do_for_each_reflog(): return early on error
[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{
312 char *refname_copy = xstrdup(refname);
313 char *slash;
314 struct ref_entry *entry;
315 for (slash = strchr(refname_copy, '/'); slash; slash = strchr(slash + 1, '/')) {
316 char tmp = slash[1];
317 slash[1] = '\0';
f348ac92 318 entry = search_for_subdir(dir, refname_copy, mkdir);
432ad41e 319 slash[1] = tmp;
f348ac92
MH
320 if (!entry)
321 break;
432ad41e
MH
322 dir = &entry->u.subdir;
323 }
324
325 free(refname_copy);
326 return dir;
327}
328
329/*
330 * Find the value entry with the given name in dir, sorting ref_dirs
331 * and recursing into subdirectories as necessary. If the name is not
332 * found or it corresponds to a directory entry, return NULL.
333 */
334static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
335{
336 struct ref_entry *entry;
337 dir = find_containing_dir(dir, refname, 0);
338 if (!dir)
339 return NULL;
340 entry = search_ref_dir(dir, refname);
341 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
342}
343
344/*
345 * Add a ref_entry to the ref_dir (unsorted), recursing into
346 * subdirectories as necessary. dir must represent the top-level
347 * directory. Return 0 on success.
348 */
349static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
350{
351 dir = find_containing_dir(dir, ref->name, 1);
352 if (!dir)
353 return -1;
354 add_entry_to_dir(dir, ref);
355 return 0;
356}
357
202a56a9
MH
358/*
359 * Emit a warning and return true iff ref1 and ref2 have the same name
360 * and the same sha1. Die if they have the same name but different
361 * sha1s.
362 */
363static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
364{
432ad41e 365 if (strcmp(ref1->name, ref2->name))
202a56a9 366 return 0;
432ad41e
MH
367
368 /* Duplicate name; make sure that they don't conflict: */
369
370 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
371 /* This is impossible by construction */
372 die("Reference directory conflict: %s", ref1->name);
373
374 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
375 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
376
377 warning("Duplicated ref: %s", ref1->name);
378 return 1;
202a56a9
MH
379}
380
e6ed3ca6 381/*
432ad41e
MH
382 * Sort the entries in dir non-recursively (if they are not already
383 * sorted) and remove any duplicate entries.
e6ed3ca6 384 */
d3177275 385static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 386{
202a56a9 387 int i, j;
81a79d8e 388 struct ref_entry *last = NULL;
c774aab9 389
e6ed3ca6
MH
390 /*
391 * This check also prevents passing a zero-length array to qsort(),
392 * which is a problem on some platforms.
393 */
d3177275 394 if (dir->sorted == dir->nr)
e9c4c111 395 return;
c774aab9 396
d3177275 397 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 398
81a79d8e
MH
399 /* Remove any duplicates: */
400 for (i = 0, j = 0; j < dir->nr; j++) {
401 struct ref_entry *entry = dir->entries[j];
402 if (last && is_dup_ref(last, entry))
403 free_ref_entry(entry);
404 else
405 last = dir->entries[i++] = entry;
e9c4c111 406 }
81a79d8e 407 dir->sorted = dir->nr = i;
e9c4c111 408}
c774aab9 409
bc5fd6d3 410#define DO_FOR_EACH_INCLUDE_BROKEN 01
c774aab9 411
bc5fd6d3 412static struct ref_entry *current_ref;
c774aab9 413
bc5fd6d3
MH
414static int do_one_ref(const char *base, each_ref_fn fn, int trim,
415 int flags, void *cb_data, struct ref_entry *entry)
416{
429213e4 417 int retval;
bc5fd6d3
MH
418 if (prefixcmp(entry->name, base))
419 return 0;
c774aab9 420
bc5fd6d3
MH
421 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
422 if (entry->flag & REF_ISBROKEN)
423 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 424 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
425 error("%s does not point to a valid object!", entry->name);
426 return 0;
427 }
428 }
429 current_ref = entry;
593f1bb8 430 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
431 current_ref = NULL;
432 return retval;
bc5fd6d3 433}
c774aab9 434
c36b5bc2 435/*
d3177275 436 * Call fn for each reference in dir that has index in the range
432ad41e
MH
437 * offset <= index < dir->nr. Recurse into subdirectories that are in
438 * that index range, sorting them before iterating. This function
439 * does not sort dir itself; it should be sorted beforehand.
c36b5bc2 440 */
d3177275
MH
441static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
442 const char *base,
443 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
444{
445 int i;
d3177275
MH
446 assert(dir->sorted == dir->nr);
447 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
448 struct ref_entry *entry = dir->entries[i];
449 int retval;
450 if (entry->flag & REF_DIR) {
451 sort_ref_dir(&entry->u.subdir);
452 retval = do_for_each_ref_in_dir(&entry->u.subdir, 0,
453 base, fn, trim, flags, cb_data);
454 } else {
455 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
456 }
c36b5bc2
MH
457 if (retval)
458 return retval;
459 }
460 return 0;
461}
462
b3fd060f 463/*
d3177275 464 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
465 * by refname. Recurse into subdirectories. If a value entry appears
466 * in both dir1 and dir2, then only process the version that is in
467 * dir2. The input dirs must already be sorted, but subdirs will be
468 * sorted as needed.
b3fd060f 469 */
d3177275
MH
470static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
471 struct ref_dir *dir2,
472 const char *base, each_ref_fn fn, int trim,
473 int flags, void *cb_data)
b3fd060f
MH
474{
475 int retval;
476 int i1 = 0, i2 = 0;
477
d3177275
MH
478 assert(dir1->sorted == dir1->nr);
479 assert(dir2->sorted == dir2->nr);
432ad41e
MH
480 while (1) {
481 struct ref_entry *e1, *e2;
482 int cmp;
483 if (i1 == dir1->nr) {
484 return do_for_each_ref_in_dir(dir2, i2,
485 base, fn, trim, flags, cb_data);
486 }
487 if (i2 == dir2->nr) {
488 return do_for_each_ref_in_dir(dir1, i1,
489 base, fn, trim, flags, cb_data);
490 }
491 e1 = dir1->entries[i1];
492 e2 = dir2->entries[i2];
493 cmp = strcmp(e1->name, e2->name);
494 if (cmp == 0) {
495 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
496 /* Both are directories; descend them in parallel. */
497 sort_ref_dir(&e1->u.subdir);
498 sort_ref_dir(&e2->u.subdir);
499 retval = do_for_each_ref_in_dirs(
500 &e1->u.subdir, &e2->u.subdir,
501 base, fn, trim, flags, cb_data);
502 i1++;
503 i2++;
504 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
505 /* Both are references; ignore the one from dir1. */
506 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
507 i1++;
508 i2++;
509 } else {
510 die("conflict between reference and directory: %s",
511 e1->name);
512 }
b3fd060f 513 } else {
432ad41e
MH
514 struct ref_entry *e;
515 if (cmp < 0) {
516 e = e1;
b3fd060f 517 i1++;
432ad41e
MH
518 } else {
519 e = e2;
520 i2++;
521 }
522 if (e->flag & REF_DIR) {
523 sort_ref_dir(&e->u.subdir);
524 retval = do_for_each_ref_in_dir(
525 &e->u.subdir, 0,
526 base, fn, trim, flags, cb_data);
527 } else {
528 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
b3fd060f
MH
529 }
530 }
531 if (retval)
532 return retval;
533 }
d3177275
MH
534 if (i1 < dir1->nr)
535 return do_for_each_ref_in_dir(dir1, i1,
536 base, fn, trim, flags, cb_data);
537 if (i2 < dir2->nr)
538 return do_for_each_ref_in_dir(dir2, i2,
539 base, fn, trim, flags, cb_data);
b3fd060f
MH
540 return 0;
541}
542
d66da478
MH
543/*
544 * Return true iff refname1 and refname2 conflict with each other.
545 * Two reference names conflict if one of them exactly matches the
546 * leading components of the other; e.g., "foo/bar" conflicts with
547 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
548 * "foo/barbados".
549 */
550static int names_conflict(const char *refname1, const char *refname2)
551{
5a4d4947
MH
552 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
553 ;
554 return (*refname1 == '\0' && *refname2 == '/')
555 || (*refname1 == '/' && *refname2 == '\0');
556}
557
558struct name_conflict_cb {
559 const char *refname;
560 const char *oldrefname;
561 const char *conflicting_refname;
562};
563
564static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
565 int flags, void *cb_data)
566{
567 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
568 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
569 return 0;
570 if (names_conflict(data->refname, existingrefname)) {
571 data->conflicting_refname = existingrefname;
572 return 1;
d66da478 573 }
5a4d4947 574 return 0;
d66da478
MH
575}
576
bc5fd6d3
MH
577/*
578 * Return true iff a reference named refname could be created without
5a4d4947
MH
579 * conflicting with the name of an existing reference in array. If
580 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
581 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
582 * operation).
583 */
584static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 585 struct ref_dir *dir)
bc5fd6d3 586{
5a4d4947
MH
587 struct name_conflict_cb data;
588 data.refname = refname;
589 data.oldrefname = oldrefname;
590 data.conflicting_refname = NULL;
591
d3177275
MH
592 sort_ref_dir(dir);
593 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
594 0, DO_FOR_EACH_INCLUDE_BROKEN,
595 &data)) {
5a4d4947
MH
596 error("'%s' exists; cannot create '%s'",
597 data.conflicting_refname, refname);
598 return 0;
bc5fd6d3
MH
599 }
600 return 1;
e1e22e37
LT
601}
602
5e290ff7
JH
603/*
604 * Future: need to be in "struct repository"
605 * when doing a full libification.
606 */
79c7ca54
MH
607static struct ref_cache {
608 struct ref_cache *next;
5e290ff7
JH
609 char did_loose;
610 char did_packed;
d3177275
MH
611 struct ref_dir loose;
612 struct ref_dir packed;
ce40979c
MH
613 /* The submodule name, or "" for the main repo. */
614 char name[FLEX_ARRAY];
79c7ca54 615} *ref_cache;
0e88c130 616
760c4512 617static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 618{
1b7edaf9 619 if (refs->did_packed)
d3177275 620 clear_ref_dir(&refs->packed);
760c4512 621 refs->did_packed = 0;
5e290ff7 622}
e1e22e37 623
760c4512
MH
624static void clear_loose_ref_cache(struct ref_cache *refs)
625{
626 if (refs->did_loose)
d3177275 627 clear_ref_dir(&refs->loose);
760c4512
MH
628 refs->did_loose = 0;
629}
630
79c7ca54 631static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 632{
ce40979c 633 int len;
79c7ca54 634 struct ref_cache *refs;
ce40979c
MH
635 if (!submodule)
636 submodule = "";
637 len = strlen(submodule) + 1;
79c7ca54 638 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 639 memcpy(refs->name, submodule, len);
e5dbf605
MH
640 return refs;
641}
642
4349a668 643/*
79c7ca54 644 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
645 * the main repository, use submodule==NULL. The returned structure
646 * will be allocated and initialized but not necessarily populated; it
647 * should not be freed.
648 */
79c7ca54 649static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 650{
79c7ca54 651 struct ref_cache *refs = ref_cache;
0e88c130
MH
652 if (!submodule)
653 submodule = "";
654 while (refs) {
655 if (!strcmp(submodule, refs->name))
656 return refs;
657 refs = refs->next;
4349a668 658 }
0e88c130 659
79c7ca54
MH
660 refs = create_ref_cache(submodule);
661 refs->next = ref_cache;
662 ref_cache = refs;
0e88c130 663 return refs;
4349a668
MH
664}
665
8be8bde7 666void invalidate_ref_cache(const char *submodule)
f130b116 667{
c5f29abd
MH
668 struct ref_cache *refs = get_ref_cache(submodule);
669 clear_packed_ref_cache(refs);
670 clear_loose_ref_cache(refs);
5e290ff7 671}
e1e22e37 672
bc5fd6d3
MH
673/*
674 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
675 * Return a pointer to the refname within the line (null-terminated),
676 * or NULL if there was a problem.
677 */
678static const char *parse_ref_line(char *line, unsigned char *sha1)
679{
680 /*
681 * 42: the answer to everything.
682 *
683 * In this case, it happens to be the answer to
684 * 40 (length of sha1 hex representation)
685 * +1 (space in between hex and name)
686 * +1 (newline at the end of the line)
687 */
688 int len = strlen(line) - 42;
689
690 if (len <= 0)
691 return NULL;
692 if (get_sha1_hex(line, sha1) < 0)
693 return NULL;
694 if (!isspace(line[40]))
695 return NULL;
696 line += 41;
697 if (isspace(*line))
698 return NULL;
699 if (line[len] != '\n')
700 return NULL;
701 line[len] = 0;
702
703 return line;
704}
705
d3177275 706static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 707{
e9c4c111 708 struct ref_entry *last = NULL;
f4204ab9
JH
709 char refline[PATH_MAX];
710 int flag = REF_ISPACKED;
711
712 while (fgets(refline, sizeof(refline), f)) {
713 unsigned char sha1[20];
dfefa935 714 const char *refname;
f4204ab9
JH
715 static const char header[] = "# pack-refs with:";
716
717 if (!strncmp(refline, header, sizeof(header)-1)) {
718 const char *traits = refline + sizeof(header) - 1;
719 if (strstr(traits, " peeled "))
720 flag |= REF_KNOWS_PEELED;
721 /* perhaps other traits later as well */
722 continue;
723 }
724
dfefa935
MH
725 refname = parse_ref_line(refline, sha1);
726 if (refname) {
dd73ecd1 727 last = create_ref_entry(refname, sha1, flag, 1);
d3177275 728 add_ref(dir, last);
f4204ab9
JH
729 continue;
730 }
731 if (last &&
732 refline[0] == '^' &&
733 strlen(refline) == 42 &&
734 refline[41] == '\n' &&
735 !get_sha1_hex(refline + 1, sha1))
593f1bb8 736 hashcpy(last->u.value.peeled, sha1);
f4204ab9 737 }
f4204ab9
JH
738}
739
d3177275 740static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 741{
4349a668
MH
742 if (!refs->did_packed) {
743 const char *packed_refs_file;
744 FILE *f;
0bad611b 745
316b097a
MH
746 if (*refs->name)
747 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
748 else
749 packed_refs_file = git_path("packed-refs");
750 f = fopen(packed_refs_file, "r");
e1e22e37 751 if (f) {
2c5c66be 752 read_packed_refs(f, &refs->packed);
e1e22e37 753 fclose(f);
e1e22e37 754 }
0bad611b 755 refs->did_packed = 1;
e1e22e37 756 }
e9c4c111 757 return &refs->packed;
e1e22e37
LT
758}
759
30249ee6
MH
760void add_packed_ref(const char *refname, const unsigned char *sha1)
761{
762 add_ref(get_packed_refs(get_ref_cache(NULL)),
763 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
764}
765
abc39098
MH
766/*
767 * Read the loose references for refs from the namespace dirname.
9f2fb4a3
MH
768 * dirname must end with '/'. dir must be the directory entry
769 * corresponding to dirname.
abc39098 770 */
66a3d20b 771static void get_ref_dir(struct ref_cache *refs, const char *dirname,
d3177275 772 struct ref_dir *dir)
e1e22e37 773{
d3177275 774 DIR *d;
0bad611b 775 const char *path;
d5fdae67 776 struct dirent *de;
abc39098 777 int dirnamelen = strlen(dirname);
72b64b44 778 struct strbuf refname;
0bad611b 779
3b124823 780 if (*refs->name)
66a3d20b 781 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 782 else
66a3d20b 783 path = git_path("%s", dirname);
0bad611b 784
d3177275 785 d = opendir(path);
d5fdae67
MH
786 if (!d)
787 return;
788
66a3d20b
MH
789 strbuf_init(&refname, dirnamelen + 257);
790 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
791
792 while ((de = readdir(d)) != NULL) {
793 unsigned char sha1[20];
794 struct stat st;
795 int flag;
d5fdae67
MH
796 const char *refdir;
797
798 if (de->d_name[0] == '.')
799 continue;
d5fdae67
MH
800 if (has_extension(de->d_name, ".lock"))
801 continue;
72b64b44 802 strbuf_addstr(&refname, de->d_name);
d5fdae67 803 refdir = *refs->name
72b64b44
MH
804 ? git_path_submodule(refs->name, "%s", refname.buf)
805 : git_path("%s", refname.buf);
806 if (stat(refdir, &st) < 0) {
807 ; /* silently ignore */
808 } else if (S_ISDIR(st.st_mode)) {
abc39098 809 strbuf_addch(&refname, '/');
9f2fb4a3
MH
810 get_ref_dir(refs, refname.buf,
811 &search_for_subdir(dir, refname.buf, 1)->u.subdir);
72b64b44
MH
812 } else {
813 if (*refs->name) {
814 hashclr(sha1);
815 flag = 0;
816 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
817 hashclr(sha1);
818 flag |= REF_ISBROKEN;
819 }
820 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
821 hashclr(sha1);
822 flag |= REF_ISBROKEN;
823 }
9f2fb4a3
MH
824 add_entry_to_dir(dir,
825 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 826 }
66a3d20b 827 strbuf_setlen(&refname, dirnamelen);
e1e22e37 828 }
72b64b44 829 strbuf_release(&refname);
d5fdae67 830 closedir(d);
e1e22e37
LT
831}
832
d3177275 833static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 834{
4349a668 835 if (!refs->did_loose) {
9f2fb4a3
MH
836 get_ref_dir(refs, "refs/",
837 &search_for_subdir(&refs->loose, "refs/", 1)->u.subdir);
4349a668 838 refs->did_loose = 1;
e1e22e37 839 }
2c5c66be 840 return &refs->loose;
e1e22e37
LT
841}
842
ca8db142
LT
843/* We allow "recursive" symbolic refs. Only within reason, though */
844#define MAXDEPTH 5
0ebde32c
LT
845#define MAXREFLEN (1024)
846
e5fa45c1
JH
847/*
848 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
849 * from the loose refs in ref_cache refs. Find <refname> in the
850 * packed-refs file for the submodule.
e5fa45c1 851 */
b0626608 852static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 853 const char *refname, unsigned char *sha1)
0ebde32c 854{
2c5c66be 855 struct ref_entry *ref;
d3177275 856 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 857
432ad41e 858 ref = find_ref(dir, refname);
b0626608
MH
859 if (ref == NULL)
860 return -1;
861
593f1bb8 862 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 863 return 0;
0ebde32c
LT
864}
865
b0626608 866static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 867 const char *refname, unsigned char *sha1,
dfefa935 868 int recursion)
0ebde32c 869{
064d51dc 870 int fd, len;
0ebde32c 871 char buffer[128], *p;
064d51dc 872 char *path;
0ebde32c 873
064d51dc 874 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 875 return -1;
064d51dc
MH
876 path = *refs->name
877 ? git_path_submodule(refs->name, "%s", refname)
878 : git_path("%s", refname);
879 fd = open(path, O_RDONLY);
0ebde32c 880 if (fd < 0)
b0626608 881 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
882
883 len = read(fd, buffer, sizeof(buffer)-1);
884 close(fd);
885 if (len < 0)
886 return -1;
887 while (len && isspace(buffer[len-1]))
888 len--;
889 buffer[len] = 0;
890
891 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 892 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
893 return 0;
894
895 /* Symref? */
896 if (strncmp(buffer, "ref:", 4))
897 return -1;
898 p = buffer + 4;
899 while (isspace(*p))
900 p++;
901
064d51dc 902 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
903}
904
85be1fe3 905int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
906{
907 int len = strlen(path), retval;
064d51dc 908 char *submodule;
b0626608 909 struct ref_cache *refs;
0ebde32c
LT
910
911 while (len && path[len-1] == '/')
912 len--;
913 if (!len)
914 return -1;
b0626608
MH
915 submodule = xstrndup(path, len);
916 refs = get_ref_cache(submodule);
917 free(submodule);
918
064d51dc 919 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
920 return retval;
921}
ca8db142 922
4886b89f 923/*
c224ca7f
MH
924 * Try to read ref from the packed references. On success, set sha1
925 * and return 0; otherwise, return -1.
4886b89f 926 */
dfefa935 927static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 928{
d3177275 929 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 930 struct ref_entry *entry = find_ref(packed, refname);
2c5c66be 931 if (entry) {
593f1bb8 932 hashcpy(sha1, entry->u.value.sha1);
2c5c66be 933 return 0;
c224ca7f
MH
934 }
935 return -1;
936}
937
8d68493f 938const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 939{
0104ca09
HO
940 int depth = MAXDEPTH;
941 ssize_t len;
a876ed83 942 char buffer[256];
dfefa935 943 static char refname_buffer[256];
ca8db142 944
8da19775
JH
945 if (flag)
946 *flag = 0;
947
dfefa935 948 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
949 return NULL;
950
a876ed83 951 for (;;) {
55956350 952 char path[PATH_MAX];
a876ed83
JH
953 struct stat st;
954 char *buf;
955 int fd;
8a65ff76 956
a876ed83
JH
957 if (--depth < 0)
958 return NULL;
ca8db142 959
dfefa935 960 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 961
a876ed83 962 if (lstat(path, &st) < 0) {
c224ca7f
MH
963 if (errno != ENOENT)
964 return NULL;
965 /*
966 * The loose reference file does not exist;
967 * check for a packed reference.
968 */
dfefa935 969 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
970 if (flag)
971 *flag |= REF_ISPACKED;
dfefa935 972 return refname;
434cd0cd 973 }
c224ca7f
MH
974 /* The reference is not a packed reference, either. */
975 if (reading) {
a876ed83 976 return NULL;
c224ca7f
MH
977 } else {
978 hashclr(sha1);
dfefa935 979 return refname;
c224ca7f 980 }
a876ed83 981 }
ca8db142 982
a876ed83
JH
983 /* Follow "normalized" - ie "refs/.." symlinks by hand */
984 if (S_ISLNK(st.st_mode)) {
985 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
986 if (len < 0)
987 return NULL;
b54cb795 988 buffer[len] = 0;
1f58a038
MH
989 if (!prefixcmp(buffer, "refs/") &&
990 !check_refname_format(buffer, 0)) {
dfefa935
MH
991 strcpy(refname_buffer, buffer);
992 refname = refname_buffer;
8da19775
JH
993 if (flag)
994 *flag |= REF_ISSYMREF;
a876ed83
JH
995 continue;
996 }
ca8db142 997 }
a876ed83 998
7a21632f
DS
999 /* Is it a directory? */
1000 if (S_ISDIR(st.st_mode)) {
1001 errno = EISDIR;
1002 return NULL;
1003 }
1004
a876ed83
JH
1005 /*
1006 * Anything else, just open it and try to use it as
1007 * a ref
1008 */
1009 fd = open(path, O_RDONLY);
1010 if (fd < 0)
1011 return NULL;
93d26e4c 1012 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1013 close(fd);
28775050
MH
1014 if (len < 0)
1015 return NULL;
1016 while (len && isspace(buffer[len-1]))
1017 len--;
1018 buffer[len] = '\0';
a876ed83
JH
1019
1020 /*
1021 * Is it a symbolic ref?
1022 */
28775050 1023 if (prefixcmp(buffer, "ref:"))
a876ed83 1024 break;
55956350
JH
1025 if (flag)
1026 *flag |= REF_ISSYMREF;
a876ed83 1027 buf = buffer + 4;
28775050
MH
1028 while (isspace(*buf))
1029 buf++;
313fb010 1030 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1031 if (flag)
1032 *flag |= REF_ISBROKEN;
313fb010
MH
1033 return NULL;
1034 }
dfefa935 1035 refname = strcpy(refname_buffer, buf);
8a65ff76 1036 }
f989fea0
MH
1037 /* Please note that FETCH_HEAD has a second line containing other data. */
1038 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1039 if (flag)
1040 *flag |= REF_ISBROKEN;
a876ed83 1041 return NULL;
629cd3ac 1042 }
dfefa935 1043 return refname;
a876ed83
JH
1044}
1045
96ec7b1e
NTND
1046char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1047{
8cad4744 1048 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1049 return ret ? xstrdup(ret) : NULL;
1050}
1051
d08bae7e
IL
1052/* The argument to filter_refs */
1053struct ref_filter {
1054 const char *pattern;
1055 each_ref_fn *fn;
1056 void *cb_data;
1057};
1058
dfefa935 1059int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1060{
8d68493f 1061 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1062 return 0;
1063 return -1;
8a65ff76
LT
1064}
1065
dfefa935 1066int read_ref(const char *refname, unsigned char *sha1)
c6893323 1067{
dfefa935 1068 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1069}
1070
bc5fd6d3 1071int ref_exists(const char *refname)
ef06b918 1072{
bc5fd6d3
MH
1073 unsigned char sha1[20];
1074 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1075}
1076
85be1fe3 1077static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1078 void *data)
d08bae7e
IL
1079{
1080 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1081 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1082 return 0;
85be1fe3 1083 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1084}
1085
dfefa935 1086int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1087{
1088 int flag;
1089 unsigned char base[20];
1090 struct object *o;
1091
dfefa935
MH
1092 if (current_ref && (current_ref->name == refname
1093 || !strcmp(current_ref->name, refname))) {
0ae91be0 1094 if (current_ref->flag & REF_KNOWS_PEELED) {
593f1bb8 1095 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
1096 return 0;
1097 }
593f1bb8 1098 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
1099 goto fallback;
1100 }
1101
dfefa935 1102 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1103 return -1;
1104
1105 if ((flag & REF_ISPACKED)) {
d3177275 1106 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
432ad41e 1107 struct ref_entry *r = find_ref(dir, refname);
cf0adba7 1108
e9c4c111 1109 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
593f1bb8 1110 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1111 return 0;
cf0adba7 1112 }
cf0adba7
JH
1113 }
1114
0ae91be0 1115fallback:
cf0adba7 1116 o = parse_object(base);
8c87dc77 1117 if (o && o->type == OBJ_TAG) {
dfefa935 1118 o = deref_tag(o, refname, 0);
cf0adba7
JH
1119 if (o) {
1120 hashcpy(sha1, o->sha1);
1121 return 0;
1122 }
1123 }
1124 return -1;
1125}
1126
bc5fd6d3
MH
1127struct warn_if_dangling_data {
1128 FILE *fp;
1129 const char *refname;
1130 const char *msg_fmt;
1131};
1132
1133static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1134 int flags, void *cb_data)
1135{
1136 struct warn_if_dangling_data *d = cb_data;
1137 const char *resolves_to;
1138 unsigned char junk[20];
1139
1140 if (!(flags & REF_ISSYMREF))
1141 return 0;
1142
1143 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1144 if (!resolves_to || strcmp(resolves_to, d->refname))
1145 return 0;
1146
1147 fprintf(d->fp, d->msg_fmt, refname);
1148 return 0;
1149}
1150
1151void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1152{
1153 struct warn_if_dangling_data data;
1154
1155 data.fp = fp;
1156 data.refname = refname;
1157 data.msg_fmt = msg_fmt;
1158 for_each_rawref(warn_if_dangling_symref, &data);
1159}
1160
0bad611b
HV
1161static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1162 int trim, int flags, void *cb_data)
8a65ff76 1163{
316b097a 1164 struct ref_cache *refs = get_ref_cache(submodule);
933ac036
MH
1165 struct ref_dir *packed_dir = get_packed_refs(refs);
1166 struct ref_dir *loose_dir = get_loose_refs(refs);
1167 int retval = 0;
1168
1169 if (base && *base) {
1170 packed_dir = find_containing_dir(packed_dir, base, 0);
1171 loose_dir = find_containing_dir(loose_dir, base, 0);
1172 }
1173
1174 if (packed_dir && loose_dir) {
1175 sort_ref_dir(packed_dir);
1176 sort_ref_dir(loose_dir);
1177 retval = do_for_each_ref_in_dirs(
1178 packed_dir, loose_dir,
1179 base, fn, trim, flags, cb_data);
1180 } else if (packed_dir) {
1181 sort_ref_dir(packed_dir);
1182 retval = do_for_each_ref_in_dir(
1183 packed_dir, 0,
1184 base, fn, trim, flags, cb_data);
1185 } else if (loose_dir) {
1186 sort_ref_dir(loose_dir);
1187 retval = do_for_each_ref_in_dir(
1188 loose_dir, 0,
1189 base, fn, trim, flags, cb_data);
1190 }
1191
1192 return retval;
8a65ff76
LT
1193}
1194
0bad611b 1195static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1196{
1197 unsigned char sha1[20];
8da19775
JH
1198 int flag;
1199
0bad611b
HV
1200 if (submodule) {
1201 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1202 return fn("HEAD", sha1, 0, cb_data);
1203
1204 return 0;
1205 }
1206
c6893323 1207 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1208 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1209
2f34ba32 1210 return 0;
723c31fe
LT
1211}
1212
0bad611b
HV
1213int head_ref(each_ref_fn fn, void *cb_data)
1214{
1215 return do_head_ref(NULL, fn, cb_data);
1216}
1217
9ef6aeb0
HV
1218int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1219{
1220 return do_head_ref(submodule, fn, cb_data);
1221}
1222
cb5d709f 1223int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1224{
b3cfc406 1225 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1226}
1227
9ef6aeb0
HV
1228int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1229{
b3cfc406 1230 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1231}
1232
2a8177b6
CC
1233int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1234{
0bad611b 1235 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1236}
1237
9ef6aeb0
HV
1238int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1239 each_ref_fn fn, void *cb_data)
1240{
1241 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1242}
1243
cb5d709f 1244int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1245{
2a8177b6 1246 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1247}
1248
9ef6aeb0
HV
1249int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1250{
1251 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1252}
1253
cb5d709f 1254int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1255{
2a8177b6 1256 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1257}
1258
9ef6aeb0
HV
1259int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1260{
1261 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1262}
1263
cb5d709f 1264int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1265{
2a8177b6 1266 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1267}
1268
9ef6aeb0
HV
1269int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1270{
1271 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1272}
1273
29268700
CC
1274int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1275{
0bad611b 1276 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1277}
1278
a1bea2c1
JT
1279int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1280{
1281 struct strbuf buf = STRBUF_INIT;
1282 int ret = 0;
1283 unsigned char sha1[20];
1284 int flag;
1285
1286 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1287 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1288 ret = fn(buf.buf, sha1, flag, cb_data);
1289 strbuf_release(&buf);
1290
1291 return ret;
1292}
1293
1294int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1295{
1296 struct strbuf buf = STRBUF_INIT;
1297 int ret;
1298 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1299 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1300 strbuf_release(&buf);
1301 return ret;
1302}
1303
b09fe971
IL
1304int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1305 const char *prefix, void *cb_data)
d08bae7e
IL
1306{
1307 struct strbuf real_pattern = STRBUF_INIT;
1308 struct ref_filter filter;
d08bae7e
IL
1309 int ret;
1310
b09fe971 1311 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1312 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1313 else if (prefix)
1314 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1315 strbuf_addstr(&real_pattern, pattern);
1316
894a9d33 1317 if (!has_glob_specials(pattern)) {
9517e6b8 1318 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1319 if (real_pattern.buf[real_pattern.len - 1] != '/')
1320 strbuf_addch(&real_pattern, '/');
1321 /* No need to check for '*', there is none. */
1322 strbuf_addch(&real_pattern, '*');
1323 }
1324
1325 filter.pattern = real_pattern.buf;
1326 filter.fn = fn;
1327 filter.cb_data = cb_data;
1328 ret = for_each_ref(filter_refs, &filter);
1329
1330 strbuf_release(&real_pattern);
1331 return ret;
1332}
1333
b09fe971
IL
1334int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1335{
1336 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1337}
1338
f8948e2f
JH
1339int for_each_rawref(each_ref_fn fn, void *cb_data)
1340{
b3cfc406 1341 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1342 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1343}
1344
4577e483 1345const char *prettify_refname(const char *name)
a9c37a72 1346{
a9c37a72
DB
1347 return name + (
1348 !prefixcmp(name, "refs/heads/") ? 11 :
1349 !prefixcmp(name, "refs/tags/") ? 10 :
1350 !prefixcmp(name, "refs/remotes/") ? 13 :
1351 0);
1352}
1353
79803322
SP
1354const char *ref_rev_parse_rules[] = {
1355 "%.*s",
1356 "refs/%.*s",
1357 "refs/tags/%.*s",
1358 "refs/heads/%.*s",
1359 "refs/remotes/%.*s",
1360 "refs/remotes/%.*s/HEAD",
1361 NULL
1362};
1363
1364int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1365{
1366 const char **p;
1367 const int abbrev_name_len = strlen(abbrev_name);
1368
1369 for (p = rules; *p; p++) {
1370 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1371 return 1;
1372 }
1373 }
1374
1375 return 0;
1376}
1377
e5f38ec3 1378static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1379 const unsigned char *old_sha1, int mustexist)
1380{
c6893323 1381 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1382 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1383 unlock_ref(lock);
1384 return NULL;
1385 }
a89fccd2 1386 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1387 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1388 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1389 unlock_ref(lock);
1390 return NULL;
1391 }
1392 return lock;
1393}
1394
7155b727 1395static int remove_empty_directories(const char *file)
bc7127ef
JH
1396{
1397 /* we want to create a file but there is a directory there;
1398 * if that is an empty directory (or a directory that contains
1399 * only empty directories), remove them.
1400 */
7155b727
JS
1401 struct strbuf path;
1402 int result;
bc7127ef 1403
7155b727
JS
1404 strbuf_init(&path, 20);
1405 strbuf_addstr(&path, file);
1406
a0f4afbe 1407 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1408
1409 strbuf_release(&path);
1410
1411 return result;
bc7127ef
JH
1412}
1413
ff74f7f1
JH
1414/*
1415 * *string and *len will only be substituted, and *string returned (for
1416 * later free()ing) if the string passed in is a magic short-hand form
1417 * to name a branch.
1418 */
1419static char *substitute_branch_name(const char **string, int *len)
1420{
1421 struct strbuf buf = STRBUF_INIT;
1422 int ret = interpret_branch_name(*string, &buf);
1423
1424 if (ret == *len) {
1425 size_t size;
1426 *string = strbuf_detach(&buf, &size);
1427 *len = size;
1428 return (char *)*string;
1429 }
1430
1431 return NULL;
1432}
1433
1434int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1435{
1436 char *last_branch = substitute_branch_name(&str, &len);
1437 const char **p, *r;
1438 int refs_found = 0;
1439
1440 *ref = NULL;
1441 for (p = ref_rev_parse_rules; *p; p++) {
1442 char fullref[PATH_MAX];
1443 unsigned char sha1_from_ref[20];
1444 unsigned char *this_result;
1445 int flag;
1446
1447 this_result = refs_found ? sha1_from_ref : sha1;
1448 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1449 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1450 if (r) {
1451 if (!refs_found++)
1452 *ref = xstrdup(r);
1453 if (!warn_ambiguous_refs)
1454 break;
55956350 1455 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1456 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1457 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1458 warning("ignoring broken ref %s.", fullref);
1459 }
ff74f7f1
JH
1460 }
1461 free(last_branch);
1462 return refs_found;
1463}
1464
1465int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1466{
1467 char *last_branch = substitute_branch_name(&str, &len);
1468 const char **p;
1469 int logs_found = 0;
1470
1471 *log = NULL;
1472 for (p = ref_rev_parse_rules; *p; p++) {
1473 struct stat st;
1474 unsigned char hash[20];
1475 char path[PATH_MAX];
1476 const char *ref, *it;
1477
1478 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1479 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1480 if (!ref)
1481 continue;
1482 if (!stat(git_path("logs/%s", path), &st) &&
1483 S_ISREG(st.st_mode))
1484 it = path;
1485 else if (strcmp(ref, path) &&
1486 !stat(git_path("logs/%s", ref), &st) &&
1487 S_ISREG(st.st_mode))
1488 it = ref;
1489 else
1490 continue;
1491 if (!logs_found++) {
1492 *log = xstrdup(it);
1493 hashcpy(sha1, hash);
1494 }
1495 if (!warn_ambiguous_refs)
1496 break;
1497 }
1498 free(last_branch);
1499 return logs_found;
1500}
1501
dfefa935
MH
1502static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1503 const unsigned char *old_sha1,
1504 int flags, int *type_p)
4bd18c43 1505{
434cd0cd 1506 char *ref_file;
dfefa935 1507 const char *orig_refname = refname;
4bd18c43 1508 struct ref_lock *lock;
5cc3cef9 1509 int last_errno = 0;
acd3b9ec 1510 int type, lflags;
4431fcc4 1511 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1512 int missing = 0;
4bd18c43
SP
1513
1514 lock = xcalloc(1, sizeof(struct ref_lock));
1515 lock->lock_fd = -1;
1516
8d68493f 1517 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1518 if (!refname && errno == EISDIR) {
bc7127ef
JH
1519 /* we are trying to lock foo but we used to
1520 * have foo/bar which now does not exist;
1521 * it is normal for the empty directory 'foo'
1522 * to remain.
1523 */
dfefa935 1524 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1525 if (remove_empty_directories(ref_file)) {
1526 last_errno = errno;
dfefa935 1527 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1528 goto error_return;
1529 }
8d68493f 1530 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1531 }
68db31cc
SV
1532 if (type_p)
1533 *type_p = type;
dfefa935 1534 if (!refname) {
5cc3cef9 1535 last_errno = errno;
818f477c 1536 error("unable to resolve reference %s: %s",
dfefa935 1537 orig_refname, strerror(errno));
5cc3cef9 1538 goto error_return;
4bd18c43 1539 }
5bdd8d4a 1540 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1541 /* When the ref did not exist and we are creating it,
1542 * make sure there is no existing ref that is packed
1543 * whose name begins with our refname, nor a ref whose
1544 * name is a proper prefix of our refname.
1545 */
5bdd8d4a 1546 if (missing &&
316b097a 1547 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1548 last_errno = ENOTDIR;
c976d415 1549 goto error_return;
f475e08e 1550 }
22a3844e 1551
c33d5174 1552 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1553
acd3b9ec
JH
1554 lflags = LOCK_DIE_ON_ERROR;
1555 if (flags & REF_NODEREF) {
dfefa935 1556 refname = orig_refname;
acd3b9ec
JH
1557 lflags |= LOCK_NODEREF;
1558 }
dfefa935
MH
1559 lock->ref_name = xstrdup(refname);
1560 lock->orig_ref_name = xstrdup(orig_refname);
1561 ref_file = git_path("%s", refname);
5bdd8d4a 1562 if (missing)
68db31cc
SV
1563 lock->force_write = 1;
1564 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1565 lock->force_write = 1;
4bd18c43 1566
5cc3cef9
JH
1567 if (safe_create_leading_directories(ref_file)) {
1568 last_errno = errno;
1569 error("unable to create directory for %s", ref_file);
1570 goto error_return;
1571 }
4bd18c43 1572
acd3b9ec 1573 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1574 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1575
1576 error_return:
1577 unlock_ref(lock);
1578 errno = last_errno;
1579 return NULL;
4bd18c43
SP
1580}
1581
dfefa935 1582struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1583{
53cce84c 1584 char refpath[PATH_MAX];
dfefa935 1585 if (check_refname_format(refname, 0))
4bd18c43 1586 return NULL;
dfefa935 1587 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1588 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1589}
1590
dfefa935
MH
1591struct ref_lock *lock_any_ref_for_update(const char *refname,
1592 const unsigned char *old_sha1, int flags)
4bd18c43 1593{
dfefa935 1594 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1595 return NULL;
dfefa935 1596 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1597}
1598
d66da478
MH
1599struct repack_without_ref_sb {
1600 const char *refname;
1601 int fd;
1602};
1603
1604static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1605 int flags, void *cb_data)
1606{
1607 struct repack_without_ref_sb *data = cb_data;
1608 char line[PATH_MAX + 100];
1609 int len;
1610
1611 if (!strcmp(data->refname, refname))
1612 return 0;
1613 len = snprintf(line, sizeof(line), "%s %s\n",
1614 sha1_to_hex(sha1), refname);
1615 /* this should not happen but just being defensive */
1616 if (len > sizeof(line))
1617 die("too long a refname '%s'", refname);
1618 write_or_die(data->fd, line, len);
1619 return 0;
1620}
1621
26a063a1
JH
1622static struct lock_file packlock;
1623
c0277d15
JH
1624static int repack_without_ref(const char *refname)
1625{
d66da478 1626 struct repack_without_ref_sb data;
d3177275 1627 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 1628 if (find_ref(packed, refname) == NULL)
c0277d15 1629 return 0;
d66da478
MH
1630 data.refname = refname;
1631 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1632 if (data.fd < 0) {
1b018fd9 1633 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1634 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1635 }
d3177275 1636 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1637 return commit_lock_file(&packlock);
1638}
1639
eca35a25 1640int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1641{
1642 struct ref_lock *lock;
eca35a25 1643 int err, i = 0, ret = 0, flag = 0;
c0277d15 1644
68db31cc 1645 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1646 if (!lock)
1647 return 1;
045a476f 1648 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1649 /* loose */
eca35a25
MV
1650 const char *path;
1651
1652 if (!(delopt & REF_NODEREF)) {
1653 i = strlen(lock->lk->filename) - 5; /* .lock */
1654 lock->lk->filename[i] = 0;
1655 path = lock->lk->filename;
1656 } else {
9db56f71 1657 path = git_path("%s", refname);
eca35a25 1658 }
691f1a28
AR
1659 err = unlink_or_warn(path);
1660 if (err && errno != ENOENT)
c0277d15 1661 ret = 1;
691f1a28 1662
eca35a25
MV
1663 if (!(delopt & REF_NODEREF))
1664 lock->lk->filename[i] = '.';
c0277d15
JH
1665 }
1666 /* removing the loose one could have resurrected an earlier
1667 * packed one. Also, if it was not loose we need to repack
1668 * without it.
1669 */
1670 ret |= repack_without_ref(refname);
1671
691f1a28 1672 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1673 invalidate_ref_cache(NULL);
c0277d15
JH
1674 unlock_ref(lock);
1675 return ret;
4bd18c43
SP
1676}
1677
765c2258
PH
1678/*
1679 * People using contrib's git-new-workdir have .git/logs/refs ->
1680 * /some/other/path/.git/logs/refs, and that may live on another device.
1681 *
1682 * IOW, to avoid cross device rename errors, the temporary renamed log must
1683 * live into logs/refs.
1684 */
1685#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1686
dfefa935 1687int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1688{
c976d415
LH
1689 unsigned char sha1[20], orig_sha1[20];
1690 int flag = 0, logmoved = 0;
1691 struct ref_lock *lock;
c976d415 1692 struct stat loginfo;
dfefa935 1693 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1694 const char *symref = NULL;
316b097a 1695 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1696
450d4c0f 1697 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1698 return error("reflog for %s is a symlink", oldrefname);
c976d415 1699
8d68493f 1700 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1701 if (flag & REF_ISSYMREF)
fa58186c 1702 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1703 oldrefname);
eca35a25 1704 if (!symref)
dfefa935 1705 return error("refname %s not found", oldrefname);
c976d415 1706
316b097a 1707 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1708 return 1;
1709
316b097a 1710 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1711 return 1;
1712
dfefa935 1713 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1714 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1715 oldrefname, strerror(errno));
c976d415 1716
dfefa935
MH
1717 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1718 error("unable to delete old %s", oldrefname);
c976d415
LH
1719 goto rollback;
1720 }
1721
dfefa935
MH
1722 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1723 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1724 if (errno==EISDIR) {
dfefa935
MH
1725 if (remove_empty_directories(git_path("%s", newrefname))) {
1726 error("Directory not empty: %s", newrefname);
c976d415
LH
1727 goto rollback;
1728 }
1729 } else {
dfefa935 1730 error("unable to delete existing %s", newrefname);
c976d415
LH
1731 goto rollback;
1732 }
1733 }
1734
dfefa935
MH
1735 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1736 error("unable to create directory for %s", newrefname);
c976d415
LH
1737 goto rollback;
1738 }
1739
1740 retry:
dfefa935 1741 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1742 if (errno==EISDIR || errno==ENOTDIR) {
1743 /*
1744 * rename(a, b) when b is an existing
1745 * directory ought to result in ISDIR, but
1746 * Solaris 5.8 gives ENOTDIR. Sheesh.
1747 */
dfefa935
MH
1748 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1749 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1750 goto rollback;
1751 }
1752 goto retry;
1753 } else {
765c2258 1754 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1755 newrefname, strerror(errno));
c976d415
LH
1756 goto rollback;
1757 }
1758 }
1759 logmoved = log;
1760
dfefa935 1761 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1762 if (!lock) {
dfefa935 1763 error("unable to lock %s for update", newrefname);
c976d415
LH
1764 goto rollback;
1765 }
c976d415
LH
1766 lock->force_write = 1;
1767 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1768 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1769 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1770 goto rollback;
1771 }
1772
1773 return 0;
1774
1775 rollback:
dfefa935 1776 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1777 if (!lock) {
dfefa935 1778 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1779 goto rollbacklog;
1780 }
1781
1782 lock->force_write = 1;
1783 flag = log_all_ref_updates;
1784 log_all_ref_updates = 0;
1785 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1786 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1787 log_all_ref_updates = flag;
1788
1789 rollbacklog:
dfefa935 1790 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1791 error("unable to restore logfile %s from %s: %s",
dfefa935 1792 oldrefname, newrefname, strerror(errno));
c976d415 1793 if (!logmoved && log &&
dfefa935 1794 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1795 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1796 oldrefname, strerror(errno));
c976d415
LH
1797
1798 return 1;
1799}
1800
435fc852 1801int close_ref(struct ref_lock *lock)
b531394d
BC
1802{
1803 if (close_lock_file(lock->lk))
1804 return -1;
1805 lock->lock_fd = -1;
1806 return 0;
1807}
1808
435fc852 1809int commit_ref(struct ref_lock *lock)
b531394d
BC
1810{
1811 if (commit_lock_file(lock->lk))
1812 return -1;
1813 lock->lock_fd = -1;
1814 return 0;
1815}
1816
e5f38ec3 1817void unlock_ref(struct ref_lock *lock)
4bd18c43 1818{
4ed7cd3a
BC
1819 /* Do not free lock->lk -- atexit() still looks at them */
1820 if (lock->lk)
1821 rollback_lock_file(lock->lk);
434cd0cd 1822 free(lock->ref_name);
1655707c 1823 free(lock->orig_ref_name);
4bd18c43
SP
1824 free(lock);
1825}
1826
0ec29a47
JH
1827/*
1828 * copy the reflog message msg to buf, which has been allocated sufficiently
1829 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1830 * because reflog file is one line per entry.
1831 */
1832static int copy_msg(char *buf, const char *msg)
1833{
1834 char *cp = buf;
1835 char c;
1836 int wasspace = 1;
1837
1838 *cp++ = '\t';
1839 while ((c = *msg++)) {
1840 if (wasspace && isspace(c))
1841 continue;
1842 wasspace = isspace(c);
1843 if (wasspace)
1844 c = ' ';
1845 *cp++ = c;
1846 }
1847 while (buf < cp && isspace(cp[-1]))
1848 cp--;
1849 *cp++ = '\n';
1850 return cp - buf;
1851}
1852
dfefa935 1853int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 1854{
859c3017 1855 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1856
dfefa935 1857 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 1858 if (log_all_ref_updates &&
dfefa935
MH
1859 (!prefixcmp(refname, "refs/heads/") ||
1860 !prefixcmp(refname, "refs/remotes/") ||
1861 !prefixcmp(refname, "refs/notes/") ||
1862 !strcmp(refname, "HEAD"))) {
157aaea5 1863 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1864 return error("unable to create directory for %s",
157aaea5 1865 logfile);
6de08ae6
SP
1866 oflags |= O_CREAT;
1867 }
1868
157aaea5 1869 logfd = open(logfile, oflags, 0666);
6de08ae6 1870 if (logfd < 0) {
1974bf62 1871 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1872 return 0;
3b463c3f
JH
1873
1874 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1875 if (remove_empty_directories(logfile)) {
3b463c3f 1876 return error("There are still logs under '%s'",
157aaea5 1877 logfile);
3b463c3f 1878 }
157aaea5 1879 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1880 }
1881
1882 if (logfd < 0)
1883 return error("Unable to append to %s: %s",
157aaea5 1884 logfile, strerror(errno));
6de08ae6
SP
1885 }
1886
157aaea5 1887 adjust_shared_perm(logfile);
859c3017
EM
1888 close(logfd);
1889 return 0;
1890}
443b92b6 1891
dfefa935 1892static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
1893 const unsigned char *new_sha1, const char *msg)
1894{
1895 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1896 unsigned maxlen, len;
1897 int msglen;
157aaea5 1898 char log_file[PATH_MAX];
859c3017
EM
1899 char *logrec;
1900 const char *committer;
1901
1902 if (log_all_ref_updates < 0)
1903 log_all_ref_updates = !is_bare_repository();
1904
dfefa935 1905 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
1906 if (result)
1907 return result;
1908
1909 logfd = open(log_file, oflags);
1910 if (logfd < 0)
1911 return 0;
0ec29a47 1912 msglen = msg ? strlen(msg) : 0;
774751a8 1913 committer = git_committer_info(0);
8ac65937
JH
1914 maxlen = strlen(committer) + msglen + 100;
1915 logrec = xmalloc(maxlen);
1916 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1917 sha1_to_hex(old_sha1),
1918 sha1_to_hex(new_sha1),
8ac65937
JH
1919 committer);
1920 if (msglen)
0ec29a47 1921 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1922 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1923 free(logrec);
91c8d590 1924 if (close(logfd) != 0 || written != len)
9a13f0b7 1925 return error("Unable to append to %s", log_file);
6de08ae6
SP
1926 return 0;
1927}
1928
c3b0dec5
LT
1929static int is_branch(const char *refname)
1930{
1931 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1932}
1933
4bd18c43
SP
1934int write_ref_sha1(struct ref_lock *lock,
1935 const unsigned char *sha1, const char *logmsg)
1936{
1937 static char term = '\n';
c3b0dec5 1938 struct object *o;
4bd18c43
SP
1939
1940 if (!lock)
95fc7512 1941 return -1;
a89fccd2 1942 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1943 unlock_ref(lock);
1944 return 0;
95fc7512 1945 }
c3b0dec5
LT
1946 o = parse_object(sha1);
1947 if (!o) {
7be8b3ba 1948 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
1949 lock->ref_name, sha1_to_hex(sha1));
1950 unlock_ref(lock);
1951 return -1;
1952 }
1953 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1954 error("Trying to write non-commit object %s to branch %s",
1955 sha1_to_hex(sha1), lock->ref_name);
1956 unlock_ref(lock);
1957 return -1;
1958 }
93822c22
AW
1959 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1960 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1961 || close_ref(lock) < 0) {
c33d5174 1962 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1963 unlock_ref(lock);
1964 return -1;
1965 }
8bf90dc9 1966 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
1967 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1968 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1969 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1970 unlock_ref(lock);
1971 return -1;
1972 }
605fac8b
NP
1973 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1974 /*
1975 * Special hack: If a branch is updated directly and HEAD
1976 * points to it (may happen on the remote side of a push
1977 * for example) then logically the HEAD reflog should be
1978 * updated too.
1979 * A generic solution implies reverse symref information,
1980 * but finding all symrefs pointing to the given branch
1981 * would be rather costly for this rare event (the direct
1982 * update of a branch) to be worth it. So let's cheat and
1983 * check with HEAD only which should cover 99% of all usage
1984 * scenarios (even 100% of the default ones).
1985 */
1986 unsigned char head_sha1[20];
1987 int head_flag;
1988 const char *head_ref;
8cad4744 1989 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
1990 if (head_ref && (head_flag & REF_ISSYMREF) &&
1991 !strcmp(head_ref, lock->ref_name))
1992 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1993 }
b531394d 1994 if (commit_ref(lock)) {
434cd0cd 1995 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1996 unlock_ref(lock);
1997 return -1;
1998 }
4bd18c43
SP
1999 unlock_ref(lock);
2000 return 0;
95fc7512 2001}
d556fae2 2002
8b5157e4
NP
2003int create_symref(const char *ref_target, const char *refs_heads_master,
2004 const char *logmsg)
41b625b0
NP
2005{
2006 const char *lockpath;
2007 char ref[1000];
2008 int fd, len, written;
a4f34cbb 2009 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2010 unsigned char old_sha1[20], new_sha1[20];
2011
2012 if (logmsg && read_ref(ref_target, old_sha1))
2013 hashclr(old_sha1);
41b625b0 2014
d48744d1
JH
2015 if (safe_create_leading_directories(git_HEAD) < 0)
2016 return error("unable to create directory for %s", git_HEAD);
2017
41b625b0
NP
2018#ifndef NO_SYMLINK_HEAD
2019 if (prefer_symlink_refs) {
2020 unlink(git_HEAD);
2021 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2022 goto done;
41b625b0
NP
2023 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2024 }
2025#endif
2026
2027 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2028 if (sizeof(ref) <= len) {
2029 error("refname too long: %s", refs_heads_master);
47fc52e2 2030 goto error_free_return;
41b625b0
NP
2031 }
2032 lockpath = mkpath("%s.lock", git_HEAD);
2033 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2034 if (fd < 0) {
2035 error("Unable to open %s for writing", lockpath);
47fc52e2 2036 goto error_free_return;
41b625b0
NP
2037 }
2038 written = write_in_full(fd, ref, len);
91c8d590 2039 if (close(fd) != 0 || written != len) {
41b625b0 2040 error("Unable to write to %s", lockpath);
47fc52e2 2041 goto error_unlink_return;
41b625b0
NP
2042 }
2043 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2044 error("Unable to create %s", git_HEAD);
47fc52e2 2045 goto error_unlink_return;
41b625b0
NP
2046 }
2047 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2048 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2049 error_unlink_return:
691f1a28 2050 unlink_or_warn(lockpath);
47fc52e2
JH
2051 error_free_return:
2052 free(git_HEAD);
2053 return -1;
41b625b0 2054 }
8b5157e4 2055
ee96d11b 2056#ifndef NO_SYMLINK_HEAD
8b5157e4 2057 done:
ee96d11b 2058#endif
8b5157e4
NP
2059 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2060 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2061
47fc52e2 2062 free(git_HEAD);
41b625b0
NP
2063 return 0;
2064}
2065
16d7cc90
JH
2066static char *ref_msg(const char *line, const char *endp)
2067{
2068 const char *ep;
16d7cc90 2069 line += 82;
182af834
PH
2070 ep = memchr(line, '\n', endp - line);
2071 if (!ep)
2072 ep = endp;
2073 return xmemdupz(line, ep - line);
16d7cc90
JH
2074}
2075
dfefa935
MH
2076int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2077 unsigned char *sha1, char **msg,
2078 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2079{
e5229042 2080 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2081 char *tz_c;
e29cb53a 2082 int logfd, tz, reccnt = 0;
d556fae2
SP
2083 struct stat st;
2084 unsigned long date;
e5229042 2085 unsigned char logged_sha1[20];
cb48cb58 2086 void *log_mapped;
dc49cd76 2087 size_t mapsz;
d556fae2 2088
dfefa935 2089 logfile = git_path("logs/%s", refname);
d556fae2
SP
2090 logfd = open(logfile, O_RDONLY, 0);
2091 if (logfd < 0)
d824cbba 2092 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2093 fstat(logfd, &st);
2094 if (!st.st_size)
2095 die("Log %s is empty.", logfile);
dc49cd76
SP
2096 mapsz = xsize_t(st.st_size);
2097 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2098 logdata = log_mapped;
d556fae2
SP
2099 close(logfd);
2100
e5229042 2101 lastrec = NULL;
d556fae2
SP
2102 rec = logend = logdata + st.st_size;
2103 while (logdata < rec) {
e29cb53a 2104 reccnt++;
d556fae2
SP
2105 if (logdata < rec && *(rec-1) == '\n')
2106 rec--;
e5229042
SP
2107 lastgt = NULL;
2108 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2109 rec--;
e5229042
SP
2110 if (*rec == '>')
2111 lastgt = rec;
2112 }
2113 if (!lastgt)
d556fae2 2114 die("Log %s is corrupt.", logfile);
e5229042 2115 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2116 if (date <= at_time || cnt == 0) {
76a44c5c 2117 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2118 if (msg)
2119 *msg = ref_msg(rec, logend);
2120 if (cutoff_time)
2121 *cutoff_time = date;
2122 if (cutoff_tz)
2123 *cutoff_tz = tz;
2124 if (cutoff_cnt)
76a44c5c 2125 *cutoff_cnt = reccnt - 1;
e5229042
SP
2126 if (lastrec) {
2127 if (get_sha1_hex(lastrec, logged_sha1))
2128 die("Log %s is corrupt.", logfile);
2129 if (get_sha1_hex(rec + 41, sha1))
2130 die("Log %s is corrupt.", logfile);
a89fccd2 2131 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2132 warning("Log %s has gap after %s.",
73013afd 2133 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2134 }
e5f38ec3
JH
2135 }
2136 else if (date == at_time) {
e5229042
SP
2137 if (get_sha1_hex(rec + 41, sha1))
2138 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2139 }
2140 else {
e5229042
SP
2141 if (get_sha1_hex(rec + 41, logged_sha1))
2142 die("Log %s is corrupt.", logfile);
a89fccd2 2143 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2144 warning("Log %s unexpectedly ended on %s.",
73013afd 2145 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2146 }
2147 }
dc49cd76 2148 munmap(log_mapped, mapsz);
d556fae2
SP
2149 return 0;
2150 }
e5229042 2151 lastrec = rec;
ab2a1a32
JH
2152 if (cnt > 0)
2153 cnt--;
d556fae2
SP
2154 }
2155
e5229042
SP
2156 rec = logdata;
2157 while (rec < logend && *rec != '>' && *rec != '\n')
2158 rec++;
2159 if (rec == logend || *rec == '\n')
d556fae2 2160 die("Log %s is corrupt.", logfile);
e5229042 2161 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2162 tz = strtoul(tz_c, NULL, 10);
2163 if (get_sha1_hex(logdata, sha1))
2164 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2165 if (is_null_sha1(sha1)) {
2166 if (get_sha1_hex(logdata + 41, sha1))
2167 die("Log %s is corrupt.", logfile);
2168 }
16d7cc90
JH
2169 if (msg)
2170 *msg = ref_msg(logdata, logend);
dc49cd76 2171 munmap(log_mapped, mapsz);
16d7cc90
JH
2172
2173 if (cutoff_time)
2174 *cutoff_time = date;
2175 if (cutoff_tz)
2176 *cutoff_tz = tz;
2177 if (cutoff_cnt)
2178 *cutoff_cnt = reccnt;
2179 return 1;
d556fae2 2180}
2ff81662 2181
dfefa935 2182int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
2183{
2184 const char *logfile;
2185 FILE *logfp;
8ca78803 2186 struct strbuf sb = STRBUF_INIT;
2266bf27 2187 int ret = 0;
2ff81662 2188
dfefa935 2189 logfile = git_path("logs/%s", refname);
2ff81662
JH
2190 logfp = fopen(logfile, "r");
2191 if (!logfp)
883d60fa 2192 return -1;
101d15e0
JH
2193
2194 if (ofs) {
2195 struct stat statbuf;
2196 if (fstat(fileno(logfp), &statbuf) ||
2197 statbuf.st_size < ofs ||
2198 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 2199 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 2200 fclose(logfp);
8ca78803 2201 strbuf_release(&sb);
101d15e0 2202 return -1;
9d33f7c2 2203 }
101d15e0
JH
2204 }
2205
8ca78803 2206 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 2207 unsigned char osha1[20], nsha1[20];
883d60fa
JS
2208 char *email_end, *message;
2209 unsigned long timestamp;
8ca78803 2210 int tz;
2ff81662
JH
2211
2212 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
2213 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2214 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2215 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2216 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
2217 email_end[1] != ' ' ||
2218 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2219 !message || message[0] != ' ' ||
2220 (message[1] != '+' && message[1] != '-') ||
2221 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2222 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2223 continue; /* corrupt? */
883d60fa
JS
2224 email_end[1] = '\0';
2225 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2226 if (message[6] != '\t')
2227 message += 6;
2228 else
2229 message += 7;
8ca78803
RS
2230 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2231 cb_data);
883d60fa 2232 if (ret)
2266bf27 2233 break;
2ff81662
JH
2234 }
2235 fclose(logfp);
8ca78803 2236 strbuf_release(&sb);
2266bf27 2237 return ret;
2ff81662 2238}
e29cb53a 2239
dfefa935 2240int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2241{
dfefa935 2242 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2243}
2244
eb8381c8
NP
2245static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
2246{
d3177275 2247 DIR *d = opendir(git_path("logs/%s", base));
fcee5a14 2248 int retval = 0;
93c603fc
MH
2249 struct dirent *de;
2250 int baselen;
2251 char *log;
eb8381c8 2252
93c603fc
MH
2253 if (!d)
2254 return *base ? errno : 0;
eb8381c8 2255
93c603fc
MH
2256 baselen = strlen(base);
2257 log = xmalloc(baselen + 257);
2258 memcpy(log, base, baselen);
2259 if (baselen && base[baselen-1] != '/')
2260 log[baselen++] = '/';
eb8381c8 2261
93c603fc
MH
2262 while ((de = readdir(d)) != NULL) {
2263 struct stat st;
2264 int namelen;
eb8381c8 2265
93c603fc
MH
2266 if (de->d_name[0] == '.')
2267 continue;
2268 namelen = strlen(de->d_name);
2269 if (namelen > 255)
2270 continue;
2271 if (has_extension(de->d_name, ".lock"))
2272 continue;
2273 memcpy(log + baselen, de->d_name, namelen+1);
2274 if (stat(git_path("logs/%s", log), &st) < 0)
2275 continue;
2276 if (S_ISDIR(st.st_mode)) {
2277 retval = do_for_each_reflog(log, fn, cb_data);
2278 } else {
2279 unsigned char sha1[20];
2280 if (read_ref_full(log, sha1, 0, NULL))
2281 retval = error("bad ref for %s", log);
2282 else
2283 retval = fn(log, sha1, 0, cb_data);
eb8381c8 2284 }
93c603fc
MH
2285 if (retval)
2286 break;
eb8381c8 2287 }
93c603fc
MH
2288 free(log);
2289 closedir(d);
eb8381c8
NP
2290 return retval;
2291}
2292
2293int for_each_reflog(each_ref_fn fn, void *cb_data)
2294{
2295 return do_for_each_reflog("", fn, cb_data);
2296}
3d9f037c
CR
2297
2298int update_ref(const char *action, const char *refname,
2299 const unsigned char *sha1, const unsigned char *oldval,
2300 int flags, enum action_on_err onerr)
2301{
2302 static struct ref_lock *lock;
2303 lock = lock_any_ref_for_update(refname, oldval, flags);
2304 if (!lock) {
2305 const char *str = "Cannot lock the ref '%s'.";
2306 switch (onerr) {
2307 case MSG_ON_ERR: error(str, refname); break;
2308 case DIE_ON_ERR: die(str, refname); break;
2309 case QUIET_ON_ERR: break;
2310 }
2311 return 1;
2312 }
2313 if (write_ref_sha1(lock, sha1, action) < 0) {
2314 const char *str = "Cannot update the ref '%s'.";
2315 switch (onerr) {
2316 case MSG_ON_ERR: error(str, refname); break;
2317 case DIE_ON_ERR: die(str, refname); break;
2318 case QUIET_ON_ERR: break;
2319 }
2320 return 1;
2321 }
2322 return 0;
2323}
cda69f48 2324
5483f799 2325struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2326{
2327 for ( ; list; list = list->next)
2328 if (!strcmp(list->name, name))
5483f799 2329 return (struct ref *)list;
cda69f48
JK
2330 return NULL;
2331}
7c2b3029
JK
2332
2333/*
2334 * generate a format suitable for scanf from a ref_rev_parse_rules
2335 * rule, that is replace the "%.*s" spec with a "%s" spec
2336 */
2337static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2338{
2339 char *spec;
2340
2341 spec = strstr(rule, "%.*s");
2342 if (!spec || strstr(spec + 4, "%.*s"))
2343 die("invalid rule in ref_rev_parse_rules: %s", rule);
2344
2345 /* copy all until spec */
2346 strncpy(scanf_fmt, rule, spec - rule);
2347 scanf_fmt[spec - rule] = '\0';
2348 /* copy new spec */
2349 strcat(scanf_fmt, "%s");
2350 /* copy remaining rule */
2351 strcat(scanf_fmt, spec + 4);
2352
2353 return;
2354}
2355
dfefa935 2356char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2357{
2358 int i;
2359 static char **scanf_fmts;
2360 static int nr_rules;
2361 char *short_name;
2362
2363 /* pre generate scanf formats from ref_rev_parse_rules[] */
2364 if (!nr_rules) {
2365 size_t total_len = 0;
2366
2367 /* the rule list is NULL terminated, count them first */
2368 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2369 /* no +1 because strlen("%s") < strlen("%.*s") */
2370 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2371
2372 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2373
2374 total_len = 0;
2375 for (i = 0; i < nr_rules; i++) {
2376 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2377 + total_len;
2378 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2379 total_len += strlen(ref_rev_parse_rules[i]);
2380 }
2381 }
2382
2383 /* bail out if there are no rules */
2384 if (!nr_rules)
dfefa935 2385 return xstrdup(refname);
7c2b3029 2386
dfefa935
MH
2387 /* buffer for scanf result, at most refname must fit */
2388 short_name = xstrdup(refname);
7c2b3029
JK
2389
2390 /* skip first rule, it will always match */
2391 for (i = nr_rules - 1; i > 0 ; --i) {
2392 int j;
6e7b3309 2393 int rules_to_fail = i;
7c2b3029
JK
2394 int short_name_len;
2395
dfefa935 2396 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2397 continue;
2398
2399 short_name_len = strlen(short_name);
2400
6e7b3309
BW
2401 /*
2402 * in strict mode, all (except the matched one) rules
2403 * must fail to resolve to a valid non-ambiguous ref
2404 */
2405 if (strict)
2406 rules_to_fail = nr_rules;
2407
7c2b3029
JK
2408 /*
2409 * check if the short name resolves to a valid ref,
2410 * but use only rules prior to the matched one
2411 */
6e7b3309 2412 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2413 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2414 char refname[PATH_MAX];
2415
6e7b3309
BW
2416 /* skip matched rule */
2417 if (i == j)
2418 continue;
2419
7c2b3029
JK
2420 /*
2421 * the short name is ambiguous, if it resolves
2422 * (with this previous rule) to a valid ref
2423 * read_ref() returns 0 on success
2424 */
2425 mksnpath(refname, sizeof(refname),
2426 rule, short_name_len, short_name);
c6893323 2427 if (ref_exists(refname))
7c2b3029
JK
2428 break;
2429 }
2430
2431 /*
2432 * short name is non-ambiguous if all previous rules
2433 * haven't resolved to a valid ref
2434 */
6e7b3309 2435 if (j == rules_to_fail)
7c2b3029
JK
2436 return short_name;
2437 }
2438
2439 free(short_name);
dfefa935 2440 return xstrdup(refname);
7c2b3029 2441}