1419 struct strbuf path;
1420 int result;
bc7127ef 1421
7155b727
JS
1422 strbuf_init(&path, 20);
1423 strbuf_addstr(&path, file);
1424
a0f4afbe 1425 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1426
1427 strbuf_release(&path);
1428
1429 return result;
bc7127ef
JH
1430}
1431
ff74f7f1
JH
1432/*
1433 * *string and *len will only be substituted, and *string returned (for
1434 * later free()ing) if the string passed in is a magic short-hand form
1435 * to name a branch.
1436 */
1437static char *substitute_branch_name(const char **string, int *len)
1438{
1439 struct strbuf buf = STRBUF_INIT;
1440 int ret = interpret_branch_name(*string, &buf);
1441
1442 if (ret == *len) {
1443 size_t size;
1444 *string = strbuf_detach(&buf, &size);
1445 *len = size;
1446 return (char *)*string;
1447 }
1448
1449 return NULL;
1450}
1451
1452int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1453{
1454 char *last_branch = substitute_branch_name(&str, &len);
1455 const char **p, *r;
1456 int refs_found = 0;
1457
1458 *ref = NULL;
1459 for (p = ref_rev_parse_rules; *p; p++) {
1460 char fullref[PATH_MAX];
1461 unsigned char sha1_from_ref[20];
1462 unsigned char *this_result;
1463 int flag;
1464
1465 this_result = refs_found ? sha1_from_ref : sha1;
1466 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1467 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1468 if (r) {
1469 if (!refs_found++)
1470 *ref = xstrdup(r);
1471 if (!warn_ambiguous_refs)
1472 break;
55956350 1473 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1474 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1475 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1476 warning("ignoring broken ref %s.", fullref);
1477 }
ff74f7f1
JH
1478 }
1479 free(last_branch);
1480 return refs_found;
1481}
1482
1483int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1484{
1485 char *last_branch = substitute_branch_name(&str, &len);
1486 const char **p;
1487 int logs_found = 0;
1488
1489 *log = NULL;
1490 for (p = ref_rev_parse_rules; *p; p++) {
1491 struct stat st;
1492 unsigned char hash[20];
1493 char path[PATH_MAX];
1494 const char *ref, *it;
1495
1496 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1497 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1498 if (!ref)
1499 continue;
1500 if (!stat(git_path("logs/%s", path), &st) &&
1501 S_ISREG(st.st_mode))
1502 it = path;
1503 else if (strcmp(ref, path) &&
1504 !stat(git_path("logs/%s", ref), &st) &&
1505 S_ISREG(st.st_mode))
1506 it = ref;
1507 else
1508 continue;
1509 if (!logs_found++) {
1510 *log = xstrdup(it);
1511 hashcpy(sha1, hash);
1512 }
1513 if (!warn_ambiguous_refs)
1514 break;
1515 }
1516 free(last_branch);
1517 return logs_found;
1518}
1519
dfefa935
MH
1520static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1521 const unsigned char *old_sha1,
1522 int flags, int *type_p)
4bd18c43 1523{
434cd0cd 1524 char *ref_file;
dfefa935 1525 const char *orig_refname = refname;
4bd18c43 1526 struct ref_lock *lock;
5cc3cef9 1527 int last_errno = 0;
acd3b9ec 1528 int type, lflags;
4431fcc4 1529 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1530 int missing = 0;
4bd18c43
SP
1531
1532 lock = xcalloc(1, sizeof(struct ref_lock));
1533 lock->lock_fd = -1;
1534
8d68493f 1535 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1536 if (!refname && errno == EISDIR) {
bc7127ef
JH
1537 /* we are trying to lock foo but we used to
1538 * have foo/bar which now does not exist;
1539 * it is normal for the empty directory 'foo'
1540 * to remain.
1541 */
dfefa935 1542 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1543 if (remove_empty_directories(ref_file)) {
1544 last_errno = errno;
dfefa935 1545 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1546 goto error_return;
1547 }
8d68493f 1548 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1549 }
68db31cc
SV
1550 if (type_p)
1551 *type_p = type;
dfefa935 1552 if (!refname) {
5cc3cef9 1553 last_errno = errno;
818f477c 1554 error("unable to resolve reference %s: %s",
dfefa935 1555 orig_refname, strerror(errno));
5cc3cef9 1556 goto error_return;
4bd18c43 1557 }
5bdd8d4a 1558 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1559 /* When the ref did not exist and we are creating it,
1560 * make sure there is no existing ref that is packed
1561 * whose name begins with our refname, nor a ref whose
1562 * name is a proper prefix of our refname.
1563 */
5bdd8d4a 1564 if (missing &&
316b097a 1565 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1566 last_errno = ENOTDIR;
c976d415 1567 goto error_return;
f475e08e 1568 }
22a3844e 1569
c33d5174 1570 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1571
acd3b9ec
JH
1572 lflags = LOCK_DIE_ON_ERROR;
1573 if (flags & REF_NODEREF) {
dfefa935 1574 refname = orig_refname;
acd3b9ec
JH
1575 lflags |= LOCK_NODEREF;
1576 }
dfefa935
MH
1577 lock->ref_name = xstrdup(refname);
1578 lock->orig_ref_name = xstrdup(orig_refname);
1579 ref_file = git_path("%s", refname);
5bdd8d4a 1580 if (missing)
68db31cc
SV
1581 lock->force_write = 1;
1582 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1583 lock->force_write = 1;
4bd18c43 1584
5cc3cef9
JH
1585 if (safe_create_leading_directories(ref_file)) {
1586 last_errno = errno;
1587 error("unable to create directory for %s", ref_file);
1588 goto error_return;
1589 }
4bd18c43 1590
acd3b9ec 1591 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1592 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1593
1594 error_return:
1595 unlock_ref(lock);
1596 errno = last_errno;
1597 return NULL;
4bd18c43
SP
1598}
1599
dfefa935 1600struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1601{
53cce84c 1602 char refpath[PATH_MAX];
dfefa935 1603 if (check_refname_format(refname, 0))
4bd18c43 1604 return NULL;
dfefa935 1605 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1606 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1607}
1608
dfefa935
MH
1609struct ref_lock *lock_any_ref_for_update(const char *refname,
1610 const unsigned char *old_sha1, int flags)
4bd18c43 1611{
dfefa935 1612 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1613 return NULL;
dfefa935 1614 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1615}
1616
d66da478
MH
1617struct repack_without_ref_sb {
1618 const char *refname;
1619 int fd;
1620};
1621
1622static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1623 int flags, void *cb_data)
1624{
1625 struct repack_without_ref_sb *data = cb_data;
1626 char line[PATH_MAX + 100];
1627 int len;
1628
1629 if (!strcmp(data->refname, refname))
1630 return 0;
1631 len = snprintf(line, sizeof(line), "%s %s\n",
1632 sha1_to_hex(sha1), refname);
1633 /* this should not happen but just being defensive */
1634 if (len > sizeof(line))
1635 die("too long a refname '%s'", refname);
1636 write_or_die(data->fd, line, len);
1637 return 0;
1638}
1639
26a063a1
JH
1640static struct lock_file packlock;
1641
c0277d15
JH
1642static int repack_without_ref(const char *refname)
1643{
d66da478 1644 struct repack_without_ref_sb data;
d3177275 1645 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 1646 if (find_ref(packed, refname) == NULL)
c0277d15 1647 return 0;
d66da478
MH
1648 data.refname = refname;
1649 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1650 if (data.fd < 0) {
1b018fd9 1651 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1652 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1653 }
d3177275 1654 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1655 return commit_lock_file(&packlock);
1656}
1657
eca35a25 1658int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1659{
1660 struct ref_lock *lock;
eca35a25 1661 int err, i = 0, ret = 0, flag = 0;
c0277d15 1662
68db31cc 1663 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1664 if (!lock)
1665 return 1;
045a476f 1666 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1667 /* loose */
eca35a25
MV
1668 const char *path;
1669
1670 if (!(delopt & REF_NODEREF)) {
1671 i = strlen(lock->lk->filename) - 5; /* .lock */
1672 lock->lk->filename[i] = 0;
1673 path = lock->lk->filename;
1674 } else {
9db56f71 1675 path = git_path("%s", refname);
eca35a25 1676 }
691f1a28
AR
1677 err = unlink_or_warn(path);
1678 if (err && errno != ENOENT)
c0277d15 1679 ret = 1;
691f1a28 1680
eca35a25
MV
1681 if (!(delopt & REF_NODEREF))
1682 lock->lk->filename[i] = '.';
c0277d15
JH
1683 }
1684 /* removing the loose one could have resurrected an earlier
1685 * packed one. Also, if it was not loose we need to repack
1686 * without it.
1687 */
1688 ret |= repack_without_ref(refname);
1689
691f1a28 1690 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1691 invalidate_ref_cache(NULL);
c0277d15
JH
1692 unlock_ref(lock);
1693 return ret;
4bd18c43
SP
1694}
1695
765c2258
PH
1696/*
1697 * People using contrib's git-new-workdir have .git/logs/refs ->
1698 * /some/other/path/.git/logs/refs, and that may live on another device.
1699 *
1700 * IOW, to avoid cross device rename errors, the temporary renamed log must
1701 * live into logs/refs.
1702 */
1703#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1704
dfefa935 1705int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1706{
c976d415
LH
1707 unsigned char sha1[20], orig_sha1[20];
1708 int flag = 0, logmoved = 0;
1709 struct ref_lock *lock;
c976d415 1710 struct stat loginfo;
dfefa935 1711 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1712 const char *symref = NULL;
316b097a 1713 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1714
450d4c0f 1715 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1716 return error("reflog for %s is a symlink", oldrefname);
c976d415 1717
8d68493f 1718 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1719 if (flag & REF_ISSYMREF)
fa58186c 1720 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1721 oldrefname);
eca35a25 1722 if (!symref)
dfefa935 1723 return error("refname %s not found", oldrefname);
c976d415 1724
316b097a 1725 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1726 return 1;
1727
316b097a 1728 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1729 return 1;
1730
dfefa935 1731 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1732 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1733 oldrefname, strerror(errno));
c976d415 1734
dfefa935
MH
1735 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1736 error("unable to delete old %s", oldrefname);
c976d415
LH
1737 goto rollback;
1738 }
1739
dfefa935
MH
1740 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1741 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1742 if (errno==EISDIR) {
dfefa935
MH
1743 if (remove_empty_directories(git_path("%s", newrefname))) {
1744 error("Directory not empty: %s", newrefname);
c976d415
LH
1745 goto rollback;
1746 }
1747 } else {
dfefa935 1748 error("unable to delete existing %s", newrefname);
c976d415
LH
1749 goto rollback;
1750 }
1751 }
1752
dfefa935
MH
1753 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1754 error("unable to create directory for %s", newrefname);
c976d415
LH
1755 goto rollback;
1756 }
1757
1758 retry:
dfefa935 1759 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1760 if (errno==EISDIR || errno==ENOTDIR) {
1761 /*
1762 * rename(a, b) when b is an existing
1763 * directory ought to result in ISDIR, but
1764 * Solaris 5.8 gives ENOTDIR. Sheesh.
1765 */
dfefa935
MH
1766 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1767 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1768 goto rollback;
1769 }
1770 goto retry;
1771 } else {
765c2258 1772 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1773 newrefname, strerror(errno));
c976d415
LH
1774 goto rollback;
1775 }
1776 }
1777 logmoved = log;
1778
dfefa935 1779 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1780 if (!lock) {
dfefa935 1781 error("unable to lock %s for update", newrefname);
c976d415
LH
1782 goto rollback;
1783 }
c976d415
LH
1784 lock->force_write = 1;
1785 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1786 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1787 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1788 goto rollback;
1789 }
1790
1791 return 0;
1792
1793 rollback:
dfefa935 1794 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1795 if (!lock) {
dfefa935 1796 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1797 goto rollbacklog;
1798 }
1799
1800 lock->force_write = 1;
1801 flag = log_all_ref_updates;
1802 log_all_ref_updates = 0;
1803 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1804 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1805 log_all_ref_updates = flag;
1806
1807 rollbacklog:
dfefa935 1808 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1809 error("unable to restore logfile %s from %s: %s",
dfefa935 1810 oldrefname, newrefname, strerror(errno));
c976d415 1811 if (!logmoved && log &&
dfefa935 1812 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1813 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1814 oldrefname, strerror(errno));
c976d415
LH
1815
1816 return 1;
1817}
1818
435fc852 1819int close_ref(struct ref_lock *lock)
b531394d
BC
1820{
1821 if (close_lock_file(lock->lk))
1822 return -1;
1823 lock->lock_fd = -1;
1824 return 0;
1825}
1826
435fc852 1827int commit_ref(struct ref_lock *lock)
b531394d
BC
1828{
1829 if (commit_lock_file(lock->lk))
1830 return -1;
1831 lock->lock_fd = -1;
1832 return 0;
1833}
1834
e5f38ec3 1835void unlock_ref(struct ref_lock *lock)
4bd18c43 1836{
4ed7cd3a
BC
1837 /* Do not free lock->lk -- atexit() still looks at them */
1838 if (lock->lk)
1839 rollback_lock_file(lock->lk);
434cd0cd 1840 free(lock->ref_name);
1655707c 1841 free(lock->orig_ref_name);
4bd18c43
SP
1842 free(lock);
1843}
1844
0ec29a47
JH
1845/*
1846 * copy the reflog message msg to buf, which has been allocated sufficiently
1847 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1848 * because reflog file is one line per entry.
1849 */
1850static int copy_msg(char *buf, const char *msg)
1851{
1852 char *cp = buf;
1853 char c;
1854 int wasspace = 1;
1855
1856 *cp++ = '\t';
1857 while ((c = *msg++)) {
1858 if (wasspace && isspace(c))
1859 continue;
1860 wasspace = isspace(c);
1861 if (wasspace)
1862 c = ' ';
1863 *cp++ = c;
1864 }
1865 while (buf < cp && isspace(cp[-1]))
1866 cp--;
1867 *cp++ = '\n';
1868 return cp - buf;
1869}
1870
dfefa935 1871int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 1872{
859c3017 1873 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1874
dfefa935 1875 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 1876 if (log_all_ref_updates &&
dfefa935
MH
1877 (!prefixcmp(refname, "refs/heads/") ||
1878 !prefixcmp(refname, "refs/remotes/") ||
1879 !prefixcmp(refname, "refs/notes/") ||
1880 !strcmp(refname, "HEAD"))) {
157aaea5 1881 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1882 return error("unable to create directory for %s",
157aaea5 1883 logfile);
6de08ae6
SP
1884 oflags |= O_CREAT;
1885 }
1886
157aaea5 1887 logfd = open(logfile, oflags, 0666);
6de08ae6 1888 if (logfd < 0) {
1974bf62 1889 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1890 return 0;
3b463c3f
JH
1891
1892 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1893 if (remove_empty_directories(logfile)) {
3b463c3f 1894 return error("There are still logs under '%s'",
157aaea5 1895 logfile);
3b463c3f 1896 }
157aaea5 1897 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1898 }
1899
1900 if (logfd < 0)
1901 return error("Unable to append to %s: %s",
157aaea5 1902 logfile, strerror(errno));
6de08ae6
SP
1903 }
1904
157aaea5 1905 adjust_shared_perm(logfile);
859c3017
EM
1906 close(logfd);
1907 return 0;
1908}
443b92b6 1909
dfefa935 1910static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
1911 const unsigned char *new_sha1, const char *msg)
1912{
1913 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1914 unsigned maxlen, len;
1915 int msglen;
157aaea5 1916 char log_file[PATH_MAX];
859c3017
EM
1917 char *logrec;
1918 const char *committer;
1919
1920 if (log_all_ref_updates < 0)
1921 log_all_ref_updates = !is_bare_repository();
1922
dfefa935 1923 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
1924 if (result)
1925 return result;
1926
1927 logfd = open(log_file, oflags);
1928 if (logfd < 0)
1929 return 0;
0ec29a47 1930 msglen = msg ? strlen(msg) : 0;
774751a8 1931 committer = git_committer_info(0);
8ac65937
JH
1932 maxlen = strlen(committer) + msglen + 100;
1933 logrec = xmalloc(maxlen);
1934 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1935 sha1_to_hex(old_sha1),
1936 sha1_to_hex(new_sha1),
8ac65937
JH
1937 committer);
1938 if (msglen)
0ec29a47 1939 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1940 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1941 free(logrec);
91c8d590 1942 if (close(logfd) != 0 || written != len)
9a13f0b7 1943 return error("Unable to append to %s", log_file);
6de08ae6
SP
1944 return 0;
1945}
1946
c3b0dec5
LT
1947static int is_branch(const char *refname)
1948{
1949 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1950}
1951
4bd18c43
SP
1952int write_ref_sha1(struct ref_lock *lock,
1953 const unsigned char *sha1, const char *logmsg)
1954{
1955 static char term = '\n';
c3b0dec5 1956 struct object *o;
4bd18c43
SP
1957
1958 if (!lock)
95fc7512 1959 return -1;
a89fccd2 1960 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1961 unlock_ref(lock);
1962 return 0;
95fc7512 1963 }
c3b0dec5
LT
1964 o = parse_object(sha1);
1965 if (!o) {
7be8b3ba 1966 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
1967 lock->ref_name, sha1_to_hex(sha1));
1968 unlock_ref(lock);
1969 return -1;
1970 }
1971 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1972 error("Trying to write non-commit object %s to branch %s",
1973 sha1_to_hex(sha1), lock->ref_name);
1974 unlock_ref(lock);
1975 return -1;
1976 }
93822c22
AW
1977 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1978 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1979 || close_ref(lock) < 0) {
c33d5174 1980 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1981 unlock_ref(lock);
1982 return -1;
1983 }
8bf90dc9 1984 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
1985 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1986 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1987 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1988 unlock_ref(lock);
1989 return -1;
1990 }
605fac8b
NP
1991 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1992 /*
1993 * Special hack: If a branch is updated directly and HEAD
1994 * points to it (may happen on the remote side of a push
1995 * for example) then logically the HEAD reflog should be
1996 * updated too.
1997 * A generic solution implies reverse symref information,
1998 * but finding all symrefs pointing to the given branch
1999 * would be rather costly for this rare event (the direct
2000 * update of a branch) to be worth it. So let's cheat and
2001 * check with HEAD only which should cover 99% of all usage
2002 * scenarios (even 100% of the default ones).
2003 */
2004 unsigned char head_sha1[20];
2005 int head_flag;
2006 const char *head_ref;
8cad4744 2007 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2008 if (head_ref && (head_flag & REF_ISSYMREF) &&
2009 !strcmp(head_ref, lock->ref_name))
2010 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2011 }
b531394d 2012 if (commit_ref(lock)) {
434cd0cd 2013 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2014 unlock_ref(lock);
2015 return -1;
2016 }
4bd18c43
SP
2017 unlock_ref(lock);
2018 return 0;
95fc7512 2019}
d556fae2 2020
8b5157e4
NP
2021int create_symref(const char *ref_target, const char *refs_heads_master,
2022 const char *logmsg)
41b625b0
NP
2023{
2024 const char *lockpath;
2025 char ref[1000];
2026 int fd, len, written;
a4f34cbb 2027 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2028 unsigned char old_sha1[20], new_sha1[20];
2029
2030 if (logmsg && read_ref(ref_target, old_sha1))
2031 hashclr(old_sha1);
41b625b0 2032
d48744d1
JH
2033 if (safe_create_leading_directories(git_HEAD) < 0)
2034 return error("unable to create directory for %s", git_HEAD);
2035
41b625b0
NP
2036#ifndef NO_SYMLINK_HEAD
2037 if (prefer_symlink_refs) {
2038 unlink(git_HEAD);
2039 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2040 goto done;
41b625b0
NP
2041 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2042 }
2043#endif
2044
2045 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2046 if (sizeof(ref) <= len) {
2047 error("refname too long: %s", refs_heads_master);
47fc52e2 2048 goto error_free_return;
41b625b0
NP
2049 }
2050 lockpath = mkpath("%s.lock", git_HEAD);
2051 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2052 if (fd < 0) {
2053 error("Unable to open %s for writing", lockpath);
47fc52e2 2054 goto error_free_return;
41b625b0
NP
2055 }
2056 written = write_in_full(fd, ref, len);
91c8d590 2057 if (close(fd) != 0 || written != len) {
41b625b0 2058 error("Unable to write to %s", lockpath);
47fc52e2 2059 goto error_unlink_return;
41b625b0
NP
2060 }
2061 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2062 error("Unable to create %s", git_HEAD);
47fc52e2 2063 goto error_unlink_return;
41b625b0
NP
2064 }
2065 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2066 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2067 error_unlink_return:
691f1a28 2068 unlink_or_warn(lockpath);
47fc52e2
JH
2069 error_free_return:
2070 free(git_HEAD);
2071 return -1;
41b625b0 2072 }
8b5157e4 2073
ee96d11b 2074#ifndef NO_SYMLINK_HEAD
8b5157e4 2075 done:
ee96d11b 2076#endif
8b5157e4
NP
2077 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2078 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2079
47fc52e2 2080 free(git_HEAD);
41b625b0
NP
2081 return 0;
2082}
2083
16d7cc90
JH
2084static char *ref_msg(const char *line, const char *endp)
2085{
2086 const char *ep;
16d7cc90 2087 line += 82;
182af834
PH
2088 ep = memchr(line, '\n', endp - line);
2089 if (!ep)
2090 ep = endp;
2091 return xmemdupz(line, ep - line);
16d7cc90
JH
2092}
2093
dfefa935
MH
2094int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2095 unsigned char *sha1, char **msg,
2096 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2097{
e5229042 2098 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2099 char *tz_c;
e29cb53a 2100 int logfd, tz, reccnt = 0;
d556fae2
SP
2101 struct stat st;
2102 unsigned long date;
e5229042 2103 unsigned char logged_sha1[20];
cb48cb58 2104 void *log_mapped;
dc49cd76 2105 size_t mapsz;
d556fae2 2106
dfefa935 2107 logfile = git_path("logs/%s", refname);
d556fae2
SP
2108 logfd = open(logfile, O_RDONLY, 0);
2109 if (logfd < 0)
d824cbba 2110 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2111 fstat(logfd, &st);
2112 if (!st.st_size)
2113 die("Log %s is empty.", logfile);
dc49cd76
SP
2114 mapsz = xsize_t(st.st_size);
2115 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2116 logdata = log_mapped;
d556fae2
SP
2117 close(logfd);
2118
e5229042 2119 lastrec = NULL;
d556fae2
SP
2120 rec = logend = logdata + st.st_size;
2121 while (logdata < rec) {
e29cb53a 2122 reccnt++;
d556fae2
SP
2123 if (logdata < rec && *(rec-1) == '\n')
2124 rec--;
e5229042
SP
2125 lastgt = NULL;
2126 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2127 rec--;
e5229042
SP
2128 if (*rec == '>')
2129 lastgt = rec;
2130 }
2131 if (!lastgt)
d556fae2 2132 die("Log %s is corrupt.", logfile);
e5229042 2133 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2134 if (date <= at_time || cnt == 0) {
76a44c5c 2135 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2136 if (msg)
2137 *msg = ref_msg(rec, logend);
2138 if (cutoff_time)
2139 *cutoff_time = date;
2140 if (cutoff_tz)
2141 *cutoff_tz = tz;
2142 if (cutoff_cnt)
76a44c5c 2143 *cutoff_cnt = reccnt - 1;
e5229042
SP
2144 if (lastrec) {
2145 if (get_sha1_hex(lastrec, logged_sha1))
2146 die("Log %s is corrupt.", logfile);
2147 if (get_sha1_hex(rec + 41, sha1))
2148 die("Log %s is corrupt.", logfile);
a89fccd2 2149 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2150 warning("Log %s has gap after %s.",
73013afd 2151 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2152 }
e5f38ec3
JH
2153 }
2154 else if (date == at_time) {
e5229042
SP
2155 if (get_sha1_hex(rec + 41, sha1))
2156 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2157 }
2158 else {
e5229042
SP
2159 if (get_sha1_hex(rec + 41, logged_sha1))
2160 die("Log %s is corrupt.", logfile);
a89fccd2 2161 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2162 warning("Log %s unexpectedly ended on %s.",
73013afd 2163 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2164 }
2165 }
dc49cd76 2166 munmap(log_mapped, mapsz);
d556fae2
SP
2167 return 0;
2168 }
e5229042 2169 lastrec = rec;
ab2a1a32
JH
2170 if (cnt > 0)
2171 cnt--;
d556fae2
SP
2172 }
2173
e5229042
SP
2174 rec = logdata;
2175 while (rec < logend && *rec != '>' && *rec != '\n')
2176 rec++;
2177 if (rec == logend || *rec == '\n')
d556fae2 2178 die("Log %s is corrupt.", logfile);
e5229042 2179 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2180 tz = strtoul(tz_c, NULL, 10);
2181 if (get_sha1_hex(logdata, sha1))
2182 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2183 if (is_null_sha1(sha1)) {
2184 if (get_sha1_hex(logdata + 41, sha1))
2185 die("Log %s is corrupt.", logfile);
2186 }
16d7cc90
JH
2187 if (msg)
2188 *msg = ref_msg(logdata, logend);
dc49cd76 2189 munmap(log_mapped, mapsz);
16d7cc90
JH
2190
2191 if (cutoff_time)
2192 *cutoff_time = date;
2193 if (cutoff_tz)
2194 *cutoff_tz = tz;
2195 if (cutoff_cnt)
2196 *cutoff_cnt = reccnt;
2197 return 1;
d556fae2 2198}
2ff81662 2199
dfefa935 2200int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
2201{
2202 const char *logfile;
2203 FILE *logfp;
8ca78803 2204 struct strbuf sb = STRBUF_INIT;
2266bf27 2205 int ret = 0;
2ff81662 2206
dfefa935 2207 logfile = git_path("logs/%s", refname);
2ff81662
JH
2208 logfp = fopen(logfile, "r");
2209 if (!logfp)
883d60fa 2210 return -1;
101d15e0
JH
2211
2212 if (ofs) {
2213 struct stat statbuf;
2214 if (fstat(fileno(logfp), &statbuf) ||
2215 statbuf.st_size < ofs ||
2216 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 2217 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 2218 fclose(logfp);
8ca78803 2219 strbuf_release(&sb);
101d15e0 2220 return -1;
9d33f7c2 2221 }
101d15e0
JH
2222 }
2223
8ca78803 2224 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 2225 unsigned char osha1[20], nsha1[20];
883d60fa
JS
2226 char *email_end, *message;
2227 unsigned long timestamp;
8ca78803 2228 int tz;
2ff81662
JH
2229
2230 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
2231 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2232 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2233 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2234 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
2235 email_end[1] != ' ' ||
2236 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2237 !message || message[0] != ' ' ||
2238 (message[1] != '+' && message[1] != '-') ||
2239 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2240 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2241 continue; /* corrupt? */
883d60fa
JS
2242 email_end[1] = '\0';
2243 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2244 if (message[6] != '\t')
2245 message += 6;
2246 else
2247 message += 7;
8ca78803
RS
2248 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2249 cb_data);
883d60fa 2250 if (ret)
2266bf27 2251 break;
2ff81662
JH
2252 }
2253 fclose(logfp);
8ca78803 2254 strbuf_release(&sb);
2266bf27 2255 return ret;
2ff81662 2256}
e29cb53a 2257
dfefa935 2258int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2259{
dfefa935 2260 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2261}
2262
989c0e5d
MH
2263/*
2264 * Call fn for each reflog in the namespace indicated by name. name
2265 * must be empty or end with '/'. Name will be used as a scratch
2266 * space, but its contents will be restored before return.
2267 */
2268static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 2269{
989c0e5d 2270 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 2271 int retval = 0;
93c603fc 2272 struct dirent *de;
989c0e5d 2273 int oldlen = name->len;
eb8381c8 2274
93c603fc 2275 if (!d)
989c0e5d 2276 return name->len ? errno : 0;
eb8381c8 2277
93c603fc
MH
2278 while ((de = readdir(d)) != NULL) {
2279 struct stat st;
eb8381c8 2280
93c603fc
MH
2281 if (de->d_name[0] == '.')
2282 continue;
93c603fc
MH
2283 if (has_extension(de->d_name, ".lock"))
2284 continue;
989c0e5d
MH
2285 strbuf_addstr(name, de->d_name);
2286 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2287 ; /* silently ignore */
93c603fc 2288 } else {
989c0e5d
MH
2289 if (S_ISDIR(st.st_mode)) {
2290 strbuf_addch(name, '/');
2291 retval = do_for_each_reflog(name, fn, cb_data);
2292 } else {
2293 unsigned char sha1[20];
2294 if (read_ref_full(name->buf, sha1, 0, NULL))
2295 retval = error("bad ref for %s", name->buf);
2296 else
2297 retval = fn(name->buf, sha1, 0, cb_data);
2298 }
2299 if (retval)
2300 break;
eb8381c8 2301 }
989c0e5d 2302 strbuf_setlen(name, oldlen);
eb8381c8 2303 }
93c603fc 2304 closedir(d);
eb8381c8
NP
2305 return retval;
2306}
2307
2308int for_each_reflog(each_ref_fn fn, void *cb_data)
2309{
989c0e5d
MH
2310 int retval;
2311 struct strbuf name;
2312 strbuf_init(&name, PATH_MAX);
2313 retval = do_for_each_reflog(&name, fn, cb_data);
2314 strbuf_release(&name);
2315 return retval;
eb8381c8 2316}
3d9f037c
CR
2317
2318int update_ref(const char *action, const char *refname,
2319 const unsigned char *sha1, const unsigned char *oldval,
2320 int flags, enum action_on_err onerr)
2321{
2322 static struct ref_lock *lock;
2323 lock = lock_any_ref_for_update(refname, oldval, flags);
2324 if (!lock) {
2325 const char *str = "Cannot lock the ref '%s'.";
2326 switch (onerr) {
2327 case MSG_ON_ERR: error(str, refname); break;
2328 case DIE_ON_ERR: die(str, refname); break;
2329 case QUIET_ON_ERR: break;
2330 }
2331 return 1;
2332 }
2333 if (write_ref_sha1(lock, sha1, action) < 0) {
2334 const char *str = "Cannot update the ref '%s'.";
2335 switch (onerr) {
2336 case MSG_ON_ERR: error(str, refname); break;
2337 case DIE_ON_ERR: die(str, refname); break;
2338 case QUIET_ON_ERR: break;
2339 }
2340 return 1;
2341 }
2342 return 0;
2343}
cda69f48 2344
5483f799 2345struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2346{
2347 for ( ; list; list = list->next)
2348 if (!strcmp(list->name, name))
5483f799 2349 return (struct ref *)list;
cda69f48
JK
2350 return NULL;
2351}
7c2b3029
JK
2352
2353/*
2354 * generate a format suitable for scanf from a ref_rev_parse_rules
2355 * rule, that is replace the "%.*s" spec with a "%s" spec
2356 */
2357static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2358{
2359 char *spec;
2360
2361 spec = strstr(rule, "%.*s");
2362 if (!spec || strstr(spec + 4, "%.*s"))
2363 die("invalid rule in ref_rev_parse_rules: %s", rule);
2364
2365 /* copy all until spec */
2366 strncpy(scanf_fmt, rule, spec - rule);
2367 scanf_fmt[spec - rule] = '\0';
2368 /* copy new spec */
2369 strcat(scanf_fmt, "%s");
2370 /* copy remaining rule */
2371 strcat(scanf_fmt, spec + 4);
2372
2373 return;
2374}
2375
dfefa935 2376char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2377{
2378 int i;
2379 static char **scanf_fmts;
2380 static int nr_rules;
2381 char *short_name;
2382
2383 /* pre generate scanf formats from ref_rev_parse_rules[] */
2384 if (!nr_rules) {
2385 size_t total_len = 0;
2386
2387 /* the rule list is NULL terminated, count them first */
2388 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2389 /* no +1 because strlen("%s") < strlen("%.*s") */
2390 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2391
2392 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2393
2394 total_len = 0;
2395 for (i = 0; i < nr_rules; i++) {
2396 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2397 + total_len;
2398 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2399 total_len += strlen(ref_rev_parse_rules[i]);
2400 }
2401 }
2402
2403 /* bail out if there are no rules */
2404 if (!nr_rules)
dfefa935 2405 return xstrdup(refname);
7c2b3029 2406
dfefa935
MH
2407 /* buffer for scanf result, at most refname must fit */
2408 short_name = xstrdup(refname);
7c2b3029
JK
2409
2410 /* skip first rule, it will always match */
2411 for (i = nr_rules - 1; i > 0 ; --i) {
2412 int j;
6e7b3309 2413 int rules_to_fail = i;
7c2b3029
JK
2414 int short_name_len;
2415
dfefa935 2416 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2417 continue;
2418
2419 short_name_len = strlen(short_name);
2420
6e7b3309
BW
2421 /*
2422 * in strict mode, all (except the matched one) rules
2423 * must fail to resolve to a valid non-ambiguous ref
2424 */
2425 if (strict)
2426 rules_to_fail = nr_rules;
2427
7c2b3029
JK
2428 /*
2429 * check if the short name resolves to a valid ref,
2430 * but use only rules prior to the matched one
2431 */
6e7b3309 2432 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2433 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2434 char refname[PATH_MAX];
2435
6e7b3309
BW
2436 /* skip matched rule */
2437 if (i == j)
2438 continue;
2439
7c2b3029
JK
2440 /*
2441 * the short name is ambiguous, if it resolves
2442 * (with this previous rule) to a valid ref
2443 * read_ref() returns 0 on success
2444 */
2445 mksnpath(refname, sizeof(refname),
2446 rule, short_name_len, short_name);
c6893323 2447 if (ref_exists(refname))
7c2b3029
JK
2448 break;
2449 }
2450
2451 /*
2452 * short name is non-ambiguous if all previous rules
2453 * haven't resolved to a valid ref
2454 */
6e7b3309 2455 if (j == rules_to_fail)
7c2b3029
JK
2456 return short_name;
2457 }
2458
2459 free(short_name);
dfefa935 2460 return xstrdup(refname);
7c2b3029 2461}