get_packed_ref_cache: reload packed-refs file when it changes
[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
2fff7812
MH
809struct packed_ref_cache {
810 struct ref_entry *root;
9f69d297 811
5f5e2a88
MH
812 /*
813 * Count of references to the data structure in this instance,
814 * including the pointer from ref_cache::packed if any. The
815 * data will not be freed as long as the reference count is
816 * nonzero.
817 */
818 unsigned int referrers;
819
9f69d297
MH
820 /*
821 * Iff the packed-refs file associated with this instance is
822 * currently locked for writing, this points at the associated
4f6b83e3
MH
823 * lock (which is owned by somebody else). The referrer count
824 * is also incremented when the file is locked and decremented
825 * when it is unlocked.
9f69d297
MH
826 */
827 struct lock_file *lock;
ca919930
JK
828
829 /* The metadata from when this packed-refs cache was read */
830 struct stat_validity validity;
2fff7812
MH
831};
832
5e290ff7
JH
833/*
834 * Future: need to be in "struct repository"
835 * when doing a full libification.
836 */
79c7ca54
MH
837static struct ref_cache {
838 struct ref_cache *next;
d12229f5 839 struct ref_entry *loose;
2fff7812 840 struct packed_ref_cache *packed;
9da31cb0
MH
841 /*
842 * The submodule name, or "" for the main repo. We allocate
843 * length 1 rather than FLEX_ARRAY so that the main ref_cache
844 * is initialized correctly.
845 */
846 char name[1];
847} ref_cache, *submodule_ref_caches;
0e88c130 848
9f69d297
MH
849/* Lock used for the main packed-refs file: */
850static struct lock_file packlock;
851
5f5e2a88
MH
852/*
853 * Increment the reference count of *packed_refs.
854 */
855static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs)
856{
857 packed_refs->referrers++;
858}
859
860/*
861 * Decrease the reference count of *packed_refs. If it goes to zero,
862 * free *packed_refs and return true; otherwise return false.
863 */
864static int release_packed_ref_cache(struct packed_ref_cache *packed_refs)
865{
866 if (!--packed_refs->referrers) {
867 free_ref_entry(packed_refs->root);
ca919930 868 stat_validity_clear(&packed_refs->validity);
5f5e2a88
MH
869 free(packed_refs);
870 return 1;
871 } else {
872 return 0;
873 }
874}
875
760c4512 876static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 877{
d12229f5 878 if (refs->packed) {
5f5e2a88
MH
879 struct packed_ref_cache *packed_refs = refs->packed;
880
881 if (packed_refs->lock)
9f69d297 882 die("internal error: packed-ref cache cleared while locked");
d12229f5 883 refs->packed = NULL;
5f5e2a88 884 release_packed_ref_cache(packed_refs);
d12229f5 885 }
5e290ff7 886}
e1e22e37 887
760c4512
MH
888static void clear_loose_ref_cache(struct ref_cache *refs)
889{
d12229f5
MH
890 if (refs->loose) {
891 free_ref_entry(refs->loose);
892 refs->loose = NULL;
893 }
760c4512
MH
894}
895
79c7ca54 896static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 897{
ce40979c 898 int len;
79c7ca54 899 struct ref_cache *refs;
ce40979c
MH
900 if (!submodule)
901 submodule = "";
902 len = strlen(submodule) + 1;
79c7ca54 903 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 904 memcpy(refs->name, submodule, len);
e5dbf605
MH
905 return refs;
906}
907
4349a668 908/*
79c7ca54 909 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
910 * the main repository, use submodule==NULL. The returned structure
911 * will be allocated and initialized but not necessarily populated; it
912 * should not be freed.
913 */
79c7ca54 914static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 915{
9da31cb0
MH
916 struct ref_cache *refs;
917
918 if (!submodule || !*submodule)
919 return &ref_cache;
920
921 for (refs = submodule_ref_caches; refs; refs = refs->next)
0e88c130
MH
922 if (!strcmp(submodule, refs->name))
923 return refs;
0e88c130 924
79c7ca54 925 refs = create_ref_cache(submodule);
9da31cb0
MH
926 refs->next = submodule_ref_caches;
927 submodule_ref_caches = refs;
0e88c130 928 return refs;
4349a668
MH
929}
930
8be8bde7 931void invalidate_ref_cache(const char *submodule)
f130b116 932{
c5f29abd
MH
933 struct ref_cache *refs = get_ref_cache(submodule);
934 clear_packed_ref_cache(refs);
935 clear_loose_ref_cache(refs);
5e290ff7 936}
e1e22e37 937
3feb4f0c
MH
938/* The length of a peeled reference line in packed-refs, including EOL: */
939#define PEELED_LINE_LENGTH 42
940
694b7a19
MH
941/*
942 * The packed-refs header line that we write out. Perhaps other
943 * traits will be added later. The trailing space is required.
944 */
945static const char PACKED_REFS_HEADER[] =
946 "# pack-refs with: peeled fully-peeled \n";
947
bc5fd6d3
MH
948/*
949 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
950 * Return a pointer to the refname within the line (null-terminated),
951 * or NULL if there was a problem.
952 */
953static const char *parse_ref_line(char *line, unsigned char *sha1)
954{
955 /*
956 * 42: the answer to everything.
957 *
958 * In this case, it happens to be the answer to
959 * 40 (length of sha1 hex representation)
960 * +1 (space in between hex and name)
961 * +1 (newline at the end of the line)
962 */
963 int len = strlen(line) - 42;
964
965 if (len <= 0)
966 return NULL;
967 if (get_sha1_hex(line, sha1) < 0)
968 return NULL;
969 if (!isspace(line[40]))
970 return NULL;
971 line += 41;
972 if (isspace(*line))
973 return NULL;
974 if (line[len] != '\n')
975 return NULL;
976 line[len] = 0;
977
978 return line;
979}
980
c29c46fa
MH
981/*
982 * Read f, which is a packed-refs file, into dir.
983 *
984 * A comment line of the form "# pack-refs with: " may contain zero or
985 * more traits. We interpret the traits as follows:
986 *
987 * No traits:
988 *
989 * Probably no references are peeled. But if the file contains a
990 * peeled value for a reference, we will use it.
991 *
992 * peeled:
993 *
994 * References under "refs/tags/", if they *can* be peeled, *are*
995 * peeled in this file. References outside of "refs/tags/" are
996 * probably not peeled even if they could have been, but if we find
997 * a peeled value for such a reference we will use it.
998 *
999 * fully-peeled:
1000 *
1001 * All references in the file that can be peeled are peeled.
1002 * Inversely (and this is more important), any references in the
1003 * file for which no peeled value is recorded is not peelable. This
1004 * trait should typically be written alongside "peeled" for
1005 * compatibility with older clients, but we do not require it
1006 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
1007 */
d3177275 1008static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 1009{
e9c4c111 1010 struct ref_entry *last = NULL;
f4204ab9 1011 char refline[PATH_MAX];
c29c46fa 1012 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
f4204ab9
JH
1013
1014 while (fgets(refline, sizeof(refline), f)) {
1015 unsigned char sha1[20];
dfefa935 1016 const char *refname;
f4204ab9
JH
1017 static const char header[] = "# pack-refs with:";
1018
1019 if (!strncmp(refline, header, sizeof(header)-1)) {
1020 const char *traits = refline + sizeof(header) - 1;
c29c46fa
MH
1021 if (strstr(traits, " fully-peeled "))
1022 peeled = PEELED_FULLY;
1023 else if (strstr(traits, " peeled "))
1024 peeled = PEELED_TAGS;
f4204ab9
JH
1025 /* perhaps other traits later as well */
1026 continue;
1027 }
1028
dfefa935
MH
1029 refname = parse_ref_line(refline, sha1);
1030 if (refname) {
c29c46fa
MH
1031 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
1032 if (peeled == PEELED_FULLY ||
1033 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
1034 last->flag |= REF_KNOWS_PEELED;
d3177275 1035 add_ref(dir, last);
f4204ab9
JH
1036 continue;
1037 }
1038 if (last &&
1039 refline[0] == '^' &&
3feb4f0c
MH
1040 strlen(refline) == PEELED_LINE_LENGTH &&
1041 refline[PEELED_LINE_LENGTH - 1] == '\n' &&
c29c46fa 1042 !get_sha1_hex(refline + 1, sha1)) {
593f1bb8 1043 hashcpy(last->u.value.peeled, sha1);
c29c46fa
MH
1044 /*
1045 * Regardless of what the file header said,
1046 * we definitely know the value of *this*
1047 * reference:
1048 */
1049 last->flag |= REF_KNOWS_PEELED;
1050 }
f4204ab9 1051 }
f4204ab9
JH
1052}
1053
2fff7812
MH
1054/*
1055 * Get the packed_ref_cache for the specified ref_cache, creating it
1056 * if necessary.
1057 */
1058static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)
5e290ff7 1059{
ca919930
JK
1060 const char *packed_refs_file;
1061
1062 if (*refs->name)
1063 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
1064 else
1065 packed_refs_file = git_path("packed-refs");
1066
1067 if (refs->packed &&
1068 !stat_validity_check(&refs->packed->validity, packed_refs_file))
1069 clear_packed_ref_cache(refs);
1070
d12229f5 1071 if (!refs->packed) {
4349a668 1072 FILE *f;
0bad611b 1073
2fff7812 1074 refs->packed = xcalloc(1, sizeof(*refs->packed));
5f5e2a88 1075 acquire_packed_ref_cache(refs->packed);
2fff7812 1076 refs->packed->root = create_dir_entry(refs, "", 0, 0);
4349a668 1077 f = fopen(packed_refs_file, "r");
e1e22e37 1078 if (f) {
ca919930 1079 stat_validity_update(&refs->packed->validity, fileno(f));
2fff7812 1080 read_packed_refs(f, get_ref_dir(refs->packed->root));
e1e22e37 1081 fclose(f);
e1e22e37 1082 }
e1e22e37 1083 }
2fff7812
MH
1084 return refs->packed;
1085}
1086
1087static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)
1088{
1089 return get_ref_dir(packed_ref_cache->root);
1090}
1091
1092static struct ref_dir *get_packed_refs(struct ref_cache *refs)
1093{
1094 return get_packed_ref_dir(get_packed_ref_cache(refs));
e1e22e37
LT
1095}
1096
30249ee6
MH
1097void add_packed_ref(const char *refname, const unsigned char *sha1)
1098{
9f69d297
MH
1099 struct packed_ref_cache *packed_ref_cache =
1100 get_packed_ref_cache(&ref_cache);
1101
1102 if (!packed_ref_cache->lock)
1103 die("internal error: packed refs not locked");
1104 add_ref(get_packed_ref_dir(packed_ref_cache),
9da31cb0 1105 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
30249ee6
MH
1106}
1107
abc39098 1108/*
28e6a34e
MH
1109 * Read the loose references from the namespace dirname into dir
1110 * (without recursing). dirname must end with '/'. dir must be the
1111 * directory entry corresponding to dirname.
abc39098 1112 */
423a1afc 1113static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 1114{
423a1afc 1115 struct ref_cache *refs = dir->ref_cache;
d3177275 1116 DIR *d;
0bad611b 1117 const char *path;
d5fdae67 1118 struct dirent *de;
abc39098 1119 int dirnamelen = strlen(dirname);
72b64b44 1120 struct strbuf refname;
0bad611b 1121
3b124823 1122 if (*refs->name)
66a3d20b 1123 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 1124 else
66a3d20b 1125 path = git_path("%s", dirname);
0bad611b 1126
d3177275 1127 d = opendir(path);
d5fdae67
MH
1128 if (!d)
1129 return;
1130
66a3d20b
MH
1131 strbuf_init(&refname, dirnamelen + 257);
1132 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
1133
1134 while ((de = readdir(d)) != NULL) {
1135 unsigned char sha1[20];
1136 struct stat st;
1137 int flag;
d5fdae67
MH
1138 const char *refdir;
1139
1140 if (de->d_name[0] == '.')
1141 continue;
d5fdae67
MH
1142 if (has_extension(de->d_name, ".lock"))
1143 continue;
72b64b44 1144 strbuf_addstr(&refname, de->d_name);
d5fdae67 1145 refdir = *refs->name
72b64b44
MH
1146 ? git_path_submodule(refs->name, "%s", refname.buf)
1147 : git_path("%s", refname.buf);
1148 if (stat(refdir, &st) < 0) {
1149 ; /* silently ignore */
1150 } else if (S_ISDIR(st.st_mode)) {
abc39098 1151 strbuf_addch(&refname, '/');
28e6a34e 1152 add_entry_to_dir(dir,
b9146f51
RS
1153 create_dir_entry(refs, refname.buf,
1154 refname.len, 1));
72b64b44 1155 } else {
3b124823 1156 if (*refs->name) {
f8948e2f 1157 hashclr(sha1);
0bad611b 1158 flag = 0;
72b64b44 1159 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
0bad611b 1160 hashclr(sha1);
98ac34b2 1161 flag |= REF_ISBROKEN;
0bad611b 1162 }
72b64b44 1163 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
1164 hashclr(sha1);
1165 flag |= REF_ISBROKEN;
1166 }
9f2fb4a3
MH
1167 add_entry_to_dir(dir,
1168 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 1169 }
66a3d20b 1170 strbuf_setlen(&refname, dirnamelen);
e1e22e37 1171 }
72b64b44 1172 strbuf_release(&refname);
d5fdae67 1173 closedir(d);
e1e22e37
LT
1174}
1175
d3177275 1176static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 1177{
d12229f5 1178 if (!refs->loose) {
28e6a34e
MH
1179 /*
1180 * Mark the top-level directory complete because we
1181 * are about to read the only subdirectory that can
1182 * hold references:
1183 */
b9146f51 1184 refs->loose = create_dir_entry(refs, "", 0, 0);
28e6a34e
MH
1185 /*
1186 * Create an incomplete entry for "refs/":
1187 */
1188 add_entry_to_dir(get_ref_dir(refs->loose),
b9146f51 1189 create_dir_entry(refs, "refs/", 5, 1));
e1e22e37 1190 }
d7826d54 1191 return get_ref_dir(refs->loose);
e1e22e37
LT
1192}
1193
ca8db142
LT
1194/* We allow "recursive" symbolic refs. Only within reason, though */
1195#define MAXDEPTH 5
0ebde32c
LT
1196#define MAXREFLEN (1024)
1197
e5fa45c1
JH
1198/*
1199 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
1200 * from the loose refs in ref_cache refs. Find <refname> in the
1201 * packed-refs file for the submodule.
e5fa45c1 1202 */
b0626608 1203static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 1204 const char *refname, unsigned char *sha1)
0ebde32c 1205{
2c5c66be 1206 struct ref_entry *ref;
d3177275 1207 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 1208
432ad41e 1209 ref = find_ref(dir, refname);
b0626608
MH
1210 if (ref == NULL)
1211 return -1;
1212
593f1bb8 1213 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 1214 return 0;
0ebde32c
LT
1215}
1216
b0626608 1217static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 1218 const char *refname, unsigned char *sha1,
dfefa935 1219 int recursion)
0ebde32c 1220{
064d51dc 1221 int fd, len;
0ebde32c 1222 char buffer[128], *p;
064d51dc 1223 char *path;
0ebde32c 1224
064d51dc 1225 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 1226 return -1;
064d51dc
MH
1227 path = *refs->name
1228 ? git_path_submodule(refs->name, "%s", refname)
1229 : git_path("%s", refname);
1230 fd = open(path, O_RDONLY);
0ebde32c 1231 if (fd < 0)
b0626608 1232 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
1233
1234 len = read(fd, buffer, sizeof(buffer)-1);
1235 close(fd);
1236 if (len < 0)
1237 return -1;
1238 while (len && isspace(buffer[len-1]))
1239 len--;
1240 buffer[len] = 0;
1241
1242 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 1243 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
1244 return 0;
1245
1246 /* Symref? */
1247 if (strncmp(buffer, "ref:", 4))
1248 return -1;
1249 p = buffer + 4;
1250 while (isspace(*p))
1251 p++;
1252
064d51dc 1253 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
1254}
1255
85be1fe3 1256int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
1257{
1258 int len = strlen(path), retval;
064d51dc 1259 char *submodule;
b0626608 1260 struct ref_cache *refs;
0ebde32c
LT
1261
1262 while (len && path[len-1] == '/')
1263 len--;
1264 if (!len)
1265 return -1;
b0626608
MH
1266 submodule = xstrndup(path, len);
1267 refs = get_ref_cache(submodule);
1268 free(submodule);
1269
064d51dc 1270 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
1271 return retval;
1272}
ca8db142 1273
4886b89f 1274/*
63331581
MH
1275 * Return the ref_entry for the given refname from the packed
1276 * references. If it does not exist, return NULL.
4886b89f 1277 */
63331581 1278static struct ref_entry *get_packed_ref(const char *refname)
c224ca7f 1279{
9da31cb0 1280 return find_ref(get_packed_refs(&ref_cache), refname);
c224ca7f
MH
1281}
1282
8d68493f 1283const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 1284{
0104ca09
HO
1285 int depth = MAXDEPTH;
1286 ssize_t len;
a876ed83 1287 char buffer[256];
dfefa935 1288 static char refname_buffer[256];
ca8db142 1289
8da19775
JH
1290 if (flag)
1291 *flag = 0;
1292
dfefa935 1293 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
1294 return NULL;
1295
a876ed83 1296 for (;;) {
55956350 1297 char path[PATH_MAX];
a876ed83
JH
1298 struct stat st;
1299 char *buf;
1300 int fd;
8a65ff76 1301
a876ed83
JH
1302 if (--depth < 0)
1303 return NULL;
ca8db142 1304
dfefa935 1305 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 1306
a876ed83 1307 if (lstat(path, &st) < 0) {
63331581
MH
1308 struct ref_entry *entry;
1309
c224ca7f
MH
1310 if (errno != ENOENT)
1311 return NULL;
1312 /*
1313 * The loose reference file does not exist;
1314 * check for a packed reference.
1315 */
63331581
MH
1316 entry = get_packed_ref(refname);
1317 if (entry) {
1318 hashcpy(sha1, entry->u.value.sha1);
c224ca7f
MH
1319 if (flag)
1320 *flag |= REF_ISPACKED;
dfefa935 1321 return refname;
434cd0cd 1322 }
c224ca7f
MH
1323 /* The reference is not a packed reference, either. */
1324 if (reading) {
a876ed83 1325 return NULL;
c224ca7f
MH
1326 } else {
1327 hashclr(sha1);
dfefa935 1328 return refname;
c224ca7f 1329 }
a876ed83 1330 }
ca8db142 1331
a876ed83
JH
1332 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1333 if (S_ISLNK(st.st_mode)) {
1334 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
1335 if (len < 0)
1336 return NULL;
b54cb795 1337 buffer[len] = 0;
1f58a038
MH
1338 if (!prefixcmp(buffer, "refs/") &&
1339 !check_refname_format(buffer, 0)) {
dfefa935
MH
1340 strcpy(refname_buffer, buffer);
1341 refname = refname_buffer;
8da19775
JH
1342 if (flag)
1343 *flag |= REF_ISSYMREF;
a876ed83
JH
1344 continue;
1345 }
ca8db142 1346 }
a876ed83 1347
7a21632f
DS
1348 /* Is it a directory? */
1349 if (S_ISDIR(st.st_mode)) {
1350 errno = EISDIR;
1351 return NULL;
1352 }
1353
a876ed83
JH
1354 /*
1355 * Anything else, just open it and try to use it as
1356 * a ref
1357 */
1358 fd = open(path, O_RDONLY);
1359 if (fd < 0)
1360 return NULL;
93d26e4c 1361 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1362 close(fd);
28775050
MH
1363 if (len < 0)
1364 return NULL;
1365 while (len && isspace(buffer[len-1]))
1366 len--;
1367 buffer[len] = '\0';
a876ed83
JH
1368
1369 /*
1370 * Is it a symbolic ref?
1371 */
28775050 1372 if (prefixcmp(buffer, "ref:"))
a876ed83 1373 break;
55956350
JH
1374 if (flag)
1375 *flag |= REF_ISSYMREF;
a876ed83 1376 buf = buffer + 4;
28775050
MH
1377 while (isspace(*buf))
1378 buf++;
313fb010 1379 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1380 if (flag)
1381 *flag |= REF_ISBROKEN;
313fb010
MH
1382 return NULL;
1383 }
dfefa935 1384 refname = strcpy(refname_buffer, buf);
8a65ff76 1385 }
f989fea0
MH
1386 /* Please note that FETCH_HEAD has a second line containing other data. */
1387 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1388 if (flag)
1389 *flag |= REF_ISBROKEN;
a876ed83 1390 return NULL;
629cd3ac 1391 }
dfefa935 1392 return refname;
a876ed83
JH
1393}
1394
96ec7b1e
NTND
1395char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1396{
8cad4744 1397 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1398 return ret ? xstrdup(ret) : NULL;
1399}
1400
d08bae7e
IL
1401/* The argument to filter_refs */
1402struct ref_filter {
1403 const char *pattern;
1404 each_ref_fn *fn;
1405 void *cb_data;
1406};
1407
dfefa935 1408int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1409{
8d68493f 1410 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1411 return 0;
1412 return -1;
8a65ff76
LT
1413}
1414
dfefa935 1415int read_ref(const char *refname, unsigned char *sha1)
c6893323 1416{
dfefa935 1417 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1418}
1419
bc5fd6d3 1420int ref_exists(const char *refname)
ef06b918 1421{
bc5fd6d3
MH
1422 unsigned char sha1[20];
1423 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1424}
1425
85be1fe3 1426static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1427 void *data)
d08bae7e
IL
1428{
1429 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1430 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1431 return 0;
85be1fe3 1432 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1433}
1434
68cf8703
MH
1435enum peel_status {
1436 /* object was peeled successfully: */
1437 PEEL_PEELED = 0,
1438
1439 /*
1440 * object cannot be peeled because the named object (or an
1441 * object referred to by a tag in the peel chain), does not
1442 * exist.
1443 */
1444 PEEL_INVALID = -1,
1445
1446 /* object cannot be peeled because it is not a tag: */
9a489f3c
MH
1447 PEEL_NON_TAG = -2,
1448
1449 /* ref_entry contains no peeled value because it is a symref: */
1450 PEEL_IS_SYMREF = -3,
1451
1452 /*
1453 * ref_entry cannot be peeled because it is broken (i.e., the
1454 * symbolic reference cannot even be resolved to an object
1455 * name):
1456 */
1457 PEEL_BROKEN = -4
68cf8703
MH
1458};
1459
cb2ae1c4
MH
1460/*
1461 * Peel the named object; i.e., if the object is a tag, resolve the
68cf8703
MH
1462 * tag recursively until a non-tag is found. If successful, store the
1463 * result to sha1 and return PEEL_PEELED. If the object is not a tag
1464 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
1465 * and leave sha1 unchanged.
cb2ae1c4 1466 */
68cf8703 1467static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
cb2ae1c4
MH
1468{
1469 struct object *o = lookup_unknown_object(name);
1470
1471 if (o->type == OBJ_NONE) {
1472 int type = sha1_object_info(name, NULL);
1473 if (type < 0)
68cf8703 1474 return PEEL_INVALID;
cb2ae1c4
MH
1475 o->type = type;
1476 }
1477
1478 if (o->type != OBJ_TAG)
68cf8703 1479 return PEEL_NON_TAG;
cb2ae1c4
MH
1480
1481 o = deref_tag_noverify(o);
1482 if (!o)
68cf8703 1483 return PEEL_INVALID;
cb2ae1c4
MH
1484
1485 hashcpy(sha1, o->sha1);
68cf8703 1486 return PEEL_PEELED;
cb2ae1c4
MH
1487}
1488
9a489f3c 1489/*
f85354b5
MH
1490 * Peel the entry (if possible) and return its new peel_status. If
1491 * repeel is true, re-peel the entry even if there is an old peeled
1492 * value that is already stored in it.
694b7a19
MH
1493 *
1494 * It is OK to call this function with a packed reference entry that
1495 * might be stale and might even refer to an object that has since
1496 * been garbage-collected. In such a case, if the entry has
1497 * REF_KNOWS_PEELED then leave the status unchanged and return
1498 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.
9a489f3c 1499 */
f85354b5 1500static enum peel_status peel_entry(struct ref_entry *entry, int repeel)
9a489f3c
MH
1501{
1502 enum peel_status status;
1503
f85354b5
MH
1504 if (entry->flag & REF_KNOWS_PEELED) {
1505 if (repeel) {
1506 entry->flag &= ~REF_KNOWS_PEELED;
1507 hashclr(entry->u.value.peeled);
1508 } else {
1509 return is_null_sha1(entry->u.value.peeled) ?
1510 PEEL_NON_TAG : PEEL_PEELED;
1511 }
1512 }
9a489f3c
MH
1513 if (entry->flag & REF_ISBROKEN)
1514 return PEEL_BROKEN;
1515 if (entry->flag & REF_ISSYMREF)
1516 return PEEL_IS_SYMREF;
1517
1518 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);
1519 if (status == PEEL_PEELED || status == PEEL_NON_TAG)
1520 entry->flag |= REF_KNOWS_PEELED;
1521 return status;
1522}
1523
dfefa935 1524int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1525{
1526 int flag;
1527 unsigned char base[20];
cf0adba7 1528
dfefa935 1529 if (current_ref && (current_ref->name == refname
9a489f3c 1530 || !strcmp(current_ref->name, refname))) {
f85354b5 1531 if (peel_entry(current_ref, 0))
9a489f3c
MH
1532 return -1;
1533 hashcpy(sha1, current_ref->u.value.peeled);
1534 return 0;
0ae91be0
SP
1535 }
1536
dfefa935 1537 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1538 return -1;
1539
9a489f3c
MH
1540 /*
1541 * If the reference is packed, read its ref_entry from the
1542 * cache in the hope that we already know its peeled value.
1543 * We only try this optimization on packed references because
1544 * (a) forcing the filling of the loose reference cache could
1545 * be expensive and (b) loose references anyway usually do not
1546 * have REF_KNOWS_PEELED.
1547 */
1548 if (flag & REF_ISPACKED) {
f361baeb 1549 struct ref_entry *r = get_packed_ref(refname);
9a489f3c 1550 if (r) {
f85354b5 1551 if (peel_entry(r, 0))
9a489f3c 1552 return -1;
593f1bb8 1553 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1554 return 0;
cf0adba7 1555 }
cf0adba7
JH
1556 }
1557
cb2ae1c4 1558 return peel_object(base, sha1);
cf0adba7
JH
1559}
1560
bc5fd6d3
MH
1561struct warn_if_dangling_data {
1562 FILE *fp;
1563 const char *refname;
1564 const char *msg_fmt;
1565};
1566
1567static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1568 int flags, void *cb_data)
1569{
1570 struct warn_if_dangling_data *d = cb_data;
1571 const char *resolves_to;
1572 unsigned char junk[20];
1573
1574 if (!(flags & REF_ISSYMREF))
1575 return 0;
1576
1577 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1578 if (!resolves_to || strcmp(resolves_to, d->refname))
1579 return 0;
1580
1581 fprintf(d->fp, d->msg_fmt, refname);
1be65eda 1582 fputc('\n', d->fp);
bc5fd6d3
MH
1583 return 0;
1584}
1585
1586void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1587{
1588 struct warn_if_dangling_data data;
1589
1590 data.fp = fp;
1591 data.refname = refname;
1592 data.msg_fmt = msg_fmt;
1593 for_each_rawref(warn_if_dangling_symref, &data);
1594}
1595
fcce1703 1596/*
65cf102b 1597 * Call fn for each reference in the specified ref_cache, omitting
624cac35
MH
1598 * references not in the containing_dir of base. fn is called for all
1599 * references, including broken ones. If fn ever returns a non-zero
fcce1703
MH
1600 * value, stop the iteration and return that value; otherwise, return
1601 * 0.
1602 */
65cf102b 1603static int do_for_each_entry(struct ref_cache *refs, const char *base,
624cac35 1604 each_ref_entry_fn fn, void *cb_data)
8a65ff76 1605{
8baf2bb9
MH
1606 struct packed_ref_cache *packed_ref_cache = get_packed_ref_cache(refs);
1607 struct ref_dir *packed_dir = get_packed_ref_dir(packed_ref_cache);
933ac036
MH
1608 struct ref_dir *loose_dir = get_loose_refs(refs);
1609 int retval = 0;
1610
8baf2bb9 1611 acquire_packed_ref_cache(packed_ref_cache);
933ac036
MH
1612 if (base && *base) {
1613 packed_dir = find_containing_dir(packed_dir, base, 0);
1614 loose_dir = find_containing_dir(loose_dir, base, 0);
1615 }
1616
1617 if (packed_dir && loose_dir) {
1618 sort_ref_dir(packed_dir);
1619 sort_ref_dir(loose_dir);
624cac35
MH
1620 retval = do_for_each_entry_in_dirs(
1621 packed_dir, loose_dir, fn, cb_data);
933ac036
MH
1622 } else if (packed_dir) {
1623 sort_ref_dir(packed_dir);
624cac35
MH
1624 retval = do_for_each_entry_in_dir(
1625 packed_dir, 0, fn, cb_data);
933ac036
MH
1626 } else if (loose_dir) {
1627 sort_ref_dir(loose_dir);
624cac35
MH
1628 retval = do_for_each_entry_in_dir(
1629 loose_dir, 0, fn, cb_data);
933ac036
MH
1630 }
1631
8baf2bb9 1632 release_packed_ref_cache(packed_ref_cache);
933ac036 1633 return retval;
8a65ff76
LT
1634}
1635
624cac35 1636/*
65cf102b 1637 * Call fn for each reference in the specified ref_cache for which the
624cac35
MH
1638 * refname begins with base. If trim is non-zero, then trim that many
1639 * characters off the beginning of each refname before passing the
1640 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include
1641 * broken references in the iteration. If fn ever returns a non-zero
1642 * value, stop the iteration and return that value; otherwise, return
1643 * 0.
1644 */
65cf102b
MH
1645static int do_for_each_ref(struct ref_cache *refs, const char *base,
1646 each_ref_fn fn, int trim, int flags, void *cb_data)
624cac35
MH
1647{
1648 struct ref_entry_cb data;
1649 data.base = base;
1650 data.trim = trim;
1651 data.flags = flags;
1652 data.fn = fn;
1653 data.cb_data = cb_data;
1654
65cf102b 1655 return do_for_each_entry(refs, base, do_one_ref, &data);
624cac35
MH
1656}
1657
0bad611b 1658static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1659{
1660 unsigned char sha1[20];
8da19775
JH
1661 int flag;
1662
0bad611b
HV
1663 if (submodule) {
1664 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1665 return fn("HEAD", sha1, 0, cb_data);
1666
1667 return 0;
1668 }
1669
c6893323 1670 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1671 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1672
2f34ba32 1673 return 0;
723c31fe
LT
1674}
1675
0bad611b
HV
1676int head_ref(each_ref_fn fn, void *cb_data)
1677{
1678 return do_head_ref(NULL, fn, cb_data);
1679}
1680
9ef6aeb0
HV
1681int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1682{
1683 return do_head_ref(submodule, fn, cb_data);
1684}
1685
cb5d709f 1686int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1687{
9da31cb0 1688 return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);
a62be77f
SE
1689}
1690
9ef6aeb0
HV
1691int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1692{
65cf102b 1693 return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data);
a62be77f
SE
1694}
1695
2a8177b6
CC
1696int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1697{
9da31cb0 1698 return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1699}
1700
9ef6aeb0
HV
1701int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1702 each_ref_fn fn, void *cb_data)
1703{
65cf102b 1704 return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1705}
1706
cb5d709f 1707int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1708{
2a8177b6 1709 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1710}
1711
9ef6aeb0
HV
1712int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1713{
1714 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1715}
1716
cb5d709f 1717int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1718{
2a8177b6 1719 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1720}
1721
9ef6aeb0
HV
1722int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1723{
1724 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1725}
1726
cb5d709f 1727int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1728{
2a8177b6 1729 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1730}
1731
9ef6aeb0
HV
1732int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1733{
1734 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1735}
1736
29268700
CC
1737int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1738{
9da31cb0 1739 return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1740}
1741
a1bea2c1
JT
1742int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1743{
1744 struct strbuf buf = STRBUF_INIT;
1745 int ret = 0;
1746 unsigned char sha1[20];
1747 int flag;
1748
1749 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1750 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1751 ret = fn(buf.buf, sha1, flag, cb_data);
1752 strbuf_release(&buf);
1753
1754 return ret;
1755}
1756
1757int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1758{
1759 struct strbuf buf = STRBUF_INIT;
1760 int ret;
1761 strbuf_addf(&buf, "%srefs/", get_git_namespace());
9da31cb0 1762 ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);
a1bea2c1
JT
1763 strbuf_release(&buf);
1764 return ret;
1765}
1766
b09fe971
IL
1767int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1768 const char *prefix, void *cb_data)
d08bae7e
IL
1769{
1770 struct strbuf real_pattern = STRBUF_INIT;
1771 struct ref_filter filter;
d08bae7e
IL
1772 int ret;
1773
b09fe971 1774 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1775 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1776 else if (prefix)
1777 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1778 strbuf_addstr(&real_pattern, pattern);
1779
894a9d33 1780 if (!has_glob_specials(pattern)) {
9517e6b8 1781 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1782 if (real_pattern.buf[real_pattern.len - 1] != '/')
1783 strbuf_addch(&real_pattern, '/');
1784 /* No need to check for '*', there is none. */
1785 strbuf_addch(&real_pattern, '*');
1786 }
1787
1788 filter.pattern = real_pattern.buf;
1789 filter.fn = fn;
1790 filter.cb_data = cb_data;
1791 ret = for_each_ref(filter_refs, &filter);
1792
1793 strbuf_release(&real_pattern);
1794 return ret;
1795}
1796
b09fe971
IL
1797int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1798{
1799 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1800}
1801
f8948e2f
JH
1802int for_each_rawref(each_ref_fn fn, void *cb_data)
1803{
9da31cb0 1804 return do_for_each_ref(&ref_cache, "", fn, 0,
f8948e2f 1805 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1806}
1807
4577e483 1808const char *prettify_refname(const char *name)
a9c37a72 1809{
a9c37a72
DB
1810 return name + (
1811 !prefixcmp(name, "refs/heads/") ? 11 :
1812 !prefixcmp(name, "refs/tags/") ? 10 :
1813 !prefixcmp(name, "refs/remotes/") ? 13 :
1814 0);
1815}
1816
79803322
SP
1817const char *ref_rev_parse_rules[] = {
1818 "%.*s",
1819 "refs/%.*s",
1820 "refs/tags/%.*s",
1821 "refs/heads/%.*s",
1822 "refs/remotes/%.*s",
1823 "refs/remotes/%.*s/HEAD",
1824 NULL
1825};
1826
1827int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1828{
1829 const char **p;
1830 const int abbrev_name_len = strlen(abbrev_name);
1831
1832 for (p = rules; *p; p++) {
1833 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1834 return 1;
1835 }
1836 }
1837
1838 return 0;
1839}
1840
e5f38ec3 1841static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1842 const unsigned char *old_sha1, int mustexist)
1843{
c6893323 1844 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1845 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1846 unlock_ref(lock);
1847 return NULL;
1848 }
a89fccd2 1849 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1850 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1851 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1852 unlock_ref(lock);
1853 return NULL;
1854 }
1855 return lock;
1856}
1857
7155b727 1858static int remove_empty_directories(const char *file)
bc7127ef
JH
1859{
1860 /* we want to create a file but there is a directory there;
1861 * if that is an empty directory (or a directory that contains
1862 * only empty directories), remove them.
1863 */
7155b727
JS
1864 struct strbuf path;
1865 int result;
bc7127ef 1866
7155b727
JS
1867 strbuf_init(&path, 20);
1868 strbuf_addstr(&path, file);
1869
a0f4afbe 1870 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1871
1872 strbuf_release(&path);
1873
1874 return result;
bc7127ef
JH
1875}
1876
ff74f7f1
JH
1877/*
1878 * *string and *len will only be substituted, and *string returned (for
1879 * later free()ing) if the string passed in is a magic short-hand form
1880 * to name a branch.
1881 */
1882static char *substitute_branch_name(const char **string, int *len)
1883{
1884 struct strbuf buf = STRBUF_INIT;
1885 int ret = interpret_branch_name(*string, &buf);
1886
1887 if (ret == *len) {
1888 size_t size;
1889 *string = strbuf_detach(&buf, &size);
1890 *len = size;
1891 return (char *)*string;
1892 }
1893
1894 return NULL;
1895}
1896
1897int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1898{
1899 char *last_branch = substitute_branch_name(&str, &len);
1900 const char **p, *r;
1901 int refs_found = 0;
1902
1903 *ref = NULL;
1904 for (p = ref_rev_parse_rules; *p; p++) {
1905 char fullref[PATH_MAX];
1906 unsigned char sha1_from_ref[20];
1907 unsigned char *this_result;
1908 int flag;
1909
1910 this_result = refs_found ? sha1_from_ref : sha1;
1911 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1912 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1913 if (r) {
1914 if (!refs_found++)
1915 *ref = xstrdup(r);
1916 if (!warn_ambiguous_refs)
1917 break;
55956350 1918 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1919 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1920 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1921 warning("ignoring broken ref %s.", fullref);
1922 }
ff74f7f1
JH
1923 }
1924 free(last_branch);
1925 return refs_found;
1926}
1927
1928int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1929{
1930 char *last_branch = substitute_branch_name(&str, &len);
1931 const char **p;
1932 int logs_found = 0;
1933
1934 *log = NULL;
1935 for (p = ref_rev_parse_rules; *p; p++) {
1936 struct stat st;
1937 unsigned char hash[20];
1938 char path[PATH_MAX];
1939 const char *ref, *it;
1940
1941 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1942 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1943 if (!ref)
1944 continue;
1945 if (!stat(git_path("logs/%s", path), &st) &&
1946 S_ISREG(st.st_mode))
1947 it = path;
1948 else if (strcmp(ref, path) &&
1949 !stat(git_path("logs/%s", ref), &st) &&
1950 S_ISREG(st.st_mode))
1951 it = ref;
1952 else
1953 continue;
1954 if (!logs_found++) {
1955 *log = xstrdup(it);
1956 hashcpy(sha1, hash);
1957 }
1958 if (!warn_ambiguous_refs)
1959 break;
1960 }
1961 free(last_branch);
1962 return logs_found;
1963}
1964
dfefa935
MH
1965static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1966 const unsigned char *old_sha1,
1967 int flags, int *type_p)
4bd18c43 1968{
434cd0cd 1969 char *ref_file;
dfefa935 1970 const char *orig_refname = refname;
4bd18c43 1971 struct ref_lock *lock;
5cc3cef9 1972 int last_errno = 0;
acd3b9ec 1973 int type, lflags;
4431fcc4 1974 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1975 int missing = 0;
4bd18c43
SP
1976
1977 lock = xcalloc(1, sizeof(struct ref_lock));
1978 lock->lock_fd = -1;
1979
8d68493f 1980 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1981 if (!refname && errno == EISDIR) {
bc7127ef
JH
1982 /* we are trying to lock foo but we used to
1983 * have foo/bar which now does not exist;
1984 * it is normal for the empty directory 'foo'
1985 * to remain.
1986 */
dfefa935 1987 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1988 if (remove_empty_directories(ref_file)) {
1989 last_errno = errno;
dfefa935 1990 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1991 goto error_return;
1992 }
8d68493f 1993 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1994 }
68db31cc
SV
1995 if (type_p)
1996 *type_p = type;
dfefa935 1997 if (!refname) {
5cc3cef9 1998 last_errno = errno;
818f477c 1999 error("unable to resolve reference %s: %s",
dfefa935 2000 orig_refname, strerror(errno));
5cc3cef9 2001 goto error_return;
4bd18c43 2002 }
5bdd8d4a 2003 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
2004 /* When the ref did not exist and we are creating it,
2005 * make sure there is no existing ref that is packed
2006 * whose name begins with our refname, nor a ref whose
2007 * name is a proper prefix of our refname.
2008 */
5bdd8d4a 2009 if (missing &&
9da31cb0 2010 !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {
f475e08e 2011 last_errno = ENOTDIR;
c976d415 2012 goto error_return;
f475e08e 2013 }
22a3844e 2014
c33d5174 2015 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 2016
acd3b9ec
JH
2017 lflags = LOCK_DIE_ON_ERROR;
2018 if (flags & REF_NODEREF) {
dfefa935 2019 refname = orig_refname;
acd3b9ec
JH
2020 lflags |= LOCK_NODEREF;
2021 }
dfefa935
MH
2022 lock->ref_name = xstrdup(refname);
2023 lock->orig_ref_name = xstrdup(orig_refname);
2024 ref_file = git_path("%s", refname);
5bdd8d4a 2025 if (missing)
68db31cc
SV
2026 lock->force_write = 1;
2027 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
2028 lock->force_write = 1;
4bd18c43 2029
5cc3cef9
JH
2030 if (safe_create_leading_directories(ref_file)) {
2031 last_errno = errno;
2032 error("unable to create directory for %s", ref_file);
2033 goto error_return;
2034 }
4bd18c43 2035
acd3b9ec 2036 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 2037 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
2038
2039 error_return:
2040 unlock_ref(lock);
2041 errno = last_errno;
2042 return NULL;
4bd18c43
SP
2043}
2044
dfefa935 2045struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 2046{
53cce84c 2047 char refpath[PATH_MAX];
dfefa935 2048 if (check_refname_format(refname, 0))
4bd18c43 2049 return NULL;
dfefa935 2050 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 2051 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
2052}
2053
dfefa935
MH
2054struct ref_lock *lock_any_ref_for_update(const char *refname,
2055 const unsigned char *old_sha1, int flags)
4bd18c43 2056{
dfefa935 2057 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 2058 return NULL;
dfefa935 2059 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
2060}
2061
fec3137f
MH
2062/*
2063 * Write an entry to the packed-refs file for the specified refname.
2064 * If peeled is non-NULL, write it as the entry's peeled value.
2065 */
2066static void write_packed_entry(int fd, char *refname, unsigned char *sha1,
2067 unsigned char *peeled)
d66da478 2068{
d66da478
MH
2069 char line[PATH_MAX + 100];
2070 int len;
2071
d66da478
MH
2072 len = snprintf(line, sizeof(line), "%s %s\n",
2073 sha1_to_hex(sha1), refname);
2074 /* this should not happen but just being defensive */
2075 if (len > sizeof(line))
2076 die("too long a refname '%s'", refname);
fec3137f
MH
2077 write_or_die(fd, line, len);
2078
2079 if (peeled) {
2080 if (snprintf(line, sizeof(line), "^%s\n",
2081 sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)
2082 die("internal error");
2083 write_or_die(fd, line, PEELED_LINE_LENGTH);
2084 }
2085}
2086
7b40d396
MH
2087/*
2088 * An each_ref_entry_fn that writes the entry to a packed-refs file.
2089 */
2090static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)
2091{
2092 int *fd = cb_data;
2093 enum peel_status peel_status = peel_entry(entry, 0);
2094
2095 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
2096 error("internal error: %s is not a valid packed reference!",
2097 entry->name);
2098 write_packed_entry(*fd, entry->name, entry->u.value.sha1,
2099 peel_status == PEEL_PEELED ?
2100 entry->u.value.peeled : NULL);
2101 return 0;
2102}
2103
9f69d297
MH
2104int lock_packed_refs(int flags)
2105{
2106 struct packed_ref_cache *packed_ref_cache;
2107
2108 /* Discard the old cache because it might be invalid: */
2109 clear_packed_ref_cache(&ref_cache);
2110 if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)
2111 return -1;
2112 /* Read the current packed-refs while holding the lock: */
2113 packed_ref_cache = get_packed_ref_cache(&ref_cache);
2114 packed_ref_cache->lock = &packlock;
4f6b83e3
MH
2115 /* Increment the reference count to prevent it from being freed: */
2116 acquire_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2117 return 0;
2118}
2119
2120int commit_packed_refs(void)
2121{
2122 struct packed_ref_cache *packed_ref_cache =
2123 get_packed_ref_cache(&ref_cache);
2124 int error = 0;
2125
2126 if (!packed_ref_cache->lock)
2127 die("internal error: packed-refs not locked");
2128 write_or_die(packed_ref_cache->lock->fd,
2129 PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
2130
2131 do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),
2132 0, write_packed_entry_fn,
2133 &packed_ref_cache->lock->fd);
2134 if (commit_lock_file(packed_ref_cache->lock))
2135 error = -1;
2136 packed_ref_cache->lock = NULL;
4f6b83e3 2137 release_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2138 return error;
2139}
2140
2141void rollback_packed_refs(void)
2142{
2143 struct packed_ref_cache *packed_ref_cache =
2144 get_packed_ref_cache(&ref_cache);
2145
2146 if (!packed_ref_cache->lock)
2147 die("internal error: packed-refs not locked");
2148 rollback_lock_file(packed_ref_cache->lock);
2149 packed_ref_cache->lock = NULL;
4f6b83e3 2150 release_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2151 clear_packed_ref_cache(&ref_cache);
2152}
2153
32d462ce
MH
2154struct ref_to_prune {
2155 struct ref_to_prune *next;
2156 unsigned char sha1[20];
2157 char name[FLEX_ARRAY];
2158};
2159
2160struct pack_refs_cb_data {
2161 unsigned int flags;
267f9a8c 2162 struct ref_dir *packed_refs;
32d462ce 2163 struct ref_to_prune *ref_to_prune;
32d462ce
MH
2164};
2165
267f9a8c
MH
2166/*
2167 * An each_ref_entry_fn that is run over loose references only. If
2168 * the loose reference can be packed, add an entry in the packed ref
2169 * cache. If the reference should be pruned, also add it to
2170 * ref_to_prune in the pack_refs_cb_data.
2171 */
2172static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)
32d462ce
MH
2173{
2174 struct pack_refs_cb_data *cb = cb_data;
f85354b5 2175 enum peel_status peel_status;
267f9a8c 2176 struct ref_entry *packed_entry;
b2a8226d 2177 int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");
32d462ce 2178
267f9a8c
MH
2179 /* ALWAYS pack tags */
2180 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)
32d462ce
MH
2181 return 0;
2182
b2a8226d
MH
2183 /* Do not pack symbolic or broken refs: */
2184 if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))
2185 return 0;
2186
267f9a8c 2187 /* Add a packed ref cache entry equivalent to the loose entry. */
f85354b5 2188 peel_status = peel_entry(entry, 1);
0f29920f 2189 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
f85354b5
MH
2190 die("internal error peeling reference %s (%s)",
2191 entry->name, sha1_to_hex(entry->u.value.sha1));
267f9a8c
MH
2192 packed_entry = find_ref(cb->packed_refs, entry->name);
2193 if (packed_entry) {
2194 /* Overwrite existing packed entry with info from loose entry */
2195 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;
2196 hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);
2197 } else {
2198 packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,
2199 REF_ISPACKED | REF_KNOWS_PEELED, 0);
2200 add_ref(cb->packed_refs, packed_entry);
2201 }
2202 hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);
32d462ce 2203
267f9a8c
MH
2204 /* Schedule the loose reference for pruning if requested. */
2205 if ((cb->flags & PACK_REFS_PRUNE)) {
12e77559 2206 int namelen = strlen(entry->name) + 1;
32d462ce 2207 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
12e77559
MH
2208 hashcpy(n->sha1, entry->u.value.sha1);
2209 strcpy(n->name, entry->name);
32d462ce
MH
2210 n->next = cb->ref_to_prune;
2211 cb->ref_to_prune = n;
2212 }
d66da478
MH
2213 return 0;
2214}
2215
32d462ce
MH
2216/*
2217 * Remove empty parents, but spare refs/ and immediate subdirs.
2218 * Note: munges *name.
2219 */
2220static void try_remove_empty_parents(char *name)
2221{
2222 char *p, *q;
2223 int i;
2224 p = name;
2225 for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */
2226 while (*p && *p != '/')
2227 p++;
2228 /* tolerate duplicate slashes; see check_refname_format() */
2229 while (*p == '/')
2230 p++;
2231 }
2232 for (q = p; *q; q++)
2233 ;
2234 while (1) {
2235 while (q > p && *q != '/')
2236 q--;
2237 while (q > p && *(q-1) == '/')
2238 q--;
2239 if (q == p)
2240 break;
2241 *q = '\0';
2242 if (rmdir(git_path("%s", name)))
2243 break;
2244 }
2245}
2246
2247/* make sure nobody touched the ref, and unlink */
2248static void prune_ref(struct ref_to_prune *r)
2249{
2250 struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
2251
2252 if (lock) {
2253 unlink_or_warn(git_path("%s", r->name));
2254 unlock_ref(lock);
2255 try_remove_empty_parents(r->name);
2256 }
2257}
2258
2259static void prune_refs(struct ref_to_prune *r)
2260{
2261 while (r) {
2262 prune_ref(r);
2263 r = r->next;
2264 }
2265}
2266
32d462ce
MH
2267int pack_refs(unsigned int flags)
2268{
32d462ce
MH
2269 struct pack_refs_cb_data cbdata;
2270
2271 memset(&cbdata, 0, sizeof(cbdata));
2272 cbdata.flags = flags;
2273
9f69d297 2274 lock_packed_refs(LOCK_DIE_ON_ERROR);
267f9a8c
MH
2275 cbdata.packed_refs = get_packed_refs(&ref_cache);
2276
2277 do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,
2278 pack_if_possible_fn, &cbdata);
32d462ce 2279
9f69d297 2280 if (commit_packed_refs())
32d462ce 2281 die_errno("unable to overwrite old ref-pack file");
9f69d297 2282
32d462ce
MH
2283 prune_refs(cbdata.ref_to_prune);
2284 return 0;
2285}
2286
7b40d396
MH
2287/*
2288 * If entry is no longer needed in packed-refs, add it to the string
2289 * list pointed to by cb_data. Reasons for deleting entries:
2290 *
2291 * - Entry is broken.
2292 * - Entry is overridden by a loose ref.
2293 * - Entry does not point at a valid object.
2294 *
2295 * In the first and third cases, also emit an error message because these
2296 * are indications of repository corruption.
2297 */
2298static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)
c0277d15 2299{
7b40d396 2300 struct string_list *refs_to_delete = cb_data;
fec3137f 2301
ab292bc4
MH
2302 if (entry->flag & REF_ISBROKEN) {
2303 /* This shouldn't happen to packed refs. */
2304 error("%s is broken!", entry->name);
7b40d396 2305 string_list_append(refs_to_delete, entry->name);
c0277d15 2306 return 0;
ab292bc4
MH
2307 }
2308 if (!has_sha1_file(entry->u.value.sha1)) {
2309 unsigned char sha1[20];
2310 int flags;
2311
2312 if (read_ref_full(entry->name, sha1, 0, &flags))
2313 /* We should at least have found the packed ref. */
2314 die("Internal error");
7b40d396 2315 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {
ab292bc4
MH
2316 /*
2317 * This packed reference is overridden by a
2318 * loose reference, so it is OK that its value
2319 * is no longer valid; for example, it might
2320 * refer to an object that has been garbage
2321 * collected. For this purpose we don't even
2322 * care whether the loose reference itself is
2323 * invalid, broken, symbolic, etc. Silently
7b40d396 2324 * remove the packed reference.
ab292bc4 2325 */
7b40d396 2326 string_list_append(refs_to_delete, entry->name);
ab292bc4 2327 return 0;
7b40d396 2328 }
ab292bc4
MH
2329 /*
2330 * There is no overriding loose reference, so the fact
2331 * that this reference doesn't refer to a valid object
2332 * indicates some kind of repository corruption.
2333 * Report the problem, then omit the reference from
2334 * the output.
2335 */
2336 error("%s does not point to a valid object!", entry->name);
7b40d396 2337 string_list_append(refs_to_delete, entry->name);
ab292bc4
MH
2338 return 0;
2339 }
2340
d66da478
MH
2341 return 0;
2342}
2343
c0277d15
JH
2344static int repack_without_ref(const char *refname)
2345{
7618fd80 2346 struct ref_dir *packed;
7b40d396
MH
2347 struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
2348 struct string_list_item *ref_to_delete;
7618fd80
MH
2349
2350 if (!get_packed_ref(refname))
2351 return 0; /* refname does not exist in packed refs */
2352
9f69d297 2353 if (lock_packed_refs(0)) {
1b018fd9 2354 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 2355 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 2356 }
9da31cb0 2357 packed = get_packed_refs(&ref_cache);
7b40d396
MH
2358
2359 /* Remove refname from the cache: */
506a760d
MH
2360 if (remove_entry(packed, refname) == -1) {
2361 /*
2362 * The packed entry disappeared while we were
2363 * acquiring the lock.
2364 */
9f69d297 2365 rollback_packed_refs();
506a760d
MH
2366 return 0;
2367 }
7b40d396
MH
2368
2369 /* Remove any other accumulated cruft: */
2370 do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);
2371 for_each_string_list_item(ref_to_delete, &refs_to_delete) {
2372 if (remove_entry(packed, ref_to_delete->string) == -1)
2373 die("internal error");
2374 }
2375
2376 /* Write what remains: */
9f69d297 2377 return commit_packed_refs();
c0277d15
JH
2378}
2379
eca35a25 2380int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
2381{
2382 struct ref_lock *lock;
eca35a25 2383 int err, i = 0, ret = 0, flag = 0;
c0277d15 2384
547d058f 2385 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
c0277d15
JH
2386 if (!lock)
2387 return 1;
045a476f 2388 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 2389 /* loose */
547d058f
RS
2390 i = strlen(lock->lk->filename) - 5; /* .lock */
2391 lock->lk->filename[i] = 0;
2392 err = unlink_or_warn(lock->lk->filename);
691f1a28 2393 if (err && errno != ENOENT)
c0277d15 2394 ret = 1;
691f1a28 2395
547d058f 2396 lock->lk->filename[i] = '.';
c0277d15
JH
2397 }
2398 /* removing the loose one could have resurrected an earlier
2399 * packed one. Also, if it was not loose we need to repack
2400 * without it.
2401 */
b274a714 2402 ret |= repack_without_ref(lock->ref_name);
c0277d15 2403
691f1a28 2404 unlink_or_warn(git_path("logs/%s", lock->ref_name));
9da31cb0 2405 clear_loose_ref_cache(&ref_cache);
c0277d15
JH
2406 unlock_ref(lock);
2407 return ret;
4bd18c43
SP
2408}
2409
765c2258
PH
2410/*
2411 * People using contrib's git-new-workdir have .git/logs/refs ->
2412 * /some/other/path/.git/logs/refs, and that may live on another device.
2413 *
2414 * IOW, to avoid cross device rename errors, the temporary renamed log must
2415 * live into logs/refs.
2416 */
2417#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
2418
dfefa935 2419int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 2420{
c976d415
LH
2421 unsigned char sha1[20], orig_sha1[20];
2422 int flag = 0, logmoved = 0;
2423 struct ref_lock *lock;
c976d415 2424 struct stat loginfo;
dfefa935 2425 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 2426 const char *symref = NULL;
c976d415 2427
450d4c0f 2428 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 2429 return error("reflog for %s is a symlink", oldrefname);
c976d415 2430
8d68493f 2431 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 2432 if (flag & REF_ISSYMREF)
fa58186c 2433 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 2434 oldrefname);
eca35a25 2435 if (!symref)
dfefa935 2436 return error("refname %s not found", oldrefname);
c976d415 2437
9da31cb0 2438 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))
c976d415
LH
2439 return 1;
2440
9da31cb0 2441 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))
c976d415
LH
2442 return 1;
2443
dfefa935 2444 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 2445 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 2446 oldrefname, strerror(errno));
c976d415 2447
dfefa935
MH
2448 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
2449 error("unable to delete old %s", oldrefname);
c976d415
LH
2450 goto rollback;
2451 }
2452
dfefa935
MH
2453 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
2454 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 2455 if (errno==EISDIR) {
dfefa935
MH
2456 if (remove_empty_directories(git_path("%s", newrefname))) {
2457 error("Directory not empty: %s", newrefname);
c976d415
LH
2458 goto rollback;
2459 }
2460 } else {
dfefa935 2461 error("unable to delete existing %s", newrefname);
c976d415
LH
2462 goto rollback;
2463 }
2464 }
2465
dfefa935
MH
2466 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
2467 error("unable to create directory for %s", newrefname);
c976d415
LH
2468 goto rollback;
2469 }
2470
2471 retry:
dfefa935 2472 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
2473 if (errno==EISDIR || errno==ENOTDIR) {
2474 /*
2475 * rename(a, b) when b is an existing
2476 * directory ought to result in ISDIR, but
2477 * Solaris 5.8 gives ENOTDIR. Sheesh.
2478 */
dfefa935
MH
2479 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
2480 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
2481 goto rollback;
2482 }
2483 goto retry;
2484 } else {
765c2258 2485 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 2486 newrefname, strerror(errno));
c976d415
LH
2487 goto rollback;
2488 }
2489 }
2490 logmoved = log;
2491
dfefa935 2492 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 2493 if (!lock) {
dfefa935 2494 error("unable to lock %s for update", newrefname);
c976d415
LH
2495 goto rollback;
2496 }
c976d415
LH
2497 lock->force_write = 1;
2498 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 2499 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 2500 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
2501 goto rollback;
2502 }
2503
2504 return 0;
2505
2506 rollback:
dfefa935 2507 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 2508 if (!lock) {
dfefa935 2509 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
2510 goto rollbacklog;
2511 }
2512
2513 lock->force_write = 1;
2514 flag = log_all_ref_updates;
2515 log_all_ref_updates = 0;
2516 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 2517 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
2518 log_all_ref_updates = flag;
2519
2520 rollbacklog:
dfefa935 2521 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 2522 error("unable to restore logfile %s from %s: %s",
dfefa935 2523 oldrefname, newrefname, strerror(errno));
c976d415 2524 if (!logmoved && log &&
dfefa935 2525 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 2526 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 2527 oldrefname, strerror(errno));
c976d415
LH
2528
2529 return 1;
2530}
2531
435fc852 2532int close_ref(struct ref_lock *lock)
b531394d
BC
2533{
2534 if (close_lock_file(lock->lk))
2535 return -1;
2536 lock->lock_fd = -1;
2537 return 0;
2538}
2539
435fc852 2540int commit_ref(struct ref_lock *lock)
b531394d
BC
2541{
2542 if (commit_lock_file(lock->lk))
2543 return -1;
2544 lock->lock_fd = -1;
2545 return 0;
2546}
2547
e5f38ec3 2548void unlock_ref(struct ref_lock *lock)
4bd18c43 2549{
4ed7cd3a
BC
2550 /* Do not free lock->lk -- atexit() still looks at them */
2551 if (lock->lk)
2552 rollback_lock_file(lock->lk);
434cd0cd 2553 free(lock->ref_name);
1655707c 2554 free(lock->orig_ref_name);
4bd18c43
SP
2555 free(lock);
2556}
2557
0ec29a47
JH
2558/*
2559 * copy the reflog message msg to buf, which has been allocated sufficiently
2560 * large, while cleaning up the whitespaces. Especially, convert LF to space,
2561 * because reflog file is one line per entry.
2562 */
2563static int copy_msg(char *buf, const char *msg)
2564{
2565 char *cp = buf;
2566 char c;
2567 int wasspace = 1;
2568
2569 *cp++ = '\t';
2570 while ((c = *msg++)) {
2571 if (wasspace && isspace(c))
2572 continue;
2573 wasspace = isspace(c);
2574 if (wasspace)
2575 c = ' ';
2576 *cp++ = c;
2577 }
2578 while (buf < cp && isspace(cp[-1]))
2579 cp--;
2580 *cp++ = '\n';
2581 return cp - buf;
2582}
2583
dfefa935 2584int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 2585{
859c3017 2586 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 2587
dfefa935 2588 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 2589 if (log_all_ref_updates &&
dfefa935
MH
2590 (!prefixcmp(refname, "refs/heads/") ||
2591 !prefixcmp(refname, "refs/remotes/") ||
2592 !prefixcmp(refname, "refs/notes/") ||
2593 !strcmp(refname, "HEAD"))) {
157aaea5 2594 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 2595 return error("unable to create directory for %s",
157aaea5 2596 logfile);
6de08ae6
SP
2597 oflags |= O_CREAT;
2598 }
2599
157aaea5 2600 logfd = open(logfile, oflags, 0666);
6de08ae6 2601 if (logfd < 0) {
1974bf62 2602 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 2603 return 0;
3b463c3f
JH
2604
2605 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 2606 if (remove_empty_directories(logfile)) {
3b463c3f 2607 return error("There are still logs under '%s'",
157aaea5 2608 logfile);
3b463c3f 2609 }
157aaea5 2610 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
2611 }
2612
2613 if (logfd < 0)
2614 return error("Unable to append to %s: %s",
157aaea5 2615 logfile, strerror(errno));
6de08ae6
SP
2616 }
2617
157aaea5 2618 adjust_shared_perm(logfile);
859c3017
EM
2619 close(logfd);
2620 return 0;
2621}
443b92b6 2622
dfefa935 2623static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
2624 const unsigned char *new_sha1, const char *msg)
2625{
2626 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2627 unsigned maxlen, len;
2628 int msglen;
157aaea5 2629 char log_file[PATH_MAX];
859c3017
EM
2630 char *logrec;
2631 const char *committer;
2632
2633 if (log_all_ref_updates < 0)
2634 log_all_ref_updates = !is_bare_repository();
2635
dfefa935 2636 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
2637 if (result)
2638 return result;
2639
2640 logfd = open(log_file, oflags);
2641 if (logfd < 0)
2642 return 0;
0ec29a47 2643 msglen = msg ? strlen(msg) : 0;
774751a8 2644 committer = git_committer_info(0);
8ac65937
JH
2645 maxlen = strlen(committer) + msglen + 100;
2646 logrec = xmalloc(maxlen);
2647 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
2648 sha1_to_hex(old_sha1),
2649 sha1_to_hex(new_sha1),
8ac65937
JH
2650 committer);
2651 if (msglen)
0ec29a47 2652 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 2653 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 2654 free(logrec);
91c8d590 2655 if (close(logfd) != 0 || written != len)
9a13f0b7 2656 return error("Unable to append to %s", log_file);
6de08ae6
SP
2657 return 0;
2658}
2659
c3b0dec5
LT
2660static int is_branch(const char *refname)
2661{
2662 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2663}
2664
4bd18c43
SP
2665int write_ref_sha1(struct ref_lock *lock,
2666 const unsigned char *sha1, const char *logmsg)
2667{
2668 static char term = '\n';
c3b0dec5 2669 struct object *o;
4bd18c43
SP
2670
2671 if (!lock)
95fc7512 2672 return -1;
a89fccd2 2673 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
2674 unlock_ref(lock);
2675 return 0;
95fc7512 2676 }
c3b0dec5
LT
2677 o = parse_object(sha1);
2678 if (!o) {
7be8b3ba 2679 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
2680 lock->ref_name, sha1_to_hex(sha1));
2681 unlock_ref(lock);
2682 return -1;
2683 }
2684 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2685 error("Trying to write non-commit object %s to branch %s",
2686 sha1_to_hex(sha1), lock->ref_name);
2687 unlock_ref(lock);
2688 return -1;
2689 }
93822c22
AW
2690 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2691 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 2692 || close_ref(lock) < 0) {
c33d5174 2693 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
2694 unlock_ref(lock);
2695 return -1;
2696 }
9da31cb0 2697 clear_loose_ref_cache(&ref_cache);
bd104db1
NP
2698 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2699 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2700 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
2701 unlock_ref(lock);
2702 return -1;
2703 }
605fac8b
NP
2704 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2705 /*
2706 * Special hack: If a branch is updated directly and HEAD
2707 * points to it (may happen on the remote side of a push
2708 * for example) then logically the HEAD reflog should be
2709 * updated too.
2710 * A generic solution implies reverse symref information,
2711 * but finding all symrefs pointing to the given branch
2712 * would be rather costly for this rare event (the direct
2713 * update of a branch) to be worth it. So let's cheat and
2714 * check with HEAD only which should cover 99% of all usage
2715 * scenarios (even 100% of the default ones).
2716 */
2717 unsigned char head_sha1[20];
2718 int head_flag;
2719 const char *head_ref;
8cad4744 2720 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2721 if (head_ref && (head_flag & REF_ISSYMREF) &&
2722 !strcmp(head_ref, lock->ref_name))
2723 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2724 }
b531394d 2725 if (commit_ref(lock)) {
434cd0cd 2726 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2727 unlock_ref(lock);
2728 return -1;
2729 }
4bd18c43
SP
2730 unlock_ref(lock);
2731 return 0;
95fc7512 2732}
d556fae2 2733
8b5157e4
NP
2734int create_symref(const char *ref_target, const char *refs_heads_master,
2735 const char *logmsg)
41b625b0
NP
2736{
2737 const char *lockpath;
2738 char ref[1000];
2739 int fd, len, written;
a4f34cbb 2740 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2741 unsigned char old_sha1[20], new_sha1[20];
2742
2743 if (logmsg && read_ref(ref_target, old_sha1))
2744 hashclr(old_sha1);
41b625b0 2745
d48744d1
JH
2746 if (safe_create_leading_directories(git_HEAD) < 0)
2747 return error("unable to create directory for %s", git_HEAD);
2748
41b625b0
NP
2749#ifndef NO_SYMLINK_HEAD
2750 if (prefer_symlink_refs) {
2751 unlink(git_HEAD);
2752 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2753 goto done;
41b625b0
NP
2754 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2755 }
2756#endif
2757
2758 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2759 if (sizeof(ref) <= len) {
2760 error("refname too long: %s", refs_heads_master);
47fc52e2 2761 goto error_free_return;
41b625b0
NP
2762 }
2763 lockpath = mkpath("%s.lock", git_HEAD);
2764 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2765 if (fd < 0) {
2766 error("Unable to open %s for writing", lockpath);
47fc52e2 2767 goto error_free_return;
41b625b0
NP
2768 }
2769 written = write_in_full(fd, ref, len);
91c8d590 2770 if (close(fd) != 0 || written != len) {
41b625b0 2771 error("Unable to write to %s", lockpath);
47fc52e2 2772 goto error_unlink_return;
41b625b0
NP
2773 }
2774 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2775 error("Unable to create %s", git_HEAD);
47fc52e2 2776 goto error_unlink_return;
41b625b0
NP
2777 }
2778 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2779 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2780 error_unlink_return:
691f1a28 2781 unlink_or_warn(lockpath);
47fc52e2
JH
2782 error_free_return:
2783 free(git_HEAD);
2784 return -1;
41b625b0 2785 }
8b5157e4 2786
ee96d11b 2787#ifndef NO_SYMLINK_HEAD
8b5157e4 2788 done:
ee96d11b 2789#endif
8b5157e4
NP
2790 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2791 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2792
47fc52e2 2793 free(git_HEAD);
41b625b0
NP
2794 return 0;
2795}
2796
16d7cc90
JH
2797static char *ref_msg(const char *line, const char *endp)
2798{
2799 const char *ep;
16d7cc90 2800 line += 82;
182af834
PH
2801 ep = memchr(line, '\n', endp - line);
2802 if (!ep)
2803 ep = endp;
2804 return xmemdupz(line, ep - line);
16d7cc90
JH
2805}
2806
dfefa935
MH
2807int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2808 unsigned char *sha1, char **msg,
2809 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2810{
e5229042 2811 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2812 char *tz_c;
e29cb53a 2813 int logfd, tz, reccnt = 0;
d556fae2
SP
2814 struct stat st;
2815 unsigned long date;
e5229042 2816 unsigned char logged_sha1[20];
cb48cb58 2817 void *log_mapped;
dc49cd76 2818 size_t mapsz;
d556fae2 2819
dfefa935 2820 logfile = git_path("logs/%s", refname);
d556fae2
SP
2821 logfd = open(logfile, O_RDONLY, 0);
2822 if (logfd < 0)
d824cbba 2823 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2824 fstat(logfd, &st);
2825 if (!st.st_size)
2826 die("Log %s is empty.", logfile);
dc49cd76
SP
2827 mapsz = xsize_t(st.st_size);
2828 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2829 logdata = log_mapped;
d556fae2
SP
2830 close(logfd);
2831
e5229042 2832 lastrec = NULL;
d556fae2
SP
2833 rec = logend = logdata + st.st_size;
2834 while (logdata < rec) {
e29cb53a 2835 reccnt++;
d556fae2
SP
2836 if (logdata < rec && *(rec-1) == '\n')
2837 rec--;
e5229042
SP
2838 lastgt = NULL;
2839 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2840 rec--;
e5229042
SP
2841 if (*rec == '>')
2842 lastgt = rec;
2843 }
2844 if (!lastgt)
d556fae2 2845 die("Log %s is corrupt.", logfile);
e5229042 2846 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2847 if (date <= at_time || cnt == 0) {
76a44c5c 2848 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2849 if (msg)
2850 *msg = ref_msg(rec, logend);
2851 if (cutoff_time)
2852 *cutoff_time = date;
2853 if (cutoff_tz)
2854 *cutoff_tz = tz;
2855 if (cutoff_cnt)
76a44c5c 2856 *cutoff_cnt = reccnt - 1;
e5229042
SP
2857 if (lastrec) {
2858 if (get_sha1_hex(lastrec, logged_sha1))
2859 die("Log %s is corrupt.", logfile);
2860 if (get_sha1_hex(rec + 41, sha1))
2861 die("Log %s is corrupt.", logfile);
a89fccd2 2862 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2863 warning("Log %s has gap after %s.",
73013afd 2864 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2865 }
e5f38ec3
JH
2866 }
2867 else if (date == at_time) {
e5229042
SP
2868 if (get_sha1_hex(rec + 41, sha1))
2869 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2870 }
2871 else {
e5229042
SP
2872 if (get_sha1_hex(rec + 41, logged_sha1))
2873 die("Log %s is corrupt.", logfile);
a89fccd2 2874 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2875 warning("Log %s unexpectedly ended on %s.",
73013afd 2876 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2877 }
2878 }
dc49cd76 2879 munmap(log_mapped, mapsz);
d556fae2
SP
2880 return 0;
2881 }
e5229042 2882 lastrec = rec;
ab2a1a32
JH
2883 if (cnt > 0)
2884 cnt--;
d556fae2
SP
2885 }
2886
e5229042
SP
2887 rec = logdata;
2888 while (rec < logend && *rec != '>' && *rec != '\n')
2889 rec++;
2890 if (rec == logend || *rec == '\n')
d556fae2 2891 die("Log %s is corrupt.", logfile);
e5229042 2892 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2893 tz = strtoul(tz_c, NULL, 10);
2894 if (get_sha1_hex(logdata, sha1))
2895 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2896 if (is_null_sha1(sha1)) {
2897 if (get_sha1_hex(logdata + 41, sha1))
2898 die("Log %s is corrupt.", logfile);
2899 }
16d7cc90
JH
2900 if (msg)
2901 *msg = ref_msg(logdata, logend);
dc49cd76 2902 munmap(log_mapped, mapsz);
16d7cc90
JH
2903
2904 if (cutoff_time)
2905 *cutoff_time = date;
2906 if (cutoff_tz)
2907 *cutoff_tz = tz;
2908 if (cutoff_cnt)
2909 *cutoff_cnt = reccnt;
2910 return 1;
d556fae2 2911}
2ff81662 2912
9a7a183b
JH
2913static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)
2914{
2915 unsigned char osha1[20], nsha1[20];
2916 char *email_end, *message;
2917 unsigned long timestamp;
2918 int tz;
2919
2920 /* old SP new SP name <email> SP time TAB msg LF */
2921 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||
2922 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||
2923 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||
2924 !(email_end = strchr(sb->buf + 82, '>')) ||
2925 email_end[1] != ' ' ||
2926 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2927 !message || message[0] != ' ' ||
2928 (message[1] != '+' && message[1] != '-') ||
2929 !isdigit(message[2]) || !isdigit(message[3]) ||
2930 !isdigit(message[4]) || !isdigit(message[5]))
2931 return 0; /* corrupt? */
2932 email_end[1] = '\0';
2933 tz = strtol(message + 1, NULL, 10);
2934 if (message[6] != '\t')
2935 message += 6;
2936 else
2937 message += 7;
2938 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);
2939}
2940
98f85ff4
JH
2941static char *find_beginning_of_line(char *bob, char *scan)
2942{
2943 while (bob < scan && *(--scan) != '\n')
2944 ; /* keep scanning backwards */
2945 /*
2946 * Return either beginning of the buffer, or LF at the end of
2947 * the previous line.
2948 */
2949 return scan;
2950}
2951
2952int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)
2ff81662 2953{
8ca78803 2954 struct strbuf sb = STRBUF_INIT;
98f85ff4
JH
2955 FILE *logfp;
2956 long pos;
2957 int ret = 0, at_tail = 1;
2ff81662 2958
7ae07c1b 2959 logfp = fopen(git_path("logs/%s", refname), "r");
2ff81662 2960 if (!logfp)
883d60fa 2961 return -1;
101d15e0 2962
98f85ff4
JH
2963 /* Jump to the end */
2964 if (fseek(logfp, 0, SEEK_END) < 0)
2965 return error("cannot seek back reflog for %s: %s",
2966 refname, strerror(errno));
2967 pos = ftell(logfp);
2968 while (!ret && 0 < pos) {
2969 int cnt;
2970 size_t nread;
2971 char buf[BUFSIZ];
2972 char *endp, *scanp;
2973
2974 /* Fill next block from the end */
2975 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;
2976 if (fseek(logfp, pos - cnt, SEEK_SET))
2977 return error("cannot seek back reflog for %s: %s",
2978 refname, strerror(errno));
2979 nread = fread(buf, cnt, 1, logfp);
e4ca819a 2980 if (nread != 1)
98f85ff4
JH
2981 return error("cannot read %d bytes from reflog for %s: %s",
2982 cnt, refname, strerror(errno));
2983 pos -= cnt;
2984
2985 scanp = endp = buf + cnt;
2986 if (at_tail && scanp[-1] == '\n')
2987 /* Looking at the final LF at the end of the file */
2988 scanp--;
2989 at_tail = 0;
2990
2991 while (buf < scanp) {
2992 /*
2993 * terminating LF of the previous line, or the beginning
2994 * of the buffer.
2995 */
2996 char *bp;
2997
2998 bp = find_beginning_of_line(buf, scanp);
2999
3000 if (*bp != '\n') {
3001 strbuf_splice(&sb, 0, 0, buf, endp - buf);
3002 if (pos)
3003 break; /* need to fill another block */
3004 scanp = buf - 1; /* leave loop */
3005 } else {
3006 /*
3007 * (bp + 1) thru endp is the beginning of the
3008 * current line we have in sb
3009 */
3010 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
3011 scanp = bp;
3012 endp = bp + 1;
3013 }
3014 ret = show_one_reflog_ent(&sb, fn, cb_data);
3015 strbuf_reset(&sb);
3016 if (ret)
3017 break;
9d33f7c2 3018 }
101d15e0 3019
2ff81662 3020 }
98f85ff4 3021 if (!ret && sb.len)
9a7a183b 3022 ret = show_one_reflog_ent(&sb, fn, cb_data);
98f85ff4 3023
2ff81662 3024 fclose(logfp);
8ca78803 3025 strbuf_release(&sb);
2266bf27 3026 return ret;
2ff81662 3027}
e29cb53a 3028
dfefa935 3029int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 3030{
98f85ff4
JH
3031 FILE *logfp;
3032 struct strbuf sb = STRBUF_INIT;
3033 int ret = 0;
3034
3035 logfp = fopen(git_path("logs/%s", refname), "r");
3036 if (!logfp)
3037 return -1;
101d15e0 3038
98f85ff4
JH
3039 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))
3040 ret = show_one_reflog_ent(&sb, fn, cb_data);
3041 fclose(logfp);
3042 strbuf_release(&sb);
3043 return ret;
3044}
989c0e5d
MH
3045/*
3046 * Call fn for each reflog in the namespace indicated by name. name
3047 * must be empty or end with '/'. Name will be used as a scratch
3048 * space, but its contents will be restored before return.
3049 */
3050static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 3051{
989c0e5d 3052 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 3053 int retval = 0;
93c603fc 3054 struct dirent *de;
989c0e5d 3055 int oldlen = name->len;
eb8381c8 3056
93c603fc 3057 if (!d)
989c0e5d 3058 return name->len ? errno : 0;
eb8381c8 3059
93c603fc
MH
3060 while ((de = readdir(d)) != NULL) {
3061 struct stat st;
eb8381c8 3062
93c603fc
MH
3063 if (de->d_name[0] == '.')
3064 continue;
93c603fc
MH
3065 if (has_extension(de->d_name, ".lock"))
3066 continue;
989c0e5d
MH
3067 strbuf_addstr(name, de->d_name);
3068 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
3069 ; /* silently ignore */
93c603fc 3070 } else {
eb8381c8 3071 if (S_ISDIR(st.st_mode)) {
989c0e5d
MH
3072 strbuf_addch(name, '/');
3073 retval = do_for_each_reflog(name, fn, cb_data);
eb8381c8
NP
3074 } else {
3075 unsigned char sha1[20];
989c0e5d
MH
3076 if (read_ref_full(name->buf, sha1, 0, NULL))
3077 retval = error("bad ref for %s", name->buf);
eb8381c8 3078 else
989c0e5d 3079 retval = fn(name->buf, sha1, 0, cb_data);
eb8381c8
NP
3080 }
3081 if (retval)
3082 break;
3083 }
989c0e5d 3084 strbuf_setlen(name, oldlen);
eb8381c8 3085 }
93c603fc 3086 closedir(d);
eb8381c8
NP
3087 return retval;
3088}
3089
3090int for_each_reflog(each_ref_fn fn, void *cb_data)
3091{
989c0e5d
MH
3092 int retval;
3093 struct strbuf name;
3094 strbuf_init(&name, PATH_MAX);
3095 retval = do_for_each_reflog(&name, fn, cb_data);
3096 strbuf_release(&name);
3097 return retval;
eb8381c8 3098}
3d9f037c
CR
3099
3100int update_ref(const char *action, const char *refname,
3101 const unsigned char *sha1, const unsigned char *oldval,
3102 int flags, enum action_on_err onerr)
3103{
3104 static struct ref_lock *lock;
3105 lock = lock_any_ref_for_update(refname, oldval, flags);
3106 if (!lock) {
3107 const char *str = "Cannot lock the ref '%s'.";
3108 switch (onerr) {
3109 case MSG_ON_ERR: error(str, refname); break;
3110 case DIE_ON_ERR: die(str, refname); break;
3111 case QUIET_ON_ERR: break;
3112 }
3113 return 1;
3114 }
3115 if (write_ref_sha1(lock, sha1, action) < 0) {
3116 const char *str = "Cannot update the ref '%s'.";
3117 switch (onerr) {
3118 case MSG_ON_ERR: error(str, refname); break;
3119 case DIE_ON_ERR: die(str, refname); break;
3120 case QUIET_ON_ERR: break;
3121 }
3122 return 1;
3123 }
3124 return 0;
3125}
cda69f48 3126
5483f799 3127struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
3128{
3129 for ( ; list; list = list->next)
3130 if (!strcmp(list->name, name))
5483f799 3131 return (struct ref *)list;
cda69f48
JK
3132 return NULL;
3133}
7c2b3029
JK
3134
3135/*
3136 * generate a format suitable for scanf from a ref_rev_parse_rules
3137 * rule, that is replace the "%.*s" spec with a "%s" spec
3138 */
3139static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
3140{
3141 char *spec;
3142
3143 spec = strstr(rule, "%.*s");
3144 if (!spec || strstr(spec + 4, "%.*s"))
3145 die("invalid rule in ref_rev_parse_rules: %s", rule);
3146
3147 /* copy all until spec */
3148 strncpy(scanf_fmt, rule, spec - rule);
3149 scanf_fmt[spec - rule] = '\0';
3150 /* copy new spec */
3151 strcat(scanf_fmt, "%s");
3152 /* copy remaining rule */
3153 strcat(scanf_fmt, spec + 4);
3154
3155 return;
3156}
3157
dfefa935 3158char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
3159{
3160 int i;
3161 static char **scanf_fmts;
3162 static int nr_rules;
3163 char *short_name;
3164
3165 /* pre generate scanf formats from ref_rev_parse_rules[] */
3166 if (!nr_rules) {
3167 size_t total_len = 0;
3168
3169 /* the rule list is NULL terminated, count them first */
3170 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
3171 /* no +1 because strlen("%s") < strlen("%.*s") */
3172 total_len += strlen(ref_rev_parse_rules[nr_rules]);
3173
3174 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
3175
3176 total_len = 0;
3177 for (i = 0; i < nr_rules; i++) {
3178 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
3179 + total_len;
3180 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
3181 total_len += strlen(ref_rev_parse_rules[i]);
3182 }
3183 }
3184
3185 /* bail out if there are no rules */
3186 if (!nr_rules)
dfefa935 3187 return xstrdup(refname);
7c2b3029 3188
dfefa935
MH
3189 /* buffer for scanf result, at most refname must fit */
3190 short_name = xstrdup(refname);
7c2b3029
JK
3191
3192 /* skip first rule, it will always match */
3193 for (i = nr_rules - 1; i > 0 ; --i) {
3194 int j;
6e7b3309 3195 int rules_to_fail = i;
7c2b3029
JK
3196 int short_name_len;
3197
dfefa935 3198 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
3199 continue;
3200
3201 short_name_len = strlen(short_name);
3202
6e7b3309
BW
3203 /*
3204 * in strict mode, all (except the matched one) rules
3205 * must fail to resolve to a valid non-ambiguous ref
3206 */
3207 if (strict)
3208 rules_to_fail = nr_rules;
3209
7c2b3029
JK
3210 /*
3211 * check if the short name resolves to a valid ref,
3212 * but use only rules prior to the matched one
3213 */
6e7b3309 3214 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 3215 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
3216 char refname[PATH_MAX];
3217
6e7b3309
BW
3218 /* skip matched rule */
3219 if (i == j)
3220 continue;
3221
7c2b3029
JK
3222 /*
3223 * the short name is ambiguous, if it resolves
3224 * (with this previous rule) to a valid ref
3225 * read_ref() returns 0 on success
3226 */
3227 mksnpath(refname, sizeof(refname),
3228 rule, short_name_len, short_name);
c6893323 3229 if (ref_exists(refname))
7c2b3029
JK
3230 break;
3231 }
3232
3233 /*
3234 * short name is non-ambiguous if all previous rules
3235 * haven't resolved to a valid ref
3236 */
6e7b3309 3237 if (j == rules_to_fail)
7c2b3029
JK
3238 return short_name;
3239 }
3240
3241 free(short_name);
dfefa935 3242 return xstrdup(refname);
7c2b3029 3243}
daebaa78
JH
3244
3245static struct string_list *hide_refs;
3246
3247int parse_hide_refs_config(const char *var, const char *value, const char *section)
3248{
3249 if (!strcmp("transfer.hiderefs", var) ||
3250 /* NEEDSWORK: use parse_config_key() once both are merged */
3251 (!prefixcmp(var, section) && var[strlen(section)] == '.' &&
3252 !strcmp(var + strlen(section), ".hiderefs"))) {
3253 char *ref;
3254 int len;
3255
3256 if (!value)
3257 return config_error_nonbool(var);
3258 ref = xstrdup(value);
3259 len = strlen(ref);
3260 while (len && ref[len - 1] == '/')
3261 ref[--len] = '\0';
3262 if (!hide_refs) {
3263 hide_refs = xcalloc(1, sizeof(*hide_refs));
3264 hide_refs->strdup_strings = 1;
3265 }
3266 string_list_append(hide_refs, ref);
3267 }
3268 return 0;
3269}
3270
3271int ref_is_hidden(const char *refname)
3272{
3273 struct string_list_item *item;
3274
3275 if (!hide_refs)
3276 return 0;
3277 for_each_string_list_item(item, hide_refs) {
3278 int len;
3279 if (prefixcmp(refname, item->string))
3280 continue;
3281 len = strlen(item->string);
3282 if (!refname[len] || refname[len] == '/')
3283 return 1;
3284 }
3285 return 0;
3286}