find_containing_dir(): use strbuf in implementation of this function
[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
f348ac92
MH
279/*
280 * Search for a directory entry directly within dir (without
281 * recursing). Sort dir if necessary. subdirname must be a directory
282 * name (i.e., end in '/'). If mkdir is set, then create the
283 * directory if it is missing; otherwise, return NULL if the desired
284 * directory cannot be found.
285 */
286static struct ref_entry *search_for_subdir(struct ref_dir *dir,
287 const char *subdirname, int mkdir)
288{
289 struct ref_entry *entry = search_ref_dir(dir, subdirname);
290 if (!entry) {
291 if (!mkdir)
292 return NULL;
293 entry = create_dir_entry(subdirname);
294 add_entry_to_dir(dir, entry);
295 }
296 assert(entry->flag & REF_DIR);
297 return entry;
298}
299
432ad41e
MH
300/*
301 * If refname is a reference name, find the ref_dir within the dir
302 * tree that should hold refname. If refname is a directory name
303 * (i.e., ends in '/'), then return that ref_dir itself. dir must
304 * represent the top-level directory. Sort ref_dirs and recurse into
305 * subdirectories as necessary. If mkdir is set, then create any
306 * missing directories; otherwise, return NULL if the desired
307 * directory cannot be found.
308 */
309static struct ref_dir *find_containing_dir(struct ref_dir *dir,
310 const char *refname, int mkdir)
311{
5fa04418
MH
312 struct strbuf dirname;
313 const char *slash;
314 strbuf_init(&dirname, PATH_MAX);
315 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
316 struct ref_entry *entry;
317 strbuf_add(&dirname,
318 refname + dirname.len,
319 (slash + 1) - (refname + dirname.len));
320 entry = search_for_subdir(dir, dirname.buf, mkdir);
f348ac92
MH
321 if (!entry)
322 break;
432ad41e
MH
323 dir = &entry->u.subdir;
324 }
325
5fa04418 326 strbuf_release(&dirname);
432ad41e
MH
327 return dir;
328}
329
330/*
331 * Find the value entry with the given name in dir, sorting ref_dirs
332 * and recursing into subdirectories as necessary. If the name is not
333 * found or it corresponds to a directory entry, return NULL.
334 */
335static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
336{
337 struct ref_entry *entry;
338 dir = find_containing_dir(dir, refname, 0);
339 if (!dir)
340 return NULL;
341 entry = search_ref_dir(dir, refname);
342 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
343}
344
345/*
346 * Add a ref_entry to the ref_dir (unsorted), recursing into
347 * subdirectories as necessary. dir must represent the top-level
348 * directory. Return 0 on success.
349 */
350static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
351{
352 dir = find_containing_dir(dir, ref->name, 1);
353 if (!dir)
354 return -1;
355 add_entry_to_dir(dir, ref);
356 return 0;
357}
358
202a56a9
MH
359/*
360 * Emit a warning and return true iff ref1 and ref2 have the same name
361 * and the same sha1. Die if they have the same name but different
362 * sha1s.
363 */
364static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
365{
432ad41e 366 if (strcmp(ref1->name, ref2->name))
202a56a9 367 return 0;
432ad41e
MH
368
369 /* Duplicate name; make sure that they don't conflict: */
370
371 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
372 /* This is impossible by construction */
373 die("Reference directory conflict: %s", ref1->name);
374
375 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
376 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
377
378 warning("Duplicated ref: %s", ref1->name);
379 return 1;
202a56a9
MH
380}
381
e6ed3ca6 382/*
432ad41e
MH
383 * Sort the entries in dir non-recursively (if they are not already
384 * sorted) and remove any duplicate entries.
e6ed3ca6 385 */
d3177275 386static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 387{
202a56a9 388 int i, j;
81a79d8e 389 struct ref_entry *last = NULL;
c774aab9 390
e6ed3ca6
MH
391 /*
392 * This check also prevents passing a zero-length array to qsort(),
393 * which is a problem on some platforms.
394 */
d3177275 395 if (dir->sorted == dir->nr)
e9c4c111 396 return;
c774aab9 397
d3177275 398 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 399
81a79d8e
MH
400 /* Remove any duplicates: */
401 for (i = 0, j = 0; j < dir->nr; j++) {
402 struct ref_entry *entry = dir->entries[j];
403 if (last && is_dup_ref(last, entry))
404 free_ref_entry(entry);
405 else
406 last = dir->entries[i++] = entry;
e9c4c111 407 }
81a79d8e 408 dir->sorted = dir->nr = i;
e9c4c111 409}
c774aab9 410
bc5fd6d3 411#define DO_FOR_EACH_INCLUDE_BROKEN 01
c774aab9 412
bc5fd6d3 413static struct ref_entry *current_ref;
c774aab9 414
bc5fd6d3
MH
415static int do_one_ref(const char *base, each_ref_fn fn, int trim,
416 int flags, void *cb_data, struct ref_entry *entry)
417{
429213e4 418 int retval;
bc5fd6d3
MH
419 if (prefixcmp(entry->name, base))
420 return 0;
c774aab9 421
bc5fd6d3
MH
422 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
423 if (entry->flag & REF_ISBROKEN)
424 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 425 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
426 error("%s does not point to a valid object!", entry->name);
427 return 0;
428 }
429 }
430 current_ref = entry;
593f1bb8 431 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
432 current_ref = NULL;
433 return retval;
bc5fd6d3 434}
c774aab9 435
c36b5bc2 436/*
d3177275 437 * Call fn for each reference in dir that has index in the range
432ad41e
MH
438 * offset <= index < dir->nr. Recurse into subdirectories that are in
439 * that index range, sorting them before iterating. This function
440 * does not sort dir itself; it should be sorted beforehand.
c36b5bc2 441 */
d3177275
MH
442static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
443 const char *base,
444 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
445{
446 int i;
d3177275
MH
447 assert(dir->sorted == dir->nr);
448 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
449 struct ref_entry *entry = dir->entries[i];
450 int retval;
451 if (entry->flag & REF_DIR) {
452 sort_ref_dir(&entry->u.subdir);
453 retval = do_for_each_ref_in_dir(&entry->u.subdir, 0,
454 base, fn, trim, flags, cb_data);
455 } else {
456 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
457 }
c36b5bc2
MH
458 if (retval)
459 return retval;
460 }
461 return 0;
462}
463
b3fd060f 464/*
d3177275 465 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
466 * by refname. Recurse into subdirectories. If a value entry appears
467 * in both dir1 and dir2, then only process the version that is in
468 * dir2. The input dirs must already be sorted, but subdirs will be
469 * sorted as needed.
b3fd060f 470 */
d3177275
MH
471static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
472 struct ref_dir *dir2,
473 const char *base, each_ref_fn fn, int trim,
474 int flags, void *cb_data)
b3fd060f
MH
475{
476 int retval;
477 int i1 = 0, i2 = 0;
478
d3177275
MH
479 assert(dir1->sorted == dir1->nr);
480 assert(dir2->sorted == dir2->nr);
432ad41e
MH
481 while (1) {
482 struct ref_entry *e1, *e2;
483 int cmp;
484 if (i1 == dir1->nr) {
485 return do_for_each_ref_in_dir(dir2, i2,
486 base, fn, trim, flags, cb_data);
487 }
488 if (i2 == dir2->nr) {
489 return do_for_each_ref_in_dir(dir1, i1,
490 base, fn, trim, flags, cb_data);
491 }
492 e1 = dir1->entries[i1];
493 e2 = dir2->entries[i2];
494 cmp = strcmp(e1->name, e2->name);
495 if (cmp == 0) {
496 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
497 /* Both are directories; descend them in parallel. */
498 sort_ref_dir(&e1->u.subdir);
499 sort_ref_dir(&e2->u.subdir);
500 retval = do_for_each_ref_in_dirs(
501 &e1->u.subdir, &e2->u.subdir,
502 base, fn, trim, flags, cb_data);
503 i1++;
504 i2++;
505 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
506 /* Both are references; ignore the one from dir1. */
507 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
508 i1++;
509 i2++;
510 } else {
511 die("conflict between reference and directory: %s",
512 e1->name);
513 }
b3fd060f 514 } else {
432ad41e
MH
515 struct ref_entry *e;
516 if (cmp < 0) {
517 e = e1;
b3fd060f 518 i1++;
432ad41e
MH
519 } else {
520 e = e2;
521 i2++;
522 }
523 if (e->flag & REF_DIR) {
524 sort_ref_dir(&e->u.subdir);
525 retval = do_for_each_ref_in_dir(
526 &e->u.subdir, 0,
527 base, fn, trim, flags, cb_data);
528 } else {
529 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
b3fd060f
MH
530 }
531 }
532 if (retval)
533 return retval;
534 }
d3177275
MH
535 if (i1 < dir1->nr)
536 return do_for_each_ref_in_dir(dir1, i1,
537 base, fn, trim, flags, cb_data);
538 if (i2 < dir2->nr)
539 return do_for_each_ref_in_dir(dir2, i2,
540 base, fn, trim, flags, cb_data);
b3fd060f
MH
541 return 0;
542}
543
d66da478
MH
544/*
545 * Return true iff refname1 and refname2 conflict with each other.
546 * Two reference names conflict if one of them exactly matches the
547 * leading components of the other; e.g., "foo/bar" conflicts with
548 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
549 * "foo/barbados".
550 */
551static int names_conflict(const char *refname1, const char *refname2)
552{
5a4d4947
MH
553 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
554 ;
555 return (*refname1 == '\0' && *refname2 == '/')
556 || (*refname1 == '/' && *refname2 == '\0');
557}
558
559struct name_conflict_cb {
560 const char *refname;
561 const char *oldrefname;
562 const char *conflicting_refname;
563};
564
565static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
566 int flags, void *cb_data)
567{
568 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
569 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
570 return 0;
571 if (names_conflict(data->refname, existingrefname)) {
572 data->conflicting_refname = existingrefname;
573 return 1;
d66da478 574 }
5a4d4947 575 return 0;
d66da478
MH
576}
577
bc5fd6d3
MH
578/*
579 * Return true iff a reference named refname could be created without
5a4d4947
MH
580 * conflicting with the name of an existing reference in array. If
581 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
582 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
583 * operation).
584 */
585static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 586 struct ref_dir *dir)
bc5fd6d3 587{
5a4d4947
MH
588 struct name_conflict_cb data;
589 data.refname = refname;
590 data.oldrefname = oldrefname;
591 data.conflicting_refname = NULL;
592
d3177275
MH
593 sort_ref_dir(dir);
594 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
595 0, DO_FOR_EACH_INCLUDE_BROKEN,
596 &data)) {
5a4d4947
MH
597 error("'%s' exists; cannot create '%s'",
598 data.conflicting_refname, refname);
599 return 0;
bc5fd6d3
MH
600 }
601 return 1;
e1e22e37
LT
602}
603
5e290ff7
JH
604/*
605 * Future: need to be in "struct repository"
606 * when doing a full libification.
607 */
79c7ca54
MH
608static struct ref_cache {
609 struct ref_cache *next;
5e290ff7
JH
610 char did_loose;
611 char did_packed;
d3177275
MH
612 struct ref_dir loose;
613 struct ref_dir packed;
ce40979c
MH
614 /* The submodule name, or "" for the main repo. */
615 char name[FLEX_ARRAY];
79c7ca54 616} *ref_cache;
0e88c130 617
760c4512 618static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 619{
1b7edaf9 620 if (refs->did_packed)
d3177275 621 clear_ref_dir(&refs->packed);
760c4512 622 refs->did_packed = 0;
5e290ff7 623}
e1e22e37 624
760c4512
MH
625static void clear_loose_ref_cache(struct ref_cache *refs)
626{
627 if (refs->did_loose)
d3177275 628 clear_ref_dir(&refs->loose);
760c4512
MH
629 refs->did_loose = 0;
630}
631
79c7ca54 632static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 633{
ce40979c 634 int len;
79c7ca54 635 struct ref_cache *refs;
ce40979c
MH
636 if (!submodule)
637 submodule = "";
638 len = strlen(submodule) + 1;
79c7ca54 639 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 640 memcpy(refs->name, submodule, len);
e5dbf605
MH
641 return refs;
642}
643
4349a668 644/*
79c7ca54 645 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
646 * the main repository, use submodule==NULL. The returned structure
647 * will be allocated and initialized but not necessarily populated; it
648 * should not be freed.
649 */
79c7ca54 650static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 651{
79c7ca54 652 struct ref_cache *refs = ref_cache;
0e88c130
MH
653 if (!submodule)
654 submodule = "";
655 while (refs) {
656 if (!strcmp(submodule, refs->name))
657 return refs;
658 refs = refs->next;
4349a668 659 }
0e88c130 660
79c7ca54
MH
661 refs = create_ref_cache(submodule);
662 refs->next = ref_cache;
663 ref_cache = refs;
0e88c130 664 return refs;
4349a668
MH
665}
666
8be8bde7 667void invalidate_ref_cache(const char *submodule)
f130b116 668{
c5f29abd
MH
669 struct ref_cache *refs = get_ref_cache(submodule);
670 clear_packed_ref_cache(refs);
671 clear_loose_ref_cache(refs);
5e290ff7 672}
e1e22e37 673
bc5fd6d3
MH
674/*
675 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
676 * Return a pointer to the refname within the line (null-terminated),
677 * or NULL if there was a problem.
678 */
679static const char *parse_ref_line(char *line, unsigned char *sha1)
680{
681 /*
682 * 42: the answer to everything.
683 *
684 * In this case, it happens to be the answer to
685 * 40 (length of sha1 hex representation)
686 * +1 (space in between hex and name)
687 * +1 (newline at the end of the line)
688 */
689 int len = strlen(line) - 42;
690
691 if (len <= 0)
692 return NULL;
693 if (get_sha1_hex(line, sha1) < 0)
694 return NULL;
695 if (!isspace(line[40]))
696 return NULL;
697 line += 41;
698 if (isspace(*line))
699 return NULL;
700 if (line[len] != '\n')
701 return NULL;
702 line[len] = 0;
703
704 return line;
705}
706
d3177275 707static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 708{
e9c4c111 709 struct ref_entry *last = NULL;
f4204ab9
JH
710 char refline[PATH_MAX];
711 int flag = REF_ISPACKED;
712
713 while (fgets(refline, sizeof(refline), f)) {
714 unsigned char sha1[20];
dfefa935 715 const char *refname;
f4204ab9
JH
716 static const char header[] = "# pack-refs with:";
717
718 if (!strncmp(refline, header, sizeof(header)-1)) {
719 const char *traits = refline + sizeof(header) - 1;
720 if (strstr(traits, " peeled "))
721 flag |= REF_KNOWS_PEELED;
722 /* perhaps other traits later as well */
723 continue;
724 }
725
dfefa935
MH
726 refname = parse_ref_line(refline, sha1);
727 if (refname) {
dd73ecd1 728 last = create_ref_entry(refname, sha1, flag, 1);
d3177275 729 add_ref(dir, last);
f4204ab9
JH
730 continue;
731 }
732 if (last &&
733 refline[0] == '^' &&
734 strlen(refline) == 42 &&
735 refline[41] == '\n' &&
736 !get_sha1_hex(refline + 1, sha1))
593f1bb8 737 hashcpy(last->u.value.peeled, sha1);
f4204ab9 738 }
f4204ab9
JH
739}
740
d3177275 741static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 742{
4349a668
MH
743 if (!refs->did_packed) {
744 const char *packed_refs_file;
745 FILE *f;
0bad611b 746
316b097a
MH
747 if (*refs->name)
748 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
749 else
750 packed_refs_file = git_path("packed-refs");
751 f = fopen(packed_refs_file, "r");
e1e22e37 752 if (f) {
2c5c66be 753 read_packed_refs(f, &refs->packed);
e1e22e37 754 fclose(f);
e1e22e37 755 }
0bad611b 756 refs->did_packed = 1;
e1e22e37 757 }
e9c4c111 758 return &refs->packed;
e1e22e37
LT
759}
760
30249ee6
MH
761void add_packed_ref(const char *refname, const unsigned char *sha1)
762{
763 add_ref(get_packed_refs(get_ref_cache(NULL)),
764 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
765}
766
abc39098
MH
767/*
768 * Read the loose references for refs from the namespace dirname.
9f2fb4a3
MH
769 * dirname must end with '/'. dir must be the directory entry
770 * corresponding to dirname.
abc39098 771 */
66a3d20b 772static void get_ref_dir(struct ref_cache *refs, const char *dirname,
d3177275 773 struct ref_dir *dir)
e1e22e37 774{
d3177275 775 DIR *d;
0bad611b 776 const char *path;
d5fdae67 777 struct dirent *de;
abc39098 778 int dirnamelen = strlen(dirname);
72b64b44 779 struct strbuf refname;
0bad611b 780
3b124823 781 if (*refs->name)
66a3d20b 782 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 783 else
66a3d20b 784 path = git_path("%s", dirname);
0bad611b 785
d3177275 786 d = opendir(path);
d5fdae67
MH
787 if (!d)
788 return;
789
66a3d20b
MH
790 strbuf_init(&refname, dirnamelen + 257);
791 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
792
793 while ((de = readdir(d)) != NULL) {
794 unsigned char sha1[20];
795 struct stat st;
796 int flag;
d5fdae67
MH
797 const char *refdir;
798
799 if (de->d_name[0] == '.')
800 continue;
d5fdae67
MH
801 if (has_extension(de->d_name, ".lock"))
802 continue;
72b64b44 803 strbuf_addstr(&refname, de->d_name);
d5fdae67 804 refdir = *refs->name
72b64b44
MH
805 ? git_path_submodule(refs->name, "%s", refname.buf)
806 : git_path("%s", refname.buf);
807 if (stat(refdir, &st) < 0) {
808 ; /* silently ignore */
809 } else if (S_ISDIR(st.st_mode)) {
abc39098 810 strbuf_addch(&refname, '/');
9f2fb4a3
MH
811 get_ref_dir(refs, refname.buf,
812 &search_for_subdir(dir, refname.buf, 1)->u.subdir);
72b64b44
MH
813 } else {
814 if (*refs->name) {
815 hashclr(sha1);
816 flag = 0;
817 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
818 hashclr(sha1);
819 flag |= REF_ISBROKEN;
820 }
821 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
822 hashclr(sha1);
823 flag |= REF_ISBROKEN;
824 }
9f2fb4a3
MH
825 add_entry_to_dir(dir,
826 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 827 }
66a3d20b 828 strbuf_setlen(&refname, dirnamelen);
e1e22e37 829 }
72b64b44 830 strbuf_release(&refname);
d5fdae67 831 closedir(d);
e1e22e37
LT
832}
833
d3177275 834static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 835{
4349a668 836 if (!refs->did_loose) {
9f2fb4a3
MH
837 get_ref_dir(refs, "refs/",
838 &search_for_subdir(&refs->loose, "refs/", 1)->u.subdir);
4349a668 839 refs->did_loose = 1;
e1e22e37 840 }
2c5c66be 841 return &refs->loose;
e1e22e37
LT
842}
843
ca8db142
LT
844/* We allow "recursive" symbolic refs. Only within reason, though */
845#define MAXDEPTH 5
0ebde32c
LT
846#define MAXREFLEN (1024)
847
e5fa45c1
JH
848/*
849 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
850 * from the loose refs in ref_cache refs. Find <refname> in the
851 * packed-refs file for the submodule.
e5fa45c1 852 */
b0626608 853static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 854 const char *refname, unsigned char *sha1)
0ebde32c 855{
2c5c66be 856 struct ref_entry *ref;
d3177275 857 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 858
432ad41e 859 ref = find_ref(dir, refname);
b0626608
MH
860 if (ref == NULL)
861 return -1;
862
593f1bb8 863 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 864 return 0;
0ebde32c
LT
865}
866
b0626608 867static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 868 const char *refname, unsigned char *sha1,
dfefa935 869 int recursion)
0ebde32c 870{
064d51dc 871 int fd, len;
0ebde32c 872 char buffer[128], *p;
064d51dc 873 char *path;
0ebde32c 874
064d51dc 875 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 876 return -1;
064d51dc
MH
877 path = *refs->name
878 ? git_path_submodule(refs->name, "%s", refname)
879 : git_path("%s", refname);
880 fd = open(path, O_RDONLY);
0ebde32c 881 if (fd < 0)
b0626608 882 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
883
884 len = read(fd, buffer, sizeof(buffer)-1);
885 close(fd);
886 if (len < 0)
887 return -1;
888 while (len && isspace(buffer[len-1]))
889 len--;
890 buffer[len] = 0;
891
892 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 893 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
894 return 0;
895
896 /* Symref? */
897 if (strncmp(buffer, "ref:", 4))
898 return -1;
899 p = buffer + 4;
900 while (isspace(*p))
901 p++;
902
064d51dc 903 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
904}
905
85be1fe3 906int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
907{
908 int len = strlen(path), retval;
064d51dc 909 char *submodule;
b0626608 910 struct ref_cache *refs;
0ebde32c
LT
911
912 while (len && path[len-1] == '/')
913 len--;
914 if (!len)
915 return -1;
b0626608
MH
916 submodule = xstrndup(path, len);
917 refs = get_ref_cache(submodule);
918 free(submodule);
919
064d51dc 920 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
921 return retval;
922}
ca8db142 923
4886b89f 924/*
c224ca7f
MH
925 * Try to read ref from the packed references. On success, set sha1
926 * and return 0; otherwise, return -1.
4886b89f 927 */
dfefa935 928static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 929{
d3177275 930 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 931 struct ref_entry *entry = find_ref(packed, refname);
2c5c66be 932 if (entry) {
593f1bb8 933 hashcpy(sha1, entry->u.value.sha1);
2c5c66be 934 return 0;
c224ca7f
MH
935 }
936 return -1;
937}
938
8d68493f 939const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 940{
0104ca09
HO
941 int depth = MAXDEPTH;
942 ssize_t len;
a876ed83 943 char buffer[256];
dfefa935 944 static char refname_buffer[256];
ca8db142 945
8da19775
JH
946 if (flag)
947 *flag = 0;
948
dfefa935 949 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
950 return NULL;
951
a876ed83 952 for (;;) {
55956350 953 char path[PATH_MAX];
a876ed83
JH
954 struct stat st;
955 char *buf;
956 int fd;
8a65ff76 957
a876ed83
JH
958 if (--depth < 0)
959 return NULL;
ca8db142 960
dfefa935 961 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 962
a876ed83 963 if (lstat(path, &st) < 0) {
c224ca7f
MH
964 if (errno != ENOENT)
965 return NULL;
966 /*
967 * The loose reference file does not exist;
968 * check for a packed reference.
969 */
dfefa935 970 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
971 if (flag)
972 *flag |= REF_ISPACKED;
dfefa935 973 return refname;
434cd0cd 974 }
c224ca7f
MH
975 /* The reference is not a packed reference, either. */
976 if (reading) {
a876ed83 977 return NULL;
c224ca7f
MH
978 } else {
979 hashclr(sha1);
dfefa935 980 return refname;
c224ca7f 981 }
a876ed83 982 }
ca8db142 983
a876ed83
JH
984 /* Follow "normalized" - ie "refs/.." symlinks by hand */
985 if (S_ISLNK(st.st_mode)) {
986 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
987 if (len < 0)
988 return NULL;
b54cb795 989 buffer[len] = 0;
1f58a038
MH
990 if (!prefixcmp(buffer, "refs/") &&
991 !check_refname_format(buffer, 0)) {
dfefa935
MH
992 strcpy(refname_buffer, buffer);
993 refname = refname_buffer;
8da19775
JH
994 if (flag)
995 *flag |= REF_ISSYMREF;
a876ed83
JH
996 continue;
997 }
ca8db142 998 }
a876ed83 999
7a21632f
DS
1000 /* Is it a directory? */
1001 if (S_ISDIR(st.st_mode)) {
1002 errno = EISDIR;
1003 return NULL;
1004 }
1005
a876ed83
JH
1006 /*
1007 * Anything else, just open it and try to use it as
1008 * a ref
1009 */
1010 fd = open(path, O_RDONLY);
1011 if (fd < 0)
1012 return NULL;
93d26e4c 1013 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1014 close(fd);
28775050
MH
1015 if (len < 0)
1016 return NULL;
1017 while (len && isspace(buffer[len-1]))
1018 len--;
1019 buffer[len] = '\0';
a876ed83
JH
1020
1021 /*
1022 * Is it a symbolic ref?
1023 */
28775050 1024 if (prefixcmp(buffer, "ref:"))
a876ed83 1025 break;
55956350
JH
1026 if (flag)
1027 *flag |= REF_ISSYMREF;
a876ed83 1028 buf = buffer + 4;
28775050
MH
1029 while (isspace(*buf))
1030 buf++;
313fb010 1031 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1032 if (flag)
1033 *flag |= REF_ISBROKEN;
313fb010
MH
1034 return NULL;
1035 }
dfefa935 1036 refname = strcpy(refname_buffer, buf);
8a65ff76 1037 }
f989fea0
MH
1038 /* Please note that FETCH_HEAD has a second line containing other data. */
1039 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1040 if (flag)
1041 *flag |= REF_ISBROKEN;
a876ed83 1042 return NULL;
629cd3ac 1043 }
dfefa935 1044 return refname;
a876ed83
JH
1045}
1046
96ec7b1e
NTND
1047char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1048{
8cad4744 1049 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1050 return ret ? xstrdup(ret) : NULL;
1051}
1052
d08bae7e
IL
1053/* The argument to filter_refs */
1054struct ref_filter {
1055 const char *pattern;
1056 each_ref_fn *fn;
1057 void *cb_data;
1058};
1059
dfefa935 1060int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1061{
8d68493f 1062 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1063 return 0;
1064 return -1;
8a65ff76
LT
1065}
1066
dfefa935 1067int read_ref(const char *refname, unsigned char *sha1)
c6893323 1068{
dfefa935 1069 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1070}
1071
bc5fd6d3 1072int ref_exists(const char *refname)
ef06b918 1073{
bc5fd6d3
MH
1074 unsigned char sha1[20];
1075 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1076}
1077
85be1fe3 1078static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1079 void *data)
d08bae7e
IL
1080{
1081 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1082 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1083 return 0;
85be1fe3 1084 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1085}
1086
dfefa935 1087int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1088{
1089 int flag;
1090 unsigned char base[20];
1091 struct object *o;
1092
dfefa935
MH
1093 if (current_ref && (current_ref->name == refname
1094 || !strcmp(current_ref->name, refname))) {
0ae91be0 1095 if (current_ref->flag & REF_KNOWS_PEELED) {
593f1bb8 1096 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
1097 return 0;
1098 }
593f1bb8 1099 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
1100 goto fallback;
1101 }
1102
dfefa935 1103 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1104 return -1;
1105
1106 if ((flag & REF_ISPACKED)) {
d3177275 1107 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
432ad41e 1108 struct ref_entry *r = find_ref(dir, refname);
cf0adba7 1109
e9c4c111 1110 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
593f1bb8 1111 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1112 return 0;
cf0adba7 1113 }
cf0adba7
JH
1114 }
1115
0ae91be0 1116fallback:
cf0adba7 1117 o = parse_object(base);
8c87dc77 1118 if (o && o->type == OBJ_TAG) {
dfefa935 1119 o = deref_tag(o, refname, 0);
cf0adba7
JH
1120 if (o) {
1121 hashcpy(sha1, o->sha1);
1122 return 0;
1123 }
1124 }
1125 return -1;
1126}
1127
bc5fd6d3
MH
1128struct warn_if_dangling_data {
1129 FILE *fp;
1130 const char *refname;
1131 const char *msg_fmt;
1132};
1133
1134static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1135 int flags, void *cb_data)
1136{
1137 struct warn_if_dangling_data *d = cb_data;
1138 const char *resolves_to;
1139 unsigned char junk[20];
1140
1141 if (!(flags & REF_ISSYMREF))
1142 return 0;
1143
1144 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1145 if (!resolves_to || strcmp(resolves_to, d->refname))
1146 return 0;
1147
1148 fprintf(d->fp, d->msg_fmt, refname);
1149 return 0;
1150}
1151
1152void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1153{
1154 struct warn_if_dangling_data data;
1155
1156 data.fp = fp;
1157 data.refname = refname;
1158 data.msg_fmt = msg_fmt;
1159 for_each_rawref(warn_if_dangling_symref, &data);
1160}
1161
0bad611b
HV
1162static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1163 int trim, int flags, void *cb_data)
8a65ff76 1164{
316b097a 1165 struct ref_cache *refs = get_ref_cache(submodule);
933ac036
MH
1166 struct ref_dir *packed_dir = get_packed_refs(refs);
1167 struct ref_dir *loose_dir = get_loose_refs(refs);
1168 int retval = 0;
1169
1170 if (base && *base) {
1171 packed_dir = find_containing_dir(packed_dir, base, 0);
1172 loose_dir = find_containing_dir(loose_dir, base, 0);
1173 }
1174
1175 if (packed_dir && loose_dir) {
1176 sort_ref_dir(packed_dir);
1177 sort_ref_dir(loose_dir);
1178 retval = do_for_each_ref_in_dirs(
1179 packed_dir, loose_dir,
1180 base, fn, trim, flags, cb_data);
1181 } else if (packed_dir) {
1182 sort_ref_dir(packed_dir);
1183 retval = do_for_each_ref_in_dir(
1184 packed_dir, 0,
1185 base, fn, trim, flags, cb_data);
1186 } else if (loose_dir) {
1187 sort_ref_dir(loose_dir);
1188 retval = do_for_each_ref_in_dir(
1189 loose_dir, 0,
1190 base, fn, trim, flags, cb_data);
1191 }
1192
1193 return retval;
8a65ff76
LT
1194}
1195
0bad611b 1196static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1197{
1198 unsigned char sha1[20];
8da19775
JH
1199 int flag;
1200
0bad611b
HV
1201 if (submodule) {
1202 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1203 return fn("HEAD", sha1, 0, cb_data);
1204
1205 return 0;
1206 }
1207
c6893323 1208 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1209 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1210
2f34ba32 1211 return 0;
723c31fe
LT
1212}
1213
0bad611b
HV
1214int head_ref(each_ref_fn fn, void *cb_data)
1215{
1216 return do_head_ref(NULL, fn, cb_data);
1217}
1218
9ef6aeb0
HV
1219int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1220{
1221 return do_head_ref(submodule, fn, cb_data);
1222}
1223
cb5d709f 1224int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1225{
b3cfc406 1226 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1227}
1228
9ef6aeb0
HV
1229int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1230{
b3cfc406 1231 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1232}
1233
2a8177b6
CC
1234int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1235{
0bad611b 1236 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1237}
1238
9ef6aeb0
HV
1239int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1240 each_ref_fn fn, void *cb_data)
1241{
1242 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1243}
1244
cb5d709f 1245int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1246{
2a8177b6 1247 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1248}
1249
9ef6aeb0
HV
1250int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1251{
1252 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1253}
1254
cb5d709f 1255int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1256{
2a8177b6 1257 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1258}
1259
9ef6aeb0
HV
1260int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1261{
1262 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1263}
1264
cb5d709f 1265int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1266{
2a8177b6 1267 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1268}
1269
9ef6aeb0
HV
1270int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1271{
1272 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1273}
1274
29268700
CC
1275int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1276{
0bad611b 1277 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1278}
1279
a1bea2c1
JT
1280int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1281{
1282 struct strbuf buf = STRBUF_INIT;
1283 int ret = 0;
1284 unsigned char sha1[20];
1285 int flag;
1286
1287 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1288 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1289 ret = fn(buf.buf, sha1, flag, cb_data);
1290 strbuf_release(&buf);
1291
1292 return ret;
1293}
1294
1295int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1296{
1297 struct strbuf buf = STRBUF_INIT;
1298 int ret;
1299 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1300 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1301 strbuf_release(&buf);
1302 return ret;
1303}
1304
b09fe971
IL
1305int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1306 const char *prefix, void *cb_data)
d08bae7e
IL
1307{
1308 struct strbuf real_pattern = STRBUF_INIT;
1309 struct ref_filter filter;
d08bae7e
IL
1310 int ret;
1311
b09fe971 1312 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1313 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1314 else if (prefix)
1315 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1316 strbuf_addstr(&real_pattern, pattern);
1317
894a9d33 1318 if (!has_glob_specials(pattern)) {
9517e6b8 1319 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1320 if (real_pattern.buf[real_pattern.len - 1] != '/')
1321 strbuf_addch(&real_pattern, '/');
1322 /* No need to check for '*', there is none. */
1323 strbuf_addch(&real_pattern, '*');
1324 }
1325
1326 filter.pattern = real_pattern.buf;
1327 filter.fn = fn;
1328 filter.cb_data = cb_data;
1329 ret = for_each_ref(filter_refs, &filter);
1330
1331 strbuf_release(&real_pattern);
1332 return ret;
1333}
1334
b09fe971
IL
1335int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1336{
1337 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1338}
1339
f8948e2f
JH
1340int for_each_rawref(each_ref_fn fn, void *cb_data)
1341{
b3cfc406 1342 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1343 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1344}
1345
4577e483 1346const char *prettify_refname(const char *name)
a9c37a72 1347{
a9c37a72
DB
1348 return name + (
1349 !prefixcmp(name, "refs/heads/") ? 11 :
1350 !prefixcmp(name, "refs/tags/") ? 10 :
1351 !prefixcmp(name, "refs/remotes/") ? 13 :
1352 0);
1353}
1354
79803322
SP
1355const char *ref_rev_parse_rules[] = {
1356 "%.*s",
1357 "refs/%.*s",
1358 "refs/tags/%.*s",
1359 "refs/heads/%.*s",
1360 "refs/remotes/%.*s",
1361 "refs/remotes/%.*s/HEAD",
1362 NULL
1363};
1364
1365int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1366{
1367 const char **p;
1368 const int abbrev_name_len = strlen(abbrev_name);
1369
1370 for (p = rules; *p; p++) {
1371 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1372 return 1;
1373 }
1374 }
1375
1376 return 0;
1377}
1378
e5f38ec3 1379static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1380 const unsigned char *old_sha1, int mustexist)
1381{
c6893323 1382 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1383 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1384 unlock_ref(lock);
1385 return NULL;
1386 }
a89fccd2 1387 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1388 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1389 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1390 unlock_ref(lock);
1391 return NULL;
1392 }
1393 return lock;
1394}
1395
7155b727 1396static int remove_empty_directories(const char *file)
bc7127ef
JH
1397{
1398 /* we want to create a file but there is a directory there;
1399 * if that is an empty directory (or a directory that contains
1400 * only empty directories), remove them.
1401 */
7155b727
JS
1402 struct strbuf path;
1403 int result;
bc7127ef 1404
7155b727
JS
1405 strbuf_init(&path, 20);
1406 strbuf_addstr(&path, file);
1407
a0f4afbe 1408 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1409
1410 strbuf_release(&path);
1411
1412 return result;
bc7127ef
JH
1413}
1414
ff74f7f1
JH
1415/*
1416 * *string and *len will only be substituted, and *string returned (for
1417 * later free()ing) if the string passed in is a magic short-hand form
1418 * to name a branch.
1419 */
1420static char *substitute_branch_name(const char **string, int *len)
1421{
1422 struct strbuf buf = STRBUF_INIT;
1423 int ret = interpret_branch_name(*string, &buf);
1424
1425 if (ret == *len) {
1426 size_t size;
1427 *string = strbuf_detach(&buf, &size);
1428 *len = size;
1429 return (char *)*string;
1430 }
1431
1432 return NULL;
1433}
1434
1435int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1436{
1437 char *last_branch = substitute_branch_name(&str, &len);
1438 const char **p, *r;
1439 int refs_found = 0;
1440
1441 *ref = NULL;
1442 for (p = ref_rev_parse_rules; *p; p++) {
1443 char fullref[PATH_MAX];
1444 unsigned char sha1_from_ref[20];
1445 unsigned char *this_result;
1446 int flag;
1447
1448 this_result = refs_found ? sha1_from_ref : sha1;
1449 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1450 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1451 if (r) {
1452 if (!refs_found++)
1453 *ref = xstrdup(r);
1454 if (!warn_ambiguous_refs)
1455 break;
55956350 1456 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1457 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1458 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1459 warning("ignoring broken ref %s.", fullref);
1460 }
ff74f7f1
JH
1461 }
1462 free(last_branch);
1463 return refs_found;
1464}
1465
1466int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1467{
1468 char *last_branch = substitute_branch_name(&str, &len);
1469 const char **p;
1470 int logs_found = 0;
1471
1472 *log = NULL;
1473 for (p = ref_rev_parse_rules; *p; p++) {
1474 struct stat st;
1475 unsigned char hash[20];
1476 char path[PATH_MAX];
1477 const char *ref, *it;
1478
1479 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1480 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1481 if (!ref)
1482 continue;
1483 if (!stat(git_path("logs/%s", path), &st) &&
1484 S_ISREG(st.st_mode))
1485 it = path;
1486 else if (strcmp(ref, path) &&
1487 !stat(git_path("logs/%s", ref), &st) &&
1488 S_ISREG(st.st_mode))
1489 it = ref;
1490 else
1491 continue;
1492 if (!logs_found++) {
1493 *log = xstrdup(it);
1494 hashcpy(sha1, hash);
1495 }
1496 if (!warn_ambiguous_refs)
1497 break;
1498 }
1499 free(last_branch);
1500 return logs_found;
1501}
1502
dfefa935
MH
1503static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1504 const unsigned char *old_sha1,
1505 int flags, int *type_p)
4bd18c43 1506{
434cd0cd 1507 char *ref_file;
dfefa935 1508 const char *orig_refname = refname;
4bd18c43 1509 struct ref_lock *lock;
5cc3cef9 1510 int last_errno = 0;
acd3b9ec 1511 int type, lflags;
4431fcc4 1512 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1513 int missing = 0;
4bd18c43
SP
1514
1515 lock = xcalloc(1, sizeof(struct ref_lock));
1516 lock->lock_fd = -1;
1517
8d68493f 1518 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1519 if (!refname && errno == EISDIR) {
bc7127ef
JH
1520 /* we are trying to lock foo but we used to
1521 * have foo/bar which now does not exist;
1522 * it is normal for the empty directory 'foo'
1523 * to remain.
1524 */
dfefa935 1525 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1526 if (remove_empty_directories(ref_file)) {
1527 last_errno = errno;
dfefa935 1528 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1529 goto error_return;
1530 }
8d68493f 1531 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1532 }
68db31cc
SV
1533 if (type_p)
1534 *type_p = type;
dfefa935 1535 if (!refname) {
5cc3cef9 1536 last_errno = errno;
818f477c 1537 error("unable to resolve reference %s: %s",
dfefa935 1538 orig_refname, strerror(errno));
5cc3cef9 1539 goto error_return;
4bd18c43 1540 }
5bdd8d4a 1541 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1542 /* When the ref did not exist and we are creating it,
1543 * make sure there is no existing ref that is packed
1544 * whose name begins with our refname, nor a ref whose
1545 * name is a proper prefix of our refname.
1546 */
5bdd8d4a 1547 if (missing &&
316b097a 1548 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1549 last_errno = ENOTDIR;
c976d415 1550 goto error_return;
f475e08e 1551 }
22a3844e 1552
c33d5174 1553 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1554
acd3b9ec
JH
1555 lflags = LOCK_DIE_ON_ERROR;
1556 if (flags & REF_NODEREF) {
dfefa935 1557 refname = orig_refname;
acd3b9ec
JH
1558 lflags |= LOCK_NODEREF;
1559 }
dfefa935
MH
1560 lock->ref_name = xstrdup(refname);
1561 lock->orig_ref_name = xstrdup(orig_refname);
1562 ref_file = git_path("%s", refname);
5bdd8d4a 1563 if (missing)
68db31cc
SV
1564 lock->force_write = 1;
1565 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1566 lock->force_write = 1;
4bd18c43 1567
5cc3cef9
JH
1568 if (safe_create_leading_directories(ref_file)) {
1569 last_errno = errno;
1570 error("unable to create directory for %s", ref_file);
1571 goto error_return;
1572 }
4bd18c43 1573
acd3b9ec 1574 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1575 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1576
1577 error_return:
1578 unlock_ref(lock);
1579 errno = last_errno;
1580 return NULL;
4bd18c43
SP
1581}
1582
dfefa935 1583struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1584{
53cce84c 1585 char refpath[PATH_MAX];
dfefa935 1586 if (check_refname_format(refname, 0))
4bd18c43 1587 return NULL;
dfefa935 1588 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1589 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1590}
1591
dfefa935
MH
1592struct ref_lock *lock_any_ref_for_update(const char *refname,
1593 const unsigned char *old_sha1, int flags)
4bd18c43 1594{
dfefa935 1595 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1596 return NULL;
dfefa935 1597 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1598}
1599
d66da478
MH
1600struct repack_without_ref_sb {
1601 const char *refname;
1602 int fd;
1603};
1604
1605static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1606 int flags, void *cb_data)
1607{
1608 struct repack_without_ref_sb *data = cb_data;
1609 char line[PATH_MAX + 100];
1610 int len;
1611
1612 if (!strcmp(data->refname, refname))
1613 return 0;
1614 len = snprintf(line, sizeof(line), "%s %s\n",
1615 sha1_to_hex(sha1), refname);
1616 /* this should not happen but just being defensive */
1617 if (len > sizeof(line))
1618 die("too long a refname '%s'", refname);
1619 write_or_die(data->fd, line, len);
1620 return 0;
1621}
1622
26a063a1
JH
1623static struct lock_file packlock;
1624
c0277d15
JH
1625static int repack_without_ref(const char *refname)
1626{
d66da478 1627 struct repack_without_ref_sb data;
d3177275 1628 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 1629 if (find_ref(packed, refname) == NULL)
c0277d15 1630 return 0;
d66da478
MH
1631 data.refname = refname;
1632 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1633 if (data.fd < 0) {
1b018fd9 1634 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1635 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1636 }
d3177275 1637 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1638 return commit_lock_file(&packlock);
1639}
1640
eca35a25 1641int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1642{
1643 struct ref_lock *lock;
eca35a25 1644 int err, i = 0, ret = 0, flag = 0;
c0277d15 1645
68db31cc 1646 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1647 if (!lock)
1648 return 1;
045a476f 1649 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1650 /* loose */
eca35a25
MV
1651 const char *path;
1652
1653 if (!(delopt & REF_NODEREF)) {
1654 i = strlen(lock->lk->filename) - 5; /* .lock */
1655 lock->lk->filename[i] = 0;
1656 path = lock->lk->filename;
1657 } else {
9db56f71 1658 path = git_path("%s", refname);
eca35a25 1659 }
691f1a28
AR
1660 err = unlink_or_warn(path);
1661 if (err && errno != ENOENT)
c0277d15 1662 ret = 1;
691f1a28 1663
eca35a25
MV
1664 if (!(delopt & REF_NODEREF))
1665 lock->lk->filename[i] = '.';
c0277d15
JH
1666 }
1667 /* removing the loose one could have resurrected an earlier
1668 * packed one. Also, if it was not loose we need to repack
1669 * without it.
1670 */
1671 ret |= repack_without_ref(refname);
1672
691f1a28 1673 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1674 invalidate_ref_cache(NULL);
c0277d15
JH
1675 unlock_ref(lock);
1676 return ret;
4bd18c43
SP
1677}
1678
765c2258
PH
1679/*
1680 * People using contrib's git-new-workdir have .git/logs/refs ->
1681 * /some/other/path/.git/logs/refs, and that may live on another device.
1682 *
1683 * IOW, to avoid cross device rename errors, the temporary renamed log must
1684 * live into logs/refs.
1685 */
1686#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1687
dfefa935 1688int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1689{
c976d415
LH
1690 unsigned char sha1[20], orig_sha1[20];
1691 int flag = 0, logmoved = 0;
1692 struct ref_lock *lock;
c976d415 1693 struct stat loginfo;
dfefa935 1694 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1695 const char *symref = NULL;
316b097a 1696 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1697
450d4c0f 1698 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1699 return error("reflog for %s is a symlink", oldrefname);
c976d415 1700
8d68493f 1701 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1702 if (flag & REF_ISSYMREF)
fa58186c 1703 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1704 oldrefname);
eca35a25 1705 if (!symref)
dfefa935 1706 return error("refname %s not found", oldrefname);
c976d415 1707
316b097a 1708 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1709 return 1;
1710
316b097a 1711 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1712 return 1;
1713
dfefa935 1714 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1715 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1716 oldrefname, strerror(errno));
c976d415 1717
dfefa935
MH
1718 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1719 error("unable to delete old %s", oldrefname);
c976d415
LH
1720 goto rollback;
1721 }
1722
dfefa935
MH
1723 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1724 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1725 if (errno==EISDIR) {
dfefa935
MH
1726 if (remove_empty_directories(git_path("%s", newrefname))) {
1727 error("Directory not empty: %s", newrefname);
c976d415
LH
1728 goto rollback;
1729 }
1730 } else {
dfefa935 1731 error("unable to delete existing %s", newrefname);
c976d415
LH
1732 goto rollback;
1733 }
1734 }
1735
dfefa935
MH
1736 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1737 error("unable to create directory for %s", newrefname);
c976d415
LH
1738 goto rollback;
1739 }
1740
1741 retry:
dfefa935 1742 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1743 if (errno==EISDIR || errno==ENOTDIR) {
1744 /*
1745 * rename(a, b) when b is an existing
1746 * directory ought to result in ISDIR, but
1747 * Solaris 5.8 gives ENOTDIR. Sheesh.
1748 */
dfefa935
MH
1749 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1750 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1751 goto rollback;
1752 }
1753 goto retry;
1754 } else {
765c2258 1755 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1756 newrefname, strerror(errno));
c976d415
LH
1757 goto rollback;
1758 }
1759 }
1760 logmoved = log;
1761
dfefa935 1762 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1763 if (!lock) {
dfefa935 1764 error("unable to lock %s for update", newrefname);
c976d415
LH
1765 goto rollback;
1766 }
c976d415
LH
1767 lock->force_write = 1;
1768 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1769 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1770 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1771 goto rollback;
1772 }
1773
1774 return 0;
1775
1776 rollback:
dfefa935 1777 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1778 if (!lock) {
dfefa935 1779 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1780 goto rollbacklog;
1781 }
1782
1783 lock->force_write = 1;
1784 flag = log_all_ref_updates;
1785 log_all_ref_updates = 0;
1786 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1787 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1788 log_all_ref_updates = flag;
1789
1790 rollbacklog:
dfefa935 1791 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1792 error("unable to restore logfile %s from %s: %s",
dfefa935 1793 oldrefname, newrefname, strerror(errno));
c976d415 1794 if (!logmoved && log &&
dfefa935 1795 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1796 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1797 oldrefname, strerror(errno));
c976d415
LH
1798
1799 return 1;
1800}
1801
435fc852 1802int close_ref(struct ref_lock *lock)
b531394d
BC
1803{
1804 if (close_lock_file(lock->lk))
1805 return -1;
1806 lock->lock_fd = -1;
1807 return 0;
1808}
1809
435fc852 1810int commit_ref(struct ref_lock *lock)
b531394d
BC
1811{
1812 if (commit_lock_file(lock->lk))
1813 return -1;
1814 lock->lock_fd = -1;
1815 return 0;
1816}
1817
e5f38ec3 1818void unlock_ref(struct ref_lock *lock)
4bd18c43 1819{
4ed7cd3a
BC
1820 /* Do not free lock->lk -- atexit() still looks at them */
1821 if (lock->lk)
1822 rollback_lock_file(lock->lk);
434cd0cd 1823 free(lock->ref_name);
1655707c 1824 free(lock->orig_ref_name);
4bd18c43
SP
1825 free(lock);
1826}
1827
0ec29a47
JH
1828/*
1829 * copy the reflog message msg to buf, which has been allocated sufficiently
1830 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1831 * because reflog file is one line per entry.
1832 */
1833static int copy_msg(char *buf, const char *msg)
1834{
1835 char *cp = buf;
1836 char c;
1837 int wasspace = 1;
1838
1839 *cp++ = '\t';
1840 while ((c = *msg++)) {
1841 if (wasspace && isspace(c))
1842 continue;
1843 wasspace = isspace(c);
1844 if (wasspace)
1845 c = ' ';
1846 *cp++ = c;
1847 }
1848 while (buf < cp && isspace(cp[-1]))
1849 cp--;
1850 *cp++ = '\n';
1851 return cp - buf;
1852}
1853
dfefa935 1854int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 1855{
859c3017 1856 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1857
dfefa935 1858 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 1859 if (log_all_ref_updates &&
dfefa935
MH
1860 (!prefixcmp(refname, "refs/heads/") ||
1861 !prefixcmp(refname, "refs/remotes/") ||
1862 !prefixcmp(refname, "refs/notes/") ||
1863 !strcmp(refname, "HEAD"))) {
157aaea5 1864 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1865 return error("unable to create directory for %s",
157aaea5 1866 logfile);
6de08ae6
SP
1867 oflags |= O_CREAT;
1868 }
1869
157aaea5 1870 logfd = open(logfile, oflags, 0666);
6de08ae6 1871 if (logfd < 0) {
1974bf62 1872 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1873 return 0;
3b463c3f
JH
1874
1875 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1876 if (remove_empty_directories(logfile)) {
3b463c3f 1877 return error("There are still logs under '%s'",
157aaea5 1878 logfile);
3b463c3f 1879 }
157aaea5 1880 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1881 }
1882
1883 if (logfd < 0)
1884 return error("Unable to append to %s: %s",
157aaea5 1885 logfile, strerror(errno));
6de08ae6
SP
1886 }
1887
157aaea5 1888 adjust_shared_perm(logfile);
859c3017
EM
1889 close(logfd);
1890 return 0;
1891}
443b92b6 1892
dfefa935 1893static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
1894 const unsigned char *new_sha1, const char *msg)
1895{
1896 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1897 unsigned maxlen, len;
1898 int msglen;
157aaea5 1899 char log_file[PATH_MAX];
859c3017
EM
1900 char *logrec;
1901 const char *committer;
1902
1903 if (log_all_ref_updates < 0)
1904 log_all_ref_updates = !is_bare_repository();
1905
dfefa935 1906 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
1907 if (result)
1908 return result;
1909
1910 logfd = open(log_file, oflags);
1911 if (logfd < 0)
1912 return 0;
0ec29a47 1913 msglen = msg ? strlen(msg) : 0;
774751a8 1914 committer = git_committer_info(0);
8ac65937
JH
1915 maxlen = strlen(committer) + msglen + 100;
1916 logrec = xmalloc(maxlen);
1917 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1918 sha1_to_hex(old_sha1),
1919 sha1_to_hex(new_sha1),
8ac65937
JH
1920 committer);
1921 if (msglen)
0ec29a47 1922 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1923 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1924 free(logrec);
91c8d590 1925 if (close(logfd) != 0 || written != len)
9a13f0b7 1926 return error("Unable to append to %s", log_file);
6de08ae6
SP
1927 return 0;
1928}
1929
c3b0dec5
LT
1930static int is_branch(const char *refname)
1931{
1932 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1933}
1934
4bd18c43
SP
1935int write_ref_sha1(struct ref_lock *lock,
1936 const unsigned char *sha1, const char *logmsg)
1937{
1938 static char term = '\n';
c3b0dec5 1939 struct object *o;
4bd18c43
SP
1940
1941 if (!lock)
95fc7512 1942 return -1;
a89fccd2 1943 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1944 unlock_ref(lock);
1945 return 0;
95fc7512 1946 }
c3b0dec5
LT
1947 o = parse_object(sha1);
1948 if (!o) {
7be8b3ba 1949 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
1950 lock->ref_name, sha1_to_hex(sha1));
1951 unlock_ref(lock);
1952 return -1;
1953 }
1954 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1955 error("Trying to write non-commit object %s to branch %s",
1956 sha1_to_hex(sha1), lock->ref_name);
1957 unlock_ref(lock);
1958 return -1;
1959 }
93822c22
AW
1960 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1961 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1962 || close_ref(lock) < 0) {
c33d5174 1963 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1964 unlock_ref(lock);
1965 return -1;
1966 }
8bf90dc9 1967 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
1968 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1969 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1970 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1971 unlock_ref(lock);
1972 return -1;
1973 }
605fac8b
NP
1974 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1975 /*
1976 * Special hack: If a branch is updated directly and HEAD
1977 * points to it (may happen on the remote side of a push
1978 * for example) then logically the HEAD reflog should be
1979 * updated too.
1980 * A generic solution implies reverse symref information,
1981 * but finding all symrefs pointing to the given branch
1982 * would be rather costly for this rare event (the direct
1983 * update of a branch) to be worth it. So let's cheat and
1984 * check with HEAD only which should cover 99% of all usage
1985 * scenarios (even 100% of the default ones).
1986 */
1987 unsigned char head_sha1[20];
1988 int head_flag;
1989 const char *head_ref;
8cad4744 1990 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
1991 if (head_ref && (head_flag & REF_ISSYMREF) &&
1992 !strcmp(head_ref, lock->ref_name))
1993 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1994 }
b531394d 1995 if (commit_ref(lock)) {
434cd0cd 1996 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1997 unlock_ref(lock);
1998 return -1;
1999 }
4bd18c43
SP
2000 unlock_ref(lock);
2001 return 0;
95fc7512 2002}
d556fae2 2003
8b5157e4
NP
2004int create_symref(const char *ref_target, const char *refs_heads_master,
2005 const char *logmsg)
41b625b0
NP
2006{
2007 const char *lockpath;
2008 char ref[1000];
2009 int fd, len, written;
a4f34cbb 2010 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2011 unsigned char old_sha1[20], new_sha1[20];
2012
2013 if (logmsg && read_ref(ref_target, old_sha1))
2014 hashclr(old_sha1);
41b625b0 2015
d48744d1
JH
2016 if (safe_create_leading_directories(git_HEAD) < 0)
2017 return error("unable to create directory for %s", git_HEAD);
2018
41b625b0
NP
2019#ifndef NO_SYMLINK_HEAD
2020 if (prefer_symlink_refs) {
2021 unlink(git_HEAD);
2022 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2023 goto done;
41b625b0
NP
2024 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2025 }
2026#endif
2027
2028 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2029 if (sizeof(ref) <= len) {
2030 error("refname too long: %s", refs_heads_master);
47fc52e2 2031 goto error_free_return;
41b625b0
NP
2032 }
2033 lockpath = mkpath("%s.lock", git_HEAD);
2034 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2035 if (fd < 0) {
2036 error("Unable to open %s for writing", lockpath);
47fc52e2 2037 goto error_free_return;
41b625b0
NP
2038 }
2039 written = write_in_full(fd, ref, len);
91c8d590 2040 if (close(fd) != 0 || written != len) {
41b625b0 2041 error("Unable to write to %s", lockpath);
47fc52e2 2042 goto error_unlink_return;
41b625b0
NP
2043 }
2044 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2045 error("Unable to create %s", git_HEAD);
47fc52e2 2046 goto error_unlink_return;
41b625b0
NP
2047 }
2048 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2049 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2050 error_unlink_return:
691f1a28 2051 unlink_or_warn(lockpath);
47fc52e2
JH
2052 error_free_return:
2053 free(git_HEAD);
2054 return -1;
41b625b0 2055 }
8b5157e4 2056
ee96d11b 2057#ifndef NO_SYMLINK_HEAD
8b5157e4 2058 done:
ee96d11b 2059#endif
8b5157e4
NP
2060 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2061 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2062
47fc52e2 2063 free(git_HEAD);
41b625b0
NP
2064 return 0;
2065}
2066
16d7cc90
JH
2067static char *ref_msg(const char *line, const char *endp)
2068{
2069 const char *ep;
16d7cc90 2070 line += 82;
182af834
PH
2071 ep = memchr(line, '\n', endp - line);
2072 if (!ep)
2073 ep = endp;
2074 return xmemdupz(line, ep - line);
16d7cc90
JH
2075}
2076
dfefa935
MH
2077int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2078 unsigned char *sha1, char **msg,
2079 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2080{
e5229042 2081 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2082 char *tz_c;
e29cb53a 2083 int logfd, tz, reccnt = 0;
d556fae2
SP
2084 struct stat st;
2085 unsigned long date;
e5229042 2086 unsigned char logged_sha1[20];
cb48cb58 2087 void *log_mapped;
dc49cd76 2088 size_t mapsz;
d556fae2 2089
dfefa935 2090 logfile = git_path("logs/%s", refname);
d556fae2
SP
2091 logfd = open(logfile, O_RDONLY, 0);
2092 if (logfd < 0)
d824cbba 2093 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2094 fstat(logfd, &st);
2095 if (!st.st_size)
2096 die("Log %s is empty.", logfile);
dc49cd76
SP
2097 mapsz = xsize_t(st.st_size);
2098 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2099 logdata = log_mapped;
d556fae2
SP
2100 close(logfd);
2101
e5229042 2102 lastrec = NULL;
d556fae2
SP
2103 rec = logend = logdata + st.st_size;
2104 while (logdata < rec) {
e29cb53a 2105 reccnt++;
d556fae2
SP
2106 if (logdata < rec && *(rec-1) == '\n')
2107 rec--;
e5229042
SP
2108 lastgt = NULL;
2109 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2110 rec--;
e5229042
SP
2111 if (*rec == '>')
2112 lastgt = rec;
2113 }
2114 if (!lastgt)
d556fae2 2115 die("Log %s is corrupt.", logfile);
e5229042 2116 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2117 if (date <= at_time || cnt == 0) {
76a44c5c 2118 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2119 if (msg)
2120 *msg = ref_msg(rec, logend);
2121 if (cutoff_time)
2122 *cutoff_time = date;
2123 if (cutoff_tz)
2124 *cutoff_tz = tz;
2125 if (cutoff_cnt)
76a44c5c 2126 *cutoff_cnt = reccnt - 1;
e5229042
SP
2127 if (lastrec) {
2128 if (get_sha1_hex(lastrec, logged_sha1))
2129 die("Log %s is corrupt.", logfile);
2130 if (get_sha1_hex(rec + 41, sha1))
2131 die("Log %s is corrupt.", logfile);
a89fccd2 2132 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2133 warning("Log %s has gap after %s.",
73013afd 2134 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2135 }
e5f38ec3
JH
2136 }
2137 else if (date == at_time) {
e5229042
SP
2138 if (get_sha1_hex(rec + 41, sha1))
2139 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2140 }
2141 else {
e5229042
SP
2142 if (get_sha1_hex(rec + 41, logged_sha1))
2143 die("Log %s is corrupt.", logfile);
a89fccd2 2144 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2145 warning("Log %s unexpectedly ended on %s.",
73013afd 2146 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2147 }
2148 }
dc49cd76 2149 munmap(log_mapped, mapsz);
d556fae2
SP
2150 return 0;
2151 }
e5229042 2152 lastrec = rec;
ab2a1a32
JH
2153 if (cnt > 0)
2154 cnt--;
d556fae2
SP
2155 }
2156
e5229042
SP
2157 rec = logdata;
2158 while (rec < logend && *rec != '>' && *rec != '\n')
2159 rec++;
2160 if (rec == logend || *rec == '\n')
d556fae2 2161 die("Log %s is corrupt.", logfile);
e5229042 2162 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2163 tz = strtoul(tz_c, NULL, 10);
2164 if (get_sha1_hex(logdata, sha1))
2165 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2166 if (is_null_sha1(sha1)) {
2167 if (get_sha1_hex(logdata + 41, sha1))
2168 die("Log %s is corrupt.", logfile);
2169 }
16d7cc90
JH
2170 if (msg)
2171 *msg = ref_msg(logdata, logend);
dc49cd76 2172 munmap(log_mapped, mapsz);
16d7cc90
JH
2173
2174 if (cutoff_time)
2175 *cutoff_time = date;
2176 if (cutoff_tz)
2177 *cutoff_tz = tz;
2178 if (cutoff_cnt)
2179 *cutoff_cnt = reccnt;
2180 return 1;
d556fae2 2181}
2ff81662 2182
dfefa935 2183int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
2184{
2185 const char *logfile;
2186 FILE *logfp;
8ca78803 2187 struct strbuf sb = STRBUF_INIT;
2266bf27 2188 int ret = 0;
2ff81662 2189
dfefa935 2190 logfile = git_path("logs/%s", refname);
2ff81662
JH
2191 logfp = fopen(logfile, "r");
2192 if (!logfp)
883d60fa 2193 return -1;
101d15e0
JH
2194
2195 if (ofs) {
2196 struct stat statbuf;
2197 if (fstat(fileno(logfp), &statbuf) ||
2198 statbuf.st_size < ofs ||
2199 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 2200 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 2201 fclose(logfp);
8ca78803 2202 strbuf_release(&sb);
101d15e0 2203 return -1;
9d33f7c2 2204 }
101d15e0
JH
2205 }
2206
8ca78803 2207 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 2208 unsigned char osha1[20], nsha1[20];
883d60fa
JS
2209 char *email_end, *message;
2210 unsigned long timestamp;
8ca78803 2211 int tz;
2ff81662
JH
2212
2213 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
2214 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2215 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2216 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2217 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
2218 email_end[1] != ' ' ||
2219 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2220 !message || message[0] != ' ' ||
2221 (message[1] != '+' && message[1] != '-') ||
2222 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2223 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2224 continue; /* corrupt? */
883d60fa
JS
2225 email_end[1] = '\0';
2226 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2227 if (message[6] != '\t')
2228 message += 6;
2229 else
2230 message += 7;
8ca78803
RS
2231 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2232 cb_data);
883d60fa 2233 if (ret)
2266bf27 2234 break;
2ff81662
JH
2235 }
2236 fclose(logfp);
8ca78803 2237 strbuf_release(&sb);
2266bf27 2238 return ret;
2ff81662 2239}
e29cb53a 2240
dfefa935 2241int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2242{
dfefa935 2243 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2244}
2245
989c0e5d
MH
2246/*
2247 * Call fn for each reflog in the namespace indicated by name. name
2248 * must be empty or end with '/'. Name will be used as a scratch
2249 * space, but its contents will be restored before return.
2250 */
2251static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 2252{
989c0e5d 2253 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 2254 int retval = 0;
93c603fc 2255 struct dirent *de;
989c0e5d 2256 int oldlen = name->len;
eb8381c8 2257
93c603fc 2258 if (!d)
989c0e5d 2259 return name->len ? errno : 0;
eb8381c8 2260
93c603fc
MH
2261 while ((de = readdir(d)) != NULL) {
2262 struct stat st;
eb8381c8 2263
93c603fc
MH
2264 if (de->d_name[0] == '.')
2265 continue;
93c603fc
MH
2266 if (has_extension(de->d_name, ".lock"))
2267 continue;
989c0e5d
MH
2268 strbuf_addstr(name, de->d_name);
2269 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2270 ; /* silently ignore */
93c603fc 2271 } else {
989c0e5d
MH
2272 if (S_ISDIR(st.st_mode)) {
2273 strbuf_addch(name, '/');
2274 retval = do_for_each_reflog(name, fn, cb_data);
2275 } else {
2276 unsigned char sha1[20];
2277 if (read_ref_full(name->buf, sha1, 0, NULL))
2278 retval = error("bad ref for %s", name->buf);
2279 else
2280 retval = fn(name->buf, sha1, 0, cb_data);
2281 }
2282 if (retval)
2283 break;
eb8381c8 2284 }
989c0e5d 2285 strbuf_setlen(name, oldlen);
eb8381c8 2286 }
93c603fc 2287 closedir(d);
eb8381c8
NP
2288 return retval;
2289}
2290
2291int for_each_reflog(each_ref_fn fn, void *cb_data)
2292{
989c0e5d
MH
2293 int retval;
2294 struct strbuf name;
2295 strbuf_init(&name, PATH_MAX);
2296 retval = do_for_each_reflog(&name, fn, cb_data);
2297 strbuf_release(&name);
2298 return retval;
eb8381c8 2299}
3d9f037c
CR
2300
2301int update_ref(const char *action, const char *refname,
2302 const unsigned char *sha1, const unsigned char *oldval,
2303 int flags, enum action_on_err onerr)
2304{
2305 static struct ref_lock *lock;
2306 lock = lock_any_ref_for_update(refname, oldval, flags);
2307 if (!lock) {
2308 const char *str = "Cannot lock the ref '%s'.";
2309 switch (onerr) {
2310 case MSG_ON_ERR: error(str, refname); break;
2311 case DIE_ON_ERR: die(str, refname); break;
2312 case QUIET_ON_ERR: break;
2313 }
2314 return 1;
2315 }
2316 if (write_ref_sha1(lock, sha1, action) < 0) {
2317 const char *str = "Cannot update the ref '%s'.";
2318 switch (onerr) {
2319 case MSG_ON_ERR: error(str, refname); break;
2320 case DIE_ON_ERR: die(str, refname); break;
2321 case QUIET_ON_ERR: break;
2322 }
2323 return 1;
2324 }
2325 return 0;
2326}
cda69f48 2327
5483f799 2328struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2329{
2330 for ( ; list; list = list->next)
2331 if (!strcmp(list->name, name))
5483f799 2332 return (struct ref *)list;
cda69f48
JK
2333 return NULL;
2334}
7c2b3029
JK
2335
2336/*
2337 * generate a format suitable for scanf from a ref_rev_parse_rules
2338 * rule, that is replace the "%.*s" spec with a "%s" spec
2339 */
2340static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2341{
2342 char *spec;
2343
2344 spec = strstr(rule, "%.*s");
2345 if (!spec || strstr(spec + 4, "%.*s"))
2346 die("invalid rule in ref_rev_parse_rules: %s", rule);
2347
2348 /* copy all until spec */
2349 strncpy(scanf_fmt, rule, spec - rule);
2350 scanf_fmt[spec - rule] = '\0';
2351 /* copy new spec */
2352 strcat(scanf_fmt, "%s");
2353 /* copy remaining rule */
2354 strcat(scanf_fmt, spec + 4);
2355
2356 return;
2357}
2358
dfefa935 2359char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2360{
2361 int i;
2362 static char **scanf_fmts;
2363 static int nr_rules;
2364 char *short_name;
2365
2366 /* pre generate scanf formats from ref_rev_parse_rules[] */
2367 if (!nr_rules) {
2368 size_t total_len = 0;
2369
2370 /* the rule list is NULL terminated, count them first */
2371 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2372 /* no +1 because strlen("%s") < strlen("%.*s") */
2373 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2374
2375 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2376
2377 total_len = 0;
2378 for (i = 0; i < nr_rules; i++) {
2379 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2380 + total_len;
2381 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2382 total_len += strlen(ref_rev_parse_rules[i]);
2383 }
2384 }
2385
2386 /* bail out if there are no rules */
2387 if (!nr_rules)
dfefa935 2388 return xstrdup(refname);
7c2b3029 2389
dfefa935
MH
2390 /* buffer for scanf result, at most refname must fit */
2391 short_name = xstrdup(refname);
7c2b3029
JK
2392
2393 /* skip first rule, it will always match */
2394 for (i = nr_rules - 1; i > 0 ; --i) {
2395 int j;
6e7b3309 2396 int rules_to_fail = i;
7c2b3029
JK
2397 int short_name_len;
2398
dfefa935 2399 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2400 continue;
2401
2402 short_name_len = strlen(short_name);
2403
6e7b3309
BW
2404 /*
2405 * in strict mode, all (except the matched one) rules
2406 * must fail to resolve to a valid non-ambiguous ref
2407 */
2408 if (strict)
2409 rules_to_fail = nr_rules;
2410
7c2b3029
JK
2411 /*
2412 * check if the short name resolves to a valid ref,
2413 * but use only rules prior to the matched one
2414 */
6e7b3309 2415 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2416 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2417 char refname[PATH_MAX];
2418
6e7b3309
BW
2419 /* skip matched rule */
2420 if (i == j)
2421 continue;
2422
7c2b3029
JK
2423 /*
2424 * the short name is ambiguous, if it resolves
2425 * (with this previous rule) to a valid ref
2426 * read_ref() returns 0 on success
2427 */
2428 mksnpath(refname, sizeof(refname),
2429 rule, short_name_len, short_name);
c6893323 2430 if (ref_exists(refname))
7c2b3029
JK
2431 break;
2432 }
2433
2434 /*
2435 * short name is non-ambiguous if all previous rules
2436 * haven't resolved to a valid ref
2437 */
6e7b3309 2438 if (j == rules_to_fail)
7c2b3029
JK
2439 return short_name;
2440 }
2441
2442 free(short_name);
dfefa935 2443 return xstrdup(refname);
7c2b3029 2444}