refs: document flags constants 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
MH
110struct ref_value {
111 unsigned char sha1[20];
112 unsigned char peeled[20];
113};
114
f006c42a
MH
115struct ref_cache;
116
28e6a34e
MH
117/*
118 * Information used (along with the information in ref_entry) to
119 * describe a level in the hierarchy of references. This data
120 * structure only occurs embedded in a union in struct ref_entry, and
121 * only when (ref_entry.flag & REF_DIR) is set. In that case,
122 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
123 * in the directory have already been read:
124 *
125 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
126 * or packed references, already read.
127 *
128 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
129 * references that hasn't been read yet (nor has any of its
130 * subdirectories).
131 *
132 * Entries within a directory are stored within a growable array of
133 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
134 * sorted are sorted by their component name in strcmp() order and the
135 * remaining entries are unsorted.
136 *
137 * Loose references are read lazily, one directory at a time. When a
138 * directory of loose references is read, then all of the references
139 * in that directory are stored, and REF_INCOMPLETE stubs are created
140 * for any subdirectories, but the subdirectories themselves are not
141 * read. The reading is triggered by get_ref_dir().
142 */
d3177275 143struct ref_dir {
e9c4c111 144 int nr, alloc;
e6ed3ca6
MH
145
146 /*
147 * Entries with index 0 <= i < sorted are sorted by name. New
148 * entries are appended to the list unsorted, and are sorted
149 * only when required; thus we avoid the need to sort the list
150 * after the addition of every reference.
151 */
152 int sorted;
153
f006c42a
MH
154 /* A pointer to the ref_cache that contains this ref_dir. */
155 struct ref_cache *ref_cache;
156
d3177275 157 struct ref_entry **entries;
e9c4c111
JP
158};
159
89df9c84
MH
160/*
161 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01,
162 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see
163 * refs.h.
164 */
165
166/*
167 * The field ref_entry->u.value.peeled of this value entry contains
168 * the correct peeled value for the reference, which might be
169 * null_sha1 if the reference is not a tag or if it is broken.
170 */
432ad41e 171#define REF_KNOWS_PEELED 0x08
28e6a34e
MH
172
173/* ref_entry represents a directory of references */
432ad41e 174#define REF_DIR 0x10
cf0adba7 175
28e6a34e
MH
176/*
177 * Entry has not yet been read from disk (used only for REF_DIR
178 * entries representing loose references)
179 */
180#define REF_INCOMPLETE 0x20
181
432ad41e
MH
182/*
183 * A ref_entry represents either a reference or a "subdirectory" of
28e6a34e
MH
184 * references.
185 *
186 * Each directory in the reference namespace is represented by a
187 * ref_entry with (flags & REF_DIR) set and containing a subdir member
188 * that holds the entries in that directory that have been read so
189 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
190 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
191 * used for loose reference directories.
192 *
193 * References are represented by a ref_entry with (flags & REF_DIR)
194 * unset and a value member that describes the reference's value. The
195 * flag member is at the ref_entry level, but it is also needed to
196 * interpret the contents of the value field (in other words, a
197 * ref_value object is not very much use without the enclosing
198 * ref_entry).
432ad41e
MH
199 *
200 * Reference names cannot end with slash and directories' names are
201 * always stored with a trailing slash (except for the top-level
202 * directory, which is always denoted by ""). This has two nice
203 * consequences: (1) when the entries in each subdir are sorted
204 * lexicographically by name (as they usually are), the references in
205 * a whole tree can be generated in lexicographic order by traversing
206 * the tree in left-to-right, depth-first order; (2) the names of
207 * references and subdirectories cannot conflict, and therefore the
208 * presence of an empty subdirectory does not block the creation of a
209 * similarly-named reference. (The fact that reference names with the
210 * same leading components can conflict *with each other* is a
211 * separate issue that is regulated by is_refname_available().)
212 *
213 * Please note that the name field contains the fully-qualified
214 * reference (or subdirectory) name. Space could be saved by only
215 * storing the relative names. But that would require the full names
216 * to be generated on the fly when iterating in do_for_each_ref(), and
217 * would break callback functions, who have always been able to assume
218 * that the name strings that they are passed will not be freed during
219 * the iteration.
220 */
bc5fd6d3
MH
221struct ref_entry {
222 unsigned char flag; /* ISSYMREF? ISPACKED? */
593f1bb8 223 union {
432ad41e
MH
224 struct ref_value value; /* if not (flags&REF_DIR) */
225 struct ref_dir subdir; /* if (flags&REF_DIR) */
593f1bb8 226 } u;
432ad41e
MH
227 /*
228 * The full name of the reference (e.g., "refs/heads/master")
229 * or the full name of the directory with a trailing slash
230 * (e.g., "refs/heads/"):
231 */
bc5fd6d3
MH
232 char name[FLEX_ARRAY];
233};
e1e22e37 234
28e6a34e
MH
235static void read_loose_refs(const char *dirname, struct ref_dir *dir);
236
d7826d54
MH
237static struct ref_dir *get_ref_dir(struct ref_entry *entry)
238{
28e6a34e 239 struct ref_dir *dir;
d7826d54 240 assert(entry->flag & REF_DIR);
28e6a34e
MH
241 dir = &entry->u.subdir;
242 if (entry->flag & REF_INCOMPLETE) {
243 read_loose_refs(entry->name, dir);
244 entry->flag &= ~REF_INCOMPLETE;
245 }
246 return dir;
d7826d54
MH
247}
248
cddc4258
MH
249static struct ref_entry *create_ref_entry(const char *refname,
250 const unsigned char *sha1, int flag,
251 int check_name)
e1e22e37
LT
252{
253 int len;
cddc4258 254 struct ref_entry *ref;
e1e22e37 255
09116a1c 256 if (check_name &&
dfefa935
MH
257 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
258 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
259 len = strlen(refname) + 1;
260 ref = xmalloc(sizeof(struct ref_entry) + len);
593f1bb8
MH
261 hashcpy(ref->u.value.sha1, sha1);
262 hashclr(ref->u.value.peeled);
cddc4258
MH
263 memcpy(ref->name, refname, len);
264 ref->flag = flag;
265 return ref;
266}
267
432ad41e
MH
268static void clear_ref_dir(struct ref_dir *dir);
269
732134ed
MH
270static void free_ref_entry(struct ref_entry *entry)
271{
27b5587c
MH
272 if (entry->flag & REF_DIR) {
273 /*
274 * Do not use get_ref_dir() here, as that might
275 * trigger the reading of loose refs.
276 */
277 clear_ref_dir(&entry->u.subdir);
278 }
732134ed
MH
279 free(entry);
280}
281
432ad41e
MH
282/*
283 * Add a ref_entry to the end of dir (unsorted). Entry is always
284 * stored directly in dir; no recursion into subdirectories is
285 * done.
286 */
287static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
cddc4258 288{
432ad41e
MH
289 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
290 dir->entries[dir->nr++] = entry;
654ad400
MH
291 /* optimize for the case that entries are added in order */
292 if (dir->nr == 1 ||
293 (dir->nr == dir->sorted + 1 &&
294 strcmp(dir->entries[dir->nr - 2]->name,
295 dir->entries[dir->nr - 1]->name) < 0))
296 dir->sorted = dir->nr;
c774aab9
JP
297}
298
432ad41e
MH
299/*
300 * Clear and free all entries in dir, recursively.
301 */
d3177275 302static void clear_ref_dir(struct ref_dir *dir)
bc5fd6d3
MH
303{
304 int i;
d3177275
MH
305 for (i = 0; i < dir->nr; i++)
306 free_ref_entry(dir->entries[i]);
307 free(dir->entries);
308 dir->sorted = dir->nr = dir->alloc = 0;
309 dir->entries = NULL;
bc5fd6d3
MH
310}
311
432ad41e
MH
312/*
313 * Create a struct ref_entry object for the specified dirname.
314 * dirname is the name of the directory with a trailing slash (e.g.,
315 * "refs/heads/") or "" for the top-level directory.
316 */
f006c42a 317static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
b9146f51
RS
318 const char *dirname, size_t len,
319 int incomplete)
432ad41e
MH
320{
321 struct ref_entry *direntry;
432ad41e 322 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
b9146f51
RS
323 memcpy(direntry->name, dirname, len);
324 direntry->name[len] = '\0';
f006c42a 325 direntry->u.subdir.ref_cache = ref_cache;
28e6a34e 326 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
432ad41e
MH
327 return direntry;
328}
329
e9c4c111 330static int ref_entry_cmp(const void *a, const void *b)
c774aab9 331{
e9c4c111
JP
332 struct ref_entry *one = *(struct ref_entry **)a;
333 struct ref_entry *two = *(struct ref_entry **)b;
334 return strcmp(one->name, two->name);
335}
c774aab9 336
d3177275 337static void sort_ref_dir(struct ref_dir *dir);
bc5fd6d3 338
e1980c9d
JH
339struct string_slice {
340 size_t len;
341 const char *str;
342};
343
344static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
345{
346 struct string_slice *key = (struct string_slice *)key_;
347 struct ref_entry *ent = *(struct ref_entry **)ent_;
348 int entlen = strlen(ent->name);
349 int cmplen = key->len < entlen ? key->len : entlen;
350 int cmp = memcmp(key->str, ent->name, cmplen);
351 if (cmp)
352 return cmp;
353 return key->len - entlen;
354}
355
432ad41e
MH
356/*
357 * Return the entry with the given refname from the ref_dir
358 * (non-recursively), sorting dir if necessary. Return NULL if no
28e6a34e 359 * such entry is found. dir must already be complete.
432ad41e 360 */
40ad937d
RS
361static struct ref_entry *search_ref_dir(struct ref_dir *dir,
362 const char *refname, size_t len)
bc5fd6d3 363{
e1980c9d
JH
364 struct ref_entry **r;
365 struct string_slice key;
bc5fd6d3 366
432ad41e 367 if (refname == NULL || !dir->nr)
bc5fd6d3
MH
368 return NULL;
369
d3177275 370 sort_ref_dir(dir);
e1980c9d
JH
371 key.len = len;
372 key.str = refname;
373 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
374 ref_entry_cmp_sslice);
bc5fd6d3
MH
375
376 if (r == NULL)
377 return NULL;
378
379 return *r;
380}
381
f348ac92
MH
382/*
383 * Search for a directory entry directly within dir (without
384 * recursing). Sort dir if necessary. subdirname must be a directory
385 * name (i.e., end in '/'). If mkdir is set, then create the
386 * directory if it is missing; otherwise, return NULL if the desired
28e6a34e 387 * directory cannot be found. dir must already be complete.
f348ac92 388 */
3f3aa1bc 389static struct ref_dir *search_for_subdir(struct ref_dir *dir,
dd02e728
RS
390 const char *subdirname, size_t len,
391 int mkdir)
f348ac92 392{
40ad937d 393 struct ref_entry *entry = search_ref_dir(dir, subdirname, len);
f348ac92
MH
394 if (!entry) {
395 if (!mkdir)
396 return NULL;
28e6a34e
MH
397 /*
398 * Since dir is complete, the absence of a subdir
399 * means that the subdir really doesn't exist;
400 * therefore, create an empty record for it but mark
401 * the record complete.
402 */
b9146f51 403 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
f348ac92
MH
404 add_entry_to_dir(dir, entry);
405 }
3f3aa1bc 406 return get_ref_dir(entry);
f348ac92
MH
407}
408
432ad41e
MH
409/*
410 * If refname is a reference name, find the ref_dir within the dir
411 * tree that should hold refname. If refname is a directory name
412 * (i.e., ends in '/'), then return that ref_dir itself. dir must
28e6a34e
MH
413 * represent the top-level directory and must already be complete.
414 * Sort ref_dirs and recurse into subdirectories as necessary. If
415 * mkdir is set, then create any missing directories; otherwise,
416 * return NULL if the desired directory cannot be found.
432ad41e
MH
417 */
418static struct ref_dir *find_containing_dir(struct ref_dir *dir,
419 const char *refname, int mkdir)
420{
5fa04418 421 const char *slash;
5fa04418 422 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
dd02e728 423 size_t dirnamelen = slash - refname + 1;
3f3aa1bc 424 struct ref_dir *subdir;
dd02e728 425 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
663c1295
JH
426 if (!subdir) {
427 dir = NULL;
f348ac92 428 break;
432ad41e 429 }
3f3aa1bc 430 dir = subdir;
432ad41e
MH
431 }
432
432ad41e
MH
433 return dir;
434}
435
436/*
437 * Find the value entry with the given name in dir, sorting ref_dirs
438 * and recursing into subdirectories as necessary. If the name is not
439 * found or it corresponds to a directory entry, return NULL.
440 */
441static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
442{
443 struct ref_entry *entry;
444 dir = find_containing_dir(dir, refname, 0);
445 if (!dir)
446 return NULL;
40ad937d 447 entry = search_ref_dir(dir, refname, strlen(refname));
432ad41e
MH
448 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
449}
450
451/*
452 * Add a ref_entry to the ref_dir (unsorted), recursing into
453 * subdirectories as necessary. dir must represent the top-level
454 * directory. Return 0 on success.
455 */
456static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
457{
458 dir = find_containing_dir(dir, ref->name, 1);
459 if (!dir)
460 return -1;
461 add_entry_to_dir(dir, ref);
462 return 0;
463}
464
202a56a9
MH
465/*
466 * Emit a warning and return true iff ref1 and ref2 have the same name
467 * and the same sha1. Die if they have the same name but different
468 * sha1s.
469 */
470static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
471{
432ad41e 472 if (strcmp(ref1->name, ref2->name))
202a56a9 473 return 0;
432ad41e
MH
474
475 /* Duplicate name; make sure that they don't conflict: */
476
477 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
478 /* This is impossible by construction */
479 die("Reference directory conflict: %s", ref1->name);
480
481 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
482 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
483
484 warning("Duplicated ref: %s", ref1->name);
485 return 1;
202a56a9
MH
486}
487
e6ed3ca6 488/*
432ad41e
MH
489 * Sort the entries in dir non-recursively (if they are not already
490 * sorted) and remove any duplicate entries.
e6ed3ca6 491 */
d3177275 492static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 493{
202a56a9 494 int i, j;
81a79d8e 495 struct ref_entry *last = NULL;
c774aab9 496
e6ed3ca6
MH
497 /*
498 * This check also prevents passing a zero-length array to qsort(),
499 * which is a problem on some platforms.
500 */
d3177275 501 if (dir->sorted == dir->nr)
e9c4c111 502 return;
c774aab9 503
d3177275 504 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 505
81a79d8e
MH
506 /* Remove any duplicates: */
507 for (i = 0, j = 0; j < dir->nr; j++) {
508 struct ref_entry *entry = dir->entries[j];
509 if (last && is_dup_ref(last, entry))
510 free_ref_entry(entry);
511 else
512 last = dir->entries[i++] = entry;
e9c4c111 513 }
81a79d8e 514 dir->sorted = dir->nr = i;
e9c4c111 515}
c774aab9 516
bc5fd6d3 517#define DO_FOR_EACH_INCLUDE_BROKEN 01
c774aab9 518
bc5fd6d3 519static struct ref_entry *current_ref;
c774aab9 520
bc5fd6d3
MH
521static int do_one_ref(const char *base, each_ref_fn fn, int trim,
522 int flags, void *cb_data, struct ref_entry *entry)
523{
429213e4 524 int retval;
bc5fd6d3
MH
525 if (prefixcmp(entry->name, base))
526 return 0;
c774aab9 527
bc5fd6d3
MH
528 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
529 if (entry->flag & REF_ISBROKEN)
530 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 531 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
532 error("%s does not point to a valid object!", entry->name);
533 return 0;
534 }
535 }
536 current_ref = entry;
593f1bb8 537 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
538 current_ref = NULL;
539 return retval;
bc5fd6d3 540}
c774aab9 541
c36b5bc2 542/*
d3177275 543 * Call fn for each reference in dir that has index in the range
432ad41e
MH
544 * offset <= index < dir->nr. Recurse into subdirectories that are in
545 * that index range, sorting them before iterating. This function
546 * does not sort dir itself; it should be sorted beforehand.
c36b5bc2 547 */
d3177275
MH
548static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
549 const char *base,
550 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
551{
552 int i;
d3177275
MH
553 assert(dir->sorted == dir->nr);
554 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
555 struct ref_entry *entry = dir->entries[i];
556 int retval;
557 if (entry->flag & REF_DIR) {
d7826d54
MH
558 struct ref_dir *subdir = get_ref_dir(entry);
559 sort_ref_dir(subdir);
560 retval = do_for_each_ref_in_dir(subdir, 0,
432ad41e
MH
561 base, fn, trim, flags, cb_data);
562 } else {
563 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
564 }
c36b5bc2
MH
565 if (retval)
566 return retval;
567 }
568 return 0;
569}
570
b3fd060f 571/*
d3177275 572 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
573 * by refname. Recurse into subdirectories. If a value entry appears
574 * in both dir1 and dir2, then only process the version that is in
575 * dir2. The input dirs must already be sorted, but subdirs will be
576 * sorted as needed.
b3fd060f 577 */
d3177275
MH
578static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
579 struct ref_dir *dir2,
580 const char *base, each_ref_fn fn, int trim,
581 int flags, void *cb_data)
b3fd060f
MH
582{
583 int retval;
584 int i1 = 0, i2 = 0;
585
d3177275
MH
586 assert(dir1->sorted == dir1->nr);
587 assert(dir2->sorted == dir2->nr);
432ad41e
MH
588 while (1) {
589 struct ref_entry *e1, *e2;
590 int cmp;
591 if (i1 == dir1->nr) {
592 return do_for_each_ref_in_dir(dir2, i2,
593 base, fn, trim, flags, cb_data);
594 }
595 if (i2 == dir2->nr) {
596 return do_for_each_ref_in_dir(dir1, i1,
597 base, fn, trim, flags, cb_data);
598 }
599 e1 = dir1->entries[i1];
600 e2 = dir2->entries[i2];
601 cmp = strcmp(e1->name, e2->name);
602 if (cmp == 0) {
603 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
604 /* Both are directories; descend them in parallel. */
d7826d54
MH
605 struct ref_dir *subdir1 = get_ref_dir(e1);
606 struct ref_dir *subdir2 = get_ref_dir(e2);
607 sort_ref_dir(subdir1);
608 sort_ref_dir(subdir2);
432ad41e 609 retval = do_for_each_ref_in_dirs(
d7826d54 610 subdir1, subdir2,
432ad41e
MH
611 base, fn, trim, flags, cb_data);
612 i1++;
613 i2++;
614 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
615 /* Both are references; ignore the one from dir1. */
616 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
617 i1++;
618 i2++;
619 } else {
620 die("conflict between reference and directory: %s",
621 e1->name);
622 }
b3fd060f 623 } else {
432ad41e
MH
624 struct ref_entry *e;
625 if (cmp < 0) {
626 e = e1;
b3fd060f 627 i1++;
432ad41e
MH
628 } else {
629 e = e2;
630 i2++;
631 }
632 if (e->flag & REF_DIR) {
d7826d54
MH
633 struct ref_dir *subdir = get_ref_dir(e);
634 sort_ref_dir(subdir);
432ad41e 635 retval = do_for_each_ref_in_dir(
d7826d54 636 subdir, 0,
432ad41e
MH
637 base, fn, trim, flags, cb_data);
638 } else {
639 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
b3fd060f
MH
640 }
641 }
642 if (retval)
643 return retval;
644 }
d3177275
MH
645 if (i1 < dir1->nr)
646 return do_for_each_ref_in_dir(dir1, i1,
647 base, fn, trim, flags, cb_data);
648 if (i2 < dir2->nr)
649 return do_for_each_ref_in_dir(dir2, i2,
650 base, fn, trim, flags, cb_data);
b3fd060f
MH
651 return 0;
652}
653
d66da478
MH
654/*
655 * Return true iff refname1 and refname2 conflict with each other.
656 * Two reference names conflict if one of them exactly matches the
657 * leading components of the other; e.g., "foo/bar" conflicts with
658 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
659 * "foo/barbados".
660 */
661static int names_conflict(const char *refname1, const char *refname2)
662{
5a4d4947
MH
663 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
664 ;
665 return (*refname1 == '\0' && *refname2 == '/')
666 || (*refname1 == '/' && *refname2 == '\0');
667}
668
669struct name_conflict_cb {
670 const char *refname;
671 const char *oldrefname;
672 const char *conflicting_refname;
673};
674
675static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
676 int flags, void *cb_data)
677{
678 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
679 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
680 return 0;
681 if (names_conflict(data->refname, existingrefname)) {
682 data->conflicting_refname = existingrefname;
683 return 1;
d66da478 684 }
5a4d4947 685 return 0;
d66da478
MH
686}
687
bc5fd6d3
MH
688/*
689 * Return true iff a reference named refname could be created without
5a4d4947
MH
690 * conflicting with the name of an existing reference in array. If
691 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
692 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
693 * operation).
694 */
695static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 696 struct ref_dir *dir)
bc5fd6d3 697{
5a4d4947
MH
698 struct name_conflict_cb data;
699 data.refname = refname;
700 data.oldrefname = oldrefname;
701 data.conflicting_refname = NULL;
702
d3177275
MH
703 sort_ref_dir(dir);
704 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
705 0, DO_FOR_EACH_INCLUDE_BROKEN,
706 &data)) {
5a4d4947
MH
707 error("'%s' exists; cannot create '%s'",
708 data.conflicting_refname, refname);
709 return 0;
bc5fd6d3
MH
710 }
711 return 1;
e1e22e37
LT
712}
713
5e290ff7
JH
714/*
715 * Future: need to be in "struct repository"
716 * when doing a full libification.
717 */
79c7ca54
MH
718static struct ref_cache {
719 struct ref_cache *next;
d12229f5
MH
720 struct ref_entry *loose;
721 struct ref_entry *packed;
ce40979c
MH
722 /* The submodule name, or "" for the main repo. */
723 char name[FLEX_ARRAY];
79c7ca54 724} *ref_cache;
0e88c130 725
760c4512 726static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 727{
d12229f5
MH
728 if (refs->packed) {
729 free_ref_entry(refs->packed);
730 refs->packed = NULL;
731 }
5e290ff7 732}
e1e22e37 733
760c4512
MH
734static void clear_loose_ref_cache(struct ref_cache *refs)
735{
d12229f5
MH
736 if (refs->loose) {
737 free_ref_entry(refs->loose);
738 refs->loose = NULL;
739 }
760c4512
MH
740}
741
79c7ca54 742static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 743{
ce40979c 744 int len;
79c7ca54 745 struct ref_cache *refs;
ce40979c
MH
746 if (!submodule)
747 submodule = "";
748 len = strlen(submodule) + 1;
79c7ca54 749 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 750 memcpy(refs->name, submodule, len);
e5dbf605
MH
751 return refs;
752}
753
4349a668 754/*
79c7ca54 755 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
756 * the main repository, use submodule==NULL. The returned structure
757 * will be allocated and initialized but not necessarily populated; it
758 * should not be freed.
759 */
79c7ca54 760static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 761{
79c7ca54 762 struct ref_cache *refs = ref_cache;
0e88c130
MH
763 if (!submodule)
764 submodule = "";
765 while (refs) {
766 if (!strcmp(submodule, refs->name))
767 return refs;
768 refs = refs->next;
4349a668 769 }
0e88c130 770
79c7ca54
MH
771 refs = create_ref_cache(submodule);
772 refs->next = ref_cache;
773 ref_cache = refs;
0e88c130 774 return refs;
4349a668
MH
775}
776
8be8bde7 777void invalidate_ref_cache(const char *submodule)
f130b116 778{
c5f29abd
MH
779 struct ref_cache *refs = get_ref_cache(submodule);
780 clear_packed_ref_cache(refs);
781 clear_loose_ref_cache(refs);
5e290ff7 782}
e1e22e37 783
bc5fd6d3
MH
784/*
785 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
786 * Return a pointer to the refname within the line (null-terminated),
787 * or NULL if there was a problem.
788 */
789static const char *parse_ref_line(char *line, unsigned char *sha1)
790{
791 /*
792 * 42: the answer to everything.
793 *
794 * In this case, it happens to be the answer to
795 * 40 (length of sha1 hex representation)
796 * +1 (space in between hex and name)
797 * +1 (newline at the end of the line)
798 */
799 int len = strlen(line) - 42;
800
801 if (len <= 0)
802 return NULL;
803 if (get_sha1_hex(line, sha1) < 0)
804 return NULL;
805 if (!isspace(line[40]))
806 return NULL;
807 line += 41;
808 if (isspace(*line))
809 return NULL;
810 if (line[len] != '\n')
811 return NULL;
812 line[len] = 0;
813
814 return line;
815}
816
c29c46fa
MH
817/*
818 * Read f, which is a packed-refs file, into dir.
819 *
820 * A comment line of the form "# pack-refs with: " may contain zero or
821 * more traits. We interpret the traits as follows:
822 *
823 * No traits:
824 *
825 * Probably no references are peeled. But if the file contains a
826 * peeled value for a reference, we will use it.
827 *
828 * peeled:
829 *
830 * References under "refs/tags/", if they *can* be peeled, *are*
831 * peeled in this file. References outside of "refs/tags/" are
832 * probably not peeled even if they could have been, but if we find
833 * a peeled value for such a reference we will use it.
834 *
835 * fully-peeled:
836 *
837 * All references in the file that can be peeled are peeled.
838 * Inversely (and this is more important), any references in the
839 * file for which no peeled value is recorded is not peelable. This
840 * trait should typically be written alongside "peeled" for
841 * compatibility with older clients, but we do not require it
842 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
843 */
d3177275 844static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 845{
e9c4c111 846 struct ref_entry *last = NULL;
f4204ab9 847 char refline[PATH_MAX];
c29c46fa 848 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
f4204ab9
JH
849
850 while (fgets(refline, sizeof(refline), f)) {
851 unsigned char sha1[20];
dfefa935 852 const char *refname;
f4204ab9
JH
853 static const char header[] = "# pack-refs with:";
854
855 if (!strncmp(refline, header, sizeof(header)-1)) {
856 const char *traits = refline + sizeof(header) - 1;
c29c46fa
MH
857 if (strstr(traits, " fully-peeled "))
858 peeled = PEELED_FULLY;
859 else if (strstr(traits, " peeled "))
860 peeled = PEELED_TAGS;
f4204ab9
JH
861 /* perhaps other traits later as well */
862 continue;
863 }
864
dfefa935
MH
865 refname = parse_ref_line(refline, sha1);
866 if (refname) {
c29c46fa
MH
867 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
868 if (peeled == PEELED_FULLY ||
869 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
870 last->flag |= REF_KNOWS_PEELED;
d3177275 871 add_ref(dir, last);
f4204ab9
JH
872 continue;
873 }
874 if (last &&
875 refline[0] == '^' &&
876 strlen(refline) == 42 &&
877 refline[41] == '\n' &&
c29c46fa 878 !get_sha1_hex(refline + 1, sha1)) {
593f1bb8 879 hashcpy(last->u.value.peeled, sha1);
c29c46fa
MH
880 /*
881 * Regardless of what the file header said,
882 * we definitely know the value of *this*
883 * reference:
884 */
885 last->flag |= REF_KNOWS_PEELED;
886 }
f4204ab9 887 }
f4204ab9
JH
888}
889
d3177275 890static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 891{
d12229f5 892 if (!refs->packed) {
4349a668
MH
893 const char *packed_refs_file;
894 FILE *f;
0bad611b 895
b9146f51 896 refs->packed = create_dir_entry(refs, "", 0, 0);
316b097a
MH
897 if (*refs->name)
898 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
899 else
900 packed_refs_file = git_path("packed-refs");
901 f = fopen(packed_refs_file, "r");
e1e22e37 902 if (f) {
d7826d54 903 read_packed_refs(f, get_ref_dir(refs->packed));
e1e22e37 904 fclose(f);
e1e22e37 905 }
e1e22e37 906 }
d7826d54 907 return get_ref_dir(refs->packed);
e1e22e37
LT
908}
909
30249ee6
MH
910void add_packed_ref(const char *refname, const unsigned char *sha1)
911{
912 add_ref(get_packed_refs(get_ref_cache(NULL)),
913 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
914}
915
abc39098 916/*
28e6a34e
MH
917 * Read the loose references from the namespace dirname into dir
918 * (without recursing). dirname must end with '/'. dir must be the
919 * directory entry corresponding to dirname.
abc39098 920 */
423a1afc 921static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 922{
423a1afc 923 struct ref_cache *refs = dir->ref_cache;
d3177275 924 DIR *d;
0bad611b 925 const char *path;
d5fdae67 926 struct dirent *de;
abc39098 927 int dirnamelen = strlen(dirname);
72b64b44 928 struct strbuf refname;
0bad611b 929
3b124823 930 if (*refs->name)
66a3d20b 931 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 932 else
66a3d20b 933 path = git_path("%s", dirname);
0bad611b 934
d3177275 935 d = opendir(path);
d5fdae67
MH
936 if (!d)
937 return;
938
66a3d20b
MH
939 strbuf_init(&refname, dirnamelen + 257);
940 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
941
942 while ((de = readdir(d)) != NULL) {
943 unsigned char sha1[20];
944 struct stat st;
945 int flag;
d5fdae67
MH
946 const char *refdir;
947
948 if (de->d_name[0] == '.')
949 continue;
d5fdae67
MH
950 if (has_extension(de->d_name, ".lock"))
951 continue;
72b64b44 952 strbuf_addstr(&refname, de->d_name);
d5fdae67 953 refdir = *refs->name
72b64b44
MH
954 ? git_path_submodule(refs->name, "%s", refname.buf)
955 : git_path("%s", refname.buf);
956 if (stat(refdir, &st) < 0) {
957 ; /* silently ignore */
958 } else if (S_ISDIR(st.st_mode)) {
abc39098 959 strbuf_addch(&refname, '/');
28e6a34e 960 add_entry_to_dir(dir,
b9146f51
RS
961 create_dir_entry(refs, refname.buf,
962 refname.len, 1));
72b64b44 963 } else {
3b124823 964 if (*refs->name) {
f8948e2f 965 hashclr(sha1);
0bad611b 966 flag = 0;
72b64b44 967 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
0bad611b 968 hashclr(sha1);
98ac34b2 969 flag |= REF_ISBROKEN;
0bad611b 970 }
72b64b44 971 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
972 hashclr(sha1);
973 flag |= REF_ISBROKEN;
974 }
9f2fb4a3
MH
975 add_entry_to_dir(dir,
976 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 977 }
66a3d20b 978 strbuf_setlen(&refname, dirnamelen);
e1e22e37 979 }
72b64b44 980 strbuf_release(&refname);
d5fdae67 981 closedir(d);
e1e22e37
LT
982}
983
d3177275 984static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 985{
d12229f5 986 if (!refs->loose) {
28e6a34e
MH
987 /*
988 * Mark the top-level directory complete because we
989 * are about to read the only subdirectory that can
990 * hold references:
991 */
b9146f51 992 refs->loose = create_dir_entry(refs, "", 0, 0);
28e6a34e
MH
993 /*
994 * Create an incomplete entry for "refs/":
995 */
996 add_entry_to_dir(get_ref_dir(refs->loose),
b9146f51 997 create_dir_entry(refs, "refs/", 5, 1));
e1e22e37 998 }
d7826d54 999 return get_ref_dir(refs->loose);
e1e22e37
LT
1000}
1001
ca8db142
LT
1002/* We allow "recursive" symbolic refs. Only within reason, though */
1003#define MAXDEPTH 5
0ebde32c
LT
1004#define MAXREFLEN (1024)
1005
e5fa45c1
JH
1006/*
1007 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
1008 * from the loose refs in ref_cache refs. Find <refname> in the
1009 * packed-refs file for the submodule.
e5fa45c1 1010 */
b0626608 1011static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 1012 const char *refname, unsigned char *sha1)
0ebde32c 1013{
2c5c66be 1014 struct ref_entry *ref;
d3177275 1015 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 1016
432ad41e 1017 ref = find_ref(dir, refname);
b0626608
MH
1018 if (ref == NULL)
1019 return -1;
1020
593f1bb8 1021 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 1022 return 0;
0ebde32c
LT
1023}
1024
b0626608 1025static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 1026 const char *refname, unsigned char *sha1,
dfefa935 1027 int recursion)
0ebde32c 1028{
064d51dc 1029 int fd, len;
0ebde32c 1030 char buffer[128], *p;
064d51dc 1031 char *path;
0ebde32c 1032
064d51dc 1033 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 1034 return -1;
064d51dc
MH
1035 path = *refs->name
1036 ? git_path_submodule(refs->name, "%s", refname)
1037 : git_path("%s", refname);
1038 fd = open(path, O_RDONLY);
0ebde32c 1039 if (fd < 0)
b0626608 1040 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
1041
1042 len = read(fd, buffer, sizeof(buffer)-1);
1043 close(fd);
1044 if (len < 0)
1045 return -1;
1046 while (len && isspace(buffer[len-1]))
1047 len--;
1048 buffer[len] = 0;
1049
1050 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 1051 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
1052 return 0;
1053
1054 /* Symref? */
1055 if (strncmp(buffer, "ref:", 4))
1056 return -1;
1057 p = buffer + 4;
1058 while (isspace(*p))
1059 p++;
1060
064d51dc 1061 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
1062}
1063
85be1fe3 1064int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
1065{
1066 int len = strlen(path), retval;
064d51dc 1067 char *submodule;
b0626608 1068 struct ref_cache *refs;
0ebde32c
LT
1069
1070 while (len && path[len-1] == '/')
1071 len--;
1072 if (!len)
1073 return -1;
b0626608
MH
1074 submodule = xstrndup(path, len);
1075 refs = get_ref_cache(submodule);
1076 free(submodule);
1077
064d51dc 1078 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
1079 return retval;
1080}
ca8db142 1081
4886b89f 1082/*
c224ca7f
MH
1083 * Try to read ref from the packed references. On success, set sha1
1084 * and return 0; otherwise, return -1.
4886b89f 1085 */
dfefa935 1086static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 1087{
d3177275 1088 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
432ad41e 1089 struct ref_entry *entry = find_ref(packed, refname);
2c5c66be 1090 if (entry) {
593f1bb8 1091 hashcpy(sha1, entry->u.value.sha1);
2c5c66be 1092 return 0;
c224ca7f
MH
1093 }
1094 return -1;
1095}
1096
8d68493f 1097const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 1098{
0104ca09
HO
1099 int depth = MAXDEPTH;
1100 ssize_t len;
a876ed83 1101 char buffer[256];
dfefa935 1102 static char refname_buffer[256];
ca8db142 1103
8da19775
JH
1104 if (flag)
1105 *flag = 0;
1106
dfefa935 1107 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
1108 return NULL;
1109
a876ed83 1110 for (;;) {
55956350 1111 char path[PATH_MAX];
a876ed83
JH
1112 struct stat st;
1113 char *buf;
1114 int fd;
8a65ff76 1115
a876ed83
JH
1116 if (--depth < 0)
1117 return NULL;
ca8db142 1118
dfefa935 1119 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 1120
a876ed83 1121 if (lstat(path, &st) < 0) {
c224ca7f
MH
1122 if (errno != ENOENT)
1123 return NULL;
1124 /*
1125 * The loose reference file does not exist;
1126 * check for a packed reference.
1127 */
dfefa935 1128 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
1129 if (flag)
1130 *flag |= REF_ISPACKED;
dfefa935 1131 return refname;
434cd0cd 1132 }
c224ca7f
MH
1133 /* The reference is not a packed reference, either. */
1134 if (reading) {
a876ed83 1135 return NULL;
c224ca7f
MH
1136 } else {
1137 hashclr(sha1);
dfefa935 1138 return refname;
c224ca7f 1139 }
a876ed83 1140 }
ca8db142 1141
a876ed83
JH
1142 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1143 if (S_ISLNK(st.st_mode)) {
1144 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
1145 if (len < 0)
1146 return NULL;
b54cb795 1147 buffer[len] = 0;
1f58a038
MH
1148 if (!prefixcmp(buffer, "refs/") &&
1149 !check_refname_format(buffer, 0)) {
dfefa935
MH
1150 strcpy(refname_buffer, buffer);
1151 refname = refname_buffer;
8da19775
JH
1152 if (flag)
1153 *flag |= REF_ISSYMREF;
a876ed83
JH
1154 continue;
1155 }
ca8db142 1156 }
a876ed83 1157
7a21632f
DS
1158 /* Is it a directory? */
1159 if (S_ISDIR(st.st_mode)) {
1160 errno = EISDIR;
1161 return NULL;
1162 }
1163
a876ed83
JH
1164 /*
1165 * Anything else, just open it and try to use it as
1166 * a ref
1167 */
1168 fd = open(path, O_RDONLY);
1169 if (fd < 0)
1170 return NULL;
93d26e4c 1171 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1172 close(fd);
28775050
MH
1173 if (len < 0)
1174 return NULL;
1175 while (len && isspace(buffer[len-1]))
1176 len--;
1177 buffer[len] = '\0';
a876ed83
JH
1178
1179 /*
1180 * Is it a symbolic ref?
1181 */
28775050 1182 if (prefixcmp(buffer, "ref:"))
a876ed83 1183 break;
55956350
JH
1184 if (flag)
1185 *flag |= REF_ISSYMREF;
a876ed83 1186 buf = buffer + 4;
28775050
MH
1187 while (isspace(*buf))
1188 buf++;
313fb010 1189 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1190 if (flag)
1191 *flag |= REF_ISBROKEN;
313fb010
MH
1192 return NULL;
1193 }
dfefa935 1194 refname = strcpy(refname_buffer, buf);
8a65ff76 1195 }
f989fea0
MH
1196 /* Please note that FETCH_HEAD has a second line containing other data. */
1197 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1198 if (flag)
1199 *flag |= REF_ISBROKEN;
a876ed83 1200 return NULL;
629cd3ac 1201 }
dfefa935 1202 return refname;
a876ed83
JH
1203}
1204
96ec7b1e
NTND
1205char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1206{
8cad4744 1207 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1208 return ret ? xstrdup(ret) : NULL;
1209}
1210
d08bae7e
IL
1211/* The argument to filter_refs */
1212struct ref_filter {
1213 const char *pattern;
1214 each_ref_fn *fn;
1215 void *cb_data;
1216};
1217
dfefa935 1218int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1219{
8d68493f 1220 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1221 return 0;
1222 return -1;
8a65ff76
LT
1223}
1224
dfefa935 1225int read_ref(const char *refname, unsigned char *sha1)
c6893323 1226{
dfefa935 1227 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1228}
1229
bc5fd6d3 1230int ref_exists(const char *refname)
ef06b918 1231{
bc5fd6d3
MH
1232 unsigned char sha1[20];
1233 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1234}
1235
85be1fe3 1236static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1237 void *data)
d08bae7e
IL
1238{
1239 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1240 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1241 return 0;
85be1fe3 1242 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1243}
1244
dfefa935 1245int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1246{
1247 int flag;
1248 unsigned char base[20];
1249 struct object *o;
1250
dfefa935
MH
1251 if (current_ref && (current_ref->name == refname
1252 || !strcmp(current_ref->name, refname))) {
0ae91be0 1253 if (current_ref->flag & REF_KNOWS_PEELED) {
e6dbffa6
JK
1254 if (is_null_sha1(current_ref->u.value.peeled))
1255 return -1;
593f1bb8 1256 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
1257 return 0;
1258 }
593f1bb8 1259 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
1260 goto fallback;
1261 }
1262
dfefa935 1263 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1264 return -1;
1265
1266 if ((flag & REF_ISPACKED)) {
d3177275 1267 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
432ad41e 1268 struct ref_entry *r = find_ref(dir, refname);
cf0adba7 1269
e9c4c111 1270 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
593f1bb8 1271 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1272 return 0;
cf0adba7 1273 }
cf0adba7
JH
1274 }
1275
0ae91be0 1276fallback:
6c4a060d
JK
1277 o = lookup_unknown_object(base);
1278 if (o->type == OBJ_NONE) {
1279 int type = sha1_object_info(base, NULL);
1280 if (type < 0)
1281 return -1;
1282 o->type = type;
1283 }
1284
1285 if (o->type == OBJ_TAG) {
44da6f69 1286 o = deref_tag_noverify(o);
cf0adba7
JH
1287 if (o) {
1288 hashcpy(sha1, o->sha1);
1289 return 0;
1290 }
1291 }
1292 return -1;
1293}
1294
bc5fd6d3
MH
1295struct warn_if_dangling_data {
1296 FILE *fp;
1297 const char *refname;
1298 const char *msg_fmt;
1299};
1300
1301static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1302 int flags, void *cb_data)
1303{
1304 struct warn_if_dangling_data *d = cb_data;
1305 const char *resolves_to;
1306 unsigned char junk[20];
1307
1308 if (!(flags & REF_ISSYMREF))
1309 return 0;
1310
1311 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1312 if (!resolves_to || strcmp(resolves_to, d->refname))
1313 return 0;
1314
1315 fprintf(d->fp, d->msg_fmt, refname);
1be65eda 1316 fputc('\n', d->fp);
bc5fd6d3
MH
1317 return 0;
1318}
1319
1320void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1321{
1322 struct warn_if_dangling_data data;
1323
1324 data.fp = fp;
1325 data.refname = refname;
1326 data.msg_fmt = msg_fmt;
1327 for_each_rawref(warn_if_dangling_symref, &data);
1328}
1329
0bad611b
HV
1330static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1331 int trim, int flags, void *cb_data)
8a65ff76 1332{
316b097a 1333 struct ref_cache *refs = get_ref_cache(submodule);
933ac036
MH
1334 struct ref_dir *packed_dir = get_packed_refs(refs);
1335 struct ref_dir *loose_dir = get_loose_refs(refs);
1336 int retval = 0;
1337
1338 if (base && *base) {
1339 packed_dir = find_containing_dir(packed_dir, base, 0);
1340 loose_dir = find_containing_dir(loose_dir, base, 0);
1341 }
1342
1343 if (packed_dir && loose_dir) {
1344 sort_ref_dir(packed_dir);
1345 sort_ref_dir(loose_dir);
1346 retval = do_for_each_ref_in_dirs(
1347 packed_dir, loose_dir,
1348 base, fn, trim, flags, cb_data);
1349 } else if (packed_dir) {
1350 sort_ref_dir(packed_dir);
1351 retval = do_for_each_ref_in_dir(
1352 packed_dir, 0,
1353 base, fn, trim, flags, cb_data);
1354 } else if (loose_dir) {
1355 sort_ref_dir(loose_dir);
1356 retval = do_for_each_ref_in_dir(
1357 loose_dir, 0,
1358 base, fn, trim, flags, cb_data);
1359 }
1360
1361 return retval;
8a65ff76
LT
1362}
1363
0bad611b 1364static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1365{
1366 unsigned char sha1[20];
8da19775
JH
1367 int flag;
1368
0bad611b
HV
1369 if (submodule) {
1370 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1371 return fn("HEAD", sha1, 0, cb_data);
1372
1373 return 0;
1374 }
1375
c6893323 1376 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1377 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1378
2f34ba32 1379 return 0;
723c31fe
LT
1380}
1381
0bad611b
HV
1382int head_ref(each_ref_fn fn, void *cb_data)
1383{
1384 return do_head_ref(NULL, fn, cb_data);
1385}
1386
9ef6aeb0
HV
1387int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1388{
1389 return do_head_ref(submodule, fn, cb_data);
1390}
1391
cb5d709f 1392int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1393{
b3cfc406 1394 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1395}
1396
9ef6aeb0
HV
1397int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1398{
b3cfc406 1399 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1400}
1401
2a8177b6
CC
1402int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1403{
0bad611b 1404 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1405}
1406
9ef6aeb0
HV
1407int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1408 each_ref_fn fn, void *cb_data)
1409{
1410 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1411}
1412
cb5d709f 1413int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1414{
2a8177b6 1415 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1416}
1417
9ef6aeb0
HV
1418int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1419{
1420 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1421}
1422
cb5d709f 1423int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1424{
2a8177b6 1425 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1426}
1427
9ef6aeb0
HV
1428int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1429{
1430 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1431}
1432
cb5d709f 1433int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1434{
2a8177b6 1435 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1436}
1437
9ef6aeb0
HV
1438int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1439{
1440 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1441}
1442
29268700
CC
1443int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1444{
0bad611b 1445 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1446}
1447
a1bea2c1
JT
1448int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1449{
1450 struct strbuf buf = STRBUF_INIT;
1451 int ret = 0;
1452 unsigned char sha1[20];
1453 int flag;
1454
1455 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1456 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1457 ret = fn(buf.buf, sha1, flag, cb_data);
1458 strbuf_release(&buf);
1459
1460 return ret;
1461}
1462
1463int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1464{
1465 struct strbuf buf = STRBUF_INIT;
1466 int ret;
1467 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1468 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1469 strbuf_release(&buf);
1470 return ret;
1471}
1472
b09fe971
IL
1473int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1474 const char *prefix, void *cb_data)
d08bae7e
IL
1475{
1476 struct strbuf real_pattern = STRBUF_INIT;
1477 struct ref_filter filter;
d08bae7e
IL
1478 int ret;
1479
b09fe971 1480 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1481 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1482 else if (prefix)
1483 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1484 strbuf_addstr(&real_pattern, pattern);
1485
894a9d33 1486 if (!has_glob_specials(pattern)) {
9517e6b8 1487 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1488 if (real_pattern.buf[real_pattern.len - 1] != '/')
1489 strbuf_addch(&real_pattern, '/');
1490 /* No need to check for '*', there is none. */
1491 strbuf_addch(&real_pattern, '*');
1492 }
1493
1494 filter.pattern = real_pattern.buf;
1495 filter.fn = fn;
1496 filter.cb_data = cb_data;
1497 ret = for_each_ref(filter_refs, &filter);
1498
1499 strbuf_release(&real_pattern);
1500 return ret;
1501}
1502
b09fe971
IL
1503int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1504{
1505 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1506}
1507
f8948e2f
JH
1508int for_each_rawref(each_ref_fn fn, void *cb_data)
1509{
b3cfc406 1510 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1511 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1512}
1513
4577e483 1514const char *prettify_refname(const char *name)
a9c37a72 1515{
a9c37a72
DB
1516 return name + (
1517 !prefixcmp(name, "refs/heads/") ? 11 :
1518 !prefixcmp(name, "refs/tags/") ? 10 :
1519 !prefixcmp(name, "refs/remotes/") ? 13 :
1520 0);
1521}
1522
79803322
SP
1523const char *ref_rev_parse_rules[] = {
1524 "%.*s",
1525 "refs/%.*s",
1526 "refs/tags/%.*s",
1527 "refs/heads/%.*s",
1528 "refs/remotes/%.*s",
1529 "refs/remotes/%.*s/HEAD",
1530 NULL
1531};
1532
1533int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1534{
1535 const char **p;
1536 const int abbrev_name_len = strlen(abbrev_name);
1537
1538 for (p = rules; *p; p++) {
1539 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1540 return 1;
1541 }
1542 }
1543
1544 return 0;
1545}
1546
e5f38ec3 1547static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1548 const unsigned char *old_sha1, int mustexist)
1549{
c6893323 1550 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1551 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1552 unlock_ref(lock);
1553 return NULL;
1554 }
a89fccd2 1555 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1556 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1557 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1558 unlock_ref(lock);
1559 return NULL;
1560 }
1561 return lock;
1562}
1563
7155b727 1564static int remove_empty_directories(const char *file)
bc7127ef
JH
1565{
1566 /* we want to create a file but there is a directory there;
1567 * if that is an empty directory (or a directory that contains
1568 * only empty directories), remove them.
1569 */
7155b727
JS
1570 struct strbuf path;
1571 int result;
bc7127ef 1572
7155b727
JS
1573 strbuf_init(&path, 20);
1574 strbuf_addstr(&path, file);
1575
a0f4afbe 1576 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1577
1578 strbuf_release(&path);
1579
1580 return result;
bc7127ef
JH
1581}
1582
ff74f7f1
JH
1583/*
1584 * *string and *len will only be substituted, and *string returned (for
1585 * later free()ing) if the string passed in is a magic short-hand form
1586 * to name a branch.
1587 */
1588static char *substitute_branch_name(const char **string, int *len)
1589{
1590 struct strbuf buf = STRBUF_INIT;
1591 int ret = interpret_branch_name(*string, &buf);
1592
1593 if (ret == *len) {
1594 size_t size;
1595 *string = strbuf_detach(&buf, &size);
1596 *len = size;
1597 return (char *)*string;
1598 }
1599
1600 return NULL;
1601}
1602
1603int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1604{
1605 char *last_branch = substitute_branch_name(&str, &len);
1606 const char **p, *r;
1607 int refs_found = 0;
1608
1609 *ref = NULL;
1610 for (p = ref_rev_parse_rules; *p; p++) {
1611 char fullref[PATH_MAX];
1612 unsigned char sha1_from_ref[20];
1613 unsigned char *this_result;
1614 int flag;
1615
1616 this_result = refs_found ? sha1_from_ref : sha1;
1617 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1618 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1619 if (r) {
1620 if (!refs_found++)
1621 *ref = xstrdup(r);
1622 if (!warn_ambiguous_refs)
1623 break;
55956350 1624 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1625 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1626 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1627 warning("ignoring broken ref %s.", fullref);
1628 }
ff74f7f1
JH
1629 }
1630 free(last_branch);
1631 return refs_found;
1632}
1633
1634int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1635{
1636 char *last_branch = substitute_branch_name(&str, &len);
1637 const char **p;
1638 int logs_found = 0;
1639
1640 *log = NULL;
1641 for (p = ref_rev_parse_rules; *p; p++) {
1642 struct stat st;
1643 unsigned char hash[20];
1644 char path[PATH_MAX];
1645 const char *ref, *it;
1646
1647 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1648 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1649 if (!ref)
1650 continue;
1651 if (!stat(git_path("logs/%s", path), &st) &&
1652 S_ISREG(st.st_mode))
1653 it = path;
1654 else if (strcmp(ref, path) &&
1655 !stat(git_path("logs/%s", ref), &st) &&
1656 S_ISREG(st.st_mode))
1657 it = ref;
1658 else
1659 continue;
1660 if (!logs_found++) {
1661 *log = xstrdup(it);
1662 hashcpy(sha1, hash);
1663 }
1664 if (!warn_ambiguous_refs)
1665 break;
1666 }
1667 free(last_branch);
1668 return logs_found;
1669}
1670
dfefa935
MH
1671static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1672 const unsigned char *old_sha1,
1673 int flags, int *type_p)
4bd18c43 1674{
434cd0cd 1675 char *ref_file;
dfefa935 1676 const char *orig_refname = refname;
4bd18c43 1677 struct ref_lock *lock;
5cc3cef9 1678 int last_errno = 0;
acd3b9ec 1679 int type, lflags;
4431fcc4 1680 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1681 int missing = 0;
4bd18c43
SP
1682
1683 lock = xcalloc(1, sizeof(struct ref_lock));
1684 lock->lock_fd = -1;
1685
8d68493f 1686 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1687 if (!refname && errno == EISDIR) {
bc7127ef
JH
1688 /* we are trying to lock foo but we used to
1689 * have foo/bar which now does not exist;
1690 * it is normal for the empty directory 'foo'
1691 * to remain.
1692 */
dfefa935 1693 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1694 if (remove_empty_directories(ref_file)) {
1695 last_errno = errno;
dfefa935 1696 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1697 goto error_return;
1698 }
8d68493f 1699 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1700 }
68db31cc
SV
1701 if (type_p)
1702 *type_p = type;
dfefa935 1703 if (!refname) {
5cc3cef9 1704 last_errno = errno;
818f477c 1705 error("unable to resolve reference %s: %s",
dfefa935 1706 orig_refname, strerror(errno));
5cc3cef9 1707 goto error_return;
4bd18c43 1708 }
5bdd8d4a 1709 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1710 /* When the ref did not exist and we are creating it,
1711 * make sure there is no existing ref that is packed
1712 * whose name begins with our refname, nor a ref whose
1713 * name is a proper prefix of our refname.
1714 */
5bdd8d4a 1715 if (missing &&
316b097a 1716 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1717 last_errno = ENOTDIR;
c976d415 1718 goto error_return;
f475e08e 1719 }
22a3844e 1720
c33d5174 1721 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1722
acd3b9ec
JH
1723 lflags = LOCK_DIE_ON_ERROR;
1724 if (flags & REF_NODEREF) {
dfefa935 1725 refname = orig_refname;
acd3b9ec
JH
1726 lflags |= LOCK_NODEREF;
1727 }
dfefa935
MH
1728 lock->ref_name = xstrdup(refname);
1729 lock->orig_ref_name = xstrdup(orig_refname);
1730 ref_file = git_path("%s", refname);
5bdd8d4a 1731 if (missing)
68db31cc
SV
1732 lock->force_write = 1;
1733 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1734 lock->force_write = 1;
4bd18c43 1735
5cc3cef9
JH
1736 if (safe_create_leading_directories(ref_file)) {
1737 last_errno = errno;
1738 error("unable to create directory for %s", ref_file);
1739 goto error_return;
1740 }
4bd18c43 1741
acd3b9ec 1742 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1743 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1744
1745 error_return:
1746 unlock_ref(lock);
1747 errno = last_errno;
1748 return NULL;
4bd18c43
SP
1749}
1750
dfefa935 1751struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1752{
53cce84c 1753 char refpath[PATH_MAX];
dfefa935 1754 if (check_refname_format(refname, 0))
4bd18c43 1755 return NULL;
dfefa935 1756 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1757 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1758}
1759
dfefa935
MH
1760struct ref_lock *lock_any_ref_for_update(const char *refname,
1761 const unsigned char *old_sha1, int flags)
4bd18c43 1762{
dfefa935 1763 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1764 return NULL;
dfefa935 1765 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1766}
1767
d66da478
MH
1768struct repack_without_ref_sb {
1769 const char *refname;
1770 int fd;
1771};
1772
1773static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1774 int flags, void *cb_data)
1775{
1776 struct repack_without_ref_sb *data = cb_data;
1777 char line[PATH_MAX + 100];
1778 int len;
1779
1780 if (!strcmp(data->refname, refname))
1781 return 0;
1782 len = snprintf(line, sizeof(line), "%s %s\n",
1783 sha1_to_hex(sha1), refname);
1784 /* this should not happen but just being defensive */
1785 if (len > sizeof(line))
1786 die("too long a refname '%s'", refname);
1787 write_or_die(data->fd, line, len);
1788 return 0;
1789}
1790
26a063a1
JH
1791static struct lock_file packlock;
1792
c0277d15
JH
1793static int repack_without_ref(const char *refname)
1794{
d66da478 1795 struct repack_without_ref_sb data;
b3f1280e
JK
1796 struct ref_cache *refs = get_ref_cache(NULL);
1797 struct ref_dir *packed = get_packed_refs(refs);
432ad41e 1798 if (find_ref(packed, refname) == NULL)
c0277d15 1799 return 0;
d66da478
MH
1800 data.refname = refname;
1801 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1802 if (data.fd < 0) {
1b018fd9 1803 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1804 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1805 }
b3f1280e
JK
1806 clear_packed_ref_cache(refs);
1807 packed = get_packed_refs(refs);
d3177275 1808 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1809 return commit_lock_file(&packlock);
1810}
1811
eca35a25 1812int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1813{
1814 struct ref_lock *lock;
eca35a25 1815 int err, i = 0, ret = 0, flag = 0;
c0277d15 1816
547d058f 1817 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
c0277d15
JH
1818 if (!lock)
1819 return 1;
045a476f 1820 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1821 /* loose */
547d058f
RS
1822 i = strlen(lock->lk->filename) - 5; /* .lock */
1823 lock->lk->filename[i] = 0;
1824 err = unlink_or_warn(lock->lk->filename);
691f1a28 1825 if (err && errno != ENOENT)
c0277d15 1826 ret = 1;
691f1a28 1827
547d058f 1828 lock->lk->filename[i] = '.';
c0277d15
JH
1829 }
1830 /* removing the loose one could have resurrected an earlier
1831 * packed one. Also, if it was not loose we need to repack
1832 * without it.
1833 */
b274a714 1834 ret |= repack_without_ref(lock->ref_name);
c0277d15 1835
691f1a28 1836 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1837 invalidate_ref_cache(NULL);
c0277d15
JH
1838 unlock_ref(lock);
1839 return ret;
4bd18c43
SP
1840}
1841
765c2258
PH
1842/*
1843 * People using contrib's git-new-workdir have .git/logs/refs ->
1844 * /some/other/path/.git/logs/refs, and that may live on another device.
1845 *
1846 * IOW, to avoid cross device rename errors, the temporary renamed log must
1847 * live into logs/refs.
1848 */
1849#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1850
dfefa935 1851int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1852{
c976d415
LH
1853 unsigned char sha1[20], orig_sha1[20];
1854 int flag = 0, logmoved = 0;
1855 struct ref_lock *lock;
c976d415 1856 struct stat loginfo;
dfefa935 1857 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1858 const char *symref = NULL;
316b097a 1859 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1860
450d4c0f 1861 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1862 return error("reflog for %s is a symlink", oldrefname);
c976d415 1863
8d68493f 1864 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1865 if (flag & REF_ISSYMREF)
fa58186c 1866 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1867 oldrefname);
eca35a25 1868 if (!symref)
dfefa935 1869 return error("refname %s not found", oldrefname);
c976d415 1870
316b097a 1871 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1872 return 1;
1873
316b097a 1874 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1875 return 1;
1876
dfefa935 1877 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1878 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1879 oldrefname, strerror(errno));
c976d415 1880
dfefa935
MH
1881 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1882 error("unable to delete old %s", oldrefname);
c976d415
LH
1883 goto rollback;
1884 }
1885
dfefa935
MH
1886 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1887 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1888 if (errno==EISDIR) {
dfefa935
MH
1889 if (remove_empty_directories(git_path("%s", newrefname))) {
1890 error("Directory not empty: %s", newrefname);
c976d415
LH
1891 goto rollback;
1892 }
1893 } else {
dfefa935 1894 error("unable to delete existing %s", newrefname);
c976d415
LH
1895 goto rollback;
1896 }
1897 }
1898
dfefa935
MH
1899 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1900 error("unable to create directory for %s", newrefname);
c976d415
LH
1901 goto rollback;
1902 }
1903
1904 retry:
dfefa935 1905 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1906 if (errno==EISDIR || errno==ENOTDIR) {
1907 /*
1908 * rename(a, b) when b is an existing
1909 * directory ought to result in ISDIR, but
1910 * Solaris 5.8 gives ENOTDIR. Sheesh.
1911 */
dfefa935
MH
1912 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1913 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1914 goto rollback;
1915 }
1916 goto retry;
1917 } else {
765c2258 1918 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1919 newrefname, strerror(errno));
c976d415
LH
1920 goto rollback;
1921 }
1922 }
1923 logmoved = log;
1924
dfefa935 1925 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1926 if (!lock) {
dfefa935 1927 error("unable to lock %s for update", newrefname);
c976d415
LH
1928 goto rollback;
1929 }
c976d415
LH
1930 lock->force_write = 1;
1931 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1932 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1933 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1934 goto rollback;
1935 }
1936
1937 return 0;
1938
1939 rollback:
dfefa935 1940 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1941 if (!lock) {
dfefa935 1942 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1943 goto rollbacklog;
1944 }
1945
1946 lock->force_write = 1;
1947 flag = log_all_ref_updates;
1948 log_all_ref_updates = 0;
1949 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1950 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1951 log_all_ref_updates = flag;
1952
1953 rollbacklog:
dfefa935 1954 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1955 error("unable to restore logfile %s from %s: %s",
dfefa935 1956 oldrefname, newrefname, strerror(errno));
c976d415 1957 if (!logmoved && log &&
dfefa935 1958 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1959 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1960 oldrefname, strerror(errno));
c976d415
LH
1961
1962 return 1;
1963}
1964
435fc852 1965int close_ref(struct ref_lock *lock)
b531394d
BC
1966{
1967 if (close_lock_file(lock->lk))
1968 return -1;
1969 lock->lock_fd = -1;
1970 return 0;
1971}
1972
435fc852 1973int commit_ref(struct ref_lock *lock)
b531394d
BC
1974{
1975 if (commit_lock_file(lock->lk))
1976 return -1;
1977 lock->lock_fd = -1;
1978 return 0;
1979}
1980
e5f38ec3 1981void unlock_ref(struct ref_lock *lock)
4bd18c43 1982{
4ed7cd3a
BC
1983 /* Do not free lock->lk -- atexit() still looks at them */
1984 if (lock->lk)
1985 rollback_lock_file(lock->lk);
434cd0cd 1986 free(lock->ref_name);
1655707c 1987 free(lock->orig_ref_name);
4bd18c43
SP
1988 free(lock);
1989}
1990
0ec29a47
JH
1991/*
1992 * copy the reflog message msg to buf, which has been allocated sufficiently
1993 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1994 * because reflog file is one line per entry.
1995 */
1996static int copy_msg(char *buf, const char *msg)
1997{
1998 char *cp = buf;
1999 char c;
2000 int wasspace = 1;
2001
2002 *cp++ = '\t';
2003 while ((c = *msg++)) {
2004 if (wasspace && isspace(c))
2005 continue;
2006 wasspace = isspace(c);
2007 if (wasspace)
2008 c = ' ';
2009 *cp++ = c;
2010 }
2011 while (buf < cp && isspace(cp[-1]))
2012 cp--;
2013 *cp++ = '\n';
2014 return cp - buf;
2015}
2016
dfefa935 2017int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 2018{
859c3017 2019 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 2020
dfefa935 2021 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 2022 if (log_all_ref_updates &&
dfefa935
MH
2023 (!prefixcmp(refname, "refs/heads/") ||
2024 !prefixcmp(refname, "refs/remotes/") ||
2025 !prefixcmp(refname, "refs/notes/") ||
2026 !strcmp(refname, "HEAD"))) {
157aaea5 2027 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 2028 return error("unable to create directory for %s",
157aaea5 2029 logfile);
6de08ae6
SP
2030 oflags |= O_CREAT;
2031 }
2032
157aaea5 2033 logfd = open(logfile, oflags, 0666);
6de08ae6 2034 if (logfd < 0) {
1974bf62 2035 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 2036 return 0;
3b463c3f
JH
2037
2038 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 2039 if (remove_empty_directories(logfile)) {
3b463c3f 2040 return error("There are still logs under '%s'",
157aaea5 2041 logfile);
3b463c3f 2042 }
157aaea5 2043 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
2044 }
2045
2046 if (logfd < 0)
2047 return error("Unable to append to %s: %s",
157aaea5 2048 logfile, strerror(errno));
6de08ae6
SP
2049 }
2050
157aaea5 2051 adjust_shared_perm(logfile);
859c3017
EM
2052 close(logfd);
2053 return 0;
2054}
443b92b6 2055
dfefa935 2056static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
2057 const unsigned char *new_sha1, const char *msg)
2058{
2059 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2060 unsigned maxlen, len;
2061 int msglen;
157aaea5 2062 char log_file[PATH_MAX];
859c3017
EM
2063 char *logrec;
2064 const char *committer;
2065
2066 if (log_all_ref_updates < 0)
2067 log_all_ref_updates = !is_bare_repository();
2068
dfefa935 2069 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
2070 if (result)
2071 return result;
2072
2073 logfd = open(log_file, oflags);
2074 if (logfd < 0)
2075 return 0;
0ec29a47 2076 msglen = msg ? strlen(msg) : 0;
774751a8 2077 committer = git_committer_info(0);
8ac65937
JH
2078 maxlen = strlen(committer) + msglen + 100;
2079 logrec = xmalloc(maxlen);
2080 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
2081 sha1_to_hex(old_sha1),
2082 sha1_to_hex(new_sha1),
8ac65937
JH
2083 committer);
2084 if (msglen)
0ec29a47 2085 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 2086 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 2087 free(logrec);
91c8d590 2088 if (close(logfd) != 0 || written != len)
9a13f0b7 2089 return error("Unable to append to %s", log_file);
6de08ae6
SP
2090 return 0;
2091}
2092
c3b0dec5
LT
2093static int is_branch(const char *refname)
2094{
2095 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2096}
2097
4bd18c43
SP
2098int write_ref_sha1(struct ref_lock *lock,
2099 const unsigned char *sha1, const char *logmsg)
2100{
2101 static char term = '\n';
c3b0dec5 2102 struct object *o;
4bd18c43
SP
2103
2104 if (!lock)
95fc7512 2105 return -1;
a89fccd2 2106 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
2107 unlock_ref(lock);
2108 return 0;
95fc7512 2109 }
c3b0dec5
LT
2110 o = parse_object(sha1);
2111 if (!o) {
7be8b3ba 2112 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
2113 lock->ref_name, sha1_to_hex(sha1));
2114 unlock_ref(lock);
2115 return -1;
2116 }
2117 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2118 error("Trying to write non-commit object %s to branch %s",
2119 sha1_to_hex(sha1), lock->ref_name);
2120 unlock_ref(lock);
2121 return -1;
2122 }
93822c22
AW
2123 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2124 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 2125 || close_ref(lock) < 0) {
c33d5174 2126 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
2127 unlock_ref(lock);
2128 return -1;
2129 }
8bf90dc9 2130 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
2131 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2132 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2133 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
2134 unlock_ref(lock);
2135 return -1;
2136 }
605fac8b
NP
2137 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2138 /*
2139 * Special hack: If a branch is updated directly and HEAD
2140 * points to it (may happen on the remote side of a push
2141 * for example) then logically the HEAD reflog should be
2142 * updated too.
2143 * A generic solution implies reverse symref information,
2144 * but finding all symrefs pointing to the given branch
2145 * would be rather costly for this rare event (the direct
2146 * update of a branch) to be worth it. So let's cheat and
2147 * check with HEAD only which should cover 99% of all usage
2148 * scenarios (even 100% of the default ones).
2149 */
2150 unsigned char head_sha1[20];
2151 int head_flag;
2152 const char *head_ref;
8cad4744 2153 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2154 if (head_ref && (head_flag & REF_ISSYMREF) &&
2155 !strcmp(head_ref, lock->ref_name))
2156 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2157 }
b531394d 2158 if (commit_ref(lock)) {
434cd0cd 2159 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2160 unlock_ref(lock);
2161 return -1;
2162 }
4bd18c43
SP
2163 unlock_ref(lock);
2164 return 0;
95fc7512 2165}
d556fae2 2166
8b5157e4
NP
2167int create_symref(const char *ref_target, const char *refs_heads_master,
2168 const char *logmsg)
41b625b0
NP
2169{
2170 const char *lockpath;
2171 char ref[1000];
2172 int fd, len, written;
a4f34cbb 2173 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2174 unsigned char old_sha1[20], new_sha1[20];
2175
2176 if (logmsg && read_ref(ref_target, old_sha1))
2177 hashclr(old_sha1);
41b625b0 2178
d48744d1
JH
2179 if (safe_create_leading_directories(git_HEAD) < 0)
2180 return error("unable to create directory for %s", git_HEAD);
2181
41b625b0
NP
2182#ifndef NO_SYMLINK_HEAD
2183 if (prefer_symlink_refs) {
2184 unlink(git_HEAD);
2185 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2186 goto done;
41b625b0
NP
2187 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2188 }
2189#endif
2190
2191 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2192 if (sizeof(ref) <= len) {
2193 error("refname too long: %s", refs_heads_master);
47fc52e2 2194 goto error_free_return;
41b625b0
NP
2195 }
2196 lockpath = mkpath("%s.lock", git_HEAD);
2197 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2198 if (fd < 0) {
2199 error("Unable to open %s for writing", lockpath);
47fc52e2 2200 goto error_free_return;
41b625b0
NP
2201 }
2202 written = write_in_full(fd, ref, len);
91c8d590 2203 if (close(fd) != 0 || written != len) {
41b625b0 2204 error("Unable to write to %s", lockpath);
47fc52e2 2205 goto error_unlink_return;
41b625b0
NP
2206 }
2207 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2208 error("Unable to create %s", git_HEAD);
47fc52e2 2209 goto error_unlink_return;
41b625b0
NP
2210 }
2211 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2212 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2213 error_unlink_return:
691f1a28 2214 unlink_or_warn(lockpath);
47fc52e2
JH
2215 error_free_return:
2216 free(git_HEAD);
2217 return -1;
41b625b0 2218 }
8b5157e4 2219
ee96d11b 2220#ifndef NO_SYMLINK_HEAD
8b5157e4 2221 done:
ee96d11b 2222#endif
8b5157e4
NP
2223 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2224 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2225
47fc52e2 2226 free(git_HEAD);
41b625b0
NP
2227 return 0;
2228}
2229
16d7cc90
JH
2230static char *ref_msg(const char *line, const char *endp)
2231{
2232 const char *ep;
16d7cc90 2233 line += 82;
182af834
PH
2234 ep = memchr(line, '\n', endp - line);
2235 if (!ep)
2236 ep = endp;
2237 return xmemdupz(line, ep - line);
16d7cc90
JH
2238}
2239
dfefa935
MH
2240int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2241 unsigned char *sha1, char **msg,
2242 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2243{
e5229042 2244 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2245 char *tz_c;
e29cb53a 2246 int logfd, tz, reccnt = 0;
d556fae2
SP
2247 struct stat st;
2248 unsigned long date;
e5229042 2249 unsigned char logged_sha1[20];
cb48cb58 2250 void *log_mapped;
dc49cd76 2251 size_t mapsz;
d556fae2 2252
dfefa935 2253 logfile = git_path("logs/%s", refname);
d556fae2
SP
2254 logfd = open(logfile, O_RDONLY, 0);
2255 if (logfd < 0)
d824cbba 2256 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2257 fstat(logfd, &st);
2258 if (!st.st_size)
2259 die("Log %s is empty.", logfile);
dc49cd76
SP
2260 mapsz = xsize_t(st.st_size);
2261 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2262 logdata = log_mapped;
d556fae2
SP
2263 close(logfd);
2264
e5229042 2265 lastrec = NULL;
d556fae2
SP
2266 rec = logend = logdata + st.st_size;
2267 while (logdata < rec) {
e29cb53a 2268 reccnt++;
d556fae2
SP
2269 if (logdata < rec && *(rec-1) == '\n')
2270 rec--;
e5229042
SP
2271 lastgt = NULL;
2272 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2273 rec--;
e5229042
SP
2274 if (*rec == '>')
2275 lastgt = rec;
2276 }
2277 if (!lastgt)
d556fae2 2278 die("Log %s is corrupt.", logfile);
e5229042 2279 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2280 if (date <= at_time || cnt == 0) {
76a44c5c 2281 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2282 if (msg)
2283 *msg = ref_msg(rec, logend);
2284 if (cutoff_time)
2285 *cutoff_time = date;
2286 if (cutoff_tz)
2287 *cutoff_tz = tz;
2288 if (cutoff_cnt)
76a44c5c 2289 *cutoff_cnt = reccnt - 1;
e5229042
SP
2290 if (lastrec) {
2291 if (get_sha1_hex(lastrec, logged_sha1))
2292 die("Log %s is corrupt.", logfile);
2293 if (get_sha1_hex(rec + 41, sha1))
2294 die("Log %s is corrupt.", logfile);
a89fccd2 2295 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2296 warning("Log %s has gap after %s.",
73013afd 2297 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2298 }
e5f38ec3
JH
2299 }
2300 else if (date == at_time) {
e5229042
SP
2301 if (get_sha1_hex(rec + 41, sha1))
2302 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2303 }
2304 else {
e5229042
SP
2305 if (get_sha1_hex(rec + 41, logged_sha1))
2306 die("Log %s is corrupt.", logfile);
a89fccd2 2307 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2308 warning("Log %s unexpectedly ended on %s.",
73013afd 2309 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2310 }
2311 }
dc49cd76 2312 munmap(log_mapped, mapsz);
d556fae2
SP
2313 return 0;
2314 }
e5229042 2315 lastrec = rec;
ab2a1a32
JH
2316 if (cnt > 0)
2317 cnt--;
d556fae2
SP
2318 }
2319
e5229042
SP
2320 rec = logdata;
2321 while (rec < logend && *rec != '>' && *rec != '\n')
2322 rec++;
2323 if (rec == logend || *rec == '\n')
d556fae2 2324 die("Log %s is corrupt.", logfile);
e5229042 2325 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2326 tz = strtoul(tz_c, NULL, 10);
2327 if (get_sha1_hex(logdata, sha1))
2328 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2329 if (is_null_sha1(sha1)) {
2330 if (get_sha1_hex(logdata + 41, sha1))
2331 die("Log %s is corrupt.", logfile);
2332 }
16d7cc90
JH
2333 if (msg)
2334 *msg = ref_msg(logdata, logend);
dc49cd76 2335 munmap(log_mapped, mapsz);
16d7cc90
JH
2336
2337 if (cutoff_time)
2338 *cutoff_time = date;
2339 if (cutoff_tz)
2340 *cutoff_tz = tz;
2341 if (cutoff_cnt)
2342 *cutoff_cnt = reccnt;
2343 return 1;
d556fae2 2344}
2ff81662 2345
dfefa935 2346int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
2347{
2348 const char *logfile;
2349 FILE *logfp;
8ca78803 2350 struct strbuf sb = STRBUF_INIT;
2266bf27 2351 int ret = 0;
2ff81662 2352
dfefa935 2353 logfile = git_path("logs/%s", refname);
2ff81662
JH
2354 logfp = fopen(logfile, "r");
2355 if (!logfp)
883d60fa 2356 return -1;
101d15e0
JH
2357
2358 if (ofs) {
2359 struct stat statbuf;
2360 if (fstat(fileno(logfp), &statbuf) ||
2361 statbuf.st_size < ofs ||
2362 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 2363 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 2364 fclose(logfp);
8ca78803 2365 strbuf_release(&sb);
101d15e0 2366 return -1;
9d33f7c2 2367 }
101d15e0
JH
2368 }
2369
8ca78803 2370 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 2371 unsigned char osha1[20], nsha1[20];
883d60fa
JS
2372 char *email_end, *message;
2373 unsigned long timestamp;
8ca78803 2374 int tz;
2ff81662
JH
2375
2376 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
2377 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2378 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2379 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2380 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
2381 email_end[1] != ' ' ||
2382 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2383 !message || message[0] != ' ' ||
2384 (message[1] != '+' && message[1] != '-') ||
2385 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2386 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2387 continue; /* corrupt? */
883d60fa
JS
2388 email_end[1] = '\0';
2389 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2390 if (message[6] != '\t')
2391 message += 6;
2392 else
2393 message += 7;
8ca78803
RS
2394 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2395 cb_data);
883d60fa 2396 if (ret)
2266bf27 2397 break;
2ff81662
JH
2398 }
2399 fclose(logfp);
8ca78803 2400 strbuf_release(&sb);
2266bf27 2401 return ret;
2ff81662 2402}
e29cb53a 2403
dfefa935 2404int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2405{
dfefa935 2406 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2407}
2408
989c0e5d
MH
2409/*
2410 * Call fn for each reflog in the namespace indicated by name. name
2411 * must be empty or end with '/'. Name will be used as a scratch
2412 * space, but its contents will be restored before return.
2413 */
2414static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 2415{
989c0e5d 2416 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 2417 int retval = 0;
93c603fc 2418 struct dirent *de;
989c0e5d 2419 int oldlen = name->len;
eb8381c8 2420
93c603fc 2421 if (!d)
989c0e5d 2422 return name->len ? errno : 0;
eb8381c8 2423
93c603fc
MH
2424 while ((de = readdir(d)) != NULL) {
2425 struct stat st;
eb8381c8 2426
93c603fc
MH
2427 if (de->d_name[0] == '.')
2428 continue;
93c603fc
MH
2429 if (has_extension(de->d_name, ".lock"))
2430 continue;
989c0e5d
MH
2431 strbuf_addstr(name, de->d_name);
2432 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2433 ; /* silently ignore */
93c603fc 2434 } else {
eb8381c8 2435 if (S_ISDIR(st.st_mode)) {
989c0e5d
MH
2436 strbuf_addch(name, '/');
2437 retval = do_for_each_reflog(name, fn, cb_data);
eb8381c8
NP
2438 } else {
2439 unsigned char sha1[20];
989c0e5d
MH
2440 if (read_ref_full(name->buf, sha1, 0, NULL))
2441 retval = error("bad ref for %s", name->buf);
eb8381c8 2442 else
989c0e5d 2443 retval = fn(name->buf, sha1, 0, cb_data);
eb8381c8
NP
2444 }
2445 if (retval)
2446 break;
2447 }
989c0e5d 2448 strbuf_setlen(name, oldlen);
eb8381c8 2449 }
93c603fc 2450 closedir(d);
eb8381c8
NP
2451 return retval;
2452}
2453
2454int for_each_reflog(each_ref_fn fn, void *cb_data)
2455{
989c0e5d
MH
2456 int retval;
2457 struct strbuf name;
2458 strbuf_init(&name, PATH_MAX);
2459 retval = do_for_each_reflog(&name, fn, cb_data);
2460 strbuf_release(&name);
2461 return retval;
eb8381c8 2462}
3d9f037c
CR
2463
2464int update_ref(const char *action, const char *refname,
2465 const unsigned char *sha1, const unsigned char *oldval,
2466 int flags, enum action_on_err onerr)
2467{
2468 static struct ref_lock *lock;
2469 lock = lock_any_ref_for_update(refname, oldval, flags);
2470 if (!lock) {
2471 const char *str = "Cannot lock the ref '%s'.";
2472 switch (onerr) {
2473 case MSG_ON_ERR: error(str, refname); break;
2474 case DIE_ON_ERR: die(str, refname); break;
2475 case QUIET_ON_ERR: break;
2476 }
2477 return 1;
2478 }
2479 if (write_ref_sha1(lock, sha1, action) < 0) {
2480 const char *str = "Cannot update the ref '%s'.";
2481 switch (onerr) {
2482 case MSG_ON_ERR: error(str, refname); break;
2483 case DIE_ON_ERR: die(str, refname); break;
2484 case QUIET_ON_ERR: break;
2485 }
2486 return 1;
2487 }
2488 return 0;
2489}
cda69f48 2490
5483f799 2491struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2492{
2493 for ( ; list; list = list->next)
2494 if (!strcmp(list->name, name))
5483f799 2495 return (struct ref *)list;
cda69f48
JK
2496 return NULL;
2497}
7c2b3029
JK
2498
2499/*
2500 * generate a format suitable for scanf from a ref_rev_parse_rules
2501 * rule, that is replace the "%.*s" spec with a "%s" spec
2502 */
2503static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2504{
2505 char *spec;
2506
2507 spec = strstr(rule, "%.*s");
2508 if (!spec || strstr(spec + 4, "%.*s"))
2509 die("invalid rule in ref_rev_parse_rules: %s", rule);
2510
2511 /* copy all until spec */
2512 strncpy(scanf_fmt, rule, spec - rule);
2513 scanf_fmt[spec - rule] = '\0';
2514 /* copy new spec */
2515 strcat(scanf_fmt, "%s");
2516 /* copy remaining rule */
2517 strcat(scanf_fmt, spec + 4);
2518
2519 return;
2520}
2521
dfefa935 2522char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2523{
2524 int i;
2525 static char **scanf_fmts;
2526 static int nr_rules;
2527 char *short_name;
2528
2529 /* pre generate scanf formats from ref_rev_parse_rules[] */
2530 if (!nr_rules) {
2531 size_t total_len = 0;
2532
2533 /* the rule list is NULL terminated, count them first */
2534 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2535 /* no +1 because strlen("%s") < strlen("%.*s") */
2536 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2537
2538 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2539
2540 total_len = 0;
2541 for (i = 0; i < nr_rules; i++) {
2542 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2543 + total_len;
2544 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2545 total_len += strlen(ref_rev_parse_rules[i]);
2546 }
2547 }
2548
2549 /* bail out if there are no rules */
2550 if (!nr_rules)
dfefa935 2551 return xstrdup(refname);
7c2b3029 2552
dfefa935
MH
2553 /* buffer for scanf result, at most refname must fit */
2554 short_name = xstrdup(refname);
7c2b3029
JK
2555
2556 /* skip first rule, it will always match */
2557 for (i = nr_rules - 1; i > 0 ; --i) {
2558 int j;
6e7b3309 2559 int rules_to_fail = i;
7c2b3029
JK
2560 int short_name_len;
2561
dfefa935 2562 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2563 continue;
2564
2565 short_name_len = strlen(short_name);
2566
6e7b3309
BW
2567 /*
2568 * in strict mode, all (except the matched one) rules
2569 * must fail to resolve to a valid non-ambiguous ref
2570 */
2571 if (strict)
2572 rules_to_fail = nr_rules;
2573
7c2b3029
JK
2574 /*
2575 * check if the short name resolves to a valid ref,
2576 * but use only rules prior to the matched one
2577 */
6e7b3309 2578 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2579 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2580 char refname[PATH_MAX];
2581
6e7b3309
BW
2582 /* skip matched rule */
2583 if (i == j)
2584 continue;
2585
7c2b3029
JK
2586 /*
2587 * the short name is ambiguous, if it resolves
2588 * (with this previous rule) to a valid ref
2589 * read_ref() returns 0 on success
2590 */
2591 mksnpath(refname, sizeof(refname),
2592 rule, short_name_len, short_name);
c6893323 2593 if (ref_exists(refname))
7c2b3029
JK
2594 break;
2595 }
2596
2597 /*
2598 * short name is non-ambiguous if all previous rules
2599 * haven't resolved to a valid ref
2600 */
6e7b3309 2601 if (j == rules_to_fail)
7c2b3029
JK
2602 return short_name;
2603 }
2604
2605 free(short_name);
dfefa935 2606 return xstrdup(refname);
7c2b3029 2607}