refs.c: rename ref_array -> ref_dir
[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
593f1bb8
MH
104struct ref_value {
105 unsigned char sha1[20];
106 unsigned char peeled[20];
107};
108
d3177275 109struct ref_dir {
e9c4c111 110 int nr, alloc;
e6ed3ca6
MH
111
112 /*
113 * Entries with index 0 <= i < sorted are sorted by name. New
114 * entries are appended to the list unsorted, and are sorted
115 * only when required; thus we avoid the need to sort the list
116 * after the addition of every reference.
117 */
118 int sorted;
119
d3177275 120 struct ref_entry **entries;
e9c4c111
JP
121};
122
bc5fd6d3
MH
123/* ISSYMREF=0x01, ISPACKED=0x02 and ISBROKEN=0x04 are public interfaces */
124#define REF_KNOWS_PEELED 0x10
cf0adba7 125
bc5fd6d3
MH
126struct ref_entry {
127 unsigned char flag; /* ISSYMREF? ISPACKED? */
593f1bb8
MH
128 union {
129 struct ref_value value;
130 } u;
bc5fd6d3
MH
131 /* The full name of the reference (e.g., "refs/heads/master"): */
132 char name[FLEX_ARRAY];
133};
e1e22e37 134
cddc4258
MH
135static struct ref_entry *create_ref_entry(const char *refname,
136 const unsigned char *sha1, int flag,
137 int check_name)
e1e22e37
LT
138{
139 int len;
cddc4258 140 struct ref_entry *ref;
e1e22e37 141
09116a1c 142 if (check_name &&
dfefa935
MH
143 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
144 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
145 len = strlen(refname) + 1;
146 ref = xmalloc(sizeof(struct ref_entry) + len);
593f1bb8
MH
147 hashcpy(ref->u.value.sha1, sha1);
148 hashclr(ref->u.value.peeled);
cddc4258
MH
149 memcpy(ref->name, refname, len);
150 ref->flag = flag;
151 return ref;
152}
153
732134ed
MH
154static void free_ref_entry(struct ref_entry *entry)
155{
156 free(entry);
157}
158
d3177275
MH
159/* Add a ref_entry to the end of the ref_dir (unsorted). */
160static void add_ref(struct ref_dir *refs, struct ref_entry *ref)
cddc4258 161{
d3177275
MH
162 ALLOC_GROW(refs->entries, refs->nr + 1, refs->alloc);
163 refs->entries[refs->nr++] = ref;
c774aab9
JP
164}
165
d3177275 166static void clear_ref_dir(struct ref_dir *dir)
bc5fd6d3
MH
167{
168 int i;
d3177275
MH
169 for (i = 0; i < dir->nr; i++)
170 free_ref_entry(dir->entries[i]);
171 free(dir->entries);
172 dir->sorted = dir->nr = dir->alloc = 0;
173 dir->entries = NULL;
bc5fd6d3
MH
174}
175
e9c4c111 176static int ref_entry_cmp(const void *a, const void *b)
c774aab9 177{
e9c4c111
JP
178 struct ref_entry *one = *(struct ref_entry **)a;
179 struct ref_entry *two = *(struct ref_entry **)b;
180 return strcmp(one->name, two->name);
181}
c774aab9 182
d3177275 183static void sort_ref_dir(struct ref_dir *dir);
bc5fd6d3 184
d3177275 185static struct ref_entry *search_ref_dir(struct ref_dir *dir, const char *refname)
bc5fd6d3
MH
186{
187 struct ref_entry *e, **r;
188 int len;
189
190 if (refname == NULL)
191 return NULL;
192
d3177275 193 if (!dir->nr)
bc5fd6d3 194 return NULL;
d3177275 195 sort_ref_dir(dir);
bc5fd6d3
MH
196 len = strlen(refname) + 1;
197 e = xmalloc(sizeof(struct ref_entry) + len);
198 memcpy(e->name, refname, len);
199
d3177275 200 r = bsearch(&e, dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
bc5fd6d3
MH
201
202 free(e);
203
204 if (r == NULL)
205 return NULL;
206
207 return *r;
208}
209
202a56a9
MH
210/*
211 * Emit a warning and return true iff ref1 and ref2 have the same name
212 * and the same sha1. Die if they have the same name but different
213 * sha1s.
214 */
215static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
216{
217 if (!strcmp(ref1->name, ref2->name)) {
218 /* Duplicate name; make sure that the SHA1s match: */
593f1bb8 219 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
202a56a9
MH
220 die("Duplicated ref, and SHA1s don't match: %s",
221 ref1->name);
222 warning("Duplicated ref: %s", ref1->name);
223 return 1;
224 } else {
225 return 0;
226 }
227}
228
e6ed3ca6 229/*
d3177275 230 * Sort the entries in dir (if they are not already sorted).
e6ed3ca6 231 */
d3177275 232static void sort_ref_dir(struct ref_dir *dir)
e9c4c111 233{
202a56a9 234 int i, j;
c774aab9 235
e6ed3ca6
MH
236 /*
237 * This check also prevents passing a zero-length array to qsort(),
238 * which is a problem on some platforms.
239 */
d3177275 240 if (dir->sorted == dir->nr)
e9c4c111 241 return;
c774aab9 242
d3177275 243 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
c774aab9 244
d3177275 245 /* Remove any duplicates from the ref_dir */
202a56a9 246 i = 0;
d3177275
MH
247 for (j = 1; j < dir->nr; j++) {
248 if (is_dup_ref(dir->entries[i], dir->entries[j])) {
249 free_ref_entry(dir->entries[j]);
e9c4c111
JP
250 continue;
251 }
d3177275 252 dir->entries[++i] = dir->entries[j];
e9c4c111 253 }
d3177275 254 dir->sorted = dir->nr = i + 1;
e9c4c111 255}
c774aab9 256
bc5fd6d3 257#define DO_FOR_EACH_INCLUDE_BROKEN 01
c774aab9 258
bc5fd6d3 259static struct ref_entry *current_ref;
c774aab9 260
bc5fd6d3
MH
261static int do_one_ref(const char *base, each_ref_fn fn, int trim,
262 int flags, void *cb_data, struct ref_entry *entry)
263{
429213e4 264 int retval;
bc5fd6d3
MH
265 if (prefixcmp(entry->name, base))
266 return 0;
c774aab9 267
bc5fd6d3
MH
268 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
269 if (entry->flag & REF_ISBROKEN)
270 return 0; /* ignore broken refs e.g. dangling symref */
593f1bb8 271 if (!has_sha1_file(entry->u.value.sha1)) {
bc5fd6d3
MH
272 error("%s does not point to a valid object!", entry->name);
273 return 0;
274 }
275 }
276 current_ref = entry;
593f1bb8 277 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
429213e4
MH
278 current_ref = NULL;
279 return retval;
bc5fd6d3 280}
c774aab9 281
c36b5bc2 282/*
d3177275
MH
283 * Call fn for each reference in dir that has index in the range
284 * offset <= index < dir->nr. This function does not sort the dir;
285 * sorting should be done by the caller.
c36b5bc2 286 */
d3177275
MH
287static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
288 const char *base,
289 each_ref_fn fn, int trim, int flags, void *cb_data)
c36b5bc2
MH
290{
291 int i;
d3177275
MH
292 assert(dir->sorted == dir->nr);
293 for (i = offset; i < dir->nr; i++) {
294 int retval = do_one_ref(base, fn, trim, flags, cb_data, dir->entries[i]);
c36b5bc2
MH
295 if (retval)
296 return retval;
297 }
298 return 0;
299}
300
b3fd060f 301/*
d3177275
MH
302 * Call fn for each reference in the union of dir1 and dir2, in order
303 * by refname. If an entry appears in both dir1 and dir2, then only
304 * process the version that is in dir2. The input dirs must already
305 * be sorted.
b3fd060f 306 */
d3177275
MH
307static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
308 struct ref_dir *dir2,
309 const char *base, each_ref_fn fn, int trim,
310 int flags, void *cb_data)
b3fd060f
MH
311{
312 int retval;
313 int i1 = 0, i2 = 0;
314
d3177275
MH
315 assert(dir1->sorted == dir1->nr);
316 assert(dir2->sorted == dir2->nr);
317 while (i1 < dir1->nr && i2 < dir2->nr) {
318 struct ref_entry *e1 = dir1->entries[i1];
319 struct ref_entry *e2 = dir2->entries[i2];
b3fd060f
MH
320 int cmp = strcmp(e1->name, e2->name);
321 if (cmp < 0) {
322 retval = do_one_ref(base, fn, trim, flags, cb_data, e1);
323 i1++;
324 } else {
325 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
326 i2++;
327 if (cmp == 0) {
328 /*
329 * There was a ref in array1 with the
330 * same name; ignore it.
331 */
332 i1++;
333 }
334 }
335 if (retval)
336 return retval;
337 }
d3177275
MH
338 if (i1 < dir1->nr)
339 return do_for_each_ref_in_dir(dir1, i1,
340 base, fn, trim, flags, cb_data);
341 if (i2 < dir2->nr)
342 return do_for_each_ref_in_dir(dir2, i2,
343 base, fn, trim, flags, cb_data);
b3fd060f
MH
344 return 0;
345}
346
d66da478
MH
347/*
348 * Return true iff refname1 and refname2 conflict with each other.
349 * Two reference names conflict if one of them exactly matches the
350 * leading components of the other; e.g., "foo/bar" conflicts with
351 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
352 * "foo/barbados".
353 */
354static int names_conflict(const char *refname1, const char *refname2)
355{
5a4d4947
MH
356 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
357 ;
358 return (*refname1 == '\0' && *refname2 == '/')
359 || (*refname1 == '/' && *refname2 == '\0');
360}
361
362struct name_conflict_cb {
363 const char *refname;
364 const char *oldrefname;
365 const char *conflicting_refname;
366};
367
368static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
369 int flags, void *cb_data)
370{
371 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
372 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
373 return 0;
374 if (names_conflict(data->refname, existingrefname)) {
375 data->conflicting_refname = existingrefname;
376 return 1;
d66da478 377 }
5a4d4947 378 return 0;
d66da478
MH
379}
380
bc5fd6d3
MH
381/*
382 * Return true iff a reference named refname could be created without
5a4d4947
MH
383 * conflicting with the name of an existing reference in array. If
384 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
385 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
386 * operation).
387 */
388static int is_refname_available(const char *refname, const char *oldrefname,
d3177275 389 struct ref_dir *dir)
bc5fd6d3 390{
5a4d4947
MH
391 struct name_conflict_cb data;
392 data.refname = refname;
393 data.oldrefname = oldrefname;
394 data.conflicting_refname = NULL;
395
d3177275
MH
396 sort_ref_dir(dir);
397 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
398 0, DO_FOR_EACH_INCLUDE_BROKEN,
399 &data)) {
5a4d4947
MH
400 error("'%s' exists; cannot create '%s'",
401 data.conflicting_refname, refname);
402 return 0;
bc5fd6d3
MH
403 }
404 return 1;
e1e22e37
LT
405}
406
5e290ff7
JH
407/*
408 * Future: need to be in "struct repository"
409 * when doing a full libification.
410 */
79c7ca54
MH
411static struct ref_cache {
412 struct ref_cache *next;
5e290ff7
JH
413 char did_loose;
414 char did_packed;
d3177275
MH
415 struct ref_dir loose;
416 struct ref_dir packed;
ce40979c
MH
417 /* The submodule name, or "" for the main repo. */
418 char name[FLEX_ARRAY];
79c7ca54 419} *ref_cache;
0e88c130 420
760c4512 421static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 422{
1b7edaf9 423 if (refs->did_packed)
d3177275 424 clear_ref_dir(&refs->packed);
760c4512 425 refs->did_packed = 0;
5e290ff7 426}
e1e22e37 427
760c4512
MH
428static void clear_loose_ref_cache(struct ref_cache *refs)
429{
430 if (refs->did_loose)
d3177275 431 clear_ref_dir(&refs->loose);
760c4512
MH
432 refs->did_loose = 0;
433}
434
79c7ca54 435static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 436{
ce40979c 437 int len;
79c7ca54 438 struct ref_cache *refs;
ce40979c
MH
439 if (!submodule)
440 submodule = "";
441 len = strlen(submodule) + 1;
79c7ca54 442 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 443 memcpy(refs->name, submodule, len);
e5dbf605
MH
444 return refs;
445}
446
4349a668 447/*
79c7ca54 448 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
449 * the main repository, use submodule==NULL. The returned structure
450 * will be allocated and initialized but not necessarily populated; it
451 * should not be freed.
452 */
79c7ca54 453static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 454{
79c7ca54 455 struct ref_cache *refs = ref_cache;
0e88c130
MH
456 if (!submodule)
457 submodule = "";
458 while (refs) {
459 if (!strcmp(submodule, refs->name))
460 return refs;
461 refs = refs->next;
4349a668 462 }
0e88c130 463
79c7ca54
MH
464 refs = create_ref_cache(submodule);
465 refs->next = ref_cache;
466 ref_cache = refs;
0e88c130 467 return refs;
4349a668
MH
468}
469
8be8bde7 470void invalidate_ref_cache(const char *submodule)
f130b116 471{
c5f29abd
MH
472 struct ref_cache *refs = get_ref_cache(submodule);
473 clear_packed_ref_cache(refs);
474 clear_loose_ref_cache(refs);
5e290ff7 475}
e1e22e37 476
bc5fd6d3
MH
477/*
478 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
479 * Return a pointer to the refname within the line (null-terminated),
480 * or NULL if there was a problem.
481 */
482static const char *parse_ref_line(char *line, unsigned char *sha1)
483{
484 /*
485 * 42: the answer to everything.
486 *
487 * In this case, it happens to be the answer to
488 * 40 (length of sha1 hex representation)
489 * +1 (space in between hex and name)
490 * +1 (newline at the end of the line)
491 */
492 int len = strlen(line) - 42;
493
494 if (len <= 0)
495 return NULL;
496 if (get_sha1_hex(line, sha1) < 0)
497 return NULL;
498 if (!isspace(line[40]))
499 return NULL;
500 line += 41;
501 if (isspace(*line))
502 return NULL;
503 if (line[len] != '\n')
504 return NULL;
505 line[len] = 0;
506
507 return line;
508}
509
d3177275 510static void read_packed_refs(FILE *f, struct ref_dir *dir)
f4204ab9 511{
e9c4c111 512 struct ref_entry *last = NULL;
f4204ab9
JH
513 char refline[PATH_MAX];
514 int flag = REF_ISPACKED;
515
516 while (fgets(refline, sizeof(refline), f)) {
517 unsigned char sha1[20];
dfefa935 518 const char *refname;
f4204ab9
JH
519 static const char header[] = "# pack-refs with:";
520
521 if (!strncmp(refline, header, sizeof(header)-1)) {
522 const char *traits = refline + sizeof(header) - 1;
523 if (strstr(traits, " peeled "))
524 flag |= REF_KNOWS_PEELED;
525 /* perhaps other traits later as well */
526 continue;
527 }
528
dfefa935
MH
529 refname = parse_ref_line(refline, sha1);
530 if (refname) {
dd73ecd1 531 last = create_ref_entry(refname, sha1, flag, 1);
d3177275 532 add_ref(dir, last);
f4204ab9
JH
533 continue;
534 }
535 if (last &&
536 refline[0] == '^' &&
537 strlen(refline) == 42 &&
538 refline[41] == '\n' &&
539 !get_sha1_hex(refline + 1, sha1))
593f1bb8 540 hashcpy(last->u.value.peeled, sha1);
f4204ab9 541 }
f4204ab9
JH
542}
543
d3177275 544static struct ref_dir *get_packed_refs(struct ref_cache *refs)
5e290ff7 545{
4349a668
MH
546 if (!refs->did_packed) {
547 const char *packed_refs_file;
548 FILE *f;
0bad611b 549
316b097a
MH
550 if (*refs->name)
551 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
552 else
553 packed_refs_file = git_path("packed-refs");
554 f = fopen(packed_refs_file, "r");
e1e22e37 555 if (f) {
2c5c66be 556 read_packed_refs(f, &refs->packed);
e1e22e37 557 fclose(f);
e1e22e37 558 }
0bad611b 559 refs->did_packed = 1;
e1e22e37 560 }
e9c4c111 561 return &refs->packed;
e1e22e37
LT
562}
563
30249ee6
MH
564void add_packed_ref(const char *refname, const unsigned char *sha1)
565{
566 add_ref(get_packed_refs(get_ref_cache(NULL)),
567 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
568}
569
3b124823 570static void get_ref_dir(struct ref_cache *refs, const char *base,
d3177275 571 struct ref_dir *dir)
e1e22e37 572{
d3177275 573 DIR *d;
0bad611b
HV
574 const char *path;
575
3b124823
MH
576 if (*refs->name)
577 path = git_path_submodule(refs->name, "%s", base);
0bad611b
HV
578 else
579 path = git_path("%s", base);
580
d3177275
MH
581 d = opendir(path);
582 if (d) {
e1e22e37
LT
583 struct dirent *de;
584 int baselen = strlen(base);
dfefa935 585 char *refname = xmalloc(baselen + 257);
e1e22e37 586
dfefa935 587 memcpy(refname, base, baselen);
e1e22e37 588 if (baselen && base[baselen-1] != '/')
dfefa935 589 refname[baselen++] = '/';
e1e22e37 590
d3177275 591 while ((de = readdir(d)) != NULL) {
e1e22e37
LT
592 unsigned char sha1[20];
593 struct stat st;
8da19775 594 int flag;
e1e22e37 595 int namelen;
0bad611b 596 const char *refdir;
e1e22e37
LT
597
598 if (de->d_name[0] == '.')
599 continue;
600 namelen = strlen(de->d_name);
601 if (namelen > 255)
602 continue;
603 if (has_extension(de->d_name, ".lock"))
604 continue;
dfefa935 605 memcpy(refname + baselen, de->d_name, namelen+1);
3b124823
MH
606 refdir = *refs->name
607 ? git_path_submodule(refs->name, "%s", refname)
dfefa935 608 : git_path("%s", refname);
0bad611b 609 if (stat(refdir, &st) < 0)
e1e22e37
LT
610 continue;
611 if (S_ISDIR(st.st_mode)) {
d3177275 612 get_ref_dir(refs, refname, dir);
e1e22e37
LT
613 continue;
614 }
3b124823 615 if (*refs->name) {
f8948e2f 616 hashclr(sha1);
0bad611b 617 flag = 0;
3b124823 618 if (resolve_gitlink_ref(refs->name, refname, sha1) < 0) {
0bad611b 619 hashclr(sha1);
98ac34b2 620 flag |= REF_ISBROKEN;
0bad611b 621 }
dfefa935 622 } else if (read_ref_full(refname, sha1, 1, &flag)) {
09116a1c
JH
623 hashclr(sha1);
624 flag |= REF_ISBROKEN;
625 }
d3177275 626 add_ref(dir, create_ref_entry(refname, sha1, flag, 1));
e1e22e37 627 }
dfefa935 628 free(refname);
d3177275 629 closedir(d);
e1e22e37 630 }
e1e22e37
LT
631}
632
d3177275 633static struct ref_dir *get_loose_refs(struct ref_cache *refs)
e1e22e37 634{
4349a668 635 if (!refs->did_loose) {
3b124823 636 get_ref_dir(refs, "refs", &refs->loose);
4349a668 637 refs->did_loose = 1;
e1e22e37 638 }
2c5c66be 639 return &refs->loose;
e1e22e37
LT
640}
641
ca8db142
LT
642/* We allow "recursive" symbolic refs. Only within reason, though */
643#define MAXDEPTH 5
0ebde32c
LT
644#define MAXREFLEN (1024)
645
e5fa45c1
JH
646/*
647 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
648 * from the loose refs in ref_cache refs. Find <refname> in the
649 * packed-refs file for the submodule.
e5fa45c1 650 */
b0626608 651static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 652 const char *refname, unsigned char *sha1)
0ebde32c 653{
2c5c66be 654 struct ref_entry *ref;
d3177275 655 struct ref_dir *dir = get_packed_refs(refs);
0ebde32c 656
d3177275 657 ref = search_ref_dir(dir, refname);
b0626608
MH
658 if (ref == NULL)
659 return -1;
660
593f1bb8 661 memcpy(sha1, ref->u.value.sha1, 20);
b0626608 662 return 0;
0ebde32c
LT
663}
664
b0626608 665static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 666 const char *refname, unsigned char *sha1,
dfefa935 667 int recursion)
0ebde32c 668{
064d51dc 669 int fd, len;
0ebde32c 670 char buffer[128], *p;
064d51dc 671 char *path;
0ebde32c 672
064d51dc 673 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 674 return -1;
064d51dc
MH
675 path = *refs->name
676 ? git_path_submodule(refs->name, "%s", refname)
677 : git_path("%s", refname);
678 fd = open(path, O_RDONLY);
0ebde32c 679 if (fd < 0)
b0626608 680 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
681
682 len = read(fd, buffer, sizeof(buffer)-1);
683 close(fd);
684 if (len < 0)
685 return -1;
686 while (len && isspace(buffer[len-1]))
687 len--;
688 buffer[len] = 0;
689
690 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 691 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
692 return 0;
693
694 /* Symref? */
695 if (strncmp(buffer, "ref:", 4))
696 return -1;
697 p = buffer + 4;
698 while (isspace(*p))
699 p++;
700
064d51dc 701 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
702}
703
85be1fe3 704int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
705{
706 int len = strlen(path), retval;
064d51dc 707 char *submodule;
b0626608 708 struct ref_cache *refs;
0ebde32c
LT
709
710 while (len && path[len-1] == '/')
711 len--;
712 if (!len)
713 return -1;
b0626608
MH
714 submodule = xstrndup(path, len);
715 refs = get_ref_cache(submodule);
716 free(submodule);
717
064d51dc 718 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
719 return retval;
720}
ca8db142 721
4886b89f 722/*
c224ca7f
MH
723 * Try to read ref from the packed references. On success, set sha1
724 * and return 0; otherwise, return -1.
4886b89f 725 */
dfefa935 726static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 727{
d3177275
MH
728 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
729 struct ref_entry *entry = search_ref_dir(packed, refname);
2c5c66be 730 if (entry) {
593f1bb8 731 hashcpy(sha1, entry->u.value.sha1);
2c5c66be 732 return 0;
c224ca7f
MH
733 }
734 return -1;
735}
736
8d68493f 737const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 738{
0104ca09
HO
739 int depth = MAXDEPTH;
740 ssize_t len;
a876ed83 741 char buffer[256];
dfefa935 742 static char refname_buffer[256];
ca8db142 743
8da19775
JH
744 if (flag)
745 *flag = 0;
746
dfefa935 747 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
748 return NULL;
749
a876ed83 750 for (;;) {
55956350 751 char path[PATH_MAX];
a876ed83
JH
752 struct stat st;
753 char *buf;
754 int fd;
8a65ff76 755
a876ed83
JH
756 if (--depth < 0)
757 return NULL;
ca8db142 758
dfefa935 759 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 760
a876ed83 761 if (lstat(path, &st) < 0) {
c224ca7f
MH
762 if (errno != ENOENT)
763 return NULL;
764 /*
765 * The loose reference file does not exist;
766 * check for a packed reference.
767 */
dfefa935 768 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
769 if (flag)
770 *flag |= REF_ISPACKED;
dfefa935 771 return refname;
434cd0cd 772 }
c224ca7f
MH
773 /* The reference is not a packed reference, either. */
774 if (reading) {
a876ed83 775 return NULL;
c224ca7f
MH
776 } else {
777 hashclr(sha1);
dfefa935 778 return refname;
c224ca7f 779 }
a876ed83 780 }
ca8db142 781
a876ed83
JH
782 /* Follow "normalized" - ie "refs/.." symlinks by hand */
783 if (S_ISLNK(st.st_mode)) {
784 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
785 if (len < 0)
786 return NULL;
b54cb795 787 buffer[len] = 0;
1f58a038
MH
788 if (!prefixcmp(buffer, "refs/") &&
789 !check_refname_format(buffer, 0)) {
dfefa935
MH
790 strcpy(refname_buffer, buffer);
791 refname = refname_buffer;
8da19775
JH
792 if (flag)
793 *flag |= REF_ISSYMREF;
a876ed83
JH
794 continue;
795 }
ca8db142 796 }
a876ed83 797
7a21632f
DS
798 /* Is it a directory? */
799 if (S_ISDIR(st.st_mode)) {
800 errno = EISDIR;
801 return NULL;
802 }
803
a876ed83
JH
804 /*
805 * Anything else, just open it and try to use it as
806 * a ref
807 */
808 fd = open(path, O_RDONLY);
809 if (fd < 0)
810 return NULL;
93d26e4c 811 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 812 close(fd);
28775050
MH
813 if (len < 0)
814 return NULL;
815 while (len && isspace(buffer[len-1]))
816 len--;
817 buffer[len] = '\0';
a876ed83
JH
818
819 /*
820 * Is it a symbolic ref?
821 */
28775050 822 if (prefixcmp(buffer, "ref:"))
a876ed83 823 break;
55956350
JH
824 if (flag)
825 *flag |= REF_ISSYMREF;
a876ed83 826 buf = buffer + 4;
28775050
MH
827 while (isspace(*buf))
828 buf++;
313fb010 829 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
830 if (flag)
831 *flag |= REF_ISBROKEN;
313fb010
MH
832 return NULL;
833 }
dfefa935 834 refname = strcpy(refname_buffer, buf);
8a65ff76 835 }
f989fea0
MH
836 /* Please note that FETCH_HEAD has a second line containing other data. */
837 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
838 if (flag)
839 *flag |= REF_ISBROKEN;
a876ed83 840 return NULL;
629cd3ac 841 }
dfefa935 842 return refname;
a876ed83
JH
843}
844
96ec7b1e
NTND
845char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
846{
8cad4744 847 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
848 return ret ? xstrdup(ret) : NULL;
849}
850
d08bae7e
IL
851/* The argument to filter_refs */
852struct ref_filter {
853 const char *pattern;
854 each_ref_fn *fn;
855 void *cb_data;
856};
857
dfefa935 858int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 859{
8d68493f 860 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
861 return 0;
862 return -1;
8a65ff76
LT
863}
864
dfefa935 865int read_ref(const char *refname, unsigned char *sha1)
c6893323 866{
dfefa935 867 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
868}
869
bc5fd6d3 870int ref_exists(const char *refname)
ef06b918 871{
bc5fd6d3
MH
872 unsigned char sha1[20];
873 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
874}
875
85be1fe3 876static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 877 void *data)
d08bae7e
IL
878{
879 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 880 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 881 return 0;
85be1fe3 882 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
883}
884
dfefa935 885int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
886{
887 int flag;
888 unsigned char base[20];
889 struct object *o;
890
dfefa935
MH
891 if (current_ref && (current_ref->name == refname
892 || !strcmp(current_ref->name, refname))) {
0ae91be0 893 if (current_ref->flag & REF_KNOWS_PEELED) {
593f1bb8 894 hashcpy(sha1, current_ref->u.value.peeled);
0ae91be0
SP
895 return 0;
896 }
593f1bb8 897 hashcpy(base, current_ref->u.value.sha1);
0ae91be0
SP
898 goto fallback;
899 }
900
dfefa935 901 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
902 return -1;
903
904 if ((flag & REF_ISPACKED)) {
d3177275
MH
905 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
906 struct ref_entry *r = search_ref_dir(dir, refname);
cf0adba7 907
e9c4c111 908 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
593f1bb8 909 hashcpy(sha1, r->u.value.peeled);
e9c4c111 910 return 0;
cf0adba7 911 }
cf0adba7
JH
912 }
913
0ae91be0 914fallback:
cf0adba7 915 o = parse_object(base);
8c87dc77 916 if (o && o->type == OBJ_TAG) {
dfefa935 917 o = deref_tag(o, refname, 0);
cf0adba7
JH
918 if (o) {
919 hashcpy(sha1, o->sha1);
920 return 0;
921 }
922 }
923 return -1;
924}
925
bc5fd6d3
MH
926struct warn_if_dangling_data {
927 FILE *fp;
928 const char *refname;
929 const char *msg_fmt;
930};
931
932static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
933 int flags, void *cb_data)
934{
935 struct warn_if_dangling_data *d = cb_data;
936 const char *resolves_to;
937 unsigned char junk[20];
938
939 if (!(flags & REF_ISSYMREF))
940 return 0;
941
942 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
943 if (!resolves_to || strcmp(resolves_to, d->refname))
944 return 0;
945
946 fprintf(d->fp, d->msg_fmt, refname);
947 return 0;
948}
949
950void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
951{
952 struct warn_if_dangling_data data;
953
954 data.fp = fp;
955 data.refname = refname;
956 data.msg_fmt = msg_fmt;
957 for_each_rawref(warn_if_dangling_symref, &data);
958}
959
0bad611b
HV
960static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
961 int trim, int flags, void *cb_data)
8a65ff76 962{
316b097a 963 struct ref_cache *refs = get_ref_cache(submodule);
d3177275
MH
964 struct ref_dir *packed_refs = get_packed_refs(refs);
965 struct ref_dir *loose_refs = get_loose_refs(refs);
966 sort_ref_dir(packed_refs);
967 sort_ref_dir(loose_refs);
968 return do_for_each_ref_in_dirs(packed_refs,
969 loose_refs,
970 base, fn, trim, flags, cb_data);
8a65ff76
LT
971}
972
0bad611b 973static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
974{
975 unsigned char sha1[20];
8da19775
JH
976 int flag;
977
0bad611b
HV
978 if (submodule) {
979 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
980 return fn("HEAD", sha1, 0, cb_data);
981
982 return 0;
983 }
984
c6893323 985 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 986 return fn("HEAD", sha1, flag, cb_data);
0bad611b 987
2f34ba32 988 return 0;
723c31fe
LT
989}
990
0bad611b
HV
991int head_ref(each_ref_fn fn, void *cb_data)
992{
993 return do_head_ref(NULL, fn, cb_data);
994}
995
9ef6aeb0
HV
996int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
997{
998 return do_head_ref(submodule, fn, cb_data);
999}
1000
cb5d709f 1001int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 1002{
b3cfc406 1003 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
1004}
1005
9ef6aeb0
HV
1006int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1007{
b3cfc406 1008 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1009}
1010
2a8177b6
CC
1011int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1012{
0bad611b 1013 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1014}
1015
9ef6aeb0
HV
1016int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1017 each_ref_fn fn, void *cb_data)
1018{
1019 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1020}
1021
cb5d709f 1022int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1023{
2a8177b6 1024 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1025}
1026
9ef6aeb0
HV
1027int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1028{
1029 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1030}
1031
cb5d709f 1032int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1033{
2a8177b6 1034 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1035}
1036
9ef6aeb0
HV
1037int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1038{
1039 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1040}
1041
cb5d709f 1042int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1043{
2a8177b6 1044 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1045}
1046
9ef6aeb0
HV
1047int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1048{
1049 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1050}
1051
29268700
CC
1052int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1053{
0bad611b 1054 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1055}
1056
a1bea2c1
JT
1057int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1058{
1059 struct strbuf buf = STRBUF_INIT;
1060 int ret = 0;
1061 unsigned char sha1[20];
1062 int flag;
1063
1064 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1065 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1066 ret = fn(buf.buf, sha1, flag, cb_data);
1067 strbuf_release(&buf);
1068
1069 return ret;
1070}
1071
1072int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1073{
1074 struct strbuf buf = STRBUF_INIT;
1075 int ret;
1076 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1077 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1078 strbuf_release(&buf);
1079 return ret;
1080}
1081
b09fe971
IL
1082int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1083 const char *prefix, void *cb_data)
d08bae7e
IL
1084{
1085 struct strbuf real_pattern = STRBUF_INIT;
1086 struct ref_filter filter;
d08bae7e
IL
1087 int ret;
1088
b09fe971 1089 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1090 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1091 else if (prefix)
1092 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1093 strbuf_addstr(&real_pattern, pattern);
1094
894a9d33 1095 if (!has_glob_specials(pattern)) {
9517e6b8 1096 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1097 if (real_pattern.buf[real_pattern.len - 1] != '/')
1098 strbuf_addch(&real_pattern, '/');
1099 /* No need to check for '*', there is none. */
1100 strbuf_addch(&real_pattern, '*');
1101 }
1102
1103 filter.pattern = real_pattern.buf;
1104 filter.fn = fn;
1105 filter.cb_data = cb_data;
1106 ret = for_each_ref(filter_refs, &filter);
1107
1108 strbuf_release(&real_pattern);
1109 return ret;
1110}
1111
b09fe971
IL
1112int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1113{
1114 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1115}
1116
f8948e2f
JH
1117int for_each_rawref(each_ref_fn fn, void *cb_data)
1118{
b3cfc406 1119 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1120 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1121}
1122
4577e483 1123const char *prettify_refname(const char *name)
a9c37a72 1124{
a9c37a72
DB
1125 return name + (
1126 !prefixcmp(name, "refs/heads/") ? 11 :
1127 !prefixcmp(name, "refs/tags/") ? 10 :
1128 !prefixcmp(name, "refs/remotes/") ? 13 :
1129 0);
1130}
1131
79803322
SP
1132const char *ref_rev_parse_rules[] = {
1133 "%.*s",
1134 "refs/%.*s",
1135 "refs/tags/%.*s",
1136 "refs/heads/%.*s",
1137 "refs/remotes/%.*s",
1138 "refs/remotes/%.*s/HEAD",
1139 NULL
1140};
1141
1142int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1143{
1144 const char **p;
1145 const int abbrev_name_len = strlen(abbrev_name);
1146
1147 for (p = rules; *p; p++) {
1148 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1149 return 1;
1150 }
1151 }
1152
1153 return 0;
1154}
1155
e5f38ec3 1156static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1157 const unsigned char *old_sha1, int mustexist)
1158{
c6893323 1159 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1160 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1161 unlock_ref(lock);
1162 return NULL;
1163 }
a89fccd2 1164 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1165 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1166 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1167 unlock_ref(lock);
1168 return NULL;
1169 }
1170 return lock;
1171}
1172
7155b727 1173static int remove_empty_directories(const char *file)
bc7127ef
JH
1174{
1175 /* we want to create a file but there is a directory there;
1176 * if that is an empty directory (or a directory that contains
1177 * only empty directories), remove them.
1178 */
7155b727
JS
1179 struct strbuf path;
1180 int result;
bc7127ef 1181
7155b727
JS
1182 strbuf_init(&path, 20);
1183 strbuf_addstr(&path, file);
1184
a0f4afbe 1185 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1186
1187 strbuf_release(&path);
1188
1189 return result;
bc7127ef
JH
1190}
1191
ff74f7f1
JH
1192/*
1193 * *string and *len will only be substituted, and *string returned (for
1194 * later free()ing) if the string passed in is a magic short-hand form
1195 * to name a branch.
1196 */
1197static char *substitute_branch_name(const char **string, int *len)
1198{
1199 struct strbuf buf = STRBUF_INIT;
1200 int ret = interpret_branch_name(*string, &buf);
1201
1202 if (ret == *len) {
1203 size_t size;
1204 *string = strbuf_detach(&buf, &size);
1205 *len = size;
1206 return (char *)*string;
1207 }
1208
1209 return NULL;
1210}
1211
1212int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1213{
1214 char *last_branch = substitute_branch_name(&str, &len);
1215 const char **p, *r;
1216 int refs_found = 0;
1217
1218 *ref = NULL;
1219 for (p = ref_rev_parse_rules; *p; p++) {
1220 char fullref[PATH_MAX];
1221 unsigned char sha1_from_ref[20];
1222 unsigned char *this_result;
1223 int flag;
1224
1225 this_result = refs_found ? sha1_from_ref : sha1;
1226 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1227 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1228 if (r) {
1229 if (!refs_found++)
1230 *ref = xstrdup(r);
1231 if (!warn_ambiguous_refs)
1232 break;
55956350 1233 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1234 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1235 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1236 warning("ignoring broken ref %s.", fullref);
1237 }
ff74f7f1
JH
1238 }
1239 free(last_branch);
1240 return refs_found;
1241}
1242
1243int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1244{
1245 char *last_branch = substitute_branch_name(&str, &len);
1246 const char **p;
1247 int logs_found = 0;
1248
1249 *log = NULL;
1250 for (p = ref_rev_parse_rules; *p; p++) {
1251 struct stat st;
1252 unsigned char hash[20];
1253 char path[PATH_MAX];
1254 const char *ref, *it;
1255
1256 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1257 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1258 if (!ref)
1259 continue;
1260 if (!stat(git_path("logs/%s", path), &st) &&
1261 S_ISREG(st.st_mode))
1262 it = path;
1263 else if (strcmp(ref, path) &&
1264 !stat(git_path("logs/%s", ref), &st) &&
1265 S_ISREG(st.st_mode))
1266 it = ref;
1267 else
1268 continue;
1269 if (!logs_found++) {
1270 *log = xstrdup(it);
1271 hashcpy(sha1, hash);
1272 }
1273 if (!warn_ambiguous_refs)
1274 break;
1275 }
1276 free(last_branch);
1277 return logs_found;
1278}
1279
dfefa935
MH
1280static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1281 const unsigned char *old_sha1,
1282 int flags, int *type_p)
4bd18c43 1283{
434cd0cd 1284 char *ref_file;
dfefa935 1285 const char *orig_refname = refname;
4bd18c43 1286 struct ref_lock *lock;
5cc3cef9 1287 int last_errno = 0;
acd3b9ec 1288 int type, lflags;
4431fcc4 1289 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1290 int missing = 0;
4bd18c43
SP
1291
1292 lock = xcalloc(1, sizeof(struct ref_lock));
1293 lock->lock_fd = -1;
1294
8d68493f 1295 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1296 if (!refname && errno == EISDIR) {
bc7127ef
JH
1297 /* we are trying to lock foo but we used to
1298 * have foo/bar which now does not exist;
1299 * it is normal for the empty directory 'foo'
1300 * to remain.
1301 */
dfefa935 1302 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1303 if (remove_empty_directories(ref_file)) {
1304 last_errno = errno;
dfefa935 1305 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1306 goto error_return;
1307 }
8d68493f 1308 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1309 }
68db31cc
SV
1310 if (type_p)
1311 *type_p = type;
dfefa935 1312 if (!refname) {
5cc3cef9 1313 last_errno = errno;
818f477c 1314 error("unable to resolve reference %s: %s",
dfefa935 1315 orig_refname, strerror(errno));
5cc3cef9 1316 goto error_return;
4bd18c43 1317 }
5bdd8d4a 1318 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1319 /* When the ref did not exist and we are creating it,
1320 * make sure there is no existing ref that is packed
1321 * whose name begins with our refname, nor a ref whose
1322 * name is a proper prefix of our refname.
1323 */
5bdd8d4a 1324 if (missing &&
316b097a 1325 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1326 last_errno = ENOTDIR;
c976d415 1327 goto error_return;
f475e08e 1328 }
22a3844e 1329
c33d5174 1330 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1331
acd3b9ec
JH
1332 lflags = LOCK_DIE_ON_ERROR;
1333 if (flags & REF_NODEREF) {
dfefa935 1334 refname = orig_refname;
acd3b9ec
JH
1335 lflags |= LOCK_NODEREF;
1336 }
dfefa935
MH
1337 lock->ref_name = xstrdup(refname);
1338 lock->orig_ref_name = xstrdup(orig_refname);
1339 ref_file = git_path("%s", refname);
5bdd8d4a 1340 if (missing)
68db31cc
SV
1341 lock->force_write = 1;
1342 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1343 lock->force_write = 1;
4bd18c43 1344
5cc3cef9
JH
1345 if (safe_create_leading_directories(ref_file)) {
1346 last_errno = errno;
1347 error("unable to create directory for %s", ref_file);
1348 goto error_return;
1349 }
4bd18c43 1350
acd3b9ec 1351 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1352 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1353
1354 error_return:
1355 unlock_ref(lock);
1356 errno = last_errno;
1357 return NULL;
4bd18c43
SP
1358}
1359
dfefa935 1360struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1361{
53cce84c 1362 char refpath[PATH_MAX];
dfefa935 1363 if (check_refname_format(refname, 0))
4bd18c43 1364 return NULL;
dfefa935 1365 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1366 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1367}
1368
dfefa935
MH
1369struct ref_lock *lock_any_ref_for_update(const char *refname,
1370 const unsigned char *old_sha1, int flags)
4bd18c43 1371{
dfefa935 1372 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1373 return NULL;
dfefa935 1374 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1375}
1376
d66da478
MH
1377struct repack_without_ref_sb {
1378 const char *refname;
1379 int fd;
1380};
1381
1382static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1383 int flags, void *cb_data)
1384{
1385 struct repack_without_ref_sb *data = cb_data;
1386 char line[PATH_MAX + 100];
1387 int len;
1388
1389 if (!strcmp(data->refname, refname))
1390 return 0;
1391 len = snprintf(line, sizeof(line), "%s %s\n",
1392 sha1_to_hex(sha1), refname);
1393 /* this should not happen but just being defensive */
1394 if (len > sizeof(line))
1395 die("too long a refname '%s'", refname);
1396 write_or_die(data->fd, line, len);
1397 return 0;
1398}
1399
26a063a1
JH
1400static struct lock_file packlock;
1401
c0277d15
JH
1402static int repack_without_ref(const char *refname)
1403{
d66da478 1404 struct repack_without_ref_sb data;
d3177275
MH
1405 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
1406 sort_ref_dir(packed);
1407 if (search_ref_dir(packed, refname) == NULL)
c0277d15 1408 return 0;
d66da478
MH
1409 data.refname = refname;
1410 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1411 if (data.fd < 0) {
1b018fd9 1412 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1413 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1414 }
d3177275 1415 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1416 return commit_lock_file(&packlock);
1417}
1418
eca35a25 1419int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1420{
1421 struct ref_lock *lock;
eca35a25 1422 int err, i = 0, ret = 0, flag = 0;
c0277d15 1423
68db31cc 1424 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1425 if (!lock)
1426 return 1;
045a476f 1427 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1428 /* loose */
eca35a25
MV
1429 const char *path;
1430
1431 if (!(delopt & REF_NODEREF)) {
1432 i = strlen(lock->lk->filename) - 5; /* .lock */
1433 lock->lk->filename[i] = 0;
1434 path = lock->lk->filename;
1435 } else {
9db56f71 1436 path = git_path("%s", refname);
eca35a25 1437 }
691f1a28
AR
1438 err = unlink_or_warn(path);
1439 if (err && errno != ENOENT)
c0277d15 1440 ret = 1;
691f1a28 1441
eca35a25
MV
1442 if (!(delopt & REF_NODEREF))
1443 lock->lk->filename[i] = '.';
c0277d15
JH
1444 }
1445 /* removing the loose one could have resurrected an earlier
1446 * packed one. Also, if it was not loose we need to repack
1447 * without it.
1448 */
1449 ret |= repack_without_ref(refname);
1450
691f1a28 1451 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1452 invalidate_ref_cache(NULL);
c0277d15
JH
1453 unlock_ref(lock);
1454 return ret;
4bd18c43
SP
1455}
1456
765c2258
PH
1457/*
1458 * People using contrib's git-new-workdir have .git/logs/refs ->
1459 * /some/other/path/.git/logs/refs, and that may live on another device.
1460 *
1461 * IOW, to avoid cross device rename errors, the temporary renamed log must
1462 * live into logs/refs.
1463 */
1464#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1465
dfefa935 1466int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1467{
c976d415
LH
1468 unsigned char sha1[20], orig_sha1[20];
1469 int flag = 0, logmoved = 0;
1470 struct ref_lock *lock;
c976d415 1471 struct stat loginfo;
dfefa935 1472 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1473 const char *symref = NULL;
316b097a 1474 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1475
450d4c0f 1476 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1477 return error("reflog for %s is a symlink", oldrefname);
c976d415 1478
8d68493f 1479 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1480 if (flag & REF_ISSYMREF)
fa58186c 1481 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1482 oldrefname);
eca35a25 1483 if (!symref)
dfefa935 1484 return error("refname %s not found", oldrefname);
c976d415 1485
316b097a 1486 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1487 return 1;
1488
316b097a 1489 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1490 return 1;
1491
dfefa935 1492 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1493 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1494 oldrefname, strerror(errno));
c976d415 1495
dfefa935
MH
1496 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1497 error("unable to delete old %s", oldrefname);
c976d415
LH
1498 goto rollback;
1499 }
1500
dfefa935
MH
1501 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1502 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1503 if (errno==EISDIR) {
dfefa935
MH
1504 if (remove_empty_directories(git_path("%s", newrefname))) {
1505 error("Directory not empty: %s", newrefname);
c976d415
LH
1506 goto rollback;
1507 }
1508 } else {
dfefa935 1509 error("unable to delete existing %s", newrefname);
c976d415
LH
1510 goto rollback;
1511 }
1512 }
1513
dfefa935
MH
1514 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1515 error("unable to create directory for %s", newrefname);
c976d415
LH
1516 goto rollback;
1517 }
1518
1519 retry:
dfefa935 1520 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1521 if (errno==EISDIR || errno==ENOTDIR) {
1522 /*
1523 * rename(a, b) when b is an existing
1524 * directory ought to result in ISDIR, but
1525 * Solaris 5.8 gives ENOTDIR. Sheesh.
1526 */
dfefa935
MH
1527 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1528 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1529 goto rollback;
1530 }
1531 goto retry;
1532 } else {
765c2258 1533 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1534 newrefname, strerror(errno));
c976d415
LH
1535 goto rollback;
1536 }
1537 }
1538 logmoved = log;
1539
dfefa935 1540 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1541 if (!lock) {
dfefa935 1542 error("unable to lock %s for update", newrefname);
c976d415
LH
1543 goto rollback;
1544 }
c976d415
LH
1545 lock->force_write = 1;
1546 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1547 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1548 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1549 goto rollback;
1550 }
1551
1552 return 0;
1553
1554 rollback:
dfefa935 1555 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1556 if (!lock) {
dfefa935 1557 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1558 goto rollbacklog;
1559 }
1560
1561 lock->force_write = 1;
1562 flag = log_all_ref_updates;
1563 log_all_ref_updates = 0;
1564 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1565 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1566 log_all_ref_updates = flag;
1567
1568 rollbacklog:
dfefa935 1569 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1570 error("unable to restore logfile %s from %s: %s",
dfefa935 1571 oldrefname, newrefname, strerror(errno));
c976d415 1572 if (!logmoved && log &&
dfefa935 1573 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1574 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1575 oldrefname, strerror(errno));
c976d415
LH
1576
1577 return 1;
1578}
1579
435fc852 1580int close_ref(struct ref_lock *lock)
b531394d
BC
1581{
1582 if (close_lock_file(lock->lk))
1583 return -1;
1584 lock->lock_fd = -1;
1585 return 0;
1586}
1587
435fc852 1588int commit_ref(struct ref_lock *lock)
b531394d
BC
1589{
1590 if (commit_lock_file(lock->lk))
1591 return -1;
1592 lock->lock_fd = -1;
1593 return 0;
1594}
1595
e5f38ec3 1596void unlock_ref(struct ref_lock *lock)
4bd18c43 1597{
4ed7cd3a
BC
1598 /* Do not free lock->lk -- atexit() still looks at them */
1599 if (lock->lk)
1600 rollback_lock_file(lock->lk);
434cd0cd 1601 free(lock->ref_name);
1655707c 1602 free(lock->orig_ref_name);
4bd18c43
SP
1603 free(lock);
1604}
1605
0ec29a47
JH
1606/*
1607 * copy the reflog message msg to buf, which has been allocated sufficiently
1608 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1609 * because reflog file is one line per entry.
1610 */
1611static int copy_msg(char *buf, const char *msg)
1612{
1613 char *cp = buf;
1614 char c;
1615 int wasspace = 1;
1616
1617 *cp++ = '\t';
1618 while ((c = *msg++)) {
1619 if (wasspace && isspace(c))
1620 continue;
1621 wasspace = isspace(c);
1622 if (wasspace)
1623 c = ' ';
1624 *cp++ = c;
1625 }
1626 while (buf < cp && isspace(cp[-1]))
1627 cp--;
1628 *cp++ = '\n';
1629 return cp - buf;
1630}
1631
dfefa935 1632int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 1633{
859c3017 1634 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1635
dfefa935 1636 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 1637 if (log_all_ref_updates &&
dfefa935
MH
1638 (!prefixcmp(refname, "refs/heads/") ||
1639 !prefixcmp(refname, "refs/remotes/") ||
1640 !prefixcmp(refname, "refs/notes/") ||
1641 !strcmp(refname, "HEAD"))) {
157aaea5 1642 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1643 return error("unable to create directory for %s",
157aaea5 1644 logfile);
6de08ae6
SP
1645 oflags |= O_CREAT;
1646 }
1647
157aaea5 1648 logfd = open(logfile, oflags, 0666);
6de08ae6 1649 if (logfd < 0) {
1974bf62 1650 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1651 return 0;
3b463c3f
JH
1652
1653 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1654 if (remove_empty_directories(logfile)) {
3b463c3f 1655 return error("There are still logs under '%s'",
157aaea5 1656 logfile);
3b463c3f 1657 }
157aaea5 1658 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1659 }
1660
1661 if (logfd < 0)
1662 return error("Unable to append to %s: %s",
157aaea5 1663 logfile, strerror(errno));
6de08ae6
SP
1664 }
1665
157aaea5 1666 adjust_shared_perm(logfile);
859c3017
EM
1667 close(logfd);
1668 return 0;
1669}
443b92b6 1670
dfefa935 1671static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
1672 const unsigned char *new_sha1, const char *msg)
1673{
1674 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1675 unsigned maxlen, len;
1676 int msglen;
157aaea5 1677 char log_file[PATH_MAX];
859c3017
EM
1678 char *logrec;
1679 const char *committer;
1680
1681 if (log_all_ref_updates < 0)
1682 log_all_ref_updates = !is_bare_repository();
1683
dfefa935 1684 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
1685 if (result)
1686 return result;
1687
1688 logfd = open(log_file, oflags);
1689 if (logfd < 0)
1690 return 0;
0ec29a47 1691 msglen = msg ? strlen(msg) : 0;
774751a8 1692 committer = git_committer_info(0);
8ac65937
JH
1693 maxlen = strlen(committer) + msglen + 100;
1694 logrec = xmalloc(maxlen);
1695 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1696 sha1_to_hex(old_sha1),
1697 sha1_to_hex(new_sha1),
8ac65937
JH
1698 committer);
1699 if (msglen)
0ec29a47 1700 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1701 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1702 free(logrec);
91c8d590 1703 if (close(logfd) != 0 || written != len)
9a13f0b7 1704 return error("Unable to append to %s", log_file);
6de08ae6
SP
1705 return 0;
1706}
1707
c3b0dec5
LT
1708static int is_branch(const char *refname)
1709{
1710 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1711}
1712
4bd18c43
SP
1713int write_ref_sha1(struct ref_lock *lock,
1714 const unsigned char *sha1, const char *logmsg)
1715{
1716 static char term = '\n';
c3b0dec5 1717 struct object *o;
4bd18c43
SP
1718
1719 if (!lock)
95fc7512 1720 return -1;
a89fccd2 1721 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1722 unlock_ref(lock);
1723 return 0;
95fc7512 1724 }
c3b0dec5
LT
1725 o = parse_object(sha1);
1726 if (!o) {
7be8b3ba 1727 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
1728 lock->ref_name, sha1_to_hex(sha1));
1729 unlock_ref(lock);
1730 return -1;
1731 }
1732 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1733 error("Trying to write non-commit object %s to branch %s",
1734 sha1_to_hex(sha1), lock->ref_name);
1735 unlock_ref(lock);
1736 return -1;
1737 }
93822c22
AW
1738 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1739 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1740 || close_ref(lock) < 0) {
c33d5174 1741 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1742 unlock_ref(lock);
1743 return -1;
1744 }
8bf90dc9 1745 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
1746 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1747 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1748 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1749 unlock_ref(lock);
1750 return -1;
1751 }
605fac8b
NP
1752 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1753 /*
1754 * Special hack: If a branch is updated directly and HEAD
1755 * points to it (may happen on the remote side of a push
1756 * for example) then logically the HEAD reflog should be
1757 * updated too.
1758 * A generic solution implies reverse symref information,
1759 * but finding all symrefs pointing to the given branch
1760 * would be rather costly for this rare event (the direct
1761 * update of a branch) to be worth it. So let's cheat and
1762 * check with HEAD only which should cover 99% of all usage
1763 * scenarios (even 100% of the default ones).
1764 */
1765 unsigned char head_sha1[20];
1766 int head_flag;
1767 const char *head_ref;
8cad4744 1768 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
1769 if (head_ref && (head_flag & REF_ISSYMREF) &&
1770 !strcmp(head_ref, lock->ref_name))
1771 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1772 }
b531394d 1773 if (commit_ref(lock)) {
434cd0cd 1774 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1775 unlock_ref(lock);
1776 return -1;
1777 }
4bd18c43
SP
1778 unlock_ref(lock);
1779 return 0;
95fc7512 1780}
d556fae2 1781
8b5157e4
NP
1782int create_symref(const char *ref_target, const char *refs_heads_master,
1783 const char *logmsg)
41b625b0
NP
1784{
1785 const char *lockpath;
1786 char ref[1000];
1787 int fd, len, written;
a4f34cbb 1788 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1789 unsigned char old_sha1[20], new_sha1[20];
1790
1791 if (logmsg && read_ref(ref_target, old_sha1))
1792 hashclr(old_sha1);
41b625b0 1793
d48744d1
JH
1794 if (safe_create_leading_directories(git_HEAD) < 0)
1795 return error("unable to create directory for %s", git_HEAD);
1796
41b625b0
NP
1797#ifndef NO_SYMLINK_HEAD
1798 if (prefer_symlink_refs) {
1799 unlink(git_HEAD);
1800 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1801 goto done;
41b625b0
NP
1802 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1803 }
1804#endif
1805
1806 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1807 if (sizeof(ref) <= len) {
1808 error("refname too long: %s", refs_heads_master);
47fc52e2 1809 goto error_free_return;
41b625b0
NP
1810 }
1811 lockpath = mkpath("%s.lock", git_HEAD);
1812 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1813 if (fd < 0) {
1814 error("Unable to open %s for writing", lockpath);
47fc52e2 1815 goto error_free_return;
41b625b0
NP
1816 }
1817 written = write_in_full(fd, ref, len);
91c8d590 1818 if (close(fd) != 0 || written != len) {
41b625b0 1819 error("Unable to write to %s", lockpath);
47fc52e2 1820 goto error_unlink_return;
41b625b0
NP
1821 }
1822 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1823 error("Unable to create %s", git_HEAD);
47fc52e2 1824 goto error_unlink_return;
41b625b0
NP
1825 }
1826 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1827 error("Unable to fix permissions on %s", lockpath);
47fc52e2 1828 error_unlink_return:
691f1a28 1829 unlink_or_warn(lockpath);
47fc52e2
JH
1830 error_free_return:
1831 free(git_HEAD);
1832 return -1;
41b625b0 1833 }
8b5157e4 1834
ee96d11b 1835#ifndef NO_SYMLINK_HEAD
8b5157e4 1836 done:
ee96d11b 1837#endif
8b5157e4
NP
1838 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1839 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1840
47fc52e2 1841 free(git_HEAD);
41b625b0
NP
1842 return 0;
1843}
1844
16d7cc90
JH
1845static char *ref_msg(const char *line, const char *endp)
1846{
1847 const char *ep;
16d7cc90 1848 line += 82;
182af834
PH
1849 ep = memchr(line, '\n', endp - line);
1850 if (!ep)
1851 ep = endp;
1852 return xmemdupz(line, ep - line);
16d7cc90
JH
1853}
1854
dfefa935
MH
1855int read_ref_at(const char *refname, unsigned long at_time, int cnt,
1856 unsigned char *sha1, char **msg,
1857 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 1858{
e5229042 1859 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1860 char *tz_c;
e29cb53a 1861 int logfd, tz, reccnt = 0;
d556fae2
SP
1862 struct stat st;
1863 unsigned long date;
e5229042 1864 unsigned char logged_sha1[20];
cb48cb58 1865 void *log_mapped;
dc49cd76 1866 size_t mapsz;
d556fae2 1867
dfefa935 1868 logfile = git_path("logs/%s", refname);
d556fae2
SP
1869 logfd = open(logfile, O_RDONLY, 0);
1870 if (logfd < 0)
d824cbba 1871 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
1872 fstat(logfd, &st);
1873 if (!st.st_size)
1874 die("Log %s is empty.", logfile);
dc49cd76
SP
1875 mapsz = xsize_t(st.st_size);
1876 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1877 logdata = log_mapped;
d556fae2
SP
1878 close(logfd);
1879
e5229042 1880 lastrec = NULL;
d556fae2
SP
1881 rec = logend = logdata + st.st_size;
1882 while (logdata < rec) {
e29cb53a 1883 reccnt++;
d556fae2
SP
1884 if (logdata < rec && *(rec-1) == '\n')
1885 rec--;
e5229042
SP
1886 lastgt = NULL;
1887 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1888 rec--;
e5229042
SP
1889 if (*rec == '>')
1890 lastgt = rec;
1891 }
1892 if (!lastgt)
d556fae2 1893 die("Log %s is corrupt.", logfile);
e5229042 1894 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1895 if (date <= at_time || cnt == 0) {
76a44c5c 1896 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1897 if (msg)
1898 *msg = ref_msg(rec, logend);
1899 if (cutoff_time)
1900 *cutoff_time = date;
1901 if (cutoff_tz)
1902 *cutoff_tz = tz;
1903 if (cutoff_cnt)
76a44c5c 1904 *cutoff_cnt = reccnt - 1;
e5229042
SP
1905 if (lastrec) {
1906 if (get_sha1_hex(lastrec, logged_sha1))
1907 die("Log %s is corrupt.", logfile);
1908 if (get_sha1_hex(rec + 41, sha1))
1909 die("Log %s is corrupt.", logfile);
a89fccd2 1910 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1911 warning("Log %s has gap after %s.",
73013afd 1912 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1913 }
e5f38ec3
JH
1914 }
1915 else if (date == at_time) {
e5229042
SP
1916 if (get_sha1_hex(rec + 41, sha1))
1917 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1918 }
1919 else {
e5229042
SP
1920 if (get_sha1_hex(rec + 41, logged_sha1))
1921 die("Log %s is corrupt.", logfile);
a89fccd2 1922 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1923 warning("Log %s unexpectedly ended on %s.",
73013afd 1924 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1925 }
1926 }
dc49cd76 1927 munmap(log_mapped, mapsz);
d556fae2
SP
1928 return 0;
1929 }
e5229042 1930 lastrec = rec;
ab2a1a32
JH
1931 if (cnt > 0)
1932 cnt--;
d556fae2
SP
1933 }
1934
e5229042
SP
1935 rec = logdata;
1936 while (rec < logend && *rec != '>' && *rec != '\n')
1937 rec++;
1938 if (rec == logend || *rec == '\n')
d556fae2 1939 die("Log %s is corrupt.", logfile);
e5229042 1940 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1941 tz = strtoul(tz_c, NULL, 10);
1942 if (get_sha1_hex(logdata, sha1))
1943 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1944 if (is_null_sha1(sha1)) {
1945 if (get_sha1_hex(logdata + 41, sha1))
1946 die("Log %s is corrupt.", logfile);
1947 }
16d7cc90
JH
1948 if (msg)
1949 *msg = ref_msg(logdata, logend);
dc49cd76 1950 munmap(log_mapped, mapsz);
16d7cc90
JH
1951
1952 if (cutoff_time)
1953 *cutoff_time = date;
1954 if (cutoff_tz)
1955 *cutoff_tz = tz;
1956 if (cutoff_cnt)
1957 *cutoff_cnt = reccnt;
1958 return 1;
d556fae2 1959}
2ff81662 1960
dfefa935 1961int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
1962{
1963 const char *logfile;
1964 FILE *logfp;
8ca78803 1965 struct strbuf sb = STRBUF_INIT;
2266bf27 1966 int ret = 0;
2ff81662 1967
dfefa935 1968 logfile = git_path("logs/%s", refname);
2ff81662
JH
1969 logfp = fopen(logfile, "r");
1970 if (!logfp)
883d60fa 1971 return -1;
101d15e0
JH
1972
1973 if (ofs) {
1974 struct stat statbuf;
1975 if (fstat(fileno(logfp), &statbuf) ||
1976 statbuf.st_size < ofs ||
1977 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 1978 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 1979 fclose(logfp);
8ca78803 1980 strbuf_release(&sb);
101d15e0 1981 return -1;
9d33f7c2 1982 }
101d15e0
JH
1983 }
1984
8ca78803 1985 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 1986 unsigned char osha1[20], nsha1[20];
883d60fa
JS
1987 char *email_end, *message;
1988 unsigned long timestamp;
8ca78803 1989 int tz;
2ff81662
JH
1990
1991 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
1992 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1993 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1994 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1995 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
1996 email_end[1] != ' ' ||
1997 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1998 !message || message[0] != ' ' ||
1999 (message[1] != '+' && message[1] != '-') ||
2000 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 2001 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 2002 continue; /* corrupt? */
883d60fa
JS
2003 email_end[1] = '\0';
2004 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2005 if (message[6] != '\t')
2006 message += 6;
2007 else
2008 message += 7;
8ca78803
RS
2009 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2010 cb_data);
883d60fa 2011 if (ret)
2266bf27 2012 break;
2ff81662
JH
2013 }
2014 fclose(logfp);
8ca78803 2015 strbuf_release(&sb);
2266bf27 2016 return ret;
2ff81662 2017}
e29cb53a 2018
dfefa935 2019int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2020{
dfefa935 2021 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2022}
2023
eb8381c8
NP
2024static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
2025{
d3177275 2026 DIR *d = opendir(git_path("logs/%s", base));
fcee5a14 2027 int retval = 0;
eb8381c8 2028
d3177275 2029 if (d) {
eb8381c8
NP
2030 struct dirent *de;
2031 int baselen = strlen(base);
2032 char *log = xmalloc(baselen + 257);
2033
2034 memcpy(log, base, baselen);
2035 if (baselen && base[baselen-1] != '/')
2036 log[baselen++] = '/';
2037
d3177275 2038 while ((de = readdir(d)) != NULL) {
eb8381c8
NP
2039 struct stat st;
2040 int namelen;
2041
2042 if (de->d_name[0] == '.')
2043 continue;
2044 namelen = strlen(de->d_name);
2045 if (namelen > 255)
2046 continue;
2047 if (has_extension(de->d_name, ".lock"))
2048 continue;
2049 memcpy(log + baselen, de->d_name, namelen+1);
2050 if (stat(git_path("logs/%s", log), &st) < 0)
2051 continue;
2052 if (S_ISDIR(st.st_mode)) {
2053 retval = do_for_each_reflog(log, fn, cb_data);
2054 } else {
2055 unsigned char sha1[20];
c6893323 2056 if (read_ref_full(log, sha1, 0, NULL))
eb8381c8
NP
2057 retval = error("bad ref for %s", log);
2058 else
2059 retval = fn(log, sha1, 0, cb_data);
2060 }
2061 if (retval)
2062 break;
2063 }
2064 free(log);
d3177275 2065 closedir(d);
eb8381c8 2066 }
acb39f64 2067 else if (*base)
fcee5a14 2068 return errno;
eb8381c8
NP
2069 return retval;
2070}
2071
2072int for_each_reflog(each_ref_fn fn, void *cb_data)
2073{
2074 return do_for_each_reflog("", fn, cb_data);
2075}
3d9f037c
CR
2076
2077int update_ref(const char *action, const char *refname,
2078 const unsigned char *sha1, const unsigned char *oldval,
2079 int flags, enum action_on_err onerr)
2080{
2081 static struct ref_lock *lock;
2082 lock = lock_any_ref_for_update(refname, oldval, flags);
2083 if (!lock) {
2084 const char *str = "Cannot lock the ref '%s'.";
2085 switch (onerr) {
2086 case MSG_ON_ERR: error(str, refname); break;
2087 case DIE_ON_ERR: die(str, refname); break;
2088 case QUIET_ON_ERR: break;
2089 }
2090 return 1;
2091 }
2092 if (write_ref_sha1(lock, sha1, action) < 0) {
2093 const char *str = "Cannot update the ref '%s'.";
2094 switch (onerr) {
2095 case MSG_ON_ERR: error(str, refname); break;
2096 case DIE_ON_ERR: die(str, refname); break;
2097 case QUIET_ON_ERR: break;
2098 }
2099 return 1;
2100 }
2101 return 0;
2102}
cda69f48 2103
5483f799 2104struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2105{
2106 for ( ; list; list = list->next)
2107 if (!strcmp(list->name, name))
5483f799 2108 return (struct ref *)list;
cda69f48
JK
2109 return NULL;
2110}
7c2b3029
JK
2111
2112/*
2113 * generate a format suitable for scanf from a ref_rev_parse_rules
2114 * rule, that is replace the "%.*s" spec with a "%s" spec
2115 */
2116static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2117{
2118 char *spec;
2119
2120 spec = strstr(rule, "%.*s");
2121 if (!spec || strstr(spec + 4, "%.*s"))
2122 die("invalid rule in ref_rev_parse_rules: %s", rule);
2123
2124 /* copy all until spec */
2125 strncpy(scanf_fmt, rule, spec - rule);
2126 scanf_fmt[spec - rule] = '\0';
2127 /* copy new spec */
2128 strcat(scanf_fmt, "%s");
2129 /* copy remaining rule */
2130 strcat(scanf_fmt, spec + 4);
2131
2132 return;
2133}
2134
dfefa935 2135char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2136{
2137 int i;
2138 static char **scanf_fmts;
2139 static int nr_rules;
2140 char *short_name;
2141
2142 /* pre generate scanf formats from ref_rev_parse_rules[] */
2143 if (!nr_rules) {
2144 size_t total_len = 0;
2145
2146 /* the rule list is NULL terminated, count them first */
2147 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2148 /* no +1 because strlen("%s") < strlen("%.*s") */
2149 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2150
2151 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2152
2153 total_len = 0;
2154 for (i = 0; i < nr_rules; i++) {
2155 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2156 + total_len;
2157 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2158 total_len += strlen(ref_rev_parse_rules[i]);
2159 }
2160 }
2161
2162 /* bail out if there are no rules */
2163 if (!nr_rules)
dfefa935 2164 return xstrdup(refname);
7c2b3029 2165
dfefa935
MH
2166 /* buffer for scanf result, at most refname must fit */
2167 short_name = xstrdup(refname);
7c2b3029
JK
2168
2169 /* skip first rule, it will always match */
2170 for (i = nr_rules - 1; i > 0 ; --i) {
2171 int j;
6e7b3309 2172 int rules_to_fail = i;
7c2b3029
JK
2173 int short_name_len;
2174
dfefa935 2175 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2176 continue;
2177
2178 short_name_len = strlen(short_name);
2179
6e7b3309
BW
2180 /*
2181 * in strict mode, all (except the matched one) rules
2182 * must fail to resolve to a valid non-ambiguous ref
2183 */
2184 if (strict)
2185 rules_to_fail = nr_rules;
2186
7c2b3029
JK
2187 /*
2188 * check if the short name resolves to a valid ref,
2189 * but use only rules prior to the matched one
2190 */
6e7b3309 2191 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2192 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2193 char refname[PATH_MAX];
2194
6e7b3309
BW
2195 /* skip matched rule */
2196 if (i == j)
2197 continue;
2198
7c2b3029
JK
2199 /*
2200 * the short name is ambiguous, if it resolves
2201 * (with this previous rule) to a valid ref
2202 * read_ref() returns 0 on success
2203 */
2204 mksnpath(refname, sizeof(refname),
2205 rule, short_name_len, short_name);
c6893323 2206 if (ref_exists(refname))
7c2b3029
JK
2207 break;
2208 }
2209
2210 /*
2211 * short name is non-ambiguous if all previous rules
2212 * haven't resolved to a valid ref
2213 */
6e7b3309 2214 if (j == rules_to_fail)
7c2b3029
JK
2215 return short_name;
2216 }
2217
2218 free(short_name);
dfefa935 2219 return xstrdup(refname);
7c2b3029 2220}