refs: document do_for_each_ref() and do_one_ref()
[git/git.git] / refs.c
CommitLineData
95fc7512 1#include "cache.h"
85023577 2#include "refs.h"
cf0adba7
JH
3#include "object.h"
4#include "tag.h"
7155b727 5#include "dir.h"
95fc7512 6
bc5fd6d3
MH
7/*
8 * Make sure "ref" is something reasonable to have under ".git/refs/";
9 * We do not like it if:
10 *
11 * - any path component of it begins with ".", or
12 * - it has double dots "..", or
13 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
14 * - it ends with a "/".
15 * - it ends with ".lock"
16 * - it contains a "\" (backslash)
17 */
f4204ab9 18
bc5fd6d3
MH
19/* Return true iff ch is not allowed in reference names. */
20static inline int bad_ref_char(int ch)
21{
22 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
23 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
24 return 1;
25 /* 2.13 Pattern Matching Notation */
26 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
27 return 1;
28 return 0;
29}
30
31/*
32 * Try to read one refname component from the front of refname. Return
33 * the length of the component found, or -1 if the component is not
34 * legal.
35 */
36static int check_refname_component(const char *refname, int flags)
37{
38 const char *cp;
39 char last = '\0';
40
41 for (cp = refname; ; cp++) {
42 char ch = *cp;
43 if (ch == '\0' || ch == '/')
44 break;
45 if (bad_ref_char(ch))
46 return -1; /* Illegal character in refname. */
47 if (last == '.' && ch == '.')
48 return -1; /* Refname contains "..". */
49 if (last == '@' && ch == '{')
50 return -1; /* Refname contains "@{". */
51 last = ch;
52 }
53 if (cp == refname)
dac529e4 54 return 0; /* Component has zero length. */
bc5fd6d3
MH
55 if (refname[0] == '.') {
56 if (!(flags & REFNAME_DOT_COMPONENT))
57 return -1; /* Component starts with '.'. */
58 /*
59 * Even if leading dots are allowed, don't allow "."
60 * as a component (".." is prevented by a rule above).
61 */
62 if (refname[1] == '\0')
63 return -1; /* Component equals ".". */
64 }
65 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
66 return -1; /* Refname ends with ".lock". */
67 return cp - refname;
68}
69
70int check_refname_format(const char *refname, int flags)
71{
72 int component_len, component_count = 0;
73
74 while (1) {
75 /* We are at the start of a path component. */
76 component_len = check_refname_component(refname, flags);
dac529e4 77 if (component_len <= 0) {
bc5fd6d3
MH
78 if ((flags & REFNAME_REFSPEC_PATTERN) &&
79 refname[0] == '*' &&
80 (refname[1] == '\0' || refname[1] == '/')) {
81 /* Accept one wildcard as a full refname component. */
82 flags &= ~REFNAME_REFSPEC_PATTERN;
83 component_len = 1;
84 } else {
85 return -1;
86 }
87 }
88 component_count++;
89 if (refname[component_len] == '\0')
90 break;
91 /* Skip to next component. */
92 refname += component_len + 1;
93 }
94
95 if (refname[component_len - 1] == '.')
96 return -1; /* Refname ends with '.'. */
97 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
98 return -1; /* Refname has only one component. */
99 return 0;
100}
101
102struct ref_entry;
e1e22e37 103
28e6a34e
MH
104/*
105 * Information used (along with the information in ref_entry) to
106 * describe a single cached reference. This data structure only
107 * occurs embedded in a union in struct ref_entry, and only when
108 * (ref_entry->flag & REF_DIR) is zero.
109 */
593f1bb8 110struct ref_value {
6c6f58df
MH
111 /*
112 * The name of the object to which this reference resolves
113 * (which may be a tag object). If REF_ISBROKEN, this is
114 * null. If REF_ISSYMREF, then this is the name of the object
115 * referred to by the last reference in the symlink chain.
116 */
593f1bb8 117 unsigned char sha1[20];
6c6f58df
MH
118
119 /*
120 * If REF_KNOWS_PEELED, then this field holds the peeled value
121 * of this reference, or null if the reference is known not to
122 * be peelable.
123 */
593f1bb8
MH
124 unsigned char peeled[20];
125};
126
f006c42a
MH
127struct ref_cache;
128
28e6a34e
MH
129/*
130 * Information used (along with the information in ref_entry) to
131 * describe a level in the hierarchy of references. This data
132 * structure only occurs embedded in a union in struct ref_entry, and
133 * only when (ref_entry.flag & REF_DIR) is set. In that case,
134 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
135 * in the directory have already been read:
136 *
137 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
138 * or packed references, already read.
139 *
140 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
141 * references that hasn't been read yet (nor has any of its
142 * subdirectories).
143 *
144 * Entries within a directory are stored within a growable array of
145 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
146 * sorted are sorted by their component name in strcmp() order and the
147 * remaining entries are unsorted.
148 *
149 * Loose references are read lazily, one directory at a time. When a
150 * directory of loose references is read, then all of the references
151 * in that directory are stored, and REF_INCOMPLETE stubs are created
152 * for any subdirectories, but the subdirectories themselves are not
153 * read. The reading is triggered by get_ref_dir().
154 */
d3177275 155struct ref_dir {
e9c4c111 156 int nr, alloc;
e6ed3ca6
MH
157
158 /*
159 * Entries with index 0 <= i < sorted are sorted by name. New
160 * entries are appended to the list unsorted, and are sorted
161 * only when required; thus we avoid the need to sort the list
162 * after the addition of every reference.
163 */
164 int sorted;
165
f006c42a
MH
166 /* A pointer to the ref_cache that contains this ref_dir. */
167 struct ref_cache *ref_cache;
168
d3177275 169 struct ref_entry **entries;
e9c4c111
JP
170};
171
89df9c84
MH
172/*
173 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01,
174 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see
175 * refs.h.
176 */
177
178/*
179 * The field ref_entry->u.value.peeled of this value entry contains
180 * the correct peeled value for the reference, which might be
181 * null_sha1 if the reference is not a tag or if it is broken.
182 */
432ad41e 183#define REF_KNOWS_PEELED 0x08
28e6a34e
MH
184
185/* ref_entry represents a directory of references */
432ad41e 186#define REF_DIR 0x10
cf0adba7 187
28e6a34e
MH
188/*
189 * Entry has not yet been read from disk (used only for REF_DIR
190 * entries representing loose references)
191 */
192#define REF_INCOMPLETE 0x20
193
432ad41e
MH
194/*
195 * A ref_entry represents either a reference or a "subdirectory" of
28e6a34e
MH
196 * references.
197 *
198 * Each directory in the reference namespace is represented by a
199 * ref_entry with (flags & REF_DIR) set and containing a subdir member
200 * that holds the entries in that directory that have been read so
201 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
202 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
203 * used for loose reference directories.
204 *
205 * References are represented by a ref_entry with (flags & REF_DIR)
206 * unset and a value member that describes the reference's value. The
207 * flag member is at the ref_entry level, but it is also needed to
208 * interpret the contents of the value field (in other words, a
209 * ref_value object is not very much use without the enclosing
210 * ref_entry).
432ad41e
MH
211 *
212 * Reference names cannot end with slash and directories' names are
213 * always stored with a trailing slash (except for the top-level
214 * directory, which is always denoted by ""). This has two nice
215 * consequences: (1) when the entries in each subdir are sorted
216 * lexicographically by name (as they usually are), the references in
217 * a whole tree can be generated in lexicographic order by traversing
218 * the tree in left-to-right, depth-first order; (2) the names of
219 * references and subdirectories cannot conflict, and therefore the
220 * presence of an empty subdirectory does not block the creation of a
221 * similarly-named reference. (The fact that reference names with the
222 * same leading components can conflict *with each other* is a
223 * separate issue that is regulated by is_refname_available().)
224 *
225 * Please note that the name field contains the fully-qualified
226 * reference (or subdirectory) name. Space could be saved by only
227 * storing the relative names. But that would require the full names
228 * to be generated on the fly when iterating in do_for_each_ref(), and
229 * would break callback functions, who have always been able to assume
230 * that the name strings that they are passed will not be freed during
231 * the iteration.
232 */
bc5fd6d3
MH
233struct ref_entry {
234 unsigned char flag; /* ISSYMREF? ISPACKED? */
593f1bb8 235 union {
432ad41e
MH
236 struct ref_value value; /* if not (flags&REF_DIR) */
237 struct ref_dir subdir; /* if (flags&REF_DIR) */
593f1bb8 238 } u;
432ad41e
MH
239 /*
240 * The full name of the reference (e.g., "refs/heads/master")
241 * or the full name of the directory with a trailing slash
242 * (e.g., "refs/heads/"):
243 */
bc5fd6d3
MH
244 char name[FLEX_ARRAY];
245};
e1e22e37 246
28e6a34e
MH
247static void read_loose_refs(const char *dirname, struct ref_dir *dir);
248
d7826d54
MH
249static struct ref_dir *get_ref_dir(struct ref_entry *entry)
250{
28e6a34e 251 struct ref_dir *dir;
d7826d54 252 assert(entry->flag & REF_DIR);
28e6a34e
MH
253 dir = &entry->u.subdir;
254 if (entry->flag & REF_INCOMPLETE) {
255 read_loose_refs(entry->name, dir);
256 entry->flag &= ~REF_INCOMPLETE;
257 }
258 return dir;
d7826d54
MH
259}
260
cddc4258
MH
261static struct ref_entry *create_ref_entry(const char *refname,
262 const unsigned char *sha1, int flag,
263 int check_name)
e1e22e37
LT
264{
265 int len;
cddc4258 266 struct ref_entry *ref;
e1e22e37 267
09116a1c 268 if (check_name &&
dfefa935
MH
269 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
270 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
271 len = strlen(refname) + 1;
272 ref = xmalloc(sizeof(struct ref_entry) + len);
593f1bb8
MH
273 hashcpy(ref->u.value.sha1, sha1);
274 hashclr(ref->u.value.peeled);
cddc4258
MH
275 memcpy(ref->name, refname, len);
276 ref->flag = flag;
277 return ref;
278}
279
432ad41e
MH
280static void clear_ref_dir(struct ref_dir *dir);
281
732134ed
MH
282static void free_ref_entry(struct ref_entry *entry)
283{
27b5587c
MH
284 if (entry->flag & REF_DIR) {
285 /*
286 * Do not use get_ref_dir() here, as that might
287 * trigger the reading of loose refs.
288 */
289 clear_ref_dir(&entry->u.subdir);
290 }
732134ed
MH
291 free(entry);
292}
293
432ad41e
MH
294/*
295 * Add a ref_entry to the end of dir (unsorted). Entry is always
296 * stored directly in dir; no recursion into subdirectories is
297 * done.
298 */
299static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
cddc4258 300{
432ad41e
MH
301 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
302 dir->entries[dir->nr++] = entry;
654ad400
MH
303 /* optimize for the case that entries are added in order */
304 if (dir->nr == 1 ||
305 (dir->nr == dir->sorted + 1 &&
306 strcmp(dir->entries[dir->nr - 2]->name,
307 dir->entries[dir->nr - 1]->name) < 0))
308 dir->sorted = dir->nr;
c774aab9
JP
309}
310
432ad41e
MH
311/*
312 * Clear and free all entries in dir, recursively.
313 */
d3177275 314static void clear_ref_dir(struct ref_dir *dir)
bc5fd6d3
MH
315{
316 int i;
d3177275
MH
317 for (i = 0; i < dir->nr; i++)
318 free_ref_entry(dir->entries[i]);
319 free(dir->entries);
320 dir->sorted = dir->nr = dir->alloc = 0;
321 dir->entries = NULL;
bc5fd6d3
MH
322}
323
432ad41e
MH
324/*
325 * Create a struct ref_entry object for the specified dirname.
326 * dirname is the name of the directory with a trailing slash (e.g.,
327 * "refs/heads/") or "" for the top-level directory.
328 */
f006c42a 329static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
b9146f51
RS
330 const char *dirname, size_t len,
331 int incomplete)
432ad41e
MH
332{
333 struct ref_entry *direntry;
432ad41e 334 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
b9146f51
RS
335 memcpy(direntry->name, dirname, len);
336 direntry->name[len] = '\0';
f006c42a 337 direntry->u.subdir.ref_cache = ref_cache;
28e6a34e 338 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
432ad41e
MH
339 return direntry;
340}
341
e9c4c111 342static int ref_entry_cmp(const void *a, const void *b)
c774aab9 343{
e9c4c111
JP
344 struct ref_entry *one = *(struct ref_entry **)a;
345 struct ref_entry *two = *(struct ref_entry **)b;
346 return strcmp(one->name, two->name);
347}
c774aab9 348
d3177275 349static void sort_ref_dir(struct ref_dir *dir);
bc5fd6d3 350
e1980c9d
JH
351struct string_slice {
352 size_t len;
353 const char *str;
354};
355
356static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
357{
358 struct string_slice *key = (struct string_slice *)key_;
359 struct ref_entry *ent = *(struct ref_entry **)ent_;
360 int entlen = strlen(ent->name);
361 int cmplen = key->len < entlen ? key->len : entlen;
362 int cmp = memcmp(key->str, ent->name, cmplen);
363 if (cmp)
364 return cmp;
365 return key->len - entlen;
366}
367
432ad41e
MH
368/*
369 * Return the entry with the given refname from the ref_dir
370 * (non-recursively), sorting dir if necessary. Return NULL if no
28e6a34e 371 * such entry is found. dir must already be complete.
432ad41e 372 */
40ad937d
RS
373static struct ref_entry *search_ref_dir(struct ref_dir *dir,
374 const char *refname, size_t len)
bc5fd6d3 375{
e1980c9d
JH
376 struct ref_entry **r;
377 struct string_slice key;
bc5fd6d3 378
432ad41e 379 if (refname == NULL || !dir->nr)
bc5fd6d3
MH
380 return NULL;
381
d3177275 382 sort_ref_dir(dir);
e1980c9d
JH
383 key.len = len;
384 key.str = refname;
385 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
386 ref_entry_cmp_sslice);
bc5fd6d3
MH
387
388 if (r == NULL)
389 return NULL;
390
391 return *r;
392}
393
f348ac92
MH
394/*
395 * Search for a directory entry directly within dir (without
396 * recursing). Sort dir if necessary. subdirname must be a directory
397 * name (i.e., end in '/'). If mkdir is set, then create the
398 * directory if it is missing; otherwise, return NULL if the desired
28e6a34e 399 * directory cannot be found. dir must already be complete.
f348ac92 400 */
3f3aa1bc 401static struct ref_dir *search_for_subdir(struct ref_dir *dir,
dd02e728
RS
402 const char *subdirname, size_t len,
403 int mkdir)
f348ac92 404{
40ad937d 405 struct ref_entry *entry = search_ref_dir(dir, subdirname, len);
f348ac92
MH
406 if (!entry) {
407 if (!mkdir)
408 return NULL;
28e6a34e
MH
409 /*
410 * Since dir is complete, the absence of a subdir
411 * means that the subdir really doesn't exist;
412 * therefore, create an empty record for it but mark
413 * the record complete.
414 */
b9146f51 415 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
f348ac92
MH
416 add_entry_to_dir(dir, entry);
417 }
3f3aa1bc 418 return get_ref_dir(entry);
f348ac92
MH
419}
420
432ad41e
MH
421/*
422 * If refname is a reference name, find the ref_dir within the dir
423 * tree that should hold refname. If refname is a directory name
424 * (i.e., ends in '/'), then return that ref_dir itself. dir must
28e6a34e
MH
425 * represent the top-level directory and must already be complete.
426 * Sort ref_dirs and recurse into subdirectories as necessary. If
427 * mkdir is set, then create any missing directories; otherwise,
428 * return NULL if the desired directory cannot be found.
432ad41e
MH
429 */
430static struct ref_dir *find_containing_dir(struct ref_dir *dir,
431 const char *refname, int mkdir)
432{
5fa04418 433 const char *slash;
5fa04418 434 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
dd02e728 435 size_t dirnamelen = slash - refname + 1;
3f3aa1bc 436 struct ref_dir *subdir;
dd02e728 437 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
663c1295
JH
438 if (!subdir) {
439 dir = NULL;
f348ac92 440 break;
432ad41e 441 }
3f3aa1bc 442 dir = subdir;
432ad41e
MH
443 }
444
432ad41e
MH
445 return dir;
446}
447
448/*
449 * Find the value entry with the given name in dir, sorting ref_dirs
450 * and recursing into subdirectories as necessary. If the name is not
451 * found or it corresponds to a directory entry, return NULL.
452 */
453static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
454{
455 struct ref_entry *entry;
456 dir = find_containing_dir(dir, refname, 0);
457 if (!dir)
458 return NULL;
40ad937d 459 entry = search_ref_dir(dir, refname, strlen(refname));
432ad41e
MH
460 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
461}
462
463/*
464 * Add a ref_entry to the ref_dir (unsorted), recursing into
465 * subdirectories as necessary. dir must represent the top-level
466 * directory. Return 0 on success.
467 */
468static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
469{
470 dir = find_containing_dir(dir, ref->name, 1);
471 if (!dir)
472 return -1;
473 add_entry_to_dir(dir, ref);
474 return 0;
475}
476
202a56a9
MH
477/*
478 * Emit a warning and return true iff ref1 and ref2 have the same name
479 * and the same sha1. Die if they have the same name but different
480 * sha1s.
481 */
482static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
483{
432ad41e 484 if (strcmp(ref1->name, ref2->name))
202a56a9 485 return 0;
432ad41e
MH
486
487 /* Duplicate name; make sure that they don't conflict: */
488
489 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
490 /* This is impossible by construction */
491 die("Reference directory conflict: %s", ref1->name);
492
493 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
494 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
495
496 warning("Duplicated ref: %s", ref1->name);
497 return 1;
202a56a9
MH
498}
499
e6ed3ca6 500/*
432ad41e
MH
501 * Sort the entries in dir non-recursively (if they are not already
502 * sorted) and remove any duplicate entries.
e6ed3ca6 503 */
d3177275 504static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 505{
202a56a9 506 int i, j;
81a79d8e 507 struct ref_entry *last = NULL;
c774aab9 508
e6ed3ca6
MH
509 /*
510 * This check also prevents passing a zero-length array to qsort(),
511 * which is a problem on some platforms.
512 */
d3177275 513 if (dir->sorted == dir->nr)
e9c4c111 514 return;
c774aab9 515
d3177275 516 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 517
81a79d8e
MH
518 /* Remove any duplicates: */
519 for (i = 0, j = 0; j < dir->nr; j++) {
520 struct ref_entry *entry = dir->entries[j];
521 if (last && is_dup_ref(last, entry))
522 free_ref_entry(entry);
523 else
524 last = dir->entries[i++] = entry;
e9c4c111 525 }
81a79d8e 526 dir->sorted = dir->nr = i;
e9c4c111 527}
c774aab9 528
fcce1703
MH
529/* Include broken references in a do_for_each_ref*() iteration: */
530#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
c774aab9 531
bc5fd6d3 532static struct ref_entry *current_ref;
c774aab9 533
fcce1703
MH
534/*
535 * Handle one reference in a do_for_each_ref*()-style iteration.
536 */
bc5fd6d3
MH
537static int do_one_ref(const char *base, each_ref_fn fn, int trim,
538 int flags, void *cb_data, struct ref_entry *entry)
539{
429213e4 540 int retval;
bc5fd6d3
MH
541 if (prefixcmp(entry->name, base))
542 return 0;
c774aab9 543
bc5fd6d3
MH
544 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
545 if (entry->flag & REF_ISBROKEN)
546 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 547 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
548 error("%s does not point to a valid object!", entry->name);
549 return 0;
550 }
551 }
552 current_ref = entry;
593f1bb8 553 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
554 current_ref = NULL;
555 return retval;
bc5fd6d3 556}
c774aab9 557
c36b5bc2 558/*
d3177275 559 * Call fn for each reference in dir that has index in the range
432ad41e
MH
560 * offset <= index < dir->nr. Recurse into subdirectories that are in
561 * that index range, sorting them before iterating. This function
562 * does not sort dir itself; it should be sorted beforehand.
c36b5bc2 563 */
d3177275
MH
564static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
565 const char *base,
566 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
567{
568 int i;
d3177275
MH
569 assert(dir->sorted == dir->nr);
570 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
571 struct ref_entry *entry = dir->entries[i];
572 int retval;
573 if (entry->flag & REF_DIR) {
d7826d54
MH
574 struct ref_dir *subdir = get_ref_dir(entry);
575 sort_ref_dir(subdir);
576 retval = do_for_each_ref_in_dir(subdir, 0,
432ad41e
MH
577 base, fn, trim, flags, cb_data);
578 } else {
579 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
580 }
c36b5bc2
MH
581 if (retval)
582 return retval;
583 }
584 return 0;
585}
586
b3fd060f 587/*
d3177275 588 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
589 * by refname. Recurse into subdirectories. If a value entry appears
590 * in both dir1 and dir2, then only process the version that is in
591 * dir2. The input dirs must already be sorted, but subdirs will be
592 * sorted as needed.
b3fd060f 593 */
d3177275
MH
594static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
595 struct ref_dir *dir2,
596 const char *base, each_ref_fn fn, int trim,
597 int flags, void *cb_data)
b3fd060f
MH
598{
599 int retval;
600 int i1 = 0, i2 = 0;
601
d3177275
MH
602 assert(dir1->sorted == dir1->nr);
603 assert(dir2->sorted == dir2->nr);
432ad41e
MH
604 while (1) {
605 struct ref_entry *e1, *e2;
606 int cmp;
607 if (i1 == dir1->nr) {
608 return do_for_each_ref_in_dir(dir2, i2,
609 base, fn, trim, flags, cb_data);
610 }
611 if (i2 == dir2->nr) {
612 return do_for_each_ref_in_dir(dir1, i1,
613 base, fn, trim, flags, cb_data);
614 }
615 e1 = dir1->entries[i1];
616 e2 = dir2->entries[i2];
617 cmp = strcmp(e1->name, e2->name);
618 if (cmp == 0) {
619 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
620 /* Both are directories; descend them in parallel. */
d7826d54
MH
621 struct ref_dir *subdir1 = get_ref_dir(e1);
622 struct ref_dir *subdir2 = get_ref_dir(e2);
623 sort_ref_dir(subdir1);
624 sort_ref_dir(subdir2);
432ad41e 625 retval = do_for_each_ref_in_dirs(
d7826d54 626 subdir1, subdir2,
432ad41e
MH
627 base, fn, trim, flags, cb_data);
628 i1++;
629 i2++;
630 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
631 /* Both are references; ignore the one from dir1. */
632 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
633 i1++;
634 i2++;
635 } else {
636 die("conflict between reference and directory: %s",
637 e1->name);
638 }
b3fd060f 639 } else {
432ad41e
MH
640 struct ref_entry *e;
641 if (cmp < 0) {
642 e = e1;
b3fd060f 643 i1++;
432ad41e
MH
644 } else {
645 e = e2;
646 i2++;
647 }
648 if (e->flag & REF_DIR) {
d7826d54
MH
649 struct ref_dir *subdir = get_ref_dir(e);
650 sort_ref_dir(subdir);
432ad41e 651 retval = do_for_each_ref_in_dir(
d7826d54 652 subdir, 0,
432ad41e
MH
653 base, fn, trim, flags, cb_data);
654 } else {
655 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
b3fd060f
MH
656 }
657 }
658 if (retval)
659 return retval;
660 }
d3177275
MH
661 if (i1 < dir1->nr)
662 return do_for_each_ref_in_dir(dir1, i1,
663 base, fn, trim, flags, cb_data);
664 if (i2 < dir2->nr)
665 return do_for_each_ref_in_dir(dir2, i2,
666 base, fn, trim, flags, cb_data);
b3fd060f
MH
667 return 0;
668}
669
d66da478
MH
670/*
671 * Return true iff refname1 and refname2 conflict with each other.
672 * Two reference names conflict if one of them exactly matches the
673 * leading components of the other; e.g., "foo/bar" conflicts with
674 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
675 * "foo/barbados".
676 */
677static int names_conflict(const char *refname1, const char *refname2)
678{
5a4d4947
MH
679 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
680 ;
681 return (*refname1 == '\0' && *refname2 == '/')
682 || (*refname1 == '/' && *refname2 == '\0');
683}
684
685struct name_conflict_cb {
686 const char *refname;
687 const char *oldrefname;
688 const char *conflicting_refname;
689};
690
691static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
692 int flags, void *cb_data)
693{
694 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
695 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
696 return 0;
697 if (names_conflict(data->refname, existingrefname)) {
698 data->conflicting_refname = existingrefname;
699 return 1;
d66da478 700 }
5a4d4947 701 return 0;
d66da478
MH
702}
703
bc5fd6d3
MH
704/*
705 * Return true iff a reference named refname could be created without
5a4d4947
MH
706 * conflicting with the name of an existing reference in array. If
707 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
708 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
709 * operation).
710 */
711static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 712 struct ref_dir *dir)
bc5fd6d3 713{
5a4d4947
MH
714 struct name_conflict_cb data;
715 data.refname = refname;
716 data.oldrefname = oldrefname;
717 data.conflicting_refname = NULL;
718
d3177275
MH
719 sort_ref_dir(dir);
720 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
721 0, DO_FOR_EACH_INCLUDE_BROKEN,
722 &data)) {
5a4d4947
MH
723 error("'%s' exists; cannot create '%s'",
724 data.conflicting_refname, refname);
725 return 0;
bc5fd6d3
MH
726 }
727 return 1;
e1e22e37
LT
728}
729
5e290ff7
JH
730/*
731 * Future: need to be in "struct repository"
732 * when doing a full libification.
733 */
79c7ca54
MH
734static struct ref_cache {
735 struct ref_cache *next;
d12229f5
MH
736 struct ref_entry *loose;
737 struct ref_entry *packed;
ce40979c
MH
738 /* The submodule name, or "" for the main repo. */
739 char name[FLEX_ARRAY];
79c7ca54 740} *ref_cache;
0e88c130 741
760c4512 742static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 743{
d12229f5
MH
744 if (refs->packed) {
745 free_ref_entry(refs->packed);
746 refs->packed = NULL;
747 }
5e290ff7 748}
e1e22e37 749
760c4512
MH
750static void clear_loose_ref_cache(struct ref_cache *refs)
751{
d12229f5
MH
752 if (refs->loose) {
753 free_ref_entry(refs->loose);
754 refs->loose = NULL;
755 }
760c4512
MH
756}
757
79c7ca54 758static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 759{
ce40979c 760 int len;
79c7ca54 761 struct ref_cache *refs;
ce40979c
MH
762 if (!submodule)
763 submodule = "";
764 len = strlen(submodule) + 1;
79c7ca54 765 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 766 memcpy(refs->name, submodule, len);
e5dbf605
MH
767 return refs;
768}
769
4349a668 770/*
79c7ca54 771 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
772 * the main repository, use submodule==NULL. The returned structure
773 * will be allocated and initialized but not necessarily populated; it
774 * should not be freed.
775 */
79c7ca54 776static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 777{
79c7ca54 778 struct ref_cache *refs = ref_cache;
0e88c130
MH
779 if (!submodule)
780 submodule = "";
781 while (refs) {
782 if (!strcmp(submodule, refs->name))
783 return refs;
784 refs = refs->next;
4349a668 785 }
0e88c130 786
79c7ca54
MH
787 refs = create_ref_cache(submodule);
788 refs->next = ref_cache;
789 ref_cache = refs;
0e88c130 790 return refs;
4349a668
MH
791}
792
8be8bde7 793void invalidate_ref_cache(const char *submodule)
f130b116 794{
c5f29abd
MH
795 struct ref_cache *refs = get_ref_cache(submodule);
796 clear_packed_ref_cache(refs);
797 clear_loose_ref_cache(refs);
5e290ff7 798}
e1e22e37 799
bc5fd6d3
MH
800/*
801 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
802 * Return a pointer to the refname within the line (null-terminated),
803 * or NULL if there was a problem.
804 */
805static const char *parse_ref_line(char *line, unsigned char *sha1)
806{
807 /*
808 * 42: the answer to everything.
809 *
810 * In this case, it happens to be the answer to
811 * 40 (length of sha1 hex representation)
812 * +1 (space in between hex and name)
813 * +1 (newline at the end of the line)
814 */
815 int len = strlen(line) - 42;
816
817 if (len <= 0)
818 return NULL;
819 if (get_sha1_hex(line, sha1) < 0)
820 return NULL;
821 if (!isspace(line[40]))
822 return NULL;
823 line += 41;
824 if (isspace(*line))
825 return NULL;
826 if (line[len] != '\n')
827 return NULL;
828 line[len] = 0;
829
830 return line;
831}
832
c29c46fa
MH
833/*
834 * Read f, which is a packed-refs file, into dir.
835 *
836 * A comment line of the form "# pack-refs with: " may contain zero or
837 * more traits. We interpret the traits as follows:
838 *
839 * No traits:
840 *
841 * Probably no references are peeled. But if the file contains a
842 * peeled value for a reference, we will use it.
843 *
844 * peeled:
845 *
846 * References under "refs/tags/", if they *can* be peeled, *are*
847 * peeled in this file. References outside of "refs/tags/" are
848 * probably not peeled even if they could have been, but if we find
849 * a peeled value for such a reference we will use it.
850 *
851 * fully-peeled:
852 *
853 * All references in the file that can be peeled are peeled.
854 * Inversely (and this is more important), any references in the
855 * file for which no peeled value is recorded is not peelable. This
856 * trait should typically be written alongside "peeled" for
857 * compatibility with older clients, but we do not require it
858 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
859 */
d3177275 860static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 861{
e9c4c111 862 struct ref_entry *last = NULL;
f4204ab9 863 char refline[PATH_MAX];
c29c46fa 864 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
f4204ab9
JH
865
866 while (fgets(refline, sizeof(refline), f)) {
867 unsigned char sha1[20];
dfefa935 868 const char *refname;
f4204ab9
JH
869 static const char header[] = "# pack-refs with:";
870
871 if (!strncmp(refline, header, sizeof(header)-1)) {
872 const char *traits = refline + sizeof(header) - 1;
c29c46fa
MH
873 if (strstr(traits, " fully-peeled "))
874 peeled = PEELED_FULLY;
875 else if (strstr(traits, " peeled "))
876 peeled = PEELED_TAGS;
f4204ab9
JH
877 /* perhaps other traits later as well */
878 continue;
879 }
880
dfefa935
MH
881 refname = parse_ref_line(refline, sha1);
882 if (refname) {
c29c46fa
MH
883 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
884 if (peeled == PEELED_FULLY ||
885 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
886 last->flag |= REF_KNOWS_PEELED;
d3177275 887 add_ref(dir, last);
f4204ab9
JH
888 continue;
889 }
890 if (last &&
891 refline[0] == '^' &&
892 strlen(refline) == 42 &&
893 refline[41] == '\n' &&
c29c46fa 894 !get_sha1_hex(refline + 1, sha1)) {
593f1bb8 895 hashcpy(last->u.value.peeled, sha1);
c29c46fa
MH
896 /*
897 * Regardless of what the file header said,
898 * we definitely know the value of *this*
899 * reference:
900 */
901 last->flag |= REF_KNOWS_PEELED;
902 }
f4204ab9 903 }
f4204ab9
JH
904}
905
d3177275 906static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 907{
d12229f5 908 if (!refs->packed) {
4349a668
MH
909 const char *packed_refs_file;
910 FILE *f;
0bad611b 911
b9146f51 912 refs->packed = create_dir_entry(refs, "", 0, 0);
316b097a
MH
913 if (*refs->name)
914 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
915 else
916 packed_refs_file = git_path("packed-refs");
917 f = fopen(packed_refs_file, "r");
e1e22e37 918 if (f) {
d7826d54 919 read_packed_refs(f, get_ref_dir(refs->packed));
e1e22e37 920 fclose(f);
e1e22e37 921 }
e1e22e37 922 }
d7826d54 923 return get_ref_dir(refs->packed);
e1e22e37
LT
924}
925
30249ee6
MH
926void add_packed_ref(const char *refname, const unsigned char *sha1)
927{
928 add_ref(get_packed_refs(get_ref_cache(NULL)),
929 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
930}
931
abc39098 932/*
28e6a34e
MH
933 * Read the loose references from the namespace dirname into dir
934 * (without recursing). dirname must end with '/'. dir must be the
935 * directory entry corresponding to dirname.
abc39098 936 */
423a1afc 937static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 938{
423a1afc 939 struct ref_cache *refs = dir->ref_cache;
d3177275 940 DIR *d;
0bad611b 941 const char *path;
d5fdae67 942 struct dirent *de;
abc39098 943 int dirnamelen = strlen(dirname);
72b64b44 944 struct strbuf refname;
0bad611b 945
3b124823 946 if (*refs->name)
66a3d20b 947 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 948 else
66a3d20b 949 path = git_path("%s", dirname);
0bad611b 950
d3177275 951 d = opendir(path);
d5fdae67
MH
952 if (!d)
953 return;
954
66a3d20b
MH
955 strbuf_init(&refname, dirnamelen + 257);
956 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
957
958 while ((de = readdir(d)) != NULL) {
959 unsigned char sha1[20];
960 struct stat st;
961 int flag;
d5fdae67
MH
962 const char *refdir;
963
964 if (de->d_name[0] == '.')
965 continue;
d5fdae67
MH
966 if (has_extension(de->d_name, ".lock"))
967 continue;
72b64b44 968 strbuf_addstr(&refname, de->d_name);
d5fdae67 969 refdir = *refs->name
72b64b44
MH
970 ? git_path_submodule(refs->name, "%s", refname.buf)
971 : git_path("%s", refname.buf);
972 if (stat(refdir, &st) < 0) {
973 ; /* silently ignore */
974 } else if (S_ISDIR(st.st_mode)) {
abc39098 975 strbuf_addch(&refname, '/');
28e6a34e 976 add_entry_to_dir(dir,
b9146f51
RS
977 create_dir_entry(refs, refname.buf,
978 refname.len, 1));
72b64b44 979 } else {
3b124823 980 if (*refs->name) {
f8948e2f 981 hashclr(sha1);
0bad611b 982 flag = 0;
72b64b44 983 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
0bad611b 984 hashclr(sha1);
98ac34b2 985 flag |= REF_ISBROKEN;
0bad611b 986 }
72b64b44 987 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
988 hashclr(sha1);
989 flag |= REF_ISBROKEN;
990 }
9f2fb4a3
MH
991 add_entry_to_dir(dir,
992 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 993 }
66a3d20b 994 strbuf_setlen(&refname, dirnamelen);
e1e22e37 995 }
72b64b44 996 strbuf_release(&refname);
d5fdae67 997 closedir(d);
e1e22e37
LT
998}
999
d3177275 1000static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 1001{
d12229f5 1002 if (!refs->loose) {
28e6a34e
MH
1003 /*
1004 * Mark the top-level directory complete because we
1005 * are about to read the only subdirectory that can
1006 * hold references:
1007 */
b9146f51 1008 refs->loose = create_dir_entry(refs, "", 0, 0);
28e6a34e
MH
1009 /*
1010 * Create an incomplete entry for "refs/":
1011 */
1012 add_entry_to_dir(get_ref_dir(refs->loose),
b9146f51 1013 create_dir_entry(refs, "refs/", 5, 1));
e1e22e37 1014 }
d7826d54 1015 return get_ref_dir(refs->loose);
e1e22e37
LT
1016}
1017
ca8db142
LT
1018/* We allow "recursive" symbolic refs. Only within reason, though */
1019#define MAXDEPTH 5
0ebde32c
LT
1020#define MAXREFLEN (1024)
1021
e5fa45c1
JH
1022/*
1023 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
1024 * from the loose refs in ref_cache refs. Find <refname> in the
1025 * packed-refs file for the submodule.
e5fa45c1 1026 */
b0626608 1027static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 1028 const char *refname, unsigned char *sha1)
0ebde32c 1029{
2c5c66be 1030 struct ref_entry *ref;
d3177275 1031 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 1032
432ad41e 1033 ref = find_ref(dir, refname);
b0626608
MH
1034 if (ref == NULL)
1035 return -1;
1036
593f1bb8 1037 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 1038 return 0;
0ebde32c
LT
1039}
1040
b0626608 1041static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 1042 const char *refname, unsigned char *sha1,
dfefa935 1043 int recursion)
0ebde32c 1044{
064d51dc 1045 int fd, len;
0ebde32c 1046 char buffer[128], *p;
064d51dc 1047 char *path;
0ebde32c 1048
064d51dc 1049 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 1050 return -1;
064d51dc
MH
1051 path = *refs->name
1052 ? git_path_submodule(refs->name, "%s", refname)
1053 : git_path("%s", refname);
1054 fd = open(path, O_RDONLY);
0ebde32c 1055 if (fd < 0)
b0626608 1056 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
1057
1058 len = read(fd, buffer, sizeof(buffer)-1);
1059 close(fd);
1060 if (len < 0)
1061 return -1;
1062 while (len && isspace(buffer[len-1]))
1063 len--;
1064 buffer[len] = 0;
1065
1066 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 1067 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
1068 return 0;
1069
1070 /* Symref? */
1071 if (strncmp(buffer, "ref:", 4))
1072 return -1;
1073 p = buffer + 4;
1074 while (isspace(*p))
1075 p++;
1076
064d51dc 1077 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
1078}
1079
85be1fe3 1080int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
1081{
1082 int len = strlen(path), retval;
064d51dc 1083 char *submodule;
b0626608 1084 struct ref_cache *refs;
0ebde32c
LT
1085
1086 while (len && path[len-1] == '/')
1087 len--;
1088 if (!len)
1089 return -1;
b0626608
MH
1090 submodule = xstrndup(path, len);
1091 refs = get_ref_cache(submodule);
1092 free(submodule);
1093
064d51dc 1094 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
1095 return retval;
1096}
ca8db142 1097
4886b89f 1098/*
c224ca7f
MH
1099 * Try to read ref from the packed references. On success, set sha1
1100 * and return 0; otherwise, return -1.
4886b89f 1101 */
dfefa935 1102static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 1103{
d3177275 1104 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 1105 struct ref_entry *entry = find_ref(packed, refname);
2c5c66be 1106 if (entry) {
593f1bb8 1107 hashcpy(sha1, entry->u.value.sha1);
2c5c66be 1108 return 0;
c224ca7f
MH
1109 }
1110 return -1;
1111}
1112
8d68493f 1113const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 1114{
0104ca09
HO
1115 int depth = MAXDEPTH;
1116 ssize_t len;
a876ed83 1117 char buffer[256];
dfefa935 1118 static char refname_buffer[256];
ca8db142 1119
8da19775
JH
1120 if (flag)
1121 *flag = 0;
1122
dfefa935 1123 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
1124 return NULL;
1125
a876ed83 1126 for (;;) {
55956350 1127 char path[PATH_MAX];
a876ed83
JH
1128 struct stat st;
1129 char *buf;
1130 int fd;
8a65ff76 1131
a876ed83
JH
1132 if (--depth < 0)
1133 return NULL;
ca8db142 1134
dfefa935 1135 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 1136
a876ed83 1137 if (lstat(path, &st) < 0) {
c224ca7f
MH
1138 if (errno != ENOENT)
1139 return NULL;
1140 /*
1141 * The loose reference file does not exist;
1142 * check for a packed reference.
1143 */
dfefa935 1144 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
1145 if (flag)
1146 *flag |= REF_ISPACKED;
dfefa935 1147 return refname;
434cd0cd 1148 }
c224ca7f
MH
1149 /* The reference is not a packed reference, either. */
1150 if (reading) {
a876ed83 1151 return NULL;
c224ca7f
MH
1152 } else {
1153 hashclr(sha1);
dfefa935 1154 return refname;
c224ca7f 1155 }
a876ed83 1156 }
ca8db142 1157
a876ed83
JH
1158 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1159 if (S_ISLNK(st.st_mode)) {
1160 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
1161 if (len < 0)
1162 return NULL;
b54cb795 1163 buffer[len] = 0;
1f58a038
MH
1164 if (!prefixcmp(buffer, "refs/") &&
1165 !check_refname_format(buffer, 0)) {
dfefa935
MH
1166 strcpy(refname_buffer, buffer);
1167 refname = refname_buffer;
8da19775
JH
1168 if (flag)
1169 *flag |= REF_ISSYMREF;
a876ed83
JH
1170 continue;
1171 }
ca8db142 1172 }
a876ed83 1173
7a21632f
DS
1174 /* Is it a directory? */
1175 if (S_ISDIR(st.st_mode)) {
1176 errno = EISDIR;
1177 return NULL;
1178 }
1179
a876ed83
JH
1180 /*
1181 * Anything else, just open it and try to use it as
1182 * a ref
1183 */
1184 fd = open(path, O_RDONLY);
1185 if (fd < 0)
1186 return NULL;
93d26e4c 1187 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1188 close(fd);
28775050
MH
1189 if (len < 0)
1190 return NULL;
1191 while (len && isspace(buffer[len-1]))
1192 len--;
1193 buffer[len] = '\0';
a876ed83
JH
1194
1195 /*
1196 * Is it a symbolic ref?
1197 */
28775050 1198 if (prefixcmp(buffer, "ref:"))
a876ed83 1199 break;
55956350
JH
1200 if (flag)
1201 *flag |= REF_ISSYMREF;
a876ed83 1202 buf = buffer + 4;
28775050
MH
1203 while (isspace(*buf))
1204 buf++;
313fb010 1205 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1206 if (flag)
1207 *flag |= REF_ISBROKEN;
313fb010
MH
1208 return NULL;
1209 }
dfefa935 1210 refname = strcpy(refname_buffer, buf);
8a65ff76 1211 }
f989fea0
MH
1212 /* Please note that FETCH_HEAD has a second line containing other data. */
1213 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1214 if (flag)
1215 *flag |= REF_ISBROKEN;
a876ed83 1216 return NULL;
629cd3ac 1217 }
dfefa935 1218 return refname;
a876ed83
JH
1219}
1220
96ec7b1e
NTND
1221char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1222{
8cad4744 1223 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1224 return ret ? xstrdup(ret) : NULL;
1225}
1226
d08bae7e
IL
1227/* The argument to filter_refs */
1228struct ref_filter {
1229 const char *pattern;
1230 each_ref_fn *fn;
1231 void *cb_data;
1232};
1233
dfefa935 1234int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1235{
8d68493f 1236 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1237 return 0;
1238 return -1;
8a65ff76
LT
1239}
1240
dfefa935 1241int read_ref(const char *refname, unsigned char *sha1)
c6893323 1242{
dfefa935 1243 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1244}
1245
bc5fd6d3 1246int ref_exists(const char *refname)
ef06b918 1247{
bc5fd6d3
MH
1248 unsigned char sha1[20];
1249 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1250}
1251
85be1fe3 1252static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1253 void *data)
d08bae7e
IL
1254{
1255 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1256 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1257 return 0;
85be1fe3 1258 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1259}
1260
dfefa935 1261int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1262{
1263 int flag;
1264 unsigned char base[20];
1265 struct object *o;
1266
dfefa935
MH
1267 if (current_ref && (current_ref->name == refname
1268 || !strcmp(current_ref->name, refname))) {
0ae91be0 1269 if (current_ref->flag & REF_KNOWS_PEELED) {
e6dbffa6
JK
1270 if (is_null_sha1(current_ref->u.value.peeled))
1271 return -1;
593f1bb8 1272 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
1273 return 0;
1274 }
593f1bb8 1275 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
1276 goto fallback;
1277 }
1278
dfefa935 1279 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1280 return -1;
1281
1282 if ((flag & REF_ISPACKED)) {
d3177275 1283 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
432ad41e 1284 struct ref_entry *r = find_ref(dir, refname);
cf0adba7 1285
e9c4c111 1286 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
593f1bb8 1287 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1288 return 0;
cf0adba7 1289 }
cf0adba7
JH
1290 }
1291
0ae91be0 1292fallback:
6c4a060d
JK
1293 o = lookup_unknown_object(base);
1294 if (o->type == OBJ_NONE) {
1295 int type = sha1_object_info(base, NULL);
1296 if (type < 0)
1297 return -1;
1298 o->type = type;
1299 }
1300
1301 if (o->type == OBJ_TAG) {
44da6f69 1302 o = deref_tag_noverify(o);
cf0adba7
JH
1303 if (o) {
1304 hashcpy(sha1, o->sha1);
1305 return 0;
1306 }
1307 }
1308 return -1;
1309}
1310
bc5fd6d3
MH
1311struct warn_if_dangling_data {
1312 FILE *fp;
1313 const char *refname;
1314 const char *msg_fmt;
1315};
1316
1317static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1318 int flags, void *cb_data)
1319{
1320 struct warn_if_dangling_data *d = cb_data;
1321 const char *resolves_to;
1322 unsigned char junk[20];
1323
1324 if (!(flags & REF_ISSYMREF))
1325 return 0;
1326
1327 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1328 if (!resolves_to || strcmp(resolves_to, d->refname))
1329 return 0;
1330
1331 fprintf(d->fp, d->msg_fmt, refname);
1be65eda 1332 fputc('\n', d->fp);
bc5fd6d3
MH
1333 return 0;
1334}
1335
1336void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1337{
1338 struct warn_if_dangling_data data;
1339
1340 data.fp = fp;
1341 data.refname = refname;
1342 data.msg_fmt = msg_fmt;
1343 for_each_rawref(warn_if_dangling_symref, &data);
1344}
1345
fcce1703
MH
1346/*
1347 * Call fn for each reference in the specified submodule for which the
1348 * refname begins with base. If trim is non-zero, then trim that many
1349 * characters off the beginning of each refname before passing the
1350 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include
1351 * broken references in the iteration. If fn ever returns a non-zero
1352 * value, stop the iteration and return that value; otherwise, return
1353 * 0.
1354 */
0bad611b
HV
1355static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1356 int trim, int flags, void *cb_data)
8a65ff76 1357{
316b097a 1358 struct ref_cache *refs = get_ref_cache(submodule);
933ac036
MH
1359 struct ref_dir *packed_dir = get_packed_refs(refs);
1360 struct ref_dir *loose_dir = get_loose_refs(refs);
1361 int retval = 0;
1362
1363 if (base && *base) {
1364 packed_dir = find_containing_dir(packed_dir, base, 0);
1365 loose_dir = find_containing_dir(loose_dir, base, 0);
1366 }
1367
1368 if (packed_dir && loose_dir) {
1369 sort_ref_dir(packed_dir);
1370 sort_ref_dir(loose_dir);
1371 retval = do_for_each_ref_in_dirs(
1372 packed_dir, loose_dir,
1373 base, fn, trim, flags, cb_data);
1374 } else if (packed_dir) {
1375 sort_ref_dir(packed_dir);
1376 retval = do_for_each_ref_in_dir(
1377 packed_dir, 0,
1378 base, fn, trim, flags, cb_data);
1379 } else if (loose_dir) {
1380 sort_ref_dir(loose_dir);
1381 retval = do_for_each_ref_in_dir(
1382 loose_dir, 0,
1383 base, fn, trim, flags, cb_data);
1384 }
1385
1386 return retval;
8a65ff76
LT
1387}
1388
0bad611b 1389static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1390{
1391 unsigned char sha1[20];
8da19775
JH
1392 int flag;
1393
0bad611b
HV
1394 if (submodule) {
1395 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1396 return fn("HEAD", sha1, 0, cb_data);
1397
1398 return 0;
1399 }
1400
c6893323 1401 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1402 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1403
2f34ba32 1404 return 0;
723c31fe
LT
1405}
1406
0bad611b
HV
1407int head_ref(each_ref_fn fn, void *cb_data)
1408{
1409 return do_head_ref(NULL, fn, cb_data);
1410}
1411
9ef6aeb0
HV
1412int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1413{
1414 return do_head_ref(submodule, fn, cb_data);
1415}
1416
cb5d709f 1417int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1418{
b3cfc406 1419 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1420}
1421
9ef6aeb0
HV
1422int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1423{
b3cfc406 1424 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1425}
1426
2a8177b6
CC
1427int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1428{
0bad611b 1429 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1430}
1431
9ef6aeb0
HV
1432int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1433 each_ref_fn fn, void *cb_data)
1434{
1435 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1436}
1437
cb5d709f 1438int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1439{
2a8177b6 1440 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1441}
1442
9ef6aeb0
HV
1443int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1444{
1445 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1446}
1447
cb5d709f 1448int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1449{
2a8177b6 1450 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1451}
1452
9ef6aeb0
HV
1453int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1454{
1455 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1456}
1457
cb5d709f 1458int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1459{
2a8177b6 1460 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1461}
1462
9ef6aeb0
HV
1463int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1464{
1465 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1466}
1467
29268700
CC
1468int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1469{
0bad611b 1470 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1471}
1472
a1bea2c1
JT
1473int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1474{
1475 struct strbuf buf = STRBUF_INIT;
1476 int ret = 0;
1477 unsigned char sha1[20];
1478 int flag;
1479
1480 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1481 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1482 ret = fn(buf.buf, sha1, flag, cb_data);
1483 strbuf_release(&buf);
1484
1485 return ret;
1486}
1487
1488int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1489{
1490 struct strbuf buf = STRBUF_INIT;
1491 int ret;
1492 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1493 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1494 strbuf_release(&buf);
1495 return ret;
1496}
1497
b09fe971
IL
1498int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1499 const char *prefix, void *cb_data)
d08bae7e
IL
1500{
1501 struct strbuf real_pattern = STRBUF_INIT;
1502 struct ref_filter filter;
d08bae7e
IL
1503 int ret;
1504
b09fe971 1505 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1506 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1507 else if (prefix)
1508 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1509 strbuf_addstr(&real_pattern, pattern);
1510
894a9d33 1511 if (!has_glob_specials(pattern)) {
9517e6b8 1512 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1513 if (real_pattern.buf[real_pattern.len - 1] != '/')
1514 strbuf_addch(&real_pattern, '/');
1515 /* No need to check for '*', there is none. */
1516 strbuf_addch(&real_pattern, '*');
1517 }
1518
1519 filter.pattern = real_pattern.buf;
1520 filter.fn = fn;
1521 filter.cb_data = cb_data;
1522 ret = for_each_ref(filter_refs, &filter);
1523
1524 strbuf_release(&real_pattern);
1525 return ret;
1526}
1527
b09fe971
IL
1528int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1529{
1530 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1531}
1532
f8948e2f
JH
1533int for_each_rawref(each_ref_fn fn, void *cb_data)
1534{
b3cfc406 1535 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1536 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1537}
1538
4577e483 1539const char *prettify_refname(const char *name)
a9c37a72 1540{
a9c37a72
DB
1541 return name + (
1542 !prefixcmp(name, "refs/heads/") ? 11 :
1543 !prefixcmp(name, "refs/tags/") ? 10 :
1544 !prefixcmp(name, "refs/remotes/") ? 13 :
1545 0);
1546}
1547
79803322
SP
1548const char *ref_rev_parse_rules[] = {
1549 "%.*s",
1550 "refs/%.*s",
1551 "refs/tags/%.*s",
1552 "refs/heads/%.*s",
1553 "refs/remotes/%.*s",
1554 "refs/remotes/%.*s/HEAD",
1555 NULL
1556};
1557
1558int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1559{
1560 const char **p;
1561 const int abbrev_name_len = strlen(abbrev_name);
1562
1563 for (p = rules; *p; p++) {
1564 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1565 return 1;
1566 }
1567 }
1568
1569 return 0;
1570}
1571
e5f38ec3 1572static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1573 const unsigned char *old_sha1, int mustexist)
1574{
c6893323 1575 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1576 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1577 unlock_ref(lock);
1578 return NULL;
1579 }
a89fccd2 1580 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1581 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1582 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1583 unlock_ref(lock);
1584 return NULL;
1585 }
1586 return lock;
1587}
1588
7155b727 1589static int remove_empty_directories(const char *file)
bc7127ef
JH
1590{
1591 /* we want to create a file but there is a directory there;
1592 * if that is an empty directory (or a directory that contains
1593 * only empty directories), remove them.
1594 */
7155b727
JS
1595 struct strbuf path;
1596 int result;
bc7127ef 1597
7155b727
JS
1598 strbuf_init(&path, 20);
1599 strbuf_addstr(&path, file);
1600
a0f4afbe 1601 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1602
1603 strbuf_release(&path);
1604
1605 return result;
bc7127ef
JH
1606}
1607
ff74f7f1
JH
1608/*
1609 * *string and *len will only be substituted, and *string returned (for
1610 * later free()ing) if the string passed in is a magic short-hand form
1611 * to name a branch.
1612 */
1613static char *substitute_branch_name(const char **string, int *len)
1614{
1615 struct strbuf buf = STRBUF_INIT;
1616 int ret = interpret_branch_name(*string, &buf);
1617
1618 if (ret == *len) {
1619 size_t size;
1620 *string = strbuf_detach(&buf, &size);
1621 *len = size;
1622 return (char *)*string;
1623 }
1624
1625 return NULL;
1626}
1627
1628int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1629{
1630 char *last_branch = substitute_branch_name(&str, &len);
1631 const char **p, *r;
1632 int refs_found = 0;
1633
1634 *ref = NULL;
1635 for (p = ref_rev_parse_rules; *p; p++) {
1636 char fullref[PATH_MAX];
1637 unsigned char sha1_from_ref[20];
1638 unsigned char *this_result;
1639 int flag;
1640
1641 this_result = refs_found ? sha1_from_ref : sha1;
1642 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1643 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1644 if (r) {
1645 if (!refs_found++)
1646 *ref = xstrdup(r);
1647 if (!warn_ambiguous_refs)
1648 break;
55956350 1649 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1650 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1651 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1652 warning("ignoring broken ref %s.", fullref);
1653 }
ff74f7f1
JH
1654 }
1655 free(last_branch);
1656 return refs_found;
1657}
1658
1659int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1660{
1661 char *last_branch = substitute_branch_name(&str, &len);
1662 const char **p;
1663 int logs_found = 0;
1664
1665 *log = NULL;
1666 for (p = ref_rev_parse_rules; *p; p++) {
1667 struct stat st;
1668 unsigned char hash[20];
1669 char path[PATH_MAX];
1670 const char *ref, *it;
1671
1672 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1673 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1674 if (!ref)
1675 continue;
1676 if (!stat(git_path("logs/%s", path), &st) &&
1677 S_ISREG(st.st_mode))
1678 it = path;
1679 else if (strcmp(ref, path) &&
1680 !stat(git_path("logs/%s", ref), &st) &&
1681 S_ISREG(st.st_mode))
1682 it = ref;
1683 else
1684 continue;
1685 if (!logs_found++) {
1686 *log = xstrdup(it);
1687 hashcpy(sha1, hash);
1688 }
1689 if (!warn_ambiguous_refs)
1690 break;
1691 }
1692 free(last_branch);
1693 return logs_found;
1694}
1695
dfefa935
MH
1696static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1697 const unsigned char *old_sha1,
1698 int flags, int *type_p)
4bd18c43 1699{
434cd0cd 1700 char *ref_file;
dfefa935 1701 const char *orig_refname = refname;
4bd18c43 1702 struct ref_lock *lock;
5cc3cef9 1703 int last_errno = 0;
acd3b9ec 1704 int type, lflags;
4431fcc4 1705 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1706 int missing = 0;
4bd18c43
SP
1707
1708 lock = xcalloc(1, sizeof(struct ref_lock));
1709 lock->lock_fd = -1;
1710
8d68493f 1711 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1712 if (!refname && errno == EISDIR) {
bc7127ef
JH
1713 /* we are trying to lock foo but we used to
1714 * have foo/bar which now does not exist;
1715 * it is normal for the empty directory 'foo'
1716 * to remain.
1717 */
dfefa935 1718 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1719 if (remove_empty_directories(ref_file)) {
1720 last_errno = errno;
dfefa935 1721 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1722 goto error_return;
1723 }
8d68493f 1724 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1725 }
68db31cc
SV
1726 if (type_p)
1727 *type_p = type;
dfefa935 1728 if (!refname) {
5cc3cef9 1729 last_errno = errno;
818f477c 1730 error("unable to resolve reference %s: %s",
dfefa935 1731 orig_refname, strerror(errno));
5cc3cef9 1732 goto error_return;
4bd18c43 1733 }
5bdd8d4a 1734 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1735 /* When the ref did not exist and we are creating it,
1736 * make sure there is no existing ref that is packed
1737 * whose name begins with our refname, nor a ref whose
1738 * name is a proper prefix of our refname.
1739 */
5bdd8d4a 1740 if (missing &&
316b097a 1741 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1742 last_errno = ENOTDIR;
c976d415 1743 goto error_return;
f475e08e 1744 }
22a3844e 1745
c33d5174 1746 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1747
acd3b9ec
JH
1748 lflags = LOCK_DIE_ON_ERROR;
1749 if (flags & REF_NODEREF) {
dfefa935 1750 refname = orig_refname;
acd3b9ec
JH
1751 lflags |= LOCK_NODEREF;
1752 }
dfefa935
MH
1753 lock->ref_name = xstrdup(refname);
1754 lock->orig_ref_name = xstrdup(orig_refname);
1755 ref_file = git_path("%s", refname);
5bdd8d4a 1756 if (missing)
68db31cc
SV
1757 lock->force_write = 1;
1758 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1759 lock->force_write = 1;
4bd18c43 1760
5cc3cef9
JH
1761 if (safe_create_leading_directories(ref_file)) {
1762 last_errno = errno;
1763 error("unable to create directory for %s", ref_file);
1764 goto error_return;
1765 }
4bd18c43 1766
acd3b9ec 1767 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1768 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1769
1770 error_return:
1771 unlock_ref(lock);
1772 errno = last_errno;
1773 return NULL;
4bd18c43
SP
1774}
1775
dfefa935 1776struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1777{
53cce84c 1778 char refpath[PATH_MAX];
dfefa935 1779 if (check_refname_format(refname, 0))
4bd18c43 1780 return NULL;
dfefa935 1781 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1782 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1783}
1784
dfefa935
MH
1785struct ref_lock *lock_any_ref_for_update(const char *refname,
1786 const unsigned char *old_sha1, int flags)
4bd18c43 1787{
dfefa935 1788 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1789 return NULL;
dfefa935 1790 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1791}
1792
d66da478
MH
1793struct repack_without_ref_sb {
1794 const char *refname;
1795 int fd;
1796};
1797
1798static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1799 int flags, void *cb_data)
1800{
1801 struct repack_without_ref_sb *data = cb_data;
1802 char line[PATH_MAX + 100];
1803 int len;
1804
1805 if (!strcmp(data->refname, refname))
1806 return 0;
1807 len = snprintf(line, sizeof(line), "%s %s\n",
1808 sha1_to_hex(sha1), refname);
1809 /* this should not happen but just being defensive */
1810 if (len > sizeof(line))
1811 die("too long a refname '%s'", refname);
1812 write_or_die(data->fd, line, len);
1813 return 0;
1814}
1815
26a063a1
JH
1816static struct lock_file packlock;
1817
c0277d15
JH
1818static int repack_without_ref(const char *refname)
1819{
d66da478 1820 struct repack_without_ref_sb data;
b3f1280e
JK
1821 struct ref_cache *refs = get_ref_cache(NULL);
1822 struct ref_dir *packed = get_packed_refs(refs);
432ad41e 1823 if (find_ref(packed, refname) == NULL)
c0277d15 1824 return 0;
d66da478
MH
1825 data.refname = refname;
1826 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1827 if (data.fd < 0) {
1b018fd9 1828 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1829 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1830 }
b3f1280e
JK
1831 clear_packed_ref_cache(refs);
1832 packed = get_packed_refs(refs);
d3177275 1833 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1834 return commit_lock_file(&packlock);
1835}
1836
eca35a25 1837int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1838{
1839 struct ref_lock *lock;
eca35a25 1840 int err, i = 0, ret = 0, flag = 0;
c0277d15 1841
547d058f 1842 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
c0277d15
JH
1843 if (!lock)
1844 return 1;
045a476f 1845 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1846 /* loose */
547d058f
RS
1847 i = strlen(lock->lk->filename) - 5; /* .lock */
1848 lock->lk->filename[i] = 0;
1849 err = unlink_or_warn(lock->lk->filename);
691f1a28 1850 if (err && errno != ENOENT)
c0277d15 1851 ret = 1;
691f1a28 1852
547d058f 1853 lock->lk->filename[i] = '.';
c0277d15
JH
1854 }
1855 /* removing the loose one could have resurrected an earlier
1856 * packed one. Also, if it was not loose we need to repack
1857 * without it.
1858 */
b274a714 1859 ret |= repack_without_ref(lock->ref_name);
c0277d15 1860
691f1a28 1861 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1862 invalidate_ref_cache(NULL);
c0277d15
JH
1863 unlock_ref(lock);
1864 return ret;
4bd18c43
SP
1865}
1866
765c2258
PH
1867/*
1868 * People using contrib's git-new-workdir have .git/logs/refs ->
1869 * /some/other/path/.git/logs/refs, and that may live on another device.
1870 *
1871 * IOW, to avoid cross device rename errors, the temporary renamed log must
1872 * live into logs/refs.
1873 */
1874#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1875
dfefa935 1876int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1877{
c976d415
LH
1878 unsigned char sha1[20], orig_sha1[20];
1879 int flag = 0, logmoved = 0;
1880 struct ref_lock *lock;
c976d415 1881 struct stat loginfo;
dfefa935 1882 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1883 const char *symref = NULL;
316b097a 1884 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1885
450d4c0f 1886 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1887 return error("reflog for %s is a symlink", oldrefname);
c976d415 1888
8d68493f 1889 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1890 if (flag & REF_ISSYMREF)
fa58186c 1891 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1892 oldrefname);
eca35a25 1893 if (!symref)
dfefa935 1894 return error("refname %s not found", oldrefname);
c976d415 1895
316b097a 1896 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1897 return 1;
1898
316b097a 1899 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1900 return 1;
1901
dfefa935 1902 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1903 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1904 oldrefname, strerror(errno));
c976d415 1905
dfefa935
MH
1906 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1907 error("unable to delete old %s", oldrefname);
c976d415
LH
1908 goto rollback;
1909 }
1910
dfefa935
MH
1911 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1912 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1913 if (errno==EISDIR) {
dfefa935
MH
1914 if (remove_empty_directories(git_path("%s", newrefname))) {
1915 error("Directory not empty: %s", newrefname);
c976d415
LH
1916 goto rollback;
1917 }
1918 } else {
dfefa935 1919 error("unable to delete existing %s", newrefname);
c976d415
LH
1920 goto rollback;
1921 }
1922 }
1923
dfefa935
MH
1924 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1925 error("unable to create directory for %s", newrefname);
c976d415
LH
1926 goto rollback;
1927 }
1928
1929 retry:
dfefa935 1930 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1931 if (errno==EISDIR || errno==ENOTDIR) {
1932 /*
1933 * rename(a, b) when b is an existing
1934 * directory ought to result in ISDIR, but
1935 * Solaris 5.8 gives ENOTDIR. Sheesh.
1936 */
dfefa935
MH
1937 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1938 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1939 goto rollback;
1940 }
1941 goto retry;
1942 } else {
765c2258 1943 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1944 newrefname, strerror(errno));
c976d415
LH
1945 goto rollback;
1946 }
1947 }
1948 logmoved = log;
1949
dfefa935 1950 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1951 if (!lock) {
dfefa935 1952 error("unable to lock %s for update", newrefname);
c976d415
LH
1953 goto rollback;
1954 }
c976d415
LH
1955 lock->force_write = 1;
1956 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1957 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1958 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1959 goto rollback;
1960 }
1961
1962 return 0;
1963
1964 rollback:
dfefa935 1965 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1966 if (!lock) {
dfefa935 1967 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1968 goto rollbacklog;
1969 }
1970
1971 lock->force_write = 1;
1972 flag = log_all_ref_updates;
1973 log_all_ref_updates = 0;
1974 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1975 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1976 log_all_ref_updates = flag;
1977
1978 rollbacklog:
dfefa935 1979 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1980 error("unable to restore logfile %s from %s: %s",
dfefa935 1981 oldrefname, newrefname, strerror(errno));
c976d415 1982 if (!logmoved && log &&
dfefa935 1983 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1984 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1985 oldrefname, strerror(errno));
c976d415
LH
1986
1987 return 1;
1988}
1989
435fc852 1990int close_ref(struct ref_lock *lock)
b531394d
BC
1991{
1992 if (close_lock_file(lock->lk))
1993 return -1;
1994 lock->lock_fd = -1;
1995 return 0;
1996}
1997
435fc852 1998int commit_ref(struct ref_lock *lock)
b531394d
BC
1999{
2000 if (commit_lock_file(lock->lk))
2001 return -1;
2002 lock->lock_fd = -1;
2003 return 0;
2004}
2005
e5f38ec3 2006void unlock_ref(struct ref_lock *lock)
4bd18c43 2007{
4ed7cd3a
BC
2008 /* Do not free lock->lk -- atexit() still looks at them */
2009 if (lock->lk)
2010 rollback_lock_file(lock->lk);
434cd0cd 2011 free(lock->ref_name);
1655707c 2012 free(lock->orig_ref_name);
4bd18c43
SP
2013 free(lock);
2014}
2015
0ec29a47
JH
2016/*
2017 * copy the reflog message msg to buf, which has been allocated sufficiently
2018 * large, while cleaning up the whitespaces. Especially, convert LF to space,
2019 * because reflog file is one line per entry.
2020 */
2021static int copy_msg(char *buf, const char *msg)
2022{
2023 char *cp = buf;
2024 char c;
2025 int wasspace = 1;
2026
2027 *cp++ = '\t';
2028 while ((c = *msg++)) {
2029 if (wasspace && isspace(c))
2030 continue;
2031 wasspace = isspace(c);
2032 if (wasspace)
2033 c = ' ';
2034 *cp++ = c;
2035 }
2036 while (buf < cp && isspace(cp[-1]))
2037 cp--;
2038 *cp++ = '\n';
2039 return cp - buf;
2040}
2041
dfefa935 2042int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 2043{
859c3017 2044 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 2045
dfefa935 2046 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 2047 if (log_all_ref_updates &&
dfefa935
MH
2048 (!prefixcmp(refname, "refs/heads/") ||
2049 !prefixcmp(refname, "refs/remotes/") ||
2050 !prefixcmp(refname, "refs/notes/") ||
2051 !strcmp(refname, "HEAD"))) {
157aaea5 2052 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 2053 return error("unable to create directory for %s",
157aaea5 2054 logfile);
6de08ae6
SP
2055 oflags |= O_CREAT;
2056 }
2057
157aaea5 2058 logfd = open(logfile, oflags, 0666);
6de08ae6 2059 if (logfd < 0) {
1974bf62 2060 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 2061 return 0;
3b463c3f
JH
2062
2063 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 2064 if (remove_empty_directories(logfile)) {
3b463c3f 2065 return error("There are still logs under '%s'",
157aaea5 2066 logfile);
3b463c3f 2067 }
157aaea5 2068 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
2069 }
2070
2071 if (logfd < 0)
2072 return error("Unable to append to %s: %s",
157aaea5 2073 logfile, strerror(errno));
6de08ae6
SP
2074 }
2075
157aaea5 2076 adjust_shared_perm(logfile);
859c3017
EM
2077 close(logfd);
2078 return 0;
2079}
443b92b6 2080
dfefa935 2081static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
2082 const unsigned char *new_sha1, const char *msg)
2083{
2084 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2085 unsigned maxlen, len;
2086 int msglen;
157aaea5 2087 char log_file[PATH_MAX];
859c3017
EM
2088 char *logrec;
2089 const char *committer;
2090
2091 if (log_all_ref_updates < 0)
2092 log_all_ref_updates = !is_bare_repository();
2093
dfefa935 2094 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
2095 if (result)
2096 return result;
2097
2098 logfd = open(log_file, oflags);
2099 if (logfd < 0)
2100 return 0;
0ec29a47 2101 msglen = msg ? strlen(msg) : 0;
774751a8 2102 committer = git_committer_info(0);
8ac65937
JH
2103 maxlen = strlen(committer) + msglen + 100;
2104 logrec = xmalloc(maxlen);
2105 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
2106 sha1_to_hex(old_sha1),
2107 sha1_to_hex(new_sha1),
8ac65937
JH
2108 committer);
2109 if (msglen)
0ec29a47 2110 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 2111 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 2112 free(logrec);
91c8d590 2113 if (close(logfd) != 0 || written != len)
9a13f0b7 2114 return error("Unable to append to %s", log_file);
6de08ae6
SP
2115 return 0;
2116}
2117
c3b0dec5
LT
2118static int is_branch(const char *refname)
2119{
2120 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2121}
2122
4bd18c43
SP
2123int write_ref_sha1(struct ref_lock *lock,
2124 const unsigned char *sha1, const char *logmsg)
2125{
2126 static char term = '\n';
c3b0dec5 2127 struct object *o;
4bd18c43
SP
2128
2129 if (!lock)
95fc7512 2130 return -1;
a89fccd2 2131 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
2132 unlock_ref(lock);
2133 return 0;
95fc7512 2134 }
c3b0dec5
LT
2135 o = parse_object(sha1);
2136 if (!o) {
7be8b3ba 2137 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
2138 lock->ref_name, sha1_to_hex(sha1));
2139 unlock_ref(lock);
2140 return -1;
2141 }
2142 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2143 error("Trying to write non-commit object %s to branch %s",
2144 sha1_to_hex(sha1), lock->ref_name);
2145 unlock_ref(lock);
2146 return -1;
2147 }
93822c22
AW
2148 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2149 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 2150 || close_ref(lock) < 0) {
c33d5174 2151 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
2152 unlock_ref(lock);
2153 return -1;
2154 }
8bf90dc9 2155 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
2156 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2157 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2158 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
2159 unlock_ref(lock);
2160 return -1;
2161 }
605fac8b
NP
2162 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2163 /*
2164 * Special hack: If a branch is updated directly and HEAD
2165 * points to it (may happen on the remote side of a push
2166 * for example) then logically the HEAD reflog should be
2167 * updated too.
2168 * A generic solution implies reverse symref information,
2169 * but finding all symrefs pointing to the given branch
2170 * would be rather costly for this rare event (the direct
2171 * update of a branch) to be worth it. So let's cheat and
2172 * check with HEAD only which should cover 99% of all usage
2173 * scenarios (even 100% of the default ones).
2174 */
2175 unsigned char head_sha1[20];
2176 int head_flag;
2177 const char *head_ref;
8cad4744 2178 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2179 if (head_ref && (head_flag & REF_ISSYMREF) &&
2180 !strcmp(head_ref, lock->ref_name))
2181 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2182 }
b531394d 2183 if (commit_ref(lock)) {
434cd0cd 2184 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2185 unlock_ref(lock);
2186 return -1;
2187 }
4bd18c43
SP
2188 unlock_ref(lock);
2189 return 0;
95fc7512 2190}
d556fae2 2191
8b5157e4
NP
2192int create_symref(const char *ref_target, const char *refs_heads_master,
2193 const char *logmsg)
41b625b0
NP
2194{
2195 const char *lockpath;
2196 char ref[1000];
2197 int fd, len, written;
a4f34cbb 2198 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2199 unsigned char old_sha1[20], new_sha1[20];
2200
2201 if (logmsg && read_ref(ref_target, old_sha1))
2202 hashclr(old_sha1);
41b625b0 2203
d48744d1
JH
2204 if (safe_create_leading_directories(git_HEAD) < 0)
2205 return error("unable to create directory for %s", git_HEAD);
2206
41b625b0
NP
2207#ifndef NO_SYMLINK_HEAD
2208 if (prefer_symlink_refs) {
2209 unlink(git_HEAD);
2210 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2211 goto done;
41b625b0
NP
2212 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2213 }
2214#endif
2215
2216 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2217 if (sizeof(ref) <= len) {
2218 error("refname too long: %s", refs_heads_master);
47fc52e2 2219 goto error_free_return;
41b625b0
NP
2220 }
2221 lockpath = mkpath("%s.lock", git_HEAD);
2222 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2223 if (fd < 0) {
2224 error("Unable to open %s for writing", lockpath);
47fc52e2 2225 goto error_free_return;
41b625b0
NP
2226 }
2227 written = write_in_full(fd, ref, len);
91c8d590 2228 if (close(fd) != 0 || written != len) {
41b625b0 2229 error("Unable to write to %s", lockpath);
47fc52e2 2230 goto error_unlink_return;
41b625b0
NP
2231 }
2232 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2233 error("Unable to create %s", git_HEAD);
47fc52e2 2234 goto error_unlink_return;
41b625b0
NP
2235 }
2236 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2237 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2238 error_unlink_return:
691f1a28 2239 unlink_or_warn(lockpath);
47fc52e2
JH
2240 error_free_return:
2241 free(git_HEAD);
2242 return -1;
41b625b0 2243 }
8b5157e4 2244
ee96d11b 2245#ifndef NO_SYMLINK_HEAD
8b5157e4 2246 done:
ee96d11b 2247#endif
8b5157e4
NP
2248 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2249 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2250
47fc52e2 2251 free(git_HEAD);
41b625b0
NP
2252 return 0;
2253}
2254
16d7cc90
JH
2255static char *ref_msg(const char *line, const char *endp)
2256{
2257 const char *ep;
16d7cc90 2258 line += 82;
182af834
PH
2259 ep = memchr(line, '\n', endp - line);
2260 if (!ep)
2261 ep = endp;
2262 return xmemdupz(line, ep - line);
16d7cc90
JH
2263}
2264
dfefa935
MH
2265int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2266 unsigned char *sha1, char **msg,
2267 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2268{
e5229042 2269 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2270 char *tz_c;
e29cb53a 2271 int logfd, tz, reccnt = 0;
d556fae2
SP
2272 struct stat st;
2273 unsigned long date;
e5229042 2274 unsigned char logged_sha1[20];
cb48cb58 2275 void *log_mapped;
dc49cd76 2276 size_t mapsz;
d556fae2 2277
dfefa935 2278 logfile = git_path("logs/%s", refname);
d556fae2
SP
2279 logfd = open(logfile, O_RDONLY, 0);
2280 if (logfd < 0)
d824cbba 2281 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2282 fstat(logfd, &st);
2283 if (!st.st_size)
2284 die("Log %s is empty.", logfile);
dc49cd76
SP
2285 mapsz = xsize_t(st.st_size);
2286 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2287 logdata = log_mapped;
d556fae2
SP
2288 close(logfd);
2289
e5229042 2290 lastrec = NULL;
d556fae2
SP
2291 rec = logend = logdata + st.st_size;
2292 while (logdata < rec) {
e29cb53a 2293 reccnt++;
d556fae2
SP
2294 if (logdata < rec && *(rec-1) == '\n')
2295 rec--;
e5229042
SP
2296 lastgt = NULL;
2297 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2298 rec--;
e5229042
SP
2299 if (*rec == '>')
2300 lastgt = rec;
2301 }
2302 if (!lastgt)
d556fae2 2303 die("Log %s is corrupt.", logfile);
e5229042 2304 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2305 if (date <= at_time || cnt == 0) {
76a44c5c 2306 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2307 if (msg)
2308 *msg = ref_msg(rec, logend);
2309 if (cutoff_time)
2310 *cutoff_time = date;
2311 if (cutoff_tz)
2312 *cutoff_tz = tz;
2313 if (cutoff_cnt)
76a44c5c 2314 *cutoff_cnt = reccnt - 1;
e5229042
SP
2315 if (lastrec) {
2316 if (get_sha1_hex(lastrec, logged_sha1))
2317 die("Log %s is corrupt.", logfile);
2318 if (get_sha1_hex(rec + 41, sha1))
2319 die("Log %s is corrupt.", logfile);
a89fccd2 2320 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2321 warning("Log %s has gap after %s.",
73013afd 2322 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2323 }
e5f38ec3
JH
2324 }
2325 else if (date == at_time) {
e5229042
SP
2326 if (get_sha1_hex(rec + 41, sha1))
2327 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2328 }
2329 else {
e5229042
SP
2330 if (get_sha1_hex(rec + 41, logged_sha1))
2331 die("Log %s is corrupt.", logfile);
a89fccd2 2332 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2333 warning("Log %s unexpectedly ended on %s.",
73013afd 2334 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2335 }
2336 }
dc49cd76 2337 munmap(log_mapped, mapsz);
d556fae2
SP
2338 return 0;
2339 }
e5229042 2340 lastrec = rec;
ab2a1a32
JH
2341 if (cnt > 0)
2342 cnt--;
d556fae2
SP
2343 }
2344
e5229042
SP
2345 rec = logdata;
2346 while (rec < logend && *rec != '>' && *rec != '\n')
2347 rec++;
2348 if (rec == logend || *rec == '\n')
d556fae2 2349 die("Log %s is corrupt.", logfile);
e5229042 2350 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2351 tz = strtoul(tz_c, NULL, 10);
2352 if (get_sha1_hex(logdata, sha1))
2353 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2354 if (is_null_sha1(sha1)) {
2355 if (get_sha1_hex(logdata + 41, sha1))
2356 die("Log %s is corrupt.", logfile);
2357 }
16d7cc90
JH
2358 if (msg)
2359 *msg = ref_msg(logdata, logend);
dc49cd76 2360 munmap(log_mapped, mapsz);
16d7cc90
JH
2361
2362 if (cutoff_time)
2363 *cutoff_time = date;
2364 if (cutoff_tz)
2365 *cutoff_tz = tz;
2366 if (cutoff_cnt)
2367 *cutoff_cnt = reccnt;
2368 return 1;
d556fae2 2369}
2ff81662 2370
dfefa935 2371int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
2372{
2373 const char *logfile;
2374 FILE *logfp;
8ca78803 2375 struct strbuf sb = STRBUF_INIT;
2266bf27 2376 int ret = 0;
2ff81662 2377
dfefa935 2378 logfile = git_path("logs/%s", refname);
2ff81662
JH
2379 logfp = fopen(logfile, "r");
2380 if (!logfp)
883d60fa 2381 return -1;
101d15e0
JH
2382
2383 if (ofs) {
2384 struct stat statbuf;
2385 if (fstat(fileno(logfp), &statbuf) ||
2386 statbuf.st_size < ofs ||
2387 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 2388 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 2389 fclose(logfp);
8ca78803 2390 strbuf_release(&sb);
101d15e0 2391 return -1;
9d33f7c2 2392 }
101d15e0
JH
2393 }
2394
8ca78803 2395 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 2396 unsigned char osha1[20], nsha1[20];
883d60fa
JS
2397 char *email_end, *message;
2398 unsigned long timestamp;
8ca78803 2399 int tz;
2ff81662
JH
2400
2401 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
2402 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2403 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2404 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2405 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
2406 email_end[1] != ' ' ||
2407 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2408 !message || message[0] != ' ' ||
2409 (message[1] != '+' && message[1] != '-') ||
2410 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2411 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2412 continue; /* corrupt? */
883d60fa
JS
2413 email_end[1] = '\0';
2414 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2415 if (message[6] != '\t')
2416 message += 6;
2417 else
2418 message += 7;
8ca78803
RS
2419 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2420 cb_data);
883d60fa 2421 if (ret)
2266bf27 2422 break;
2ff81662
JH
2423 }
2424 fclose(logfp);
8ca78803 2425 strbuf_release(&sb);
2266bf27 2426 return ret;
2ff81662 2427}
e29cb53a 2428
dfefa935 2429int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2430{
dfefa935 2431 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2432}
2433
989c0e5d
MH
2434/*
2435 * Call fn for each reflog in the namespace indicated by name. name
2436 * must be empty or end with '/'. Name will be used as a scratch
2437 * space, but its contents will be restored before return.
2438 */
2439static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 2440{
989c0e5d 2441 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 2442 int retval = 0;
93c603fc 2443 struct dirent *de;
989c0e5d 2444 int oldlen = name->len;
eb8381c8 2445
93c603fc 2446 if (!d)
989c0e5d 2447 return name->len ? errno : 0;
eb8381c8 2448
93c603fc
MH
2449 while ((de = readdir(d)) != NULL) {
2450 struct stat st;
eb8381c8 2451
93c603fc
MH
2452 if (de->d_name[0] == '.')
2453 continue;
93c603fc
MH
2454 if (has_extension(de->d_name, ".lock"))
2455 continue;
989c0e5d
MH
2456 strbuf_addstr(name, de->d_name);
2457 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2458 ; /* silently ignore */
93c603fc 2459 } else {
eb8381c8 2460 if (S_ISDIR(st.st_mode)) {
989c0e5d
MH
2461 strbuf_addch(name, '/');
2462 retval = do_for_each_reflog(name, fn, cb_data);
eb8381c8
NP
2463 } else {
2464 unsigned char sha1[20];
989c0e5d
MH
2465 if (read_ref_full(name->buf, sha1, 0, NULL))
2466 retval = error("bad ref for %s", name->buf);
eb8381c8 2467 else
989c0e5d 2468 retval = fn(name->buf, sha1, 0, cb_data);
eb8381c8
NP
2469 }
2470 if (retval)
2471 break;
2472 }
989c0e5d 2473 strbuf_setlen(name, oldlen);
eb8381c8 2474 }
93c603fc 2475 closedir(d);
eb8381c8
NP
2476 return retval;
2477}
2478
2479int for_each_reflog(each_ref_fn fn, void *cb_data)
2480{
989c0e5d
MH
2481 int retval;
2482 struct strbuf name;
2483 strbuf_init(&name, PATH_MAX);
2484 retval = do_for_each_reflog(&name, fn, cb_data);
2485 strbuf_release(&name);
2486 return retval;
eb8381c8 2487}
3d9f037c
CR
2488
2489int update_ref(const char *action, const char *refname,
2490 const unsigned char *sha1, const unsigned char *oldval,
2491 int flags, enum action_on_err onerr)
2492{
2493 static struct ref_lock *lock;
2494 lock = lock_any_ref_for_update(refname, oldval, flags);
2495 if (!lock) {
2496 const char *str = "Cannot lock the ref '%s'.";
2497 switch (onerr) {
2498 case MSG_ON_ERR: error(str, refname); break;
2499 case DIE_ON_ERR: die(str, refname); break;
2500 case QUIET_ON_ERR: break;
2501 }
2502 return 1;
2503 }
2504 if (write_ref_sha1(lock, sha1, action) < 0) {
2505 const char *str = "Cannot update the ref '%s'.";
2506 switch (onerr) {
2507 case MSG_ON_ERR: error(str, refname); break;
2508 case DIE_ON_ERR: die(str, refname); break;
2509 case QUIET_ON_ERR: break;
2510 }
2511 return 1;
2512 }
2513 return 0;
2514}
cda69f48 2515
5483f799 2516struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2517{
2518 for ( ; list; list = list->next)
2519 if (!strcmp(list->name, name))
5483f799 2520 return (struct ref *)list;
cda69f48
JK
2521 return NULL;
2522}
7c2b3029
JK
2523
2524/*
2525 * generate a format suitable for scanf from a ref_rev_parse_rules
2526 * rule, that is replace the "%.*s" spec with a "%s" spec
2527 */
2528static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2529{
2530 char *spec;
2531
2532 spec = strstr(rule, "%.*s");
2533 if (!spec || strstr(spec + 4, "%.*s"))
2534 die("invalid rule in ref_rev_parse_rules: %s", rule);
2535
2536 /* copy all until spec */
2537 strncpy(scanf_fmt, rule, spec - rule);
2538 scanf_fmt[spec - rule] = '\0';
2539 /* copy new spec */
2540 strcat(scanf_fmt, "%s");
2541 /* copy remaining rule */
2542 strcat(scanf_fmt, spec + 4);
2543
2544 return;
2545}
2546
dfefa935 2547char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2548{
2549 int i;
2550 static char **scanf_fmts;
2551 static int nr_rules;
2552 char *short_name;
2553
2554 /* pre generate scanf formats from ref_rev_parse_rules[] */
2555 if (!nr_rules) {
2556 size_t total_len = 0;
2557
2558 /* the rule list is NULL terminated, count them first */
2559 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2560 /* no +1 because strlen("%s") < strlen("%.*s") */
2561 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2562
2563 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2564
2565 total_len = 0;
2566 for (i = 0; i < nr_rules; i++) {
2567 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2568 + total_len;
2569 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2570 total_len += strlen(ref_rev_parse_rules[i]);
2571 }
2572 }
2573
2574 /* bail out if there are no rules */
2575 if (!nr_rules)
dfefa935 2576 return xstrdup(refname);
7c2b3029 2577
dfefa935
MH
2578 /* buffer for scanf result, at most refname must fit */
2579 short_name = xstrdup(refname);
7c2b3029
JK
2580
2581 /* skip first rule, it will always match */
2582 for (i = nr_rules - 1; i > 0 ; --i) {
2583 int j;
6e7b3309 2584 int rules_to_fail = i;
7c2b3029
JK
2585 int short_name_len;
2586
dfefa935 2587 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2588 continue;
2589
2590 short_name_len = strlen(short_name);
2591
6e7b3309
BW
2592 /*
2593 * in strict mode, all (except the matched one) rules
2594 * must fail to resolve to a valid non-ambiguous ref
2595 */
2596 if (strict)
2597 rules_to_fail = nr_rules;
2598
7c2b3029
JK
2599 /*
2600 * check if the short name resolves to a valid ref,
2601 * but use only rules prior to the matched one
2602 */
6e7b3309 2603 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2604 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2605 char refname[PATH_MAX];
2606
6e7b3309
BW
2607 /* skip matched rule */
2608 if (i == j)
2609 continue;
2610
7c2b3029
JK
2611 /*
2612 * the short name is ambiguous, if it resolves
2613 * (with this previous rule) to a valid ref
2614 * read_ref() returns 0 on success
2615 */
2616 mksnpath(refname, sizeof(refname),
2617 rule, short_name_len, short_name);
c6893323 2618 if (ref_exists(refname))
7c2b3029
JK
2619 break;
2620 }
2621
2622 /*
2623 * short name is non-ambiguous if all previous rules
2624 * haven't resolved to a valid ref
2625 */
6e7b3309 2626 if (j == rules_to_fail)
7c2b3029
JK
2627 return short_name;
2628 }
2629
2630 free(short_name);
dfefa935 2631 return xstrdup(refname);
7c2b3029 2632}