resolve_ref_unsafe(): extract function handle_missing_loose_ref()
[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"
daebaa78 6#include "string-list.h"
95fc7512 7
bc5fd6d3
MH
8/*
9 * Make sure "ref" is something reasonable to have under ".git/refs/";
10 * We do not like it if:
11 *
12 * - any path component of it begins with ".", or
13 * - it has double dots "..", or
14 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
15 * - it ends with a "/".
16 * - it ends with ".lock"
17 * - it contains a "\" (backslash)
18 */
f4204ab9 19
bc5fd6d3
MH
20/* Return true iff ch is not allowed in reference names. */
21static inline int bad_ref_char(int ch)
22{
23 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
24 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
25 return 1;
26 /* 2.13 Pattern Matching Notation */
27 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
28 return 1;
29 return 0;
30}
31
32/*
33 * Try to read one refname component from the front of refname. Return
34 * the length of the component found, or -1 if the component is not
35 * legal.
36 */
37static int check_refname_component(const char *refname, int flags)
38{
39 const char *cp;
40 char last = '\0';
41
42 for (cp = refname; ; cp++) {
43 char ch = *cp;
44 if (ch == '\0' || ch == '/')
45 break;
46 if (bad_ref_char(ch))
47 return -1; /* Illegal character in refname. */
48 if (last == '.' && ch == '.')
49 return -1; /* Refname contains "..". */
50 if (last == '@' && ch == '{')
51 return -1; /* Refname contains "@{". */
52 last = ch;
53 }
54 if (cp == refname)
dac529e4 55 return 0; /* Component has zero length. */
bc5fd6d3
MH
56 if (refname[0] == '.') {
57 if (!(flags & REFNAME_DOT_COMPONENT))
58 return -1; /* Component starts with '.'. */
59 /*
60 * Even if leading dots are allowed, don't allow "."
61 * as a component (".." is prevented by a rule above).
62 */
63 if (refname[1] == '\0')
64 return -1; /* Component equals ".". */
65 }
66 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
67 return -1; /* Refname ends with ".lock". */
68 return cp - refname;
69}
70
71int check_refname_format(const char *refname, int flags)
72{
73 int component_len, component_count = 0;
74
cdfd9483
FC
75 if (!strcmp(refname, "@"))
76 /* Refname is a single character '@'. */
77 return -1;
78
bc5fd6d3
MH
79 while (1) {
80 /* We are at the start of a path component. */
81 component_len = check_refname_component(refname, flags);
dac529e4 82 if (component_len <= 0) {
bc5fd6d3
MH
83 if ((flags & REFNAME_REFSPEC_PATTERN) &&
84 refname[0] == '*' &&
85 (refname[1] == '\0' || refname[1] == '/')) {
86 /* Accept one wildcard as a full refname component. */
87 flags &= ~REFNAME_REFSPEC_PATTERN;
88 component_len = 1;
89 } else {
90 return -1;
91 }
92 }
93 component_count++;
94 if (refname[component_len] == '\0')
95 break;
96 /* Skip to next component. */
97 refname += component_len + 1;
98 }
99
100 if (refname[component_len - 1] == '.')
101 return -1; /* Refname ends with '.'. */
102 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
103 return -1; /* Refname has only one component. */
104 return 0;
105}
106
107struct ref_entry;
e1e22e37 108
28e6a34e
MH
109/*
110 * Information used (along with the information in ref_entry) to
111 * describe a single cached reference. This data structure only
112 * occurs embedded in a union in struct ref_entry, and only when
113 * (ref_entry->flag & REF_DIR) is zero.
114 */
593f1bb8 115struct ref_value {
6c6f58df
MH
116 /*
117 * The name of the object to which this reference resolves
118 * (which may be a tag object). If REF_ISBROKEN, this is
119 * null. If REF_ISSYMREF, then this is the name of the object
120 * referred to by the last reference in the symlink chain.
121 */
593f1bb8 122 unsigned char sha1[20];
6c6f58df
MH
123
124 /*
125 * If REF_KNOWS_PEELED, then this field holds the peeled value
126 * of this reference, or null if the reference is known not to
2312a793
MH
127 * be peelable. See the documentation for peel_ref() for an
128 * exact definition of "peelable".
6c6f58df 129 */
593f1bb8
MH
130 unsigned char peeled[20];
131};
132
f006c42a
MH
133struct ref_cache;
134
28e6a34e
MH
135/*
136 * Information used (along with the information in ref_entry) to
137 * describe a level in the hierarchy of references. This data
138 * structure only occurs embedded in a union in struct ref_entry, and
139 * only when (ref_entry.flag & REF_DIR) is set. In that case,
140 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
141 * in the directory have already been read:
142 *
143 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
144 * or packed references, already read.
145 *
146 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
147 * references that hasn't been read yet (nor has any of its
148 * subdirectories).
149 *
150 * Entries within a directory are stored within a growable array of
151 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
152 * sorted are sorted by their component name in strcmp() order and the
153 * remaining entries are unsorted.
154 *
155 * Loose references are read lazily, one directory at a time. When a
156 * directory of loose references is read, then all of the references
157 * in that directory are stored, and REF_INCOMPLETE stubs are created
158 * for any subdirectories, but the subdirectories themselves are not
159 * read. The reading is triggered by get_ref_dir().
160 */
d3177275 161struct ref_dir {
e9c4c111 162 int nr, alloc;
e6ed3ca6
MH
163
164 /*
165 * Entries with index 0 <= i < sorted are sorted by name. New
166 * entries are appended to the list unsorted, and are sorted
167 * only when required; thus we avoid the need to sort the list
168 * after the addition of every reference.
169 */
170 int sorted;
171
f006c42a
MH
172 /* A pointer to the ref_cache that contains this ref_dir. */
173 struct ref_cache *ref_cache;
174
d3177275 175 struct ref_entry **entries;
e9c4c111
JP
176};
177
89df9c84
MH
178/*
179 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01,
180 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see
181 * refs.h.
182 */
183
184/*
185 * The field ref_entry->u.value.peeled of this value entry contains
186 * the correct peeled value for the reference, which might be
187 * null_sha1 if the reference is not a tag or if it is broken.
188 */
432ad41e 189#define REF_KNOWS_PEELED 0x08
28e6a34e
MH
190
191/* ref_entry represents a directory of references */
432ad41e 192#define REF_DIR 0x10
cf0adba7 193
28e6a34e
MH
194/*
195 * Entry has not yet been read from disk (used only for REF_DIR
196 * entries representing loose references)
197 */
198#define REF_INCOMPLETE 0x20
199
432ad41e
MH
200/*
201 * A ref_entry represents either a reference or a "subdirectory" of
28e6a34e
MH
202 * references.
203 *
204 * Each directory in the reference namespace is represented by a
205 * ref_entry with (flags & REF_DIR) set and containing a subdir member
206 * that holds the entries in that directory that have been read so
207 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
208 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
209 * used for loose reference directories.
210 *
211 * References are represented by a ref_entry with (flags & REF_DIR)
212 * unset and a value member that describes the reference's value. The
213 * flag member is at the ref_entry level, but it is also needed to
214 * interpret the contents of the value field (in other words, a
215 * ref_value object is not very much use without the enclosing
216 * ref_entry).
432ad41e
MH
217 *
218 * Reference names cannot end with slash and directories' names are
219 * always stored with a trailing slash (except for the top-level
220 * directory, which is always denoted by ""). This has two nice
221 * consequences: (1) when the entries in each subdir are sorted
222 * lexicographically by name (as they usually are), the references in
223 * a whole tree can be generated in lexicographic order by traversing
224 * the tree in left-to-right, depth-first order; (2) the names of
225 * references and subdirectories cannot conflict, and therefore the
226 * presence of an empty subdirectory does not block the creation of a
227 * similarly-named reference. (The fact that reference names with the
228 * same leading components can conflict *with each other* is a
229 * separate issue that is regulated by is_refname_available().)
230 *
231 * Please note that the name field contains the fully-qualified
232 * reference (or subdirectory) name. Space could be saved by only
233 * storing the relative names. But that would require the full names
234 * to be generated on the fly when iterating in do_for_each_ref(), and
235 * would break callback functions, who have always been able to assume
236 * that the name strings that they are passed will not be freed during
237 * the iteration.
238 */
bc5fd6d3
MH
239struct ref_entry {
240 unsigned char flag; /* ISSYMREF? ISPACKED? */
593f1bb8 241 union {
432ad41e
MH
242 struct ref_value value; /* if not (flags&REF_DIR) */
243 struct ref_dir subdir; /* if (flags&REF_DIR) */
593f1bb8 244 } u;
432ad41e
MH
245 /*
246 * The full name of the reference (e.g., "refs/heads/master")
247 * or the full name of the directory with a trailing slash
248 * (e.g., "refs/heads/"):
249 */
bc5fd6d3
MH
250 char name[FLEX_ARRAY];
251};
e1e22e37 252
28e6a34e
MH
253static void read_loose_refs(const char *dirname, struct ref_dir *dir);
254
d7826d54
MH
255static struct ref_dir *get_ref_dir(struct ref_entry *entry)
256{
28e6a34e 257 struct ref_dir *dir;
d7826d54 258 assert(entry->flag & REF_DIR);
28e6a34e
MH
259 dir = &entry->u.subdir;
260 if (entry->flag & REF_INCOMPLETE) {
261 read_loose_refs(entry->name, dir);
262 entry->flag &= ~REF_INCOMPLETE;
263 }
264 return dir;
d7826d54
MH
265}
266
cddc4258
MH
267static struct ref_entry *create_ref_entry(const char *refname,
268 const unsigned char *sha1, int flag,
269 int check_name)
e1e22e37
LT
270{
271 int len;
cddc4258 272 struct ref_entry *ref;
e1e22e37 273
09116a1c 274 if (check_name &&
dfefa935
MH
275 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
276 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
277 len = strlen(refname) + 1;
278 ref = xmalloc(sizeof(struct ref_entry) + len);
593f1bb8
MH
279 hashcpy(ref->u.value.sha1, sha1);
280 hashclr(ref->u.value.peeled);
cddc4258
MH
281 memcpy(ref->name, refname, len);
282 ref->flag = flag;
283 return ref;
284}
285
432ad41e
MH
286static void clear_ref_dir(struct ref_dir *dir);
287
732134ed
MH
288static void free_ref_entry(struct ref_entry *entry)
289{
27b5587c
MH
290 if (entry->flag & REF_DIR) {
291 /*
292 * Do not use get_ref_dir() here, as that might
293 * trigger the reading of loose refs.
294 */
295 clear_ref_dir(&entry->u.subdir);
296 }
732134ed
MH
297 free(entry);
298}
299
432ad41e
MH
300/*
301 * Add a ref_entry to the end of dir (unsorted). Entry is always
302 * stored directly in dir; no recursion into subdirectories is
303 * done.
304 */
305static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
cddc4258 306{
432ad41e
MH
307 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
308 dir->entries[dir->nr++] = entry;
654ad400
MH
309 /* optimize for the case that entries are added in order */
310 if (dir->nr == 1 ||
311 (dir->nr == dir->sorted + 1 &&
312 strcmp(dir->entries[dir->nr - 2]->name,
313 dir->entries[dir->nr - 1]->name) < 0))
314 dir->sorted = dir->nr;
c774aab9
JP
315}
316
432ad41e
MH
317/*
318 * Clear and free all entries in dir, recursively.
319 */
d3177275 320static void clear_ref_dir(struct ref_dir *dir)
bc5fd6d3
MH
321{
322 int i;
d3177275
MH
323 for (i = 0; i < dir->nr; i++)
324 free_ref_entry(dir->entries[i]);
325 free(dir->entries);
326 dir->sorted = dir->nr = dir->alloc = 0;
327 dir->entries = NULL;
bc5fd6d3
MH
328}
329
432ad41e
MH
330/*
331 * Create a struct ref_entry object for the specified dirname.
332 * dirname is the name of the directory with a trailing slash (e.g.,
333 * "refs/heads/") or "" for the top-level directory.
334 */
f006c42a 335static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
b9146f51
RS
336 const char *dirname, size_t len,
337 int incomplete)
432ad41e
MH
338{
339 struct ref_entry *direntry;
432ad41e 340 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
b9146f51
RS
341 memcpy(direntry->name, dirname, len);
342 direntry->name[len] = '\0';
f006c42a 343 direntry->u.subdir.ref_cache = ref_cache;
28e6a34e 344 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
432ad41e
MH
345 return direntry;
346}
347
e9c4c111 348static int ref_entry_cmp(const void *a, const void *b)
c774aab9 349{
e9c4c111
JP
350 struct ref_entry *one = *(struct ref_entry **)a;
351 struct ref_entry *two = *(struct ref_entry **)b;
352 return strcmp(one->name, two->name);
353}
c774aab9 354
d3177275 355static void sort_ref_dir(struct ref_dir *dir);
bc5fd6d3 356
e1980c9d
JH
357struct string_slice {
358 size_t len;
359 const char *str;
360};
361
362static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
363{
c971ddfd
RS
364 const struct string_slice *key = key_;
365 const struct ref_entry *ent = *(const struct ref_entry * const *)ent_;
366 int cmp = strncmp(key->str, ent->name, key->len);
e1980c9d
JH
367 if (cmp)
368 return cmp;
c971ddfd 369 return '\0' - (unsigned char)ent->name[key->len];
e1980c9d
JH
370}
371
432ad41e 372/*
9fc0a648
MH
373 * Return the index of the entry with the given refname from the
374 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if
375 * no such entry is found. dir must already be complete.
432ad41e 376 */
9fc0a648 377static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len)
bc5fd6d3 378{
e1980c9d
JH
379 struct ref_entry **r;
380 struct string_slice key;
bc5fd6d3 381
432ad41e 382 if (refname == NULL || !dir->nr)
9fc0a648 383 return -1;
bc5fd6d3 384
d3177275 385 sort_ref_dir(dir);
e1980c9d
JH
386 key.len = len;
387 key.str = refname;
388 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
389 ref_entry_cmp_sslice);
bc5fd6d3
MH
390
391 if (r == NULL)
9fc0a648 392 return -1;
bc5fd6d3 393
9fc0a648 394 return r - dir->entries;
bc5fd6d3
MH
395}
396
f348ac92
MH
397/*
398 * Search for a directory entry directly within dir (without
399 * recursing). Sort dir if necessary. subdirname must be a directory
400 * name (i.e., end in '/'). If mkdir is set, then create the
401 * directory if it is missing; otherwise, return NULL if the desired
28e6a34e 402 * directory cannot be found. dir must already be complete.
f348ac92 403 */
3f3aa1bc 404static struct ref_dir *search_for_subdir(struct ref_dir *dir,
dd02e728
RS
405 const char *subdirname, size_t len,
406 int mkdir)
f348ac92 407{
9fc0a648
MH
408 int entry_index = search_ref_dir(dir, subdirname, len);
409 struct ref_entry *entry;
410 if (entry_index == -1) {
f348ac92
MH
411 if (!mkdir)
412 return NULL;
28e6a34e
MH
413 /*
414 * Since dir is complete, the absence of a subdir
415 * means that the subdir really doesn't exist;
416 * therefore, create an empty record for it but mark
417 * the record complete.
418 */
b9146f51 419 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
f348ac92 420 add_entry_to_dir(dir, entry);
9fc0a648
MH
421 } else {
422 entry = dir->entries[entry_index];
f348ac92 423 }
3f3aa1bc 424 return get_ref_dir(entry);
f348ac92
MH
425}
426
432ad41e
MH
427/*
428 * If refname is a reference name, find the ref_dir within the dir
429 * tree that should hold refname. If refname is a directory name
430 * (i.e., ends in '/'), then return that ref_dir itself. dir must
28e6a34e
MH
431 * represent the top-level directory and must already be complete.
432 * Sort ref_dirs and recurse into subdirectories as necessary. If
433 * mkdir is set, then create any missing directories; otherwise,
434 * return NULL if the desired directory cannot be found.
432ad41e
MH
435 */
436static struct ref_dir *find_containing_dir(struct ref_dir *dir,
437 const char *refname, int mkdir)
438{
5fa04418 439 const char *slash;
5fa04418 440 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
dd02e728 441 size_t dirnamelen = slash - refname + 1;
3f3aa1bc 442 struct ref_dir *subdir;
dd02e728 443 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
663c1295
JH
444 if (!subdir) {
445 dir = NULL;
f348ac92 446 break;
432ad41e 447 }
3f3aa1bc 448 dir = subdir;
432ad41e
MH
449 }
450
432ad41e
MH
451 return dir;
452}
453
454/*
455 * Find the value entry with the given name in dir, sorting ref_dirs
456 * and recursing into subdirectories as necessary. If the name is not
457 * found or it corresponds to a directory entry, return NULL.
458 */
459static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
460{
9fc0a648 461 int entry_index;
432ad41e
MH
462 struct ref_entry *entry;
463 dir = find_containing_dir(dir, refname, 0);
464 if (!dir)
465 return NULL;
9fc0a648
MH
466 entry_index = search_ref_dir(dir, refname, strlen(refname));
467 if (entry_index == -1)
468 return NULL;
469 entry = dir->entries[entry_index];
470 return (entry->flag & REF_DIR) ? NULL : entry;
432ad41e
MH
471}
472
506a760d
MH
473/*
474 * Remove the entry with the given name from dir, recursing into
475 * subdirectories as necessary. If refname is the name of a directory
476 * (i.e., ends with '/'), then remove the directory and its contents.
477 * If the removal was successful, return the number of entries
478 * remaining in the directory entry that contained the deleted entry.
479 * If the name was not found, return -1. Please note that this
480 * function only deletes the entry from the cache; it does not delete
481 * it from the filesystem or ensure that other cache entries (which
482 * might be symbolic references to the removed entry) are updated.
483 * Nor does it remove any containing dir entries that might be made
484 * empty by the removal. dir must represent the top-level directory
485 * and must already be complete.
486 */
487static int remove_entry(struct ref_dir *dir, const char *refname)
488{
489 int refname_len = strlen(refname);
490 int entry_index;
491 struct ref_entry *entry;
492 int is_dir = refname[refname_len - 1] == '/';
493 if (is_dir) {
494 /*
495 * refname represents a reference directory. Remove
496 * the trailing slash; otherwise we will get the
497 * directory *representing* refname rather than the
498 * one *containing* it.
499 */
500 char *dirname = xmemdupz(refname, refname_len - 1);
501 dir = find_containing_dir(dir, dirname, 0);
502 free(dirname);
503 } else {
504 dir = find_containing_dir(dir, refname, 0);
505 }
506 if (!dir)
507 return -1;
508 entry_index = search_ref_dir(dir, refname, refname_len);
509 if (entry_index == -1)
510 return -1;
511 entry = dir->entries[entry_index];
512
513 memmove(&dir->entries[entry_index],
514 &dir->entries[entry_index + 1],
515 (dir->nr - entry_index - 1) * sizeof(*dir->entries)
516 );
517 dir->nr--;
518 if (dir->sorted > entry_index)
519 dir->sorted--;
520 free_ref_entry(entry);
521 return dir->nr;
432ad41e
MH
522}
523
524/*
525 * Add a ref_entry to the ref_dir (unsorted), recursing into
526 * subdirectories as necessary. dir must represent the top-level
527 * directory. Return 0 on success.
528 */
529static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
530{
531 dir = find_containing_dir(dir, ref->name, 1);
532 if (!dir)
533 return -1;
534 add_entry_to_dir(dir, ref);
535 return 0;
536}
537
202a56a9
MH
538/*
539 * Emit a warning and return true iff ref1 and ref2 have the same name
540 * and the same sha1. Die if they have the same name but different
541 * sha1s.
542 */
543static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
544{
432ad41e 545 if (strcmp(ref1->name, ref2->name))
202a56a9 546 return 0;
432ad41e
MH
547
548 /* Duplicate name; make sure that they don't conflict: */
549
550 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
551 /* This is impossible by construction */
552 die("Reference directory conflict: %s", ref1->name);
553
554 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
555 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
556
557 warning("Duplicated ref: %s", ref1->name);
558 return 1;
202a56a9
MH
559}
560
e6ed3ca6 561/*
432ad41e
MH
562 * Sort the entries in dir non-recursively (if they are not already
563 * sorted) and remove any duplicate entries.
e6ed3ca6 564 */
d3177275 565static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 566{
202a56a9 567 int i, j;
81a79d8e 568 struct ref_entry *last = NULL;
c774aab9 569
e6ed3ca6
MH
570 /*
571 * This check also prevents passing a zero-length array to qsort(),
572 * which is a problem on some platforms.
573 */
d3177275 574 if (dir->sorted == dir->nr)
e9c4c111 575 return;
c774aab9 576
d3177275 577 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 578
81a79d8e
MH
579 /* Remove any duplicates: */
580 for (i = 0, j = 0; j < dir->nr; j++) {
581 struct ref_entry *entry = dir->entries[j];
582 if (last && is_dup_ref(last, entry))
583 free_ref_entry(entry);
584 else
585 last = dir->entries[i++] = entry;
e9c4c111 586 }
81a79d8e 587 dir->sorted = dir->nr = i;
e9c4c111 588}
c774aab9 589
fcce1703
MH
590/* Include broken references in a do_for_each_ref*() iteration: */
591#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
c774aab9 592
662428f4
MH
593/*
594 * Return true iff the reference described by entry can be resolved to
595 * an object in the database. Emit a warning if the referred-to
596 * object does not exist.
597 */
598static int ref_resolves_to_object(struct ref_entry *entry)
599{
600 if (entry->flag & REF_ISBROKEN)
601 return 0;
602 if (!has_sha1_file(entry->u.value.sha1)) {
603 error("%s does not point to a valid object!", entry->name);
604 return 0;
605 }
606 return 1;
607}
c774aab9 608
7d76fdc8
MH
609/*
610 * current_ref is a performance hack: when iterating over references
611 * using the for_each_ref*() functions, current_ref is set to the
612 * current reference's entry before calling the callback function. If
613 * the callback function calls peel_ref(), then peel_ref() first
614 * checks whether the reference to be peeled is the current reference
615 * (it usually is) and if so, returns that reference's peeled version
616 * if it is available. This avoids a refname lookup in a common case.
617 */
bc5fd6d3 618static struct ref_entry *current_ref;
c774aab9 619
624cac35
MH
620typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data);
621
622struct ref_entry_cb {
623 const char *base;
624 int trim;
625 int flags;
626 each_ref_fn *fn;
627 void *cb_data;
628};
629
fcce1703 630/*
624cac35
MH
631 * Handle one reference in a do_for_each_ref*()-style iteration,
632 * calling an each_ref_fn for each entry.
fcce1703 633 */
624cac35 634static int do_one_ref(struct ref_entry *entry, void *cb_data)
bc5fd6d3 635{
624cac35 636 struct ref_entry_cb *data = cb_data;
429213e4 637 int retval;
624cac35 638 if (prefixcmp(entry->name, data->base))
bc5fd6d3 639 return 0;
c774aab9 640
624cac35 641 if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
662428f4 642 !ref_resolves_to_object(entry))
bc5fd6d3 643 return 0;
c774aab9 644
bc5fd6d3 645 current_ref = entry;
624cac35
MH
646 retval = data->fn(entry->name + data->trim, entry->u.value.sha1,
647 entry->flag, data->cb_data);
429213e4
MH
648 current_ref = NULL;
649 return retval;
bc5fd6d3 650}
c774aab9 651
c36b5bc2 652/*
d3177275 653 * Call fn for each reference in dir that has index in the range
432ad41e
MH
654 * offset <= index < dir->nr. Recurse into subdirectories that are in
655 * that index range, sorting them before iterating. This function
624cac35
MH
656 * does not sort dir itself; it should be sorted beforehand. fn is
657 * called for all references, including broken ones.
c36b5bc2 658 */
624cac35
MH
659static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset,
660 each_ref_entry_fn fn, void *cb_data)
c36b5bc2
MH
661{
662 int i;
d3177275
MH
663 assert(dir->sorted == dir->nr);
664 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
665 struct ref_entry *entry = dir->entries[i];
666 int retval;
667 if (entry->flag & REF_DIR) {
d7826d54
MH
668 struct ref_dir *subdir = get_ref_dir(entry);
669 sort_ref_dir(subdir);
624cac35 670 retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data);
432ad41e 671 } else {
624cac35 672 retval = fn(entry, cb_data);
432ad41e 673 }
c36b5bc2
MH
674 if (retval)
675 return retval;
676 }
677 return 0;
678}
679
b3fd060f 680/*
d3177275 681 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
682 * by refname. Recurse into subdirectories. If a value entry appears
683 * in both dir1 and dir2, then only process the version that is in
684 * dir2. The input dirs must already be sorted, but subdirs will be
624cac35
MH
685 * sorted as needed. fn is called for all references, including
686 * broken ones.
b3fd060f 687 */
624cac35
MH
688static int do_for_each_entry_in_dirs(struct ref_dir *dir1,
689 struct ref_dir *dir2,
690 each_ref_entry_fn fn, void *cb_data)
b3fd060f
MH
691{
692 int retval;
693 int i1 = 0, i2 = 0;
694
d3177275
MH
695 assert(dir1->sorted == dir1->nr);
696 assert(dir2->sorted == dir2->nr);
432ad41e
MH
697 while (1) {
698 struct ref_entry *e1, *e2;
699 int cmp;
700 if (i1 == dir1->nr) {
624cac35 701 return do_for_each_entry_in_dir(dir2, i2, fn, cb_data);
432ad41e
MH
702 }
703 if (i2 == dir2->nr) {
624cac35 704 return do_for_each_entry_in_dir(dir1, i1, fn, cb_data);
432ad41e
MH
705 }
706 e1 = dir1->entries[i1];
707 e2 = dir2->entries[i2];
708 cmp = strcmp(e1->name, e2->name);
709 if (cmp == 0) {
710 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
711 /* Both are directories; descend them in parallel. */
d7826d54
MH
712 struct ref_dir *subdir1 = get_ref_dir(e1);
713 struct ref_dir *subdir2 = get_ref_dir(e2);
714 sort_ref_dir(subdir1);
715 sort_ref_dir(subdir2);
624cac35
MH
716 retval = do_for_each_entry_in_dirs(
717 subdir1, subdir2, fn, cb_data);
432ad41e
MH
718 i1++;
719 i2++;
720 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
721 /* Both are references; ignore the one from dir1. */
624cac35 722 retval = fn(e2, cb_data);
432ad41e
MH
723 i1++;
724 i2++;
725 } else {
726 die("conflict between reference and directory: %s",
727 e1->name);
728 }
b3fd060f 729 } else {
432ad41e
MH
730 struct ref_entry *e;
731 if (cmp < 0) {
732 e = e1;
b3fd060f 733 i1++;
432ad41e
MH
734 } else {
735 e = e2;
736 i2++;
737 }
738 if (e->flag & REF_DIR) {
d7826d54
MH
739 struct ref_dir *subdir = get_ref_dir(e);
740 sort_ref_dir(subdir);
624cac35
MH
741 retval = do_for_each_entry_in_dir(
742 subdir, 0, fn, cb_data);
432ad41e 743 } else {
624cac35 744 retval = fn(e, cb_data);
b3fd060f
MH
745 }
746 }
747 if (retval)
748 return retval;
749 }
b3fd060f
MH
750}
751
d66da478
MH
752/*
753 * Return true iff refname1 and refname2 conflict with each other.
754 * Two reference names conflict if one of them exactly matches the
755 * leading components of the other; e.g., "foo/bar" conflicts with
756 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
757 * "foo/barbados".
758 */
759static int names_conflict(const char *refname1, const char *refname2)
760{
5a4d4947
MH
761 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
762 ;
763 return (*refname1 == '\0' && *refname2 == '/')
764 || (*refname1 == '/' && *refname2 == '\0');
765}
766
767struct name_conflict_cb {
768 const char *refname;
769 const char *oldrefname;
770 const char *conflicting_refname;
771};
772
624cac35 773static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
5a4d4947
MH
774{
775 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
624cac35 776 if (data->oldrefname && !strcmp(data->oldrefname, entry->name))
5a4d4947 777 return 0;
624cac35
MH
778 if (names_conflict(data->refname, entry->name)) {
779 data->conflicting_refname = entry->name;
5a4d4947 780 return 1;
d66da478 781 }
5a4d4947 782 return 0;
d66da478
MH
783}
784
bc5fd6d3
MH
785/*
786 * Return true iff a reference named refname could be created without
624cac35 787 * conflicting with the name of an existing reference in dir. If
5a4d4947
MH
788 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
789 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
790 * operation).
791 */
792static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 793 struct ref_dir *dir)
bc5fd6d3 794{
5a4d4947
MH
795 struct name_conflict_cb data;
796 data.refname = refname;
797 data.oldrefname = oldrefname;
798 data.conflicting_refname = NULL;
799
d3177275 800 sort_ref_dir(dir);
624cac35 801 if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) {
5a4d4947
MH
802 error("'%s' exists; cannot create '%s'",
803 data.conflicting_refname, refname);
804 return 0;
bc5fd6d3
MH
805 }
806 return 1;
e1e22e37
LT
807}
808
5e290ff7
JH
809/*
810 * Future: need to be in "struct repository"
811 * when doing a full libification.
812 */
79c7ca54
MH
813static struct ref_cache {
814 struct ref_cache *next;
d12229f5
MH
815 struct ref_entry *loose;
816 struct ref_entry *packed;
9da31cb0
MH
817 /*
818 * The submodule name, or "" for the main repo. We allocate
819 * length 1 rather than FLEX_ARRAY so that the main ref_cache
820 * is initialized correctly.
821 */
822 char name[1];
823} ref_cache, *submodule_ref_caches;
0e88c130 824
760c4512 825static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 826{
d12229f5
MH
827 if (refs->packed) {
828 free_ref_entry(refs->packed);
829 refs->packed = NULL;
830 }
5e290ff7 831}
e1e22e37 832
760c4512
MH
833static void clear_loose_ref_cache(struct ref_cache *refs)
834{
d12229f5
MH
835 if (refs->loose) {
836 free_ref_entry(refs->loose);
837 refs->loose = NULL;
838 }
760c4512
MH
839}
840
79c7ca54 841static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 842{
ce40979c 843 int len;
79c7ca54 844 struct ref_cache *refs;
ce40979c
MH
845 if (!submodule)
846 submodule = "";
847 len = strlen(submodule) + 1;
79c7ca54 848 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 849 memcpy(refs->name, submodule, len);
e5dbf605
MH
850 return refs;
851}
852
4349a668 853/*
79c7ca54 854 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
855 * the main repository, use submodule==NULL. The returned structure
856 * will be allocated and initialized but not necessarily populated; it
857 * should not be freed.
858 */
79c7ca54 859static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 860{
9da31cb0
MH
861 struct ref_cache *refs;
862
863 if (!submodule || !*submodule)
864 return &ref_cache;
865
866 for (refs = submodule_ref_caches; refs; refs = refs->next)
0e88c130
MH
867 if (!strcmp(submodule, refs->name))
868 return refs;
0e88c130 869
79c7ca54 870 refs = create_ref_cache(submodule);
9da31cb0
MH
871 refs->next = submodule_ref_caches;
872 submodule_ref_caches = refs;
0e88c130 873 return refs;
4349a668
MH
874}
875
8be8bde7 876void invalidate_ref_cache(const char *submodule)
f130b116 877{
c5f29abd
MH
878 struct ref_cache *refs = get_ref_cache(submodule);
879 clear_packed_ref_cache(refs);
880 clear_loose_ref_cache(refs);
5e290ff7 881}
e1e22e37 882
3feb4f0c
MH
883/* The length of a peeled reference line in packed-refs, including EOL: */
884#define PEELED_LINE_LENGTH 42
885
694b7a19
MH
886/*
887 * The packed-refs header line that we write out. Perhaps other
888 * traits will be added later. The trailing space is required.
889 */
890static const char PACKED_REFS_HEADER[] =
891 "# pack-refs with: peeled fully-peeled \n";
892
bc5fd6d3
MH
893/*
894 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
895 * Return a pointer to the refname within the line (null-terminated),
896 * or NULL if there was a problem.
897 */
898static const char *parse_ref_line(char *line, unsigned char *sha1)
899{
900 /*
901 * 42: the answer to everything.
902 *
903 * In this case, it happens to be the answer to
904 * 40 (length of sha1 hex representation)
905 * +1 (space in between hex and name)
906 * +1 (newline at the end of the line)
907 */
908 int len = strlen(line) - 42;
909
910 if (len <= 0)
911 return NULL;
912 if (get_sha1_hex(line, sha1) < 0)
913 return NULL;
914 if (!isspace(line[40]))
915 return NULL;
916 line += 41;
917 if (isspace(*line))
918 return NULL;
919 if (line[len] != '\n')
920 return NULL;
921 line[len] = 0;
922
923 return line;
924}
925
c29c46fa
MH
926/*
927 * Read f, which is a packed-refs file, into dir.
928 *
929 * A comment line of the form "# pack-refs with: " may contain zero or
930 * more traits. We interpret the traits as follows:
931 *
932 * No traits:
933 *
934 * Probably no references are peeled. But if the file contains a
935 * peeled value for a reference, we will use it.
936 *
937 * peeled:
938 *
939 * References under "refs/tags/", if they *can* be peeled, *are*
940 * peeled in this file. References outside of "refs/tags/" are
941 * probably not peeled even if they could have been, but if we find
942 * a peeled value for such a reference we will use it.
943 *
944 * fully-peeled:
945 *
946 * All references in the file that can be peeled are peeled.
947 * Inversely (and this is more important), any references in the
948 * file for which no peeled value is recorded is not peelable. This
949 * trait should typically be written alongside "peeled" for
950 * compatibility with older clients, but we do not require it
951 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
952 */
d3177275 953static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 954{
e9c4c111 955 struct ref_entry *last = NULL;
f4204ab9 956 char refline[PATH_MAX];
c29c46fa 957 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
f4204ab9
JH
958
959 while (fgets(refline, sizeof(refline), f)) {
960 unsigned char sha1[20];
dfefa935 961 const char *refname;
f4204ab9
JH
962 static const char header[] = "# pack-refs with:";
963
964 if (!strncmp(refline, header, sizeof(header)-1)) {
965 const char *traits = refline + sizeof(header) - 1;
c29c46fa
MH
966 if (strstr(traits, " fully-peeled "))
967 peeled = PEELED_FULLY;
968 else if (strstr(traits, " peeled "))
969 peeled = PEELED_TAGS;
f4204ab9
JH
970 /* perhaps other traits later as well */
971 continue;
972 }
973
dfefa935
MH
974 refname = parse_ref_line(refline, sha1);
975 if (refname) {
c29c46fa
MH
976 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
977 if (peeled == PEELED_FULLY ||
978 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
979 last->flag |= REF_KNOWS_PEELED;
d3177275 980 add_ref(dir, last);
f4204ab9
JH
981 continue;
982 }
983 if (last &&
984 refline[0] == '^' &&
3feb4f0c
MH
985 strlen(refline) == PEELED_LINE_LENGTH &&
986 refline[PEELED_LINE_LENGTH - 1] == '\n' &&
c29c46fa 987 !get_sha1_hex(refline + 1, sha1)) {
593f1bb8 988 hashcpy(last->u.value.peeled, sha1);
c29c46fa
MH
989 /*
990 * Regardless of what the file header said,
991 * we definitely know the value of *this*
992 * reference:
993 */
994 last->flag |= REF_KNOWS_PEELED;
995 }
f4204ab9 996 }
f4204ab9
JH
997}
998
d3177275 999static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 1000{
d12229f5 1001 if (!refs->packed) {
4349a668
MH
1002 const char *packed_refs_file;
1003 FILE *f;
0bad611b 1004
b9146f51 1005 refs->packed = create_dir_entry(refs, "", 0, 0);
316b097a
MH
1006 if (*refs->name)
1007 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
1008 else
1009 packed_refs_file = git_path("packed-refs");
1010 f = fopen(packed_refs_file, "r");
e1e22e37 1011 if (f) {
d7826d54 1012 read_packed_refs(f, get_ref_dir(refs->packed));
e1e22e37 1013 fclose(f);
e1e22e37 1014 }
e1e22e37 1015 }
d7826d54 1016 return get_ref_dir(refs->packed);
e1e22e37
LT
1017}
1018
30249ee6
MH
1019void add_packed_ref(const char *refname, const unsigned char *sha1)
1020{
9da31cb0
MH
1021 add_ref(get_packed_refs(&ref_cache),
1022 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
30249ee6
MH
1023}
1024
abc39098 1025/*
28e6a34e
MH
1026 * Read the loose references from the namespace dirname into dir
1027 * (without recursing). dirname must end with '/'. dir must be the
1028 * directory entry corresponding to dirname.
abc39098 1029 */
423a1afc 1030static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 1031{
423a1afc 1032 struct ref_cache *refs = dir->ref_cache;
d3177275 1033 DIR *d;
0bad611b 1034 const char *path;
d5fdae67 1035 struct dirent *de;
abc39098 1036 int dirnamelen = strlen(dirname);
72b64b44 1037 struct strbuf refname;
0bad611b 1038
3b124823 1039 if (*refs->name)
66a3d20b 1040 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 1041 else
66a3d20b 1042 path = git_path("%s", dirname);
0bad611b 1043
d3177275 1044 d = opendir(path);
d5fdae67
MH
1045 if (!d)
1046 return;
1047
66a3d20b
MH
1048 strbuf_init(&refname, dirnamelen + 257);
1049 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
1050
1051 while ((de = readdir(d)) != NULL) {
1052 unsigned char sha1[20];
1053 struct stat st;
1054 int flag;
d5fdae67
MH
1055 const char *refdir;
1056
1057 if (de->d_name[0] == '.')
1058 continue;
d5fdae67
MH
1059 if (has_extension(de->d_name, ".lock"))
1060 continue;
72b64b44 1061 strbuf_addstr(&refname, de->d_name);
d5fdae67 1062 refdir = *refs->name
72b64b44
MH
1063 ? git_path_submodule(refs->name, "%s", refname.buf)
1064 : git_path("%s", refname.buf);
1065 if (stat(refdir, &st) < 0) {
1066 ; /* silently ignore */
1067 } else if (S_ISDIR(st.st_mode)) {
abc39098 1068 strbuf_addch(&refname, '/');
28e6a34e 1069 add_entry_to_dir(dir,
b9146f51
RS
1070 create_dir_entry(refs, refname.buf,
1071 refname.len, 1));
72b64b44 1072 } else {
3b124823 1073 if (*refs->name) {
f8948e2f 1074 hashclr(sha1);
0bad611b 1075 flag = 0;
72b64b44 1076 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
0bad611b 1077 hashclr(sha1);
98ac34b2 1078 flag |= REF_ISBROKEN;
0bad611b 1079 }
72b64b44 1080 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
1081 hashclr(sha1);
1082 flag |= REF_ISBROKEN;
1083 }
9f2fb4a3
MH
1084 add_entry_to_dir(dir,
1085 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 1086 }
66a3d20b 1087 strbuf_setlen(&refname, dirnamelen);
e1e22e37 1088 }
72b64b44 1089 strbuf_release(&refname);
d5fdae67 1090 closedir(d);
e1e22e37
LT
1091}
1092
d3177275 1093static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 1094{
d12229f5 1095 if (!refs->loose) {
28e6a34e
MH
1096 /*
1097 * Mark the top-level directory complete because we
1098 * are about to read the only subdirectory that can
1099 * hold references:
1100 */
b9146f51 1101 refs->loose = create_dir_entry(refs, "", 0, 0);
28e6a34e
MH
1102 /*
1103 * Create an incomplete entry for "refs/":
1104 */
1105 add_entry_to_dir(get_ref_dir(refs->loose),
b9146f51 1106 create_dir_entry(refs, "refs/", 5, 1));
e1e22e37 1107 }
d7826d54 1108 return get_ref_dir(refs->loose);
e1e22e37
LT
1109}
1110
ca8db142
LT
1111/* We allow "recursive" symbolic refs. Only within reason, though */
1112#define MAXDEPTH 5
0ebde32c
LT
1113#define MAXREFLEN (1024)
1114
e5fa45c1
JH
1115/*
1116 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
1117 * from the loose refs in ref_cache refs. Find <refname> in the
1118 * packed-refs file for the submodule.
e5fa45c1 1119 */
b0626608 1120static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 1121 const char *refname, unsigned char *sha1)
0ebde32c 1122{
2c5c66be 1123 struct ref_entry *ref;
d3177275 1124 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 1125
432ad41e 1126 ref = find_ref(dir, refname);
b0626608
MH
1127 if (ref == NULL)
1128 return -1;
1129
593f1bb8 1130 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 1131 return 0;
0ebde32c
LT
1132}
1133
b0626608 1134static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 1135 const char *refname, unsigned char *sha1,
dfefa935 1136 int recursion)
0ebde32c 1137{
064d51dc 1138 int fd, len;
0ebde32c 1139 char buffer[128], *p;
064d51dc 1140 char *path;
0ebde32c 1141
064d51dc 1142 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 1143 return -1;
064d51dc
MH
1144 path = *refs->name
1145 ? git_path_submodule(refs->name, "%s", refname)
1146 : git_path("%s", refname);
1147 fd = open(path, O_RDONLY);
0ebde32c 1148 if (fd < 0)
b0626608 1149 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
1150
1151 len = read(fd, buffer, sizeof(buffer)-1);
1152 close(fd);
1153 if (len < 0)
1154 return -1;
1155 while (len && isspace(buffer[len-1]))
1156 len--;
1157 buffer[len] = 0;
1158
1159 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 1160 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
1161 return 0;
1162
1163 /* Symref? */
1164 if (strncmp(buffer, "ref:", 4))
1165 return -1;
1166 p = buffer + 4;
1167 while (isspace(*p))
1168 p++;
1169
064d51dc 1170 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
1171}
1172
85be1fe3 1173int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
1174{
1175 int len = strlen(path), retval;
064d51dc 1176 char *submodule;
b0626608 1177 struct ref_cache *refs;
0ebde32c
LT
1178
1179 while (len && path[len-1] == '/')
1180 len--;
1181 if (!len)
1182 return -1;
b0626608
MH
1183 submodule = xstrndup(path, len);
1184 refs = get_ref_cache(submodule);
1185 free(submodule);
1186
064d51dc 1187 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
1188 return retval;
1189}
ca8db142 1190
4886b89f 1191/*
63331581
MH
1192 * Return the ref_entry for the given refname from the packed
1193 * references. If it does not exist, return NULL.
4886b89f 1194 */
63331581 1195static struct ref_entry *get_packed_ref(const char *refname)
c224ca7f 1196{
9da31cb0 1197 return find_ref(get_packed_refs(&ref_cache), refname);
c224ca7f
MH
1198}
1199
47f534bf
MH
1200/*
1201 * A loose ref file doesn't exist; check for a packed ref. The
1202 * options are forwarded from resolve_safe_unsafe().
1203 */
1204static const char *handle_missing_loose_ref(const char *refname,
1205 unsigned char *sha1,
1206 int reading,
1207 int *flag)
1208{
1209 struct ref_entry *entry;
1210
1211 /*
1212 * The loose reference file does not exist; check for a packed
1213 * reference.
1214 */
1215 entry = get_packed_ref(refname);
1216 if (entry) {
1217 hashcpy(sha1, entry->u.value.sha1);
1218 if (flag)
1219 *flag |= REF_ISPACKED;
1220 return refname;
1221 }
1222 /* The reference is not a packed reference, either. */
1223 if (reading) {
1224 return NULL;
1225 } else {
1226 hashclr(sha1);
1227 return refname;
1228 }
1229}
1230
8d68493f 1231const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 1232{
0104ca09
HO
1233 int depth = MAXDEPTH;
1234 ssize_t len;
a876ed83 1235 char buffer[256];
dfefa935 1236 static char refname_buffer[256];
ca8db142 1237
8da19775
JH
1238 if (flag)
1239 *flag = 0;
1240
dfefa935 1241 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
1242 return NULL;
1243
a876ed83 1244 for (;;) {
55956350 1245 char path[PATH_MAX];
a876ed83
JH
1246 struct stat st;
1247 char *buf;
1248 int fd;
8a65ff76 1249
a876ed83
JH
1250 if (--depth < 0)
1251 return NULL;
ca8db142 1252
dfefa935 1253 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 1254
a876ed83 1255 if (lstat(path, &st) < 0) {
47f534bf
MH
1256 if (errno == ENOENT)
1257 return handle_missing_loose_ref(refname, sha1,
1258 reading, flag);
1259 else
a876ed83 1260 return NULL;
a876ed83 1261 }
ca8db142 1262
a876ed83
JH
1263 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1264 if (S_ISLNK(st.st_mode)) {
1265 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
1266 if (len < 0)
1267 return NULL;
b54cb795 1268 buffer[len] = 0;
1f58a038
MH
1269 if (!prefixcmp(buffer, "refs/") &&
1270 !check_refname_format(buffer, 0)) {
dfefa935
MH
1271 strcpy(refname_buffer, buffer);
1272 refname = refname_buffer;
8da19775
JH
1273 if (flag)
1274 *flag |= REF_ISSYMREF;
a876ed83
JH
1275 continue;
1276 }
ca8db142 1277 }
a876ed83 1278
7a21632f
DS
1279 /* Is it a directory? */
1280 if (S_ISDIR(st.st_mode)) {
1281 errno = EISDIR;
1282 return NULL;
1283 }
1284
a876ed83
JH
1285 /*
1286 * Anything else, just open it and try to use it as
1287 * a ref
1288 */
1289 fd = open(path, O_RDONLY);
1290 if (fd < 0)
1291 return NULL;
93d26e4c 1292 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1293 close(fd);
28775050
MH
1294 if (len < 0)
1295 return NULL;
1296 while (len && isspace(buffer[len-1]))
1297 len--;
1298 buffer[len] = '\0';
a876ed83
JH
1299
1300 /*
1301 * Is it a symbolic ref?
1302 */
28775050 1303 if (prefixcmp(buffer, "ref:"))
a876ed83 1304 break;
55956350
JH
1305 if (flag)
1306 *flag |= REF_ISSYMREF;
a876ed83 1307 buf = buffer + 4;
28775050
MH
1308 while (isspace(*buf))
1309 buf++;
313fb010 1310 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1311 if (flag)
1312 *flag |= REF_ISBROKEN;
313fb010
MH
1313 return NULL;
1314 }
dfefa935 1315 refname = strcpy(refname_buffer, buf);
8a65ff76 1316 }
f989fea0
MH
1317 /* Please note that FETCH_HEAD has a second line containing other data. */
1318 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1319 if (flag)
1320 *flag |= REF_ISBROKEN;
a876ed83 1321 return NULL;
629cd3ac 1322 }
dfefa935 1323 return refname;
a876ed83
JH
1324}
1325
96ec7b1e
NTND
1326char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1327{
8cad4744 1328 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1329 return ret ? xstrdup(ret) : NULL;
1330}
1331
d08bae7e
IL
1332/* The argument to filter_refs */
1333struct ref_filter {
1334 const char *pattern;
1335 each_ref_fn *fn;
1336 void *cb_data;
1337};
1338
dfefa935 1339int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1340{
8d68493f 1341 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1342 return 0;
1343 return -1;
8a65ff76
LT
1344}
1345
dfefa935 1346int read_ref(const char *refname, unsigned char *sha1)
c6893323 1347{
dfefa935 1348 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1349}
1350
bc5fd6d3 1351int ref_exists(const char *refname)
ef06b918 1352{
bc5fd6d3
MH
1353 unsigned char sha1[20];
1354 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1355}
1356
85be1fe3 1357static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1358 void *data)
d08bae7e
IL
1359{
1360 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1361 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1362 return 0;
85be1fe3 1363 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1364}
1365
68cf8703
MH
1366enum peel_status {
1367 /* object was peeled successfully: */
1368 PEEL_PEELED = 0,
1369
1370 /*
1371 * object cannot be peeled because the named object (or an
1372 * object referred to by a tag in the peel chain), does not
1373 * exist.
1374 */
1375 PEEL_INVALID = -1,
1376
1377 /* object cannot be peeled because it is not a tag: */
9a489f3c
MH
1378 PEEL_NON_TAG = -2,
1379
1380 /* ref_entry contains no peeled value because it is a symref: */
1381 PEEL_IS_SYMREF = -3,
1382
1383 /*
1384 * ref_entry cannot be peeled because it is broken (i.e., the
1385 * symbolic reference cannot even be resolved to an object
1386 * name):
1387 */
1388 PEEL_BROKEN = -4
68cf8703
MH
1389};
1390
cb2ae1c4
MH
1391/*
1392 * Peel the named object; i.e., if the object is a tag, resolve the
68cf8703
MH
1393 * tag recursively until a non-tag is found. If successful, store the
1394 * result to sha1 and return PEEL_PEELED. If the object is not a tag
1395 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
1396 * and leave sha1 unchanged.
cb2ae1c4 1397 */
68cf8703 1398static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
cb2ae1c4
MH
1399{
1400 struct object *o = lookup_unknown_object(name);
1401
1402 if (o->type == OBJ_NONE) {
1403 int type = sha1_object_info(name, NULL);
1404 if (type < 0)
68cf8703 1405 return PEEL_INVALID;
cb2ae1c4
MH
1406 o->type = type;
1407 }
1408
1409 if (o->type != OBJ_TAG)
68cf8703 1410 return PEEL_NON_TAG;
cb2ae1c4
MH
1411
1412 o = deref_tag_noverify(o);
1413 if (!o)
68cf8703 1414 return PEEL_INVALID;
cb2ae1c4
MH
1415
1416 hashcpy(sha1, o->sha1);
68cf8703 1417 return PEEL_PEELED;
cb2ae1c4
MH
1418}
1419
9a489f3c 1420/*
f85354b5
MH
1421 * Peel the entry (if possible) and return its new peel_status. If
1422 * repeel is true, re-peel the entry even if there is an old peeled
1423 * value that is already stored in it.
694b7a19
MH
1424 *
1425 * It is OK to call this function with a packed reference entry that
1426 * might be stale and might even refer to an object that has since
1427 * been garbage-collected. In such a case, if the entry has
1428 * REF_KNOWS_PEELED then leave the status unchanged and return
1429 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.
9a489f3c 1430 */
f85354b5 1431static enum peel_status peel_entry(struct ref_entry *entry, int repeel)
9a489f3c
MH
1432{
1433 enum peel_status status;
1434
f85354b5
MH
1435 if (entry->flag & REF_KNOWS_PEELED) {
1436 if (repeel) {
1437 entry->flag &= ~REF_KNOWS_PEELED;
1438 hashclr(entry->u.value.peeled);
1439 } else {
1440 return is_null_sha1(entry->u.value.peeled) ?
1441 PEEL_NON_TAG : PEEL_PEELED;
1442 }
1443 }
9a489f3c
MH
1444 if (entry->flag & REF_ISBROKEN)
1445 return PEEL_BROKEN;
1446 if (entry->flag & REF_ISSYMREF)
1447 return PEEL_IS_SYMREF;
1448
1449 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);
1450 if (status == PEEL_PEELED || status == PEEL_NON_TAG)
1451 entry->flag |= REF_KNOWS_PEELED;
1452 return status;
1453}
1454
dfefa935 1455int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1456{
1457 int flag;
1458 unsigned char base[20];
cf0adba7 1459
dfefa935 1460 if (current_ref && (current_ref->name == refname
9a489f3c 1461 || !strcmp(current_ref->name, refname))) {
f85354b5 1462 if (peel_entry(current_ref, 0))
9a489f3c
MH
1463 return -1;
1464 hashcpy(sha1, current_ref->u.value.peeled);
1465 return 0;
0ae91be0
SP
1466 }
1467
dfefa935 1468 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1469 return -1;
1470
9a489f3c
MH
1471 /*
1472 * If the reference is packed, read its ref_entry from the
1473 * cache in the hope that we already know its peeled value.
1474 * We only try this optimization on packed references because
1475 * (a) forcing the filling of the loose reference cache could
1476 * be expensive and (b) loose references anyway usually do not
1477 * have REF_KNOWS_PEELED.
1478 */
1479 if (flag & REF_ISPACKED) {
f361baeb 1480 struct ref_entry *r = get_packed_ref(refname);
9a489f3c 1481 if (r) {
f85354b5 1482 if (peel_entry(r, 0))
9a489f3c 1483 return -1;
593f1bb8 1484 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1485 return 0;
cf0adba7 1486 }
cf0adba7
JH
1487 }
1488
cb2ae1c4 1489 return peel_object(base, sha1);
cf0adba7
JH
1490}
1491
bc5fd6d3
MH
1492struct warn_if_dangling_data {
1493 FILE *fp;
1494 const char *refname;
1495 const char *msg_fmt;
1496};
1497
1498static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1499 int flags, void *cb_data)
1500{
1501 struct warn_if_dangling_data *d = cb_data;
1502 const char *resolves_to;
1503 unsigned char junk[20];
1504
1505 if (!(flags & REF_ISSYMREF))
1506 return 0;
1507
1508 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1509 if (!resolves_to || strcmp(resolves_to, d->refname))
1510 return 0;
1511
1512 fprintf(d->fp, d->msg_fmt, refname);
1be65eda 1513 fputc('\n', d->fp);
bc5fd6d3
MH
1514 return 0;
1515}
1516
1517void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1518{
1519 struct warn_if_dangling_data data;
1520
1521 data.fp = fp;
1522 data.refname = refname;
1523 data.msg_fmt = msg_fmt;
1524 for_each_rawref(warn_if_dangling_symref, &data);
1525}
1526
fcce1703 1527/*
65cf102b 1528 * Call fn for each reference in the specified ref_cache, omitting
624cac35
MH
1529 * references not in the containing_dir of base. fn is called for all
1530 * references, including broken ones. If fn ever returns a non-zero
fcce1703
MH
1531 * value, stop the iteration and return that value; otherwise, return
1532 * 0.
1533 */
65cf102b 1534static int do_for_each_entry(struct ref_cache *refs, const char *base,
624cac35 1535 each_ref_entry_fn fn, void *cb_data)
8a65ff76 1536{
933ac036
MH
1537 struct ref_dir *packed_dir = get_packed_refs(refs);
1538 struct ref_dir *loose_dir = get_loose_refs(refs);
1539 int retval = 0;
1540
1541 if (base && *base) {
1542 packed_dir = find_containing_dir(packed_dir, base, 0);
1543 loose_dir = find_containing_dir(loose_dir, base, 0);
1544 }
1545
1546 if (packed_dir && loose_dir) {
1547 sort_ref_dir(packed_dir);
1548 sort_ref_dir(loose_dir);
624cac35
MH
1549 retval = do_for_each_entry_in_dirs(
1550 packed_dir, loose_dir, fn, cb_data);
933ac036
MH
1551 } else if (packed_dir) {
1552 sort_ref_dir(packed_dir);
624cac35
MH
1553 retval = do_for_each_entry_in_dir(
1554 packed_dir, 0, fn, cb_data);
933ac036
MH
1555 } else if (loose_dir) {
1556 sort_ref_dir(loose_dir);
624cac35
MH
1557 retval = do_for_each_entry_in_dir(
1558 loose_dir, 0, fn, cb_data);
933ac036
MH
1559 }
1560
1561 return retval;
8a65ff76
LT
1562}
1563
624cac35 1564/*
65cf102b 1565 * Call fn for each reference in the specified ref_cache for which the
624cac35
MH
1566 * refname begins with base. If trim is non-zero, then trim that many
1567 * characters off the beginning of each refname before passing the
1568 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include
1569 * broken references in the iteration. If fn ever returns a non-zero
1570 * value, stop the iteration and return that value; otherwise, return
1571 * 0.
1572 */
65cf102b
MH
1573static int do_for_each_ref(struct ref_cache *refs, const char *base,
1574 each_ref_fn fn, int trim, int flags, void *cb_data)
624cac35
MH
1575{
1576 struct ref_entry_cb data;
1577 data.base = base;
1578 data.trim = trim;
1579 data.flags = flags;
1580 data.fn = fn;
1581 data.cb_data = cb_data;
1582
65cf102b 1583 return do_for_each_entry(refs, base, do_one_ref, &data);
624cac35
MH
1584}
1585
0bad611b 1586static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1587{
1588 unsigned char sha1[20];
8da19775
JH
1589 int flag;
1590
0bad611b
HV
1591 if (submodule) {
1592 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1593 return fn("HEAD", sha1, 0, cb_data);
1594
1595 return 0;
1596 }
1597
c6893323 1598 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1599 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1600
2f34ba32 1601 return 0;
723c31fe
LT
1602}
1603
0bad611b
HV
1604int head_ref(each_ref_fn fn, void *cb_data)
1605{
1606 return do_head_ref(NULL, fn, cb_data);
1607}
1608
9ef6aeb0
HV
1609int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1610{
1611 return do_head_ref(submodule, fn, cb_data);
1612}
1613
cb5d709f 1614int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1615{
9da31cb0 1616 return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);
a62be77f
SE
1617}
1618
9ef6aeb0
HV
1619int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1620{
65cf102b 1621 return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data);
a62be77f
SE
1622}
1623
2a8177b6
CC
1624int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1625{
9da31cb0 1626 return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1627}
1628
9ef6aeb0
HV
1629int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1630 each_ref_fn fn, void *cb_data)
1631{
65cf102b 1632 return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1633}
1634
cb5d709f 1635int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1636{
2a8177b6 1637 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1638}
1639
9ef6aeb0
HV
1640int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1641{
1642 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1643}
1644
cb5d709f 1645int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1646{
2a8177b6 1647 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1648}
1649
9ef6aeb0
HV
1650int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1651{
1652 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1653}
1654
cb5d709f 1655int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1656{
2a8177b6 1657 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1658}
1659
9ef6aeb0
HV
1660int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1661{
1662 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1663}
1664
29268700
CC
1665int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1666{
9da31cb0 1667 return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1668}
1669
a1bea2c1
JT
1670int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1671{
1672 struct strbuf buf = STRBUF_INIT;
1673 int ret = 0;
1674 unsigned char sha1[20];
1675 int flag;
1676
1677 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1678 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1679 ret = fn(buf.buf, sha1, flag, cb_data);
1680 strbuf_release(&buf);
1681
1682 return ret;
1683}
1684
1685int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1686{
1687 struct strbuf buf = STRBUF_INIT;
1688 int ret;
1689 strbuf_addf(&buf, "%srefs/", get_git_namespace());
9da31cb0 1690 ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);
a1bea2c1
JT
1691 strbuf_release(&buf);
1692 return ret;
1693}
1694
b09fe971
IL
1695int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1696 const char *prefix, void *cb_data)
d08bae7e
IL
1697{
1698 struct strbuf real_pattern = STRBUF_INIT;
1699 struct ref_filter filter;
d08bae7e
IL
1700 int ret;
1701
b09fe971 1702 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1703 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1704 else if (prefix)
1705 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1706 strbuf_addstr(&real_pattern, pattern);
1707
894a9d33 1708 if (!has_glob_specials(pattern)) {
9517e6b8 1709 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1710 if (real_pattern.buf[real_pattern.len - 1] != '/')
1711 strbuf_addch(&real_pattern, '/');
1712 /* No need to check for '*', there is none. */
1713 strbuf_addch(&real_pattern, '*');
1714 }
1715
1716 filter.pattern = real_pattern.buf;
1717 filter.fn = fn;
1718 filter.cb_data = cb_data;
1719 ret = for_each_ref(filter_refs, &filter);
1720
1721 strbuf_release(&real_pattern);
1722 return ret;
1723}
1724
b09fe971
IL
1725int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1726{
1727 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1728}
1729
f8948e2f
JH
1730int for_each_rawref(each_ref_fn fn, void *cb_data)
1731{
9da31cb0 1732 return do_for_each_ref(&ref_cache, "", fn, 0,
f8948e2f 1733 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1734}
1735
4577e483 1736const char *prettify_refname(const char *name)
a9c37a72 1737{
a9c37a72
DB
1738 return name + (
1739 !prefixcmp(name, "refs/heads/") ? 11 :
1740 !prefixcmp(name, "refs/tags/") ? 10 :
1741 !prefixcmp(name, "refs/remotes/") ? 13 :
1742 0);
1743}
1744
79803322
SP
1745const char *ref_rev_parse_rules[] = {
1746 "%.*s",
1747 "refs/%.*s",
1748 "refs/tags/%.*s",
1749 "refs/heads/%.*s",
1750 "refs/remotes/%.*s",
1751 "refs/remotes/%.*s/HEAD",
1752 NULL
1753};
1754
1755int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1756{
1757 const char **p;
1758 const int abbrev_name_len = strlen(abbrev_name);
1759
1760 for (p = rules; *p; p++) {
1761 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1762 return 1;
1763 }
1764 }
1765
1766 return 0;
1767}
1768
e5f38ec3 1769static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1770 const unsigned char *old_sha1, int mustexist)
1771{
c6893323 1772 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1773 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1774 unlock_ref(lock);
1775 return NULL;
1776 }
a89fccd2 1777 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1778 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1779 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1780 unlock_ref(lock);
1781 return NULL;
1782 }
1783 return lock;
1784}
1785
7155b727 1786static int remove_empty_directories(const char *file)
bc7127ef
JH
1787{
1788 /* we want to create a file but there is a directory there;
1789 * if that is an empty directory (or a directory that contains
1790 * only empty directories), remove them.
1791 */
7155b727
JS
1792 struct strbuf path;
1793 int result;
bc7127ef 1794
7155b727
JS
1795 strbuf_init(&path, 20);
1796 strbuf_addstr(&path, file);
1797
a0f4afbe 1798 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1799
1800 strbuf_release(&path);
1801
1802 return result;
bc7127ef
JH
1803}
1804
ff74f7f1
JH
1805/*
1806 * *string and *len will only be substituted, and *string returned (for
1807 * later free()ing) if the string passed in is a magic short-hand form
1808 * to name a branch.
1809 */
1810static char *substitute_branch_name(const char **string, int *len)
1811{
1812 struct strbuf buf = STRBUF_INIT;
1813 int ret = interpret_branch_name(*string, &buf);
1814
1815 if (ret == *len) {
1816 size_t size;
1817 *string = strbuf_detach(&buf, &size);
1818 *len = size;
1819 return (char *)*string;
1820 }
1821
1822 return NULL;
1823}
1824
1825int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1826{
1827 char *last_branch = substitute_branch_name(&str, &len);
1828 const char **p, *r;
1829 int refs_found = 0;
1830
1831 *ref = NULL;
1832 for (p = ref_rev_parse_rules; *p; p++) {
1833 char fullref[PATH_MAX];
1834 unsigned char sha1_from_ref[20];
1835 unsigned char *this_result;
1836 int flag;
1837
1838 this_result = refs_found ? sha1_from_ref : sha1;
1839 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1840 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1841 if (r) {
1842 if (!refs_found++)
1843 *ref = xstrdup(r);
1844 if (!warn_ambiguous_refs)
1845 break;
55956350 1846 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1847 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1848 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1849 warning("ignoring broken ref %s.", fullref);
1850 }
ff74f7f1
JH
1851 }
1852 free(last_branch);
1853 return refs_found;
1854}
1855
1856int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1857{
1858 char *last_branch = substitute_branch_name(&str, &len);
1859 const char **p;
1860 int logs_found = 0;
1861
1862 *log = NULL;
1863 for (p = ref_rev_parse_rules; *p; p++) {
1864 struct stat st;
1865 unsigned char hash[20];
1866 char path[PATH_MAX];
1867 const char *ref, *it;
1868
1869 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1870 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1871 if (!ref)
1872 continue;
1873 if (!stat(git_path("logs/%s", path), &st) &&
1874 S_ISREG(st.st_mode))
1875 it = path;
1876 else if (strcmp(ref, path) &&
1877 !stat(git_path("logs/%s", ref), &st) &&
1878 S_ISREG(st.st_mode))
1879 it = ref;
1880 else
1881 continue;
1882 if (!logs_found++) {
1883 *log = xstrdup(it);
1884 hashcpy(sha1, hash);
1885 }
1886 if (!warn_ambiguous_refs)
1887 break;
1888 }
1889 free(last_branch);
1890 return logs_found;
1891}
1892
dfefa935
MH
1893static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1894 const unsigned char *old_sha1,
1895 int flags, int *type_p)
4bd18c43 1896{
434cd0cd 1897 char *ref_file;
dfefa935 1898 const char *orig_refname = refname;
4bd18c43 1899 struct ref_lock *lock;
5cc3cef9 1900 int last_errno = 0;
acd3b9ec 1901 int type, lflags;
4431fcc4 1902 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1903 int missing = 0;
4bd18c43
SP
1904
1905 lock = xcalloc(1, sizeof(struct ref_lock));
1906 lock->lock_fd = -1;
1907
8d68493f 1908 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1909 if (!refname && errno == EISDIR) {
bc7127ef
JH
1910 /* we are trying to lock foo but we used to
1911 * have foo/bar which now does not exist;
1912 * it is normal for the empty directory 'foo'
1913 * to remain.
1914 */
dfefa935 1915 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1916 if (remove_empty_directories(ref_file)) {
1917 last_errno = errno;
dfefa935 1918 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1919 goto error_return;
1920 }
8d68493f 1921 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1922 }
68db31cc
SV
1923 if (type_p)
1924 *type_p = type;
dfefa935 1925 if (!refname) {
5cc3cef9 1926 last_errno = errno;
818f477c 1927 error("unable to resolve reference %s: %s",
dfefa935 1928 orig_refname, strerror(errno));
5cc3cef9 1929 goto error_return;
4bd18c43 1930 }
5bdd8d4a 1931 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1932 /* When the ref did not exist and we are creating it,
1933 * make sure there is no existing ref that is packed
1934 * whose name begins with our refname, nor a ref whose
1935 * name is a proper prefix of our refname.
1936 */
5bdd8d4a 1937 if (missing &&
9da31cb0 1938 !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {
f475e08e 1939 last_errno = ENOTDIR;
c976d415 1940 goto error_return;
f475e08e 1941 }
22a3844e 1942
c33d5174 1943 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1944
acd3b9ec
JH
1945 lflags = LOCK_DIE_ON_ERROR;
1946 if (flags & REF_NODEREF) {
dfefa935 1947 refname = orig_refname;
acd3b9ec
JH
1948 lflags |= LOCK_NODEREF;
1949 }
dfefa935
MH
1950 lock->ref_name = xstrdup(refname);
1951 lock->orig_ref_name = xstrdup(orig_refname);
1952 ref_file = git_path("%s", refname);
5bdd8d4a 1953 if (missing)
68db31cc
SV
1954 lock->force_write = 1;
1955 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1956 lock->force_write = 1;
4bd18c43 1957
5cc3cef9
JH
1958 if (safe_create_leading_directories(ref_file)) {
1959 last_errno = errno;
1960 error("unable to create directory for %s", ref_file);
1961 goto error_return;
1962 }
4bd18c43 1963
acd3b9ec 1964 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1965 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1966
1967 error_return:
1968 unlock_ref(lock);
1969 errno = last_errno;
1970 return NULL;
4bd18c43
SP
1971}
1972
dfefa935 1973struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1974{
53cce84c 1975 char refpath[PATH_MAX];
dfefa935 1976 if (check_refname_format(refname, 0))
4bd18c43 1977 return NULL;
dfefa935 1978 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1979 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1980}
1981
dfefa935
MH
1982struct ref_lock *lock_any_ref_for_update(const char *refname,
1983 const unsigned char *old_sha1, int flags)
4bd18c43 1984{
dfefa935 1985 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1986 return NULL;
dfefa935 1987 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1988}
1989
fec3137f
MH
1990/*
1991 * Write an entry to the packed-refs file for the specified refname.
1992 * If peeled is non-NULL, write it as the entry's peeled value.
1993 */
1994static void write_packed_entry(int fd, char *refname, unsigned char *sha1,
1995 unsigned char *peeled)
d66da478 1996{
d66da478
MH
1997 char line[PATH_MAX + 100];
1998 int len;
1999
d66da478
MH
2000 len = snprintf(line, sizeof(line), "%s %s\n",
2001 sha1_to_hex(sha1), refname);
2002 /* this should not happen but just being defensive */
2003 if (len > sizeof(line))
2004 die("too long a refname '%s'", refname);
fec3137f
MH
2005 write_or_die(fd, line, len);
2006
2007 if (peeled) {
2008 if (snprintf(line, sizeof(line), "^%s\n",
2009 sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)
2010 die("internal error");
2011 write_or_die(fd, line, PEELED_LINE_LENGTH);
2012 }
2013}
2014
32d462ce
MH
2015struct ref_to_prune {
2016 struct ref_to_prune *next;
2017 unsigned char sha1[20];
2018 char name[FLEX_ARRAY];
2019};
2020
2021struct pack_refs_cb_data {
2022 unsigned int flags;
2023 struct ref_to_prune *ref_to_prune;
0f29920f 2024 int fd;
32d462ce
MH
2025};
2026
12e77559 2027static int pack_one_ref(struct ref_entry *entry, void *cb_data)
32d462ce
MH
2028{
2029 struct pack_refs_cb_data *cb = cb_data;
f85354b5 2030 enum peel_status peel_status;
b2a8226d 2031 int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");
32d462ce
MH
2032
2033 /* ALWAYS pack refs that were already packed or are tags */
12e77559
MH
2034 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref &&
2035 !(entry->flag & REF_ISPACKED))
32d462ce
MH
2036 return 0;
2037
b2a8226d
MH
2038 /* Do not pack symbolic or broken refs: */
2039 if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))
2040 return 0;
2041
f85354b5 2042 peel_status = peel_entry(entry, 1);
0f29920f 2043 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
f85354b5
MH
2044 die("internal error peeling reference %s (%s)",
2045 entry->name, sha1_to_hex(entry->u.value.sha1));
0f29920f
MH
2046 write_packed_entry(cb->fd, entry->name, entry->u.value.sha1,
2047 peel_status == PEEL_PEELED ?
2048 entry->u.value.peeled : NULL);
32d462ce 2049
8d3725b9
MH
2050 /* If the ref was already packed, there is no need to prune it. */
2051 if ((cb->flags & PACK_REFS_PRUNE) && !(entry->flag & REF_ISPACKED)) {
12e77559 2052 int namelen = strlen(entry->name) + 1;
32d462ce 2053 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
12e77559
MH
2054 hashcpy(n->sha1, entry->u.value.sha1);
2055 strcpy(n->name, entry->name);
32d462ce
MH
2056 n->next = cb->ref_to_prune;
2057 cb->ref_to_prune = n;
2058 }
d66da478
MH
2059 return 0;
2060}
2061
32d462ce
MH
2062/*
2063 * Remove empty parents, but spare refs/ and immediate subdirs.
2064 * Note: munges *name.
2065 */
2066static void try_remove_empty_parents(char *name)
2067{
2068 char *p, *q;
2069 int i;
2070 p = name;
2071 for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */
2072 while (*p && *p != '/')
2073 p++;
2074 /* tolerate duplicate slashes; see check_refname_format() */
2075 while (*p == '/')
2076 p++;
2077 }
2078 for (q = p; *q; q++)
2079 ;
2080 while (1) {
2081 while (q > p && *q != '/')
2082 q--;
2083 while (q > p && *(q-1) == '/')
2084 q--;
2085 if (q == p)
2086 break;
2087 *q = '\0';
2088 if (rmdir(git_path("%s", name)))
2089 break;
2090 }
2091}
2092
2093/* make sure nobody touched the ref, and unlink */
2094static void prune_ref(struct ref_to_prune *r)
2095{
2096 struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
2097
2098 if (lock) {
2099 unlink_or_warn(git_path("%s", r->name));
2100 unlock_ref(lock);
2101 try_remove_empty_parents(r->name);
2102 }
2103}
2104
2105static void prune_refs(struct ref_to_prune *r)
2106{
2107 while (r) {
2108 prune_ref(r);
2109 r = r->next;
2110 }
2111}
2112
26a063a1
JH
2113static struct lock_file packlock;
2114
32d462ce
MH
2115int pack_refs(unsigned int flags)
2116{
32d462ce
MH
2117 struct pack_refs_cb_data cbdata;
2118
2119 memset(&cbdata, 0, sizeof(cbdata));
2120 cbdata.flags = flags;
2121
0f29920f
MH
2122 cbdata.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"),
2123 LOCK_DIE_ON_ERROR);
32d462ce 2124
0f29920f 2125 write_or_die(cbdata.fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
32d462ce 2126
9da31cb0 2127 do_for_each_entry(&ref_cache, "", pack_one_ref, &cbdata);
d9470330 2128 if (commit_lock_file(&packlock) < 0)
32d462ce
MH
2129 die_errno("unable to overwrite old ref-pack file");
2130 prune_refs(cbdata.ref_to_prune);
2131 return 0;
2132}
2133
fec3137f 2134static int repack_ref_fn(struct ref_entry *entry, void *cb_data)
c0277d15 2135{
fec3137f
MH
2136 int *fd = cb_data;
2137 enum peel_status peel_status;
2138
ab292bc4
MH
2139 if (entry->flag & REF_ISBROKEN) {
2140 /* This shouldn't happen to packed refs. */
2141 error("%s is broken!", entry->name);
c0277d15 2142 return 0;
ab292bc4
MH
2143 }
2144 if (!has_sha1_file(entry->u.value.sha1)) {
2145 unsigned char sha1[20];
2146 int flags;
2147
2148 if (read_ref_full(entry->name, sha1, 0, &flags))
2149 /* We should at least have found the packed ref. */
2150 die("Internal error");
2151 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED))
2152 /*
2153 * This packed reference is overridden by a
2154 * loose reference, so it is OK that its value
2155 * is no longer valid; for example, it might
2156 * refer to an object that has been garbage
2157 * collected. For this purpose we don't even
2158 * care whether the loose reference itself is
2159 * invalid, broken, symbolic, etc. Silently
2160 * omit the packed reference from the output.
2161 */
2162 return 0;
2163 /*
2164 * There is no overriding loose reference, so the fact
2165 * that this reference doesn't refer to a valid object
2166 * indicates some kind of repository corruption.
2167 * Report the problem, then omit the reference from
2168 * the output.
2169 */
2170 error("%s does not point to a valid object!", entry->name);
2171 return 0;
2172 }
2173
f85354b5 2174 peel_status = peel_entry(entry, 0);
fec3137f
MH
2175 write_packed_entry(*fd, entry->name, entry->u.value.sha1,
2176 peel_status == PEEL_PEELED ?
2177 entry->u.value.peeled : NULL);
694b7a19 2178
d66da478
MH
2179 return 0;
2180}
2181
c0277d15
JH
2182static int repack_without_ref(const char *refname)
2183{
506a760d 2184 int fd;
7618fd80
MH
2185 struct ref_dir *packed;
2186
2187 if (!get_packed_ref(refname))
2188 return 0; /* refname does not exist in packed refs */
2189
506a760d
MH
2190 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
2191 if (fd < 0) {
1b018fd9 2192 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 2193 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 2194 }
9da31cb0
MH
2195 clear_packed_ref_cache(&ref_cache);
2196 packed = get_packed_refs(&ref_cache);
506a760d
MH
2197 /* Remove refname from the cache. */
2198 if (remove_entry(packed, refname) == -1) {
2199 /*
2200 * The packed entry disappeared while we were
2201 * acquiring the lock.
2202 */
2203 rollback_lock_file(&packlock);
2204 return 0;
2205 }
694b7a19 2206 write_or_die(fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
506a760d 2207 do_for_each_entry_in_dir(packed, 0, repack_ref_fn, &fd);
c0277d15
JH
2208 return commit_lock_file(&packlock);
2209}
2210
eca35a25 2211int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
2212{
2213 struct ref_lock *lock;
eca35a25 2214 int err, i = 0, ret = 0, flag = 0;
c0277d15 2215
547d058f 2216 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
c0277d15
JH
2217 if (!lock)
2218 return 1;
045a476f 2219 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 2220 /* loose */
547d058f
RS
2221 i = strlen(lock->lk->filename) - 5; /* .lock */
2222 lock->lk->filename[i] = 0;
2223 err = unlink_or_warn(lock->lk->filename);
691f1a28 2224 if (err && errno != ENOENT)
c0277d15 2225 ret = 1;
691f1a28 2226
547d058f 2227 lock->lk->filename[i] = '.';
c0277d15
JH
2228 }
2229 /* removing the loose one could have resurrected an earlier
2230 * packed one. Also, if it was not loose we need to repack
2231 * without it.
2232 */
b274a714 2233 ret |= repack_without_ref(lock->ref_name);
c0277d15 2234
691f1a28 2235 unlink_or_warn(git_path("logs/%s", lock->ref_name));
9da31cb0 2236 clear_loose_ref_cache(&ref_cache);
c0277d15
JH
2237 unlock_ref(lock);
2238 return ret;
4bd18c43
SP
2239}
2240
765c2258
PH
2241/*
2242 * People using contrib's git-new-workdir have .git/logs/refs ->
2243 * /some/other/path/.git/logs/refs, and that may live on another device.
2244 *
2245 * IOW, to avoid cross device rename errors, the temporary renamed log must
2246 * live into logs/refs.
2247 */
2248#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
2249
dfefa935 2250int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 2251{
c976d415
LH
2252 unsigned char sha1[20], orig_sha1[20];
2253 int flag = 0, logmoved = 0;
2254 struct ref_lock *lock;
c976d415 2255 struct stat loginfo;
dfefa935 2256 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 2257 const char *symref = NULL;
c976d415 2258
450d4c0f 2259 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 2260 return error("reflog for %s is a symlink", oldrefname);
c976d415 2261
8d68493f 2262 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 2263 if (flag & REF_ISSYMREF)
fa58186c 2264 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 2265 oldrefname);
eca35a25 2266 if (!symref)
dfefa935 2267 return error("refname %s not found", oldrefname);
c976d415 2268
9da31cb0 2269 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))
c976d415
LH
2270 return 1;
2271
9da31cb0 2272 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))
c976d415
LH
2273 return 1;
2274
dfefa935 2275 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 2276 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 2277 oldrefname, strerror(errno));
c976d415 2278
dfefa935
MH
2279 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
2280 error("unable to delete old %s", oldrefname);
c976d415
LH
2281 goto rollback;
2282 }
2283
dfefa935
MH
2284 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
2285 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 2286 if (errno==EISDIR) {
dfefa935
MH
2287 if (remove_empty_directories(git_path("%s", newrefname))) {
2288 error("Directory not empty: %s", newrefname);
c976d415
LH
2289 goto rollback;
2290 }
2291 } else {
dfefa935 2292 error("unable to delete existing %s", newrefname);
c976d415
LH
2293 goto rollback;
2294 }
2295 }
2296
dfefa935
MH
2297 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
2298 error("unable to create directory for %s", newrefname);
c976d415
LH
2299 goto rollback;
2300 }
2301
2302 retry:
dfefa935 2303 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
2304 if (errno==EISDIR || errno==ENOTDIR) {
2305 /*
2306 * rename(a, b) when b is an existing
2307 * directory ought to result in ISDIR, but
2308 * Solaris 5.8 gives ENOTDIR. Sheesh.
2309 */
dfefa935
MH
2310 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
2311 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
2312 goto rollback;
2313 }
2314 goto retry;
2315 } else {
765c2258 2316 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 2317 newrefname, strerror(errno));
c976d415
LH
2318 goto rollback;
2319 }
2320 }
2321 logmoved = log;
2322
dfefa935 2323 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 2324 if (!lock) {
dfefa935 2325 error("unable to lock %s for update", newrefname);
c976d415
LH
2326 goto rollback;
2327 }
c976d415
LH
2328 lock->force_write = 1;
2329 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 2330 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 2331 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
2332 goto rollback;
2333 }
2334
2335 return 0;
2336
2337 rollback:
dfefa935 2338 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 2339 if (!lock) {
dfefa935 2340 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
2341 goto rollbacklog;
2342 }
2343
2344 lock->force_write = 1;
2345 flag = log_all_ref_updates;
2346 log_all_ref_updates = 0;
2347 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 2348 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
2349 log_all_ref_updates = flag;
2350
2351 rollbacklog:
dfefa935 2352 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 2353 error("unable to restore logfile %s from %s: %s",
dfefa935 2354 oldrefname, newrefname, strerror(errno));
c976d415 2355 if (!logmoved && log &&
dfefa935 2356 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 2357 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 2358 oldrefname, strerror(errno));
c976d415
LH
2359
2360 return 1;
2361}
2362
435fc852 2363int close_ref(struct ref_lock *lock)
b531394d
BC
2364{
2365 if (close_lock_file(lock->lk))
2366 return -1;
2367 lock->lock_fd = -1;
2368 return 0;
2369}
2370
435fc852 2371int commit_ref(struct ref_lock *lock)
b531394d
BC
2372{
2373 if (commit_lock_file(lock->lk))
2374 return -1;
2375 lock->lock_fd = -1;
2376 return 0;
2377}
2378
e5f38ec3 2379void unlock_ref(struct ref_lock *lock)
4bd18c43 2380{
4ed7cd3a
BC
2381 /* Do not free lock->lk -- atexit() still looks at them */
2382 if (lock->lk)
2383 rollback_lock_file(lock->lk);
434cd0cd 2384 free(lock->ref_name);
1655707c 2385 free(lock->orig_ref_name);
4bd18c43
SP
2386 free(lock);
2387}
2388
0ec29a47
JH
2389/*
2390 * copy the reflog message msg to buf, which has been allocated sufficiently
2391 * large, while cleaning up the whitespaces. Especially, convert LF to space,
2392 * because reflog file is one line per entry.
2393 */
2394static int copy_msg(char *buf, const char *msg)
2395{
2396 char *cp = buf;
2397 char c;
2398 int wasspace = 1;
2399
2400 *cp++ = '\t';
2401 while ((c = *msg++)) {
2402 if (wasspace && isspace(c))
2403 continue;
2404 wasspace = isspace(c);
2405 if (wasspace)
2406 c = ' ';
2407 *cp++ = c;
2408 }
2409 while (buf < cp && isspace(cp[-1]))
2410 cp--;
2411 *cp++ = '\n';
2412 return cp - buf;
2413}
2414
dfefa935 2415int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 2416{
859c3017 2417 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 2418
dfefa935 2419 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 2420 if (log_all_ref_updates &&
dfefa935
MH
2421 (!prefixcmp(refname, "refs/heads/") ||
2422 !prefixcmp(refname, "refs/remotes/") ||
2423 !prefixcmp(refname, "refs/notes/") ||
2424 !strcmp(refname, "HEAD"))) {
157aaea5 2425 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 2426 return error("unable to create directory for %s",
157aaea5 2427 logfile);
6de08ae6
SP
2428 oflags |= O_CREAT;
2429 }
2430
157aaea5 2431 logfd = open(logfile, oflags, 0666);
6de08ae6 2432 if (logfd < 0) {
1974bf62 2433 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 2434 return 0;
3b463c3f
JH
2435
2436 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 2437 if (remove_empty_directories(logfile)) {
3b463c3f 2438 return error("There are still logs under '%s'",
157aaea5 2439 logfile);
3b463c3f 2440 }
157aaea5 2441 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
2442 }
2443
2444 if (logfd < 0)
2445 return error("Unable to append to %s: %s",
157aaea5 2446 logfile, strerror(errno));
6de08ae6
SP
2447 }
2448
157aaea5 2449 adjust_shared_perm(logfile);
859c3017
EM
2450 close(logfd);
2451 return 0;
2452}
443b92b6 2453
dfefa935 2454static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
2455 const unsigned char *new_sha1, const char *msg)
2456{
2457 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2458 unsigned maxlen, len;
2459 int msglen;
157aaea5 2460 char log_file[PATH_MAX];
859c3017
EM
2461 char *logrec;
2462 const char *committer;
2463
2464 if (log_all_ref_updates < 0)
2465 log_all_ref_updates = !is_bare_repository();
2466
dfefa935 2467 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
2468 if (result)
2469 return result;
2470
2471 logfd = open(log_file, oflags);
2472 if (logfd < 0)
2473 return 0;
0ec29a47 2474 msglen = msg ? strlen(msg) : 0;
774751a8 2475 committer = git_committer_info(0);
8ac65937
JH
2476 maxlen = strlen(committer) + msglen + 100;
2477 logrec = xmalloc(maxlen);
2478 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
2479 sha1_to_hex(old_sha1),
2480 sha1_to_hex(new_sha1),
8ac65937
JH
2481 committer);
2482 if (msglen)
0ec29a47 2483 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 2484 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 2485 free(logrec);
91c8d590 2486 if (close(logfd) != 0 || written != len)
9a13f0b7 2487 return error("Unable to append to %s", log_file);
6de08ae6
SP
2488 return 0;
2489}
2490
c3b0dec5
LT
2491static int is_branch(const char *refname)
2492{
2493 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2494}
2495
4bd18c43
SP
2496int write_ref_sha1(struct ref_lock *lock,
2497 const unsigned char *sha1, const char *logmsg)
2498{
2499 static char term = '\n';
c3b0dec5 2500 struct object *o;
4bd18c43
SP
2501
2502 if (!lock)
95fc7512 2503 return -1;
a89fccd2 2504 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
2505 unlock_ref(lock);
2506 return 0;
95fc7512 2507 }
c3b0dec5
LT
2508 o = parse_object(sha1);
2509 if (!o) {
7be8b3ba 2510 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
2511 lock->ref_name, sha1_to_hex(sha1));
2512 unlock_ref(lock);
2513 return -1;
2514 }
2515 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2516 error("Trying to write non-commit object %s to branch %s",
2517 sha1_to_hex(sha1), lock->ref_name);
2518 unlock_ref(lock);
2519 return -1;
2520 }
93822c22
AW
2521 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2522 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 2523 || close_ref(lock) < 0) {
c33d5174 2524 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
2525 unlock_ref(lock);
2526 return -1;
2527 }
9da31cb0 2528 clear_loose_ref_cache(&ref_cache);
bd104db1
NP
2529 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2530 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2531 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
2532 unlock_ref(lock);
2533 return -1;
2534 }
605fac8b
NP
2535 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2536 /*
2537 * Special hack: If a branch is updated directly and HEAD
2538 * points to it (may happen on the remote side of a push
2539 * for example) then logically the HEAD reflog should be
2540 * updated too.
2541 * A generic solution implies reverse symref information,
2542 * but finding all symrefs pointing to the given branch
2543 * would be rather costly for this rare event (the direct
2544 * update of a branch) to be worth it. So let's cheat and
2545 * check with HEAD only which should cover 99% of all usage
2546 * scenarios (even 100% of the default ones).
2547 */
2548 unsigned char head_sha1[20];
2549 int head_flag;
2550 const char *head_ref;
8cad4744 2551 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2552 if (head_ref && (head_flag & REF_ISSYMREF) &&
2553 !strcmp(head_ref, lock->ref_name))
2554 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2555 }
b531394d 2556 if (commit_ref(lock)) {
434cd0cd 2557 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2558 unlock_ref(lock);
2559 return -1;
2560 }
4bd18c43
SP
2561 unlock_ref(lock);
2562 return 0;
95fc7512 2563}
d556fae2 2564
8b5157e4
NP
2565int create_symref(const char *ref_target, const char *refs_heads_master,
2566 const char *logmsg)
41b625b0
NP
2567{
2568 const char *lockpath;
2569 char ref[1000];
2570 int fd, len, written;
a4f34cbb 2571 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2572 unsigned char old_sha1[20], new_sha1[20];
2573
2574 if (logmsg && read_ref(ref_target, old_sha1))
2575 hashclr(old_sha1);
41b625b0 2576
d48744d1
JH
2577 if (safe_create_leading_directories(git_HEAD) < 0)
2578 return error("unable to create directory for %s", git_HEAD);
2579
41b625b0
NP
2580#ifndef NO_SYMLINK_HEAD
2581 if (prefer_symlink_refs) {
2582 unlink(git_HEAD);
2583 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2584 goto done;
41b625b0
NP
2585 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2586 }
2587#endif
2588
2589 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2590 if (sizeof(ref) <= len) {
2591 error("refname too long: %s", refs_heads_master);
47fc52e2 2592 goto error_free_return;
41b625b0
NP
2593 }
2594 lockpath = mkpath("%s.lock", git_HEAD);
2595 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2596 if (fd < 0) {
2597 error("Unable to open %s for writing", lockpath);
47fc52e2 2598 goto error_free_return;
41b625b0
NP
2599 }
2600 written = write_in_full(fd, ref, len);
91c8d590 2601 if (close(fd) != 0 || written != len) {
41b625b0 2602 error("Unable to write to %s", lockpath);
47fc52e2 2603 goto error_unlink_return;
41b625b0
NP
2604 }
2605 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2606 error("Unable to create %s", git_HEAD);
47fc52e2 2607 goto error_unlink_return;
41b625b0
NP
2608 }
2609 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2610 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2611 error_unlink_return:
691f1a28 2612 unlink_or_warn(lockpath);
47fc52e2
JH
2613 error_free_return:
2614 free(git_HEAD);
2615 return -1;
41b625b0 2616 }
8b5157e4 2617
ee96d11b 2618#ifndef NO_SYMLINK_HEAD
8b5157e4 2619 done:
ee96d11b 2620#endif
8b5157e4
NP
2621 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2622 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2623
47fc52e2 2624 free(git_HEAD);
41b625b0
NP
2625 return 0;
2626}
2627
16d7cc90
JH
2628static char *ref_msg(const char *line, const char *endp)
2629{
2630 const char *ep;
16d7cc90 2631 line += 82;
182af834
PH
2632 ep = memchr(line, '\n', endp - line);
2633 if (!ep)
2634 ep = endp;
2635 return xmemdupz(line, ep - line);
16d7cc90
JH
2636}
2637
dfefa935
MH
2638int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2639 unsigned char *sha1, char **msg,
2640 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2641{
e5229042 2642 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2643 char *tz_c;
e29cb53a 2644 int logfd, tz, reccnt = 0;
d556fae2
SP
2645 struct stat st;
2646 unsigned long date;
e5229042 2647 unsigned char logged_sha1[20];
cb48cb58 2648 void *log_mapped;
dc49cd76 2649 size_t mapsz;
d556fae2 2650
dfefa935 2651 logfile = git_path("logs/%s", refname);
d556fae2
SP
2652 logfd = open(logfile, O_RDONLY, 0);
2653 if (logfd < 0)
d824cbba 2654 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2655 fstat(logfd, &st);
2656 if (!st.st_size)
2657 die("Log %s is empty.", logfile);
dc49cd76
SP
2658 mapsz = xsize_t(st.st_size);
2659 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2660 logdata = log_mapped;
d556fae2
SP
2661 close(logfd);
2662
e5229042 2663 lastrec = NULL;
d556fae2
SP
2664 rec = logend = logdata + st.st_size;
2665 while (logdata < rec) {
e29cb53a 2666 reccnt++;
d556fae2
SP
2667 if (logdata < rec && *(rec-1) == '\n')
2668 rec--;
e5229042
SP
2669 lastgt = NULL;
2670 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2671 rec--;
e5229042
SP
2672 if (*rec == '>')
2673 lastgt = rec;
2674 }
2675 if (!lastgt)
d556fae2 2676 die("Log %s is corrupt.", logfile);
e5229042 2677 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2678 if (date <= at_time || cnt == 0) {
76a44c5c 2679 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2680 if (msg)
2681 *msg = ref_msg(rec, logend);
2682 if (cutoff_time)
2683 *cutoff_time = date;
2684 if (cutoff_tz)
2685 *cutoff_tz = tz;
2686 if (cutoff_cnt)
76a44c5c 2687 *cutoff_cnt = reccnt - 1;
e5229042
SP
2688 if (lastrec) {
2689 if (get_sha1_hex(lastrec, logged_sha1))
2690 die("Log %s is corrupt.", logfile);
2691 if (get_sha1_hex(rec + 41, sha1))
2692 die("Log %s is corrupt.", logfile);
a89fccd2 2693 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2694 warning("Log %s has gap after %s.",
73013afd 2695 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2696 }
e5f38ec3
JH
2697 }
2698 else if (date == at_time) {
e5229042
SP
2699 if (get_sha1_hex(rec + 41, sha1))
2700 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2701 }
2702 else {
e5229042
SP
2703 if (get_sha1_hex(rec + 41, logged_sha1))
2704 die("Log %s is corrupt.", logfile);
a89fccd2 2705 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2706 warning("Log %s unexpectedly ended on %s.",
73013afd 2707 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2708 }
2709 }
dc49cd76 2710 munmap(log_mapped, mapsz);
d556fae2
SP
2711 return 0;
2712 }
e5229042 2713 lastrec = rec;
ab2a1a32
JH
2714 if (cnt > 0)
2715 cnt--;
d556fae2
SP
2716 }
2717
e5229042
SP
2718 rec = logdata;
2719 while (rec < logend && *rec != '>' && *rec != '\n')
2720 rec++;
2721 if (rec == logend || *rec == '\n')
d556fae2 2722 die("Log %s is corrupt.", logfile);
e5229042 2723 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2724 tz = strtoul(tz_c, NULL, 10);
2725 if (get_sha1_hex(logdata, sha1))
2726 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2727 if (is_null_sha1(sha1)) {
2728 if (get_sha1_hex(logdata + 41, sha1))
2729 die("Log %s is corrupt.", logfile);
2730 }
16d7cc90
JH
2731 if (msg)
2732 *msg = ref_msg(logdata, logend);
dc49cd76 2733 munmap(log_mapped, mapsz);
16d7cc90
JH
2734
2735 if (cutoff_time)
2736 *cutoff_time = date;
2737 if (cutoff_tz)
2738 *cutoff_tz = tz;
2739 if (cutoff_cnt)
2740 *cutoff_cnt = reccnt;
2741 return 1;
d556fae2 2742}
2ff81662 2743
9a7a183b
JH
2744static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)
2745{
2746 unsigned char osha1[20], nsha1[20];
2747 char *email_end, *message;
2748 unsigned long timestamp;
2749 int tz;
2750
2751 /* old SP new SP name <email> SP time TAB msg LF */
2752 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||
2753 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||
2754 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||
2755 !(email_end = strchr(sb->buf + 82, '>')) ||
2756 email_end[1] != ' ' ||
2757 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2758 !message || message[0] != ' ' ||
2759 (message[1] != '+' && message[1] != '-') ||
2760 !isdigit(message[2]) || !isdigit(message[3]) ||
2761 !isdigit(message[4]) || !isdigit(message[5]))
2762 return 0; /* corrupt? */
2763 email_end[1] = '\0';
2764 tz = strtol(message + 1, NULL, 10);
2765 if (message[6] != '\t')
2766 message += 6;
2767 else
2768 message += 7;
2769 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);
2770}
2771
98f85ff4
JH
2772static char *find_beginning_of_line(char *bob, char *scan)
2773{
2774 while (bob < scan && *(--scan) != '\n')
2775 ; /* keep scanning backwards */
2776 /*
2777 * Return either beginning of the buffer, or LF at the end of
2778 * the previous line.
2779 */
2780 return scan;
2781}
2782
2783int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)
2ff81662 2784{
8ca78803 2785 struct strbuf sb = STRBUF_INIT;
98f85ff4
JH
2786 FILE *logfp;
2787 long pos;
2788 int ret = 0, at_tail = 1;
2ff81662 2789
7ae07c1b 2790 logfp = fopen(git_path("logs/%s", refname), "r");
2ff81662 2791 if (!logfp)
883d60fa 2792 return -1;
101d15e0 2793
98f85ff4
JH
2794 /* Jump to the end */
2795 if (fseek(logfp, 0, SEEK_END) < 0)
2796 return error("cannot seek back reflog for %s: %s",
2797 refname, strerror(errno));
2798 pos = ftell(logfp);
2799 while (!ret && 0 < pos) {
2800 int cnt;
2801 size_t nread;
2802 char buf[BUFSIZ];
2803 char *endp, *scanp;
2804
2805 /* Fill next block from the end */
2806 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;
2807 if (fseek(logfp, pos - cnt, SEEK_SET))
2808 return error("cannot seek back reflog for %s: %s",
2809 refname, strerror(errno));
2810 nread = fread(buf, cnt, 1, logfp);
e4ca819a 2811 if (nread != 1)
98f85ff4
JH
2812 return error("cannot read %d bytes from reflog for %s: %s",
2813 cnt, refname, strerror(errno));
2814 pos -= cnt;
2815
2816 scanp = endp = buf + cnt;
2817 if (at_tail && scanp[-1] == '\n')
2818 /* Looking at the final LF at the end of the file */
2819 scanp--;
2820 at_tail = 0;
2821
2822 while (buf < scanp) {
2823 /*
2824 * terminating LF of the previous line, or the beginning
2825 * of the buffer.
2826 */
2827 char *bp;
2828
2829 bp = find_beginning_of_line(buf, scanp);
2830
2831 if (*bp != '\n') {
2832 strbuf_splice(&sb, 0, 0, buf, endp - buf);
2833 if (pos)
2834 break; /* need to fill another block */
2835 scanp = buf - 1; /* leave loop */
2836 } else {
2837 /*
2838 * (bp + 1) thru endp is the beginning of the
2839 * current line we have in sb
2840 */
2841 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
2842 scanp = bp;
2843 endp = bp + 1;
2844 }
2845 ret = show_one_reflog_ent(&sb, fn, cb_data);
2846 strbuf_reset(&sb);
2847 if (ret)
2848 break;
9d33f7c2 2849 }
101d15e0 2850
2ff81662 2851 }
98f85ff4 2852 if (!ret && sb.len)
9a7a183b 2853 ret = show_one_reflog_ent(&sb, fn, cb_data);
98f85ff4 2854
2ff81662 2855 fclose(logfp);
8ca78803 2856 strbuf_release(&sb);
2266bf27 2857 return ret;
2ff81662 2858}
e29cb53a 2859
dfefa935 2860int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2861{
98f85ff4
JH
2862 FILE *logfp;
2863 struct strbuf sb = STRBUF_INIT;
2864 int ret = 0;
2865
2866 logfp = fopen(git_path("logs/%s", refname), "r");
2867 if (!logfp)
2868 return -1;
101d15e0 2869
98f85ff4
JH
2870 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))
2871 ret = show_one_reflog_ent(&sb, fn, cb_data);
2872 fclose(logfp);
2873 strbuf_release(&sb);
2874 return ret;
2875}
989c0e5d
MH
2876/*
2877 * Call fn for each reflog in the namespace indicated by name. name
2878 * must be empty or end with '/'. Name will be used as a scratch
2879 * space, but its contents will be restored before return.
2880 */
2881static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 2882{
989c0e5d 2883 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 2884 int retval = 0;
93c603fc 2885 struct dirent *de;
989c0e5d 2886 int oldlen = name->len;
eb8381c8 2887
93c603fc 2888 if (!d)
989c0e5d 2889 return name->len ? errno : 0;
eb8381c8 2890
93c603fc
MH
2891 while ((de = readdir(d)) != NULL) {
2892 struct stat st;
eb8381c8 2893
93c603fc
MH
2894 if (de->d_name[0] == '.')
2895 continue;
93c603fc
MH
2896 if (has_extension(de->d_name, ".lock"))
2897 continue;
989c0e5d
MH
2898 strbuf_addstr(name, de->d_name);
2899 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2900 ; /* silently ignore */
93c603fc 2901 } else {
eb8381c8 2902 if (S_ISDIR(st.st_mode)) {
989c0e5d
MH
2903 strbuf_addch(name, '/');
2904 retval = do_for_each_reflog(name, fn, cb_data);
eb8381c8
NP
2905 } else {
2906 unsigned char sha1[20];
989c0e5d
MH
2907 if (read_ref_full(name->buf, sha1, 0, NULL))
2908 retval = error("bad ref for %s", name->buf);
eb8381c8 2909 else
989c0e5d 2910 retval = fn(name->buf, sha1, 0, cb_data);
eb8381c8
NP
2911 }
2912 if (retval)
2913 break;
2914 }
989c0e5d 2915 strbuf_setlen(name, oldlen);
eb8381c8 2916 }
93c603fc 2917 closedir(d);
eb8381c8
NP
2918 return retval;
2919}
2920
2921int for_each_reflog(each_ref_fn fn, void *cb_data)
2922{
989c0e5d
MH
2923 int retval;
2924 struct strbuf name;
2925 strbuf_init(&name, PATH_MAX);
2926 retval = do_for_each_reflog(&name, fn, cb_data);
2927 strbuf_release(&name);
2928 return retval;
eb8381c8 2929}
3d9f037c
CR
2930
2931int update_ref(const char *action, const char *refname,
2932 const unsigned char *sha1, const unsigned char *oldval,
2933 int flags, enum action_on_err onerr)
2934{
2935 static struct ref_lock *lock;
2936 lock = lock_any_ref_for_update(refname, oldval, flags);
2937 if (!lock) {
2938 const char *str = "Cannot lock the ref '%s'.";
2939 switch (onerr) {
2940 case MSG_ON_ERR: error(str, refname); break;
2941 case DIE_ON_ERR: die(str, refname); break;
2942 case QUIET_ON_ERR: break;
2943 }
2944 return 1;
2945 }
2946 if (write_ref_sha1(lock, sha1, action) < 0) {
2947 const char *str = "Cannot update the ref '%s'.";
2948 switch (onerr) {
2949 case MSG_ON_ERR: error(str, refname); break;
2950 case DIE_ON_ERR: die(str, refname); break;
2951 case QUIET_ON_ERR: break;
2952 }
2953 return 1;
2954 }
2955 return 0;
2956}
cda69f48 2957
5483f799 2958struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2959{
2960 for ( ; list; list = list->next)
2961 if (!strcmp(list->name, name))
5483f799 2962 return (struct ref *)list;
cda69f48
JK
2963 return NULL;
2964}
7c2b3029
JK
2965
2966/*
2967 * generate a format suitable for scanf from a ref_rev_parse_rules
2968 * rule, that is replace the "%.*s" spec with a "%s" spec
2969 */
2970static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2971{
2972 char *spec;
2973
2974 spec = strstr(rule, "%.*s");
2975 if (!spec || strstr(spec + 4, "%.*s"))
2976 die("invalid rule in ref_rev_parse_rules: %s", rule);
2977
2978 /* copy all until spec */
2979 strncpy(scanf_fmt, rule, spec - rule);
2980 scanf_fmt[spec - rule] = '\0';
2981 /* copy new spec */
2982 strcat(scanf_fmt, "%s");
2983 /* copy remaining rule */
2984 strcat(scanf_fmt, spec + 4);
2985
2986 return;
2987}
2988
dfefa935 2989char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2990{
2991 int i;
2992 static char **scanf_fmts;
2993 static int nr_rules;
2994 char *short_name;
2995
2996 /* pre generate scanf formats from ref_rev_parse_rules[] */
2997 if (!nr_rules) {
2998 size_t total_len = 0;
2999
3000 /* the rule list is NULL terminated, count them first */
3001 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
3002 /* no +1 because strlen("%s") < strlen("%.*s") */
3003 total_len += strlen(ref_rev_parse_rules[nr_rules]);
3004
3005 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
3006
3007 total_len = 0;
3008 for (i = 0; i < nr_rules; i++) {
3009 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
3010 + total_len;
3011 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
3012 total_len += strlen(ref_rev_parse_rules[i]);
3013 }
3014 }
3015
3016 /* bail out if there are no rules */
3017 if (!nr_rules)
dfefa935 3018 return xstrdup(refname);
7c2b3029 3019
dfefa935
MH
3020 /* buffer for scanf result, at most refname must fit */
3021 short_name = xstrdup(refname);
7c2b3029
JK
3022
3023 /* skip first rule, it will always match */
3024 for (i = nr_rules - 1; i > 0 ; --i) {
3025 int j;
6e7b3309 3026 int rules_to_fail = i;
7c2b3029
JK
3027 int short_name_len;
3028
dfefa935 3029 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
3030 continue;
3031
3032 short_name_len = strlen(short_name);
3033
6e7b3309
BW
3034 /*
3035 * in strict mode, all (except the matched one) rules
3036 * must fail to resolve to a valid non-ambiguous ref
3037 */
3038 if (strict)
3039 rules_to_fail = nr_rules;
3040
7c2b3029
JK
3041 /*
3042 * check if the short name resolves to a valid ref,
3043 * but use only rules prior to the matched one
3044 */
6e7b3309 3045 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 3046 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
3047 char refname[PATH_MAX];
3048
6e7b3309
BW
3049 /* skip matched rule */
3050 if (i == j)
3051 continue;
3052
7c2b3029
JK
3053 /*
3054 * the short name is ambiguous, if it resolves
3055 * (with this previous rule) to a valid ref
3056 * read_ref() returns 0 on success
3057 */
3058 mksnpath(refname, sizeof(refname),
3059 rule, short_name_len, short_name);
c6893323 3060 if (ref_exists(refname))
7c2b3029
JK
3061 break;
3062 }
3063
3064 /*
3065 * short name is non-ambiguous if all previous rules
3066 * haven't resolved to a valid ref
3067 */
6e7b3309 3068 if (j == rules_to_fail)
7c2b3029
JK
3069 return short_name;
3070 }
3071
3072 free(short_name);
dfefa935 3073 return xstrdup(refname);
7c2b3029 3074}
daebaa78
JH
3075
3076static struct string_list *hide_refs;
3077
3078int parse_hide_refs_config(const char *var, const char *value, const char *section)
3079{
3080 if (!strcmp("transfer.hiderefs", var) ||
3081 /* NEEDSWORK: use parse_config_key() once both are merged */
3082 (!prefixcmp(var, section) && var[strlen(section)] == '.' &&
3083 !strcmp(var + strlen(section), ".hiderefs"))) {
3084 char *ref;
3085 int len;
3086
3087 if (!value)
3088 return config_error_nonbool(var);
3089 ref = xstrdup(value);
3090 len = strlen(ref);
3091 while (len && ref[len - 1] == '/')
3092 ref[--len] = '\0';
3093 if (!hide_refs) {
3094 hide_refs = xcalloc(1, sizeof(*hide_refs));
3095 hide_refs->strdup_strings = 1;
3096 }
3097 string_list_append(hide_refs, ref);
3098 }
3099 return 0;
3100}
3101
3102int ref_is_hidden(const char *refname)
3103{
3104 struct string_list_item *item;
3105
3106 if (!hide_refs)
3107 return 0;
3108 for_each_string_list_item(item, hide_refs) {
3109 int len;
3110 if (prefixcmp(refname, item->string))
3111 continue;
3112 len = strlen(item->string);
3113 if (!refname[len] || refname[len] == '/')
3114 return 1;
3115 }
3116 return 0;
3117}