for_each_ref: load all loose refs before packed refs
[git/git.git] / refs.c
CommitLineData
95fc7512 1#include "cache.h"
85023577 2#include "refs.h"
cf0adba7
JH
3#include "object.h"
4#include "tag.h"
7155b727 5#include "dir.h"
daebaa78 6#include "string-list.h"
95fc7512 7
bc5fd6d3
MH
8/*
9 * Make sure "ref" is something reasonable to have under ".git/refs/";
10 * We do not like it if:
11 *
12 * - any path component of it begins with ".", or
13 * - it has double dots "..", or
14 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
15 * - it ends with a "/".
16 * - it ends with ".lock"
17 * - it contains a "\" (backslash)
18 */
f4204ab9 19
bc5fd6d3
MH
20/* Return true iff ch is not allowed in reference names. */
21static inline int bad_ref_char(int ch)
22{
23 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
24 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
25 return 1;
26 /* 2.13 Pattern Matching Notation */
27 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
28 return 1;
29 return 0;
30}
31
32/*
33 * Try to read one refname component from the front of refname. Return
34 * the length of the component found, or -1 if the component is not
35 * legal.
36 */
37static int check_refname_component(const char *refname, int flags)
38{
39 const char *cp;
40 char last = '\0';
41
42 for (cp = refname; ; cp++) {
43 char ch = *cp;
44 if (ch == '\0' || ch == '/')
45 break;
46 if (bad_ref_char(ch))
47 return -1; /* Illegal character in refname. */
48 if (last == '.' && ch == '.')
49 return -1; /* Refname contains "..". */
50 if (last == '@' && ch == '{')
51 return -1; /* Refname contains "@{". */
52 last = ch;
53 }
54 if (cp == refname)
dac529e4 55 return 0; /* Component has zero length. */
bc5fd6d3
MH
56 if (refname[0] == '.') {
57 if (!(flags & REFNAME_DOT_COMPONENT))
58 return -1; /* Component starts with '.'. */
59 /*
60 * Even if leading dots are allowed, don't allow "."
61 * as a component (".." is prevented by a rule above).
62 */
63 if (refname[1] == '\0')
64 return -1; /* Component equals ".". */
65 }
66 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
67 return -1; /* Refname ends with ".lock". */
68 return cp - refname;
69}
70
71int check_refname_format(const char *refname, int flags)
72{
73 int component_len, component_count = 0;
74
cdfd9483
FC
75 if (!strcmp(refname, "@"))
76 /* Refname is a single character '@'. */
77 return -1;
78
bc5fd6d3
MH
79 while (1) {
80 /* We are at the start of a path component. */
81 component_len = check_refname_component(refname, flags);
dac529e4 82 if (component_len <= 0) {
bc5fd6d3
MH
83 if ((flags & REFNAME_REFSPEC_PATTERN) &&
84 refname[0] == '*' &&
85 (refname[1] == '\0' || refname[1] == '/')) {
86 /* Accept one wildcard as a full refname component. */
87 flags &= ~REFNAME_REFSPEC_PATTERN;
88 component_len = 1;
89 } else {
90 return -1;
91 }
92 }
93 component_count++;
94 if (refname[component_len] == '\0')
95 break;
96 /* Skip to next component. */
97 refname += component_len + 1;
98 }
99
100 if (refname[component_len - 1] == '.')
101 return -1; /* Refname ends with '.'. */
102 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
103 return -1; /* Refname has only one component. */
104 return 0;
105}
106
107struct ref_entry;
e1e22e37 108
28e6a34e
MH
109/*
110 * Information used (along with the information in ref_entry) to
111 * describe a single cached reference. This data structure only
112 * occurs embedded in a union in struct ref_entry, and only when
113 * (ref_entry->flag & REF_DIR) is zero.
114 */
593f1bb8 115struct ref_value {
6c6f58df
MH
116 /*
117 * The name of the object to which this reference resolves
118 * (which may be a tag object). If REF_ISBROKEN, this is
119 * null. If REF_ISSYMREF, then this is the name of the object
120 * referred to by the last reference in the symlink chain.
121 */
593f1bb8 122 unsigned char sha1[20];
6c6f58df
MH
123
124 /*
125 * If REF_KNOWS_PEELED, then this field holds the peeled value
126 * of this reference, or null if the reference is known not to
2312a793
MH
127 * be peelable. See the documentation for peel_ref() for an
128 * exact definition of "peelable".
6c6f58df 129 */
593f1bb8
MH
130 unsigned char peeled[20];
131};
132
f006c42a
MH
133struct ref_cache;
134
28e6a34e
MH
135/*
136 * Information used (along with the information in ref_entry) to
137 * describe a level in the hierarchy of references. This data
138 * structure only occurs embedded in a union in struct ref_entry, and
139 * only when (ref_entry.flag & REF_DIR) is set. In that case,
140 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
141 * in the directory have already been read:
142 *
143 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
144 * or packed references, already read.
145 *
146 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
147 * references that hasn't been read yet (nor has any of its
148 * subdirectories).
149 *
150 * Entries within a directory are stored within a growable array of
151 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
152 * sorted are sorted by their component name in strcmp() order and the
153 * remaining entries are unsorted.
154 *
155 * Loose references are read lazily, one directory at a time. When a
156 * directory of loose references is read, then all of the references
157 * in that directory are stored, and REF_INCOMPLETE stubs are created
158 * for any subdirectories, but the subdirectories themselves are not
159 * read. The reading is triggered by get_ref_dir().
160 */
d3177275 161struct ref_dir {
e9c4c111 162 int nr, alloc;
e6ed3ca6
MH
163
164 /*
165 * Entries with index 0 <= i < sorted are sorted by name. New
166 * entries are appended to the list unsorted, and are sorted
167 * only when required; thus we avoid the need to sort the list
168 * after the addition of every reference.
169 */
170 int sorted;
171
f006c42a
MH
172 /* A pointer to the ref_cache that contains this ref_dir. */
173 struct ref_cache *ref_cache;
174
d3177275 175 struct ref_entry **entries;
e9c4c111
JP
176};
177
89df9c84
MH
178/*
179 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01,
180 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see
181 * refs.h.
182 */
183
184/*
185 * The field ref_entry->u.value.peeled of this value entry contains
186 * the correct peeled value for the reference, which might be
187 * null_sha1 if the reference is not a tag or if it is broken.
188 */
432ad41e 189#define REF_KNOWS_PEELED 0x08
28e6a34e
MH
190
191/* ref_entry represents a directory of references */
432ad41e 192#define REF_DIR 0x10
cf0adba7 193
28e6a34e
MH
194/*
195 * Entry has not yet been read from disk (used only for REF_DIR
196 * entries representing loose references)
197 */
198#define REF_INCOMPLETE 0x20
199
432ad41e
MH
200/*
201 * A ref_entry represents either a reference or a "subdirectory" of
28e6a34e
MH
202 * references.
203 *
204 * Each directory in the reference namespace is represented by a
205 * ref_entry with (flags & REF_DIR) set and containing a subdir member
206 * that holds the entries in that directory that have been read so
207 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
208 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
209 * used for loose reference directories.
210 *
211 * References are represented by a ref_entry with (flags & REF_DIR)
212 * unset and a value member that describes the reference's value. The
213 * flag member is at the ref_entry level, but it is also needed to
214 * interpret the contents of the value field (in other words, a
215 * ref_value object is not very much use without the enclosing
216 * ref_entry).
432ad41e
MH
217 *
218 * Reference names cannot end with slash and directories' names are
219 * always stored with a trailing slash (except for the top-level
220 * directory, which is always denoted by ""). This has two nice
221 * consequences: (1) when the entries in each subdir are sorted
222 * lexicographically by name (as they usually are), the references in
223 * a whole tree can be generated in lexicographic order by traversing
224 * the tree in left-to-right, depth-first order; (2) the names of
225 * references and subdirectories cannot conflict, and therefore the
226 * presence of an empty subdirectory does not block the creation of a
227 * similarly-named reference. (The fact that reference names with the
228 * same leading components can conflict *with each other* is a
229 * separate issue that is regulated by is_refname_available().)
230 *
231 * Please note that the name field contains the fully-qualified
232 * reference (or subdirectory) name. Space could be saved by only
233 * storing the relative names. But that would require the full names
234 * to be generated on the fly when iterating in do_for_each_ref(), and
235 * would break callback functions, who have always been able to assume
236 * that the name strings that they are passed will not be freed during
237 * the iteration.
238 */
bc5fd6d3
MH
239struct ref_entry {
240 unsigned char flag; /* ISSYMREF? ISPACKED? */
593f1bb8 241 union {
432ad41e
MH
242 struct ref_value value; /* if not (flags&REF_DIR) */
243 struct ref_dir subdir; /* if (flags&REF_DIR) */
593f1bb8 244 } u;
432ad41e
MH
245 /*
246 * The full name of the reference (e.g., "refs/heads/master")
247 * or the full name of the directory with a trailing slash
248 * (e.g., "refs/heads/"):
249 */
bc5fd6d3
MH
250 char name[FLEX_ARRAY];
251};
e1e22e37 252
28e6a34e
MH
253static void read_loose_refs(const char *dirname, struct ref_dir *dir);
254
d7826d54
MH
255static struct ref_dir *get_ref_dir(struct ref_entry *entry)
256{
28e6a34e 257 struct ref_dir *dir;
d7826d54 258 assert(entry->flag & REF_DIR);
28e6a34e
MH
259 dir = &entry->u.subdir;
260 if (entry->flag & REF_INCOMPLETE) {
261 read_loose_refs(entry->name, dir);
262 entry->flag &= ~REF_INCOMPLETE;
263 }
264 return dir;
d7826d54
MH
265}
266
cddc4258
MH
267static struct ref_entry *create_ref_entry(const char *refname,
268 const unsigned char *sha1, int flag,
269 int check_name)
e1e22e37
LT
270{
271 int len;
cddc4258 272 struct ref_entry *ref;
e1e22e37 273
09116a1c 274 if (check_name &&
dfefa935
MH
275 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
276 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
277 len = strlen(refname) + 1;
278 ref = xmalloc(sizeof(struct ref_entry) + len);
593f1bb8
MH
279 hashcpy(ref->u.value.sha1, sha1);
280 hashclr(ref->u.value.peeled);
cddc4258
MH
281 memcpy(ref->name, refname, len);
282 ref->flag = flag;
283 return ref;
284}
285
432ad41e
MH
286static void clear_ref_dir(struct ref_dir *dir);
287
732134ed
MH
288static void free_ref_entry(struct ref_entry *entry)
289{
27b5587c
MH
290 if (entry->flag & REF_DIR) {
291 /*
292 * Do not use get_ref_dir() here, as that might
293 * trigger the reading of loose refs.
294 */
295 clear_ref_dir(&entry->u.subdir);
296 }
732134ed
MH
297 free(entry);
298}
299
432ad41e
MH
300/*
301 * Add a ref_entry to the end of dir (unsorted). Entry is always
302 * stored directly in dir; no recursion into subdirectories is
303 * done.
304 */
305static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
cddc4258 306{
432ad41e
MH
307 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
308 dir->entries[dir->nr++] = entry;
654ad400
MH
309 /* optimize for the case that entries are added in order */
310 if (dir->nr == 1 ||
311 (dir->nr == dir->sorted + 1 &&
312 strcmp(dir->entries[dir->nr - 2]->name,
313 dir->entries[dir->nr - 1]->name) < 0))
314 dir->sorted = dir->nr;
c774aab9
JP
315}
316
432ad41e
MH
317/*
318 * Clear and free all entries in dir, recursively.
319 */
d3177275 320static void clear_ref_dir(struct ref_dir *dir)
bc5fd6d3
MH
321{
322 int i;
d3177275
MH
323 for (i = 0; i < dir->nr; i++)
324 free_ref_entry(dir->entries[i]);
325 free(dir->entries);
326 dir->sorted = dir->nr = dir->alloc = 0;
327 dir->entries = NULL;
bc5fd6d3
MH
328}
329
432ad41e
MH
330/*
331 * Create a struct ref_entry object for the specified dirname.
332 * dirname is the name of the directory with a trailing slash (e.g.,
333 * "refs/heads/") or "" for the top-level directory.
334 */
f006c42a 335static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
b9146f51
RS
336 const char *dirname, size_t len,
337 int incomplete)
432ad41e
MH
338{
339 struct ref_entry *direntry;
432ad41e 340 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
b9146f51
RS
341 memcpy(direntry->name, dirname, len);
342 direntry->name[len] = '\0';
f006c42a 343 direntry->u.subdir.ref_cache = ref_cache;
28e6a34e 344 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
432ad41e
MH
345 return direntry;
346}
347
e9c4c111 348static int ref_entry_cmp(const void *a, const void *b)
c774aab9 349{
e9c4c111
JP
350 struct ref_entry *one = *(struct ref_entry **)a;
351 struct ref_entry *two = *(struct ref_entry **)b;
352 return strcmp(one->name, two->name);
353}
c774aab9 354
d3177275 355static void sort_ref_dir(struct ref_dir *dir);
bc5fd6d3 356
e1980c9d
JH
357struct string_slice {
358 size_t len;
359 const char *str;
360};
361
362static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
363{
c971ddfd
RS
364 const struct string_slice *key = key_;
365 const struct ref_entry *ent = *(const struct ref_entry * const *)ent_;
366 int cmp = strncmp(key->str, ent->name, key->len);
e1980c9d
JH
367 if (cmp)
368 return cmp;
c971ddfd 369 return '\0' - (unsigned char)ent->name[key->len];
e1980c9d
JH
370}
371
432ad41e 372/*
9fc0a648
MH
373 * Return the index of the entry with the given refname from the
374 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if
375 * no such entry is found. dir must already be complete.
432ad41e 376 */
9fc0a648 377static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len)
bc5fd6d3 378{
e1980c9d
JH
379 struct ref_entry **r;
380 struct string_slice key;
bc5fd6d3 381
432ad41e 382 if (refname == NULL || !dir->nr)
9fc0a648 383 return -1;
bc5fd6d3 384
d3177275 385 sort_ref_dir(dir);
e1980c9d
JH
386 key.len = len;
387 key.str = refname;
388 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
389 ref_entry_cmp_sslice);
bc5fd6d3
MH
390
391 if (r == NULL)
9fc0a648 392 return -1;
bc5fd6d3 393
9fc0a648 394 return r - dir->entries;
bc5fd6d3
MH
395}
396
f348ac92
MH
397/*
398 * Search for a directory entry directly within dir (without
399 * recursing). Sort dir if necessary. subdirname must be a directory
400 * name (i.e., end in '/'). If mkdir is set, then create the
401 * directory if it is missing; otherwise, return NULL if the desired
28e6a34e 402 * directory cannot be found. dir must already be complete.
f348ac92 403 */
3f3aa1bc 404static struct ref_dir *search_for_subdir(struct ref_dir *dir,
dd02e728
RS
405 const char *subdirname, size_t len,
406 int mkdir)
f348ac92 407{
9fc0a648
MH
408 int entry_index = search_ref_dir(dir, subdirname, len);
409 struct ref_entry *entry;
410 if (entry_index == -1) {
f348ac92
MH
411 if (!mkdir)
412 return NULL;
28e6a34e
MH
413 /*
414 * Since dir is complete, the absence of a subdir
415 * means that the subdir really doesn't exist;
416 * therefore, create an empty record for it but mark
417 * the record complete.
418 */
b9146f51 419 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
f348ac92 420 add_entry_to_dir(dir, entry);
9fc0a648
MH
421 } else {
422 entry = dir->entries[entry_index];
f348ac92 423 }
3f3aa1bc 424 return get_ref_dir(entry);
f348ac92
MH
425}
426
432ad41e
MH
427/*
428 * If refname is a reference name, find the ref_dir within the dir
429 * tree that should hold refname. If refname is a directory name
430 * (i.e., ends in '/'), then return that ref_dir itself. dir must
28e6a34e
MH
431 * represent the top-level directory and must already be complete.
432 * Sort ref_dirs and recurse into subdirectories as necessary. If
433 * mkdir is set, then create any missing directories; otherwise,
434 * return NULL if the desired directory cannot be found.
432ad41e
MH
435 */
436static struct ref_dir *find_containing_dir(struct ref_dir *dir,
437 const char *refname, int mkdir)
438{
5fa04418 439 const char *slash;
5fa04418 440 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
dd02e728 441 size_t dirnamelen = slash - refname + 1;
3f3aa1bc 442 struct ref_dir *subdir;
dd02e728 443 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
663c1295
JH
444 if (!subdir) {
445 dir = NULL;
f348ac92 446 break;
432ad41e 447 }
3f3aa1bc 448 dir = subdir;
432ad41e
MH
449 }
450
432ad41e
MH
451 return dir;
452}
453
454/*
455 * Find the value entry with the given name in dir, sorting ref_dirs
456 * and recursing into subdirectories as necessary. If the name is not
457 * found or it corresponds to a directory entry, return NULL.
458 */
459static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
460{
9fc0a648 461 int entry_index;
432ad41e
MH
462 struct ref_entry *entry;
463 dir = find_containing_dir(dir, refname, 0);
464 if (!dir)
465 return NULL;
9fc0a648
MH
466 entry_index = search_ref_dir(dir, refname, strlen(refname));
467 if (entry_index == -1)
468 return NULL;
469 entry = dir->entries[entry_index];
470 return (entry->flag & REF_DIR) ? NULL : entry;
432ad41e
MH
471}
472
506a760d
MH
473/*
474 * Remove the entry with the given name from dir, recursing into
475 * subdirectories as necessary. If refname is the name of a directory
476 * (i.e., ends with '/'), then remove the directory and its contents.
477 * If the removal was successful, return the number of entries
478 * remaining in the directory entry that contained the deleted entry.
479 * If the name was not found, return -1. Please note that this
480 * function only deletes the entry from the cache; it does not delete
481 * it from the filesystem or ensure that other cache entries (which
482 * might be symbolic references to the removed entry) are updated.
483 * Nor does it remove any containing dir entries that might be made
484 * empty by the removal. dir must represent the top-level directory
485 * and must already be complete.
486 */
487static int remove_entry(struct ref_dir *dir, const char *refname)
488{
489 int refname_len = strlen(refname);
490 int entry_index;
491 struct ref_entry *entry;
492 int is_dir = refname[refname_len - 1] == '/';
493 if (is_dir) {
494 /*
495 * refname represents a reference directory. Remove
496 * the trailing slash; otherwise we will get the
497 * directory *representing* refname rather than the
498 * one *containing* it.
499 */
500 char *dirname = xmemdupz(refname, refname_len - 1);
501 dir = find_containing_dir(dir, dirname, 0);
502 free(dirname);
503 } else {
504 dir = find_containing_dir(dir, refname, 0);
505 }
506 if (!dir)
507 return -1;
508 entry_index = search_ref_dir(dir, refname, refname_len);
509 if (entry_index == -1)
510 return -1;
511 entry = dir->entries[entry_index];
512
513 memmove(&dir->entries[entry_index],
514 &dir->entries[entry_index + 1],
515 (dir->nr - entry_index - 1) * sizeof(*dir->entries)
516 );
517 dir->nr--;
518 if (dir->sorted > entry_index)
519 dir->sorted--;
520 free_ref_entry(entry);
521 return dir->nr;
432ad41e
MH
522}
523
524/*
525 * Add a ref_entry to the ref_dir (unsorted), recursing into
526 * subdirectories as necessary. dir must represent the top-level
527 * directory. Return 0 on success.
528 */
529static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
530{
531 dir = find_containing_dir(dir, ref->name, 1);
532 if (!dir)
533 return -1;
534 add_entry_to_dir(dir, ref);
535 return 0;
536}
537
202a56a9
MH
538/*
539 * Emit a warning and return true iff ref1 and ref2 have the same name
540 * and the same sha1. Die if they have the same name but different
541 * sha1s.
542 */
543static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
544{
432ad41e 545 if (strcmp(ref1->name, ref2->name))
202a56a9 546 return 0;
432ad41e
MH
547
548 /* Duplicate name; make sure that they don't conflict: */
549
550 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
551 /* This is impossible by construction */
552 die("Reference directory conflict: %s", ref1->name);
553
554 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
555 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
556
557 warning("Duplicated ref: %s", ref1->name);
558 return 1;
202a56a9
MH
559}
560
e6ed3ca6 561/*
432ad41e
MH
562 * Sort the entries in dir non-recursively (if they are not already
563 * sorted) and remove any duplicate entries.
e6ed3ca6 564 */
d3177275 565static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 566{
202a56a9 567 int i, j;
81a79d8e 568 struct ref_entry *last = NULL;
c774aab9 569
e6ed3ca6
MH
570 /*
571 * This check also prevents passing a zero-length array to qsort(),
572 * which is a problem on some platforms.
573 */
d3177275 574 if (dir->sorted == dir->nr)
e9c4c111 575 return;
c774aab9 576
d3177275 577 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 578
81a79d8e
MH
579 /* Remove any duplicates: */
580 for (i = 0, j = 0; j < dir->nr; j++) {
581 struct ref_entry *entry = dir->entries[j];
582 if (last && is_dup_ref(last, entry))
583 free_ref_entry(entry);
584 else
585 last = dir->entries[i++] = entry;
e9c4c111 586 }
81a79d8e 587 dir->sorted = dir->nr = i;
e9c4c111 588}
c774aab9 589
fcce1703
MH
590/* Include broken references in a do_for_each_ref*() iteration: */
591#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
c774aab9 592
662428f4
MH
593/*
594 * Return true iff the reference described by entry can be resolved to
595 * an object in the database. Emit a warning if the referred-to
596 * object does not exist.
597 */
598static int ref_resolves_to_object(struct ref_entry *entry)
599{
600 if (entry->flag & REF_ISBROKEN)
601 return 0;
602 if (!has_sha1_file(entry->u.value.sha1)) {
603 error("%s does not point to a valid object!", entry->name);
604 return 0;
605 }
606 return 1;
607}
c774aab9 608
7d76fdc8
MH
609/*
610 * current_ref is a performance hack: when iterating over references
611 * using the for_each_ref*() functions, current_ref is set to the
612 * current reference's entry before calling the callback function. If
613 * the callback function calls peel_ref(), then peel_ref() first
614 * checks whether the reference to be peeled is the current reference
615 * (it usually is) and if so, returns that reference's peeled version
616 * if it is available. This avoids a refname lookup in a common case.
617 */
bc5fd6d3 618static struct ref_entry *current_ref;
c774aab9 619
624cac35
MH
620typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data);
621
622struct ref_entry_cb {
623 const char *base;
624 int trim;
625 int flags;
626 each_ref_fn *fn;
627 void *cb_data;
628};
629
fcce1703 630/*
624cac35
MH
631 * Handle one reference in a do_for_each_ref*()-style iteration,
632 * calling an each_ref_fn for each entry.
fcce1703 633 */
624cac35 634static int do_one_ref(struct ref_entry *entry, void *cb_data)
bc5fd6d3 635{
624cac35 636 struct ref_entry_cb *data = cb_data;
429213e4 637 int retval;
624cac35 638 if (prefixcmp(entry->name, data->base))
bc5fd6d3 639 return 0;
c774aab9 640
624cac35 641 if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
662428f4 642 !ref_resolves_to_object(entry))
bc5fd6d3 643 return 0;
c774aab9 644
bc5fd6d3 645 current_ref = entry;
624cac35
MH
646 retval = data->fn(entry->name + data->trim, entry->u.value.sha1,
647 entry->flag, data->cb_data);
429213e4
MH
648 current_ref = NULL;
649 return retval;
bc5fd6d3 650}
c774aab9 651
c36b5bc2 652/*
d3177275 653 * Call fn for each reference in dir that has index in the range
432ad41e
MH
654 * offset <= index < dir->nr. Recurse into subdirectories that are in
655 * that index range, sorting them before iterating. This function
624cac35
MH
656 * does not sort dir itself; it should be sorted beforehand. fn is
657 * called for all references, including broken ones.
c36b5bc2 658 */
624cac35
MH
659static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset,
660 each_ref_entry_fn fn, void *cb_data)
c36b5bc2
MH
661{
662 int i;
d3177275
MH
663 assert(dir->sorted == dir->nr);
664 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
665 struct ref_entry *entry = dir->entries[i];
666 int retval;
667 if (entry->flag & REF_DIR) {
d7826d54
MH
668 struct ref_dir *subdir = get_ref_dir(entry);
669 sort_ref_dir(subdir);
624cac35 670 retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data);
432ad41e 671 } else {
624cac35 672 retval = fn(entry, cb_data);
432ad41e 673 }
c36b5bc2
MH
674 if (retval)
675 return retval;
676 }
677 return 0;
678}
679
b3fd060f 680/*
d3177275 681 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
682 * by refname. Recurse into subdirectories. If a value entry appears
683 * in both dir1 and dir2, then only process the version that is in
684 * dir2. The input dirs must already be sorted, but subdirs will be
624cac35
MH
685 * sorted as needed. fn is called for all references, including
686 * broken ones.
b3fd060f 687 */
624cac35
MH
688static int do_for_each_entry_in_dirs(struct ref_dir *dir1,
689 struct ref_dir *dir2,
690 each_ref_entry_fn fn, void *cb_data)
b3fd060f
MH
691{
692 int retval;
693 int i1 = 0, i2 = 0;
694
d3177275
MH
695 assert(dir1->sorted == dir1->nr);
696 assert(dir2->sorted == dir2->nr);
432ad41e
MH
697 while (1) {
698 struct ref_entry *e1, *e2;
699 int cmp;
700 if (i1 == dir1->nr) {
624cac35 701 return do_for_each_entry_in_dir(dir2, i2, fn, cb_data);
432ad41e
MH
702 }
703 if (i2 == dir2->nr) {
624cac35 704 return do_for_each_entry_in_dir(dir1, i1, fn, cb_data);
432ad41e
MH
705 }
706 e1 = dir1->entries[i1];
707 e2 = dir2->entries[i2];
708 cmp = strcmp(e1->name, e2->name);
709 if (cmp == 0) {
710 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
711 /* Both are directories; descend them in parallel. */
d7826d54
MH
712 struct ref_dir *subdir1 = get_ref_dir(e1);
713 struct ref_dir *subdir2 = get_ref_dir(e2);
714 sort_ref_dir(subdir1);
715 sort_ref_dir(subdir2);
624cac35
MH
716 retval = do_for_each_entry_in_dirs(
717 subdir1, subdir2, fn, cb_data);
432ad41e
MH
718 i1++;
719 i2++;
720 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
721 /* Both are references; ignore the one from dir1. */
624cac35 722 retval = fn(e2, cb_data);
432ad41e
MH
723 i1++;
724 i2++;
725 } else {
726 die("conflict between reference and directory: %s",
727 e1->name);
728 }
b3fd060f 729 } else {
432ad41e
MH
730 struct ref_entry *e;
731 if (cmp < 0) {
732 e = e1;
b3fd060f 733 i1++;
432ad41e
MH
734 } else {
735 e = e2;
736 i2++;
737 }
738 if (e->flag & REF_DIR) {
d7826d54
MH
739 struct ref_dir *subdir = get_ref_dir(e);
740 sort_ref_dir(subdir);
624cac35
MH
741 retval = do_for_each_entry_in_dir(
742 subdir, 0, fn, cb_data);
432ad41e 743 } else {
624cac35 744 retval = fn(e, cb_data);
b3fd060f
MH
745 }
746 }
747 if (retval)
748 return retval;
749 }
b3fd060f
MH
750}
751
98eeb09e
JK
752/*
753 * Load all of the refs from the dir into our in-memory cache. The hard work
754 * of loading loose refs is done by get_ref_dir(), so we just need to recurse
755 * through all of the sub-directories. We do not even need to care about
756 * sorting, as traversal order does not matter to us.
757 */
758static void prime_ref_dir(struct ref_dir *dir)
759{
760 int i;
761 for (i = 0; i < dir->nr; i++) {
762 struct ref_entry *entry = dir->entries[i];
763 if (entry->flag & REF_DIR)
764 prime_ref_dir(get_ref_dir(entry));
765 }
766}
d66da478
MH
767/*
768 * Return true iff refname1 and refname2 conflict with each other.
769 * Two reference names conflict if one of them exactly matches the
770 * leading components of the other; e.g., "foo/bar" conflicts with
771 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
772 * "foo/barbados".
773 */
774static int names_conflict(const char *refname1, const char *refname2)
775{
5a4d4947
MH
776 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
777 ;
778 return (*refname1 == '\0' && *refname2 == '/')
779 || (*refname1 == '/' && *refname2 == '\0');
780}
781
782struct name_conflict_cb {
783 const char *refname;
784 const char *oldrefname;
785 const char *conflicting_refname;
786};
787
624cac35 788static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
5a4d4947
MH
789{
790 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
624cac35 791 if (data->oldrefname && !strcmp(data->oldrefname, entry->name))
5a4d4947 792 return 0;
624cac35
MH
793 if (names_conflict(data->refname, entry->name)) {
794 data->conflicting_refname = entry->name;
5a4d4947 795 return 1;
d66da478 796 }
5a4d4947 797 return 0;
d66da478
MH
798}
799
bc5fd6d3
MH
800/*
801 * Return true iff a reference named refname could be created without
624cac35 802 * conflicting with the name of an existing reference in dir. If
5a4d4947
MH
803 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
804 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
805 * operation).
806 */
807static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 808 struct ref_dir *dir)
bc5fd6d3 809{
5a4d4947
MH
810 struct name_conflict_cb data;
811 data.refname = refname;
812 data.oldrefname = oldrefname;
813 data.conflicting_refname = NULL;
814
d3177275 815 sort_ref_dir(dir);
624cac35 816 if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) {
5a4d4947
MH
817 error("'%s' exists; cannot create '%s'",
818 data.conflicting_refname, refname);
819 return 0;
bc5fd6d3
MH
820 }
821 return 1;
e1e22e37
LT
822}
823
2fff7812
MH
824struct packed_ref_cache {
825 struct ref_entry *root;
9f69d297 826
5f5e2a88
MH
827 /*
828 * Count of references to the data structure in this instance,
829 * including the pointer from ref_cache::packed if any. The
830 * data will not be freed as long as the reference count is
831 * nonzero.
832 */
833 unsigned int referrers;
834
9f69d297
MH
835 /*
836 * Iff the packed-refs file associated with this instance is
837 * currently locked for writing, this points at the associated
4f6b83e3
MH
838 * lock (which is owned by somebody else). The referrer count
839 * is also incremented when the file is locked and decremented
840 * when it is unlocked.
9f69d297
MH
841 */
842 struct lock_file *lock;
ca919930
JK
843
844 /* The metadata from when this packed-refs cache was read */
845 struct stat_validity validity;
2fff7812
MH
846};
847
5e290ff7
JH
848/*
849 * Future: need to be in "struct repository"
850 * when doing a full libification.
851 */
79c7ca54
MH
852static struct ref_cache {
853 struct ref_cache *next;
d12229f5 854 struct ref_entry *loose;
2fff7812 855 struct packed_ref_cache *packed;
9da31cb0
MH
856 /*
857 * The submodule name, or "" for the main repo. We allocate
858 * length 1 rather than FLEX_ARRAY so that the main ref_cache
859 * is initialized correctly.
860 */
861 char name[1];
862} ref_cache, *submodule_ref_caches;
0e88c130 863
9f69d297
MH
864/* Lock used for the main packed-refs file: */
865static struct lock_file packlock;
866
5f5e2a88
MH
867/*
868 * Increment the reference count of *packed_refs.
869 */
870static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs)
871{
872 packed_refs->referrers++;
873}
874
875/*
876 * Decrease the reference count of *packed_refs. If it goes to zero,
877 * free *packed_refs and return true; otherwise return false.
878 */
879static int release_packed_ref_cache(struct packed_ref_cache *packed_refs)
880{
881 if (!--packed_refs->referrers) {
882 free_ref_entry(packed_refs->root);
ca919930 883 stat_validity_clear(&packed_refs->validity);
5f5e2a88
MH
884 free(packed_refs);
885 return 1;
886 } else {
887 return 0;
888 }
889}
890
760c4512 891static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 892{
d12229f5 893 if (refs->packed) {
5f5e2a88
MH
894 struct packed_ref_cache *packed_refs = refs->packed;
895
896 if (packed_refs->lock)
9f69d297 897 die("internal error: packed-ref cache cleared while locked");
d12229f5 898 refs->packed = NULL;
5f5e2a88 899 release_packed_ref_cache(packed_refs);
d12229f5 900 }
5e290ff7 901}
e1e22e37 902
760c4512
MH
903static void clear_loose_ref_cache(struct ref_cache *refs)
904{
d12229f5
MH
905 if (refs->loose) {
906 free_ref_entry(refs->loose);
907 refs->loose = NULL;
908 }
760c4512
MH
909}
910
79c7ca54 911static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 912{
ce40979c 913 int len;
79c7ca54 914 struct ref_cache *refs;
ce40979c
MH
915 if (!submodule)
916 submodule = "";
917 len = strlen(submodule) + 1;
79c7ca54 918 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 919 memcpy(refs->name, submodule, len);
e5dbf605
MH
920 return refs;
921}
922
4349a668 923/*
79c7ca54 924 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
925 * the main repository, use submodule==NULL. The returned structure
926 * will be allocated and initialized but not necessarily populated; it
927 * should not be freed.
928 */
79c7ca54 929static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 930{
9da31cb0
MH
931 struct ref_cache *refs;
932
933 if (!submodule || !*submodule)
934 return &ref_cache;
935
936 for (refs = submodule_ref_caches; refs; refs = refs->next)
0e88c130
MH
937 if (!strcmp(submodule, refs->name))
938 return refs;
0e88c130 939
79c7ca54 940 refs = create_ref_cache(submodule);
9da31cb0
MH
941 refs->next = submodule_ref_caches;
942 submodule_ref_caches = refs;
0e88c130 943 return refs;
4349a668
MH
944}
945
8be8bde7 946void invalidate_ref_cache(const char *submodule)
f130b116 947{
c5f29abd
MH
948 struct ref_cache *refs = get_ref_cache(submodule);
949 clear_packed_ref_cache(refs);
950 clear_loose_ref_cache(refs);
5e290ff7 951}
e1e22e37 952
3feb4f0c
MH
953/* The length of a peeled reference line in packed-refs, including EOL: */
954#define PEELED_LINE_LENGTH 42
955
694b7a19
MH
956/*
957 * The packed-refs header line that we write out. Perhaps other
958 * traits will be added later. The trailing space is required.
959 */
960static const char PACKED_REFS_HEADER[] =
961 "# pack-refs with: peeled fully-peeled \n";
962
bc5fd6d3
MH
963/*
964 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
965 * Return a pointer to the refname within the line (null-terminated),
966 * or NULL if there was a problem.
967 */
968static const char *parse_ref_line(char *line, unsigned char *sha1)
969{
970 /*
971 * 42: the answer to everything.
972 *
973 * In this case, it happens to be the answer to
974 * 40 (length of sha1 hex representation)
975 * +1 (space in between hex and name)
976 * +1 (newline at the end of the line)
977 */
978 int len = strlen(line) - 42;
979
980 if (len <= 0)
981 return NULL;
982 if (get_sha1_hex(line, sha1) < 0)
983 return NULL;
984 if (!isspace(line[40]))
985 return NULL;
986 line += 41;
987 if (isspace(*line))
988 return NULL;
989 if (line[len] != '\n')
990 return NULL;
991 line[len] = 0;
992
993 return line;
994}
995
c29c46fa
MH
996/*
997 * Read f, which is a packed-refs file, into dir.
998 *
999 * A comment line of the form "# pack-refs with: " may contain zero or
1000 * more traits. We interpret the traits as follows:
1001 *
1002 * No traits:
1003 *
1004 * Probably no references are peeled. But if the file contains a
1005 * peeled value for a reference, we will use it.
1006 *
1007 * peeled:
1008 *
1009 * References under "refs/tags/", if they *can* be peeled, *are*
1010 * peeled in this file. References outside of "refs/tags/" are
1011 * probably not peeled even if they could have been, but if we find
1012 * a peeled value for such a reference we will use it.
1013 *
1014 * fully-peeled:
1015 *
1016 * All references in the file that can be peeled are peeled.
1017 * Inversely (and this is more important), any references in the
1018 * file for which no peeled value is recorded is not peelable. This
1019 * trait should typically be written alongside "peeled" for
1020 * compatibility with older clients, but we do not require it
1021 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
1022 */
d3177275 1023static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 1024{
e9c4c111 1025 struct ref_entry *last = NULL;
f4204ab9 1026 char refline[PATH_MAX];
c29c46fa 1027 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
f4204ab9
JH
1028
1029 while (fgets(refline, sizeof(refline), f)) {
1030 unsigned char sha1[20];
dfefa935 1031 const char *refname;
f4204ab9
JH
1032 static const char header[] = "# pack-refs with:";
1033
1034 if (!strncmp(refline, header, sizeof(header)-1)) {
1035 const char *traits = refline + sizeof(header) - 1;
c29c46fa
MH
1036 if (strstr(traits, " fully-peeled "))
1037 peeled = PEELED_FULLY;
1038 else if (strstr(traits, " peeled "))
1039 peeled = PEELED_TAGS;
f4204ab9
JH
1040 /* perhaps other traits later as well */
1041 continue;
1042 }
1043
dfefa935
MH
1044 refname = parse_ref_line(refline, sha1);
1045 if (refname) {
c29c46fa
MH
1046 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
1047 if (peeled == PEELED_FULLY ||
1048 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
1049 last->flag |= REF_KNOWS_PEELED;
d3177275 1050 add_ref(dir, last);
f4204ab9
JH
1051 continue;
1052 }
1053 if (last &&
1054 refline[0] == '^' &&
3feb4f0c
MH
1055 strlen(refline) == PEELED_LINE_LENGTH &&
1056 refline[PEELED_LINE_LENGTH - 1] == '\n' &&
c29c46fa 1057 !get_sha1_hex(refline + 1, sha1)) {
593f1bb8 1058 hashcpy(last->u.value.peeled, sha1);
c29c46fa
MH
1059 /*
1060 * Regardless of what the file header said,
1061 * we definitely know the value of *this*
1062 * reference:
1063 */
1064 last->flag |= REF_KNOWS_PEELED;
1065 }
f4204ab9 1066 }
f4204ab9
JH
1067}
1068
2fff7812
MH
1069/*
1070 * Get the packed_ref_cache for the specified ref_cache, creating it
1071 * if necessary.
1072 */
1073static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)
5e290ff7 1074{
ca919930
JK
1075 const char *packed_refs_file;
1076
1077 if (*refs->name)
1078 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
1079 else
1080 packed_refs_file = git_path("packed-refs");
1081
1082 if (refs->packed &&
1083 !stat_validity_check(&refs->packed->validity, packed_refs_file))
1084 clear_packed_ref_cache(refs);
1085
d12229f5 1086 if (!refs->packed) {
4349a668 1087 FILE *f;
0bad611b 1088
2fff7812 1089 refs->packed = xcalloc(1, sizeof(*refs->packed));
5f5e2a88 1090 acquire_packed_ref_cache(refs->packed);
2fff7812 1091 refs->packed->root = create_dir_entry(refs, "", 0, 0);
4349a668 1092 f = fopen(packed_refs_file, "r");
e1e22e37 1093 if (f) {
ca919930 1094 stat_validity_update(&refs->packed->validity, fileno(f));
2fff7812 1095 read_packed_refs(f, get_ref_dir(refs->packed->root));
e1e22e37 1096 fclose(f);
e1e22e37 1097 }
e1e22e37 1098 }
2fff7812
MH
1099 return refs->packed;
1100}
1101
1102static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)
1103{
1104 return get_ref_dir(packed_ref_cache->root);
1105}
1106
1107static struct ref_dir *get_packed_refs(struct ref_cache *refs)
1108{
1109 return get_packed_ref_dir(get_packed_ref_cache(refs));
e1e22e37
LT
1110}
1111
30249ee6
MH
1112void add_packed_ref(const char *refname, const unsigned char *sha1)
1113{
9f69d297
MH
1114 struct packed_ref_cache *packed_ref_cache =
1115 get_packed_ref_cache(&ref_cache);
1116
1117 if (!packed_ref_cache->lock)
1118 die("internal error: packed refs not locked");
1119 add_ref(get_packed_ref_dir(packed_ref_cache),
9da31cb0 1120 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
30249ee6
MH
1121}
1122
abc39098 1123/*
28e6a34e
MH
1124 * Read the loose references from the namespace dirname into dir
1125 * (without recursing). dirname must end with '/'. dir must be the
1126 * directory entry corresponding to dirname.
abc39098 1127 */
423a1afc 1128static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 1129{
423a1afc 1130 struct ref_cache *refs = dir->ref_cache;
d3177275 1131 DIR *d;
0bad611b 1132 const char *path;
d5fdae67 1133 struct dirent *de;
abc39098 1134 int dirnamelen = strlen(dirname);
72b64b44 1135 struct strbuf refname;
0bad611b 1136
3b124823 1137 if (*refs->name)
66a3d20b 1138 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 1139 else
66a3d20b 1140 path = git_path("%s", dirname);
0bad611b 1141
d3177275 1142 d = opendir(path);
d5fdae67
MH
1143 if (!d)
1144 return;
1145
66a3d20b
MH
1146 strbuf_init(&refname, dirnamelen + 257);
1147 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
1148
1149 while ((de = readdir(d)) != NULL) {
1150 unsigned char sha1[20];
1151 struct stat st;
1152 int flag;
d5fdae67
MH
1153 const char *refdir;
1154
1155 if (de->d_name[0] == '.')
1156 continue;
d5fdae67
MH
1157 if (has_extension(de->d_name, ".lock"))
1158 continue;
72b64b44 1159 strbuf_addstr(&refname, de->d_name);
d5fdae67 1160 refdir = *refs->name
72b64b44
MH
1161 ? git_path_submodule(refs->name, "%s", refname.buf)
1162 : git_path("%s", refname.buf);
1163 if (stat(refdir, &st) < 0) {
1164 ; /* silently ignore */
1165 } else if (S_ISDIR(st.st_mode)) {
abc39098 1166 strbuf_addch(&refname, '/');
28e6a34e 1167 add_entry_to_dir(dir,
b9146f51
RS
1168 create_dir_entry(refs, refname.buf,
1169 refname.len, 1));
72b64b44 1170 } else {
3b124823 1171 if (*refs->name) {
f8948e2f 1172 hashclr(sha1);
0bad611b 1173 flag = 0;
72b64b44 1174 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
0bad611b 1175 hashclr(sha1);
98ac34b2 1176 flag |= REF_ISBROKEN;
0bad611b 1177 }
72b64b44 1178 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
1179 hashclr(sha1);
1180 flag |= REF_ISBROKEN;
1181 }
9f2fb4a3
MH
1182 add_entry_to_dir(dir,
1183 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 1184 }
66a3d20b 1185 strbuf_setlen(&refname, dirnamelen);
e1e22e37 1186 }
72b64b44 1187 strbuf_release(&refname);
d5fdae67 1188 closedir(d);
e1e22e37
LT
1189}
1190
d3177275 1191static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 1192{
d12229f5 1193 if (!refs->loose) {
28e6a34e
MH
1194 /*
1195 * Mark the top-level directory complete because we
1196 * are about to read the only subdirectory that can
1197 * hold references:
1198 */
b9146f51 1199 refs->loose = create_dir_entry(refs, "", 0, 0);
28e6a34e
MH
1200 /*
1201 * Create an incomplete entry for "refs/":
1202 */
1203 add_entry_to_dir(get_ref_dir(refs->loose),
b9146f51 1204 create_dir_entry(refs, "refs/", 5, 1));
e1e22e37 1205 }
d7826d54 1206 return get_ref_dir(refs->loose);
e1e22e37
LT
1207}
1208
ca8db142
LT
1209/* We allow "recursive" symbolic refs. Only within reason, though */
1210#define MAXDEPTH 5
0ebde32c
LT
1211#define MAXREFLEN (1024)
1212
e5fa45c1
JH
1213/*
1214 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
1215 * from the loose refs in ref_cache refs. Find <refname> in the
1216 * packed-refs file for the submodule.
e5fa45c1 1217 */
b0626608 1218static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 1219 const char *refname, unsigned char *sha1)
0ebde32c 1220{
2c5c66be 1221 struct ref_entry *ref;
d3177275 1222 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 1223
432ad41e 1224 ref = find_ref(dir, refname);
b0626608
MH
1225 if (ref == NULL)
1226 return -1;
1227
593f1bb8 1228 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 1229 return 0;
0ebde32c
LT
1230}
1231
b0626608 1232static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 1233 const char *refname, unsigned char *sha1,
dfefa935 1234 int recursion)
0ebde32c 1235{
064d51dc 1236 int fd, len;
0ebde32c 1237 char buffer[128], *p;
064d51dc 1238 char *path;
0ebde32c 1239
064d51dc 1240 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 1241 return -1;
064d51dc
MH
1242 path = *refs->name
1243 ? git_path_submodule(refs->name, "%s", refname)
1244 : git_path("%s", refname);
1245 fd = open(path, O_RDONLY);
0ebde32c 1246 if (fd < 0)
b0626608 1247 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
1248
1249 len = read(fd, buffer, sizeof(buffer)-1);
1250 close(fd);
1251 if (len < 0)
1252 return -1;
1253 while (len && isspace(buffer[len-1]))
1254 len--;
1255 buffer[len] = 0;
1256
1257 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 1258 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
1259 return 0;
1260
1261 /* Symref? */
1262 if (strncmp(buffer, "ref:", 4))
1263 return -1;
1264 p = buffer + 4;
1265 while (isspace(*p))
1266 p++;
1267
064d51dc 1268 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
1269}
1270
85be1fe3 1271int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
1272{
1273 int len = strlen(path), retval;
064d51dc 1274 char *submodule;
b0626608 1275 struct ref_cache *refs;
0ebde32c
LT
1276
1277 while (len && path[len-1] == '/')
1278 len--;
1279 if (!len)
1280 return -1;
b0626608
MH
1281 submodule = xstrndup(path, len);
1282 refs = get_ref_cache(submodule);
1283 free(submodule);
1284
064d51dc 1285 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
1286 return retval;
1287}
ca8db142 1288
4886b89f 1289/*
63331581
MH
1290 * Return the ref_entry for the given refname from the packed
1291 * references. If it does not exist, return NULL.
4886b89f 1292 */
63331581 1293static struct ref_entry *get_packed_ref(const char *refname)
c224ca7f 1294{
9da31cb0 1295 return find_ref(get_packed_refs(&ref_cache), refname);
c224ca7f
MH
1296}
1297
8d68493f 1298const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 1299{
0104ca09
HO
1300 int depth = MAXDEPTH;
1301 ssize_t len;
a876ed83 1302 char buffer[256];
dfefa935 1303 static char refname_buffer[256];
ca8db142 1304
8da19775
JH
1305 if (flag)
1306 *flag = 0;
1307
dfefa935 1308 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
1309 return NULL;
1310
a876ed83 1311 for (;;) {
55956350 1312 char path[PATH_MAX];
a876ed83
JH
1313 struct stat st;
1314 char *buf;
1315 int fd;
8a65ff76 1316
a876ed83
JH
1317 if (--depth < 0)
1318 return NULL;
ca8db142 1319
dfefa935 1320 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 1321
a876ed83 1322 if (lstat(path, &st) < 0) {
63331581
MH
1323 struct ref_entry *entry;
1324
c224ca7f
MH
1325 if (errno != ENOENT)
1326 return NULL;
1327 /*
1328 * The loose reference file does not exist;
1329 * check for a packed reference.
1330 */
63331581
MH
1331 entry = get_packed_ref(refname);
1332 if (entry) {
1333 hashcpy(sha1, entry->u.value.sha1);
c224ca7f
MH
1334 if (flag)
1335 *flag |= REF_ISPACKED;
dfefa935 1336 return refname;
434cd0cd 1337 }
c224ca7f
MH
1338 /* The reference is not a packed reference, either. */
1339 if (reading) {
a876ed83 1340 return NULL;
c224ca7f
MH
1341 } else {
1342 hashclr(sha1);
dfefa935 1343 return refname;
c224ca7f 1344 }
a876ed83 1345 }
ca8db142 1346
a876ed83
JH
1347 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1348 if (S_ISLNK(st.st_mode)) {
1349 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
1350 if (len < 0)
1351 return NULL;
b54cb795 1352 buffer[len] = 0;
1f58a038
MH
1353 if (!prefixcmp(buffer, "refs/") &&
1354 !check_refname_format(buffer, 0)) {
dfefa935
MH
1355 strcpy(refname_buffer, buffer);
1356 refname = refname_buffer;
8da19775
JH
1357 if (flag)
1358 *flag |= REF_ISSYMREF;
a876ed83
JH
1359 continue;
1360 }
ca8db142 1361 }
a876ed83 1362
7a21632f
DS
1363 /* Is it a directory? */
1364 if (S_ISDIR(st.st_mode)) {
1365 errno = EISDIR;
1366 return NULL;
1367 }
1368
a876ed83
JH
1369 /*
1370 * Anything else, just open it and try to use it as
1371 * a ref
1372 */
1373 fd = open(path, O_RDONLY);
1374 if (fd < 0)
1375 return NULL;
93d26e4c 1376 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1377 close(fd);
28775050
MH
1378 if (len < 0)
1379 return NULL;
1380 while (len && isspace(buffer[len-1]))
1381 len--;
1382 buffer[len] = '\0';
a876ed83
JH
1383
1384 /*
1385 * Is it a symbolic ref?
1386 */
28775050 1387 if (prefixcmp(buffer, "ref:"))
a876ed83 1388 break;
55956350
JH
1389 if (flag)
1390 *flag |= REF_ISSYMREF;
a876ed83 1391 buf = buffer + 4;
28775050
MH
1392 while (isspace(*buf))
1393 buf++;
313fb010 1394 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1395 if (flag)
1396 *flag |= REF_ISBROKEN;
313fb010
MH
1397 return NULL;
1398 }
dfefa935 1399 refname = strcpy(refname_buffer, buf);
8a65ff76 1400 }
f989fea0
MH
1401 /* Please note that FETCH_HEAD has a second line containing other data. */
1402 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1403 if (flag)
1404 *flag |= REF_ISBROKEN;
a876ed83 1405 return NULL;
629cd3ac 1406 }
dfefa935 1407 return refname;
a876ed83
JH
1408}
1409
96ec7b1e
NTND
1410char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1411{
8cad4744 1412 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1413 return ret ? xstrdup(ret) : NULL;
1414}
1415
d08bae7e
IL
1416/* The argument to filter_refs */
1417struct ref_filter {
1418 const char *pattern;
1419 each_ref_fn *fn;
1420 void *cb_data;
1421};
1422
dfefa935 1423int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1424{
8d68493f 1425 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1426 return 0;
1427 return -1;
8a65ff76
LT
1428}
1429
dfefa935 1430int read_ref(const char *refname, unsigned char *sha1)
c6893323 1431{
dfefa935 1432 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1433}
1434
bc5fd6d3 1435int ref_exists(const char *refname)
ef06b918 1436{
bc5fd6d3
MH
1437 unsigned char sha1[20];
1438 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1439}
1440
85be1fe3 1441static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1442 void *data)
d08bae7e
IL
1443{
1444 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1445 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1446 return 0;
85be1fe3 1447 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1448}
1449
68cf8703
MH
1450enum peel_status {
1451 /* object was peeled successfully: */
1452 PEEL_PEELED = 0,
1453
1454 /*
1455 * object cannot be peeled because the named object (or an
1456 * object referred to by a tag in the peel chain), does not
1457 * exist.
1458 */
1459 PEEL_INVALID = -1,
1460
1461 /* object cannot be peeled because it is not a tag: */
9a489f3c
MH
1462 PEEL_NON_TAG = -2,
1463
1464 /* ref_entry contains no peeled value because it is a symref: */
1465 PEEL_IS_SYMREF = -3,
1466
1467 /*
1468 * ref_entry cannot be peeled because it is broken (i.e., the
1469 * symbolic reference cannot even be resolved to an object
1470 * name):
1471 */
1472 PEEL_BROKEN = -4
68cf8703
MH
1473};
1474
cb2ae1c4
MH
1475/*
1476 * Peel the named object; i.e., if the object is a tag, resolve the
68cf8703
MH
1477 * tag recursively until a non-tag is found. If successful, store the
1478 * result to sha1 and return PEEL_PEELED. If the object is not a tag
1479 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
1480 * and leave sha1 unchanged.
cb2ae1c4 1481 */
68cf8703 1482static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
cb2ae1c4
MH
1483{
1484 struct object *o = lookup_unknown_object(name);
1485
1486 if (o->type == OBJ_NONE) {
1487 int type = sha1_object_info(name, NULL);
1488 if (type < 0)
68cf8703 1489 return PEEL_INVALID;
cb2ae1c4
MH
1490 o->type = type;
1491 }
1492
1493 if (o->type != OBJ_TAG)
68cf8703 1494 return PEEL_NON_TAG;
cb2ae1c4
MH
1495
1496 o = deref_tag_noverify(o);
1497 if (!o)
68cf8703 1498 return PEEL_INVALID;
cb2ae1c4
MH
1499
1500 hashcpy(sha1, o->sha1);
68cf8703 1501 return PEEL_PEELED;
cb2ae1c4
MH
1502}
1503
9a489f3c 1504/*
f85354b5
MH
1505 * Peel the entry (if possible) and return its new peel_status. If
1506 * repeel is true, re-peel the entry even if there is an old peeled
1507 * value that is already stored in it.
694b7a19
MH
1508 *
1509 * It is OK to call this function with a packed reference entry that
1510 * might be stale and might even refer to an object that has since
1511 * been garbage-collected. In such a case, if the entry has
1512 * REF_KNOWS_PEELED then leave the status unchanged and return
1513 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.
9a489f3c 1514 */
f85354b5 1515static enum peel_status peel_entry(struct ref_entry *entry, int repeel)
9a489f3c
MH
1516{
1517 enum peel_status status;
1518
f85354b5
MH
1519 if (entry->flag & REF_KNOWS_PEELED) {
1520 if (repeel) {
1521 entry->flag &= ~REF_KNOWS_PEELED;
1522 hashclr(entry->u.value.peeled);
1523 } else {
1524 return is_null_sha1(entry->u.value.peeled) ?
1525 PEEL_NON_TAG : PEEL_PEELED;
1526 }
1527 }
9a489f3c
MH
1528 if (entry->flag & REF_ISBROKEN)
1529 return PEEL_BROKEN;
1530 if (entry->flag & REF_ISSYMREF)
1531 return PEEL_IS_SYMREF;
1532
1533 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);
1534 if (status == PEEL_PEELED || status == PEEL_NON_TAG)
1535 entry->flag |= REF_KNOWS_PEELED;
1536 return status;
1537}
1538
dfefa935 1539int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1540{
1541 int flag;
1542 unsigned char base[20];
cf0adba7 1543
dfefa935 1544 if (current_ref && (current_ref->name == refname
9a489f3c 1545 || !strcmp(current_ref->name, refname))) {
f85354b5 1546 if (peel_entry(current_ref, 0))
9a489f3c
MH
1547 return -1;
1548 hashcpy(sha1, current_ref->u.value.peeled);
1549 return 0;
0ae91be0
SP
1550 }
1551
dfefa935 1552 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1553 return -1;
1554
9a489f3c
MH
1555 /*
1556 * If the reference is packed, read its ref_entry from the
1557 * cache in the hope that we already know its peeled value.
1558 * We only try this optimization on packed references because
1559 * (a) forcing the filling of the loose reference cache could
1560 * be expensive and (b) loose references anyway usually do not
1561 * have REF_KNOWS_PEELED.
1562 */
1563 if (flag & REF_ISPACKED) {
f361baeb 1564 struct ref_entry *r = get_packed_ref(refname);
9a489f3c 1565 if (r) {
f85354b5 1566 if (peel_entry(r, 0))
9a489f3c 1567 return -1;
593f1bb8 1568 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1569 return 0;
cf0adba7 1570 }
cf0adba7
JH
1571 }
1572
cb2ae1c4 1573 return peel_object(base, sha1);
cf0adba7
JH
1574}
1575
bc5fd6d3
MH
1576struct warn_if_dangling_data {
1577 FILE *fp;
1578 const char *refname;
1579 const char *msg_fmt;
1580};
1581
1582static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1583 int flags, void *cb_data)
1584{
1585 struct warn_if_dangling_data *d = cb_data;
1586 const char *resolves_to;
1587 unsigned char junk[20];
1588
1589 if (!(flags & REF_ISSYMREF))
1590 return 0;
1591
1592 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1593 if (!resolves_to || strcmp(resolves_to, d->refname))
1594 return 0;
1595
1596 fprintf(d->fp, d->msg_fmt, refname);
1be65eda 1597 fputc('\n', d->fp);
bc5fd6d3
MH
1598 return 0;
1599}
1600
1601void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1602{
1603 struct warn_if_dangling_data data;
1604
1605 data.fp = fp;
1606 data.refname = refname;
1607 data.msg_fmt = msg_fmt;
1608 for_each_rawref(warn_if_dangling_symref, &data);
1609}
1610
fcce1703 1611/*
65cf102b 1612 * Call fn for each reference in the specified ref_cache, omitting
624cac35
MH
1613 * references not in the containing_dir of base. fn is called for all
1614 * references, including broken ones. If fn ever returns a non-zero
fcce1703
MH
1615 * value, stop the iteration and return that value; otherwise, return
1616 * 0.
1617 */
65cf102b 1618static int do_for_each_entry(struct ref_cache *refs, const char *base,
624cac35 1619 each_ref_entry_fn fn, void *cb_data)
8a65ff76 1620{
98eeb09e
JK
1621 struct packed_ref_cache *packed_ref_cache;
1622 struct ref_dir *loose_dir;
1623 struct ref_dir *packed_dir;
933ac036
MH
1624 int retval = 0;
1625
98eeb09e
JK
1626 /*
1627 * We must make sure that all loose refs are read before accessing the
1628 * packed-refs file; this avoids a race condition in which loose refs
1629 * are migrated to the packed-refs file by a simultaneous process, but
1630 * our in-memory view is from before the migration. get_packed_ref_cache()
1631 * takes care of making sure our view is up to date with what is on
1632 * disk.
1633 */
1634 loose_dir = get_loose_refs(refs);
1635 if (base && *base) {
1636 loose_dir = find_containing_dir(loose_dir, base, 0);
1637 }
1638 if (loose_dir)
1639 prime_ref_dir(loose_dir);
1640
1641 packed_ref_cache = get_packed_ref_cache(refs);
8baf2bb9 1642 acquire_packed_ref_cache(packed_ref_cache);
98eeb09e 1643 packed_dir = get_packed_ref_dir(packed_ref_cache);
933ac036
MH
1644 if (base && *base) {
1645 packed_dir = find_containing_dir(packed_dir, base, 0);
933ac036
MH
1646 }
1647
1648 if (packed_dir && loose_dir) {
1649 sort_ref_dir(packed_dir);
1650 sort_ref_dir(loose_dir);
624cac35
MH
1651 retval = do_for_each_entry_in_dirs(
1652 packed_dir, loose_dir, fn, cb_data);
933ac036
MH
1653 } else if (packed_dir) {
1654 sort_ref_dir(packed_dir);
624cac35
MH
1655 retval = do_for_each_entry_in_dir(
1656 packed_dir, 0, fn, cb_data);
933ac036
MH
1657 } else if (loose_dir) {
1658 sort_ref_dir(loose_dir);
624cac35
MH
1659 retval = do_for_each_entry_in_dir(
1660 loose_dir, 0, fn, cb_data);
933ac036
MH
1661 }
1662
8baf2bb9 1663 release_packed_ref_cache(packed_ref_cache);
933ac036 1664 return retval;
8a65ff76
LT
1665}
1666
624cac35 1667/*
65cf102b 1668 * Call fn for each reference in the specified ref_cache for which the
624cac35
MH
1669 * refname begins with base. If trim is non-zero, then trim that many
1670 * characters off the beginning of each refname before passing the
1671 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include
1672 * broken references in the iteration. If fn ever returns a non-zero
1673 * value, stop the iteration and return that value; otherwise, return
1674 * 0.
1675 */
65cf102b
MH
1676static int do_for_each_ref(struct ref_cache *refs, const char *base,
1677 each_ref_fn fn, int trim, int flags, void *cb_data)
624cac35
MH
1678{
1679 struct ref_entry_cb data;
1680 data.base = base;
1681 data.trim = trim;
1682 data.flags = flags;
1683 data.fn = fn;
1684 data.cb_data = cb_data;
1685
65cf102b 1686 return do_for_each_entry(refs, base, do_one_ref, &data);
624cac35
MH
1687}
1688
0bad611b 1689static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1690{
1691 unsigned char sha1[20];
8da19775
JH
1692 int flag;
1693
0bad611b
HV
1694 if (submodule) {
1695 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1696 return fn("HEAD", sha1, 0, cb_data);
1697
1698 return 0;
1699 }
1700
c6893323 1701 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1702 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1703
2f34ba32 1704 return 0;
723c31fe
LT
1705}
1706
0bad611b
HV
1707int head_ref(each_ref_fn fn, void *cb_data)
1708{
1709 return do_head_ref(NULL, fn, cb_data);
1710}
1711
9ef6aeb0
HV
1712int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1713{
1714 return do_head_ref(submodule, fn, cb_data);
1715}
1716
cb5d709f 1717int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1718{
9da31cb0 1719 return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);
a62be77f
SE
1720}
1721
9ef6aeb0
HV
1722int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1723{
65cf102b 1724 return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data);
a62be77f
SE
1725}
1726
2a8177b6
CC
1727int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1728{
9da31cb0 1729 return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1730}
1731
9ef6aeb0
HV
1732int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1733 each_ref_fn fn, void *cb_data)
1734{
65cf102b 1735 return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1736}
1737
cb5d709f 1738int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1739{
2a8177b6 1740 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1741}
1742
9ef6aeb0
HV
1743int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1744{
1745 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1746}
1747
cb5d709f 1748int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1749{
2a8177b6 1750 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1751}
1752
9ef6aeb0
HV
1753int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1754{
1755 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1756}
1757
cb5d709f 1758int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1759{
2a8177b6 1760 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1761}
1762
9ef6aeb0
HV
1763int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1764{
1765 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1766}
1767
29268700
CC
1768int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1769{
9da31cb0 1770 return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1771}
1772
a1bea2c1
JT
1773int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1774{
1775 struct strbuf buf = STRBUF_INIT;
1776 int ret = 0;
1777 unsigned char sha1[20];
1778 int flag;
1779
1780 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1781 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1782 ret = fn(buf.buf, sha1, flag, cb_data);
1783 strbuf_release(&buf);
1784
1785 return ret;
1786}
1787
1788int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1789{
1790 struct strbuf buf = STRBUF_INIT;
1791 int ret;
1792 strbuf_addf(&buf, "%srefs/", get_git_namespace());
9da31cb0 1793 ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);
a1bea2c1
JT
1794 strbuf_release(&buf);
1795 return ret;
1796}
1797
b09fe971
IL
1798int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1799 const char *prefix, void *cb_data)
d08bae7e
IL
1800{
1801 struct strbuf real_pattern = STRBUF_INIT;
1802 struct ref_filter filter;
d08bae7e
IL
1803 int ret;
1804
b09fe971 1805 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1806 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1807 else if (prefix)
1808 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1809 strbuf_addstr(&real_pattern, pattern);
1810
894a9d33 1811 if (!has_glob_specials(pattern)) {
9517e6b8 1812 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1813 if (real_pattern.buf[real_pattern.len - 1] != '/')
1814 strbuf_addch(&real_pattern, '/');
1815 /* No need to check for '*', there is none. */
1816 strbuf_addch(&real_pattern, '*');
1817 }
1818
1819 filter.pattern = real_pattern.buf;
1820 filter.fn = fn;
1821 filter.cb_data = cb_data;
1822 ret = for_each_ref(filter_refs, &filter);
1823
1824 strbuf_release(&real_pattern);
1825 return ret;
1826}
1827
b09fe971
IL
1828int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1829{
1830 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1831}
1832
f8948e2f
JH
1833int for_each_rawref(each_ref_fn fn, void *cb_data)
1834{
9da31cb0 1835 return do_for_each_ref(&ref_cache, "", fn, 0,
f8948e2f 1836 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1837}
1838
4577e483 1839const char *prettify_refname(const char *name)
a9c37a72 1840{
a9c37a72
DB
1841 return name + (
1842 !prefixcmp(name, "refs/heads/") ? 11 :
1843 !prefixcmp(name, "refs/tags/") ? 10 :
1844 !prefixcmp(name, "refs/remotes/") ? 13 :
1845 0);
1846}
1847
79803322
SP
1848const char *ref_rev_parse_rules[] = {
1849 "%.*s",
1850 "refs/%.*s",
1851 "refs/tags/%.*s",
1852 "refs/heads/%.*s",
1853 "refs/remotes/%.*s",
1854 "refs/remotes/%.*s/HEAD",
1855 NULL
1856};
1857
1858int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1859{
1860 const char **p;
1861 const int abbrev_name_len = strlen(abbrev_name);
1862
1863 for (p = rules; *p; p++) {
1864 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1865 return 1;
1866 }
1867 }
1868
1869 return 0;
1870}
1871
e5f38ec3 1872static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1873 const unsigned char *old_sha1, int mustexist)
1874{
c6893323 1875 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1876 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1877 unlock_ref(lock);
1878 return NULL;
1879 }
a89fccd2 1880 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1881 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1882 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1883 unlock_ref(lock);
1884 return NULL;
1885 }
1886 return lock;
1887}
1888
7155b727 1889static int remove_empty_directories(const char *file)
bc7127ef
JH
1890{
1891 /* we want to create a file but there is a directory there;
1892 * if that is an empty directory (or a directory that contains
1893 * only empty directories), remove them.
1894 */
7155b727
JS
1895 struct strbuf path;
1896 int result;
bc7127ef 1897
7155b727
JS
1898 strbuf_init(&path, 20);
1899 strbuf_addstr(&path, file);
1900
a0f4afbe 1901 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1902
1903 strbuf_release(&path);
1904
1905 return result;
bc7127ef
JH
1906}
1907
ff74f7f1
JH
1908/*
1909 * *string and *len will only be substituted, and *string returned (for
1910 * later free()ing) if the string passed in is a magic short-hand form
1911 * to name a branch.
1912 */
1913static char *substitute_branch_name(const char **string, int *len)
1914{
1915 struct strbuf buf = STRBUF_INIT;
1916 int ret = interpret_branch_name(*string, &buf);
1917
1918 if (ret == *len) {
1919 size_t size;
1920 *string = strbuf_detach(&buf, &size);
1921 *len = size;
1922 return (char *)*string;
1923 }
1924
1925 return NULL;
1926}
1927
1928int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1929{
1930 char *last_branch = substitute_branch_name(&str, &len);
1931 const char **p, *r;
1932 int refs_found = 0;
1933
1934 *ref = NULL;
1935 for (p = ref_rev_parse_rules; *p; p++) {
1936 char fullref[PATH_MAX];
1937 unsigned char sha1_from_ref[20];
1938 unsigned char *this_result;
1939 int flag;
1940
1941 this_result = refs_found ? sha1_from_ref : sha1;
1942 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1943 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1944 if (r) {
1945 if (!refs_found++)
1946 *ref = xstrdup(r);
1947 if (!warn_ambiguous_refs)
1948 break;
55956350 1949 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1950 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1951 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1952 warning("ignoring broken ref %s.", fullref);
1953 }
ff74f7f1
JH
1954 }
1955 free(last_branch);
1956 return refs_found;
1957}
1958
1959int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1960{
1961 char *last_branch = substitute_branch_name(&str, &len);
1962 const char **p;
1963 int logs_found = 0;
1964
1965 *log = NULL;
1966 for (p = ref_rev_parse_rules; *p; p++) {
1967 struct stat st;
1968 unsigned char hash[20];
1969 char path[PATH_MAX];
1970 const char *ref, *it;
1971
1972 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1973 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1974 if (!ref)
1975 continue;
1976 if (!stat(git_path("logs/%s", path), &st) &&
1977 S_ISREG(st.st_mode))
1978 it = path;
1979 else if (strcmp(ref, path) &&
1980 !stat(git_path("logs/%s", ref), &st) &&
1981 S_ISREG(st.st_mode))
1982 it = ref;
1983 else
1984 continue;
1985 if (!logs_found++) {
1986 *log = xstrdup(it);
1987 hashcpy(sha1, hash);
1988 }
1989 if (!warn_ambiguous_refs)
1990 break;
1991 }
1992 free(last_branch);
1993 return logs_found;
1994}
1995
dfefa935
MH
1996static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1997 const unsigned char *old_sha1,
1998 int flags, int *type_p)
4bd18c43 1999{
434cd0cd 2000 char *ref_file;
dfefa935 2001 const char *orig_refname = refname;
4bd18c43 2002 struct ref_lock *lock;
5cc3cef9 2003 int last_errno = 0;
acd3b9ec 2004 int type, lflags;
4431fcc4 2005 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 2006 int missing = 0;
4bd18c43
SP
2007
2008 lock = xcalloc(1, sizeof(struct ref_lock));
2009 lock->lock_fd = -1;
2010
8d68493f 2011 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 2012 if (!refname && errno == EISDIR) {
bc7127ef
JH
2013 /* we are trying to lock foo but we used to
2014 * have foo/bar which now does not exist;
2015 * it is normal for the empty directory 'foo'
2016 * to remain.
2017 */
dfefa935 2018 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
2019 if (remove_empty_directories(ref_file)) {
2020 last_errno = errno;
dfefa935 2021 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
2022 goto error_return;
2023 }
8d68493f 2024 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 2025 }
68db31cc
SV
2026 if (type_p)
2027 *type_p = type;
dfefa935 2028 if (!refname) {
5cc3cef9 2029 last_errno = errno;
818f477c 2030 error("unable to resolve reference %s: %s",
dfefa935 2031 orig_refname, strerror(errno));
5cc3cef9 2032 goto error_return;
4bd18c43 2033 }
5bdd8d4a 2034 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
2035 /* When the ref did not exist and we are creating it,
2036 * make sure there is no existing ref that is packed
2037 * whose name begins with our refname, nor a ref whose
2038 * name is a proper prefix of our refname.
2039 */
5bdd8d4a 2040 if (missing &&
9da31cb0 2041 !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {
f475e08e 2042 last_errno = ENOTDIR;
c976d415 2043 goto error_return;
f475e08e 2044 }
22a3844e 2045
c33d5174 2046 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 2047
acd3b9ec
JH
2048 lflags = LOCK_DIE_ON_ERROR;
2049 if (flags & REF_NODEREF) {
dfefa935 2050 refname = orig_refname;
acd3b9ec
JH
2051 lflags |= LOCK_NODEREF;
2052 }
dfefa935
MH
2053 lock->ref_name = xstrdup(refname);
2054 lock->orig_ref_name = xstrdup(orig_refname);
2055 ref_file = git_path("%s", refname);
5bdd8d4a 2056 if (missing)
68db31cc
SV
2057 lock->force_write = 1;
2058 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
2059 lock->force_write = 1;
4bd18c43 2060
5cc3cef9
JH
2061 if (safe_create_leading_directories(ref_file)) {
2062 last_errno = errno;
2063 error("unable to create directory for %s", ref_file);
2064 goto error_return;
2065 }
4bd18c43 2066
acd3b9ec 2067 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 2068 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
2069
2070 error_return:
2071 unlock_ref(lock);
2072 errno = last_errno;
2073 return NULL;
4bd18c43
SP
2074}
2075
dfefa935 2076struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 2077{
53cce84c 2078 char refpath[PATH_MAX];
dfefa935 2079 if (check_refname_format(refname, 0))
4bd18c43 2080 return NULL;
dfefa935 2081 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 2082 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
2083}
2084
dfefa935
MH
2085struct ref_lock *lock_any_ref_for_update(const char *refname,
2086 const unsigned char *old_sha1, int flags)
4bd18c43 2087{
dfefa935 2088 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 2089 return NULL;
dfefa935 2090 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
2091}
2092
fec3137f
MH
2093/*
2094 * Write an entry to the packed-refs file for the specified refname.
2095 * If peeled is non-NULL, write it as the entry's peeled value.
2096 */
2097static void write_packed_entry(int fd, char *refname, unsigned char *sha1,
2098 unsigned char *peeled)
d66da478 2099{
d66da478
MH
2100 char line[PATH_MAX + 100];
2101 int len;
2102
d66da478
MH
2103 len = snprintf(line, sizeof(line), "%s %s\n",
2104 sha1_to_hex(sha1), refname);
2105 /* this should not happen but just being defensive */
2106 if (len > sizeof(line))
2107 die("too long a refname '%s'", refname);
fec3137f
MH
2108 write_or_die(fd, line, len);
2109
2110 if (peeled) {
2111 if (snprintf(line, sizeof(line), "^%s\n",
2112 sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)
2113 die("internal error");
2114 write_or_die(fd, line, PEELED_LINE_LENGTH);
2115 }
2116}
2117
7b40d396
MH
2118/*
2119 * An each_ref_entry_fn that writes the entry to a packed-refs file.
2120 */
2121static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)
2122{
2123 int *fd = cb_data;
2124 enum peel_status peel_status = peel_entry(entry, 0);
2125
2126 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
2127 error("internal error: %s is not a valid packed reference!",
2128 entry->name);
2129 write_packed_entry(*fd, entry->name, entry->u.value.sha1,
2130 peel_status == PEEL_PEELED ?
2131 entry->u.value.peeled : NULL);
2132 return 0;
2133}
2134
9f69d297
MH
2135int lock_packed_refs(int flags)
2136{
2137 struct packed_ref_cache *packed_ref_cache;
2138
2139 /* Discard the old cache because it might be invalid: */
2140 clear_packed_ref_cache(&ref_cache);
2141 if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)
2142 return -1;
2143 /* Read the current packed-refs while holding the lock: */
2144 packed_ref_cache = get_packed_ref_cache(&ref_cache);
2145 packed_ref_cache->lock = &packlock;
4f6b83e3
MH
2146 /* Increment the reference count to prevent it from being freed: */
2147 acquire_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2148 return 0;
2149}
2150
2151int commit_packed_refs(void)
2152{
2153 struct packed_ref_cache *packed_ref_cache =
2154 get_packed_ref_cache(&ref_cache);
2155 int error = 0;
2156
2157 if (!packed_ref_cache->lock)
2158 die("internal error: packed-refs not locked");
2159 write_or_die(packed_ref_cache->lock->fd,
2160 PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
2161
2162 do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),
2163 0, write_packed_entry_fn,
2164 &packed_ref_cache->lock->fd);
2165 if (commit_lock_file(packed_ref_cache->lock))
2166 error = -1;
2167 packed_ref_cache->lock = NULL;
4f6b83e3 2168 release_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2169 return error;
2170}
2171
2172void rollback_packed_refs(void)
2173{
2174 struct packed_ref_cache *packed_ref_cache =
2175 get_packed_ref_cache(&ref_cache);
2176
2177 if (!packed_ref_cache->lock)
2178 die("internal error: packed-refs not locked");
2179 rollback_lock_file(packed_ref_cache->lock);
2180 packed_ref_cache->lock = NULL;
4f6b83e3 2181 release_packed_ref_cache(packed_ref_cache);
9f69d297
MH
2182 clear_packed_ref_cache(&ref_cache);
2183}
2184
32d462ce
MH
2185struct ref_to_prune {
2186 struct ref_to_prune *next;
2187 unsigned char sha1[20];
2188 char name[FLEX_ARRAY];
2189};
2190
2191struct pack_refs_cb_data {
2192 unsigned int flags;
267f9a8c 2193 struct ref_dir *packed_refs;
32d462ce 2194 struct ref_to_prune *ref_to_prune;
32d462ce
MH
2195};
2196
267f9a8c
MH
2197/*
2198 * An each_ref_entry_fn that is run over loose references only. If
2199 * the loose reference can be packed, add an entry in the packed ref
2200 * cache. If the reference should be pruned, also add it to
2201 * ref_to_prune in the pack_refs_cb_data.
2202 */
2203static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)
32d462ce
MH
2204{
2205 struct pack_refs_cb_data *cb = cb_data;
f85354b5 2206 enum peel_status peel_status;
267f9a8c 2207 struct ref_entry *packed_entry;
b2a8226d 2208 int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");
32d462ce 2209
267f9a8c
MH
2210 /* ALWAYS pack tags */
2211 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)
32d462ce
MH
2212 return 0;
2213
b2a8226d
MH
2214 /* Do not pack symbolic or broken refs: */
2215 if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))
2216 return 0;
2217
267f9a8c 2218 /* Add a packed ref cache entry equivalent to the loose entry. */
f85354b5 2219 peel_status = peel_entry(entry, 1);
0f29920f 2220 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
f85354b5
MH
2221 die("internal error peeling reference %s (%s)",
2222 entry->name, sha1_to_hex(entry->u.value.sha1));
267f9a8c
MH
2223 packed_entry = find_ref(cb->packed_refs, entry->name);
2224 if (packed_entry) {
2225 /* Overwrite existing packed entry with info from loose entry */
2226 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;
2227 hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);
2228 } else {
2229 packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,
2230 REF_ISPACKED | REF_KNOWS_PEELED, 0);
2231 add_ref(cb->packed_refs, packed_entry);
2232 }
2233 hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);
32d462ce 2234
267f9a8c
MH
2235 /* Schedule the loose reference for pruning if requested. */
2236 if ((cb->flags & PACK_REFS_PRUNE)) {
12e77559 2237 int namelen = strlen(entry->name) + 1;
32d462ce 2238 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
12e77559
MH
2239 hashcpy(n->sha1, entry->u.value.sha1);
2240 strcpy(n->name, entry->name);
32d462ce
MH
2241 n->next = cb->ref_to_prune;
2242 cb->ref_to_prune = n;
2243 }
d66da478
MH
2244 return 0;
2245}
2246
32d462ce
MH
2247/*
2248 * Remove empty parents, but spare refs/ and immediate subdirs.
2249 * Note: munges *name.
2250 */
2251static void try_remove_empty_parents(char *name)
2252{
2253 char *p, *q;
2254 int i;
2255 p = name;
2256 for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */
2257 while (*p && *p != '/')
2258 p++;
2259 /* tolerate duplicate slashes; see check_refname_format() */
2260 while (*p == '/')
2261 p++;
2262 }
2263 for (q = p; *q; q++)
2264 ;
2265 while (1) {
2266 while (q > p && *q != '/')
2267 q--;
2268 while (q > p && *(q-1) == '/')
2269 q--;
2270 if (q == p)
2271 break;
2272 *q = '\0';
2273 if (rmdir(git_path("%s", name)))
2274 break;
2275 }
2276}
2277
2278/* make sure nobody touched the ref, and unlink */
2279static void prune_ref(struct ref_to_prune *r)
2280{
2281 struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
2282
2283 if (lock) {
2284 unlink_or_warn(git_path("%s", r->name));
2285 unlock_ref(lock);
2286 try_remove_empty_parents(r->name);
2287 }
2288}
2289
2290static void prune_refs(struct ref_to_prune *r)
2291{
2292 while (r) {
2293 prune_ref(r);
2294 r = r->next;
2295 }
2296}
2297
32d462ce
MH
2298int pack_refs(unsigned int flags)
2299{
32d462ce
MH
2300 struct pack_refs_cb_data cbdata;
2301
2302 memset(&cbdata, 0, sizeof(cbdata));
2303 cbdata.flags = flags;
2304
9f69d297 2305 lock_packed_refs(LOCK_DIE_ON_ERROR);
267f9a8c
MH
2306 cbdata.packed_refs = get_packed_refs(&ref_cache);
2307
2308 do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,
2309 pack_if_possible_fn, &cbdata);
32d462ce 2310
9f69d297 2311 if (commit_packed_refs())
32d462ce 2312 die_errno("unable to overwrite old ref-pack file");
9f69d297 2313
32d462ce
MH
2314 prune_refs(cbdata.ref_to_prune);
2315 return 0;
2316}
2317
7b40d396
MH
2318/*
2319 * If entry is no longer needed in packed-refs, add it to the string
2320 * list pointed to by cb_data. Reasons for deleting entries:
2321 *
2322 * - Entry is broken.
2323 * - Entry is overridden by a loose ref.
2324 * - Entry does not point at a valid object.
2325 *
2326 * In the first and third cases, also emit an error message because these
2327 * are indications of repository corruption.
2328 */
2329static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)
c0277d15 2330{
7b40d396 2331 struct string_list *refs_to_delete = cb_data;
fec3137f 2332
ab292bc4
MH
2333 if (entry->flag & REF_ISBROKEN) {
2334 /* This shouldn't happen to packed refs. */
2335 error("%s is broken!", entry->name);
7b40d396 2336 string_list_append(refs_to_delete, entry->name);
c0277d15 2337 return 0;
ab292bc4
MH
2338 }
2339 if (!has_sha1_file(entry->u.value.sha1)) {
2340 unsigned char sha1[20];
2341 int flags;
2342
2343 if (read_ref_full(entry->name, sha1, 0, &flags))
2344 /* We should at least have found the packed ref. */
2345 die("Internal error");
7b40d396 2346 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {
ab292bc4
MH
2347 /*
2348 * This packed reference is overridden by a
2349 * loose reference, so it is OK that its value
2350 * is no longer valid; for example, it might
2351 * refer to an object that has been garbage
2352 * collected. For this purpose we don't even
2353 * care whether the loose reference itself is
2354 * invalid, broken, symbolic, etc. Silently
7b40d396 2355 * remove the packed reference.
ab292bc4 2356 */
7b40d396 2357 string_list_append(refs_to_delete, entry->name);
ab292bc4 2358 return 0;
7b40d396 2359 }
ab292bc4
MH
2360 /*
2361 * There is no overriding loose reference, so the fact
2362 * that this reference doesn't refer to a valid object
2363 * indicates some kind of repository corruption.
2364 * Report the problem, then omit the reference from
2365 * the output.
2366 */
2367 error("%s does not point to a valid object!", entry->name);
7b40d396 2368 string_list_append(refs_to_delete, entry->name);
ab292bc4
MH
2369 return 0;
2370 }
2371
d66da478
MH
2372 return 0;
2373}
2374
c0277d15
JH
2375static int repack_without_ref(const char *refname)
2376{
7618fd80 2377 struct ref_dir *packed;
7b40d396
MH
2378 struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
2379 struct string_list_item *ref_to_delete;
7618fd80
MH
2380
2381 if (!get_packed_ref(refname))
2382 return 0; /* refname does not exist in packed refs */
2383
9f69d297 2384 if (lock_packed_refs(0)) {
1b018fd9 2385 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 2386 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 2387 }
9da31cb0 2388 packed = get_packed_refs(&ref_cache);
7b40d396
MH
2389
2390 /* Remove refname from the cache: */
506a760d
MH
2391 if (remove_entry(packed, refname) == -1) {
2392 /*
2393 * The packed entry disappeared while we were
2394 * acquiring the lock.
2395 */
9f69d297 2396 rollback_packed_refs();
506a760d
MH
2397 return 0;
2398 }
7b40d396
MH
2399
2400 /* Remove any other accumulated cruft: */
2401 do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);
2402 for_each_string_list_item(ref_to_delete, &refs_to_delete) {
2403 if (remove_entry(packed, ref_to_delete->string) == -1)
2404 die("internal error");
2405 }
2406
2407 /* Write what remains: */
9f69d297 2408 return commit_packed_refs();
c0277d15
JH
2409}
2410
eca35a25 2411int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
2412{
2413 struct ref_lock *lock;
eca35a25 2414 int err, i = 0, ret = 0, flag = 0;
c0277d15 2415
547d058f 2416 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
c0277d15
JH
2417 if (!lock)
2418 return 1;
045a476f 2419 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 2420 /* loose */
547d058f
RS
2421 i = strlen(lock->lk->filename) - 5; /* .lock */
2422 lock->lk->filename[i] = 0;
2423 err = unlink_or_warn(lock->lk->filename);
691f1a28 2424 if (err && errno != ENOENT)
c0277d15 2425 ret = 1;
691f1a28 2426
547d058f 2427 lock->lk->filename[i] = '.';
c0277d15
JH
2428 }
2429 /* removing the loose one could have resurrected an earlier
2430 * packed one. Also, if it was not loose we need to repack
2431 * without it.
2432 */
b274a714 2433 ret |= repack_without_ref(lock->ref_name);
c0277d15 2434
691f1a28 2435 unlink_or_warn(git_path("logs/%s", lock->ref_name));
9da31cb0 2436 clear_loose_ref_cache(&ref_cache);
c0277d15
JH
2437 unlock_ref(lock);
2438 return ret;
4bd18c43
SP
2439}
2440
765c2258
PH
2441/*
2442 * People using contrib's git-new-workdir have .git/logs/refs ->
2443 * /some/other/path/.git/logs/refs, and that may live on another device.
2444 *
2445 * IOW, to avoid cross device rename errors, the temporary renamed log must
2446 * live into logs/refs.
2447 */
2448#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
2449
dfefa935 2450int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 2451{
c976d415
LH
2452 unsigned char sha1[20], orig_sha1[20];
2453 int flag = 0, logmoved = 0;
2454 struct ref_lock *lock;
c976d415 2455 struct stat loginfo;
dfefa935 2456 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 2457 const char *symref = NULL;
c976d415 2458
450d4c0f 2459 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 2460 return error("reflog for %s is a symlink", oldrefname);
c976d415 2461
8d68493f 2462 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 2463 if (flag & REF_ISSYMREF)
fa58186c 2464 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 2465 oldrefname);
eca35a25 2466 if (!symref)
dfefa935 2467 return error("refname %s not found", oldrefname);
c976d415 2468
9da31cb0 2469 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))
c976d415
LH
2470 return 1;
2471
9da31cb0 2472 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))
c976d415
LH
2473 return 1;
2474
dfefa935 2475 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 2476 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 2477 oldrefname, strerror(errno));
c976d415 2478
dfefa935
MH
2479 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
2480 error("unable to delete old %s", oldrefname);
c976d415
LH
2481 goto rollback;
2482 }
2483
dfefa935
MH
2484 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
2485 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 2486 if (errno==EISDIR) {
dfefa935
MH
2487 if (remove_empty_directories(git_path("%s", newrefname))) {
2488 error("Directory not empty: %s", newrefname);
c976d415
LH
2489 goto rollback;
2490 }
2491 } else {
dfefa935 2492 error("unable to delete existing %s", newrefname);
c976d415
LH
2493 goto rollback;
2494 }
2495 }
2496
dfefa935
MH
2497 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
2498 error("unable to create directory for %s", newrefname);
c976d415
LH
2499 goto rollback;
2500 }
2501
2502 retry:
dfefa935 2503 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
2504 if (errno==EISDIR || errno==ENOTDIR) {
2505 /*
2506 * rename(a, b) when b is an existing
2507 * directory ought to result in ISDIR, but
2508 * Solaris 5.8 gives ENOTDIR. Sheesh.
2509 */
dfefa935
MH
2510 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
2511 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
2512 goto rollback;
2513 }
2514 goto retry;
2515 } else {
765c2258 2516 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 2517 newrefname, strerror(errno));
c976d415
LH
2518 goto rollback;
2519 }
2520 }
2521 logmoved = log;
2522
dfefa935 2523 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 2524 if (!lock) {
dfefa935 2525 error("unable to lock %s for update", newrefname);
c976d415
LH
2526 goto rollback;
2527 }
c976d415
LH
2528 lock->force_write = 1;
2529 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 2530 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 2531 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
2532 goto rollback;
2533 }
2534
2535 return 0;
2536
2537 rollback:
dfefa935 2538 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 2539 if (!lock) {
dfefa935 2540 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
2541 goto rollbacklog;
2542 }
2543
2544 lock->force_write = 1;
2545 flag = log_all_ref_updates;
2546 log_all_ref_updates = 0;
2547 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 2548 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
2549 log_all_ref_updates = flag;
2550
2551 rollbacklog:
dfefa935 2552 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 2553 error("unable to restore logfile %s from %s: %s",
dfefa935 2554 oldrefname, newrefname, strerror(errno));
c976d415 2555 if (!logmoved && log &&
dfefa935 2556 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 2557 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 2558 oldrefname, strerror(errno));
c976d415
LH
2559
2560 return 1;
2561}
2562
435fc852 2563int close_ref(struct ref_lock *lock)
b531394d
BC
2564{
2565 if (close_lock_file(lock->lk))
2566 return -1;
2567 lock->lock_fd = -1;
2568 return 0;
2569}
2570
435fc852 2571int commit_ref(struct ref_lock *lock)
b531394d
BC
2572{
2573 if (commit_lock_file(lock->lk))
2574 return -1;
2575 lock->lock_fd = -1;
2576 return 0;
2577}
2578
e5f38ec3 2579void unlock_ref(struct ref_lock *lock)
4bd18c43 2580{
4ed7cd3a
BC
2581 /* Do not free lock->lk -- atexit() still looks at them */
2582 if (lock->lk)
2583 rollback_lock_file(lock->lk);
434cd0cd 2584 free(lock->ref_name);
1655707c 2585 free(lock->orig_ref_name);
4bd18c43
SP
2586 free(lock);
2587}
2588
0ec29a47
JH
2589/*
2590 * copy the reflog message msg to buf, which has been allocated sufficiently
2591 * large, while cleaning up the whitespaces. Especially, convert LF to space,
2592 * because reflog file is one line per entry.
2593 */
2594static int copy_msg(char *buf, const char *msg)
2595{
2596 char *cp = buf;
2597 char c;
2598 int wasspace = 1;
2599
2600 *cp++ = '\t';
2601 while ((c = *msg++)) {
2602 if (wasspace && isspace(c))
2603 continue;
2604 wasspace = isspace(c);
2605 if (wasspace)
2606 c = ' ';
2607 *cp++ = c;
2608 }
2609 while (buf < cp && isspace(cp[-1]))
2610 cp--;
2611 *cp++ = '\n';
2612 return cp - buf;
2613}
2614
dfefa935 2615int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 2616{
859c3017 2617 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 2618
dfefa935 2619 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 2620 if (log_all_ref_updates &&
dfefa935
MH
2621 (!prefixcmp(refname, "refs/heads/") ||
2622 !prefixcmp(refname, "refs/remotes/") ||
2623 !prefixcmp(refname, "refs/notes/") ||
2624 !strcmp(refname, "HEAD"))) {
157aaea5 2625 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 2626 return error("unable to create directory for %s",
157aaea5 2627 logfile);
6de08ae6
SP
2628 oflags |= O_CREAT;
2629 }
2630
157aaea5 2631 logfd = open(logfile, oflags, 0666);
6de08ae6 2632 if (logfd < 0) {
1974bf62 2633 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 2634 return 0;
3b463c3f
JH
2635
2636 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 2637 if (remove_empty_directories(logfile)) {
3b463c3f 2638 return error("There are still logs under '%s'",
157aaea5 2639 logfile);
3b463c3f 2640 }
157aaea5 2641 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
2642 }
2643
2644 if (logfd < 0)
2645 return error("Unable to append to %s: %s",
157aaea5 2646 logfile, strerror(errno));
6de08ae6
SP
2647 }
2648
157aaea5 2649 adjust_shared_perm(logfile);
859c3017
EM
2650 close(logfd);
2651 return 0;
2652}
443b92b6 2653
dfefa935 2654static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
2655 const unsigned char *new_sha1, const char *msg)
2656{
2657 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2658 unsigned maxlen, len;
2659 int msglen;
157aaea5 2660 char log_file[PATH_MAX];
859c3017
EM
2661 char *logrec;
2662 const char *committer;
2663
2664 if (log_all_ref_updates < 0)
2665 log_all_ref_updates = !is_bare_repository();
2666
dfefa935 2667 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
2668 if (result)
2669 return result;
2670
2671 logfd = open(log_file, oflags);
2672 if (logfd < 0)
2673 return 0;
0ec29a47 2674 msglen = msg ? strlen(msg) : 0;
774751a8 2675 committer = git_committer_info(0);
8ac65937
JH
2676 maxlen = strlen(committer) + msglen + 100;
2677 logrec = xmalloc(maxlen);
2678 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
2679 sha1_to_hex(old_sha1),
2680 sha1_to_hex(new_sha1),
8ac65937
JH
2681 committer);
2682 if (msglen)
0ec29a47 2683 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 2684 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 2685 free(logrec);
91c8d590 2686 if (close(logfd) != 0 || written != len)
9a13f0b7 2687 return error("Unable to append to %s", log_file);
6de08ae6
SP
2688 return 0;
2689}
2690
c3b0dec5
LT
2691static int is_branch(const char *refname)
2692{
2693 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2694}
2695
4bd18c43
SP
2696int write_ref_sha1(struct ref_lock *lock,
2697 const unsigned char *sha1, const char *logmsg)
2698{
2699 static char term = '\n';
c3b0dec5 2700 struct object *o;
4bd18c43
SP
2701
2702 if (!lock)
95fc7512 2703 return -1;
a89fccd2 2704 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
2705 unlock_ref(lock);
2706 return 0;
95fc7512 2707 }
c3b0dec5
LT
2708 o = parse_object(sha1);
2709 if (!o) {
7be8b3ba 2710 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
2711 lock->ref_name, sha1_to_hex(sha1));
2712 unlock_ref(lock);
2713 return -1;
2714 }
2715 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2716 error("Trying to write non-commit object %s to branch %s",
2717 sha1_to_hex(sha1), lock->ref_name);
2718 unlock_ref(lock);
2719 return -1;
2720 }
93822c22
AW
2721 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2722 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 2723 || close_ref(lock) < 0) {
c33d5174 2724 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
2725 unlock_ref(lock);
2726 return -1;
2727 }
9da31cb0 2728 clear_loose_ref_cache(&ref_cache);
bd104db1
NP
2729 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2730 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2731 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
2732 unlock_ref(lock);
2733 return -1;
2734 }
605fac8b
NP
2735 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2736 /*
2737 * Special hack: If a branch is updated directly and HEAD
2738 * points to it (may happen on the remote side of a push
2739 * for example) then logically the HEAD reflog should be
2740 * updated too.
2741 * A generic solution implies reverse symref information,
2742 * but finding all symrefs pointing to the given branch
2743 * would be rather costly for this rare event (the direct
2744 * update of a branch) to be worth it. So let's cheat and
2745 * check with HEAD only which should cover 99% of all usage
2746 * scenarios (even 100% of the default ones).
2747 */
2748 unsigned char head_sha1[20];
2749 int head_flag;
2750 const char *head_ref;
8cad4744 2751 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2752 if (head_ref && (head_flag & REF_ISSYMREF) &&
2753 !strcmp(head_ref, lock->ref_name))
2754 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2755 }
b531394d 2756 if (commit_ref(lock)) {
434cd0cd 2757 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2758 unlock_ref(lock);
2759 return -1;
2760 }
4bd18c43
SP
2761 unlock_ref(lock);
2762 return 0;
95fc7512 2763}
d556fae2 2764
8b5157e4
NP
2765int create_symref(const char *ref_target, const char *refs_heads_master,
2766 const char *logmsg)
41b625b0
NP
2767{
2768 const char *lockpath;
2769 char ref[1000];
2770 int fd, len, written;
a4f34cbb 2771 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2772 unsigned char old_sha1[20], new_sha1[20];
2773
2774 if (logmsg && read_ref(ref_target, old_sha1))
2775 hashclr(old_sha1);
41b625b0 2776
d48744d1
JH
2777 if (safe_create_leading_directories(git_HEAD) < 0)
2778 return error("unable to create directory for %s", git_HEAD);
2779
41b625b0
NP
2780#ifndef NO_SYMLINK_HEAD
2781 if (prefer_symlink_refs) {
2782 unlink(git_HEAD);
2783 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2784 goto done;
41b625b0
NP
2785 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2786 }
2787#endif
2788
2789 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2790 if (sizeof(ref) <= len) {
2791 error("refname too long: %s", refs_heads_master);
47fc52e2 2792 goto error_free_return;
41b625b0
NP
2793 }
2794 lockpath = mkpath("%s.lock", git_HEAD);
2795 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2796 if (fd < 0) {
2797 error("Unable to open %s for writing", lockpath);
47fc52e2 2798 goto error_free_return;
41b625b0
NP
2799 }
2800 written = write_in_full(fd, ref, len);
91c8d590 2801 if (close(fd) != 0 || written != len) {
41b625b0 2802 error("Unable to write to %s", lockpath);
47fc52e2 2803 goto error_unlink_return;
41b625b0
NP
2804 }
2805 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2806 error("Unable to create %s", git_HEAD);
47fc52e2 2807 goto error_unlink_return;
41b625b0
NP
2808 }
2809 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2810 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2811 error_unlink_return:
691f1a28 2812 unlink_or_warn(lockpath);
47fc52e2
JH
2813 error_free_return:
2814 free(git_HEAD);
2815 return -1;
41b625b0 2816 }
8b5157e4 2817
ee96d11b 2818#ifndef NO_SYMLINK_HEAD
8b5157e4 2819 done:
ee96d11b 2820#endif
8b5157e4
NP
2821 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2822 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2823
47fc52e2 2824 free(git_HEAD);
41b625b0
NP
2825 return 0;
2826}
2827
16d7cc90
JH
2828static char *ref_msg(const char *line, const char *endp)
2829{
2830 const char *ep;
16d7cc90 2831 line += 82;
182af834
PH
2832 ep = memchr(line, '\n', endp - line);
2833 if (!ep)
2834 ep = endp;
2835 return xmemdupz(line, ep - line);
16d7cc90
JH
2836}
2837
dfefa935
MH
2838int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2839 unsigned char *sha1, char **msg,
2840 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2841{
e5229042 2842 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2843 char *tz_c;
e29cb53a 2844 int logfd, tz, reccnt = 0;
d556fae2
SP
2845 struct stat st;
2846 unsigned long date;
e5229042 2847 unsigned char logged_sha1[20];
cb48cb58 2848 void *log_mapped;
dc49cd76 2849 size_t mapsz;
d556fae2 2850
dfefa935 2851 logfile = git_path("logs/%s", refname);
d556fae2
SP
2852 logfd = open(logfile, O_RDONLY, 0);
2853 if (logfd < 0)
d824cbba 2854 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2855 fstat(logfd, &st);
2856 if (!st.st_size)
2857 die("Log %s is empty.", logfile);
dc49cd76
SP
2858 mapsz = xsize_t(st.st_size);
2859 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2860 logdata = log_mapped;
d556fae2
SP
2861 close(logfd);
2862
e5229042 2863 lastrec = NULL;
d556fae2
SP
2864 rec = logend = logdata + st.st_size;
2865 while (logdata < rec) {
e29cb53a 2866 reccnt++;
d556fae2
SP
2867 if (logdata < rec && *(rec-1) == '\n')
2868 rec--;
e5229042
SP
2869 lastgt = NULL;
2870 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2871 rec--;
e5229042
SP
2872 if (*rec == '>')
2873 lastgt = rec;
2874 }
2875 if (!lastgt)
d556fae2 2876 die("Log %s is corrupt.", logfile);
e5229042 2877 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2878 if (date <= at_time || cnt == 0) {
76a44c5c 2879 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2880 if (msg)
2881 *msg = ref_msg(rec, logend);
2882 if (cutoff_time)
2883 *cutoff_time = date;
2884 if (cutoff_tz)
2885 *cutoff_tz = tz;
2886 if (cutoff_cnt)
76a44c5c 2887 *cutoff_cnt = reccnt - 1;
e5229042
SP
2888 if (lastrec) {
2889 if (get_sha1_hex(lastrec, logged_sha1))
2890 die("Log %s is corrupt.", logfile);
2891 if (get_sha1_hex(rec + 41, sha1))
2892 die("Log %s is corrupt.", logfile);
a89fccd2 2893 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2894 warning("Log %s has gap after %s.",
73013afd 2895 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2896 }
e5f38ec3
JH
2897 }
2898 else if (date == at_time) {
e5229042
SP
2899 if (get_sha1_hex(rec + 41, sha1))
2900 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2901 }
2902 else {
e5229042
SP
2903 if (get_sha1_hex(rec + 41, logged_sha1))
2904 die("Log %s is corrupt.", logfile);
a89fccd2 2905 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2906 warning("Log %s unexpectedly ended on %s.",
73013afd 2907 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2908 }
2909 }
dc49cd76 2910 munmap(log_mapped, mapsz);
d556fae2
SP
2911 return 0;
2912 }
e5229042 2913 lastrec = rec;
ab2a1a32
JH
2914 if (cnt > 0)
2915 cnt--;
d556fae2
SP
2916 }
2917
e5229042
SP
2918 rec = logdata;
2919 while (rec < logend && *rec != '>' && *rec != '\n')
2920 rec++;
2921 if (rec == logend || *rec == '\n')
d556fae2 2922 die("Log %s is corrupt.", logfile);
e5229042 2923 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2924 tz = strtoul(tz_c, NULL, 10);
2925 if (get_sha1_hex(logdata, sha1))
2926 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2927 if (is_null_sha1(sha1)) {
2928 if (get_sha1_hex(logdata + 41, sha1))
2929 die("Log %s is corrupt.", logfile);
2930 }
16d7cc90
JH
2931 if (msg)
2932 *msg = ref_msg(logdata, logend);
dc49cd76 2933 munmap(log_mapped, mapsz);
16d7cc90
JH
2934
2935 if (cutoff_time)
2936 *cutoff_time = date;
2937 if (cutoff_tz)
2938 *cutoff_tz = tz;
2939 if (cutoff_cnt)
2940 *cutoff_cnt = reccnt;
2941 return 1;
d556fae2 2942}
2ff81662 2943
9a7a183b
JH
2944static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)
2945{
2946 unsigned char osha1[20], nsha1[20];
2947 char *email_end, *message;
2948 unsigned long timestamp;
2949 int tz;
2950
2951 /* old SP new SP name <email> SP time TAB msg LF */
2952 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||
2953 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||
2954 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||
2955 !(email_end = strchr(sb->buf + 82, '>')) ||
2956 email_end[1] != ' ' ||
2957 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2958 !message || message[0] != ' ' ||
2959 (message[1] != '+' && message[1] != '-') ||
2960 !isdigit(message[2]) || !isdigit(message[3]) ||
2961 !isdigit(message[4]) || !isdigit(message[5]))
2962 return 0; /* corrupt? */
2963 email_end[1] = '\0';
2964 tz = strtol(message + 1, NULL, 10);
2965 if (message[6] != '\t')
2966 message += 6;
2967 else
2968 message += 7;
2969 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);
2970}
2971
98f85ff4
JH
2972static char *find_beginning_of_line(char *bob, char *scan)
2973{
2974 while (bob < scan && *(--scan) != '\n')
2975 ; /* keep scanning backwards */
2976 /*
2977 * Return either beginning of the buffer, or LF at the end of
2978 * the previous line.
2979 */
2980 return scan;
2981}
2982
2983int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)
2ff81662 2984{
8ca78803 2985 struct strbuf sb = STRBUF_INIT;
98f85ff4
JH
2986 FILE *logfp;
2987 long pos;
2988 int ret = 0, at_tail = 1;
2ff81662 2989
7ae07c1b 2990 logfp = fopen(git_path("logs/%s", refname), "r");
2ff81662 2991 if (!logfp)
883d60fa 2992 return -1;
101d15e0 2993
98f85ff4
JH
2994 /* Jump to the end */
2995 if (fseek(logfp, 0, SEEK_END) < 0)
2996 return error("cannot seek back reflog for %s: %s",
2997 refname, strerror(errno));
2998 pos = ftell(logfp);
2999 while (!ret && 0 < pos) {
3000 int cnt;
3001 size_t nread;
3002 char buf[BUFSIZ];
3003 char *endp, *scanp;
3004
3005 /* Fill next block from the end */
3006 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;
3007 if (fseek(logfp, pos - cnt, SEEK_SET))
3008 return error("cannot seek back reflog for %s: %s",
3009 refname, strerror(errno));
3010 nread = fread(buf, cnt, 1, logfp);
e4ca819a 3011 if (nread != 1)
98f85ff4
JH
3012 return error("cannot read %d bytes from reflog for %s: %s",
3013 cnt, refname, strerror(errno));
3014 pos -= cnt;
3015
3016 scanp = endp = buf + cnt;
3017 if (at_tail && scanp[-1] == '\n')
3018 /* Looking at the final LF at the end of the file */
3019 scanp--;
3020 at_tail = 0;
3021
3022 while (buf < scanp) {
3023 /*
3024 * terminating LF of the previous line, or the beginning
3025 * of the buffer.
3026 */
3027 char *bp;
3028
3029 bp = find_beginning_of_line(buf, scanp);
3030
3031 if (*bp != '\n') {
3032 strbuf_splice(&sb, 0, 0, buf, endp - buf);
3033 if (pos)
3034 break; /* need to fill another block */
3035 scanp = buf - 1; /* leave loop */
3036 } else {
3037 /*
3038 * (bp + 1) thru endp is the beginning of the
3039 * current line we have in sb
3040 */
3041 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
3042 scanp = bp;
3043 endp = bp + 1;
3044 }
3045 ret = show_one_reflog_ent(&sb, fn, cb_data);
3046 strbuf_reset(&sb);
3047 if (ret)
3048 break;
9d33f7c2 3049 }
101d15e0 3050
2ff81662 3051 }
98f85ff4 3052 if (!ret && sb.len)
9a7a183b 3053 ret = show_one_reflog_ent(&sb, fn, cb_data);
98f85ff4 3054
2ff81662 3055 fclose(logfp);
8ca78803 3056 strbuf_release(&sb);
2266bf27 3057 return ret;
2ff81662 3058}
e29cb53a 3059
dfefa935 3060int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 3061{
98f85ff4
JH
3062 FILE *logfp;
3063 struct strbuf sb = STRBUF_INIT;
3064 int ret = 0;
3065
3066 logfp = fopen(git_path("logs/%s", refname), "r");
3067 if (!logfp)
3068 return -1;
101d15e0 3069
98f85ff4
JH
3070 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))
3071 ret = show_one_reflog_ent(&sb, fn, cb_data);
3072 fclose(logfp);
3073 strbuf_release(&sb);
3074 return ret;
3075}
989c0e5d
MH
3076/*
3077 * Call fn for each reflog in the namespace indicated by name. name
3078 * must be empty or end with '/'. Name will be used as a scratch
3079 * space, but its contents will be restored before return.
3080 */
3081static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 3082{
989c0e5d 3083 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 3084 int retval = 0;
93c603fc 3085 struct dirent *de;
989c0e5d 3086 int oldlen = name->len;
eb8381c8 3087
93c603fc 3088 if (!d)
989c0e5d 3089 return name->len ? errno : 0;
eb8381c8 3090
93c603fc
MH
3091 while ((de = readdir(d)) != NULL) {
3092 struct stat st;
eb8381c8 3093
93c603fc
MH
3094 if (de->d_name[0] == '.')
3095 continue;
93c603fc
MH
3096 if (has_extension(de->d_name, ".lock"))
3097 continue;
989c0e5d
MH
3098 strbuf_addstr(name, de->d_name);
3099 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
3100 ; /* silently ignore */
93c603fc 3101 } else {
eb8381c8 3102 if (S_ISDIR(st.st_mode)) {
989c0e5d
MH
3103 strbuf_addch(name, '/');
3104 retval = do_for_each_reflog(name, fn, cb_data);
eb8381c8
NP
3105 } else {
3106 unsigned char sha1[20];
989c0e5d
MH
3107 if (read_ref_full(name->buf, sha1, 0, NULL))
3108 retval = error("bad ref for %s", name->buf);
eb8381c8 3109 else
989c0e5d 3110 retval = fn(name->buf, sha1, 0, cb_data);
eb8381c8
NP
3111 }
3112 if (retval)
3113 break;
3114 }
989c0e5d 3115 strbuf_setlen(name, oldlen);
eb8381c8 3116 }
93c603fc 3117 closedir(d);
eb8381c8
NP
3118 return retval;
3119}
3120
3121int for_each_reflog(each_ref_fn fn, void *cb_data)
3122{
989c0e5d
MH
3123 int retval;
3124 struct strbuf name;
3125 strbuf_init(&name, PATH_MAX);
3126 retval = do_for_each_reflog(&name, fn, cb_data);
3127 strbuf_release(&name);
3128 return retval;
eb8381c8 3129}
3d9f037c
CR
3130
3131int update_ref(const char *action, const char *refname,
3132 const unsigned char *sha1, const unsigned char *oldval,
3133 int flags, enum action_on_err onerr)
3134{
3135 static struct ref_lock *lock;
3136 lock = lock_any_ref_for_update(refname, oldval, flags);
3137 if (!lock) {
3138 const char *str = "Cannot lock the ref '%s'.";
3139 switch (onerr) {
3140 case MSG_ON_ERR: error(str, refname); break;
3141 case DIE_ON_ERR: die(str, refname); break;
3142 case QUIET_ON_ERR: break;
3143 }
3144 return 1;
3145 }
3146 if (write_ref_sha1(lock, sha1, action) < 0) {
3147 const char *str = "Cannot update the ref '%s'.";
3148 switch (onerr) {
3149 case MSG_ON_ERR: error(str, refname); break;
3150 case DIE_ON_ERR: die(str, refname); break;
3151 case QUIET_ON_ERR: break;
3152 }
3153 return 1;
3154 }
3155 return 0;
3156}
cda69f48 3157
5483f799 3158struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
3159{
3160 for ( ; list; list = list->next)
3161 if (!strcmp(list->name, name))
5483f799 3162 return (struct ref *)list;
cda69f48
JK
3163 return NULL;
3164}
7c2b3029
JK
3165
3166/*
3167 * generate a format suitable for scanf from a ref_rev_parse_rules
3168 * rule, that is replace the "%.*s" spec with a "%s" spec
3169 */
3170static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
3171{
3172 char *spec;
3173
3174 spec = strstr(rule, "%.*s");
3175 if (!spec || strstr(spec + 4, "%.*s"))
3176 die("invalid rule in ref_rev_parse_rules: %s", rule);
3177
3178 /* copy all until spec */
3179 strncpy(scanf_fmt, rule, spec - rule);
3180 scanf_fmt[spec - rule] = '\0';
3181 /* copy new spec */
3182 strcat(scanf_fmt, "%s");
3183 /* copy remaining rule */
3184 strcat(scanf_fmt, spec + 4);
3185
3186 return;
3187}
3188
dfefa935 3189char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
3190{
3191 int i;
3192 static char **scanf_fmts;
3193 static int nr_rules;
3194 char *short_name;
3195
3196 /* pre generate scanf formats from ref_rev_parse_rules[] */
3197 if (!nr_rules) {
3198 size_t total_len = 0;
3199
3200 /* the rule list is NULL terminated, count them first */
3201 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
3202 /* no +1 because strlen("%s") < strlen("%.*s") */
3203 total_len += strlen(ref_rev_parse_rules[nr_rules]);
3204
3205 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
3206
3207 total_len = 0;
3208 for (i = 0; i < nr_rules; i++) {
3209 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
3210 + total_len;
3211 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
3212 total_len += strlen(ref_rev_parse_rules[i]);
3213 }
3214 }
3215
3216 /* bail out if there are no rules */
3217 if (!nr_rules)
dfefa935 3218 return xstrdup(refname);
7c2b3029 3219
dfefa935
MH
3220 /* buffer for scanf result, at most refname must fit */
3221 short_name = xstrdup(refname);
7c2b3029
JK
3222
3223 /* skip first rule, it will always match */
3224 for (i = nr_rules - 1; i > 0 ; --i) {
3225 int j;
6e7b3309 3226 int rules_to_fail = i;
7c2b3029
JK
3227 int short_name_len;
3228
dfefa935 3229 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
3230 continue;
3231
3232 short_name_len = strlen(short_name);
3233
6e7b3309
BW
3234 /*
3235 * in strict mode, all (except the matched one) rules
3236 * must fail to resolve to a valid non-ambiguous ref
3237 */
3238 if (strict)
3239 rules_to_fail = nr_rules;
3240
7c2b3029
JK
3241 /*
3242 * check if the short name resolves to a valid ref,
3243 * but use only rules prior to the matched one
3244 */
6e7b3309 3245 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 3246 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
3247 char refname[PATH_MAX];
3248
6e7b3309
BW
3249 /* skip matched rule */
3250 if (i == j)
3251 continue;
3252
7c2b3029
JK
3253 /*
3254 * the short name is ambiguous, if it resolves
3255 * (with this previous rule) to a valid ref
3256 * read_ref() returns 0 on success
3257 */
3258 mksnpath(refname, sizeof(refname),
3259 rule, short_name_len, short_name);
c6893323 3260 if (ref_exists(refname))
7c2b3029
JK
3261 break;
3262 }
3263
3264 /*
3265 * short name is non-ambiguous if all previous rules
3266 * haven't resolved to a valid ref
3267 */
6e7b3309 3268 if (j == rules_to_fail)
7c2b3029
JK
3269 return short_name;
3270 }
3271
3272 free(short_name);
dfefa935 3273 return xstrdup(refname);
7c2b3029 3274}
daebaa78
JH
3275
3276static struct string_list *hide_refs;
3277
3278int parse_hide_refs_config(const char *var, const char *value, const char *section)
3279{
3280 if (!strcmp("transfer.hiderefs", var) ||
3281 /* NEEDSWORK: use parse_config_key() once both are merged */
3282 (!prefixcmp(var, section) && var[strlen(section)] == '.' &&
3283 !strcmp(var + strlen(section), ".hiderefs"))) {
3284 char *ref;
3285 int len;
3286
3287 if (!value)
3288 return config_error_nonbool(var);
3289 ref = xstrdup(value);
3290 len = strlen(ref);
3291 while (len && ref[len - 1] == '/')
3292 ref[--len] = '\0';
3293 if (!hide_refs) {
3294 hide_refs = xcalloc(1, sizeof(*hide_refs));
3295 hide_refs->strdup_strings = 1;
3296 }
3297 string_list_append(hide_refs, ref);
3298 }
3299 return 0;
3300}
3301
3302int ref_is_hidden(const char *refname)
3303{
3304 struct string_list_item *item;
3305
3306 if (!hide_refs)
3307 return 0;
3308 for_each_string_list_item(item, hide_refs) {
3309 int len;
3310 if (prefixcmp(refname, item->string))
3311 continue;
3312 len = strlen(item->string);
3313 if (!refname[len] || refname[len] == '/')
3314 return 1;
3315 }
3316 return 0;
3317}