]> git.ipfire.org Git - thirdparty/git.git/blame - refs.c
refs: document the fields of struct ref_value
[thirdparty/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
bc5fd6d3 529#define DO_FOR_EACH_INCLUDE_BROKEN 01
c774aab9 530
bc5fd6d3 531static struct ref_entry *current_ref;
c774aab9 532
bc5fd6d3
MH
533static int do_one_ref(const char *base, each_ref_fn fn, int trim,
534 int flags, void *cb_data, struct ref_entry *entry)
535{
429213e4 536 int retval;
bc5fd6d3
MH
537 if (prefixcmp(entry->name, base))
538 return 0;
c774aab9 539
bc5fd6d3
MH
540 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
541 if (entry->flag & REF_ISBROKEN)
542 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 543 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
544 error("%s does not point to a valid object!", entry->name);
545 return 0;
546 }
547 }
548 current_ref = entry;
593f1bb8 549 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
550 current_ref = NULL;
551 return retval;
bc5fd6d3 552}
c774aab9 553
c36b5bc2 554/*
d3177275 555 * Call fn for each reference in dir that has index in the range
432ad41e
MH
556 * offset <= index < dir->nr. Recurse into subdirectories that are in
557 * that index range, sorting them before iterating. This function
558 * does not sort dir itself; it should be sorted beforehand.
c36b5bc2 559 */
d3177275
MH
560static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
561 const char *base,
562 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
563{
564 int i;
d3177275
MH
565 assert(dir->sorted == dir->nr);
566 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
567 struct ref_entry *entry = dir->entries[i];
568 int retval;
569 if (entry->flag & REF_DIR) {
d7826d54
MH
570 struct ref_dir *subdir = get_ref_dir(entry);
571 sort_ref_dir(subdir);
572 retval = do_for_each_ref_in_dir(subdir, 0,
432ad41e
MH
573 base, fn, trim, flags, cb_data);
574 } else {
575 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
576 }
c36b5bc2
MH
577 if (retval)
578 return retval;
579 }
580 return 0;
581}
582
b3fd060f 583/*
d3177275 584 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
585 * by refname. Recurse into subdirectories. If a value entry appears
586 * in both dir1 and dir2, then only process the version that is in
587 * dir2. The input dirs must already be sorted, but subdirs will be
588 * sorted as needed.
b3fd060f 589 */
d3177275
MH
590static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
591 struct ref_dir *dir2,
592 const char *base, each_ref_fn fn, int trim,
593 int flags, void *cb_data)
b3fd060f
MH
594{
595 int retval;
596 int i1 = 0, i2 = 0;
597
d3177275
MH
598 assert(dir1->sorted == dir1->nr);
599 assert(dir2->sorted == dir2->nr);
432ad41e
MH
600 while (1) {
601 struct ref_entry *e1, *e2;
602 int cmp;
603 if (i1 == dir1->nr) {
604 return do_for_each_ref_in_dir(dir2, i2,
605 base, fn, trim, flags, cb_data);
606 }
607 if (i2 == dir2->nr) {
608 return do_for_each_ref_in_dir(dir1, i1,
609 base, fn, trim, flags, cb_data);
610 }
611 e1 = dir1->entries[i1];
612 e2 = dir2->entries[i2];
613 cmp = strcmp(e1->name, e2->name);
614 if (cmp == 0) {
615 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
616 /* Both are directories; descend them in parallel. */
d7826d54
MH
617 struct ref_dir *subdir1 = get_ref_dir(e1);
618 struct ref_dir *subdir2 = get_ref_dir(e2);
619 sort_ref_dir(subdir1);
620 sort_ref_dir(subdir2);
432ad41e 621 retval = do_for_each_ref_in_dirs(
d7826d54 622 subdir1, subdir2,
432ad41e
MH
623 base, fn, trim, flags, cb_data);
624 i1++;
625 i2++;
626 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
627 /* Both are references; ignore the one from dir1. */
628 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
629 i1++;
630 i2++;
631 } else {
632 die("conflict between reference and directory: %s",
633 e1->name);
634 }
b3fd060f 635 } else {
432ad41e
MH
636 struct ref_entry *e;
637 if (cmp < 0) {
638 e = e1;
b3fd060f 639 i1++;
432ad41e
MH
640 } else {
641 e = e2;
642 i2++;
643 }
644 if (e->flag & REF_DIR) {
d7826d54
MH
645 struct ref_dir *subdir = get_ref_dir(e);
646 sort_ref_dir(subdir);
432ad41e 647 retval = do_for_each_ref_in_dir(
d7826d54 648 subdir, 0,
432ad41e
MH
649 base, fn, trim, flags, cb_data);
650 } else {
651 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
b3fd060f
MH
652 }
653 }
654 if (retval)
655 return retval;
656 }
d3177275
MH
657 if (i1 < dir1->nr)
658 return do_for_each_ref_in_dir(dir1, i1,
659 base, fn, trim, flags, cb_data);
660 if (i2 < dir2->nr)
661 return do_for_each_ref_in_dir(dir2, i2,
662 base, fn, trim, flags, cb_data);
b3fd060f
MH
663 return 0;
664}
665
d66da478
MH
666/*
667 * Return true iff refname1 and refname2 conflict with each other.
668 * Two reference names conflict if one of them exactly matches the
669 * leading components of the other; e.g., "foo/bar" conflicts with
670 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
671 * "foo/barbados".
672 */
673static int names_conflict(const char *refname1, const char *refname2)
674{
5a4d4947
MH
675 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
676 ;
677 return (*refname1 == '\0' && *refname2 == '/')
678 || (*refname1 == '/' && *refname2 == '\0');
679}
680
681struct name_conflict_cb {
682 const char *refname;
683 const char *oldrefname;
684 const char *conflicting_refname;
685};
686
687static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
688 int flags, void *cb_data)
689{
690 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
691 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
692 return 0;
693 if (names_conflict(data->refname, existingrefname)) {
694 data->conflicting_refname = existingrefname;
695 return 1;
d66da478 696 }
5a4d4947 697 return 0;
d66da478
MH
698}
699
bc5fd6d3
MH
700/*
701 * Return true iff a reference named refname could be created without
5a4d4947
MH
702 * conflicting with the name of an existing reference in array. If
703 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
704 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
705 * operation).
706 */
707static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 708 struct ref_dir *dir)
bc5fd6d3 709{
5a4d4947
MH
710 struct name_conflict_cb data;
711 data.refname = refname;
712 data.oldrefname = oldrefname;
713 data.conflicting_refname = NULL;
714
d3177275
MH
715 sort_ref_dir(dir);
716 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
717 0, DO_FOR_EACH_INCLUDE_BROKEN,
718 &data)) {
5a4d4947
MH
719 error("'%s' exists; cannot create '%s'",
720 data.conflicting_refname, refname);
721 return 0;
bc5fd6d3
MH
722 }
723 return 1;
e1e22e37
LT
724}
725
5e290ff7
JH
726/*
727 * Future: need to be in "struct repository"
728 * when doing a full libification.
729 */
79c7ca54
MH
730static struct ref_cache {
731 struct ref_cache *next;
d12229f5
MH
732 struct ref_entry *loose;
733 struct ref_entry *packed;
ce40979c
MH
734 /* The submodule name, or "" for the main repo. */
735 char name[FLEX_ARRAY];
79c7ca54 736} *ref_cache;
0e88c130 737
760c4512 738static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 739{
d12229f5
MH
740 if (refs->packed) {
741 free_ref_entry(refs->packed);
742 refs->packed = NULL;
743 }
5e290ff7 744}
e1e22e37 745
760c4512
MH
746static void clear_loose_ref_cache(struct ref_cache *refs)
747{
d12229f5
MH
748 if (refs->loose) {
749 free_ref_entry(refs->loose);
750 refs->loose = NULL;
751 }
760c4512
MH
752}
753
79c7ca54 754static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 755{
ce40979c 756 int len;
79c7ca54 757 struct ref_cache *refs;
ce40979c
MH
758 if (!submodule)
759 submodule = "";
760 len = strlen(submodule) + 1;
79c7ca54 761 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 762 memcpy(refs->name, submodule, len);
e5dbf605
MH
763 return refs;
764}
765
4349a668 766/*
79c7ca54 767 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
768 * the main repository, use submodule==NULL. The returned structure
769 * will be allocated and initialized but not necessarily populated; it
770 * should not be freed.
771 */
79c7ca54 772static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 773{
79c7ca54 774 struct ref_cache *refs = ref_cache;
0e88c130
MH
775 if (!submodule)
776 submodule = "";
777 while (refs) {
778 if (!strcmp(submodule, refs->name))
779 return refs;
780 refs = refs->next;
4349a668 781 }
0e88c130 782
79c7ca54
MH
783 refs = create_ref_cache(submodule);
784 refs->next = ref_cache;
785 ref_cache = refs;
0e88c130 786 return refs;
4349a668
MH
787}
788
8be8bde7 789void invalidate_ref_cache(const char *submodule)
f130b116 790{
c5f29abd
MH
791 struct ref_cache *refs = get_ref_cache(submodule);
792 clear_packed_ref_cache(refs);
793 clear_loose_ref_cache(refs);
5e290ff7 794}
e1e22e37 795
bc5fd6d3
MH
796/*
797 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
798 * Return a pointer to the refname within the line (null-terminated),
799 * or NULL if there was a problem.
800 */
801static const char *parse_ref_line(char *line, unsigned char *sha1)
802{
803 /*
804 * 42: the answer to everything.
805 *
806 * In this case, it happens to be the answer to
807 * 40 (length of sha1 hex representation)
808 * +1 (space in between hex and name)
809 * +1 (newline at the end of the line)
810 */
811 int len = strlen(line) - 42;
812
813 if (len <= 0)
814 return NULL;
815 if (get_sha1_hex(line, sha1) < 0)
816 return NULL;
817 if (!isspace(line[40]))
818 return NULL;
819 line += 41;
820 if (isspace(*line))
821 return NULL;
822 if (line[len] != '\n')
823 return NULL;
824 line[len] = 0;
825
826 return line;
827}
828
c29c46fa
MH
829/*
830 * Read f, which is a packed-refs file, into dir.
831 *
832 * A comment line of the form "# pack-refs with: " may contain zero or
833 * more traits. We interpret the traits as follows:
834 *
835 * No traits:
836 *
837 * Probably no references are peeled. But if the file contains a
838 * peeled value for a reference, we will use it.
839 *
840 * peeled:
841 *
842 * References under "refs/tags/", if they *can* be peeled, *are*
843 * peeled in this file. References outside of "refs/tags/" are
844 * probably not peeled even if they could have been, but if we find
845 * a peeled value for such a reference we will use it.
846 *
847 * fully-peeled:
848 *
849 * All references in the file that can be peeled are peeled.
850 * Inversely (and this is more important), any references in the
851 * file for which no peeled value is recorded is not peelable. This
852 * trait should typically be written alongside "peeled" for
853 * compatibility with older clients, but we do not require it
854 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
855 */
d3177275 856static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 857{
e9c4c111 858 struct ref_entry *last = NULL;
f4204ab9 859 char refline[PATH_MAX];
c29c46fa 860 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
f4204ab9
JH
861
862 while (fgets(refline, sizeof(refline), f)) {
863 unsigned char sha1[20];
dfefa935 864 const char *refname;
f4204ab9
JH
865 static const char header[] = "# pack-refs with:";
866
867 if (!strncmp(refline, header, sizeof(header)-1)) {
868 const char *traits = refline + sizeof(header) - 1;
c29c46fa
MH
869 if (strstr(traits, " fully-peeled "))
870 peeled = PEELED_FULLY;
871 else if (strstr(traits, " peeled "))
872 peeled = PEELED_TAGS;
f4204ab9
JH
873 /* perhaps other traits later as well */
874 continue;
875 }
876
dfefa935
MH
877 refname = parse_ref_line(refline, sha1);
878 if (refname) {
c29c46fa
MH
879 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
880 if (peeled == PEELED_FULLY ||
881 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
882 last->flag |= REF_KNOWS_PEELED;
d3177275 883 add_ref(dir, last);
f4204ab9
JH
884 continue;
885 }
886 if (last &&
887 refline[0] == '^' &&
888 strlen(refline) == 42 &&
889 refline[41] == '\n' &&
c29c46fa 890 !get_sha1_hex(refline + 1, sha1)) {
593f1bb8 891 hashcpy(last->u.value.peeled, sha1);
c29c46fa
MH
892 /*
893 * Regardless of what the file header said,
894 * we definitely know the value of *this*
895 * reference:
896 */
897 last->flag |= REF_KNOWS_PEELED;
898 }
f4204ab9 899 }
f4204ab9
JH
900}
901
d3177275 902static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 903{
d12229f5 904 if (!refs->packed) {
4349a668
MH
905 const char *packed_refs_file;
906 FILE *f;
0bad611b 907
b9146f51 908 refs->packed = create_dir_entry(refs, "", 0, 0);
316b097a
MH
909 if (*refs->name)
910 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
911 else
912 packed_refs_file = git_path("packed-refs");
913 f = fopen(packed_refs_file, "r");
e1e22e37 914 if (f) {
d7826d54 915 read_packed_refs(f, get_ref_dir(refs->packed));
e1e22e37 916 fclose(f);
e1e22e37 917 }
e1e22e37 918 }
d7826d54 919 return get_ref_dir(refs->packed);
e1e22e37
LT
920}
921
30249ee6
MH
922void add_packed_ref(const char *refname, const unsigned char *sha1)
923{
924 add_ref(get_packed_refs(get_ref_cache(NULL)),
925 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
926}
927
abc39098 928/*
28e6a34e
MH
929 * Read the loose references from the namespace dirname into dir
930 * (without recursing). dirname must end with '/'. dir must be the
931 * directory entry corresponding to dirname.
abc39098 932 */
423a1afc 933static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 934{
423a1afc 935 struct ref_cache *refs = dir->ref_cache;
d3177275 936 DIR *d;
0bad611b 937 const char *path;
d5fdae67 938 struct dirent *de;
abc39098 939 int dirnamelen = strlen(dirname);
72b64b44 940 struct strbuf refname;
0bad611b 941
3b124823 942 if (*refs->name)
66a3d20b 943 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 944 else
66a3d20b 945 path = git_path("%s", dirname);
0bad611b 946
d3177275 947 d = opendir(path);
d5fdae67
MH
948 if (!d)
949 return;
950
66a3d20b
MH
951 strbuf_init(&refname, dirnamelen + 257);
952 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
953
954 while ((de = readdir(d)) != NULL) {
955 unsigned char sha1[20];
956 struct stat st;
957 int flag;
d5fdae67
MH
958 const char *refdir;
959
960 if (de->d_name[0] == '.')
961 continue;
d5fdae67
MH
962 if (has_extension(de->d_name, ".lock"))
963 continue;
72b64b44 964 strbuf_addstr(&refname, de->d_name);
d5fdae67 965 refdir = *refs->name
72b64b44
MH
966 ? git_path_submodule(refs->name, "%s", refname.buf)
967 : git_path("%s", refname.buf);
968 if (stat(refdir, &st) < 0) {
969 ; /* silently ignore */
970 } else if (S_ISDIR(st.st_mode)) {
abc39098 971 strbuf_addch(&refname, '/');
28e6a34e 972 add_entry_to_dir(dir,
b9146f51
RS
973 create_dir_entry(refs, refname.buf,
974 refname.len, 1));
72b64b44 975 } else {
3b124823 976 if (*refs->name) {
f8948e2f 977 hashclr(sha1);
0bad611b 978 flag = 0;
72b64b44 979 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
0bad611b 980 hashclr(sha1);
98ac34b2 981 flag |= REF_ISBROKEN;
0bad611b 982 }
72b64b44 983 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
984 hashclr(sha1);
985 flag |= REF_ISBROKEN;
986 }
9f2fb4a3
MH
987 add_entry_to_dir(dir,
988 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 989 }
66a3d20b 990 strbuf_setlen(&refname, dirnamelen);
e1e22e37 991 }
72b64b44 992 strbuf_release(&refname);
d5fdae67 993 closedir(d);
e1e22e37
LT
994}
995
d3177275 996static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 997{
d12229f5 998 if (!refs->loose) {
28e6a34e
MH
999 /*
1000 * Mark the top-level directory complete because we
1001 * are about to read the only subdirectory that can
1002 * hold references:
1003 */
b9146f51 1004 refs->loose = create_dir_entry(refs, "", 0, 0);
28e6a34e
MH
1005 /*
1006 * Create an incomplete entry for "refs/":
1007 */
1008 add_entry_to_dir(get_ref_dir(refs->loose),
b9146f51 1009 create_dir_entry(refs, "refs/", 5, 1));
e1e22e37 1010 }
d7826d54 1011 return get_ref_dir(refs->loose);
e1e22e37
LT
1012}
1013
ca8db142
LT
1014/* We allow "recursive" symbolic refs. Only within reason, though */
1015#define MAXDEPTH 5
0ebde32c
LT
1016#define MAXREFLEN (1024)
1017
e5fa45c1
JH
1018/*
1019 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
1020 * from the loose refs in ref_cache refs. Find <refname> in the
1021 * packed-refs file for the submodule.
e5fa45c1 1022 */
b0626608 1023static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 1024 const char *refname, unsigned char *sha1)
0ebde32c 1025{
2c5c66be 1026 struct ref_entry *ref;
d3177275 1027 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 1028
432ad41e 1029 ref = find_ref(dir, refname);
b0626608
MH
1030 if (ref == NULL)
1031 return -1;
1032
593f1bb8 1033 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 1034 return 0;
0ebde32c
LT
1035}
1036
b0626608 1037static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 1038 const char *refname, unsigned char *sha1,
dfefa935 1039 int recursion)
0ebde32c 1040{
064d51dc 1041 int fd, len;
0ebde32c 1042 char buffer[128], *p;
064d51dc 1043 char *path;
0ebde32c 1044
064d51dc 1045 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 1046 return -1;
064d51dc
MH
1047 path = *refs->name
1048 ? git_path_submodule(refs->name, "%s", refname)
1049 : git_path("%s", refname);
1050 fd = open(path, O_RDONLY);
0ebde32c 1051 if (fd < 0)
b0626608 1052 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
1053
1054 len = read(fd, buffer, sizeof(buffer)-1);
1055 close(fd);
1056 if (len < 0)
1057 return -1;
1058 while (len && isspace(buffer[len-1]))
1059 len--;
1060 buffer[len] = 0;
1061
1062 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 1063 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
1064 return 0;
1065
1066 /* Symref? */
1067 if (strncmp(buffer, "ref:", 4))
1068 return -1;
1069 p = buffer + 4;
1070 while (isspace(*p))
1071 p++;
1072
064d51dc 1073 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
1074}
1075
85be1fe3 1076int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
1077{
1078 int len = strlen(path), retval;
064d51dc 1079 char *submodule;
b0626608 1080 struct ref_cache *refs;
0ebde32c
LT
1081
1082 while (len && path[len-1] == '/')
1083 len--;
1084 if (!len)
1085 return -1;
b0626608
MH
1086 submodule = xstrndup(path, len);
1087 refs = get_ref_cache(submodule);
1088 free(submodule);
1089
064d51dc 1090 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
1091 return retval;
1092}
ca8db142 1093
4886b89f 1094/*
c224ca7f
MH
1095 * Try to read ref from the packed references. On success, set sha1
1096 * and return 0; otherwise, return -1.
4886b89f 1097 */
dfefa935 1098static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 1099{
d3177275 1100 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 1101 struct ref_entry *entry = find_ref(packed, refname);
2c5c66be 1102 if (entry) {
593f1bb8 1103 hashcpy(sha1, entry->u.value.sha1);
2c5c66be 1104 return 0;
c224ca7f
MH
1105 }
1106 return -1;
1107}
1108
8d68493f 1109const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 1110{
0104ca09
HO
1111 int depth = MAXDEPTH;
1112 ssize_t len;
a876ed83 1113 char buffer[256];
dfefa935 1114 static char refname_buffer[256];
ca8db142 1115
8da19775
JH
1116 if (flag)
1117 *flag = 0;
1118
dfefa935 1119 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
1120 return NULL;
1121
a876ed83 1122 for (;;) {
55956350 1123 char path[PATH_MAX];
a876ed83
JH
1124 struct stat st;
1125 char *buf;
1126 int fd;
8a65ff76 1127
a876ed83
JH
1128 if (--depth < 0)
1129 return NULL;
ca8db142 1130
dfefa935 1131 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 1132
a876ed83 1133 if (lstat(path, &st) < 0) {
c224ca7f
MH
1134 if (errno != ENOENT)
1135 return NULL;
1136 /*
1137 * The loose reference file does not exist;
1138 * check for a packed reference.
1139 */
dfefa935 1140 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
1141 if (flag)
1142 *flag |= REF_ISPACKED;
dfefa935 1143 return refname;
434cd0cd 1144 }
c224ca7f
MH
1145 /* The reference is not a packed reference, either. */
1146 if (reading) {
a876ed83 1147 return NULL;
c224ca7f
MH
1148 } else {
1149 hashclr(sha1);
dfefa935 1150 return refname;
c224ca7f 1151 }
a876ed83 1152 }
ca8db142 1153
a876ed83
JH
1154 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1155 if (S_ISLNK(st.st_mode)) {
1156 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
1157 if (len < 0)
1158 return NULL;
b54cb795 1159 buffer[len] = 0;
1f58a038
MH
1160 if (!prefixcmp(buffer, "refs/") &&
1161 !check_refname_format(buffer, 0)) {
dfefa935
MH
1162 strcpy(refname_buffer, buffer);
1163 refname = refname_buffer;
8da19775
JH
1164 if (flag)
1165 *flag |= REF_ISSYMREF;
a876ed83
JH
1166 continue;
1167 }
ca8db142 1168 }
a876ed83 1169
7a21632f
DS
1170 /* Is it a directory? */
1171 if (S_ISDIR(st.st_mode)) {
1172 errno = EISDIR;
1173 return NULL;
1174 }
1175
a876ed83
JH
1176 /*
1177 * Anything else, just open it and try to use it as
1178 * a ref
1179 */
1180 fd = open(path, O_RDONLY);
1181 if (fd < 0)
1182 return NULL;
93d26e4c 1183 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1184 close(fd);
28775050
MH
1185 if (len < 0)
1186 return NULL;
1187 while (len && isspace(buffer[len-1]))
1188 len--;
1189 buffer[len] = '\0';
a876ed83
JH
1190
1191 /*
1192 * Is it a symbolic ref?
1193 */
28775050 1194 if (prefixcmp(buffer, "ref:"))
a876ed83 1195 break;
55956350
JH
1196 if (flag)
1197 *flag |= REF_ISSYMREF;
a876ed83 1198 buf = buffer + 4;
28775050
MH
1199 while (isspace(*buf))
1200 buf++;
313fb010 1201 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1202 if (flag)
1203 *flag |= REF_ISBROKEN;
313fb010
MH
1204 return NULL;
1205 }
dfefa935 1206 refname = strcpy(refname_buffer, buf);
8a65ff76 1207 }
f989fea0
MH
1208 /* Please note that FETCH_HEAD has a second line containing other data. */
1209 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1210 if (flag)
1211 *flag |= REF_ISBROKEN;
a876ed83 1212 return NULL;
629cd3ac 1213 }
dfefa935 1214 return refname;
a876ed83
JH
1215}
1216
96ec7b1e
NTND
1217char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1218{
8cad4744 1219 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1220 return ret ? xstrdup(ret) : NULL;
1221}
1222
d08bae7e
IL
1223/* The argument to filter_refs */
1224struct ref_filter {
1225 const char *pattern;
1226 each_ref_fn *fn;
1227 void *cb_data;
1228};
1229
dfefa935 1230int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1231{
8d68493f 1232 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1233 return 0;
1234 return -1;
8a65ff76
LT
1235}
1236
dfefa935 1237int read_ref(const char *refname, unsigned char *sha1)
c6893323 1238{
dfefa935 1239 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1240}
1241
bc5fd6d3 1242int ref_exists(const char *refname)
ef06b918 1243{
bc5fd6d3
MH
1244 unsigned char sha1[20];
1245 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1246}
1247
85be1fe3 1248static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1249 void *data)
d08bae7e
IL
1250{
1251 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1252 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1253 return 0;
85be1fe3 1254 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1255}
1256
dfefa935 1257int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1258{
1259 int flag;
1260 unsigned char base[20];
1261 struct object *o;
1262
dfefa935
MH
1263 if (current_ref && (current_ref->name == refname
1264 || !strcmp(current_ref->name, refname))) {
0ae91be0 1265 if (current_ref->flag & REF_KNOWS_PEELED) {
e6dbffa6
JK
1266 if (is_null_sha1(current_ref->u.value.peeled))
1267 return -1;
593f1bb8 1268 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
1269 return 0;
1270 }
593f1bb8 1271 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
1272 goto fallback;
1273 }
1274
dfefa935 1275 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1276 return -1;
1277
1278 if ((flag & REF_ISPACKED)) {
d3177275 1279 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
432ad41e 1280 struct ref_entry *r = find_ref(dir, refname);
cf0adba7 1281
e9c4c111 1282 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
593f1bb8 1283 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1284 return 0;
cf0adba7 1285 }
cf0adba7
JH
1286 }
1287
0ae91be0 1288fallback:
6c4a060d
JK
1289 o = lookup_unknown_object(base);
1290 if (o->type == OBJ_NONE) {
1291 int type = sha1_object_info(base, NULL);
1292 if (type < 0)
1293 return -1;
1294 o->type = type;
1295 }
1296
1297 if (o->type == OBJ_TAG) {
44da6f69 1298 o = deref_tag_noverify(o);
cf0adba7
JH
1299 if (o) {
1300 hashcpy(sha1, o->sha1);
1301 return 0;
1302 }
1303 }
1304 return -1;
1305}
1306
bc5fd6d3
MH
1307struct warn_if_dangling_data {
1308 FILE *fp;
1309 const char *refname;
1310 const char *msg_fmt;
1311};
1312
1313static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1314 int flags, void *cb_data)
1315{
1316 struct warn_if_dangling_data *d = cb_data;
1317 const char *resolves_to;
1318 unsigned char junk[20];
1319
1320 if (!(flags & REF_ISSYMREF))
1321 return 0;
1322
1323 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1324 if (!resolves_to || strcmp(resolves_to, d->refname))
1325 return 0;
1326
1327 fprintf(d->fp, d->msg_fmt, refname);
1be65eda 1328 fputc('\n', d->fp);
bc5fd6d3
MH
1329 return 0;
1330}
1331
1332void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1333{
1334 struct warn_if_dangling_data data;
1335
1336 data.fp = fp;
1337 data.refname = refname;
1338 data.msg_fmt = msg_fmt;
1339 for_each_rawref(warn_if_dangling_symref, &data);
1340}
1341
0bad611b
HV
1342static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1343 int trim, int flags, void *cb_data)
8a65ff76 1344{
316b097a 1345 struct ref_cache *refs = get_ref_cache(submodule);
933ac036
MH
1346 struct ref_dir *packed_dir = get_packed_refs(refs);
1347 struct ref_dir *loose_dir = get_loose_refs(refs);
1348 int retval = 0;
1349
1350 if (base && *base) {
1351 packed_dir = find_containing_dir(packed_dir, base, 0);
1352 loose_dir = find_containing_dir(loose_dir, base, 0);
1353 }
1354
1355 if (packed_dir && loose_dir) {
1356 sort_ref_dir(packed_dir);
1357 sort_ref_dir(loose_dir);
1358 retval = do_for_each_ref_in_dirs(
1359 packed_dir, loose_dir,
1360 base, fn, trim, flags, cb_data);
1361 } else if (packed_dir) {
1362 sort_ref_dir(packed_dir);
1363 retval = do_for_each_ref_in_dir(
1364 packed_dir, 0,
1365 base, fn, trim, flags, cb_data);
1366 } else if (loose_dir) {
1367 sort_ref_dir(loose_dir);
1368 retval = do_for_each_ref_in_dir(
1369 loose_dir, 0,
1370 base, fn, trim, flags, cb_data);
1371 }
1372
1373 return retval;
8a65ff76
LT
1374}
1375
0bad611b 1376static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1377{
1378 unsigned char sha1[20];
8da19775
JH
1379 int flag;
1380
0bad611b
HV
1381 if (submodule) {
1382 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1383 return fn("HEAD", sha1, 0, cb_data);
1384
1385 return 0;
1386 }
1387
c6893323 1388 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1389 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1390
2f34ba32 1391 return 0;
723c31fe
LT
1392}
1393
0bad611b
HV
1394int head_ref(each_ref_fn fn, void *cb_data)
1395{
1396 return do_head_ref(NULL, fn, cb_data);
1397}
1398
9ef6aeb0
HV
1399int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1400{
1401 return do_head_ref(submodule, fn, cb_data);
1402}
1403
cb5d709f 1404int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1405{
b3cfc406 1406 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1407}
1408
9ef6aeb0
HV
1409int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1410{
b3cfc406 1411 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1412}
1413
2a8177b6
CC
1414int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1415{
0bad611b 1416 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1417}
1418
9ef6aeb0
HV
1419int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1420 each_ref_fn fn, void *cb_data)
1421{
1422 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1423}
1424
cb5d709f 1425int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1426{
2a8177b6 1427 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1428}
1429
9ef6aeb0
HV
1430int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1431{
1432 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1433}
1434
cb5d709f 1435int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1436{
2a8177b6 1437 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1438}
1439
9ef6aeb0
HV
1440int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1441{
1442 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1443}
1444
cb5d709f 1445int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1446{
2a8177b6 1447 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1448}
1449
9ef6aeb0
HV
1450int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1451{
1452 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1453}
1454
29268700
CC
1455int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1456{
0bad611b 1457 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1458}
1459
a1bea2c1
JT
1460int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1461{
1462 struct strbuf buf = STRBUF_INIT;
1463 int ret = 0;
1464 unsigned char sha1[20];
1465 int flag;
1466
1467 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1468 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1469 ret = fn(buf.buf, sha1, flag, cb_data);
1470 strbuf_release(&buf);
1471
1472 return ret;
1473}
1474
1475int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1476{
1477 struct strbuf buf = STRBUF_INIT;
1478 int ret;
1479 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1480 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1481 strbuf_release(&buf);
1482 return ret;
1483}
1484
b09fe971
IL
1485int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1486 const char *prefix, void *cb_data)
d08bae7e
IL
1487{
1488 struct strbuf real_pattern = STRBUF_INIT;
1489 struct ref_filter filter;
d08bae7e
IL
1490 int ret;
1491
b09fe971 1492 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1493 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1494 else if (prefix)
1495 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1496 strbuf_addstr(&real_pattern, pattern);
1497
894a9d33 1498 if (!has_glob_specials(pattern)) {
9517e6b8 1499 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1500 if (real_pattern.buf[real_pattern.len - 1] != '/')
1501 strbuf_addch(&real_pattern, '/');
1502 /* No need to check for '*', there is none. */
1503 strbuf_addch(&real_pattern, '*');
1504 }
1505
1506 filter.pattern = real_pattern.buf;
1507 filter.fn = fn;
1508 filter.cb_data = cb_data;
1509 ret = for_each_ref(filter_refs, &filter);
1510
1511 strbuf_release(&real_pattern);
1512 return ret;
1513}
1514
b09fe971
IL
1515int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1516{
1517 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1518}
1519
f8948e2f
JH
1520int for_each_rawref(each_ref_fn fn, void *cb_data)
1521{
b3cfc406 1522 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1523 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1524}
1525
4577e483 1526const char *prettify_refname(const char *name)
a9c37a72 1527{
a9c37a72
DB
1528 return name + (
1529 !prefixcmp(name, "refs/heads/") ? 11 :
1530 !prefixcmp(name, "refs/tags/") ? 10 :
1531 !prefixcmp(name, "refs/remotes/") ? 13 :
1532 0);
1533}
1534
79803322
SP
1535const char *ref_rev_parse_rules[] = {
1536 "%.*s",
1537 "refs/%.*s",
1538 "refs/tags/%.*s",
1539 "refs/heads/%.*s",
1540 "refs/remotes/%.*s",
1541 "refs/remotes/%.*s/HEAD",
1542 NULL
1543};
1544
1545int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1546{
1547 const char **p;
1548 const int abbrev_name_len = strlen(abbrev_name);
1549
1550 for (p = rules; *p; p++) {
1551 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1552 return 1;
1553 }
1554 }
1555
1556 return 0;
1557}
1558
e5f38ec3 1559static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1560 const unsigned char *old_sha1, int mustexist)
1561{
c6893323 1562 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1563 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1564 unlock_ref(lock);
1565 return NULL;
1566 }
a89fccd2 1567 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1568 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1569 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1570 unlock_ref(lock);
1571 return NULL;
1572 }
1573 return lock;
1574}
1575
7155b727 1576static int remove_empty_directories(const char *file)
bc7127ef
JH
1577{
1578 /* we want to create a file but there is a directory there;
1579 * if that is an empty directory (or a directory that contains
1580 * only empty directories), remove them.
1581 */
7155b727
JS
1582 struct strbuf path;
1583 int result;
bc7127ef 1584
7155b727
JS
1585 strbuf_init(&path, 20);
1586 strbuf_addstr(&path, file);
1587
a0f4afbe 1588 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1589
1590 strbuf_release(&path);
1591
1592 return result;
bc7127ef
JH
1593}
1594
ff74f7f1
JH
1595/*
1596 * *string and *len will only be substituted, and *string returned (for
1597 * later free()ing) if the string passed in is a magic short-hand form
1598 * to name a branch.
1599 */
1600static char *substitute_branch_name(const char **string, int *len)
1601{
1602 struct strbuf buf = STRBUF_INIT;
1603 int ret = interpret_branch_name(*string, &buf);
1604
1605 if (ret == *len) {
1606 size_t size;
1607 *string = strbuf_detach(&buf, &size);
1608 *len = size;
1609 return (char *)*string;
1610 }
1611
1612 return NULL;
1613}
1614
1615int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1616{
1617 char *last_branch = substitute_branch_name(&str, &len);
1618 const char **p, *r;
1619 int refs_found = 0;
1620
1621 *ref = NULL;
1622 for (p = ref_rev_parse_rules; *p; p++) {
1623 char fullref[PATH_MAX];
1624 unsigned char sha1_from_ref[20];
1625 unsigned char *this_result;
1626 int flag;
1627
1628 this_result = refs_found ? sha1_from_ref : sha1;
1629 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1630 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1631 if (r) {
1632 if (!refs_found++)
1633 *ref = xstrdup(r);
1634 if (!warn_ambiguous_refs)
1635 break;
55956350 1636 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1637 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1638 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1639 warning("ignoring broken ref %s.", fullref);
1640 }
ff74f7f1
JH
1641 }
1642 free(last_branch);
1643 return refs_found;
1644}
1645
1646int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1647{
1648 char *last_branch = substitute_branch_name(&str, &len);
1649 const char **p;
1650 int logs_found = 0;
1651
1652 *log = NULL;
1653 for (p = ref_rev_parse_rules; *p; p++) {
1654 struct stat st;
1655 unsigned char hash[20];
1656 char path[PATH_MAX];
1657 const char *ref, *it;
1658
1659 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1660 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1661 if (!ref)
1662 continue;
1663 if (!stat(git_path("logs/%s", path), &st) &&
1664 S_ISREG(st.st_mode))
1665 it = path;
1666 else if (strcmp(ref, path) &&
1667 !stat(git_path("logs/%s", ref), &st) &&
1668 S_ISREG(st.st_mode))
1669 it = ref;
1670 else
1671 continue;
1672 if (!logs_found++) {
1673 *log = xstrdup(it);
1674 hashcpy(sha1, hash);
1675 }
1676 if (!warn_ambiguous_refs)
1677 break;
1678 }
1679 free(last_branch);
1680 return logs_found;
1681}
1682
dfefa935
MH
1683static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1684 const unsigned char *old_sha1,
1685 int flags, int *type_p)
4bd18c43 1686{
434cd0cd 1687 char *ref_file;
dfefa935 1688 const char *orig_refname = refname;
4bd18c43 1689 struct ref_lock *lock;
5cc3cef9 1690 int last_errno = 0;
acd3b9ec 1691 int type, lflags;
4431fcc4 1692 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1693 int missing = 0;
4bd18c43
SP
1694
1695 lock = xcalloc(1, sizeof(struct ref_lock));
1696 lock->lock_fd = -1;
1697
8d68493f 1698 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1699 if (!refname && errno == EISDIR) {
bc7127ef
JH
1700 /* we are trying to lock foo but we used to
1701 * have foo/bar which now does not exist;
1702 * it is normal for the empty directory 'foo'
1703 * to remain.
1704 */
dfefa935 1705 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1706 if (remove_empty_directories(ref_file)) {
1707 last_errno = errno;
dfefa935 1708 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1709 goto error_return;
1710 }
8d68493f 1711 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1712 }
68db31cc
SV
1713 if (type_p)
1714 *type_p = type;
dfefa935 1715 if (!refname) {
5cc3cef9 1716 last_errno = errno;
818f477c 1717 error("unable to resolve reference %s: %s",
dfefa935 1718 orig_refname, strerror(errno));
5cc3cef9 1719 goto error_return;
4bd18c43 1720 }
5bdd8d4a 1721 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1722 /* When the ref did not exist and we are creating it,
1723 * make sure there is no existing ref that is packed
1724 * whose name begins with our refname, nor a ref whose
1725 * name is a proper prefix of our refname.
1726 */
5bdd8d4a 1727 if (missing &&
316b097a 1728 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1729 last_errno = ENOTDIR;
c976d415 1730 goto error_return;
f475e08e 1731 }
22a3844e 1732
c33d5174 1733 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1734
acd3b9ec
JH
1735 lflags = LOCK_DIE_ON_ERROR;
1736 if (flags & REF_NODEREF) {
dfefa935 1737 refname = orig_refname;
acd3b9ec
JH
1738 lflags |= LOCK_NODEREF;
1739 }
dfefa935
MH
1740 lock->ref_name = xstrdup(refname);
1741 lock->orig_ref_name = xstrdup(orig_refname);
1742 ref_file = git_path("%s", refname);
5bdd8d4a 1743 if (missing)
68db31cc
SV
1744 lock->force_write = 1;
1745 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1746 lock->force_write = 1;
4bd18c43 1747
5cc3cef9
JH
1748 if (safe_create_leading_directories(ref_file)) {
1749 last_errno = errno;
1750 error("unable to create directory for %s", ref_file);
1751 goto error_return;
1752 }
4bd18c43 1753
acd3b9ec 1754 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1755 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1756
1757 error_return:
1758 unlock_ref(lock);
1759 errno = last_errno;
1760 return NULL;
4bd18c43
SP
1761}
1762
dfefa935 1763struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1764{
53cce84c 1765 char refpath[PATH_MAX];
dfefa935 1766 if (check_refname_format(refname, 0))
4bd18c43 1767 return NULL;
dfefa935 1768 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1769 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1770}
1771
dfefa935
MH
1772struct ref_lock *lock_any_ref_for_update(const char *refname,
1773 const unsigned char *old_sha1, int flags)
4bd18c43 1774{
dfefa935 1775 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1776 return NULL;
dfefa935 1777 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1778}
1779
d66da478
MH
1780struct repack_without_ref_sb {
1781 const char *refname;
1782 int fd;
1783};
1784
1785static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1786 int flags, void *cb_data)
1787{
1788 struct repack_without_ref_sb *data = cb_data;
1789 char line[PATH_MAX + 100];
1790 int len;
1791
1792 if (!strcmp(data->refname, refname))
1793 return 0;
1794 len = snprintf(line, sizeof(line), "%s %s\n",
1795 sha1_to_hex(sha1), refname);
1796 /* this should not happen but just being defensive */
1797 if (len > sizeof(line))
1798 die("too long a refname '%s'", refname);
1799 write_or_die(data->fd, line, len);
1800 return 0;
1801}
1802
26a063a1
JH
1803static struct lock_file packlock;
1804
c0277d15
JH
1805static int repack_without_ref(const char *refname)
1806{
d66da478 1807 struct repack_without_ref_sb data;
b3f1280e
JK
1808 struct ref_cache *refs = get_ref_cache(NULL);
1809 struct ref_dir *packed = get_packed_refs(refs);
432ad41e 1810 if (find_ref(packed, refname) == NULL)
c0277d15 1811 return 0;
d66da478
MH
1812 data.refname = refname;
1813 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1814 if (data.fd < 0) {
1b018fd9 1815 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1816 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1817 }
b3f1280e
JK
1818 clear_packed_ref_cache(refs);
1819 packed = get_packed_refs(refs);
d3177275 1820 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1821 return commit_lock_file(&packlock);
1822}
1823
eca35a25 1824int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1825{
1826 struct ref_lock *lock;
eca35a25 1827 int err, i = 0, ret = 0, flag = 0;
c0277d15 1828
547d058f 1829 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
c0277d15
JH
1830 if (!lock)
1831 return 1;
045a476f 1832 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1833 /* loose */
547d058f
RS
1834 i = strlen(lock->lk->filename) - 5; /* .lock */
1835 lock->lk->filename[i] = 0;
1836 err = unlink_or_warn(lock->lk->filename);
691f1a28 1837 if (err && errno != ENOENT)
c0277d15 1838 ret = 1;
691f1a28 1839
547d058f 1840 lock->lk->filename[i] = '.';
c0277d15
JH
1841 }
1842 /* removing the loose one could have resurrected an earlier
1843 * packed one. Also, if it was not loose we need to repack
1844 * without it.
1845 */
b274a714 1846 ret |= repack_without_ref(lock->ref_name);
c0277d15 1847
691f1a28 1848 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1849 invalidate_ref_cache(NULL);
c0277d15
JH
1850 unlock_ref(lock);
1851 return ret;
4bd18c43
SP
1852}
1853
765c2258
PH
1854/*
1855 * People using contrib's git-new-workdir have .git/logs/refs ->
1856 * /some/other/path/.git/logs/refs, and that may live on another device.
1857 *
1858 * IOW, to avoid cross device rename errors, the temporary renamed log must
1859 * live into logs/refs.
1860 */
1861#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1862
dfefa935 1863int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1864{
c976d415
LH
1865 unsigned char sha1[20], orig_sha1[20];
1866 int flag = 0, logmoved = 0;
1867 struct ref_lock *lock;
c976d415 1868 struct stat loginfo;
dfefa935 1869 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1870 const char *symref = NULL;
316b097a 1871 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1872
450d4c0f 1873 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1874 return error("reflog for %s is a symlink", oldrefname);
c976d415 1875
8d68493f 1876 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1877 if (flag & REF_ISSYMREF)
fa58186c 1878 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1879 oldrefname);
eca35a25 1880 if (!symref)
dfefa935 1881 return error("refname %s not found", oldrefname);
c976d415 1882
316b097a 1883 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1884 return 1;
1885
316b097a 1886 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1887 return 1;
1888
dfefa935 1889 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1890 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1891 oldrefname, strerror(errno));
c976d415 1892
dfefa935
MH
1893 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1894 error("unable to delete old %s", oldrefname);
c976d415
LH
1895 goto rollback;
1896 }
1897
dfefa935
MH
1898 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1899 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1900 if (errno==EISDIR) {
dfefa935
MH
1901 if (remove_empty_directories(git_path("%s", newrefname))) {
1902 error("Directory not empty: %s", newrefname);
c976d415
LH
1903 goto rollback;
1904 }
1905 } else {
dfefa935 1906 error("unable to delete existing %s", newrefname);
c976d415
LH
1907 goto rollback;
1908 }
1909 }
1910
dfefa935
MH
1911 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1912 error("unable to create directory for %s", newrefname);
c976d415
LH
1913 goto rollback;
1914 }
1915
1916 retry:
dfefa935 1917 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1918 if (errno==EISDIR || errno==ENOTDIR) {
1919 /*
1920 * rename(a, b) when b is an existing
1921 * directory ought to result in ISDIR, but
1922 * Solaris 5.8 gives ENOTDIR. Sheesh.
1923 */
dfefa935
MH
1924 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1925 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1926 goto rollback;
1927 }
1928 goto retry;
1929 } else {
765c2258 1930 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1931 newrefname, strerror(errno));
c976d415
LH
1932 goto rollback;
1933 }
1934 }
1935 logmoved = log;
1936
dfefa935 1937 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1938 if (!lock) {
dfefa935 1939 error("unable to lock %s for update", newrefname);
c976d415
LH
1940 goto rollback;
1941 }
c976d415
LH
1942 lock->force_write = 1;
1943 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1944 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1945 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1946 goto rollback;
1947 }
1948
1949 return 0;
1950
1951 rollback:
dfefa935 1952 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1953 if (!lock) {
dfefa935 1954 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1955 goto rollbacklog;
1956 }
1957
1958 lock->force_write = 1;
1959 flag = log_all_ref_updates;
1960 log_all_ref_updates = 0;
1961 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1962 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1963 log_all_ref_updates = flag;
1964
1965 rollbacklog:
dfefa935 1966 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1967 error("unable to restore logfile %s from %s: %s",
dfefa935 1968 oldrefname, newrefname, strerror(errno));
c976d415 1969 if (!logmoved && log &&
dfefa935 1970 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1971 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1972 oldrefname, strerror(errno));
c976d415
LH
1973
1974 return 1;
1975}
1976
435fc852 1977int close_ref(struct ref_lock *lock)
b531394d
BC
1978{
1979 if (close_lock_file(lock->lk))
1980 return -1;
1981 lock->lock_fd = -1;
1982 return 0;
1983}
1984
435fc852 1985int commit_ref(struct ref_lock *lock)
b531394d
BC
1986{
1987 if (commit_lock_file(lock->lk))
1988 return -1;
1989 lock->lock_fd = -1;
1990 return 0;
1991}
1992
e5f38ec3 1993void unlock_ref(struct ref_lock *lock)
4bd18c43 1994{
4ed7cd3a
BC
1995 /* Do not free lock->lk -- atexit() still looks at them */
1996 if (lock->lk)
1997 rollback_lock_file(lock->lk);
434cd0cd 1998 free(lock->ref_name);
1655707c 1999 free(lock->orig_ref_name);
4bd18c43
SP
2000 free(lock);
2001}
2002
0ec29a47
JH
2003/*
2004 * copy the reflog message msg to buf, which has been allocated sufficiently
2005 * large, while cleaning up the whitespaces. Especially, convert LF to space,
2006 * because reflog file is one line per entry.
2007 */
2008static int copy_msg(char *buf, const char *msg)
2009{
2010 char *cp = buf;
2011 char c;
2012 int wasspace = 1;
2013
2014 *cp++ = '\t';
2015 while ((c = *msg++)) {
2016 if (wasspace && isspace(c))
2017 continue;
2018 wasspace = isspace(c);
2019 if (wasspace)
2020 c = ' ';
2021 *cp++ = c;
2022 }
2023 while (buf < cp && isspace(cp[-1]))
2024 cp--;
2025 *cp++ = '\n';
2026 return cp - buf;
2027}
2028
dfefa935 2029int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 2030{
859c3017 2031 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 2032
dfefa935 2033 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 2034 if (log_all_ref_updates &&
dfefa935
MH
2035 (!prefixcmp(refname, "refs/heads/") ||
2036 !prefixcmp(refname, "refs/remotes/") ||
2037 !prefixcmp(refname, "refs/notes/") ||
2038 !strcmp(refname, "HEAD"))) {
157aaea5 2039 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 2040 return error("unable to create directory for %s",
157aaea5 2041 logfile);
6de08ae6
SP
2042 oflags |= O_CREAT;
2043 }
2044
157aaea5 2045 logfd = open(logfile, oflags, 0666);
6de08ae6 2046 if (logfd < 0) {
1974bf62 2047 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 2048 return 0;
3b463c3f
JH
2049
2050 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 2051 if (remove_empty_directories(logfile)) {
3b463c3f 2052 return error("There are still logs under '%s'",
157aaea5 2053 logfile);
3b463c3f 2054 }
157aaea5 2055 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
2056 }
2057
2058 if (logfd < 0)
2059 return error("Unable to append to %s: %s",
157aaea5 2060 logfile, strerror(errno));
6de08ae6
SP
2061 }
2062
157aaea5 2063 adjust_shared_perm(logfile);
859c3017
EM
2064 close(logfd);
2065 return 0;
2066}
443b92b6 2067
dfefa935 2068static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
2069 const unsigned char *new_sha1, const char *msg)
2070{
2071 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2072 unsigned maxlen, len;
2073 int msglen;
157aaea5 2074 char log_file[PATH_MAX];
859c3017
EM
2075 char *logrec;
2076 const char *committer;
2077
2078 if (log_all_ref_updates < 0)
2079 log_all_ref_updates = !is_bare_repository();
2080
dfefa935 2081 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
2082 if (result)
2083 return result;
2084
2085 logfd = open(log_file, oflags);
2086 if (logfd < 0)
2087 return 0;
0ec29a47 2088 msglen = msg ? strlen(msg) : 0;
774751a8 2089 committer = git_committer_info(0);
8ac65937
JH
2090 maxlen = strlen(committer) + msglen + 100;
2091 logrec = xmalloc(maxlen);
2092 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
2093 sha1_to_hex(old_sha1),
2094 sha1_to_hex(new_sha1),
8ac65937
JH
2095 committer);
2096 if (msglen)
0ec29a47 2097 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 2098 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 2099 free(logrec);
91c8d590 2100 if (close(logfd) != 0 || written != len)
9a13f0b7 2101 return error("Unable to append to %s", log_file);
6de08ae6
SP
2102 return 0;
2103}
2104
c3b0dec5
LT
2105static int is_branch(const char *refname)
2106{
2107 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2108}
2109
4bd18c43
SP
2110int write_ref_sha1(struct ref_lock *lock,
2111 const unsigned char *sha1, const char *logmsg)
2112{
2113 static char term = '\n';
c3b0dec5 2114 struct object *o;
4bd18c43
SP
2115
2116 if (!lock)
95fc7512 2117 return -1;
a89fccd2 2118 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
2119 unlock_ref(lock);
2120 return 0;
95fc7512 2121 }
c3b0dec5
LT
2122 o = parse_object(sha1);
2123 if (!o) {
7be8b3ba 2124 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
2125 lock->ref_name, sha1_to_hex(sha1));
2126 unlock_ref(lock);
2127 return -1;
2128 }
2129 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2130 error("Trying to write non-commit object %s to branch %s",
2131 sha1_to_hex(sha1), lock->ref_name);
2132 unlock_ref(lock);
2133 return -1;
2134 }
93822c22
AW
2135 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2136 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 2137 || close_ref(lock) < 0) {
c33d5174 2138 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
2139 unlock_ref(lock);
2140 return -1;
2141 }
8bf90dc9 2142 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
2143 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2144 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2145 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
2146 unlock_ref(lock);
2147 return -1;
2148 }
605fac8b
NP
2149 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2150 /*
2151 * Special hack: If a branch is updated directly and HEAD
2152 * points to it (may happen on the remote side of a push
2153 * for example) then logically the HEAD reflog should be
2154 * updated too.
2155 * A generic solution implies reverse symref information,
2156 * but finding all symrefs pointing to the given branch
2157 * would be rather costly for this rare event (the direct
2158 * update of a branch) to be worth it. So let's cheat and
2159 * check with HEAD only which should cover 99% of all usage
2160 * scenarios (even 100% of the default ones).
2161 */
2162 unsigned char head_sha1[20];
2163 int head_flag;
2164 const char *head_ref;
8cad4744 2165 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2166 if (head_ref && (head_flag & REF_ISSYMREF) &&
2167 !strcmp(head_ref, lock->ref_name))
2168 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2169 }
b531394d 2170 if (commit_ref(lock)) {
434cd0cd 2171 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2172 unlock_ref(lock);
2173 return -1;
2174 }
4bd18c43
SP
2175 unlock_ref(lock);
2176 return 0;
95fc7512 2177}
d556fae2 2178
8b5157e4
NP
2179int create_symref(const char *ref_target, const char *refs_heads_master,
2180 const char *logmsg)
41b625b0
NP
2181{
2182 const char *lockpath;
2183 char ref[1000];
2184 int fd, len, written;
a4f34cbb 2185 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2186 unsigned char old_sha1[20], new_sha1[20];
2187
2188 if (logmsg && read_ref(ref_target, old_sha1))
2189 hashclr(old_sha1);
41b625b0 2190
d48744d1
JH
2191 if (safe_create_leading_directories(git_HEAD) < 0)
2192 return error("unable to create directory for %s", git_HEAD);
2193
41b625b0
NP
2194#ifndef NO_SYMLINK_HEAD
2195 if (prefer_symlink_refs) {
2196 unlink(git_HEAD);
2197 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2198 goto done;
41b625b0
NP
2199 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2200 }
2201#endif
2202
2203 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2204 if (sizeof(ref) <= len) {
2205 error("refname too long: %s", refs_heads_master);
47fc52e2 2206 goto error_free_return;
41b625b0
NP
2207 }
2208 lockpath = mkpath("%s.lock", git_HEAD);
2209 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2210 if (fd < 0) {
2211 error("Unable to open %s for writing", lockpath);
47fc52e2 2212 goto error_free_return;
41b625b0
NP
2213 }
2214 written = write_in_full(fd, ref, len);
91c8d590 2215 if (close(fd) != 0 || written != len) {
41b625b0 2216 error("Unable to write to %s", lockpath);
47fc52e2 2217 goto error_unlink_return;
41b625b0
NP
2218 }
2219 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2220 error("Unable to create %s", git_HEAD);
47fc52e2 2221 goto error_unlink_return;
41b625b0
NP
2222 }
2223 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2224 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2225 error_unlink_return:
691f1a28 2226 unlink_or_warn(lockpath);
47fc52e2
JH
2227 error_free_return:
2228 free(git_HEAD);
2229 return -1;
41b625b0 2230 }
8b5157e4 2231
ee96d11b 2232#ifndef NO_SYMLINK_HEAD
8b5157e4 2233 done:
ee96d11b 2234#endif
8b5157e4
NP
2235 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2236 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2237
47fc52e2 2238 free(git_HEAD);
41b625b0
NP
2239 return 0;
2240}
2241
16d7cc90
JH
2242static char *ref_msg(const char *line, const char *endp)
2243{
2244 const char *ep;
16d7cc90 2245 line += 82;
182af834
PH
2246 ep = memchr(line, '\n', endp - line);
2247 if (!ep)
2248 ep = endp;
2249 return xmemdupz(line, ep - line);
16d7cc90
JH
2250}
2251
dfefa935
MH
2252int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2253 unsigned char *sha1, char **msg,
2254 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2255{
e5229042 2256 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2257 char *tz_c;
e29cb53a 2258 int logfd, tz, reccnt = 0;
d556fae2
SP
2259 struct stat st;
2260 unsigned long date;
e5229042 2261 unsigned char logged_sha1[20];
cb48cb58 2262 void *log_mapped;
dc49cd76 2263 size_t mapsz;
d556fae2 2264
dfefa935 2265 logfile = git_path("logs/%s", refname);
d556fae2
SP
2266 logfd = open(logfile, O_RDONLY, 0);
2267 if (logfd < 0)
d824cbba 2268 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2269 fstat(logfd, &st);
2270 if (!st.st_size)
2271 die("Log %s is empty.", logfile);
dc49cd76
SP
2272 mapsz = xsize_t(st.st_size);
2273 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2274 logdata = log_mapped;
d556fae2
SP
2275 close(logfd);
2276
e5229042 2277 lastrec = NULL;
d556fae2
SP
2278 rec = logend = logdata + st.st_size;
2279 while (logdata < rec) {
e29cb53a 2280 reccnt++;
d556fae2
SP
2281 if (logdata < rec && *(rec-1) == '\n')
2282 rec--;
e5229042
SP
2283 lastgt = NULL;
2284 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2285 rec--;
e5229042
SP
2286 if (*rec == '>')
2287 lastgt = rec;
2288 }
2289 if (!lastgt)
d556fae2 2290 die("Log %s is corrupt.", logfile);
e5229042 2291 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2292 if (date <= at_time || cnt == 0) {
76a44c5c 2293 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2294 if (msg)
2295 *msg = ref_msg(rec, logend);
2296 if (cutoff_time)
2297 *cutoff_time = date;
2298 if (cutoff_tz)
2299 *cutoff_tz = tz;
2300 if (cutoff_cnt)
76a44c5c 2301 *cutoff_cnt = reccnt - 1;
e5229042
SP
2302 if (lastrec) {
2303 if (get_sha1_hex(lastrec, logged_sha1))
2304 die("Log %s is corrupt.", logfile);
2305 if (get_sha1_hex(rec + 41, sha1))
2306 die("Log %s is corrupt.", logfile);
a89fccd2 2307 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2308 warning("Log %s has gap after %s.",
73013afd 2309 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2310 }
e5f38ec3
JH
2311 }
2312 else if (date == at_time) {
e5229042
SP
2313 if (get_sha1_hex(rec + 41, sha1))
2314 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2315 }
2316 else {
e5229042
SP
2317 if (get_sha1_hex(rec + 41, logged_sha1))
2318 die("Log %s is corrupt.", logfile);
a89fccd2 2319 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2320 warning("Log %s unexpectedly ended on %s.",
73013afd 2321 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2322 }
2323 }
dc49cd76 2324 munmap(log_mapped, mapsz);
d556fae2
SP
2325 return 0;
2326 }
e5229042 2327 lastrec = rec;
ab2a1a32
JH
2328 if (cnt > 0)
2329 cnt--;
d556fae2
SP
2330 }
2331
e5229042
SP
2332 rec = logdata;
2333 while (rec < logend && *rec != '>' && *rec != '\n')
2334 rec++;
2335 if (rec == logend || *rec == '\n')
d556fae2 2336 die("Log %s is corrupt.", logfile);
e5229042 2337 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2338 tz = strtoul(tz_c, NULL, 10);
2339 if (get_sha1_hex(logdata, sha1))
2340 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2341 if (is_null_sha1(sha1)) {
2342 if (get_sha1_hex(logdata + 41, sha1))
2343 die("Log %s is corrupt.", logfile);
2344 }
16d7cc90
JH
2345 if (msg)
2346 *msg = ref_msg(logdata, logend);
dc49cd76 2347 munmap(log_mapped, mapsz);
16d7cc90
JH
2348
2349 if (cutoff_time)
2350 *cutoff_time = date;
2351 if (cutoff_tz)
2352 *cutoff_tz = tz;
2353 if (cutoff_cnt)
2354 *cutoff_cnt = reccnt;
2355 return 1;
d556fae2 2356}
2ff81662 2357
dfefa935 2358int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
2359{
2360 const char *logfile;
2361 FILE *logfp;
8ca78803 2362 struct strbuf sb = STRBUF_INIT;
2266bf27 2363 int ret = 0;
2ff81662 2364
dfefa935 2365 logfile = git_path("logs/%s", refname);
2ff81662
JH
2366 logfp = fopen(logfile, "r");
2367 if (!logfp)
883d60fa 2368 return -1;
101d15e0
JH
2369
2370 if (ofs) {
2371 struct stat statbuf;
2372 if (fstat(fileno(logfp), &statbuf) ||
2373 statbuf.st_size < ofs ||
2374 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 2375 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 2376 fclose(logfp);
8ca78803 2377 strbuf_release(&sb);
101d15e0 2378 return -1;
9d33f7c2 2379 }
101d15e0
JH
2380 }
2381
8ca78803 2382 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 2383 unsigned char osha1[20], nsha1[20];
883d60fa
JS
2384 char *email_end, *message;
2385 unsigned long timestamp;
8ca78803 2386 int tz;
2ff81662
JH
2387
2388 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
2389 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2390 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2391 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2392 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
2393 email_end[1] != ' ' ||
2394 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2395 !message || message[0] != ' ' ||
2396 (message[1] != '+' && message[1] != '-') ||
2397 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2398 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2399 continue; /* corrupt? */
883d60fa
JS
2400 email_end[1] = '\0';
2401 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2402 if (message[6] != '\t')
2403 message += 6;
2404 else
2405 message += 7;
8ca78803
RS
2406 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2407 cb_data);
883d60fa 2408 if (ret)
2266bf27 2409 break;
2ff81662
JH
2410 }
2411 fclose(logfp);
8ca78803 2412 strbuf_release(&sb);
2266bf27 2413 return ret;
2ff81662 2414}
e29cb53a 2415
dfefa935 2416int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2417{
dfefa935 2418 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2419}
2420
989c0e5d
MH
2421/*
2422 * Call fn for each reflog in the namespace indicated by name. name
2423 * must be empty or end with '/'. Name will be used as a scratch
2424 * space, but its contents will be restored before return.
2425 */
2426static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 2427{
989c0e5d 2428 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 2429 int retval = 0;
93c603fc 2430 struct dirent *de;
989c0e5d 2431 int oldlen = name->len;
eb8381c8 2432
93c603fc 2433 if (!d)
989c0e5d 2434 return name->len ? errno : 0;
eb8381c8 2435
93c603fc
MH
2436 while ((de = readdir(d)) != NULL) {
2437 struct stat st;
eb8381c8 2438
93c603fc
MH
2439 if (de->d_name[0] == '.')
2440 continue;
93c603fc
MH
2441 if (has_extension(de->d_name, ".lock"))
2442 continue;
989c0e5d
MH
2443 strbuf_addstr(name, de->d_name);
2444 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2445 ; /* silently ignore */
93c603fc 2446 } else {
eb8381c8 2447 if (S_ISDIR(st.st_mode)) {
989c0e5d
MH
2448 strbuf_addch(name, '/');
2449 retval = do_for_each_reflog(name, fn, cb_data);
eb8381c8
NP
2450 } else {
2451 unsigned char sha1[20];
989c0e5d
MH
2452 if (read_ref_full(name->buf, sha1, 0, NULL))
2453 retval = error("bad ref for %s", name->buf);
eb8381c8 2454 else
989c0e5d 2455 retval = fn(name->buf, sha1, 0, cb_data);
eb8381c8
NP
2456 }
2457 if (retval)
2458 break;
2459 }
989c0e5d 2460 strbuf_setlen(name, oldlen);
eb8381c8 2461 }
93c603fc 2462 closedir(d);
eb8381c8
NP
2463 return retval;
2464}
2465
2466int for_each_reflog(each_ref_fn fn, void *cb_data)
2467{
989c0e5d
MH
2468 int retval;
2469 struct strbuf name;
2470 strbuf_init(&name, PATH_MAX);
2471 retval = do_for_each_reflog(&name, fn, cb_data);
2472 strbuf_release(&name);
2473 return retval;
eb8381c8 2474}
3d9f037c
CR
2475
2476int update_ref(const char *action, const char *refname,
2477 const unsigned char *sha1, const unsigned char *oldval,
2478 int flags, enum action_on_err onerr)
2479{
2480 static struct ref_lock *lock;
2481 lock = lock_any_ref_for_update(refname, oldval, flags);
2482 if (!lock) {
2483 const char *str = "Cannot lock the ref '%s'.";
2484 switch (onerr) {
2485 case MSG_ON_ERR: error(str, refname); break;
2486 case DIE_ON_ERR: die(str, refname); break;
2487 case QUIET_ON_ERR: break;
2488 }
2489 return 1;
2490 }
2491 if (write_ref_sha1(lock, sha1, action) < 0) {
2492 const char *str = "Cannot update the ref '%s'.";
2493 switch (onerr) {
2494 case MSG_ON_ERR: error(str, refname); break;
2495 case DIE_ON_ERR: die(str, refname); break;
2496 case QUIET_ON_ERR: break;
2497 }
2498 return 1;
2499 }
2500 return 0;
2501}
cda69f48 2502
5483f799 2503struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2504{
2505 for ( ; list; list = list->next)
2506 if (!strcmp(list->name, name))
5483f799 2507 return (struct ref *)list;
cda69f48
JK
2508 return NULL;
2509}
7c2b3029
JK
2510
2511/*
2512 * generate a format suitable for scanf from a ref_rev_parse_rules
2513 * rule, that is replace the "%.*s" spec with a "%s" spec
2514 */
2515static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2516{
2517 char *spec;
2518
2519 spec = strstr(rule, "%.*s");
2520 if (!spec || strstr(spec + 4, "%.*s"))
2521 die("invalid rule in ref_rev_parse_rules: %s", rule);
2522
2523 /* copy all until spec */
2524 strncpy(scanf_fmt, rule, spec - rule);
2525 scanf_fmt[spec - rule] = '\0';
2526 /* copy new spec */
2527 strcat(scanf_fmt, "%s");
2528 /* copy remaining rule */
2529 strcat(scanf_fmt, spec + 4);
2530
2531 return;
2532}
2533
dfefa935 2534char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2535{
2536 int i;
2537 static char **scanf_fmts;
2538 static int nr_rules;
2539 char *short_name;
2540
2541 /* pre generate scanf formats from ref_rev_parse_rules[] */
2542 if (!nr_rules) {
2543 size_t total_len = 0;
2544
2545 /* the rule list is NULL terminated, count them first */
2546 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2547 /* no +1 because strlen("%s") < strlen("%.*s") */
2548 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2549
2550 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2551
2552 total_len = 0;
2553 for (i = 0; i < nr_rules; i++) {
2554 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2555 + total_len;
2556 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2557 total_len += strlen(ref_rev_parse_rules[i]);
2558 }
2559 }
2560
2561 /* bail out if there are no rules */
2562 if (!nr_rules)
dfefa935 2563 return xstrdup(refname);
7c2b3029 2564
dfefa935
MH
2565 /* buffer for scanf result, at most refname must fit */
2566 short_name = xstrdup(refname);
7c2b3029
JK
2567
2568 /* skip first rule, it will always match */
2569 for (i = nr_rules - 1; i > 0 ; --i) {
2570 int j;
6e7b3309 2571 int rules_to_fail = i;
7c2b3029
JK
2572 int short_name_len;
2573
dfefa935 2574 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2575 continue;
2576
2577 short_name_len = strlen(short_name);
2578
6e7b3309
BW
2579 /*
2580 * in strict mode, all (except the matched one) rules
2581 * must fail to resolve to a valid non-ambiguous ref
2582 */
2583 if (strict)
2584 rules_to_fail = nr_rules;
2585
7c2b3029
JK
2586 /*
2587 * check if the short name resolves to a valid ref,
2588 * but use only rules prior to the matched one
2589 */
6e7b3309 2590 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2591 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2592 char refname[PATH_MAX];
2593
6e7b3309
BW
2594 /* skip matched rule */
2595 if (i == j)
2596 continue;
2597
7c2b3029
JK
2598 /*
2599 * the short name is ambiguous, if it resolves
2600 * (with this previous rule) to a valid ref
2601 * read_ref() returns 0 on success
2602 */
2603 mksnpath(refname, sizeof(refname),
2604 rule, short_name_len, short_name);
c6893323 2605 if (ref_exists(refname))
7c2b3029
JK
2606 break;
2607 }
2608
2609 /*
2610 * short name is non-ambiguous if all previous rules
2611 * haven't resolved to a valid ref
2612 */
6e7b3309 2613 if (j == rules_to_fail)
7c2b3029
JK
2614 return short_name;
2615 }
2616
2617 free(short_name);
dfefa935 2618 return xstrdup(refname);
7c2b3029 2619}