repack_without_ref(): use function get_packed_ref()
[git/git.git] / refs.c
CommitLineData
95fc7512 1#include "cache.h"
85023577 2#include "refs.h"
cf0adba7
JH
3#include "object.h"
4#include "tag.h"
7155b727 5#include "dir.h"
95fc7512 6
bc5fd6d3
MH
7/*
8 * Make sure "ref" is something reasonable to have under ".git/refs/";
9 * We do not like it if:
10 *
11 * - any path component of it begins with ".", or
12 * - it has double dots "..", or
13 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
14 * - it ends with a "/".
15 * - it ends with ".lock"
16 * - it contains a "\" (backslash)
17 */
f4204ab9 18
bc5fd6d3
MH
19/* Return true iff ch is not allowed in reference names. */
20static inline int bad_ref_char(int ch)
21{
22 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
23 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
24 return 1;
25 /* 2.13 Pattern Matching Notation */
26 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
27 return 1;
28 return 0;
29}
30
31/*
32 * Try to read one refname component from the front of refname. Return
33 * the length of the component found, or -1 if the component is not
34 * legal.
35 */
36static int check_refname_component(const char *refname, int flags)
37{
38 const char *cp;
39 char last = '\0';
40
41 for (cp = refname; ; cp++) {
42 char ch = *cp;
43 if (ch == '\0' || ch == '/')
44 break;
45 if (bad_ref_char(ch))
46 return -1; /* Illegal character in refname. */
47 if (last == '.' && ch == '.')
48 return -1; /* Refname contains "..". */
49 if (last == '@' && ch == '{')
50 return -1; /* Refname contains "@{". */
51 last = ch;
52 }
53 if (cp == refname)
dac529e4 54 return 0; /* Component has zero length. */
bc5fd6d3
MH
55 if (refname[0] == '.') {
56 if (!(flags & REFNAME_DOT_COMPONENT))
57 return -1; /* Component starts with '.'. */
58 /*
59 * Even if leading dots are allowed, don't allow "."
60 * as a component (".." is prevented by a rule above).
61 */
62 if (refname[1] == '\0')
63 return -1; /* Component equals ".". */
64 }
65 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
66 return -1; /* Refname ends with ".lock". */
67 return cp - refname;
68}
69
70int check_refname_format(const char *refname, int flags)
71{
72 int component_len, component_count = 0;
73
74 while (1) {
75 /* We are at the start of a path component. */
76 component_len = check_refname_component(refname, flags);
dac529e4 77 if (component_len <= 0) {
bc5fd6d3
MH
78 if ((flags & REFNAME_REFSPEC_PATTERN) &&
79 refname[0] == '*' &&
80 (refname[1] == '\0' || refname[1] == '/')) {
81 /* Accept one wildcard as a full refname component. */
82 flags &= ~REFNAME_REFSPEC_PATTERN;
83 component_len = 1;
84 } else {
85 return -1;
86 }
87 }
88 component_count++;
89 if (refname[component_len] == '\0')
90 break;
91 /* Skip to next component. */
92 refname += component_len + 1;
93 }
94
95 if (refname[component_len - 1] == '.')
96 return -1; /* Refname ends with '.'. */
97 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
98 return -1; /* Refname has only one component. */
99 return 0;
100}
101
102struct ref_entry;
e1e22e37 103
28e6a34e
MH
104/*
105 * Information used (along with the information in ref_entry) to
106 * describe a single cached reference. This data structure only
107 * occurs embedded in a union in struct ref_entry, and only when
108 * (ref_entry->flag & REF_DIR) is zero.
109 */
593f1bb8 110struct ref_value {
6c6f58df
MH
111 /*
112 * The name of the object to which this reference resolves
113 * (which may be a tag object). If REF_ISBROKEN, this is
114 * null. If REF_ISSYMREF, then this is the name of the object
115 * referred to by the last reference in the symlink chain.
116 */
593f1bb8 117 unsigned char sha1[20];
6c6f58df
MH
118
119 /*
120 * If REF_KNOWS_PEELED, then this field holds the peeled value
121 * of this reference, or null if the reference is known not to
122 * be peelable.
123 */
593f1bb8
MH
124 unsigned char peeled[20];
125};
126
f006c42a
MH
127struct ref_cache;
128
28e6a34e
MH
129/*
130 * Information used (along with the information in ref_entry) to
131 * describe a level in the hierarchy of references. This data
132 * structure only occurs embedded in a union in struct ref_entry, and
133 * only when (ref_entry.flag & REF_DIR) is set. In that case,
134 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
135 * in the directory have already been read:
136 *
137 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
138 * or packed references, already read.
139 *
140 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
141 * references that hasn't been read yet (nor has any of its
142 * subdirectories).
143 *
144 * Entries within a directory are stored within a growable array of
145 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
146 * sorted are sorted by their component name in strcmp() order and the
147 * remaining entries are unsorted.
148 *
149 * Loose references are read lazily, one directory at a time. When a
150 * directory of loose references is read, then all of the references
151 * in that directory are stored, and REF_INCOMPLETE stubs are created
152 * for any subdirectories, but the subdirectories themselves are not
153 * read. The reading is triggered by get_ref_dir().
154 */
d3177275 155struct ref_dir {
e9c4c111 156 int nr, alloc;
e6ed3ca6
MH
157
158 /*
159 * Entries with index 0 <= i < sorted are sorted by name. New
160 * entries are appended to the list unsorted, and are sorted
161 * only when required; thus we avoid the need to sort the list
162 * after the addition of every reference.
163 */
164 int sorted;
165
f006c42a
MH
166 /* A pointer to the ref_cache that contains this ref_dir. */
167 struct ref_cache *ref_cache;
168
d3177275 169 struct ref_entry **entries;
e9c4c111
JP
170};
171
89df9c84
MH
172/*
173 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01,
174 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see
175 * refs.h.
176 */
177
178/*
179 * The field ref_entry->u.value.peeled of this value entry contains
180 * the correct peeled value for the reference, which might be
181 * null_sha1 if the reference is not a tag or if it is broken.
182 */
432ad41e 183#define REF_KNOWS_PEELED 0x08
28e6a34e
MH
184
185/* ref_entry represents a directory of references */
432ad41e 186#define REF_DIR 0x10
cf0adba7 187
28e6a34e
MH
188/*
189 * Entry has not yet been read from disk (used only for REF_DIR
190 * entries representing loose references)
191 */
192#define REF_INCOMPLETE 0x20
193
432ad41e
MH
194/*
195 * A ref_entry represents either a reference or a "subdirectory" of
28e6a34e
MH
196 * references.
197 *
198 * Each directory in the reference namespace is represented by a
199 * ref_entry with (flags & REF_DIR) set and containing a subdir member
200 * that holds the entries in that directory that have been read so
201 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
202 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
203 * used for loose reference directories.
204 *
205 * References are represented by a ref_entry with (flags & REF_DIR)
206 * unset and a value member that describes the reference's value. The
207 * flag member is at the ref_entry level, but it is also needed to
208 * interpret the contents of the value field (in other words, a
209 * ref_value object is not very much use without the enclosing
210 * ref_entry).
432ad41e
MH
211 *
212 * Reference names cannot end with slash and directories' names are
213 * always stored with a trailing slash (except for the top-level
214 * directory, which is always denoted by ""). This has two nice
215 * consequences: (1) when the entries in each subdir are sorted
216 * lexicographically by name (as they usually are), the references in
217 * a whole tree can be generated in lexicographic order by traversing
218 * the tree in left-to-right, depth-first order; (2) the names of
219 * references and subdirectories cannot conflict, and therefore the
220 * presence of an empty subdirectory does not block the creation of a
221 * similarly-named reference. (The fact that reference names with the
222 * same leading components can conflict *with each other* is a
223 * separate issue that is regulated by is_refname_available().)
224 *
225 * Please note that the name field contains the fully-qualified
226 * reference (or subdirectory) name. Space could be saved by only
227 * storing the relative names. But that would require the full names
228 * to be generated on the fly when iterating in do_for_each_ref(), and
229 * would break callback functions, who have always been able to assume
230 * that the name strings that they are passed will not be freed during
231 * the iteration.
232 */
bc5fd6d3
MH
233struct ref_entry {
234 unsigned char flag; /* ISSYMREF? ISPACKED? */
593f1bb8 235 union {
432ad41e
MH
236 struct ref_value value; /* if not (flags&REF_DIR) */
237 struct ref_dir subdir; /* if (flags&REF_DIR) */
593f1bb8 238 } u;
432ad41e
MH
239 /*
240 * The full name of the reference (e.g., "refs/heads/master")
241 * or the full name of the directory with a trailing slash
242 * (e.g., "refs/heads/"):
243 */
bc5fd6d3
MH
244 char name[FLEX_ARRAY];
245};
e1e22e37 246
28e6a34e
MH
247static void read_loose_refs(const char *dirname, struct ref_dir *dir);
248
d7826d54
MH
249static struct ref_dir *get_ref_dir(struct ref_entry *entry)
250{
28e6a34e 251 struct ref_dir *dir;
d7826d54 252 assert(entry->flag & REF_DIR);
28e6a34e
MH
253 dir = &entry->u.subdir;
254 if (entry->flag & REF_INCOMPLETE) {
255 read_loose_refs(entry->name, dir);
256 entry->flag &= ~REF_INCOMPLETE;
257 }
258 return dir;
d7826d54
MH
259}
260
cddc4258
MH
261static struct ref_entry *create_ref_entry(const char *refname,
262 const unsigned char *sha1, int flag,
263 int check_name)
e1e22e37
LT
264{
265 int len;
cddc4258 266 struct ref_entry *ref;
e1e22e37 267
09116a1c 268 if (check_name &&
dfefa935
MH
269 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
270 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
271 len = strlen(refname) + 1;
272 ref = xmalloc(sizeof(struct ref_entry) + len);
593f1bb8
MH
273 hashcpy(ref->u.value.sha1, sha1);
274 hashclr(ref->u.value.peeled);
cddc4258
MH
275 memcpy(ref->name, refname, len);
276 ref->flag = flag;
277 return ref;
278}
279
432ad41e
MH
280static void clear_ref_dir(struct ref_dir *dir);
281
732134ed
MH
282static void free_ref_entry(struct ref_entry *entry)
283{
27b5587c
MH
284 if (entry->flag & REF_DIR) {
285 /*
286 * Do not use get_ref_dir() here, as that might
287 * trigger the reading of loose refs.
288 */
289 clear_ref_dir(&entry->u.subdir);
290 }
732134ed
MH
291 free(entry);
292}
293
432ad41e
MH
294/*
295 * Add a ref_entry to the end of dir (unsorted). Entry is always
296 * stored directly in dir; no recursion into subdirectories is
297 * done.
298 */
299static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
cddc4258 300{
432ad41e
MH
301 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
302 dir->entries[dir->nr++] = entry;
654ad400
MH
303 /* optimize for the case that entries are added in order */
304 if (dir->nr == 1 ||
305 (dir->nr == dir->sorted + 1 &&
306 strcmp(dir->entries[dir->nr - 2]->name,
307 dir->entries[dir->nr - 1]->name) < 0))
308 dir->sorted = dir->nr;
c774aab9
JP
309}
310
432ad41e
MH
311/*
312 * Clear and free all entries in dir, recursively.
313 */
d3177275 314static void clear_ref_dir(struct ref_dir *dir)
bc5fd6d3
MH
315{
316 int i;
d3177275
MH
317 for (i = 0; i < dir->nr; i++)
318 free_ref_entry(dir->entries[i]);
319 free(dir->entries);
320 dir->sorted = dir->nr = dir->alloc = 0;
321 dir->entries = NULL;
bc5fd6d3
MH
322}
323
432ad41e
MH
324/*
325 * Create a struct ref_entry object for the specified dirname.
326 * dirname is the name of the directory with a trailing slash (e.g.,
327 * "refs/heads/") or "" for the top-level directory.
328 */
f006c42a 329static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
b9146f51
RS
330 const char *dirname, size_t len,
331 int incomplete)
432ad41e
MH
332{
333 struct ref_entry *direntry;
432ad41e 334 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
b9146f51
RS
335 memcpy(direntry->name, dirname, len);
336 direntry->name[len] = '\0';
f006c42a 337 direntry->u.subdir.ref_cache = ref_cache;
28e6a34e 338 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
432ad41e
MH
339 return direntry;
340}
341
e9c4c111 342static int ref_entry_cmp(const void *a, const void *b)
c774aab9 343{
e9c4c111
JP
344 struct ref_entry *one = *(struct ref_entry **)a;
345 struct ref_entry *two = *(struct ref_entry **)b;
346 return strcmp(one->name, two->name);
347}
c774aab9 348
d3177275 349static void sort_ref_dir(struct ref_dir *dir);
bc5fd6d3 350
e1980c9d
JH
351struct string_slice {
352 size_t len;
353 const char *str;
354};
355
356static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
357{
358 struct string_slice *key = (struct string_slice *)key_;
359 struct ref_entry *ent = *(struct ref_entry **)ent_;
360 int entlen = strlen(ent->name);
361 int cmplen = key->len < entlen ? key->len : entlen;
362 int cmp = memcmp(key->str, ent->name, cmplen);
363 if (cmp)
364 return cmp;
365 return key->len - entlen;
366}
367
432ad41e
MH
368/*
369 * Return the entry with the given refname from the ref_dir
370 * (non-recursively), sorting dir if necessary. Return NULL if no
28e6a34e 371 * such entry is found. dir must already be complete.
432ad41e 372 */
40ad937d
RS
373static struct ref_entry *search_ref_dir(struct ref_dir *dir,
374 const char *refname, size_t len)
bc5fd6d3 375{
e1980c9d
JH
376 struct ref_entry **r;
377 struct string_slice key;
bc5fd6d3 378
432ad41e 379 if (refname == NULL || !dir->nr)
bc5fd6d3
MH
380 return NULL;
381
d3177275 382 sort_ref_dir(dir);
e1980c9d
JH
383 key.len = len;
384 key.str = refname;
385 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
386 ref_entry_cmp_sslice);
bc5fd6d3
MH
387
388 if (r == NULL)
389 return NULL;
390
391 return *r;
392}
393
f348ac92
MH
394/*
395 * Search for a directory entry directly within dir (without
396 * recursing). Sort dir if necessary. subdirname must be a directory
397 * name (i.e., end in '/'). If mkdir is set, then create the
398 * directory if it is missing; otherwise, return NULL if the desired
28e6a34e 399 * directory cannot be found. dir must already be complete.
f348ac92 400 */
3f3aa1bc 401static struct ref_dir *search_for_subdir(struct ref_dir *dir,
dd02e728
RS
402 const char *subdirname, size_t len,
403 int mkdir)
f348ac92 404{
40ad937d 405 struct ref_entry *entry = search_ref_dir(dir, subdirname, len);
f348ac92
MH
406 if (!entry) {
407 if (!mkdir)
408 return NULL;
28e6a34e
MH
409 /*
410 * Since dir is complete, the absence of a subdir
411 * means that the subdir really doesn't exist;
412 * therefore, create an empty record for it but mark
413 * the record complete.
414 */
b9146f51 415 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
f348ac92
MH
416 add_entry_to_dir(dir, entry);
417 }
3f3aa1bc 418 return get_ref_dir(entry);
f348ac92
MH
419}
420
432ad41e
MH
421/*
422 * If refname is a reference name, find the ref_dir within the dir
423 * tree that should hold refname. If refname is a directory name
424 * (i.e., ends in '/'), then return that ref_dir itself. dir must
28e6a34e
MH
425 * represent the top-level directory and must already be complete.
426 * Sort ref_dirs and recurse into subdirectories as necessary. If
427 * mkdir is set, then create any missing directories; otherwise,
428 * return NULL if the desired directory cannot be found.
432ad41e
MH
429 */
430static struct ref_dir *find_containing_dir(struct ref_dir *dir,
431 const char *refname, int mkdir)
432{
5fa04418 433 const char *slash;
5fa04418 434 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
dd02e728 435 size_t dirnamelen = slash - refname + 1;
3f3aa1bc 436 struct ref_dir *subdir;
dd02e728 437 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
663c1295
JH
438 if (!subdir) {
439 dir = NULL;
f348ac92 440 break;
432ad41e 441 }
3f3aa1bc 442 dir = subdir;
432ad41e
MH
443 }
444
432ad41e
MH
445 return dir;
446}
447
448/*
449 * Find the value entry with the given name in dir, sorting ref_dirs
450 * and recursing into subdirectories as necessary. If the name is not
451 * found or it corresponds to a directory entry, return NULL.
452 */
453static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
454{
455 struct ref_entry *entry;
456 dir = find_containing_dir(dir, refname, 0);
457 if (!dir)
458 return NULL;
40ad937d 459 entry = search_ref_dir(dir, refname, strlen(refname));
432ad41e
MH
460 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
461}
462
463/*
464 * Add a ref_entry to the ref_dir (unsorted), recursing into
465 * subdirectories as necessary. dir must represent the top-level
466 * directory. Return 0 on success.
467 */
468static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
469{
470 dir = find_containing_dir(dir, ref->name, 1);
471 if (!dir)
472 return -1;
473 add_entry_to_dir(dir, ref);
474 return 0;
475}
476
202a56a9
MH
477/*
478 * Emit a warning and return true iff ref1 and ref2 have the same name
479 * and the same sha1. Die if they have the same name but different
480 * sha1s.
481 */
482static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
483{
432ad41e 484 if (strcmp(ref1->name, ref2->name))
202a56a9 485 return 0;
432ad41e
MH
486
487 /* Duplicate name; make sure that they don't conflict: */
488
489 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
490 /* This is impossible by construction */
491 die("Reference directory conflict: %s", ref1->name);
492
493 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
494 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
495
496 warning("Duplicated ref: %s", ref1->name);
497 return 1;
202a56a9
MH
498}
499
e6ed3ca6 500/*
432ad41e
MH
501 * Sort the entries in dir non-recursively (if they are not already
502 * sorted) and remove any duplicate entries.
e6ed3ca6 503 */
d3177275 504static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 505{
202a56a9 506 int i, j;
81a79d8e 507 struct ref_entry *last = NULL;
c774aab9 508
e6ed3ca6
MH
509 /*
510 * This check also prevents passing a zero-length array to qsort(),
511 * which is a problem on some platforms.
512 */
d3177275 513 if (dir->sorted == dir->nr)
e9c4c111 514 return;
c774aab9 515
d3177275 516 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 517
81a79d8e
MH
518 /* Remove any duplicates: */
519 for (i = 0, j = 0; j < dir->nr; j++) {
520 struct ref_entry *entry = dir->entries[j];
521 if (last && is_dup_ref(last, entry))
522 free_ref_entry(entry);
523 else
524 last = dir->entries[i++] = entry;
e9c4c111 525 }
81a79d8e 526 dir->sorted = dir->nr = i;
e9c4c111 527}
c774aab9 528
fcce1703
MH
529/* Include broken references in a do_for_each_ref*() iteration: */
530#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
c774aab9 531
7d76fdc8
MH
532/*
533 * current_ref is a performance hack: when iterating over references
534 * using the for_each_ref*() functions, current_ref is set to the
535 * current reference's entry before calling the callback function. If
536 * the callback function calls peel_ref(), then peel_ref() first
537 * checks whether the reference to be peeled is the current reference
538 * (it usually is) and if so, returns that reference's peeled version
539 * if it is available. This avoids a refname lookup in a common case.
540 */
bc5fd6d3 541static struct ref_entry *current_ref;
c774aab9 542
fcce1703
MH
543/*
544 * Handle one reference in a do_for_each_ref*()-style iteration.
545 */
bc5fd6d3
MH
546static int do_one_ref(const char *base, each_ref_fn fn, int trim,
547 int flags, void *cb_data, struct ref_entry *entry)
548{
429213e4 549 int retval;
bc5fd6d3
MH
550 if (prefixcmp(entry->name, base))
551 return 0;
c774aab9 552
bc5fd6d3
MH
553 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
554 if (entry->flag & REF_ISBROKEN)
555 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 556 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
557 error("%s does not point to a valid object!", entry->name);
558 return 0;
559 }
560 }
561 current_ref = entry;
593f1bb8 562 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
563 current_ref = NULL;
564 return retval;
bc5fd6d3 565}
c774aab9 566
c36b5bc2 567/*
d3177275 568 * Call fn for each reference in dir that has index in the range
432ad41e
MH
569 * offset <= index < dir->nr. Recurse into subdirectories that are in
570 * that index range, sorting them before iterating. This function
571 * does not sort dir itself; it should be sorted beforehand.
c36b5bc2 572 */
d3177275
MH
573static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
574 const char *base,
575 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
576{
577 int i;
d3177275
MH
578 assert(dir->sorted == dir->nr);
579 for (i = offset; i < dir->nr; i++) {
432ad41e
MH
580 struct ref_entry *entry = dir->entries[i];
581 int retval;
582 if (entry->flag & REF_DIR) {
d7826d54
MH
583 struct ref_dir *subdir = get_ref_dir(entry);
584 sort_ref_dir(subdir);
585 retval = do_for_each_ref_in_dir(subdir, 0,
432ad41e
MH
586 base, fn, trim, flags, cb_data);
587 } else {
588 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
589 }
c36b5bc2
MH
590 if (retval)
591 return retval;
592 }
593 return 0;
594}
595
b3fd060f 596/*
d3177275 597 * Call fn for each reference in the union of dir1 and dir2, in order
432ad41e
MH
598 * by refname. Recurse into subdirectories. If a value entry appears
599 * in both dir1 and dir2, then only process the version that is in
600 * dir2. The input dirs must already be sorted, but subdirs will be
601 * sorted as needed.
b3fd060f 602 */
d3177275
MH
603static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
604 struct ref_dir *dir2,
605 const char *base, each_ref_fn fn, int trim,
606 int flags, void *cb_data)
b3fd060f
MH
607{
608 int retval;
609 int i1 = 0, i2 = 0;
610
d3177275
MH
611 assert(dir1->sorted == dir1->nr);
612 assert(dir2->sorted == dir2->nr);
432ad41e
MH
613 while (1) {
614 struct ref_entry *e1, *e2;
615 int cmp;
616 if (i1 == dir1->nr) {
617 return do_for_each_ref_in_dir(dir2, i2,
618 base, fn, trim, flags, cb_data);
619 }
620 if (i2 == dir2->nr) {
621 return do_for_each_ref_in_dir(dir1, i1,
622 base, fn, trim, flags, cb_data);
623 }
624 e1 = dir1->entries[i1];
625 e2 = dir2->entries[i2];
626 cmp = strcmp(e1->name, e2->name);
627 if (cmp == 0) {
628 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
629 /* Both are directories; descend them in parallel. */
d7826d54
MH
630 struct ref_dir *subdir1 = get_ref_dir(e1);
631 struct ref_dir *subdir2 = get_ref_dir(e2);
632 sort_ref_dir(subdir1);
633 sort_ref_dir(subdir2);
432ad41e 634 retval = do_for_each_ref_in_dirs(
d7826d54 635 subdir1, subdir2,
432ad41e
MH
636 base, fn, trim, flags, cb_data);
637 i1++;
638 i2++;
639 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
640 /* Both are references; ignore the one from dir1. */
641 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
642 i1++;
643 i2++;
644 } else {
645 die("conflict between reference and directory: %s",
646 e1->name);
647 }
b3fd060f 648 } else {
432ad41e
MH
649 struct ref_entry *e;
650 if (cmp < 0) {
651 e = e1;
b3fd060f 652 i1++;
432ad41e
MH
653 } else {
654 e = e2;
655 i2++;
656 }
657 if (e->flag & REF_DIR) {
d7826d54
MH
658 struct ref_dir *subdir = get_ref_dir(e);
659 sort_ref_dir(subdir);
432ad41e 660 retval = do_for_each_ref_in_dir(
d7826d54 661 subdir, 0,
432ad41e
MH
662 base, fn, trim, flags, cb_data);
663 } else {
664 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
b3fd060f
MH
665 }
666 }
667 if (retval)
668 return retval;
669 }
b3fd060f
MH
670}
671
d66da478
MH
672/*
673 * Return true iff refname1 and refname2 conflict with each other.
674 * Two reference names conflict if one of them exactly matches the
675 * leading components of the other; e.g., "foo/bar" conflicts with
676 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
677 * "foo/barbados".
678 */
679static int names_conflict(const char *refname1, const char *refname2)
680{
5a4d4947
MH
681 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
682 ;
683 return (*refname1 == '\0' && *refname2 == '/')
684 || (*refname1 == '/' && *refname2 == '\0');
685}
686
687struct name_conflict_cb {
688 const char *refname;
689 const char *oldrefname;
690 const char *conflicting_refname;
691};
692
693static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
694 int flags, void *cb_data)
695{
696 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
697 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
698 return 0;
699 if (names_conflict(data->refname, existingrefname)) {
700 data->conflicting_refname = existingrefname;
701 return 1;
d66da478 702 }
5a4d4947 703 return 0;
d66da478
MH
704}
705
bc5fd6d3
MH
706/*
707 * Return true iff a reference named refname could be created without
5a4d4947
MH
708 * conflicting with the name of an existing reference in array. If
709 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
710 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
711 * operation).
712 */
713static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 714 struct ref_dir *dir)
bc5fd6d3 715{
5a4d4947
MH
716 struct name_conflict_cb data;
717 data.refname = refname;
718 data.oldrefname = oldrefname;
719 data.conflicting_refname = NULL;
720
d3177275
MH
721 sort_ref_dir(dir);
722 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
723 0, DO_FOR_EACH_INCLUDE_BROKEN,
724 &data)) {
5a4d4947
MH
725 error("'%s' exists; cannot create '%s'",
726 data.conflicting_refname, refname);
727 return 0;
bc5fd6d3
MH
728 }
729 return 1;
e1e22e37
LT
730}
731
5e290ff7
JH
732/*
733 * Future: need to be in "struct repository"
734 * when doing a full libification.
735 */
79c7ca54
MH
736static struct ref_cache {
737 struct ref_cache *next;
d12229f5
MH
738 struct ref_entry *loose;
739 struct ref_entry *packed;
ce40979c
MH
740 /* The submodule name, or "" for the main repo. */
741 char name[FLEX_ARRAY];
79c7ca54 742} *ref_cache;
0e88c130 743
760c4512 744static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 745{
d12229f5
MH
746 if (refs->packed) {
747 free_ref_entry(refs->packed);
748 refs->packed = NULL;
749 }
5e290ff7 750}
e1e22e37 751
760c4512
MH
752static void clear_loose_ref_cache(struct ref_cache *refs)
753{
d12229f5
MH
754 if (refs->loose) {
755 free_ref_entry(refs->loose);
756 refs->loose = NULL;
757 }
760c4512
MH
758}
759
79c7ca54 760static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 761{
ce40979c 762 int len;
79c7ca54 763 struct ref_cache *refs;
ce40979c
MH
764 if (!submodule)
765 submodule = "";
766 len = strlen(submodule) + 1;
79c7ca54 767 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 768 memcpy(refs->name, submodule, len);
e5dbf605
MH
769 return refs;
770}
771
4349a668 772/*
79c7ca54 773 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
774 * the main repository, use submodule==NULL. The returned structure
775 * will be allocated and initialized but not necessarily populated; it
776 * should not be freed.
777 */
79c7ca54 778static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 779{
79c7ca54 780 struct ref_cache *refs = ref_cache;
0e88c130
MH
781 if (!submodule)
782 submodule = "";
783 while (refs) {
784 if (!strcmp(submodule, refs->name))
785 return refs;
786 refs = refs->next;
4349a668 787 }
0e88c130 788
79c7ca54
MH
789 refs = create_ref_cache(submodule);
790 refs->next = ref_cache;
791 ref_cache = refs;
0e88c130 792 return refs;
4349a668
MH
793}
794
8be8bde7 795void invalidate_ref_cache(const char *submodule)
f130b116 796{
c5f29abd
MH
797 struct ref_cache *refs = get_ref_cache(submodule);
798 clear_packed_ref_cache(refs);
799 clear_loose_ref_cache(refs);
5e290ff7 800}
e1e22e37 801
3feb4f0c
MH
802/* The length of a peeled reference line in packed-refs, including EOL: */
803#define PEELED_LINE_LENGTH 42
804
bc5fd6d3
MH
805/*
806 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
807 * Return a pointer to the refname within the line (null-terminated),
808 * or NULL if there was a problem.
809 */
810static const char *parse_ref_line(char *line, unsigned char *sha1)
811{
812 /*
813 * 42: the answer to everything.
814 *
815 * In this case, it happens to be the answer to
816 * 40 (length of sha1 hex representation)
817 * +1 (space in between hex and name)
818 * +1 (newline at the end of the line)
819 */
820 int len = strlen(line) - 42;
821
822 if (len <= 0)
823 return NULL;
824 if (get_sha1_hex(line, sha1) < 0)
825 return NULL;
826 if (!isspace(line[40]))
827 return NULL;
828 line += 41;
829 if (isspace(*line))
830 return NULL;
831 if (line[len] != '\n')
832 return NULL;
833 line[len] = 0;
834
835 return line;
836}
837
c29c46fa
MH
838/*
839 * Read f, which is a packed-refs file, into dir.
840 *
841 * A comment line of the form "# pack-refs with: " may contain zero or
842 * more traits. We interpret the traits as follows:
843 *
844 * No traits:
845 *
846 * Probably no references are peeled. But if the file contains a
847 * peeled value for a reference, we will use it.
848 *
849 * peeled:
850 *
851 * References under "refs/tags/", if they *can* be peeled, *are*
852 * peeled in this file. References outside of "refs/tags/" are
853 * probably not peeled even if they could have been, but if we find
854 * a peeled value for such a reference we will use it.
855 *
856 * fully-peeled:
857 *
858 * All references in the file that can be peeled are peeled.
859 * Inversely (and this is more important), any references in the
860 * file for which no peeled value is recorded is not peelable. This
861 * trait should typically be written alongside "peeled" for
862 * compatibility with older clients, but we do not require it
863 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
864 */
d3177275 865static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 866{
e9c4c111 867 struct ref_entry *last = NULL;
f4204ab9 868 char refline[PATH_MAX];
c29c46fa 869 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
f4204ab9
JH
870
871 while (fgets(refline, sizeof(refline), f)) {
872 unsigned char sha1[20];
dfefa935 873 const char *refname;
f4204ab9
JH
874 static const char header[] = "# pack-refs with:";
875
876 if (!strncmp(refline, header, sizeof(header)-1)) {
877 const char *traits = refline + sizeof(header) - 1;
c29c46fa
MH
878 if (strstr(traits, " fully-peeled "))
879 peeled = PEELED_FULLY;
880 else if (strstr(traits, " peeled "))
881 peeled = PEELED_TAGS;
f4204ab9
JH
882 /* perhaps other traits later as well */
883 continue;
884 }
885
dfefa935
MH
886 refname = parse_ref_line(refline, sha1);
887 if (refname) {
c29c46fa
MH
888 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
889 if (peeled == PEELED_FULLY ||
890 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
891 last->flag |= REF_KNOWS_PEELED;
d3177275 892 add_ref(dir, last);
f4204ab9
JH
893 continue;
894 }
895 if (last &&
896 refline[0] == '^' &&
3feb4f0c
MH
897 strlen(refline) == PEELED_LINE_LENGTH &&
898 refline[PEELED_LINE_LENGTH - 1] == '\n' &&
c29c46fa 899 !get_sha1_hex(refline + 1, sha1)) {
593f1bb8 900 hashcpy(last->u.value.peeled, sha1);
c29c46fa
MH
901 /*
902 * Regardless of what the file header said,
903 * we definitely know the value of *this*
904 * reference:
905 */
906 last->flag |= REF_KNOWS_PEELED;
907 }
f4204ab9 908 }
f4204ab9
JH
909}
910
d3177275 911static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 912{
d12229f5 913 if (!refs->packed) {
4349a668
MH
914 const char *packed_refs_file;
915 FILE *f;
0bad611b 916
b9146f51 917 refs->packed = create_dir_entry(refs, "", 0, 0);
316b097a
MH
918 if (*refs->name)
919 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
920 else
921 packed_refs_file = git_path("packed-refs");
922 f = fopen(packed_refs_file, "r");
e1e22e37 923 if (f) {
d7826d54 924 read_packed_refs(f, get_ref_dir(refs->packed));
e1e22e37 925 fclose(f);
e1e22e37 926 }
e1e22e37 927 }
d7826d54 928 return get_ref_dir(refs->packed);
e1e22e37
LT
929}
930
30249ee6
MH
931void add_packed_ref(const char *refname, const unsigned char *sha1)
932{
933 add_ref(get_packed_refs(get_ref_cache(NULL)),
934 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
935}
936
abc39098 937/*
28e6a34e
MH
938 * Read the loose references from the namespace dirname into dir
939 * (without recursing). dirname must end with '/'. dir must be the
940 * directory entry corresponding to dirname.
abc39098 941 */
423a1afc 942static void read_loose_refs(const char *dirname, struct ref_dir *dir)
e1e22e37 943{
423a1afc 944 struct ref_cache *refs = dir->ref_cache;
d3177275 945 DIR *d;
0bad611b 946 const char *path;
d5fdae67 947 struct dirent *de;
abc39098 948 int dirnamelen = strlen(dirname);
72b64b44 949 struct strbuf refname;
0bad611b 950
3b124823 951 if (*refs->name)
66a3d20b 952 path = git_path_submodule(refs->name, "%s", dirname);
0bad611b 953 else
66a3d20b 954 path = git_path("%s", dirname);
0bad611b 955
d3177275 956 d = opendir(path);
d5fdae67
MH
957 if (!d)
958 return;
959
66a3d20b
MH
960 strbuf_init(&refname, dirnamelen + 257);
961 strbuf_add(&refname, dirname, dirnamelen);
d5fdae67
MH
962
963 while ((de = readdir(d)) != NULL) {
964 unsigned char sha1[20];
965 struct stat st;
966 int flag;
d5fdae67
MH
967 const char *refdir;
968
969 if (de->d_name[0] == '.')
970 continue;
d5fdae67
MH
971 if (has_extension(de->d_name, ".lock"))
972 continue;
72b64b44 973 strbuf_addstr(&refname, de->d_name);
d5fdae67 974 refdir = *refs->name
72b64b44
MH
975 ? git_path_submodule(refs->name, "%s", refname.buf)
976 : git_path("%s", refname.buf);
977 if (stat(refdir, &st) < 0) {
978 ; /* silently ignore */
979 } else if (S_ISDIR(st.st_mode)) {
abc39098 980 strbuf_addch(&refname, '/');
28e6a34e 981 add_entry_to_dir(dir,
b9146f51
RS
982 create_dir_entry(refs, refname.buf,
983 refname.len, 1));
72b64b44 984 } else {
3b124823 985 if (*refs->name) {
f8948e2f 986 hashclr(sha1);
0bad611b 987 flag = 0;
72b64b44 988 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
0bad611b 989 hashclr(sha1);
98ac34b2 990 flag |= REF_ISBROKEN;
0bad611b 991 }
72b64b44 992 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
09116a1c
JH
993 hashclr(sha1);
994 flag |= REF_ISBROKEN;
995 }
9f2fb4a3
MH
996 add_entry_to_dir(dir,
997 create_ref_entry(refname.buf, sha1, flag, 1));
e1e22e37 998 }
66a3d20b 999 strbuf_setlen(&refname, dirnamelen);
e1e22e37 1000 }
72b64b44 1001 strbuf_release(&refname);
d5fdae67 1002 closedir(d);
e1e22e37
LT
1003}
1004
d3177275 1005static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 1006{
d12229f5 1007 if (!refs->loose) {
28e6a34e
MH
1008 /*
1009 * Mark the top-level directory complete because we
1010 * are about to read the only subdirectory that can
1011 * hold references:
1012 */
b9146f51 1013 refs->loose = create_dir_entry(refs, "", 0, 0);
28e6a34e
MH
1014 /*
1015 * Create an incomplete entry for "refs/":
1016 */
1017 add_entry_to_dir(get_ref_dir(refs->loose),
b9146f51 1018 create_dir_entry(refs, "refs/", 5, 1));
e1e22e37 1019 }
d7826d54 1020 return get_ref_dir(refs->loose);
e1e22e37
LT
1021}
1022
ca8db142
LT
1023/* We allow "recursive" symbolic refs. Only within reason, though */
1024#define MAXDEPTH 5
0ebde32c
LT
1025#define MAXREFLEN (1024)
1026
e5fa45c1
JH
1027/*
1028 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
1029 * from the loose refs in ref_cache refs. Find <refname> in the
1030 * packed-refs file for the submodule.
e5fa45c1 1031 */
b0626608 1032static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 1033 const char *refname, unsigned char *sha1)
0ebde32c 1034{
2c5c66be 1035 struct ref_entry *ref;
d3177275 1036 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 1037
432ad41e 1038 ref = find_ref(dir, refname);
b0626608
MH
1039 if (ref == NULL)
1040 return -1;
1041
593f1bb8 1042 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 1043 return 0;
0ebde32c
LT
1044}
1045
b0626608 1046static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 1047 const char *refname, unsigned char *sha1,
dfefa935 1048 int recursion)
0ebde32c 1049{
064d51dc 1050 int fd, len;
0ebde32c 1051 char buffer[128], *p;
064d51dc 1052 char *path;
0ebde32c 1053
064d51dc 1054 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 1055 return -1;
064d51dc
MH
1056 path = *refs->name
1057 ? git_path_submodule(refs->name, "%s", refname)
1058 : git_path("%s", refname);
1059 fd = open(path, O_RDONLY);
0ebde32c 1060 if (fd < 0)
b0626608 1061 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
1062
1063 len = read(fd, buffer, sizeof(buffer)-1);
1064 close(fd);
1065 if (len < 0)
1066 return -1;
1067 while (len && isspace(buffer[len-1]))
1068 len--;
1069 buffer[len] = 0;
1070
1071 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 1072 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
1073 return 0;
1074
1075 /* Symref? */
1076 if (strncmp(buffer, "ref:", 4))
1077 return -1;
1078 p = buffer + 4;
1079 while (isspace(*p))
1080 p++;
1081
064d51dc 1082 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
1083}
1084
85be1fe3 1085int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
1086{
1087 int len = strlen(path), retval;
064d51dc 1088 char *submodule;
b0626608 1089 struct ref_cache *refs;
0ebde32c
LT
1090
1091 while (len && path[len-1] == '/')
1092 len--;
1093 if (!len)
1094 return -1;
b0626608
MH
1095 submodule = xstrndup(path, len);
1096 refs = get_ref_cache(submodule);
1097 free(submodule);
1098
064d51dc 1099 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
1100 return retval;
1101}
ca8db142 1102
4886b89f 1103/*
63331581
MH
1104 * Return the ref_entry for the given refname from the packed
1105 * references. If it does not exist, return NULL.
4886b89f 1106 */
63331581 1107static struct ref_entry *get_packed_ref(const char *refname)
c224ca7f 1108{
63331581 1109 return find_ref(get_packed_refs(get_ref_cache(NULL)), refname);
c224ca7f
MH
1110}
1111
8d68493f 1112const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 1113{
0104ca09
HO
1114 int depth = MAXDEPTH;
1115 ssize_t len;
a876ed83 1116 char buffer[256];
dfefa935 1117 static char refname_buffer[256];
ca8db142 1118
8da19775
JH
1119 if (flag)
1120 *flag = 0;
1121
dfefa935 1122 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
1123 return NULL;
1124
a876ed83 1125 for (;;) {
55956350 1126 char path[PATH_MAX];
a876ed83
JH
1127 struct stat st;
1128 char *buf;
1129 int fd;
8a65ff76 1130
a876ed83
JH
1131 if (--depth < 0)
1132 return NULL;
ca8db142 1133
dfefa935 1134 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 1135
a876ed83 1136 if (lstat(path, &st) < 0) {
63331581
MH
1137 struct ref_entry *entry;
1138
c224ca7f
MH
1139 if (errno != ENOENT)
1140 return NULL;
1141 /*
1142 * The loose reference file does not exist;
1143 * check for a packed reference.
1144 */
63331581
MH
1145 entry = get_packed_ref(refname);
1146 if (entry) {
1147 hashcpy(sha1, entry->u.value.sha1);
c224ca7f
MH
1148 if (flag)
1149 *flag |= REF_ISPACKED;
dfefa935 1150 return refname;
434cd0cd 1151 }
c224ca7f
MH
1152 /* The reference is not a packed reference, either. */
1153 if (reading) {
a876ed83 1154 return NULL;
c224ca7f
MH
1155 } else {
1156 hashclr(sha1);
dfefa935 1157 return refname;
c224ca7f 1158 }
a876ed83 1159 }
ca8db142 1160
a876ed83
JH
1161 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1162 if (S_ISLNK(st.st_mode)) {
1163 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
1164 if (len < 0)
1165 return NULL;
b54cb795 1166 buffer[len] = 0;
1f58a038
MH
1167 if (!prefixcmp(buffer, "refs/") &&
1168 !check_refname_format(buffer, 0)) {
dfefa935
MH
1169 strcpy(refname_buffer, buffer);
1170 refname = refname_buffer;
8da19775
JH
1171 if (flag)
1172 *flag |= REF_ISSYMREF;
a876ed83
JH
1173 continue;
1174 }
ca8db142 1175 }
a876ed83 1176
7a21632f
DS
1177 /* Is it a directory? */
1178 if (S_ISDIR(st.st_mode)) {
1179 errno = EISDIR;
1180 return NULL;
1181 }
1182
a876ed83
JH
1183 /*
1184 * Anything else, just open it and try to use it as
1185 * a ref
1186 */
1187 fd = open(path, O_RDONLY);
1188 if (fd < 0)
1189 return NULL;
93d26e4c 1190 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 1191 close(fd);
28775050
MH
1192 if (len < 0)
1193 return NULL;
1194 while (len && isspace(buffer[len-1]))
1195 len--;
1196 buffer[len] = '\0';
a876ed83
JH
1197
1198 /*
1199 * Is it a symbolic ref?
1200 */
28775050 1201 if (prefixcmp(buffer, "ref:"))
a876ed83 1202 break;
55956350
JH
1203 if (flag)
1204 *flag |= REF_ISSYMREF;
a876ed83 1205 buf = buffer + 4;
28775050
MH
1206 while (isspace(*buf))
1207 buf++;
313fb010 1208 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
1209 if (flag)
1210 *flag |= REF_ISBROKEN;
313fb010
MH
1211 return NULL;
1212 }
dfefa935 1213 refname = strcpy(refname_buffer, buf);
8a65ff76 1214 }
f989fea0
MH
1215 /* Please note that FETCH_HEAD has a second line containing other data. */
1216 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
1217 if (flag)
1218 *flag |= REF_ISBROKEN;
a876ed83 1219 return NULL;
629cd3ac 1220 }
dfefa935 1221 return refname;
a876ed83
JH
1222}
1223
96ec7b1e
NTND
1224char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1225{
8cad4744 1226 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
1227 return ret ? xstrdup(ret) : NULL;
1228}
1229
d08bae7e
IL
1230/* The argument to filter_refs */
1231struct ref_filter {
1232 const char *pattern;
1233 each_ref_fn *fn;
1234 void *cb_data;
1235};
1236
dfefa935 1237int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 1238{
8d68493f 1239 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
1240 return 0;
1241 return -1;
8a65ff76
LT
1242}
1243
dfefa935 1244int read_ref(const char *refname, unsigned char *sha1)
c6893323 1245{
dfefa935 1246 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
1247}
1248
bc5fd6d3 1249int ref_exists(const char *refname)
ef06b918 1250{
bc5fd6d3
MH
1251 unsigned char sha1[20];
1252 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
1253}
1254
85be1fe3 1255static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 1256 void *data)
d08bae7e
IL
1257{
1258 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 1259 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 1260 return 0;
85be1fe3 1261 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
1262}
1263
dfefa935 1264int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
1265{
1266 int flag;
1267 unsigned char base[20];
1268 struct object *o;
1269
dfefa935
MH
1270 if (current_ref && (current_ref->name == refname
1271 || !strcmp(current_ref->name, refname))) {
0ae91be0 1272 if (current_ref->flag & REF_KNOWS_PEELED) {
e6dbffa6
JK
1273 if (is_null_sha1(current_ref->u.value.peeled))
1274 return -1;
593f1bb8 1275 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
1276 return 0;
1277 }
593f1bb8 1278 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
1279 goto fallback;
1280 }
1281
dfefa935 1282 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
1283 return -1;
1284
1285 if ((flag & REF_ISPACKED)) {
f361baeb 1286 struct ref_entry *r = get_packed_ref(refname);
cf0adba7 1287
f361baeb 1288 if (r && (r->flag & REF_KNOWS_PEELED)) {
593f1bb8 1289 hashcpy(sha1, r->u.value.peeled);
e9c4c111 1290 return 0;
cf0adba7 1291 }
cf0adba7
JH
1292 }
1293
0ae91be0 1294fallback:
6c4a060d
JK
1295 o = lookup_unknown_object(base);
1296 if (o->type == OBJ_NONE) {
1297 int type = sha1_object_info(base, NULL);
1298 if (type < 0)
1299 return -1;
1300 o->type = type;
1301 }
1302
1303 if (o->type == OBJ_TAG) {
44da6f69 1304 o = deref_tag_noverify(o);
cf0adba7
JH
1305 if (o) {
1306 hashcpy(sha1, o->sha1);
1307 return 0;
1308 }
1309 }
1310 return -1;
1311}
1312
bc5fd6d3
MH
1313struct warn_if_dangling_data {
1314 FILE *fp;
1315 const char *refname;
1316 const char *msg_fmt;
1317};
1318
1319static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1320 int flags, void *cb_data)
1321{
1322 struct warn_if_dangling_data *d = cb_data;
1323 const char *resolves_to;
1324 unsigned char junk[20];
1325
1326 if (!(flags & REF_ISSYMREF))
1327 return 0;
1328
1329 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1330 if (!resolves_to || strcmp(resolves_to, d->refname))
1331 return 0;
1332
1333 fprintf(d->fp, d->msg_fmt, refname);
1be65eda 1334 fputc('\n', d->fp);
bc5fd6d3
MH
1335 return 0;
1336}
1337
1338void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1339{
1340 struct warn_if_dangling_data data;
1341
1342 data.fp = fp;
1343 data.refname = refname;
1344 data.msg_fmt = msg_fmt;
1345 for_each_rawref(warn_if_dangling_symref, &data);
1346}
1347
fcce1703
MH
1348/*
1349 * Call fn for each reference in the specified submodule for which the
1350 * refname begins with base. If trim is non-zero, then trim that many
1351 * characters off the beginning of each refname before passing the
1352 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include
1353 * broken references in the iteration. If fn ever returns a non-zero
1354 * value, stop the iteration and return that value; otherwise, return
1355 * 0.
1356 */
0bad611b
HV
1357static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1358 int trim, int flags, void *cb_data)
8a65ff76 1359{
316b097a 1360 struct ref_cache *refs = get_ref_cache(submodule);
933ac036
MH
1361 struct ref_dir *packed_dir = get_packed_refs(refs);
1362 struct ref_dir *loose_dir = get_loose_refs(refs);
1363 int retval = 0;
1364
1365 if (base && *base) {
1366 packed_dir = find_containing_dir(packed_dir, base, 0);
1367 loose_dir = find_containing_dir(loose_dir, base, 0);
1368 }
1369
1370 if (packed_dir && loose_dir) {
1371 sort_ref_dir(packed_dir);
1372 sort_ref_dir(loose_dir);
1373 retval = do_for_each_ref_in_dirs(
1374 packed_dir, loose_dir,
1375 base, fn, trim, flags, cb_data);
1376 } else if (packed_dir) {
1377 sort_ref_dir(packed_dir);
1378 retval = do_for_each_ref_in_dir(
1379 packed_dir, 0,
1380 base, fn, trim, flags, cb_data);
1381 } else if (loose_dir) {
1382 sort_ref_dir(loose_dir);
1383 retval = do_for_each_ref_in_dir(
1384 loose_dir, 0,
1385 base, fn, trim, flags, cb_data);
1386 }
1387
1388 return retval;
8a65ff76
LT
1389}
1390
0bad611b 1391static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
1392{
1393 unsigned char sha1[20];
8da19775
JH
1394 int flag;
1395
0bad611b
HV
1396 if (submodule) {
1397 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1398 return fn("HEAD", sha1, 0, cb_data);
1399
1400 return 0;
1401 }
1402
c6893323 1403 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 1404 return fn("HEAD", sha1, flag, cb_data);
0bad611b 1405
2f34ba32 1406 return 0;
723c31fe
LT
1407}
1408
0bad611b
HV
1409int head_ref(each_ref_fn fn, void *cb_data)
1410{
1411 return do_head_ref(NULL, fn, cb_data);
1412}
1413
9ef6aeb0
HV
1414int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1415{
1416 return do_head_ref(submodule, fn, cb_data);
1417}
1418
cb5d709f 1419int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1420{
b3cfc406 1421 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1422}
1423
9ef6aeb0
HV
1424int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1425{
b3cfc406 1426 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1427}
1428
2a8177b6
CC
1429int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1430{
0bad611b 1431 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1432}
1433
9ef6aeb0
HV
1434int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1435 each_ref_fn fn, void *cb_data)
1436{
1437 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1438}
1439
cb5d709f 1440int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1441{
2a8177b6 1442 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1443}
1444
9ef6aeb0
HV
1445int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1446{
1447 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1448}
1449
cb5d709f 1450int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1451{
2a8177b6 1452 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1453}
1454
9ef6aeb0
HV
1455int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1456{
1457 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1458}
1459
cb5d709f 1460int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1461{
2a8177b6 1462 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1463}
1464
9ef6aeb0
HV
1465int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1466{
1467 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1468}
1469
29268700
CC
1470int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1471{
0bad611b 1472 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1473}
1474
a1bea2c1
JT
1475int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1476{
1477 struct strbuf buf = STRBUF_INIT;
1478 int ret = 0;
1479 unsigned char sha1[20];
1480 int flag;
1481
1482 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1483 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1484 ret = fn(buf.buf, sha1, flag, cb_data);
1485 strbuf_release(&buf);
1486
1487 return ret;
1488}
1489
1490int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1491{
1492 struct strbuf buf = STRBUF_INIT;
1493 int ret;
1494 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1495 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1496 strbuf_release(&buf);
1497 return ret;
1498}
1499
b09fe971
IL
1500int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1501 const char *prefix, void *cb_data)
d08bae7e
IL
1502{
1503 struct strbuf real_pattern = STRBUF_INIT;
1504 struct ref_filter filter;
d08bae7e
IL
1505 int ret;
1506
b09fe971 1507 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1508 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1509 else if (prefix)
1510 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1511 strbuf_addstr(&real_pattern, pattern);
1512
894a9d33 1513 if (!has_glob_specials(pattern)) {
9517e6b8 1514 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1515 if (real_pattern.buf[real_pattern.len - 1] != '/')
1516 strbuf_addch(&real_pattern, '/');
1517 /* No need to check for '*', there is none. */
1518 strbuf_addch(&real_pattern, '*');
1519 }
1520
1521 filter.pattern = real_pattern.buf;
1522 filter.fn = fn;
1523 filter.cb_data = cb_data;
1524 ret = for_each_ref(filter_refs, &filter);
1525
1526 strbuf_release(&real_pattern);
1527 return ret;
1528}
1529
b09fe971
IL
1530int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1531{
1532 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1533}
1534
f8948e2f
JH
1535int for_each_rawref(each_ref_fn fn, void *cb_data)
1536{
b3cfc406 1537 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1538 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1539}
1540
4577e483 1541const char *prettify_refname(const char *name)
a9c37a72 1542{
a9c37a72
DB
1543 return name + (
1544 !prefixcmp(name, "refs/heads/") ? 11 :
1545 !prefixcmp(name, "refs/tags/") ? 10 :
1546 !prefixcmp(name, "refs/remotes/") ? 13 :
1547 0);
1548}
1549
79803322
SP
1550const char *ref_rev_parse_rules[] = {
1551 "%.*s",
1552 "refs/%.*s",
1553 "refs/tags/%.*s",
1554 "refs/heads/%.*s",
1555 "refs/remotes/%.*s",
1556 "refs/remotes/%.*s/HEAD",
1557 NULL
1558};
1559
1560int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1561{
1562 const char **p;
1563 const int abbrev_name_len = strlen(abbrev_name);
1564
1565 for (p = rules; *p; p++) {
1566 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1567 return 1;
1568 }
1569 }
1570
1571 return 0;
1572}
1573
e5f38ec3 1574static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1575 const unsigned char *old_sha1, int mustexist)
1576{
c6893323 1577 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1578 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1579 unlock_ref(lock);
1580 return NULL;
1581 }
a89fccd2 1582 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1583 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1584 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1585 unlock_ref(lock);
1586 return NULL;
1587 }
1588 return lock;
1589}
1590
7155b727 1591static int remove_empty_directories(const char *file)
bc7127ef
JH
1592{
1593 /* we want to create a file but there is a directory there;
1594 * if that is an empty directory (or a directory that contains
1595 * only empty directories), remove them.
1596 */
7155b727
JS
1597 struct strbuf path;
1598 int result;
bc7127ef 1599
7155b727
JS
1600 strbuf_init(&path, 20);
1601 strbuf_addstr(&path, file);
1602
a0f4afbe 1603 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1604
1605 strbuf_release(&path);
1606
1607 return result;
bc7127ef
JH
1608}
1609
ff74f7f1
JH
1610/*
1611 * *string and *len will only be substituted, and *string returned (for
1612 * later free()ing) if the string passed in is a magic short-hand form
1613 * to name a branch.
1614 */
1615static char *substitute_branch_name(const char **string, int *len)
1616{
1617 struct strbuf buf = STRBUF_INIT;
1618 int ret = interpret_branch_name(*string, &buf);
1619
1620 if (ret == *len) {
1621 size_t size;
1622 *string = strbuf_detach(&buf, &size);
1623 *len = size;
1624 return (char *)*string;
1625 }
1626
1627 return NULL;
1628}
1629
1630int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1631{
1632 char *last_branch = substitute_branch_name(&str, &len);
1633 const char **p, *r;
1634 int refs_found = 0;
1635
1636 *ref = NULL;
1637 for (p = ref_rev_parse_rules; *p; p++) {
1638 char fullref[PATH_MAX];
1639 unsigned char sha1_from_ref[20];
1640 unsigned char *this_result;
1641 int flag;
1642
1643 this_result = refs_found ? sha1_from_ref : sha1;
1644 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1645 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1646 if (r) {
1647 if (!refs_found++)
1648 *ref = xstrdup(r);
1649 if (!warn_ambiguous_refs)
1650 break;
55956350 1651 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1652 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1653 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1654 warning("ignoring broken ref %s.", fullref);
1655 }
ff74f7f1
JH
1656 }
1657 free(last_branch);
1658 return refs_found;
1659}
1660
1661int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1662{
1663 char *last_branch = substitute_branch_name(&str, &len);
1664 const char **p;
1665 int logs_found = 0;
1666
1667 *log = NULL;
1668 for (p = ref_rev_parse_rules; *p; p++) {
1669 struct stat st;
1670 unsigned char hash[20];
1671 char path[PATH_MAX];
1672 const char *ref, *it;
1673
1674 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1675 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1676 if (!ref)
1677 continue;
1678 if (!stat(git_path("logs/%s", path), &st) &&
1679 S_ISREG(st.st_mode))
1680 it = path;
1681 else if (strcmp(ref, path) &&
1682 !stat(git_path("logs/%s", ref), &st) &&
1683 S_ISREG(st.st_mode))
1684 it = ref;
1685 else
1686 continue;
1687 if (!logs_found++) {
1688 *log = xstrdup(it);
1689 hashcpy(sha1, hash);
1690 }
1691 if (!warn_ambiguous_refs)
1692 break;
1693 }
1694 free(last_branch);
1695 return logs_found;
1696}
1697
dfefa935
MH
1698static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1699 const unsigned char *old_sha1,
1700 int flags, int *type_p)
4bd18c43 1701{
434cd0cd 1702 char *ref_file;
dfefa935 1703 const char *orig_refname = refname;
4bd18c43 1704 struct ref_lock *lock;
5cc3cef9 1705 int last_errno = 0;
acd3b9ec 1706 int type, lflags;
4431fcc4 1707 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1708 int missing = 0;
4bd18c43
SP
1709
1710 lock = xcalloc(1, sizeof(struct ref_lock));
1711 lock->lock_fd = -1;
1712
8d68493f 1713 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1714 if (!refname && errno == EISDIR) {
bc7127ef
JH
1715 /* we are trying to lock foo but we used to
1716 * have foo/bar which now does not exist;
1717 * it is normal for the empty directory 'foo'
1718 * to remain.
1719 */
dfefa935 1720 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1721 if (remove_empty_directories(ref_file)) {
1722 last_errno = errno;
dfefa935 1723 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1724 goto error_return;
1725 }
8d68493f 1726 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1727 }
68db31cc
SV
1728 if (type_p)
1729 *type_p = type;
dfefa935 1730 if (!refname) {
5cc3cef9 1731 last_errno = errno;
818f477c 1732 error("unable to resolve reference %s: %s",
dfefa935 1733 orig_refname, strerror(errno));
5cc3cef9 1734 goto error_return;
4bd18c43 1735 }
5bdd8d4a 1736 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1737 /* When the ref did not exist and we are creating it,
1738 * make sure there is no existing ref that is packed
1739 * whose name begins with our refname, nor a ref whose
1740 * name is a proper prefix of our refname.
1741 */
5bdd8d4a 1742 if (missing &&
316b097a 1743 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1744 last_errno = ENOTDIR;
c976d415 1745 goto error_return;
f475e08e 1746 }
22a3844e 1747
c33d5174 1748 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1749
acd3b9ec
JH
1750 lflags = LOCK_DIE_ON_ERROR;
1751 if (flags & REF_NODEREF) {
dfefa935 1752 refname = orig_refname;
acd3b9ec
JH
1753 lflags |= LOCK_NODEREF;
1754 }
dfefa935
MH
1755 lock->ref_name = xstrdup(refname);
1756 lock->orig_ref_name = xstrdup(orig_refname);
1757 ref_file = git_path("%s", refname);
5bdd8d4a 1758 if (missing)
68db31cc
SV
1759 lock->force_write = 1;
1760 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1761 lock->force_write = 1;
4bd18c43 1762
5cc3cef9
JH
1763 if (safe_create_leading_directories(ref_file)) {
1764 last_errno = errno;
1765 error("unable to create directory for %s", ref_file);
1766 goto error_return;
1767 }
4bd18c43 1768
acd3b9ec 1769 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1770 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1771
1772 error_return:
1773 unlock_ref(lock);
1774 errno = last_errno;
1775 return NULL;
4bd18c43
SP
1776}
1777
dfefa935 1778struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1779{
53cce84c 1780 char refpath[PATH_MAX];
dfefa935 1781 if (check_refname_format(refname, 0))
4bd18c43 1782 return NULL;
dfefa935 1783 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1784 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1785}
1786
dfefa935
MH
1787struct ref_lock *lock_any_ref_for_update(const char *refname,
1788 const unsigned char *old_sha1, int flags)
4bd18c43 1789{
dfefa935 1790 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1791 return NULL;
dfefa935 1792 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1793}
1794
d66da478
MH
1795struct repack_without_ref_sb {
1796 const char *refname;
1797 int fd;
1798};
1799
1800static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1801 int flags, void *cb_data)
1802{
1803 struct repack_without_ref_sb *data = cb_data;
1804 char line[PATH_MAX + 100];
1805 int len;
1806
1807 if (!strcmp(data->refname, refname))
1808 return 0;
1809 len = snprintf(line, sizeof(line), "%s %s\n",
1810 sha1_to_hex(sha1), refname);
1811 /* this should not happen but just being defensive */
1812 if (len > sizeof(line))
1813 die("too long a refname '%s'", refname);
1814 write_or_die(data->fd, line, len);
1815 return 0;
1816}
1817
26a063a1
JH
1818static struct lock_file packlock;
1819
c0277d15
JH
1820static int repack_without_ref(const char *refname)
1821{
d66da478 1822 struct repack_without_ref_sb data;
b3f1280e 1823 struct ref_cache *refs = get_ref_cache(NULL);
7618fd80
MH
1824 struct ref_dir *packed;
1825
1826 if (!get_packed_ref(refname))
1827 return 0; /* refname does not exist in packed refs */
1828
d66da478
MH
1829 data.refname = refname;
1830 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1831 if (data.fd < 0) {
1b018fd9 1832 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1833 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1834 }
b3f1280e
JK
1835 clear_packed_ref_cache(refs);
1836 packed = get_packed_refs(refs);
d3177275 1837 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1838 return commit_lock_file(&packlock);
1839}
1840
eca35a25 1841int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1842{
1843 struct ref_lock *lock;
eca35a25 1844 int err, i = 0, ret = 0, flag = 0;
c0277d15 1845
547d058f 1846 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
c0277d15
JH
1847 if (!lock)
1848 return 1;
045a476f 1849 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1850 /* loose */
547d058f
RS
1851 i = strlen(lock->lk->filename) - 5; /* .lock */
1852 lock->lk->filename[i] = 0;
1853 err = unlink_or_warn(lock->lk->filename);
691f1a28 1854 if (err && errno != ENOENT)
c0277d15 1855 ret = 1;
691f1a28 1856
547d058f 1857 lock->lk->filename[i] = '.';
c0277d15
JH
1858 }
1859 /* removing the loose one could have resurrected an earlier
1860 * packed one. Also, if it was not loose we need to repack
1861 * without it.
1862 */
b274a714 1863 ret |= repack_without_ref(lock->ref_name);
c0277d15 1864
691f1a28 1865 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1866 invalidate_ref_cache(NULL);
c0277d15
JH
1867 unlock_ref(lock);
1868 return ret;
4bd18c43
SP
1869}
1870
765c2258
PH
1871/*
1872 * People using contrib's git-new-workdir have .git/logs/refs ->
1873 * /some/other/path/.git/logs/refs, and that may live on another device.
1874 *
1875 * IOW, to avoid cross device rename errors, the temporary renamed log must
1876 * live into logs/refs.
1877 */
1878#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1879
dfefa935 1880int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1881{
c976d415
LH
1882 unsigned char sha1[20], orig_sha1[20];
1883 int flag = 0, logmoved = 0;
1884 struct ref_lock *lock;
c976d415 1885 struct stat loginfo;
dfefa935 1886 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1887 const char *symref = NULL;
316b097a 1888 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1889
450d4c0f 1890 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1891 return error("reflog for %s is a symlink", oldrefname);
c976d415 1892
8d68493f 1893 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1894 if (flag & REF_ISSYMREF)
fa58186c 1895 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1896 oldrefname);
eca35a25 1897 if (!symref)
dfefa935 1898 return error("refname %s not found", oldrefname);
c976d415 1899
316b097a 1900 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1901 return 1;
1902
316b097a 1903 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1904 return 1;
1905
dfefa935 1906 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1907 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1908 oldrefname, strerror(errno));
c976d415 1909
dfefa935
MH
1910 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1911 error("unable to delete old %s", oldrefname);
c976d415
LH
1912 goto rollback;
1913 }
1914
dfefa935
MH
1915 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1916 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1917 if (errno==EISDIR) {
dfefa935
MH
1918 if (remove_empty_directories(git_path("%s", newrefname))) {
1919 error("Directory not empty: %s", newrefname);
c976d415
LH
1920 goto rollback;
1921 }
1922 } else {
dfefa935 1923 error("unable to delete existing %s", newrefname);
c976d415
LH
1924 goto rollback;
1925 }
1926 }
1927
dfefa935
MH
1928 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1929 error("unable to create directory for %s", newrefname);
c976d415
LH
1930 goto rollback;
1931 }
1932
1933 retry:
dfefa935 1934 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1935 if (errno==EISDIR || errno==ENOTDIR) {
1936 /*
1937 * rename(a, b) when b is an existing
1938 * directory ought to result in ISDIR, but
1939 * Solaris 5.8 gives ENOTDIR. Sheesh.
1940 */
dfefa935
MH
1941 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1942 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1943 goto rollback;
1944 }
1945 goto retry;
1946 } else {
765c2258 1947 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1948 newrefname, strerror(errno));
c976d415
LH
1949 goto rollback;
1950 }
1951 }
1952 logmoved = log;
1953
dfefa935 1954 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1955 if (!lock) {
dfefa935 1956 error("unable to lock %s for update", newrefname);
c976d415
LH
1957 goto rollback;
1958 }
c976d415
LH
1959 lock->force_write = 1;
1960 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1961 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1962 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1963 goto rollback;
1964 }
1965
1966 return 0;
1967
1968 rollback:
dfefa935 1969 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1970 if (!lock) {
dfefa935 1971 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1972 goto rollbacklog;
1973 }
1974
1975 lock->force_write = 1;
1976 flag = log_all_ref_updates;
1977 log_all_ref_updates = 0;
1978 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1979 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1980 log_all_ref_updates = flag;
1981
1982 rollbacklog:
dfefa935 1983 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1984 error("unable to restore logfile %s from %s: %s",
dfefa935 1985 oldrefname, newrefname, strerror(errno));
c976d415 1986 if (!logmoved && log &&
dfefa935 1987 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1988 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1989 oldrefname, strerror(errno));
c976d415
LH
1990
1991 return 1;
1992}
1993
435fc852 1994int close_ref(struct ref_lock *lock)
b531394d
BC
1995{
1996 if (close_lock_file(lock->lk))
1997 return -1;
1998 lock->lock_fd = -1;
1999 return 0;
2000}
2001
435fc852 2002int commit_ref(struct ref_lock *lock)
b531394d
BC
2003{
2004 if (commit_lock_file(lock->lk))
2005 return -1;
2006 lock->lock_fd = -1;
2007 return 0;
2008}
2009
e5f38ec3 2010void unlock_ref(struct ref_lock *lock)
4bd18c43 2011{
4ed7cd3a
BC
2012 /* Do not free lock->lk -- atexit() still looks at them */
2013 if (lock->lk)
2014 rollback_lock_file(lock->lk);
434cd0cd 2015 free(lock->ref_name);
1655707c 2016 free(lock->orig_ref_name);
4bd18c43
SP
2017 free(lock);
2018}
2019
0ec29a47
JH
2020/*
2021 * copy the reflog message msg to buf, which has been allocated sufficiently
2022 * large, while cleaning up the whitespaces. Especially, convert LF to space,
2023 * because reflog file is one line per entry.
2024 */
2025static int copy_msg(char *buf, const char *msg)
2026{
2027 char *cp = buf;
2028 char c;
2029 int wasspace = 1;
2030
2031 *cp++ = '\t';
2032 while ((c = *msg++)) {
2033 if (wasspace && isspace(c))
2034 continue;
2035 wasspace = isspace(c);
2036 if (wasspace)
2037 c = ' ';
2038 *cp++ = c;
2039 }
2040 while (buf < cp && isspace(cp[-1]))
2041 cp--;
2042 *cp++ = '\n';
2043 return cp - buf;
2044}
2045
dfefa935 2046int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 2047{
859c3017 2048 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 2049
dfefa935 2050 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 2051 if (log_all_ref_updates &&
dfefa935
MH
2052 (!prefixcmp(refname, "refs/heads/") ||
2053 !prefixcmp(refname, "refs/remotes/") ||
2054 !prefixcmp(refname, "refs/notes/") ||
2055 !strcmp(refname, "HEAD"))) {
157aaea5 2056 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 2057 return error("unable to create directory for %s",
157aaea5 2058 logfile);
6de08ae6
SP
2059 oflags |= O_CREAT;
2060 }
2061
157aaea5 2062 logfd = open(logfile, oflags, 0666);
6de08ae6 2063 if (logfd < 0) {
1974bf62 2064 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 2065 return 0;
3b463c3f
JH
2066
2067 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 2068 if (remove_empty_directories(logfile)) {
3b463c3f 2069 return error("There are still logs under '%s'",
157aaea5 2070 logfile);
3b463c3f 2071 }
157aaea5 2072 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
2073 }
2074
2075 if (logfd < 0)
2076 return error("Unable to append to %s: %s",
157aaea5 2077 logfile, strerror(errno));
6de08ae6
SP
2078 }
2079
157aaea5 2080 adjust_shared_perm(logfile);
859c3017
EM
2081 close(logfd);
2082 return 0;
2083}
443b92b6 2084
dfefa935 2085static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
2086 const unsigned char *new_sha1, const char *msg)
2087{
2088 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2089 unsigned maxlen, len;
2090 int msglen;
157aaea5 2091 char log_file[PATH_MAX];
859c3017
EM
2092 char *logrec;
2093 const char *committer;
2094
2095 if (log_all_ref_updates < 0)
2096 log_all_ref_updates = !is_bare_repository();
2097
dfefa935 2098 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
2099 if (result)
2100 return result;
2101
2102 logfd = open(log_file, oflags);
2103 if (logfd < 0)
2104 return 0;
0ec29a47 2105 msglen = msg ? strlen(msg) : 0;
774751a8 2106 committer = git_committer_info(0);
8ac65937
JH
2107 maxlen = strlen(committer) + msglen + 100;
2108 logrec = xmalloc(maxlen);
2109 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
2110 sha1_to_hex(old_sha1),
2111 sha1_to_hex(new_sha1),
8ac65937
JH
2112 committer);
2113 if (msglen)
0ec29a47 2114 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 2115 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 2116 free(logrec);
91c8d590 2117 if (close(logfd) != 0 || written != len)
9a13f0b7 2118 return error("Unable to append to %s", log_file);
6de08ae6
SP
2119 return 0;
2120}
2121
c3b0dec5
LT
2122static int is_branch(const char *refname)
2123{
2124 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2125}
2126
4bd18c43
SP
2127int write_ref_sha1(struct ref_lock *lock,
2128 const unsigned char *sha1, const char *logmsg)
2129{
2130 static char term = '\n';
c3b0dec5 2131 struct object *o;
4bd18c43
SP
2132
2133 if (!lock)
95fc7512 2134 return -1;
a89fccd2 2135 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
2136 unlock_ref(lock);
2137 return 0;
95fc7512 2138 }
c3b0dec5
LT
2139 o = parse_object(sha1);
2140 if (!o) {
7be8b3ba 2141 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
2142 lock->ref_name, sha1_to_hex(sha1));
2143 unlock_ref(lock);
2144 return -1;
2145 }
2146 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2147 error("Trying to write non-commit object %s to branch %s",
2148 sha1_to_hex(sha1), lock->ref_name);
2149 unlock_ref(lock);
2150 return -1;
2151 }
93822c22
AW
2152 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2153 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 2154 || close_ref(lock) < 0) {
c33d5174 2155 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
2156 unlock_ref(lock);
2157 return -1;
2158 }
8bf90dc9 2159 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
2160 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2161 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2162 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
2163 unlock_ref(lock);
2164 return -1;
2165 }
605fac8b
NP
2166 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2167 /*
2168 * Special hack: If a branch is updated directly and HEAD
2169 * points to it (may happen on the remote side of a push
2170 * for example) then logically the HEAD reflog should be
2171 * updated too.
2172 * A generic solution implies reverse symref information,
2173 * but finding all symrefs pointing to the given branch
2174 * would be rather costly for this rare event (the direct
2175 * update of a branch) to be worth it. So let's cheat and
2176 * check with HEAD only which should cover 99% of all usage
2177 * scenarios (even 100% of the default ones).
2178 */
2179 unsigned char head_sha1[20];
2180 int head_flag;
2181 const char *head_ref;
8cad4744 2182 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
2183 if (head_ref && (head_flag & REF_ISSYMREF) &&
2184 !strcmp(head_ref, lock->ref_name))
2185 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2186 }
b531394d 2187 if (commit_ref(lock)) {
434cd0cd 2188 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
2189 unlock_ref(lock);
2190 return -1;
2191 }
4bd18c43
SP
2192 unlock_ref(lock);
2193 return 0;
95fc7512 2194}
d556fae2 2195
8b5157e4
NP
2196int create_symref(const char *ref_target, const char *refs_heads_master,
2197 const char *logmsg)
41b625b0
NP
2198{
2199 const char *lockpath;
2200 char ref[1000];
2201 int fd, len, written;
a4f34cbb 2202 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
2203 unsigned char old_sha1[20], new_sha1[20];
2204
2205 if (logmsg && read_ref(ref_target, old_sha1))
2206 hashclr(old_sha1);
41b625b0 2207
d48744d1
JH
2208 if (safe_create_leading_directories(git_HEAD) < 0)
2209 return error("unable to create directory for %s", git_HEAD);
2210
41b625b0
NP
2211#ifndef NO_SYMLINK_HEAD
2212 if (prefer_symlink_refs) {
2213 unlink(git_HEAD);
2214 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 2215 goto done;
41b625b0
NP
2216 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2217 }
2218#endif
2219
2220 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2221 if (sizeof(ref) <= len) {
2222 error("refname too long: %s", refs_heads_master);
47fc52e2 2223 goto error_free_return;
41b625b0
NP
2224 }
2225 lockpath = mkpath("%s.lock", git_HEAD);
2226 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2227 if (fd < 0) {
2228 error("Unable to open %s for writing", lockpath);
47fc52e2 2229 goto error_free_return;
41b625b0
NP
2230 }
2231 written = write_in_full(fd, ref, len);
91c8d590 2232 if (close(fd) != 0 || written != len) {
41b625b0 2233 error("Unable to write to %s", lockpath);
47fc52e2 2234 goto error_unlink_return;
41b625b0
NP
2235 }
2236 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 2237 error("Unable to create %s", git_HEAD);
47fc52e2 2238 goto error_unlink_return;
41b625b0
NP
2239 }
2240 if (adjust_shared_perm(git_HEAD)) {
41b625b0 2241 error("Unable to fix permissions on %s", lockpath);
47fc52e2 2242 error_unlink_return:
691f1a28 2243 unlink_or_warn(lockpath);
47fc52e2
JH
2244 error_free_return:
2245 free(git_HEAD);
2246 return -1;
41b625b0 2247 }
8b5157e4 2248
ee96d11b 2249#ifndef NO_SYMLINK_HEAD
8b5157e4 2250 done:
ee96d11b 2251#endif
8b5157e4
NP
2252 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2253 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2254
47fc52e2 2255 free(git_HEAD);
41b625b0
NP
2256 return 0;
2257}
2258
16d7cc90
JH
2259static char *ref_msg(const char *line, const char *endp)
2260{
2261 const char *ep;
16d7cc90 2262 line += 82;
182af834
PH
2263 ep = memchr(line, '\n', endp - line);
2264 if (!ep)
2265 ep = endp;
2266 return xmemdupz(line, ep - line);
16d7cc90
JH
2267}
2268
dfefa935
MH
2269int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2270 unsigned char *sha1, char **msg,
2271 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 2272{
e5229042 2273 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 2274 char *tz_c;
e29cb53a 2275 int logfd, tz, reccnt = 0;
d556fae2
SP
2276 struct stat st;
2277 unsigned long date;
e5229042 2278 unsigned char logged_sha1[20];
cb48cb58 2279 void *log_mapped;
dc49cd76 2280 size_t mapsz;
d556fae2 2281
dfefa935 2282 logfile = git_path("logs/%s", refname);
d556fae2
SP
2283 logfd = open(logfile, O_RDONLY, 0);
2284 if (logfd < 0)
d824cbba 2285 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
2286 fstat(logfd, &st);
2287 if (!st.st_size)
2288 die("Log %s is empty.", logfile);
dc49cd76
SP
2289 mapsz = xsize_t(st.st_size);
2290 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 2291 logdata = log_mapped;
d556fae2
SP
2292 close(logfd);
2293
e5229042 2294 lastrec = NULL;
d556fae2
SP
2295 rec = logend = logdata + st.st_size;
2296 while (logdata < rec) {
e29cb53a 2297 reccnt++;
d556fae2
SP
2298 if (logdata < rec && *(rec-1) == '\n')
2299 rec--;
e5229042
SP
2300 lastgt = NULL;
2301 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 2302 rec--;
e5229042
SP
2303 if (*rec == '>')
2304 lastgt = rec;
2305 }
2306 if (!lastgt)
d556fae2 2307 die("Log %s is corrupt.", logfile);
e5229042 2308 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 2309 if (date <= at_time || cnt == 0) {
76a44c5c 2310 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
2311 if (msg)
2312 *msg = ref_msg(rec, logend);
2313 if (cutoff_time)
2314 *cutoff_time = date;
2315 if (cutoff_tz)
2316 *cutoff_tz = tz;
2317 if (cutoff_cnt)
76a44c5c 2318 *cutoff_cnt = reccnt - 1;
e5229042
SP
2319 if (lastrec) {
2320 if (get_sha1_hex(lastrec, logged_sha1))
2321 die("Log %s is corrupt.", logfile);
2322 if (get_sha1_hex(rec + 41, sha1))
2323 die("Log %s is corrupt.", logfile);
a89fccd2 2324 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2325 warning("Log %s has gap after %s.",
73013afd 2326 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 2327 }
e5f38ec3
JH
2328 }
2329 else if (date == at_time) {
e5229042
SP
2330 if (get_sha1_hex(rec + 41, sha1))
2331 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
2332 }
2333 else {
e5229042
SP
2334 if (get_sha1_hex(rec + 41, logged_sha1))
2335 die("Log %s is corrupt.", logfile);
a89fccd2 2336 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 2337 warning("Log %s unexpectedly ended on %s.",
73013afd 2338 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
2339 }
2340 }
dc49cd76 2341 munmap(log_mapped, mapsz);
d556fae2
SP
2342 return 0;
2343 }
e5229042 2344 lastrec = rec;
ab2a1a32
JH
2345 if (cnt > 0)
2346 cnt--;
d556fae2
SP
2347 }
2348
e5229042
SP
2349 rec = logdata;
2350 while (rec < logend && *rec != '>' && *rec != '\n')
2351 rec++;
2352 if (rec == logend || *rec == '\n')
d556fae2 2353 die("Log %s is corrupt.", logfile);
e5229042 2354 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
2355 tz = strtoul(tz_c, NULL, 10);
2356 if (get_sha1_hex(logdata, sha1))
2357 die("Log %s is corrupt.", logfile);
d1a4489a
JK
2358 if (is_null_sha1(sha1)) {
2359 if (get_sha1_hex(logdata + 41, sha1))
2360 die("Log %s is corrupt.", logfile);
2361 }
16d7cc90
JH
2362 if (msg)
2363 *msg = ref_msg(logdata, logend);
dc49cd76 2364 munmap(log_mapped, mapsz);
16d7cc90
JH
2365
2366 if (cutoff_time)
2367 *cutoff_time = date;
2368 if (cutoff_tz)
2369 *cutoff_tz = tz;
2370 if (cutoff_cnt)
2371 *cutoff_cnt = reccnt;
2372 return 1;
d556fae2 2373}
2ff81662 2374
dfefa935 2375int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
2376{
2377 const char *logfile;
2378 FILE *logfp;
8ca78803 2379 struct strbuf sb = STRBUF_INIT;
2266bf27 2380 int ret = 0;
2ff81662 2381
dfefa935 2382 logfile = git_path("logs/%s", refname);
2ff81662
JH
2383 logfp = fopen(logfile, "r");
2384 if (!logfp)
883d60fa 2385 return -1;
101d15e0
JH
2386
2387 if (ofs) {
2388 struct stat statbuf;
2389 if (fstat(fileno(logfp), &statbuf) ||
2390 statbuf.st_size < ofs ||
2391 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 2392 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 2393 fclose(logfp);
8ca78803 2394 strbuf_release(&sb);
101d15e0 2395 return -1;
9d33f7c2 2396 }
101d15e0
JH
2397 }
2398
8ca78803 2399 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 2400 unsigned char osha1[20], nsha1[20];
883d60fa
JS
2401 char *email_end, *message;
2402 unsigned long timestamp;
8ca78803 2403 int tz;
2ff81662
JH
2404
2405 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
2406 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2407 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2408 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2409 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
2410 email_end[1] != ' ' ||
2411 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2412 !message || message[0] != ' ' ||
2413 (message[1] != '+' && message[1] != '-') ||
2414 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2415 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2416 continue; /* corrupt? */
883d60fa
JS
2417 email_end[1] = '\0';
2418 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2419 if (message[6] != '\t')
2420 message += 6;
2421 else
2422 message += 7;
8ca78803
RS
2423 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2424 cb_data);
883d60fa 2425 if (ret)
2266bf27 2426 break;
2ff81662
JH
2427 }
2428 fclose(logfp);
8ca78803 2429 strbuf_release(&sb);
2266bf27 2430 return ret;
2ff81662 2431}
e29cb53a 2432
dfefa935 2433int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2434{
dfefa935 2435 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2436}
2437
989c0e5d
MH
2438/*
2439 * Call fn for each reflog in the namespace indicated by name. name
2440 * must be empty or end with '/'. Name will be used as a scratch
2441 * space, but its contents will be restored before return.
2442 */
2443static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
eb8381c8 2444{
989c0e5d 2445 DIR *d = opendir(git_path("logs/%s", name->buf));
fcee5a14 2446 int retval = 0;
93c603fc 2447 struct dirent *de;
989c0e5d 2448 int oldlen = name->len;
eb8381c8 2449
93c603fc 2450 if (!d)
989c0e5d 2451 return name->len ? errno : 0;
eb8381c8 2452
93c603fc
MH
2453 while ((de = readdir(d)) != NULL) {
2454 struct stat st;
eb8381c8 2455
93c603fc
MH
2456 if (de->d_name[0] == '.')
2457 continue;
93c603fc
MH
2458 if (has_extension(de->d_name, ".lock"))
2459 continue;
989c0e5d
MH
2460 strbuf_addstr(name, de->d_name);
2461 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2462 ; /* silently ignore */
93c603fc 2463 } else {
eb8381c8 2464 if (S_ISDIR(st.st_mode)) {
989c0e5d
MH
2465 strbuf_addch(name, '/');
2466 retval = do_for_each_reflog(name, fn, cb_data);
eb8381c8
NP
2467 } else {
2468 unsigned char sha1[20];
989c0e5d
MH
2469 if (read_ref_full(name->buf, sha1, 0, NULL))
2470 retval = error("bad ref for %s", name->buf);
eb8381c8 2471 else
989c0e5d 2472 retval = fn(name->buf, sha1, 0, cb_data);
eb8381c8
NP
2473 }
2474 if (retval)
2475 break;
2476 }
989c0e5d 2477 strbuf_setlen(name, oldlen);
eb8381c8 2478 }
93c603fc 2479 closedir(d);
eb8381c8
NP
2480 return retval;
2481}
2482
2483int for_each_reflog(each_ref_fn fn, void *cb_data)
2484{
989c0e5d
MH
2485 int retval;
2486 struct strbuf name;
2487 strbuf_init(&name, PATH_MAX);
2488 retval = do_for_each_reflog(&name, fn, cb_data);
2489 strbuf_release(&name);
2490 return retval;
eb8381c8 2491}
3d9f037c
CR
2492
2493int update_ref(const char *action, const char *refname,
2494 const unsigned char *sha1, const unsigned char *oldval,
2495 int flags, enum action_on_err onerr)
2496{
2497 static struct ref_lock *lock;
2498 lock = lock_any_ref_for_update(refname, oldval, flags);
2499 if (!lock) {
2500 const char *str = "Cannot lock the ref '%s'.";
2501 switch (onerr) {
2502 case MSG_ON_ERR: error(str, refname); break;
2503 case DIE_ON_ERR: die(str, refname); break;
2504 case QUIET_ON_ERR: break;
2505 }
2506 return 1;
2507 }
2508 if (write_ref_sha1(lock, sha1, action) < 0) {
2509 const char *str = "Cannot update the ref '%s'.";
2510 switch (onerr) {
2511 case MSG_ON_ERR: error(str, refname); break;
2512 case DIE_ON_ERR: die(str, refname); break;
2513 case QUIET_ON_ERR: break;
2514 }
2515 return 1;
2516 }
2517 return 0;
2518}
cda69f48 2519
5483f799 2520struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2521{
2522 for ( ; list; list = list->next)
2523 if (!strcmp(list->name, name))
5483f799 2524 return (struct ref *)list;
cda69f48
JK
2525 return NULL;
2526}
7c2b3029
JK
2527
2528/*
2529 * generate a format suitable for scanf from a ref_rev_parse_rules
2530 * rule, that is replace the "%.*s" spec with a "%s" spec
2531 */
2532static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2533{
2534 char *spec;
2535
2536 spec = strstr(rule, "%.*s");
2537 if (!spec || strstr(spec + 4, "%.*s"))
2538 die("invalid rule in ref_rev_parse_rules: %s", rule);
2539
2540 /* copy all until spec */
2541 strncpy(scanf_fmt, rule, spec - rule);
2542 scanf_fmt[spec - rule] = '\0';
2543 /* copy new spec */
2544 strcat(scanf_fmt, "%s");
2545 /* copy remaining rule */
2546 strcat(scanf_fmt, spec + 4);
2547
2548 return;
2549}
2550
dfefa935 2551char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2552{
2553 int i;
2554 static char **scanf_fmts;
2555 static int nr_rules;
2556 char *short_name;
2557
2558 /* pre generate scanf formats from ref_rev_parse_rules[] */
2559 if (!nr_rules) {
2560 size_t total_len = 0;
2561
2562 /* the rule list is NULL terminated, count them first */
2563 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2564 /* no +1 because strlen("%s") < strlen("%.*s") */
2565 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2566
2567 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2568
2569 total_len = 0;
2570 for (i = 0; i < nr_rules; i++) {
2571 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2572 + total_len;
2573 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2574 total_len += strlen(ref_rev_parse_rules[i]);
2575 }
2576 }
2577
2578 /* bail out if there are no rules */
2579 if (!nr_rules)
dfefa935 2580 return xstrdup(refname);
7c2b3029 2581
dfefa935
MH
2582 /* buffer for scanf result, at most refname must fit */
2583 short_name = xstrdup(refname);
7c2b3029
JK
2584
2585 /* skip first rule, it will always match */
2586 for (i = nr_rules - 1; i > 0 ; --i) {
2587 int j;
6e7b3309 2588 int rules_to_fail = i;
7c2b3029
JK
2589 int short_name_len;
2590
dfefa935 2591 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2592 continue;
2593
2594 short_name_len = strlen(short_name);
2595
6e7b3309
BW
2596 /*
2597 * in strict mode, all (except the matched one) rules
2598 * must fail to resolve to a valid non-ambiguous ref
2599 */
2600 if (strict)
2601 rules_to_fail = nr_rules;
2602
7c2b3029
JK
2603 /*
2604 * check if the short name resolves to a valid ref,
2605 * but use only rules prior to the matched one
2606 */
6e7b3309 2607 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2608 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2609 char refname[PATH_MAX];
2610
6e7b3309
BW
2611 /* skip matched rule */
2612 if (i == j)
2613 continue;
2614
7c2b3029
JK
2615 /*
2616 * the short name is ambiguous, if it resolves
2617 * (with this previous rule) to a valid ref
2618 * read_ref() returns 0 on success
2619 */
2620 mksnpath(refname, sizeof(refname),
2621 rule, short_name_len, short_name);
c6893323 2622 if (ref_exists(refname))
7c2b3029
JK
2623 break;
2624 }
2625
2626 /*
2627 * short name is non-ambiguous if all previous rules
2628 * haven't resolved to a valid ref
2629 */
6e7b3309 2630 if (j == rules_to_fail)
7c2b3029
JK
2631 return short_name;
2632 }
2633
2634 free(short_name);
dfefa935 2635 return xstrdup(refname);
7c2b3029 2636}