strbuf: introduce starts_with() and ends_with()
[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
9ba89f48
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;
d0cf51e9 637 struct ref_entry *old_current_ref;
429213e4 638 int retval;
d0cf51e9 639
624cac35 640 if (prefixcmp(entry->name, data->base))
bc5fd6d3 641 return 0;
c774aab9 642
624cac35 643 if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
662428f4 644 !ref_resolves_to_object(entry))
bc5fd6d3 645 return 0;
c774aab9 646
d0cf51e9
MH
647 /* Store the old value, in case this is a recursive call: */
648 old_current_ref = current_ref;
bc5fd6d3 649 current_ref = entry;
624cac35
MH
650 retval = data->fn(entry->name + data->trim, entry->u.value.sha1,
651 entry->flag, data->cb_data);
d0cf51e9 652 current_ref = old_current_ref;
429213e4 653 return retval;
bc5fd6d3 654}
c774aab9 655
c36b5bc2 656/*
d3177275 657 * Call fn for each reference in dir that has index in the range
432ad41e
MH
658 * offset <= index < dir->nr. Recurse into subdirectories that are in
659 * that index range, sorting them before iterating. This function
624cac35
MH
660 * does not sort dir itself; it should be sorted beforehand. fn is
661 * called for all references, including broken ones.
c36b5bc2 662 */
624cac35
MH
663static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset,
664 each_ref_entry_fn fn, void *cb_data)
c36b5bc2
MH
665{
666 int i;
d3177275
MH
667 assert(dir->sorted == dir->nr);
668 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
669 struct ref_entry *entry = dir->entries[i];
670 int retval;
671 if (entry->flag & REF_DIR) {
d7826d54
MH
672 struct ref_dir *subdir = get_ref_dir(entry);
673 sort_ref_dir(subdir);
624cac35 674 retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data);
432ad41e 675 } else {
624cac35 676 retval = fn(entry, cb_data);
432ad41e 677 }
c36b5bc2
MH
678 if (retval)
679 return retval;
680 }
681 return 0;
682}
683
b3fd060f 684/*
d3177275 685 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
686 * by refname. Recurse into subdirectories. If a value entry appears
687 * in both dir1 and dir2, then only process the version that is in
688 * dir2. The input dirs must already be sorted, but subdirs will be
624cac35
MH
689 * sorted as needed. fn is called for all references, including
690 * broken ones.
b3fd060f 691 */
624cac35
MH
692static int do_for_each_entry_in_dirs(struct ref_dir *dir1,
693 struct ref_dir *dir2,
694 each_ref_entry_fn fn, void *cb_data)
b3fd060f
MH
695{
696 int retval;
697 int i1 = 0, i2 = 0;
698
d3177275
MH
699 assert(dir1->sorted == dir1->nr);
700 assert(dir2->sorted == dir2->nr);
432ad41e
MH
701 while (1) {
702 struct ref_entry *e1, *e2;
703 int cmp;
704 if (i1 == dir1->nr) {
624cac35 705 return do_for_each_entry_in_dir(dir2, i2, fn, cb_data);
432ad41e
MH
706 }
707 if (i2 == dir2->nr) {
624cac35 708 return do_for_each_entry_in_dir(dir1, i1, fn, cb_data);
432ad41e
MH
709 }
710 e1 = dir1->entries[i1];
711 e2 = dir2->entries[i2];
712 cmp = strcmp(e1->name, e2->name);
713 if (cmp == 0) {
714 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
715 /* Both are directories; descend them in parallel. */
d7826d54
MH
716 struct ref_dir *subdir1 = get_ref_dir(e1);
717 struct ref_dir *subdir2 = get_ref_dir(e2);
718 sort_ref_dir(subdir1);
719 sort_ref_dir(subdir2);
624cac35
MH
720 retval = do_for_each_entry_in_dirs(
721 subdir1, subdir2, fn, cb_data);
432ad41e
MH
722 i1++;
723 i2++;
724 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
725 /* Both are references; ignore the one from dir1. */
624cac35 726 retval = fn(e2, cb_data);
432ad41e
MH
727 i1++;
728 i2++;
729 } else {
730 die("conflict between reference and directory: %s",
731 e1->name);
732 }
b3fd060f 733 } else {
432ad41e
MH
734 struct ref_entry *e;
735 if (cmp < 0) {
736 e = e1;
b3fd060f 737 i1++;
432ad41e
MH
738 } else {
739 e = e2;
740 i2++;
741 }
742 if (e->flag & REF_DIR) {
d7826d54
MH
743 struct ref_dir *subdir = get_ref_dir(e);
744 sort_ref_dir(subdir);
624cac35
MH
745 retval = do_for_each_entry_in_dir(
746 subdir, 0, fn, cb_data);
432ad41e 747 } else {
624cac35 748 retval = fn(e, cb_data);
b3fd060f
MH
749 }
750 }
751 if (retval)
752 return retval;
753 }
b3fd060f
MH
754}
755
98eeb09e
JK
756/*
757 * Load all of the refs from the dir into our in-memory cache. The hard work
758 * of loading loose refs is done by get_ref_dir(), so we just need to recurse
759 * through all of the sub-directories. We do not even need to care about
760 * sorting, as traversal order does not matter to us.
761 */
762static void prime_ref_dir(struct ref_dir *dir)
763{
764 int i;
765 for (i = 0; i < dir->nr; i++) {
766 struct ref_entry *entry = dir->entries[i];
767 if (entry->flag & REF_DIR)
768 prime_ref_dir(get_ref_dir(entry));
769 }
770}
d66da478
MH
771/*
772 * Return true iff refname1 and refname2 conflict with each other.
773 * Two reference names conflict if one of them exactly matches the
774 * leading components of the other; e.g., "foo/bar" conflicts with
775 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
776 * "foo/barbados".
777 */
778static int names_conflict(const char *refname1, const char *refname2)
779{
5a4d4947
MH
780 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
781 ;
782 return (*refname1 == '\0' && *refname2 == '/')
783 || (*refname1 == '/' && *refname2 == '\0');
784}
785
786struct name_conflict_cb {
787 const char *refname;
788 const char *oldrefname;
789 const char *conflicting_refname;
790};
791
624cac35 792static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
5a4d4947
MH
793{
794 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
624cac35 795 if (data->oldrefname && !strcmp(data->oldrefname, entry->name))
5a4d4947 796 return 0;
624cac35
MH
797 if (names_conflict(data->refname, entry->name)) {
798 data->conflicting_refname = entry->name;
5a4d4947 799 return 1;
d66da478 800 }
5a4d4947 801 return 0;
d66da478
MH
802}
803
bc5fd6d3
MH
804/*
805 * Return true iff a reference named refname could be created without
624cac35 806 * conflicting with the name of an existing reference in dir. If
5a4d4947
MH
807 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
808 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
809 * operation).
810 */
811static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 812 struct ref_dir *dir)
bc5fd6d3 813{
5a4d4947
MH
814 struct name_conflict_cb data;
815 data.refname = refname;
816 data.oldrefname = oldrefname;
817 data.conflicting_refname = NULL;
818
d3177275 819 sort_ref_dir(dir);
624cac35 820 if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) {
5a4d4947
MH
821 error("'%s' exists; cannot create '%s'",
822 data.conflicting_refname, refname);
823 return 0;
bc5fd6d3
MH
824 }
825 return 1;
e1e22e37
LT
826}
827
2fff7812
MH
828struct packed_ref_cache {
829 struct ref_entry *root;
9f69d297 830
5f5e2a88
MH
831 /*
832 * Count of references to the data structure in this instance,
833 * including the pointer from ref_cache::packed if any. The
834 * data will not be freed as long as the reference count is
835 * nonzero.
836 */
837 unsigned int referrers;
838
9f69d297
MH
839 /*
840 * Iff the packed-refs file associated with this instance is
841 * currently locked for writing, this points at the associated
4f6b83e3
MH
842 * lock (which is owned by somebody else). The referrer count
843 * is also incremented when the file is locked and decremented
844 * when it is unlocked.
9f69d297
MH
845 */
846 struct lock_file *lock;
ca919930
JK
847
848 /* The metadata from when this packed-refs cache was read */
849 struct stat_validity validity;
2fff7812
MH
850};
851
5e290ff7
JH
852/*
853 * Future: need to be in "struct repository"
854 * when doing a full libification.
855 */
79c7ca54
MH
856static struct ref_cache {
857 struct ref_cache *next;
d12229f5 858 struct ref_entry *loose;
2fff7812 859 struct packed_ref_cache *packed;
9da31cb0
MH
860 /*
861 * The submodule name, or "" for the main repo. We allocate
862 * length 1 rather than FLEX_ARRAY so that the main ref_cache
863 * is initialized correctly.
864 */
865 char name[1];
866} ref_cache, *submodule_ref_caches;
0e88c130 867
9f69d297
MH
868/* Lock used for the main packed-refs file: */
869static struct lock_file packlock;
870
5f5e2a88
MH
871/*
872 * Increment the reference count of *packed_refs.
873 */
874static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs)
875{
876 packed_refs->referrers++;
877}
878
879/*
880 * Decrease the reference count of *packed_refs. If it goes to zero,
881 * free *packed_refs and return true; otherwise return false.
882 */
883static int release_packed_ref_cache(struct packed_ref_cache *packed_refs)
884{
885 if (!--packed_refs->referrers) {
886 free_ref_entry(packed_refs->root);
ca919930 887 stat_validity_clear(&packed_refs->validity);
5f5e2a88
MH
888 free(packed_refs);
889 return 1;
890 } else {
891 return 0;
892 }
893}
894
760c4512 895static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 896{
d12229f5 897 if (refs->packed) {
5f5e2a88
MH
898 struct packed_ref_cache *packed_refs = refs->packed;
899
900 if (packed_refs->lock)
9f69d297 901 die("internal error: packed-ref cache cleared while locked");
d12229f5 902 refs->packed = NULL;
5f5e2a88 903 release_packed_ref_cache(packed_refs);
d12229f5 904 }
5e290ff7 905}
e1e22e37 906
760c4512
MH
907static void clear_loose_ref_cache(struct ref_cache *refs)
908{
d12229f5
MH
909 if (refs->loose) {
910 free_ref_entry(refs->loose);
911 refs->loose = NULL;
912 }
760c4512
MH
913}
914
79c7ca54 915static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 916{
ce40979c 917 int len;
79c7ca54 918 struct ref_cache *refs;
ce40979c
MH
919 if (!submodule)
920 submodule = "";
921 len = strlen(submodule) + 1;
79c7ca54 922 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 923 memcpy(refs->name, submodule, len);
e5dbf605
MH
924 return refs;
925}
926
4349a668 927/*
79c7ca54 928 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
929 * the main repository, use submodule==NULL. The returned structure
930 * will be allocated and initialized but not necessarily populated; it
931 * should not be freed.
932 */
79c7ca54 933static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 934{
9da31cb0
MH
935 struct ref_cache *refs;
936
937 if (!submodule || !*submodule)
938 return &ref_cache;
939
940 for (refs = submodule_ref_caches; refs; refs = refs->next)
0e88c130
MH
941 if (!strcmp(submodule, refs->name))
942 return refs;
0e88c130 943
79c7ca54 944 refs = create_ref_cache(submodule);
9da31cb0
MH
945 refs->next = submodule_ref_caches;
946 submodule_ref_caches = refs;
0e88c130 947 return refs;
4349a668
MH
948}
949
3feb4f0c
MH
950/* The length of a peeled reference line in packed-refs, including EOL: */
951#define PEELED_LINE_LENGTH 42
952
694b7a19
MH
953/*
954 * The packed-refs header line that we write out. Perhaps other
955 * traits will be added later. The trailing space is required.
956 */
957static const char PACKED_REFS_HEADER[] =
958 "# pack-refs with: peeled fully-peeled \n";
959
bc5fd6d3
MH
960/*
961 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
962 * Return a pointer to the refname within the line (null-terminated),
963 * or NULL if there was a problem.
964 */
965static const char *parse_ref_line(char *line, unsigned char *sha1)
966{
967 /*
968 * 42: the answer to everything.
969 *
970 * In this case, it happens to be the answer to
971 * 40 (length of sha1 hex representation)
972 * +1 (space in between hex and name)
973 * +1 (newline at the end of the line)
974 */
975 int len = strlen(line) - 42;
976
977 if (len <= 0)
978 return NULL;
979 if (get_sha1_hex(line, sha1) < 0)
980 return NULL;
981 if (!isspace(line[40]))
982 return NULL;
983 line += 41;
984 if (isspace(*line))
985 return NULL;
986 if (line[len] != '\n')
987 return NULL;
988 line[len] = 0;
989
990 return line;
991}
992
c29c46fa
MH
993/*
994 * Read f, which is a packed-refs file, into dir.
995 *
996 * A comment line of the form "# pack-refs with: " may contain zero or
997 * more traits. We interpret the traits as follows:
998 *
999 * No traits:
1000 *
1001 * Probably no references are peeled. But if the file contains a
1002 * peeled value for a reference, we will use it.
1003 *
1004 * peeled:
1005 *
1006 * References under "refs/tags/", if they *can* be peeled, *are*
1007 * peeled in this file. References outside of "refs/tags/" are
1008 * probably not peeled even if they could have been, but if we find
1009 * a peeled value for such a reference we will use it.
1010 *
1011 * fully-peeled:
1012 *
1013 * All references in the file that can be peeled are peeled.
1014 * Inversely (and this is more important), any references in the
1015 * file for which no peeled value is recorded is not peelable. This
1016 * trait should typically be written alongside "peeled" for
1017 * compatibility with older clients, but we do not require it
1018 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
1019 */
d3177275 1020static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 1021{
e9c4c111 1022 struct ref_entry *last = NULL;
f4204ab9 1023 char refline[PATH_MAX];
c29c46fa 1024 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
f4204ab9
JH
1025
1026 while (fgets(refline, sizeof(refline), f)) {
1027 unsigned char sha1[20];
dfefa935 1028 const char *refname;
f4204ab9
JH
1029 static const char header[] = "# pack-refs with:";
1030
1031 if (!strncmp(refline, header, sizeof(header)-1)) {
1032 const char *traits = refline + sizeof(header) - 1;
c29c46fa
MH
1033 if (strstr(traits, " fully-peeled "))
1034 peeled = PEELED_FULLY;
1035 else if (strstr(traits, " peeled "))
1036 peeled = PEELED_TAGS;
f4204ab9
JH
1037 /* perhaps other traits later as well */
1038 continue;
1039 }
1040
dfefa935
MH
1041 refname = parse_ref_line(refline, sha1);
1042 if (refname) {
c29c46fa
MH
1043 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
1044 if (peeled == PEELED_FULLY ||
1045 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
1046 last->flag |= REF_KNOWS_PEELED;
d3177275 1047 add_ref(dir, last);
f4204ab9
JH
1048 continue;
1049 }
1050 if (last &&
1051 refline[0] == '^' &&
3feb4f0c
MH
1052 strlen(refline) == PEELED_LINE_LENGTH &&
1053 refline[PEELED_LINE_LENGTH - 1] == '\n' &&
c29c46fa 1054 !get_sha1_hex(refline + 1, sha1)) {
593f1bb8 1055 hashcpy(last->u.value.peeled, sha1);
c29c46fa
MH
1056 /*
1057 * Regardless of what the file header said,
1058 * we definitely know the value of *this*
1059 * reference:
1060 */
1061 last->flag |= REF_KNOWS_PEELED;
1062 }
f4204ab9 1063 }
f4204ab9
JH
1064}
1065
2fff7812
MH
1066/*
1067 * Get the packed_ref_cache for the specified ref_cache, creating it
1068 * if necessary.
1069 */
1070static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)
5e290ff7 1071{
ca919930
JK
1072 const char *packed_refs_file;
1073
1074 if (*refs->name)
1075 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
1076 else
1077 packed_refs_file = git_path("packed-refs");
1078
1079 if (refs->packed &&
1080 !stat_validity_check(&refs->packed->validity, packed_refs_file))
1081 clear_packed_ref_cache(refs);
1082
d12229f5 1083 if (!refs->packed) {
4349a668 1084 FILE *f;
0bad611b 1085
2fff7812 1086 refs->packed = xcalloc(1, sizeof(*refs->packed));
5f5e2a88 1087 acquire_packed_ref_cache(refs->packed);
2fff7812 1088 refs->packed->root = create_dir_entry(refs, "", 0, 0);
4349a668 1089 f = fopen(packed_refs_file, "r");
e1e22e37 1090 if (f) {
ca919930 1091 stat_validity_update(&refs->packed->validity, fileno(f));
2fff7812 1092 read_packed_refs(f, get_ref_dir(refs->packed->root));
e1e22e37 1093 fclose(f);
e1e22e37 1094 }
e1e22e37 1095 }
2fff7812
MH
1096 return refs->packed;
1097}
1098
1099static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)
1100{
1101 return get_ref_dir(packed_ref_cache->root);
1102}
1103
1104static struct ref_dir *get_packed_refs(struct ref_cache *refs)
1105{
1106 return get_packed_ref_dir(get_packed_ref_cache(refs));
e1e22e37
LT
1107}
1108
30249ee6
MH
1109void add_packed_ref(const char *refname, const unsigned char *sha1)
1110{
9f69d297
MH
1111 struct packed_ref_cache *packed_ref_cache =
1112 get_packed_ref_cache(&ref_cache);
1113
1114 if (!packed_ref_cache->lock)
1115 die("internal error: packed refs not locked");
1116 add_ref(get_packed_ref_dir(packed_ref_cache),
9da31cb0 1117 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
30249ee6
MH
1118}
1119
abc39098 1120/*
28e6a34e
MH
1121 * Read the loose references from the namespace dirname into dir
1122 * (without recursing). dirname must end with '/'. dir must be the
1123 * directory entry corresponding to dirname.
abc39098 1124 */
423a1afc 1125static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 1126{
423a1afc 1127 struct ref_cache *refs = dir->ref_cache;
d3177275 1128 DIR *d;
0bad611b 1129 const char *path;
d5fdae67 1130 struct dirent *de;
abc39098 1131 int dirnamelen = strlen(dirname);
72b64b44 1132 struct strbuf refname;
0bad611b 1133
3b124823 1134 if (*refs->name)
66a3d20b 1135 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 1136 else
66a3d20b 1137 path = git_path("%s", dirname);
0bad611b 1138
d3177275 1139 d = opendir(path);
d5fdae67
MH
1140 if (!d)
1141 return;
1142
66a3d20b
MH
1143 strbuf_init(&refname, dirnamelen + 257);
1144 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
1145
1146 while ((de = readdir(d)) != NULL) {
1147 unsigned char sha1[20];
1148 struct stat st;
1149 int flag;
d5fdae67
MH
1150 const char *refdir;
1151
1152 if (de->d_name[0] == '.')
1153 continue;
d5fdae67
MH
1154 if (has_extension(de->d_name, ".lock"))
1155 continue;
72b64b44 1156 strbuf_addstr(&refname, de->d_name);
d5fdae67 1157 refdir = *refs->name
72b64b44
MH
1158 ? git_path_submodule(refs->name, "%s", refname.buf)
1159 : git_path("%s", refname.buf);
1160 if (stat(refdir, &st) < 0) {
1161 ; /* silently ignore */
1162 } else if (S_ISDIR(st.st_mode)) {
abc39098 1163 strbuf_addch(&refname, '/');
28e6a34e 1164 add_entry_to_dir(dir,
b9146f51
RS
1165 create_dir_entry(refs, refname.buf,
1166 refname.len, 1));
72b64b44 1167 } else {
3b124823 1168 if (*refs->name) {
f8948e2f 1169 hashclr(sha1);
0bad611b 1170 flag = 0;
72b64b44 1171 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
0bad611b 1172 hashclr(sha1);
98ac34b2 1173 flag |= REF_ISBROKEN;
0bad611b 1174 }
72b64b44 1175 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
1176 hashclr(sha1);
1177 flag |= REF_ISBROKEN;
1178 }
9f2fb4a3
MH
1179 add_entry_to_dir(dir,
1180 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 1181 }
66a3d20b 1182 strbuf_setlen(&refname, dirnamelen);
e1e22e37 1183 }
72b64b44 1184 strbuf_release(&refname);
d5fdae67 1185 closedir(d);
e1e22e37
LT
1186}
1187
d3177275 1188static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 1189{
d12229f5 1190 if (!refs->loose) {
28e6a34e
MH
1191 /*
1192 * Mark the top-level directory complete because we
1193 * are about to read the only subdirectory that can
1194 * hold references:
1195 */
b9146f51 1196 refs->loose = create_dir_entry(refs, "", 0, 0);
28e6a34e
MH
1197 /*
1198 * Create an incomplete entry for "refs/":
1199 */
1200 add_entry_to_dir(get_ref_dir(refs->loose),
b9146f51 1201 create_dir_entry(refs, "refs/", 5, 1));
e1e22e37 1202 }
d7826d54 1203 return get_ref_dir(refs->loose);
e1e22e37
LT
1204}
1205
ca8db142
LT
1206/* We allow "recursive" symbolic refs. Only within reason, though */
1207#define MAXDEPTH 5
0ebde32c
LT
1208#define MAXREFLEN (1024)
1209
e5fa45c1
JH
1210/*
1211 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
1212 * from the loose refs in ref_cache refs. Find <refname> in the
1213 * packed-refs file for the submodule.
e5fa45c1 1214 */
b0626608 1215static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 1216 const char *refname, unsigned char *sha1)
0ebde32c 1217{
2c5c66be 1218 struct ref_entry *ref;
d3177275 1219 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 1220
432ad41e 1221 ref = find_ref(dir, refname);
b0626608
MH
1222 if (ref == NULL)
1223 return -1;
1224
593f1bb8 1225 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 1226 return 0;
0ebde32c
LT
1227}
1228
b0626608 1229static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 1230 const char *refname, unsigned char *sha1,
dfefa935 1231 int recursion)
0ebde32c 1232{
064d51dc 1233 int fd, len;
0ebde32c 1234 char buffer[128], *p;
064d51dc 1235 char *path;
0ebde32c 1236
064d51dc 1237 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 1238 return -1;
064d51dc
MH
1239 path = *refs->name
1240 ? git_path_submodule(refs->name, "%s", refname)
1241 : git_path("%s", refname);
1242 fd = open(path, O_RDONLY);
0ebde32c 1243 if (fd < 0)
b0626608 1244 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
1245
1246 len = read(fd, buffer, sizeof(buffer)-1);
1247 close(fd);
1248 if (len < 0)
1249 return -1;
1250 while (len && isspace(buffer[len-1]))
1251 len--;
1252 buffer[len] = 0;
1253
1254 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 1255 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
1256 return 0;
1257
1258 /* Symref? */
1259 if (strncmp(buffer, "ref:", 4))
1260 return -1;
1261 p = buffer + 4;
1262 while (isspace(*p))
1263 p++;
1264
064d51dc 1265 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
1266}
1267
85be1fe3 1268int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
1269{
1270 int len = strlen(path), retval;
064d51dc 1271 char *submodule;
b0626608 1272 struct ref_cache *refs;
0ebde32c
LT
1273
1274 while (len && path[len-1] == '/')
1275 len--;
1276 if (!len)
1277 return -1;
b0626608
MH
1278 submodule = xstrndup(path, len);
1279 refs = get_ref_cache(submodule);
1280 free(submodule);
1281
064d51dc 1282 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
1283 return retval;
1284}
ca8db142 1285
4886b89f 1286/*
63331581
MH
1287 * Return the ref_entry for the given refname from the packed
1288 * references. If it does not exist, return NULL.
4886b89f 1289 */
63331581 1290static struct ref_entry *get_packed_ref(const char *refname)
c224ca7f 1291{
9da31cb0 1292 return find_ref(get_packed_refs(&ref_cache), refname);
c224ca7f
MH
1293}
1294
47f534bf
MH
1295/*
1296 * A loose ref file doesn't exist; check for a packed ref. The
1297 * options are forwarded from resolve_safe_unsafe().
1298 */
1299static const char *handle_missing_loose_ref(const char *refname,
1300 unsigned char *sha1,
1301 int reading,
1302 int *flag)
1303{
1304 struct ref_entry *entry;
1305
1306 /*
1307 * The loose reference file does not exist; check for a packed
1308 * reference.
1309 */
1310 entry = get_packed_ref(refname);
1311 if (entry) {
1312 hashcpy(sha1, entry->u.value.sha1);
1313 if (flag)
1314 *flag |= REF_ISPACKED;
1315 return refname;
1316 }
1317 /* The reference is not a packed reference, either. */
1318 if (reading) {
1319 return NULL;
1320 } else {
1321 hashclr(sha1);
1322 return refname;
1323 }
1324}
1325
8d68493f 1326const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 1327{
0104ca09
HO
1328 int depth = MAXDEPTH;
1329 ssize_t len;
a876ed83 1330 char buffer[256];
dfefa935 1331 static char refname_buffer[256];
ca8db142 1332
8da19775
JH
1333 if (flag)
1334 *flag = 0;
1335
dfefa935 1336 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
1337 return NULL;
1338
a876ed83 1339 for (;;) {
55956350 1340 char path[PATH_MAX];
a876ed83
JH
1341 struct stat st;
1342 char *buf;
1343 int fd;
8a65ff76 1344
a876ed83
JH
1345 if (--depth < 0)
1346 return NULL;
ca8db142 1347
dfefa935 1348 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 1349
fcb7c762
MH
1350 /*
1351 * We might have to loop back here to avoid a race
1352 * condition: first we lstat() the file, then we try
1353 * to read it as a link or as a file. But if somebody
1354 * changes the type of the file (file <-> directory
1355 * <-> symlink) between the lstat() and reading, then
1356 * we don't want to report that as an error but rather
1357 * try again starting with the lstat().
1358 */
1359 stat_ref:
a876ed83 1360 if (lstat(path, &st) < 0) {
47f534bf
MH
1361 if (errno == ENOENT)
1362 return handle_missing_loose_ref(refname, sha1,
1363 reading, flag);
1364 else
a876ed83 1365 return NULL;
a876ed83 1366 }
ca8db142 1367
a876ed83
JH
1368 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1369 if (S_ISLNK(st.st_mode)) {
1370 len = readlink(path, buffer, sizeof(buffer)-1);
fcb7c762
MH
1371 if (len < 0) {
1372 if (errno == ENOENT || errno == EINVAL)
1373 /* inconsistent with lstat; retry */
1374 goto stat_ref;
1375 else
1376 return NULL;
1377 }
b54cb795 1378 buffer[len] = 0;
1f58a038
MH
1379 if (!prefixcmp(buffer, "refs/") &&
1380 !check_refname_format(buffer, 0)) {
dfefa935
MH
1381 strcpy(refname_buffer, buffer);
1382 refname = refname_buffer;
8da19775
JH
1383 if (flag)
1384 *flag |= REF_ISSYMREF;
a876ed83
JH
1385 continue;
1386 }
ca8db142 1387 }
a876ed83 1388
7a21632f
DS
1389 /* Is it a directory? */
1390 if (S_ISDIR(st.st_mode)) {
1391 errno = EISDIR;
1392 return NULL;
1393 }
1394
a876ed83
JH
1395 /*
1396 * Anything else, just open it and try to use it as
1397 * a ref
1398 */
1399 fd = open(path, O_RDONLY);
fcb7c762
MH
1400 if (fd < 0) {
1401 if (errno == ENOENT)
1402 /* inconsistent with lstat; retry */
1403 goto stat_ref;
1404 else
1405 return NULL;
1406 }
93d26e4c 1407 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1408 close(fd);
28775050
MH
1409 if (len < 0)
1410 return NULL;
1411 while (len && isspace(buffer[len-1]))
1412 len--;
1413 buffer[len] = '\0';
a876ed83
JH
1414
1415 /*
1416 * Is it a symbolic ref?
1417 */
2884c06a
MH
1418 if (prefixcmp(buffer, "ref:")) {
1419 /*
1420 * Please note that FETCH_HEAD has a second
1421 * line containing other data.
1422 */
1423 if (get_sha1_hex(buffer, sha1) ||
1424 (buffer[40] != '\0' && !isspace(buffer[40]))) {
1425 if (flag)
1426 *flag |= REF_ISBROKEN;
1427 return NULL;
1428 }
1429 return refname;
1430 }
55956350
JH
1431 if (flag)
1432 *flag |= REF_ISSYMREF;
a876ed83 1433 buf = buffer + 4;
28775050
MH
1434 while (isspace(*buf))
1435 buf++;
313fb010 1436 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1437 if (flag)
1438 *flag |= REF_ISBROKEN;
313fb010
MH
1439 return NULL;
1440 }
dfefa935 1441 refname = strcpy(refname_buffer, buf);
8a65ff76 1442 }
a876ed83
JH
1443}
1444
96ec7b1e
NTND
1445char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1446{
8cad4744 1447 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1448 return ret ? xstrdup(ret) : NULL;
1449}
1450
d08bae7e
IL
1451/* The argument to filter_refs */
1452struct ref_filter {
1453 const char *pattern;
1454 each_ref_fn *fn;
1455 void *cb_data;
1456};
1457
dfefa935 1458int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1459{
8d68493f 1460 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1461 return 0;
1462 return -1;
8a65ff76
LT
1463}
1464
dfefa935 1465int read_ref(const char *refname, unsigned char *sha1)
c6893323 1466{
dfefa935 1467 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1468}
1469
bc5fd6d3 1470int ref_exists(const char *refname)
ef06b918 1471{
bc5fd6d3
MH
1472 unsigned char sha1[20];
1473 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1474}
1475
85be1fe3 1476static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1477 void *data)
d08bae7e
IL
1478{
1479 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1480 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1481 return 0;
85be1fe3 1482 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1483}
1484
68cf8703
MH
1485enum peel_status {
1486 /* object was peeled successfully: */
1487 PEEL_PEELED = 0,
1488
1489 /*
1490 * object cannot be peeled because the named object (or an
1491 * object referred to by a tag in the peel chain), does not
1492 * exist.
1493 */
1494 PEEL_INVALID = -1,
1495
1496 /* object cannot be peeled because it is not a tag: */
9a489f3c
MH
1497 PEEL_NON_TAG = -2,
1498
1499 /* ref_entry contains no peeled value because it is a symref: */
1500 PEEL_IS_SYMREF = -3,
1501
1502 /*
1503 * ref_entry cannot be peeled because it is broken (i.e., the
1504 * symbolic reference cannot even be resolved to an object
1505 * name):
1506 */
1507 PEEL_BROKEN = -4
68cf8703
MH
1508};
1509
cb2ae1c4
MH
1510/*
1511 * Peel the named object; i.e., if the object is a tag, resolve the
68cf8703
MH
1512 * tag recursively until a non-tag is found. If successful, store the
1513 * result to sha1 and return PEEL_PEELED. If the object is not a tag
1514 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
1515 * and leave sha1 unchanged.
cb2ae1c4 1516 */
68cf8703 1517static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
cb2ae1c4
MH
1518{
1519 struct object *o = lookup_unknown_object(name);
1520
1521 if (o->type == OBJ_NONE) {
1522 int type = sha1_object_info(name, NULL);
1523 if (type < 0)
68cf8703 1524 return PEEL_INVALID;
cb2ae1c4
MH
1525 o->type = type;
1526 }
1527
1528 if (o->type != OBJ_TAG)
68cf8703 1529 return PEEL_NON_TAG;
cb2ae1c4
MH
1530
1531 o = deref_tag_noverify(o);
1532 if (!o)
68cf8703 1533 return PEEL_INVALID;
cb2ae1c4
MH
1534
1535 hashcpy(sha1, o->sha1);
68cf8703 1536 return PEEL_PEELED;
cb2ae1c4
MH
1537}
1538
9a489f3c 1539/*
f85354b5
MH
1540 * Peel the entry (if possible) and return its new peel_status. If
1541 * repeel is true, re-peel the entry even if there is an old peeled
1542 * value that is already stored in it.
694b7a19
MH
1543 *
1544 * It is OK to call this function with a packed reference entry that
1545 * might be stale and might even refer to an object that has since
1546 * been garbage-collected. In such a case, if the entry has
1547 * REF_KNOWS_PEELED then leave the status unchanged and return
1548 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.
9a489f3c 1549 */
f85354b5 1550static enum peel_status peel_entry(struct ref_entry *entry, int repeel)
9a489f3c
MH
1551{
1552 enum peel_status status;
1553
f85354b5
MH
1554 if (entry->flag & REF_KNOWS_PEELED) {
1555 if (repeel) {
1556 entry->flag &= ~REF_KNOWS_PEELED;
1557 hashclr(entry->u.value.peeled);
1558 } else {
1559 return is_null_sha1(entry->u.value.peeled) ?
1560 PEEL_NON_TAG : PEEL_PEELED;
1561 }
1562 }
9a489f3c
MH
1563 if (entry->flag & REF_ISBROKEN)
1564 return PEEL_BROKEN;
1565 if (entry->flag & REF_ISSYMREF)
1566 return PEEL_IS_SYMREF;
1567
1568 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);
1569 if (status == PEEL_PEELED || status == PEEL_NON_TAG)
1570 entry->flag |= REF_KNOWS_PEELED;
1571 return status;
1572}
1573
dfefa935 1574int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1575{
1576 int flag;
1577 unsigned char base[20];
cf0adba7 1578
dfefa935 1579 if (current_ref && (current_ref->name == refname
9a489f3c 1580 || !strcmp(current_ref->name, refname))) {
f85354b5 1581 if (peel_entry(current_ref, 0))
9a489f3c
MH
1582 return -1;
1583 hashcpy(sha1, current_ref->u.value.peeled);
1584 return 0;
0ae91be0
SP
1585 }
1586
dfefa935 1587 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1588 return -1;
1589
9a489f3c
MH
1590 /*
1591 * If the reference is packed, read its ref_entry from the
1592 * cache in the hope that we already know its peeled value.
1593 * We only try this optimization on packed references because
1594 * (a) forcing the filling of the loose reference cache could
1595 * be expensive and (b) loose references anyway usually do not
1596 * have REF_KNOWS_PEELED.
1597 */
1598 if (flag & REF_ISPACKED) {
f361baeb 1599 struct ref_entry *r = get_packed_ref(refname);
9a489f3c 1600 if (r) {
f85354b5 1601 if (peel_entry(r, 0))
9a489f3c 1602 return -1;
593f1bb8 1603 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1604 return 0;
cf0adba7 1605 }
cf0adba7
JH
1606 }
1607
cb2ae1c4 1608 return peel_object(base, sha1);
cf0adba7
JH
1609}
1610
bc5fd6d3
MH
1611struct warn_if_dangling_data {
1612 FILE *fp;
1613 const char *refname;
1614 const char *msg_fmt;
1615};
1616
1617static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1618 int flags, void *cb_data)
1619{
1620 struct warn_if_dangling_data *d = cb_data;
1621 const char *resolves_to;
1622 unsigned char junk[20];
1623
1624 if (!(flags & REF_ISSYMREF))
1625 return 0;
1626
1627 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1628 if (!resolves_to || strcmp(resolves_to, d->refname))
1629 return 0;
1630
1631 fprintf(d->fp, d->msg_fmt, refname);
1be65eda 1632 fputc('\n', d->fp);
bc5fd6d3
MH
1633 return 0;
1634}
1635
1636void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1637{
1638 struct warn_if_dangling_data data;
1639
1640 data.fp = fp;
1641 data.refname = refname;
1642 data.msg_fmt = msg_fmt;
1643 for_each_rawref(warn_if_dangling_symref, &data);
1644}
1645
fcce1703 1646/*
65cf102b 1647 * Call fn for each reference in the specified ref_cache, omitting
624cac35
MH
1648 * references not in the containing_dir of base. fn is called for all
1649 * references, including broken ones. If fn ever returns a non-zero
fcce1703
MH
1650 * value, stop the iteration and return that value; otherwise, return
1651 * 0.
1652 */
65cf102b 1653static int do_for_each_entry(struct ref_cache *refs, const char *base,
624cac35 1654 each_ref_entry_fn fn, void *cb_data)
8a65ff76 1655{
98eeb09e
JK
1656 struct packed_ref_cache *packed_ref_cache;
1657 struct ref_dir *loose_dir;
1658 struct ref_dir *packed_dir;
933ac036
MH
1659 int retval = 0;
1660
98eeb09e
JK
1661 /*
1662 * We must make sure that all loose refs are read before accessing the
1663 * packed-refs file; this avoids a race condition in which loose refs
1664 * are migrated to the packed-refs file by a simultaneous process, but
1665 * our in-memory view is from before the migration. get_packed_ref_cache()
1666 * takes care of making sure our view is up to date with what is on
1667 * disk.
1668 */
1669 loose_dir = get_loose_refs(refs);
933ac036 1670 if (base && *base) {
933ac036
MH
1671 loose_dir = find_containing_dir(loose_dir, base, 0);
1672 }
98eeb09e
JK
1673 if (loose_dir)
1674 prime_ref_dir(loose_dir);
1675
1676 packed_ref_cache = get_packed_ref_cache(refs);
8baf2bb9 1677 acquire_packed_ref_cache(packed_ref_cache);
98eeb09e 1678 packed_dir = get_packed_ref_dir(packed_ref_cache);
933ac036
MH
1679 if (base && *base) {
1680 packed_dir = find_containing_dir(packed_dir, base, 0);
933ac036
MH
1681 }
1682
1683 if (packed_dir && loose_dir) {
1684 sort_ref_dir(packed_dir);
1685 sort_ref_dir(loose_dir);
624cac35
MH
1686 retval = do_for_each_entry_in_dirs(
1687 packed_dir, loose_dir, fn, cb_data);
933ac036
MH
1688 } else if (packed_dir) {
1689 sort_ref_dir(packed_dir);
624cac35
MH
1690 retval = do_for_each_entry_in_dir(
1691 packed_dir, 0, fn, cb_data);
933ac036
MH
1692 } else if (loose_dir) {
1693 sort_ref_dir(loose_dir);
624cac35
MH
1694 retval = do_for_each_entry_in_dir(
1695 loose_dir, 0, fn, cb_data);
933ac036
MH
1696 }
1697
8baf2bb9 1698 release_packed_ref_cache(packed_ref_cache);
933ac036 1699 return retval;
8a65ff76
LT
1700}
1701
624cac35 1702/*
65cf102b 1703 * Call fn for each reference in the specified ref_cache for which the
624cac35
MH
1704 * refname begins with base. If trim is non-zero, then trim that many
1705 * characters off the beginning of each refname before passing the
1706 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include
1707 * broken references in the iteration. If fn ever returns a non-zero
1708 * value, stop the iteration and return that value; otherwise, return
1709 * 0.
1710 */
65cf102b
MH
1711static int do_for_each_ref(struct ref_cache *refs, const char *base,
1712 each_ref_fn fn, int trim, int flags, void *cb_data)
624cac35
MH
1713{
1714 struct ref_entry_cb data;
1715 data.base = base;
1716 data.trim = trim;
1717 data.flags = flags;
1718 data.fn = fn;
1719 data.cb_data = cb_data;
1720
65cf102b 1721 return do_for_each_entry(refs, base, do_one_ref, &data);
624cac35
MH
1722}
1723
0bad611b 1724static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1725{
1726 unsigned char sha1[20];
8da19775
JH
1727 int flag;
1728
0bad611b
HV
1729 if (submodule) {
1730 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1731 return fn("HEAD", sha1, 0, cb_data);
1732
1733 return 0;
1734 }
1735
c6893323 1736 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1737 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1738
2f34ba32 1739 return 0;
723c31fe
LT
1740}
1741
0bad611b
HV
1742int head_ref(each_ref_fn fn, void *cb_data)
1743{
1744 return do_head_ref(NULL, fn, cb_data);
1745}
1746
9ef6aeb0
HV
1747int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1748{
1749 return do_head_ref(submodule, fn, cb_data);
1750}
1751
cb5d709f 1752int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1753{
9da31cb0 1754 return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);
a62be77f
SE
1755}
1756
9ef6aeb0
HV
1757int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1758{
65cf102b 1759 return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data);
a62be77f
SE
1760}
1761
2a8177b6
CC
1762int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1763{
9da31cb0 1764 return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1765}
1766
9ef6aeb0
HV
1767int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1768 each_ref_fn fn, void *cb_data)
1769{
65cf102b 1770 return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1771}
1772
cb5d709f 1773int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1774{
2a8177b6 1775 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1776}
1777
9ef6aeb0
HV
1778int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1779{
1780 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1781}
1782
cb5d709f 1783int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1784{
2a8177b6 1785 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1786}
1787
9ef6aeb0
HV
1788int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1789{
1790 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1791}
1792
cb5d709f 1793int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1794{
2a8177b6 1795 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1796}
1797
9ef6aeb0
HV
1798int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1799{
1800 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1801}
1802
29268700
CC
1803int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1804{
9da31cb0 1805 return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1806}
1807
a1bea2c1
JT
1808int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1809{
1810 struct strbuf buf = STRBUF_INIT;
1811 int ret = 0;
1812 unsigned char sha1[20];
1813 int flag;
1814
1815 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1816 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1817 ret = fn(buf.buf, sha1, flag, cb_data);
1818 strbuf_release(&buf);
1819
1820 return ret;
1821}
1822
1823int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1824{
1825 struct strbuf buf = STRBUF_INIT;
1826 int ret;
1827 strbuf_addf(&buf, "%srefs/", get_git_namespace());
9da31cb0 1828 ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);
a1bea2c1
JT
1829 strbuf_release(&buf);
1830 return ret;
1831}
1832
b09fe971
IL
1833int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1834 const char *prefix, void *cb_data)
d08bae7e
IL
1835{
1836 struct strbuf real_pattern = STRBUF_INIT;
1837 struct ref_filter filter;
d08bae7e
IL
1838 int ret;
1839
b09fe971 1840 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1841 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1842 else if (prefix)
1843 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1844 strbuf_addstr(&real_pattern, pattern);
1845
894a9d33 1846 if (!has_glob_specials(pattern)) {
9517e6b8 1847 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1848 if (real_pattern.buf[real_pattern.len - 1] != '/')
1849 strbuf_addch(&real_pattern, '/');
1850 /* No need to check for '*', there is none. */
1851 strbuf_addch(&real_pattern, '*');
1852 }
1853
1854 filter.pattern = real_pattern.buf;
1855 filter.fn = fn;
1856 filter.cb_data = cb_data;
1857 ret = for_each_ref(filter_refs, &filter);
1858
1859 strbuf_release(&real_pattern);
1860 return ret;
1861}
1862
b09fe971
IL
1863int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1864{
1865 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1866}
1867
f8948e2f
JH
1868int for_each_rawref(each_ref_fn fn, void *cb_data)
1869{
9da31cb0 1870 return do_for_each_ref(&ref_cache, "", fn, 0,
f8948e2f 1871 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1872}
1873
4577e483 1874const char *prettify_refname(const char *name)
a9c37a72 1875{
a9c37a72
DB
1876 return name + (
1877 !prefixcmp(name, "refs/heads/") ? 11 :
1878 !prefixcmp(name, "refs/tags/") ? 10 :
1879 !prefixcmp(name, "refs/remotes/") ? 13 :
1880 0);
1881}
1882
79803322
SP
1883const char *ref_rev_parse_rules[] = {
1884 "%.*s",
1885 "refs/%.*s",
1886 "refs/tags/%.*s",
1887 "refs/heads/%.*s",
1888 "refs/remotes/%.*s",
1889 "refs/remotes/%.*s/HEAD",
1890 NULL
1891};
1892
1893int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1894{
1895 const char **p;
1896 const int abbrev_name_len = strlen(abbrev_name);
1897
1898 for (p = rules; *p; p++) {
1899 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1900 return 1;
1901 }
1902 }
1903
1904 return 0;
1905}
1906
e5f38ec3 1907static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1908 const unsigned char *old_sha1, int mustexist)
1909{
c6893323 1910 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1911 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1912 unlock_ref(lock);
1913 return NULL;
1914 }
a89fccd2 1915 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1916 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1917 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1918 unlock_ref(lock);
1919 return NULL;
1920 }
1921 return lock;
1922}
1923
7155b727 1924static int remove_empty_directories(const char *file)
bc7127ef
JH
1925{
1926 /* we want to create a file but there is a directory there;
1927 * if that is an empty directory (or a directory that contains
1928 * only empty directories), remove them.
1929 */
7155b727
JS
1930 struct strbuf path;
1931 int result;
bc7127ef 1932
7155b727
JS
1933 strbuf_init(&path, 20);
1934 strbuf_addstr(&path, file);
1935
a0f4afbe 1936 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1937
1938 strbuf_release(&path);
1939
1940 return result;
bc7127ef
JH
1941}
1942
ff74f7f1
JH
1943/*
1944 * *string and *len will only be substituted, and *string returned (for
1945 * later free()ing) if the string passed in is a magic short-hand form
1946 * to name a branch.
1947 */
1948static char *substitute_branch_name(const char **string, int *len)
1949{
1950 struct strbuf buf = STRBUF_INIT;
cf99a761 1951 int ret = interpret_branch_name(*string, *len, &buf);
ff74f7f1
JH
1952
1953 if (ret == *len) {
1954 size_t size;
1955 *string = strbuf_detach(&buf, &size);
1956 *len = size;
1957 return (char *)*string;
1958 }
1959
1960 return NULL;
1961}
1962
1963int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1964{
1965 char *last_branch = substitute_branch_name(&str, &len);
1966 const char **p, *r;
1967 int refs_found = 0;
1968
1969 *ref = NULL;
1970 for (p = ref_rev_parse_rules; *p; p++) {
1971 char fullref[PATH_MAX];
1972 unsigned char sha1_from_ref[20];
1973 unsigned char *this_result;
1974 int flag;
1975
1976 this_result = refs_found ? sha1_from_ref : sha1;
1977 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1978 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1979 if (r) {
1980 if (!refs_found++)
1981 *ref = xstrdup(r);
1982 if (!warn_ambiguous_refs)
1983 break;
55956350 1984 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1985 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1986 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1987 warning("ignoring broken ref %s.", fullref);
1988 }
ff74f7f1
JH
1989 }
1990 free(last_branch);
1991 return refs_found;
1992}
1993
1994int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1995{
1996 char *last_branch = substitute_branch_name(&str, &len);
1997 const char **p;
1998 int logs_found = 0;
1999
2000 *log = NULL;
2001 for (p = ref_rev_parse_rules; *p; p++) {
2002 struct stat st;
2003 unsigned char hash[20];
2004 char path[PATH_MAX];
2005 const char *ref, *it;
2006
2007 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 2008 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
2009 if (!ref)
2010 continue;
2011 if (!stat(git_path("logs/%s", path), &st) &&
2012 S_ISREG(st.st_mode))
2013 it = path;
2014 else if (strcmp(ref, path) &&
2015 !stat(git_path("logs/%s", ref), &st) &&
2016 S_ISREG(st.st_mode))
2017 it = ref;
2018 else
2019 continue;
2020 if (!logs_found++) {
2021 *log = xstrdup(it);
2022 hashcpy(sha1, hash);
2023 }
2024 if (!warn_ambiguous_refs)
2025 break;
2026 }
2027 free(last_branch);
2028 return logs_found;
2029}
2030
dfefa935
MH
2031static struct ref_lock *lock_ref_sha1_basic(const char *refname,
2032 const unsigned char *old_sha1,
2033 int flags, int *type_p)
4bd18c43 2034{
434cd0cd 2035 char *ref_file;
dfefa935 2036 const char *orig_refname = refname;
4bd18c43 2037 struct ref_lock *lock;
5cc3cef9 2038 int last_errno = 0;
acd3b9ec 2039 int type, lflags;
4431fcc4 2040 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 2041 int missing = 0;
4bd18c43
SP
2042
2043 lock = xcalloc(1, sizeof(struct ref_lock));
2044 lock->lock_fd = -1;
2045
8d68493f 2046 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 2047 if (!refname && errno == EISDIR) {
bc7127ef
JH
2048 /* we are trying to lock foo but we used to
2049 * have foo/bar which now does not exist;
2050 * it is normal for the empty directory 'foo'
2051 * to remain.
2052 */
dfefa935 2053 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
2054 if (remove_empty_directories(ref_file)) {
2055 last_errno = errno;
dfefa935 2056 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
2057 goto error_return;
2058 }
8d68493f 2059 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 2060 }
68db31cc
SV
2061 if (type_p)
2062 *type_p = type;
dfefa935 2063 if (!refname) {
5cc3cef9 2064 last_errno = errno;
818f477c 2065 error("unable to resolve reference %s: %s",
dfefa935 2066 orig_refname, strerror(errno));
5cc3cef9 2067 goto error_return;
4bd18c43 2068 }
5bdd8d4a 2069 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
2070 /* When the ref did not exist and we are creating it,
2071 * make sure there is no existing ref that is packed
2072 * whose name begins with our refname, nor a ref whose
2073 * name is a proper prefix of our refname.
2074 */
5bdd8d4a 2075 if (missing &&
9da31cb0 2076 !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {
f475e08e 2077 last_errno = ENOTDIR;
c976d415 2078 goto error_return;
f475e08e 2079 }
22a3844e 2080
c33d5174 2081 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 2082
acd3b9ec
JH
2083 lflags = LOCK_DIE_ON_ERROR;
2084 if (flags & REF_NODEREF) {
dfefa935 2085 refname = orig_refname;
acd3b9ec
JH
2086 lflags |= LOCK_NODEREF;
2087 }
dfefa935
MH
2088 lock->ref_name = xstrdup(refname);
2089 lock->orig_ref_name = xstrdup(orig_refname);
2090 ref_file = git_path("%s", refname);
5bdd8d4a 2091 if (missing)
68db31cc
SV
2092 lock->force_write = 1;
2093 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
2094 lock->force_write = 1;
4bd18c43 2095
5cc3cef9
JH
2096 if (safe_create_leading_directories(ref_file)) {
2097 last_errno = errno;
2098 error("unable to create directory for %s", ref_file);
2099 goto error_return;
2100 }
4bd18c43 2101
acd3b9ec 2102 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 2103 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
2104
2105 error_return:
2106 unlock_ref(lock);
2107 errno = last_errno;
2108 return NULL;
4bd18c43
SP
2109}
2110
dfefa935 2111struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 2112{
53cce84c 2113 char refpath[PATH_MAX];
dfefa935 2114 if (check_refname_format(refname, 0))
4bd18c43 2115 return NULL;
dfefa935 2116 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 2117 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
2118}
2119
dfefa935 2120struct ref_lock *lock_any_ref_for_update(const char *refname,
9bbb0fa1
BK
2121 const unsigned char *old_sha1,
2122 int flags, int *type_p)
4bd18c43 2123{
dfefa935 2124 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 2125 return NULL;
9bbb0fa1 2126 return lock_ref_sha1_basic(refname, old_sha1, flags, type_p);
c0277d15
JH
2127}
2128
fec3137f
MH
2129/*
2130 * Write an entry to the packed-refs file for the specified refname.
2131 * If peeled is non-NULL, write it as the entry's peeled value.
2132 */
2133static void write_packed_entry(int fd, char *refname, unsigned char *sha1,
2134 unsigned char *peeled)
d66da478 2135{
d66da478
MH
2136 char line[PATH_MAX + 100];
2137 int len;
2138
d66da478
MH
2139 len = snprintf(line, sizeof(line), "%s %s\n",
2140 sha1_to_hex(sha1), refname);
2141 /* this should not happen but just being defensive */
2142 if (len > sizeof(line))
2143 die("too long a refname '%s'", refname);
fec3137f
MH
2144 write_or_die(fd, line, len);
2145
2146 if (peeled) {
2147 if (snprintf(line, sizeof(line), "^%s\n",
2148 sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)
2149 die("internal error");
2150 write_or_die(fd, line, PEELED_LINE_LENGTH);
2151 }
2152}
2153
7b40d396
MH
2154/*
2155 * An each_ref_entry_fn that writes the entry to a packed-refs file.
2156 */
2157static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)
2158{
2159 int *fd = cb_data;
2160 enum peel_status peel_status = peel_entry(entry, 0);
2161
2162 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
2163 error("internal error: %s is not a valid packed reference!",
2164 entry->name);
2165 write_packed_entry(*fd, entry->name, entry->u.value.sha1,
2166 peel_status == PEEL_PEELED ?
2167 entry->u.value.peeled : NULL);
2168 return 0;
2169}
2170
9f69d297
MH
2171int lock_packed_refs(int flags)
2172{
2173 struct packed_ref_cache *packed_ref_cache;
2174
9f69d297
MH
2175 if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)
2176 return -1;
5d478f5c
MH
2177 /*
2178 * Get the current packed-refs while holding the lock. If the
2179 * packed-refs file has been modified since we last read it,
2180 * this will automatically invalidate the cache and re-read
2181 * the packed-refs file.
2182 */
9f69d297
MH
2183 packed_ref_cache = get_packed_ref_cache(&ref_cache);
2184 packed_ref_cache->lock = &packlock;
4f6b83e3
MH
2185 /* Increment the reference count to prevent it from being freed: */
2186 acquire_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2187 return 0;
2188}
2189
2190int commit_packed_refs(void)
2191{
2192 struct packed_ref_cache *packed_ref_cache =
2193 get_packed_ref_cache(&ref_cache);
2194 int error = 0;
2195
2196 if (!packed_ref_cache->lock)
2197 die("internal error: packed-refs not locked");
2198 write_or_die(packed_ref_cache->lock->fd,
2199 PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
2200
2201 do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),
2202 0, write_packed_entry_fn,
2203 &packed_ref_cache->lock->fd);
2204 if (commit_lock_file(packed_ref_cache->lock))
2205 error = -1;
2206 packed_ref_cache->lock = NULL;
4f6b83e3 2207 release_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2208 return error;
2209}
2210
2211void rollback_packed_refs(void)
2212{
2213 struct packed_ref_cache *packed_ref_cache =
2214 get_packed_ref_cache(&ref_cache);
2215
2216 if (!packed_ref_cache->lock)
2217 die("internal error: packed-refs not locked");
2218 rollback_lock_file(packed_ref_cache->lock);
2219 packed_ref_cache->lock = NULL;
4f6b83e3 2220 release_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2221 clear_packed_ref_cache(&ref_cache);
2222}
2223
32d462ce
MH
2224struct ref_to_prune {
2225 struct ref_to_prune *next;
2226 unsigned char sha1[20];
2227 char name[FLEX_ARRAY];
2228};
2229
2230struct pack_refs_cb_data {
2231 unsigned int flags;
267f9a8c 2232 struct ref_dir *packed_refs;
32d462ce 2233 struct ref_to_prune *ref_to_prune;
32d462ce
MH
2234};
2235
267f9a8c
MH
2236/*
2237 * An each_ref_entry_fn that is run over loose references only. If
2238 * the loose reference can be packed, add an entry in the packed ref
2239 * cache. If the reference should be pruned, also add it to
2240 * ref_to_prune in the pack_refs_cb_data.
2241 */
2242static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)
32d462ce
MH
2243{
2244 struct pack_refs_cb_data *cb = cb_data;
f85354b5 2245 enum peel_status peel_status;
267f9a8c 2246 struct ref_entry *packed_entry;
b2a8226d 2247 int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");
32d462ce 2248
267f9a8c
MH
2249 /* ALWAYS pack tags */
2250 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)
32d462ce
MH
2251 return 0;
2252
b2a8226d
MH
2253 /* Do not pack symbolic or broken refs: */
2254 if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))
2255 return 0;
2256
267f9a8c 2257 /* Add a packed ref cache entry equivalent to the loose entry. */
f85354b5 2258 peel_status = peel_entry(entry, 1);
0f29920f 2259 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
f85354b5
MH
2260 die("internal error peeling reference %s (%s)",
2261 entry->name, sha1_to_hex(entry->u.value.sha1));
267f9a8c
MH
2262 packed_entry = find_ref(cb->packed_refs, entry->name);
2263 if (packed_entry) {
2264 /* Overwrite existing packed entry with info from loose entry */
2265 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;
2266 hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);
2267 } else {
2268 packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,
2269 REF_ISPACKED | REF_KNOWS_PEELED, 0);
2270 add_ref(cb->packed_refs, packed_entry);
2271 }
2272 hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);
32d462ce 2273
267f9a8c
MH
2274 /* Schedule the loose reference for pruning if requested. */
2275 if ((cb->flags & PACK_REFS_PRUNE)) {
12e77559 2276 int namelen = strlen(entry->name) + 1;
32d462ce 2277 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
12e77559
MH
2278 hashcpy(n->sha1, entry->u.value.sha1);
2279 strcpy(n->name, entry->name);
32d462ce
MH
2280 n->next = cb->ref_to_prune;
2281 cb->ref_to_prune = n;
2282 }
d66da478
MH
2283 return 0;
2284}
2285
32d462ce
MH
2286/*
2287 * Remove empty parents, but spare refs/ and immediate subdirs.
2288 * Note: munges *name.
2289 */
2290static void try_remove_empty_parents(char *name)
2291{
2292 char *p, *q;
2293 int i;
2294 p = name;
2295 for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */
2296 while (*p && *p != '/')
2297 p++;
2298 /* tolerate duplicate slashes; see check_refname_format() */
2299 while (*p == '/')
2300 p++;
2301 }
2302 for (q = p; *q; q++)
2303 ;
2304 while (1) {
2305 while (q > p && *q != '/')
2306 q--;
2307 while (q > p && *(q-1) == '/')
2308 q--;
2309 if (q == p)
2310 break;
2311 *q = '\0';
2312 if (rmdir(git_path("%s", name)))
2313 break;
2314 }
2315}
2316
2317/* make sure nobody touched the ref, and unlink */
2318static void prune_ref(struct ref_to_prune *r)
2319{
2320 struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
2321
2322 if (lock) {
2323 unlink_or_warn(git_path("%s", r->name));
2324 unlock_ref(lock);
2325 try_remove_empty_parents(r->name);
2326 }
2327}
2328
2329static void prune_refs(struct ref_to_prune *r)
2330{
2331 while (r) {
2332 prune_ref(r);
2333 r = r->next;
2334 }
2335}
2336
32d462ce
MH
2337int pack_refs(unsigned int flags)
2338{
32d462ce
MH
2339 struct pack_refs_cb_data cbdata;
2340
2341 memset(&cbdata, 0, sizeof(cbdata));
2342 cbdata.flags = flags;
2343
9f69d297 2344 lock_packed_refs(LOCK_DIE_ON_ERROR);
267f9a8c 2345 cbdata.packed_refs = get_packed_refs(&ref_cache);
32d462ce 2346
267f9a8c
MH
2347 do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,
2348 pack_if_possible_fn, &cbdata);
32d462ce 2349
9f69d297 2350 if (commit_packed_refs())
32d462ce 2351 die_errno("unable to overwrite old ref-pack file");
9f69d297 2352
32d462ce
MH
2353 prune_refs(cbdata.ref_to_prune);
2354 return 0;
2355}
2356
7b40d396
MH
2357/*
2358 * If entry is no longer needed in packed-refs, add it to the string
2359 * list pointed to by cb_data. Reasons for deleting entries:
2360 *
2361 * - Entry is broken.
2362 * - Entry is overridden by a loose ref.
2363 * - Entry does not point at a valid object.
2364 *
2365 * In the first and third cases, also emit an error message because these
2366 * are indications of repository corruption.
2367 */
2368static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)
c0277d15 2369{
7b40d396 2370 struct string_list *refs_to_delete = cb_data;
fec3137f 2371
ab292bc4
MH
2372 if (entry->flag & REF_ISBROKEN) {
2373 /* This shouldn't happen to packed refs. */
2374 error("%s is broken!", entry->name);
7b40d396 2375 string_list_append(refs_to_delete, entry->name);
c0277d15 2376 return 0;
ab292bc4
MH
2377 }
2378 if (!has_sha1_file(entry->u.value.sha1)) {
2379 unsigned char sha1[20];
2380 int flags;
2381
2382 if (read_ref_full(entry->name, sha1, 0, &flags))
2383 /* We should at least have found the packed ref. */
2384 die("Internal error");
7b40d396 2385 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {
ab292bc4
MH
2386 /*
2387 * This packed reference is overridden by a
2388 * loose reference, so it is OK that its value
2389 * is no longer valid; for example, it might
2390 * refer to an object that has been garbage
2391 * collected. For this purpose we don't even
2392 * care whether the loose reference itself is
2393 * invalid, broken, symbolic, etc. Silently
7b40d396 2394 * remove the packed reference.
ab292bc4 2395 */
7b40d396 2396 string_list_append(refs_to_delete, entry->name);
ab292bc4 2397 return 0;
7b40d396 2398 }
ab292bc4
MH
2399 /*
2400 * There is no overriding loose reference, so the fact
2401 * that this reference doesn't refer to a valid object
2402 * indicates some kind of repository corruption.
2403 * Report the problem, then omit the reference from
2404 * the output.
2405 */
2406 error("%s does not point to a valid object!", entry->name);
7b40d396 2407 string_list_append(refs_to_delete, entry->name);
ab292bc4
MH
2408 return 0;
2409 }
2410
d66da478
MH
2411 return 0;
2412}
2413
61cee0db 2414static int repack_without_refs(const char **refnames, int n)
c0277d15 2415{
7618fd80 2416 struct ref_dir *packed;
7b40d396
MH
2417 struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
2418 struct string_list_item *ref_to_delete;
61cee0db
BK
2419 int i, removed = 0;
2420
2421 /* Look for a packed ref */
2422 for (i = 0; i < n; i++)
2423 if (get_packed_ref(refnames[i]))
2424 break;
7618fd80 2425
61cee0db
BK
2426 /* Avoid locking if we have nothing to do */
2427 if (i == n)
2428 return 0; /* no refname exists in packed refs */
7618fd80 2429
9f69d297 2430 if (lock_packed_refs(0)) {
1b018fd9 2431 unable_to_lock_error(git_path("packed-refs"), errno);
61cee0db 2432 return error("cannot delete '%s' from packed refs", refnames[i]);
1b018fd9 2433 }
9da31cb0 2434 packed = get_packed_refs(&ref_cache);
7b40d396 2435
61cee0db
BK
2436 /* Remove refnames from the cache */
2437 for (i = 0; i < n; i++)
2438 if (remove_entry(packed, refnames[i]) != -1)
2439 removed = 1;
2440 if (!removed) {
506a760d 2441 /*
61cee0db 2442 * All packed entries disappeared while we were
506a760d
MH
2443 * acquiring the lock.
2444 */
9f69d297 2445 rollback_packed_refs();
506a760d
MH
2446 return 0;
2447 }
7b40d396 2448
61cee0db 2449 /* Remove any other accumulated cruft */
7b40d396
MH
2450 do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);
2451 for_each_string_list_item(ref_to_delete, &refs_to_delete) {
2452 if (remove_entry(packed, ref_to_delete->string) == -1)
2453 die("internal error");
2454 }
2455
61cee0db 2456 /* Write what remains */
9f69d297 2457 return commit_packed_refs();
c0277d15
JH
2458}
2459
61cee0db 2460static int repack_without_ref(const char *refname)
c0277d15 2461{
61cee0db
BK
2462 return repack_without_refs(&refname, 1);
2463}
c0277d15 2464
2ddb5d17
BK
2465static int delete_ref_loose(struct ref_lock *lock, int flag)
2466{
045a476f 2467 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 2468 /* loose */
2ddb5d17
BK
2469 int err, i = strlen(lock->lk->filename) - 5; /* .lock */
2470
547d058f
RS
2471 lock->lk->filename[i] = 0;
2472 err = unlink_or_warn(lock->lk->filename);
547d058f 2473 lock->lk->filename[i] = '.';
2ddb5d17
BK
2474 if (err && errno != ENOENT)
2475 return 1;
c0277d15 2476 }
2ddb5d17
BK
2477 return 0;
2478}
2479
eca35a25 2480int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
2481{
2482 struct ref_lock *lock;
2ddb5d17 2483 int ret = 0, flag = 0;
c0277d15 2484
547d058f 2485 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
c0277d15
JH
2486 if (!lock)
2487 return 1;
2ddb5d17 2488 ret |= delete_ref_loose(lock, flag);
691f1a28 2489
c0277d15
JH
2490 /* removing the loose one could have resurrected an earlier
2491 * packed one. Also, if it was not loose we need to repack
2492 * without it.
2493 */
b274a714 2494 ret |= repack_without_ref(lock->ref_name);
c0277d15 2495
691f1a28 2496 unlink_or_warn(git_path("logs/%s", lock->ref_name));
9da31cb0 2497 clear_loose_ref_cache(&ref_cache);
c0277d15
JH
2498 unlock_ref(lock);
2499 return ret;
4bd18c43
SP
2500}
2501
765c2258
PH
2502/*
2503 * People using contrib's git-new-workdir have .git/logs/refs ->
2504 * /some/other/path/.git/logs/refs, and that may live on another device.
2505 *
2506 * IOW, to avoid cross device rename errors, the temporary renamed log must
2507 * live into logs/refs.
2508 */
2509#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
2510
dfefa935 2511int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 2512{
c976d415
LH
2513 unsigned char sha1[20], orig_sha1[20];
2514 int flag = 0, logmoved = 0;
2515 struct ref_lock *lock;
c976d415 2516 struct stat loginfo;
dfefa935 2517 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 2518 const char *symref = NULL;
c976d415 2519
450d4c0f 2520 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 2521 return error("reflog for %s is a symlink", oldrefname);
c976d415 2522
8d68493f 2523 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 2524 if (flag & REF_ISSYMREF)
fa58186c 2525 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 2526 oldrefname);
eca35a25 2527 if (!symref)
dfefa935 2528 return error("refname %s not found", oldrefname);
c976d415 2529
9da31cb0 2530 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))
c976d415
LH
2531 return 1;
2532
9da31cb0 2533 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))
c976d415
LH
2534 return 1;
2535
dfefa935 2536 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 2537 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 2538 oldrefname, strerror(errno));
c976d415 2539
dfefa935
MH
2540 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
2541 error("unable to delete old %s", oldrefname);
c976d415
LH
2542 goto rollback;
2543 }
2544
dfefa935
MH
2545 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
2546 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 2547 if (errno==EISDIR) {
dfefa935
MH
2548 if (remove_empty_directories(git_path("%s", newrefname))) {
2549 error("Directory not empty: %s", newrefname);
c976d415
LH
2550 goto rollback;
2551 }
2552 } else {
dfefa935 2553 error("unable to delete existing %s", newrefname);
c976d415
LH
2554 goto rollback;
2555 }
2556 }
2557
dfefa935
MH
2558 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
2559 error("unable to create directory for %s", newrefname);
c976d415
LH
2560 goto rollback;
2561 }
2562
2563 retry:
dfefa935 2564 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
2565 if (errno==EISDIR || errno==ENOTDIR) {
2566 /*
2567 * rename(a, b) when b is an existing
2568 * directory ought to result in ISDIR, but
2569 * Solaris 5.8 gives ENOTDIR. Sheesh.
2570 */
dfefa935
MH
2571 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
2572 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
2573 goto rollback;
2574 }
2575 goto retry;
2576 } else {
765c2258 2577 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 2578 newrefname, strerror(errno));
c976d415
LH
2579 goto rollback;
2580 }
2581 }
2582 logmoved = log;
2583
dfefa935 2584 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 2585 if (!lock) {
dfefa935 2586 error("unable to lock %s for update", newrefname);
c976d415
LH
2587 goto rollback;
2588 }
c976d415
LH
2589 lock->force_write = 1;
2590 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 2591 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 2592 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
2593 goto rollback;
2594 }
2595
2596 return 0;
2597
2598 rollback:
dfefa935 2599 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 2600 if (!lock) {
dfefa935 2601 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
2602 goto rollbacklog;
2603 }
2604
2605 lock->force_write = 1;
2606 flag = log_all_ref_updates;
2607 log_all_ref_updates = 0;
2608 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 2609 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
2610 log_all_ref_updates = flag;
2611
2612 rollbacklog:
dfefa935 2613 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 2614 error("unable to restore logfile %s from %s: %s",
dfefa935 2615 oldrefname, newrefname, strerror(errno));
c976d415 2616 if (!logmoved && log &&
dfefa935 2617 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 2618 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 2619 oldrefname, strerror(errno));
c976d415
LH
2620
2621 return 1;
2622}
2623
435fc852 2624int close_ref(struct ref_lock *lock)
b531394d
BC
2625{
2626 if (close_lock_file(lock->lk))
2627 return -1;
2628 lock->lock_fd = -1;
2629 return 0;
2630}
2631
435fc852 2632int commit_ref(struct ref_lock *lock)
b531394d
BC
2633{
2634 if (commit_lock_file(lock->lk))
2635 return -1;
2636 lock->lock_fd = -1;
2637 return 0;
2638}
2639
e5f38ec3 2640void unlock_ref(struct ref_lock *lock)
4bd18c43 2641{
4ed7cd3a
BC
2642 /* Do not free lock->lk -- atexit() still looks at them */
2643 if (lock->lk)
2644 rollback_lock_file(lock->lk);
434cd0cd 2645 free(lock->ref_name);
1655707c 2646 free(lock->orig_ref_name);
4bd18c43
SP
2647 free(lock);
2648}
2649
0ec29a47
JH
2650/*
2651 * copy the reflog message msg to buf, which has been allocated sufficiently
2652 * large, while cleaning up the whitespaces. Especially, convert LF to space,
2653 * because reflog file is one line per entry.
2654 */
2655static int copy_msg(char *buf, const char *msg)
2656{
2657 char *cp = buf;
2658 char c;
2659 int wasspace = 1;
2660
2661 *cp++ = '\t';
2662 while ((c = *msg++)) {
2663 if (wasspace && isspace(c))
2664 continue;
2665 wasspace = isspace(c);
2666 if (wasspace)
2667 c = ' ';
2668 *cp++ = c;
2669 }
2670 while (buf < cp && isspace(cp[-1]))
2671 cp--;
2672 *cp++ = '\n';
2673 return cp - buf;
2674}
2675
dfefa935 2676int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 2677{
859c3017 2678 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 2679
dfefa935 2680 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 2681 if (log_all_ref_updates &&
dfefa935
MH
2682 (!prefixcmp(refname, "refs/heads/") ||
2683 !prefixcmp(refname, "refs/remotes/") ||
2684 !prefixcmp(refname, "refs/notes/") ||
2685 !strcmp(refname, "HEAD"))) {
157aaea5 2686 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 2687 return error("unable to create directory for %s",
157aaea5 2688 logfile);
6de08ae6
SP
2689 oflags |= O_CREAT;
2690 }
2691
157aaea5 2692 logfd = open(logfile, oflags, 0666);
6de08ae6 2693 if (logfd < 0) {
1974bf62 2694 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 2695 return 0;
3b463c3f
JH
2696
2697 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 2698 if (remove_empty_directories(logfile)) {
3b463c3f 2699 return error("There are still logs under '%s'",
157aaea5 2700 logfile);
3b463c3f 2701 }
157aaea5 2702 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
2703 }
2704
2705 if (logfd < 0)
2706 return error("Unable to append to %s: %s",
157aaea5 2707 logfile, strerror(errno));
6de08ae6
SP
2708 }
2709
157aaea5 2710 adjust_shared_perm(logfile);
859c3017
EM
2711 close(logfd);
2712 return 0;
2713}
443b92b6 2714
dfefa935 2715static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
2716 const unsigned char *new_sha1, const char *msg)
2717{
2718 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2719 unsigned maxlen, len;
2720 int msglen;
157aaea5 2721 char log_file[PATH_MAX];
859c3017
EM
2722 char *logrec;
2723 const char *committer;
2724
2725 if (log_all_ref_updates < 0)
2726 log_all_ref_updates = !is_bare_repository();
2727
dfefa935 2728 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
2729 if (result)
2730 return result;
2731
2732 logfd = open(log_file, oflags);
2733 if (logfd < 0)
2734 return 0;
0ec29a47 2735 msglen = msg ? strlen(msg) : 0;
774751a8 2736 committer = git_committer_info(0);
8ac65937
JH
2737 maxlen = strlen(committer) + msglen + 100;
2738 logrec = xmalloc(maxlen);
2739 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
2740 sha1_to_hex(old_sha1),
2741 sha1_to_hex(new_sha1),
8ac65937
JH
2742 committer);
2743 if (msglen)
0ec29a47 2744 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 2745 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 2746 free(logrec);
91c8d590 2747 if (close(logfd) != 0 || written != len)
9a13f0b7 2748 return error("Unable to append to %s", log_file);
6de08ae6
SP
2749 return 0;
2750}
2751
c3b0dec5
LT
2752static int is_branch(const char *refname)
2753{
2754 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2755}
2756
4bd18c43
SP
2757int write_ref_sha1(struct ref_lock *lock,
2758 const unsigned char *sha1, const char *logmsg)
2759{
2760 static char term = '\n';
c3b0dec5 2761 struct object *o;
4bd18c43
SP
2762
2763 if (!lock)
95fc7512 2764 return -1;
a89fccd2 2765 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
2766 unlock_ref(lock);
2767 return 0;
95fc7512 2768 }
c3b0dec5
LT
2769 o = parse_object(sha1);
2770 if (!o) {
7be8b3ba 2771 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
2772 lock->ref_name, sha1_to_hex(sha1));
2773 unlock_ref(lock);
2774 return -1;
2775 }
2776 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2777 error("Trying to write non-commit object %s to branch %s",
2778 sha1_to_hex(sha1), lock->ref_name);
2779 unlock_ref(lock);
2780 return -1;
2781 }
93822c22
AW
2782 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2783 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 2784 || close_ref(lock) < 0) {
c33d5174 2785 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
2786 unlock_ref(lock);
2787 return -1;
2788 }
9da31cb0 2789 clear_loose_ref_cache(&ref_cache);
bd104db1
NP
2790 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2791 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2792 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
2793 unlock_ref(lock);
2794 return -1;
2795 }
605fac8b
NP
2796 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2797 /*
2798 * Special hack: If a branch is updated directly and HEAD
2799 * points to it (may happen on the remote side of a push
2800 * for example) then logically the HEAD reflog should be
2801 * updated too.
2802 * A generic solution implies reverse symref information,
2803 * but finding all symrefs pointing to the given branch
2804 * would be rather costly for this rare event (the direct
2805 * update of a branch) to be worth it. So let's cheat and
2806 * check with HEAD only which should cover 99% of all usage
2807 * scenarios (even 100% of the default ones).
2808 */
2809 unsigned char head_sha1[20];
2810 int head_flag;
2811 const char *head_ref;
8cad4744 2812 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2813 if (head_ref && (head_flag & REF_ISSYMREF) &&
2814 !strcmp(head_ref, lock->ref_name))
2815 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2816 }
b531394d 2817 if (commit_ref(lock)) {
434cd0cd 2818 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2819 unlock_ref(lock);
2820 return -1;
2821 }
4bd18c43
SP
2822 unlock_ref(lock);
2823 return 0;
95fc7512 2824}
d556fae2 2825
8b5157e4
NP
2826int create_symref(const char *ref_target, const char *refs_heads_master,
2827 const char *logmsg)
41b625b0
NP
2828{
2829 const char *lockpath;
2830 char ref[1000];
2831 int fd, len, written;
a4f34cbb 2832 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2833 unsigned char old_sha1[20], new_sha1[20];
2834
2835 if (logmsg && read_ref(ref_target, old_sha1))
2836 hashclr(old_sha1);
41b625b0 2837
d48744d1
JH
2838 if (safe_create_leading_directories(git_HEAD) < 0)
2839 return error("unable to create directory for %s", git_HEAD);
2840
41b625b0
NP
2841#ifndef NO_SYMLINK_HEAD
2842 if (prefer_symlink_refs) {
2843 unlink(git_HEAD);
2844 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2845 goto done;
41b625b0
NP
2846 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2847 }
2848#endif
2849
2850 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2851 if (sizeof(ref) <= len) {
2852 error("refname too long: %s", refs_heads_master);
47fc52e2 2853 goto error_free_return;
41b625b0
NP
2854 }
2855 lockpath = mkpath("%s.lock", git_HEAD);
2856 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2857 if (fd < 0) {
2858 error("Unable to open %s for writing", lockpath);
47fc52e2 2859 goto error_free_return;
41b625b0
NP
2860 }
2861 written = write_in_full(fd, ref, len);
91c8d590 2862 if (close(fd) != 0 || written != len) {
41b625b0 2863 error("Unable to write to %s", lockpath);
47fc52e2 2864 goto error_unlink_return;
41b625b0
NP
2865 }
2866 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2867 error("Unable to create %s", git_HEAD);
47fc52e2 2868 goto error_unlink_return;
41b625b0
NP
2869 }
2870 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2871 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2872 error_unlink_return:
691f1a28 2873 unlink_or_warn(lockpath);
47fc52e2
JH
2874 error_free_return:
2875 free(git_HEAD);
2876 return -1;
41b625b0 2877 }
8b5157e4 2878
ee96d11b 2879#ifndef NO_SYMLINK_HEAD
8b5157e4 2880 done:
ee96d11b 2881#endif
8b5157e4
NP
2882 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2883 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2884
47fc52e2 2885 free(git_HEAD);
41b625b0
NP
2886 return 0;
2887}
2888
16d7cc90
JH
2889static char *ref_msg(const char *line, const char *endp)
2890{
2891 const char *ep;
16d7cc90 2892 line += 82;
182af834
PH
2893 ep = memchr(line, '\n', endp - line);
2894 if (!ep)
2895 ep = endp;
2896 return xmemdupz(line, ep - line);
16d7cc90
JH
2897}
2898
dfefa935
MH
2899int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2900 unsigned char *sha1, char **msg,
2901 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2902{
e5229042 2903 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2904 char *tz_c;
e29cb53a 2905 int logfd, tz, reccnt = 0;
d556fae2
SP
2906 struct stat st;
2907 unsigned long date;
e5229042 2908 unsigned char logged_sha1[20];
cb48cb58 2909 void *log_mapped;
dc49cd76 2910 size_t mapsz;
d556fae2 2911
dfefa935 2912 logfile = git_path("logs/%s", refname);
d556fae2
SP
2913 logfd = open(logfile, O_RDONLY, 0);
2914 if (logfd < 0)
d824cbba 2915 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2916 fstat(logfd, &st);
2917 if (!st.st_size)
2918 die("Log %s is empty.", logfile);
dc49cd76
SP
2919 mapsz = xsize_t(st.st_size);
2920 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2921 logdata = log_mapped;
d556fae2
SP
2922 close(logfd);
2923
e5229042 2924 lastrec = NULL;
d556fae2
SP
2925 rec = logend = logdata + st.st_size;
2926 while (logdata < rec) {
e29cb53a 2927 reccnt++;
d556fae2
SP
2928 if (logdata < rec && *(rec-1) == '\n')
2929 rec--;
e5229042
SP
2930 lastgt = NULL;
2931 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2932 rec--;
e5229042
SP
2933 if (*rec == '>')
2934 lastgt = rec;
2935 }
2936 if (!lastgt)
d556fae2 2937 die("Log %s is corrupt.", logfile);
e5229042 2938 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2939 if (date <= at_time || cnt == 0) {
76a44c5c 2940 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2941 if (msg)
2942 *msg = ref_msg(rec, logend);
2943 if (cutoff_time)
2944 *cutoff_time = date;
2945 if (cutoff_tz)
2946 *cutoff_tz = tz;
2947 if (cutoff_cnt)
76a44c5c 2948 *cutoff_cnt = reccnt - 1;
e5229042
SP
2949 if (lastrec) {
2950 if (get_sha1_hex(lastrec, logged_sha1))
2951 die("Log %s is corrupt.", logfile);
2952 if (get_sha1_hex(rec + 41, sha1))
2953 die("Log %s is corrupt.", logfile);
a89fccd2 2954 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2955 warning("Log %s has gap after %s.",
73013afd 2956 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2957 }
e5f38ec3
JH
2958 }
2959 else if (date == at_time) {
e5229042
SP
2960 if (get_sha1_hex(rec + 41, sha1))
2961 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2962 }
2963 else {
e5229042
SP
2964 if (get_sha1_hex(rec + 41, logged_sha1))
2965 die("Log %s is corrupt.", logfile);
a89fccd2 2966 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2967 warning("Log %s unexpectedly ended on %s.",
73013afd 2968 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2969 }
2970 }
dc49cd76 2971 munmap(log_mapped, mapsz);
d556fae2
SP
2972 return 0;
2973 }
e5229042 2974 lastrec = rec;
ab2a1a32
JH
2975 if (cnt > 0)
2976 cnt--;
d556fae2
SP
2977 }
2978
e5229042
SP
2979 rec = logdata;
2980 while (rec < logend && *rec != '>' && *rec != '\n')
2981 rec++;
2982 if (rec == logend || *rec == '\n')
d556fae2 2983 die("Log %s is corrupt.", logfile);
e5229042 2984 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2985 tz = strtoul(tz_c, NULL, 10);
2986 if (get_sha1_hex(logdata, sha1))
2987 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2988 if (is_null_sha1(sha1)) {
2989 if (get_sha1_hex(logdata + 41, sha1))
2990 die("Log %s is corrupt.", logfile);
2991 }
16d7cc90
JH
2992 if (msg)
2993 *msg = ref_msg(logdata, logend);
dc49cd76 2994 munmap(log_mapped, mapsz);
16d7cc90
JH
2995
2996 if (cutoff_time)
2997 *cutoff_time = date;
2998 if (cutoff_tz)
2999 *cutoff_tz = tz;
3000 if (cutoff_cnt)
3001 *cutoff_cnt = reccnt;
3002 return 1;
d556fae2 3003}
2ff81662 3004
9a7a183b
JH
3005static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)
3006{
3007 unsigned char osha1[20], nsha1[20];
3008 char *email_end, *message;
3009 unsigned long timestamp;
3010 int tz;
3011
3012 /* old SP new SP name <email> SP time TAB msg LF */
3013 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||
3014 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||
3015 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||
3016 !(email_end = strchr(sb->buf + 82, '>')) ||
3017 email_end[1] != ' ' ||
3018 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
3019 !message || message[0] != ' ' ||
3020 (message[1] != '+' && message[1] != '-') ||
3021 !isdigit(message[2]) || !isdigit(message[3]) ||
3022 !isdigit(message[4]) || !isdigit(message[5]))
3023 return 0; /* corrupt? */
3024 email_end[1] = '\0';
3025 tz = strtol(message + 1, NULL, 10);
3026 if (message[6] != '\t')
3027 message += 6;
3028 else
3029 message += 7;
3030 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);
3031}
3032
98f85ff4
JH
3033static char *find_beginning_of_line(char *bob, char *scan)
3034{
3035 while (bob < scan && *(--scan) != '\n')
3036 ; /* keep scanning backwards */
3037 /*
3038 * Return either beginning of the buffer, or LF at the end of
3039 * the previous line.
3040 */
3041 return scan;
3042}
3043
3044int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)
2ff81662 3045{
8ca78803 3046 struct strbuf sb = STRBUF_INIT;
98f85ff4
JH
3047 FILE *logfp;
3048 long pos;
3049 int ret = 0, at_tail = 1;
2ff81662 3050
7ae07c1b 3051 logfp = fopen(git_path("logs/%s", refname), "r");
2ff81662 3052 if (!logfp)
883d60fa 3053 return -1;
101d15e0 3054
98f85ff4
JH
3055 /* Jump to the end */
3056 if (fseek(logfp, 0, SEEK_END) < 0)
3057 return error("cannot seek back reflog for %s: %s",
3058 refname, strerror(errno));
3059 pos = ftell(logfp);
3060 while (!ret && 0 < pos) {
3061 int cnt;
3062 size_t nread;
3063 char buf[BUFSIZ];
3064 char *endp, *scanp;
3065
3066 /* Fill next block from the end */
3067 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;
3068 if (fseek(logfp, pos - cnt, SEEK_SET))
3069 return error("cannot seek back reflog for %s: %s",
3070 refname, strerror(errno));
3071 nread = fread(buf, cnt, 1, logfp);
e4ca819a 3072 if (nread != 1)
98f85ff4
JH
3073 return error("cannot read %d bytes from reflog for %s: %s",
3074 cnt, refname, strerror(errno));
3075 pos -= cnt;
3076
3077 scanp = endp = buf + cnt;
3078 if (at_tail && scanp[-1] == '\n')
3079 /* Looking at the final LF at the end of the file */
3080 scanp--;
3081 at_tail = 0;
3082
3083 while (buf < scanp) {
3084 /*
3085 * terminating LF of the previous line, or the beginning
3086 * of the buffer.
3087 */
3088 char *bp;
3089
3090 bp = find_beginning_of_line(buf, scanp);
3091
3092 if (*bp != '\n') {
3093 strbuf_splice(&sb, 0, 0, buf, endp - buf);
3094 if (pos)
3095 break; /* need to fill another block */
3096 scanp = buf - 1; /* leave loop */
3097 } else {
3098 /*
3099 * (bp + 1) thru endp is the beginning of the
3100 * current line we have in sb
3101 */
3102 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
3103 scanp = bp;
3104 endp = bp + 1;
3105 }
3106 ret = show_one_reflog_ent(&sb, fn, cb_data);
3107 strbuf_reset(&sb);
3108 if (ret)
3109 break;
9d33f7c2 3110 }
101d15e0 3111
2ff81662 3112 }
98f85ff4 3113 if (!ret && sb.len)
9a7a183b 3114 ret = show_one_reflog_ent(&sb, fn, cb_data);
98f85ff4 3115
2ff81662 3116 fclose(logfp);
8ca78803 3117 strbuf_release(&sb);
2266bf27 3118 return ret;
2ff81662 3119}
e29cb53a 3120
dfefa935 3121int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 3122{
98f85ff4
JH
3123 FILE *logfp;
3124 struct strbuf sb = STRBUF_INIT;
3125 int ret = 0;
3126
3127 logfp = fopen(git_path("logs/%s", refname), "r");
3128 if (!logfp)
3129 return -1;
101d15e0 3130
98f85ff4
JH
3131 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))
3132 ret = show_one_reflog_ent(&sb, fn, cb_data);
3133 fclose(logfp);
3134 strbuf_release(&sb);
3135 return ret;
3136}
989c0e5d
MH
3137/*
3138 * Call fn for each reflog in the namespace indicated by name. name
3139 * must be empty or end with '/'. Name will be used as a scratch
3140 * space, but its contents will be restored before return.
3141 */
3142static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 3143{
989c0e5d 3144 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 3145 int retval = 0;
93c603fc 3146 struct dirent *de;
989c0e5d 3147 int oldlen = name->len;
eb8381c8 3148
93c603fc 3149 if (!d)
989c0e5d 3150 return name->len ? errno : 0;
eb8381c8 3151
93c603fc
MH
3152 while ((de = readdir(d)) != NULL) {
3153 struct stat st;
eb8381c8 3154
93c603fc
MH
3155 if (de->d_name[0] == '.')
3156 continue;
93c603fc
MH
3157 if (has_extension(de->d_name, ".lock"))
3158 continue;
989c0e5d
MH
3159 strbuf_addstr(name, de->d_name);
3160 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
3161 ; /* silently ignore */
93c603fc 3162 } else {
eb8381c8 3163 if (S_ISDIR(st.st_mode)) {
989c0e5d
MH
3164 strbuf_addch(name, '/');
3165 retval = do_for_each_reflog(name, fn, cb_data);
eb8381c8
NP
3166 } else {
3167 unsigned char sha1[20];
989c0e5d
MH
3168 if (read_ref_full(name->buf, sha1, 0, NULL))
3169 retval = error("bad ref for %s", name->buf);
eb8381c8 3170 else
989c0e5d 3171 retval = fn(name->buf, sha1, 0, cb_data);
eb8381c8
NP
3172 }
3173 if (retval)
3174 break;
3175 }
989c0e5d 3176 strbuf_setlen(name, oldlen);
eb8381c8 3177 }
93c603fc 3178 closedir(d);
eb8381c8
NP
3179 return retval;
3180}
3181
3182int for_each_reflog(each_ref_fn fn, void *cb_data)
3183{
989c0e5d
MH
3184 int retval;
3185 struct strbuf name;
3186 strbuf_init(&name, PATH_MAX);
3187 retval = do_for_each_reflog(&name, fn, cb_data);
3188 strbuf_release(&name);
3189 return retval;
eb8381c8 3190}
3d9f037c 3191
4738a333
BK
3192static struct ref_lock *update_ref_lock(const char *refname,
3193 const unsigned char *oldval,
3194 int flags, int *type_p,
3195 enum action_on_err onerr)
3d9f037c 3196{
4738a333
BK
3197 struct ref_lock *lock;
3198 lock = lock_any_ref_for_update(refname, oldval, flags, type_p);
3d9f037c
CR
3199 if (!lock) {
3200 const char *str = "Cannot lock the ref '%s'.";
3201 switch (onerr) {
3202 case MSG_ON_ERR: error(str, refname); break;
3203 case DIE_ON_ERR: die(str, refname); break;
3204 case QUIET_ON_ERR: break;
3205 }
3d9f037c 3206 }
4738a333
BK
3207 return lock;
3208}
3209
3210static int update_ref_write(const char *action, const char *refname,
3211 const unsigned char *sha1, struct ref_lock *lock,
3212 enum action_on_err onerr)
3213{
3d9f037c
CR
3214 if (write_ref_sha1(lock, sha1, action) < 0) {
3215 const char *str = "Cannot update the ref '%s'.";
3216 switch (onerr) {
3217 case MSG_ON_ERR: error(str, refname); break;
3218 case DIE_ON_ERR: die(str, refname); break;
3219 case QUIET_ON_ERR: break;
3220 }
3221 return 1;
3222 }
3223 return 0;
3224}
cda69f48 3225
4738a333
BK
3226int update_ref(const char *action, const char *refname,
3227 const unsigned char *sha1, const unsigned char *oldval,
3228 int flags, enum action_on_err onerr)
3229{
3230 struct ref_lock *lock;
ce1e8462 3231 lock = update_ref_lock(refname, oldval, flags, NULL, onerr);
4738a333
BK
3232 if (!lock)
3233 return 1;
3234 return update_ref_write(action, refname, sha1, lock, onerr);
3235}
3236
98aee92d
BK
3237static int ref_update_compare(const void *r1, const void *r2)
3238{
3239 const struct ref_update * const *u1 = r1;
3240 const struct ref_update * const *u2 = r2;
3241 return strcmp((*u1)->ref_name, (*u2)->ref_name);
3242}
3243
3244static int ref_update_reject_duplicates(struct ref_update **updates, int n,
3245 enum action_on_err onerr)
3246{
3247 int i;
3248 for (i = 1; i < n; i++)
3249 if (!strcmp(updates[i - 1]->ref_name, updates[i]->ref_name)) {
3250 const char *str =
3251 "Multiple updates for ref '%s' not allowed.";
3252 switch (onerr) {
3253 case MSG_ON_ERR:
3254 error(str, updates[i]->ref_name); break;
3255 case DIE_ON_ERR:
3256 die(str, updates[i]->ref_name); break;
3257 case QUIET_ON_ERR:
3258 break;
3259 }
3260 return 1;
3261 }
3262 return 0;
3263}
3264
3265int update_refs(const char *action, const struct ref_update **updates_orig,
3266 int n, enum action_on_err onerr)
3267{
3268 int ret = 0, delnum = 0, i;
3269 struct ref_update **updates;
3270 int *types;
3271 struct ref_lock **locks;
3272 const char **delnames;
3273
3274 if (!updates_orig || !n)
3275 return 0;
3276
3277 /* Allocate work space */
3278 updates = xmalloc(sizeof(*updates) * n);
3279 types = xmalloc(sizeof(*types) * n);
3280 locks = xcalloc(n, sizeof(*locks));
3281 delnames = xmalloc(sizeof(*delnames) * n);
3282
3283 /* Copy, sort, and reject duplicate refs */
3284 memcpy(updates, updates_orig, sizeof(*updates) * n);
3285 qsort(updates, n, sizeof(*updates), ref_update_compare);
3286 ret = ref_update_reject_duplicates(updates, n, onerr);
3287 if (ret)
3288 goto cleanup;
3289
3290 /* Acquire all locks while verifying old values */
3291 for (i = 0; i < n; i++) {
3292 locks[i] = update_ref_lock(updates[i]->ref_name,
3293 (updates[i]->have_old ?
3294 updates[i]->old_sha1 : NULL),
3295 updates[i]->flags,
3296 &types[i], onerr);
3297 if (!locks[i]) {
3298 ret = 1;
3299 goto cleanup;
3300 }
3301 }
3302
3303 /* Perform updates first so live commits remain referenced */
3304 for (i = 0; i < n; i++)
3305 if (!is_null_sha1(updates[i]->new_sha1)) {
3306 ret = update_ref_write(action,
3307 updates[i]->ref_name,
3308 updates[i]->new_sha1,
3309 locks[i], onerr);
3310 locks[i] = NULL; /* freed by update_ref_write */
3311 if (ret)
3312 goto cleanup;
3313 }
3314
3315 /* Perform deletes now that updates are safely completed */
3316 for (i = 0; i < n; i++)
3317 if (locks[i]) {
3318 delnames[delnum++] = locks[i]->ref_name;
3319 ret |= delete_ref_loose(locks[i], types[i]);
3320 }
3321 ret |= repack_without_refs(delnames, delnum);
3322 for (i = 0; i < delnum; i++)
3323 unlink_or_warn(git_path("logs/%s", delnames[i]));
3324 clear_loose_ref_cache(&ref_cache);
3325
3326cleanup:
3327 for (i = 0; i < n; i++)
3328 if (locks[i])
3329 unlock_ref(locks[i]);
3330 free(updates);
3331 free(types);
3332 free(locks);
3333 free(delnames);
3334 return ret;
3335}
3336
7c2b3029
JK
3337/*
3338 * generate a format suitable for scanf from a ref_rev_parse_rules
3339 * rule, that is replace the "%.*s" spec with a "%s" spec
3340 */
3341static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
3342{
3343 char *spec;
3344
3345 spec = strstr(rule, "%.*s");
3346 if (!spec || strstr(spec + 4, "%.*s"))
3347 die("invalid rule in ref_rev_parse_rules: %s", rule);
3348
3349 /* copy all until spec */
3350 strncpy(scanf_fmt, rule, spec - rule);
3351 scanf_fmt[spec - rule] = '\0';
3352 /* copy new spec */
3353 strcat(scanf_fmt, "%s");
3354 /* copy remaining rule */
3355 strcat(scanf_fmt, spec + 4);
3356
3357 return;
3358}
3359
dfefa935 3360char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
3361{
3362 int i;
3363 static char **scanf_fmts;
3364 static int nr_rules;
3365 char *short_name;
3366
3367 /* pre generate scanf formats from ref_rev_parse_rules[] */
3368 if (!nr_rules) {
3369 size_t total_len = 0;
3370
3371 /* the rule list is NULL terminated, count them first */
a4165851 3372 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
7c2b3029
JK
3373 /* no +1 because strlen("%s") < strlen("%.*s") */
3374 total_len += strlen(ref_rev_parse_rules[nr_rules]);
3375
3376 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
3377
3378 total_len = 0;
3379 for (i = 0; i < nr_rules; i++) {
3380 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
3381 + total_len;
3382 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
3383 total_len += strlen(ref_rev_parse_rules[i]);
3384 }
3385 }
3386
3387 /* bail out if there are no rules */
3388 if (!nr_rules)
dfefa935 3389 return xstrdup(refname);
7c2b3029 3390
dfefa935
MH
3391 /* buffer for scanf result, at most refname must fit */
3392 short_name = xstrdup(refname);
7c2b3029
JK
3393
3394 /* skip first rule, it will always match */
3395 for (i = nr_rules - 1; i > 0 ; --i) {
3396 int j;
6e7b3309 3397 int rules_to_fail = i;
7c2b3029
JK
3398 int short_name_len;
3399
dfefa935 3400 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
3401 continue;
3402
3403 short_name_len = strlen(short_name);
3404
6e7b3309
BW
3405 /*
3406 * in strict mode, all (except the matched one) rules
3407 * must fail to resolve to a valid non-ambiguous ref
3408 */
3409 if (strict)
3410 rules_to_fail = nr_rules;
3411
7c2b3029
JK
3412 /*
3413 * check if the short name resolves to a valid ref,
3414 * but use only rules prior to the matched one
3415 */
6e7b3309 3416 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 3417 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
3418 char refname[PATH_MAX];
3419
6e7b3309
BW
3420 /* skip matched rule */
3421 if (i == j)
3422 continue;
3423
7c2b3029
JK
3424 /*
3425 * the short name is ambiguous, if it resolves
3426 * (with this previous rule) to a valid ref
3427 * read_ref() returns 0 on success
3428 */
3429 mksnpath(refname, sizeof(refname),
3430 rule, short_name_len, short_name);
c6893323 3431 if (ref_exists(refname))
7c2b3029
JK
3432 break;
3433 }
3434
3435 /*
3436 * short name is non-ambiguous if all previous rules
3437 * haven't resolved to a valid ref
3438 */
6e7b3309 3439 if (j == rules_to_fail)
7c2b3029
JK
3440 return short_name;
3441 }
3442
3443 free(short_name);
dfefa935 3444 return xstrdup(refname);
7c2b3029 3445}
daebaa78
JH
3446
3447static struct string_list *hide_refs;
3448
3449int parse_hide_refs_config(const char *var, const char *value, const char *section)
3450{
3451 if (!strcmp("transfer.hiderefs", var) ||
3452 /* NEEDSWORK: use parse_config_key() once both are merged */
3453 (!prefixcmp(var, section) && var[strlen(section)] == '.' &&
3454 !strcmp(var + strlen(section), ".hiderefs"))) {
3455 char *ref;
3456 int len;
3457
3458 if (!value)
3459 return config_error_nonbool(var);
3460 ref = xstrdup(value);
3461 len = strlen(ref);
3462 while (len && ref[len - 1] == '/')
3463 ref[--len] = '\0';
3464 if (!hide_refs) {
3465 hide_refs = xcalloc(1, sizeof(*hide_refs));
3466 hide_refs->strdup_strings = 1;
3467 }
3468 string_list_append(hide_refs, ref);
3469 }
3470 return 0;
3471}
3472
3473int ref_is_hidden(const char *refname)
3474{
3475 struct string_list_item *item;
3476
3477 if (!hide_refs)
3478 return 0;
3479 for_each_string_list_item(item, hide_refs) {
3480 int len;
3481 if (prefixcmp(refname, item->string))
3482 continue;
3483 len = strlen(item->string);
3484 if (!refname[len] || refname[len] == '/')
3485 return 1;
3486 }
3487 return 0;
3488}