free_ref_entry(): new function
[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)
54 return -1; /* Component has zero length. */
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);
77 if (component_len < 0) {
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
e9c4c111
JP
104struct ref_array {
105 int nr, alloc;
e6ed3ca6
MH
106
107 /*
108 * Entries with index 0 <= i < sorted are sorted by name. New
109 * entries are appended to the list unsorted, and are sorted
110 * only when required; thus we avoid the need to sort the list
111 * after the addition of every reference.
112 */
113 int sorted;
114
e9c4c111
JP
115 struct ref_entry **refs;
116};
117
bc5fd6d3
MH
118/* ISSYMREF=0x01, ISPACKED=0x02 and ISBROKEN=0x04 are public interfaces */
119#define REF_KNOWS_PEELED 0x10
cf0adba7 120
bc5fd6d3
MH
121struct ref_entry {
122 unsigned char flag; /* ISSYMREF? ISPACKED? */
123 unsigned char sha1[20];
124 unsigned char peeled[20];
125 /* The full name of the reference (e.g., "refs/heads/master"): */
126 char name[FLEX_ARRAY];
127};
e1e22e37 128
cddc4258
MH
129static struct ref_entry *create_ref_entry(const char *refname,
130 const unsigned char *sha1, int flag,
131 int check_name)
e1e22e37
LT
132{
133 int len;
cddc4258 134 struct ref_entry *ref;
e1e22e37 135
09116a1c 136 if (check_name &&
dfefa935
MH
137 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
138 die("Reference has invalid format: '%s'", refname);
cddc4258
MH
139 len = strlen(refname) + 1;
140 ref = xmalloc(sizeof(struct ref_entry) + len);
141 hashcpy(ref->sha1, sha1);
142 hashclr(ref->peeled);
143 memcpy(ref->name, refname, len);
144 ref->flag = flag;
145 return ref;
146}
147
732134ed
MH
148static void free_ref_entry(struct ref_entry *entry)
149{
150 free(entry);
151}
152
cddc4258 153/* Add a ref_entry to the end of the ref_array (unsorted). */
dd73ecd1 154static void add_ref(struct ref_array *refs, struct ref_entry *ref)
cddc4258 155{
e9c4c111 156 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
cddc4258 157 refs->refs[refs->nr++] = ref;
c774aab9
JP
158}
159
bc5fd6d3
MH
160static void clear_ref_array(struct ref_array *array)
161{
162 int i;
163 for (i = 0; i < array->nr; i++)
732134ed 164 free_ref_entry(array->refs[i]);
bc5fd6d3
MH
165 free(array->refs);
166 array->sorted = array->nr = array->alloc = 0;
167 array->refs = NULL;
168}
169
e9c4c111 170static int ref_entry_cmp(const void *a, const void *b)
c774aab9 171{
e9c4c111
JP
172 struct ref_entry *one = *(struct ref_entry **)a;
173 struct ref_entry *two = *(struct ref_entry **)b;
174 return strcmp(one->name, two->name);
175}
c774aab9 176
bc5fd6d3
MH
177static void sort_ref_array(struct ref_array *array);
178
179static struct ref_entry *search_ref_array(struct ref_array *array, const char *refname)
180{
181 struct ref_entry *e, **r;
182 int len;
183
184 if (refname == NULL)
185 return NULL;
186
187 if (!array->nr)
188 return NULL;
189 sort_ref_array(array);
190 len = strlen(refname) + 1;
191 e = xmalloc(sizeof(struct ref_entry) + len);
192 memcpy(e->name, refname, len);
193
194 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
195
196 free(e);
197
198 if (r == NULL)
199 return NULL;
200
201 return *r;
202}
203
202a56a9
MH
204/*
205 * Emit a warning and return true iff ref1 and ref2 have the same name
206 * and the same sha1. Die if they have the same name but different
207 * sha1s.
208 */
209static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
210{
211 if (!strcmp(ref1->name, ref2->name)) {
212 /* Duplicate name; make sure that the SHA1s match: */
213 if (hashcmp(ref1->sha1, ref2->sha1))
214 die("Duplicated ref, and SHA1s don't match: %s",
215 ref1->name);
216 warning("Duplicated ref: %s", ref1->name);
217 return 1;
218 } else {
219 return 0;
220 }
221}
222
e6ed3ca6
MH
223/*
224 * Sort the entries in array (if they are not already sorted).
225 */
e9c4c111
JP
226static void sort_ref_array(struct ref_array *array)
227{
202a56a9 228 int i, j;
c774aab9 229
e6ed3ca6
MH
230 /*
231 * This check also prevents passing a zero-length array to qsort(),
232 * which is a problem on some platforms.
233 */
234 if (array->sorted == array->nr)
e9c4c111 235 return;
c774aab9 236
e9c4c111 237 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
c774aab9 238
e9c4c111 239 /* Remove any duplicates from the ref_array */
202a56a9
MH
240 i = 0;
241 for (j = 1; j < array->nr; j++) {
242 if (is_dup_ref(array->refs[i], array->refs[j])) {
732134ed 243 free_ref_entry(array->refs[j]);
e9c4c111
JP
244 continue;
245 }
202a56a9 246 array->refs[++i] = array->refs[j];
e9c4c111 247 }
e6ed3ca6 248 array->sorted = array->nr = i + 1;
e9c4c111 249}
c774aab9 250
bc5fd6d3 251#define DO_FOR_EACH_INCLUDE_BROKEN 01
c774aab9 252
bc5fd6d3 253static struct ref_entry *current_ref;
c774aab9 254
bc5fd6d3
MH
255static int do_one_ref(const char *base, each_ref_fn fn, int trim,
256 int flags, void *cb_data, struct ref_entry *entry)
257{
429213e4 258 int retval;
bc5fd6d3
MH
259 if (prefixcmp(entry->name, base))
260 return 0;
c774aab9 261
bc5fd6d3
MH
262 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
263 if (entry->flag & REF_ISBROKEN)
264 return 0; /* ignore broken refs e.g. dangling symref */
265 if (!has_sha1_file(entry->sha1)) {
266 error("%s does not point to a valid object!", entry->name);
267 return 0;
268 }
269 }
270 current_ref = entry;
429213e4
MH
271 retval = fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
272 current_ref = NULL;
273 return retval;
bc5fd6d3 274}
c774aab9 275
c36b5bc2
MH
276/*
277 * Call fn for each reference in array that has index in the range
278 * offset <= index < array->nr. This function does not sort the
279 * array; sorting should be done by the caller.
280 */
281static int do_for_each_ref_in_array(struct ref_array *array, int offset,
282 const char *base,
283 each_ref_fn fn, int trim, int flags, void *cb_data)
284{
285 int i;
286 assert(array->sorted == array->nr);
287 for (i = offset; i < array->nr; i++) {
288 int retval = do_one_ref(base, fn, trim, flags, cb_data, array->refs[i]);
289 if (retval)
290 return retval;
291 }
292 return 0;
293}
294
b3fd060f
MH
295/*
296 * Call fn for each reference in the union of array1 and array2, in
297 * order by refname. If an entry appears in both array1 and array2,
298 * then only process the version that is in array2. The input arrays
299 * must already be sorted.
300 */
301static int do_for_each_ref_in_arrays(struct ref_array *array1,
302 struct ref_array *array2,
303 const char *base, each_ref_fn fn, int trim,
304 int flags, void *cb_data)
305{
306 int retval;
307 int i1 = 0, i2 = 0;
308
309 assert(array1->sorted == array1->nr);
310 assert(array2->sorted == array2->nr);
311 while (i1 < array1->nr && i2 < array2->nr) {
312 struct ref_entry *e1 = array1->refs[i1];
313 struct ref_entry *e2 = array2->refs[i2];
314 int cmp = strcmp(e1->name, e2->name);
315 if (cmp < 0) {
316 retval = do_one_ref(base, fn, trim, flags, cb_data, e1);
317 i1++;
318 } else {
319 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
320 i2++;
321 if (cmp == 0) {
322 /*
323 * There was a ref in array1 with the
324 * same name; ignore it.
325 */
326 i1++;
327 }
328 }
329 if (retval)
330 return retval;
331 }
332 if (i1 < array1->nr)
333 return do_for_each_ref_in_array(array1, i1,
334 base, fn, trim, flags, cb_data);
335 if (i2 < array2->nr)
336 return do_for_each_ref_in_array(array2, i2,
337 base, fn, trim, flags, cb_data);
338 return 0;
339}
340
d66da478
MH
341/*
342 * Return true iff refname1 and refname2 conflict with each other.
343 * Two reference names conflict if one of them exactly matches the
344 * leading components of the other; e.g., "foo/bar" conflicts with
345 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
346 * "foo/barbados".
347 */
348static int names_conflict(const char *refname1, const char *refname2)
349{
5a4d4947
MH
350 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
351 ;
352 return (*refname1 == '\0' && *refname2 == '/')
353 || (*refname1 == '/' && *refname2 == '\0');
354}
355
356struct name_conflict_cb {
357 const char *refname;
358 const char *oldrefname;
359 const char *conflicting_refname;
360};
361
362static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
363 int flags, void *cb_data)
364{
365 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
366 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
367 return 0;
368 if (names_conflict(data->refname, existingrefname)) {
369 data->conflicting_refname = existingrefname;
370 return 1;
d66da478 371 }
5a4d4947 372 return 0;
d66da478
MH
373}
374
bc5fd6d3
MH
375/*
376 * Return true iff a reference named refname could be created without
5a4d4947
MH
377 * conflicting with the name of an existing reference in array. If
378 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
379 * (e.g., because oldrefname is scheduled for deletion in the same
bc5fd6d3
MH
380 * operation).
381 */
382static int is_refname_available(const char *refname, const char *oldrefname,
383 struct ref_array *array)
384{
5a4d4947
MH
385 struct name_conflict_cb data;
386 data.refname = refname;
387 data.oldrefname = oldrefname;
388 data.conflicting_refname = NULL;
389
390 sort_ref_array(array);
391 if (do_for_each_ref_in_array(array, 0, "", name_conflict_fn,
392 0, DO_FOR_EACH_INCLUDE_BROKEN,
393 &data)) {
394 error("'%s' exists; cannot create '%s'",
395 data.conflicting_refname, refname);
396 return 0;
bc5fd6d3
MH
397 }
398 return 1;
e1e22e37
LT
399}
400
5e290ff7
JH
401/*
402 * Future: need to be in "struct repository"
403 * when doing a full libification.
404 */
79c7ca54
MH
405static struct ref_cache {
406 struct ref_cache *next;
5e290ff7
JH
407 char did_loose;
408 char did_packed;
e9c4c111
JP
409 struct ref_array loose;
410 struct ref_array packed;
ce40979c
MH
411 /* The submodule name, or "" for the main repo. */
412 char name[FLEX_ARRAY];
79c7ca54 413} *ref_cache;
0e88c130 414
760c4512 415static void clear_packed_ref_cache(struct ref_cache *refs)
e1e22e37 416{
1b7edaf9 417 if (refs->did_packed)
7c59511e 418 clear_ref_array(&refs->packed);
760c4512 419 refs->did_packed = 0;
5e290ff7 420}
e1e22e37 421
760c4512
MH
422static void clear_loose_ref_cache(struct ref_cache *refs)
423{
424 if (refs->did_loose)
7c59511e 425 clear_ref_array(&refs->loose);
760c4512
MH
426 refs->did_loose = 0;
427}
428
79c7ca54 429static struct ref_cache *create_ref_cache(const char *submodule)
e5dbf605 430{
ce40979c 431 int len;
79c7ca54 432 struct ref_cache *refs;
ce40979c
MH
433 if (!submodule)
434 submodule = "";
435 len = strlen(submodule) + 1;
79c7ca54 436 refs = xcalloc(1, sizeof(struct ref_cache) + len);
ce40979c 437 memcpy(refs->name, submodule, len);
e5dbf605
MH
438 return refs;
439}
440
4349a668 441/*
79c7ca54 442 * Return a pointer to a ref_cache for the specified submodule. For
4349a668
MH
443 * the main repository, use submodule==NULL. The returned structure
444 * will be allocated and initialized but not necessarily populated; it
445 * should not be freed.
446 */
79c7ca54 447static struct ref_cache *get_ref_cache(const char *submodule)
4349a668 448{
79c7ca54 449 struct ref_cache *refs = ref_cache;
0e88c130
MH
450 if (!submodule)
451 submodule = "";
452 while (refs) {
453 if (!strcmp(submodule, refs->name))
454 return refs;
455 refs = refs->next;
4349a668 456 }
0e88c130 457
79c7ca54
MH
458 refs = create_ref_cache(submodule);
459 refs->next = ref_cache;
460 ref_cache = refs;
0e88c130 461 return refs;
4349a668
MH
462}
463
8be8bde7 464void invalidate_ref_cache(const char *submodule)
f130b116 465{
c5f29abd
MH
466 struct ref_cache *refs = get_ref_cache(submodule);
467 clear_packed_ref_cache(refs);
468 clear_loose_ref_cache(refs);
5e290ff7 469}
e1e22e37 470
bc5fd6d3
MH
471/*
472 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
473 * Return a pointer to the refname within the line (null-terminated),
474 * or NULL if there was a problem.
475 */
476static const char *parse_ref_line(char *line, unsigned char *sha1)
477{
478 /*
479 * 42: the answer to everything.
480 *
481 * In this case, it happens to be the answer to
482 * 40 (length of sha1 hex representation)
483 * +1 (space in between hex and name)
484 * +1 (newline at the end of the line)
485 */
486 int len = strlen(line) - 42;
487
488 if (len <= 0)
489 return NULL;
490 if (get_sha1_hex(line, sha1) < 0)
491 return NULL;
492 if (!isspace(line[40]))
493 return NULL;
494 line += 41;
495 if (isspace(*line))
496 return NULL;
497 if (line[len] != '\n')
498 return NULL;
499 line[len] = 0;
500
501 return line;
502}
503
2c5c66be 504static void read_packed_refs(FILE *f, struct ref_array *array)
f4204ab9 505{
e9c4c111 506 struct ref_entry *last = NULL;
f4204ab9
JH
507 char refline[PATH_MAX];
508 int flag = REF_ISPACKED;
509
510 while (fgets(refline, sizeof(refline), f)) {
511 unsigned char sha1[20];
dfefa935 512 const char *refname;
f4204ab9
JH
513 static const char header[] = "# pack-refs with:";
514
515 if (!strncmp(refline, header, sizeof(header)-1)) {
516 const char *traits = refline + sizeof(header) - 1;
517 if (strstr(traits, " peeled "))
518 flag |= REF_KNOWS_PEELED;
519 /* perhaps other traits later as well */
520 continue;
521 }
522
dfefa935
MH
523 refname = parse_ref_line(refline, sha1);
524 if (refname) {
dd73ecd1
MH
525 last = create_ref_entry(refname, sha1, flag, 1);
526 add_ref(array, last);
f4204ab9
JH
527 continue;
528 }
529 if (last &&
530 refline[0] == '^' &&
531 strlen(refline) == 42 &&
532 refline[41] == '\n' &&
533 !get_sha1_hex(refline + 1, sha1))
534 hashcpy(last->peeled, sha1);
535 }
f4204ab9
JH
536}
537
316b097a 538static struct ref_array *get_packed_refs(struct ref_cache *refs)
5e290ff7 539{
4349a668
MH
540 if (!refs->did_packed) {
541 const char *packed_refs_file;
542 FILE *f;
0bad611b 543
316b097a
MH
544 if (*refs->name)
545 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
4349a668
MH
546 else
547 packed_refs_file = git_path("packed-refs");
548 f = fopen(packed_refs_file, "r");
e1e22e37 549 if (f) {
2c5c66be 550 read_packed_refs(f, &refs->packed);
e1e22e37 551 fclose(f);
e1e22e37 552 }
0bad611b 553 refs->did_packed = 1;
e1e22e37 554 }
e9c4c111 555 return &refs->packed;
e1e22e37
LT
556}
557
30249ee6
MH
558void add_packed_ref(const char *refname, const unsigned char *sha1)
559{
560 add_ref(get_packed_refs(get_ref_cache(NULL)),
561 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
562}
563
3b124823 564static void get_ref_dir(struct ref_cache *refs, const char *base,
e9c4c111 565 struct ref_array *array)
e1e22e37 566{
0bad611b
HV
567 DIR *dir;
568 const char *path;
569
3b124823
MH
570 if (*refs->name)
571 path = git_path_submodule(refs->name, "%s", base);
0bad611b
HV
572 else
573 path = git_path("%s", base);
574
0bad611b 575 dir = opendir(path);
e1e22e37
LT
576
577 if (dir) {
578 struct dirent *de;
579 int baselen = strlen(base);
dfefa935 580 char *refname = xmalloc(baselen + 257);
e1e22e37 581
dfefa935 582 memcpy(refname, base, baselen);
e1e22e37 583 if (baselen && base[baselen-1] != '/')
dfefa935 584 refname[baselen++] = '/';
e1e22e37
LT
585
586 while ((de = readdir(dir)) != NULL) {
587 unsigned char sha1[20];
588 struct stat st;
8da19775 589 int flag;
e1e22e37 590 int namelen;
0bad611b 591 const char *refdir;
e1e22e37
LT
592
593 if (de->d_name[0] == '.')
594 continue;
595 namelen = strlen(de->d_name);
596 if (namelen > 255)
597 continue;
598 if (has_extension(de->d_name, ".lock"))
599 continue;
dfefa935 600 memcpy(refname + baselen, de->d_name, namelen+1);
3b124823
MH
601 refdir = *refs->name
602 ? git_path_submodule(refs->name, "%s", refname)
dfefa935 603 : git_path("%s", refname);
0bad611b 604 if (stat(refdir, &st) < 0)
e1e22e37
LT
605 continue;
606 if (S_ISDIR(st.st_mode)) {
3b124823 607 get_ref_dir(refs, refname, array);
e1e22e37
LT
608 continue;
609 }
3b124823 610 if (*refs->name) {
f8948e2f 611 hashclr(sha1);
0bad611b 612 flag = 0;
3b124823 613 if (resolve_gitlink_ref(refs->name, refname, sha1) < 0) {
0bad611b 614 hashclr(sha1);
98ac34b2 615 flag |= REF_ISBROKEN;
0bad611b 616 }
dfefa935 617 } else if (read_ref_full(refname, sha1, 1, &flag)) {
09116a1c
JH
618 hashclr(sha1);
619 flag |= REF_ISBROKEN;
620 }
dd73ecd1 621 add_ref(array, create_ref_entry(refname, sha1, flag, 1));
e1e22e37 622 }
dfefa935 623 free(refname);
e1e22e37
LT
624 closedir(dir);
625 }
e1e22e37
LT
626}
627
316b097a 628static struct ref_array *get_loose_refs(struct ref_cache *refs)
e1e22e37 629{
4349a668 630 if (!refs->did_loose) {
3b124823 631 get_ref_dir(refs, "refs", &refs->loose);
4349a668 632 refs->did_loose = 1;
e1e22e37 633 }
2c5c66be 634 return &refs->loose;
e1e22e37
LT
635}
636
ca8db142
LT
637/* We allow "recursive" symbolic refs. Only within reason, though */
638#define MAXDEPTH 5
0ebde32c
LT
639#define MAXREFLEN (1024)
640
e5fa45c1
JH
641/*
642 * Called by resolve_gitlink_ref_recursive() after it failed to read
b0626608
MH
643 * from the loose refs in ref_cache refs. Find <refname> in the
644 * packed-refs file for the submodule.
e5fa45c1 645 */
b0626608 646static int resolve_gitlink_packed_ref(struct ref_cache *refs,
85be1fe3 647 const char *refname, unsigned char *sha1)
0ebde32c 648{
2c5c66be 649 struct ref_entry *ref;
b0626608 650 struct ref_array *array = get_packed_refs(refs);
0ebde32c 651
2c5c66be 652 ref = search_ref_array(array, refname);
b0626608
MH
653 if (ref == NULL)
654 return -1;
655
656 memcpy(sha1, ref->sha1, 20);
657 return 0;
0ebde32c
LT
658}
659
b0626608 660static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
85be1fe3 661 const char *refname, unsigned char *sha1,
dfefa935 662 int recursion)
0ebde32c 663{
064d51dc 664 int fd, len;
0ebde32c 665 char buffer[128], *p;
064d51dc 666 char *path;
0ebde32c 667
064d51dc 668 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
0ebde32c 669 return -1;
064d51dc
MH
670 path = *refs->name
671 ? git_path_submodule(refs->name, "%s", refname)
672 : git_path("%s", refname);
673 fd = open(path, O_RDONLY);
0ebde32c 674 if (fd < 0)
b0626608 675 return resolve_gitlink_packed_ref(refs, refname, sha1);
0ebde32c
LT
676
677 len = read(fd, buffer, sizeof(buffer)-1);
678 close(fd);
679 if (len < 0)
680 return -1;
681 while (len && isspace(buffer[len-1]))
682 len--;
683 buffer[len] = 0;
684
685 /* Was it a detached head or an old-fashioned symlink? */
85be1fe3 686 if (!get_sha1_hex(buffer, sha1))
0ebde32c
LT
687 return 0;
688
689 /* Symref? */
690 if (strncmp(buffer, "ref:", 4))
691 return -1;
692 p = buffer + 4;
693 while (isspace(*p))
694 p++;
695
064d51dc 696 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
0ebde32c
LT
697}
698
85be1fe3 699int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
0ebde32c
LT
700{
701 int len = strlen(path), retval;
064d51dc 702 char *submodule;
b0626608 703 struct ref_cache *refs;
0ebde32c
LT
704
705 while (len && path[len-1] == '/')
706 len--;
707 if (!len)
708 return -1;
b0626608
MH
709 submodule = xstrndup(path, len);
710 refs = get_ref_cache(submodule);
711 free(submodule);
712
064d51dc 713 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
0ebde32c
LT
714 return retval;
715}
ca8db142 716
4886b89f 717/*
c224ca7f
MH
718 * Try to read ref from the packed references. On success, set sha1
719 * and return 0; otherwise, return -1.
4886b89f 720 */
dfefa935 721static int get_packed_ref(const char *refname, unsigned char *sha1)
c224ca7f 722{
316b097a 723 struct ref_array *packed = get_packed_refs(get_ref_cache(NULL));
dfefa935 724 struct ref_entry *entry = search_ref_array(packed, refname);
2c5c66be
JH
725 if (entry) {
726 hashcpy(sha1, entry->sha1);
727 return 0;
c224ca7f
MH
728 }
729 return -1;
730}
731
8d68493f 732const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
8a65ff76 733{
0104ca09
HO
734 int depth = MAXDEPTH;
735 ssize_t len;
a876ed83 736 char buffer[256];
dfefa935 737 static char refname_buffer[256];
ca8db142 738
8da19775
JH
739 if (flag)
740 *flag = 0;
741
dfefa935 742 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
8384d788
MH
743 return NULL;
744
a876ed83 745 for (;;) {
55956350 746 char path[PATH_MAX];
a876ed83
JH
747 struct stat st;
748 char *buf;
749 int fd;
8a65ff76 750
a876ed83
JH
751 if (--depth < 0)
752 return NULL;
ca8db142 753
dfefa935 754 git_snpath(path, sizeof(path), "%s", refname);
c224ca7f 755
a876ed83 756 if (lstat(path, &st) < 0) {
c224ca7f
MH
757 if (errno != ENOENT)
758 return NULL;
759 /*
760 * The loose reference file does not exist;
761 * check for a packed reference.
762 */
dfefa935 763 if (!get_packed_ref(refname, sha1)) {
c224ca7f
MH
764 if (flag)
765 *flag |= REF_ISPACKED;
dfefa935 766 return refname;
434cd0cd 767 }
c224ca7f
MH
768 /* The reference is not a packed reference, either. */
769 if (reading) {
a876ed83 770 return NULL;
c224ca7f
MH
771 } else {
772 hashclr(sha1);
dfefa935 773 return refname;
c224ca7f 774 }
a876ed83 775 }
ca8db142 776
a876ed83
JH
777 /* Follow "normalized" - ie "refs/.." symlinks by hand */
778 if (S_ISLNK(st.st_mode)) {
779 len = readlink(path, buffer, sizeof(buffer)-1);
7bb2bf8e
MH
780 if (len < 0)
781 return NULL;
b54cb795 782 buffer[len] = 0;
1f58a038
MH
783 if (!prefixcmp(buffer, "refs/") &&
784 !check_refname_format(buffer, 0)) {
dfefa935
MH
785 strcpy(refname_buffer, buffer);
786 refname = refname_buffer;
8da19775
JH
787 if (flag)
788 *flag |= REF_ISSYMREF;
a876ed83
JH
789 continue;
790 }
ca8db142 791 }
a876ed83 792
7a21632f
DS
793 /* Is it a directory? */
794 if (S_ISDIR(st.st_mode)) {
795 errno = EISDIR;
796 return NULL;
797 }
798
a876ed83
JH
799 /*
800 * Anything else, just open it and try to use it as
801 * a ref
802 */
803 fd = open(path, O_RDONLY);
804 if (fd < 0)
805 return NULL;
93d26e4c 806 len = read_in_full(fd, buffer, sizeof(buffer)-1);
a876ed83 807 close(fd);
28775050
MH
808 if (len < 0)
809 return NULL;
810 while (len && isspace(buffer[len-1]))
811 len--;
812 buffer[len] = '\0';
a876ed83
JH
813
814 /*
815 * Is it a symbolic ref?
816 */
28775050 817 if (prefixcmp(buffer, "ref:"))
a876ed83 818 break;
55956350
JH
819 if (flag)
820 *flag |= REF_ISSYMREF;
a876ed83 821 buf = buffer + 4;
28775050
MH
822 while (isspace(*buf))
823 buf++;
313fb010 824 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
55956350
JH
825 if (flag)
826 *flag |= REF_ISBROKEN;
313fb010
MH
827 return NULL;
828 }
dfefa935 829 refname = strcpy(refname_buffer, buf);
8a65ff76 830 }
f989fea0
MH
831 /* Please note that FETCH_HEAD has a second line containing other data. */
832 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
55956350
JH
833 if (flag)
834 *flag |= REF_ISBROKEN;
a876ed83 835 return NULL;
629cd3ac 836 }
dfefa935 837 return refname;
a876ed83
JH
838}
839
96ec7b1e
NTND
840char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
841{
8cad4744 842 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
96ec7b1e
NTND
843 return ret ? xstrdup(ret) : NULL;
844}
845
d08bae7e
IL
846/* The argument to filter_refs */
847struct ref_filter {
848 const char *pattern;
849 each_ref_fn *fn;
850 void *cb_data;
851};
852
dfefa935 853int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
a876ed83 854{
8d68493f 855 if (resolve_ref_unsafe(refname, sha1, reading, flags))
a876ed83
JH
856 return 0;
857 return -1;
8a65ff76
LT
858}
859
dfefa935 860int read_ref(const char *refname, unsigned char *sha1)
c6893323 861{
dfefa935 862 return read_ref_full(refname, sha1, 1, NULL);
c6893323
NTND
863}
864
bc5fd6d3 865int ref_exists(const char *refname)
ef06b918 866{
bc5fd6d3
MH
867 unsigned char sha1[20];
868 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
ef06b918
JH
869}
870
85be1fe3 871static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
dfefa935 872 void *data)
d08bae7e
IL
873{
874 struct ref_filter *filter = (struct ref_filter *)data;
dfefa935 875 if (fnmatch(filter->pattern, refname, 0))
d08bae7e 876 return 0;
85be1fe3 877 return filter->fn(refname, sha1, flags, filter->cb_data);
d08bae7e
IL
878}
879
dfefa935 880int peel_ref(const char *refname, unsigned char *sha1)
cf0adba7
JH
881{
882 int flag;
883 unsigned char base[20];
884 struct object *o;
885
dfefa935
MH
886 if (current_ref && (current_ref->name == refname
887 || !strcmp(current_ref->name, refname))) {
0ae91be0
SP
888 if (current_ref->flag & REF_KNOWS_PEELED) {
889 hashcpy(sha1, current_ref->peeled);
890 return 0;
891 }
892 hashcpy(base, current_ref->sha1);
893 goto fallback;
894 }
895
dfefa935 896 if (read_ref_full(refname, base, 1, &flag))
cf0adba7
JH
897 return -1;
898
899 if ((flag & REF_ISPACKED)) {
316b097a 900 struct ref_array *array = get_packed_refs(get_ref_cache(NULL));
dfefa935 901 struct ref_entry *r = search_ref_array(array, refname);
cf0adba7 902
e9c4c111
JP
903 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
904 hashcpy(sha1, r->peeled);
905 return 0;
cf0adba7 906 }
cf0adba7
JH
907 }
908
0ae91be0 909fallback:
cf0adba7 910 o = parse_object(base);
8c87dc77 911 if (o && o->type == OBJ_TAG) {
dfefa935 912 o = deref_tag(o, refname, 0);
cf0adba7
JH
913 if (o) {
914 hashcpy(sha1, o->sha1);
915 return 0;
916 }
917 }
918 return -1;
919}
920
bc5fd6d3
MH
921struct warn_if_dangling_data {
922 FILE *fp;
923 const char *refname;
924 const char *msg_fmt;
925};
926
927static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
928 int flags, void *cb_data)
929{
930 struct warn_if_dangling_data *d = cb_data;
931 const char *resolves_to;
932 unsigned char junk[20];
933
934 if (!(flags & REF_ISSYMREF))
935 return 0;
936
937 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
938 if (!resolves_to || strcmp(resolves_to, d->refname))
939 return 0;
940
941 fprintf(d->fp, d->msg_fmt, refname);
942 return 0;
943}
944
945void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
946{
947 struct warn_if_dangling_data data;
948
949 data.fp = fp;
950 data.refname = refname;
951 data.msg_fmt = msg_fmt;
952 for_each_rawref(warn_if_dangling_symref, &data);
953}
954
0bad611b
HV
955static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
956 int trim, int flags, void *cb_data)
8a65ff76 957{
316b097a 958 struct ref_cache *refs = get_ref_cache(submodule);
b3fd060f
MH
959 struct ref_array *packed_refs = get_packed_refs(refs);
960 struct ref_array *loose_refs = get_loose_refs(refs);
961 sort_ref_array(packed_refs);
962 sort_ref_array(loose_refs);
963 return do_for_each_ref_in_arrays(packed_refs,
964 loose_refs,
965 base, fn, trim, flags, cb_data);
8a65ff76
LT
966}
967
0bad611b 968static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
723c31fe
LT
969{
970 unsigned char sha1[20];
8da19775
JH
971 int flag;
972
0bad611b
HV
973 if (submodule) {
974 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
975 return fn("HEAD", sha1, 0, cb_data);
976
977 return 0;
978 }
979
c6893323 980 if (!read_ref_full("HEAD", sha1, 1, &flag))
8da19775 981 return fn("HEAD", sha1, flag, cb_data);
0bad611b 982
2f34ba32 983 return 0;
723c31fe
LT
984}
985
0bad611b
HV
986int head_ref(each_ref_fn fn, void *cb_data)
987{
988 return do_head_ref(NULL, fn, cb_data);
989}
990
9ef6aeb0
HV
991int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
992{
993 return do_head_ref(submodule, fn, cb_data);
994}
995
cb5d709f 996int for_each_ref(each_ref_fn fn, void *cb_data)
8a65ff76 997{
b3cfc406 998 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
a62be77f
SE
999}
1000
9ef6aeb0
HV
1001int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1002{
b3cfc406 1003 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
a62be77f
SE
1004}
1005
2a8177b6
CC
1006int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1007{
0bad611b 1008 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1009}
1010
9ef6aeb0
HV
1011int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1012 each_ref_fn fn, void *cb_data)
1013{
1014 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
2a8177b6
CC
1015}
1016
cb5d709f 1017int for_each_tag_ref(each_ref_fn fn, void *cb_data)
a62be77f 1018{
2a8177b6 1019 return for_each_ref_in("refs/tags/", fn, cb_data);
a62be77f
SE
1020}
1021
9ef6aeb0
HV
1022int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1023{
1024 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1025}
1026
cb5d709f 1027int for_each_branch_ref(each_ref_fn fn, void *cb_data)
a62be77f 1028{
2a8177b6 1029 return for_each_ref_in("refs/heads/", fn, cb_data);
a62be77f
SE
1030}
1031
9ef6aeb0
HV
1032int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1033{
1034 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1035}
1036
cb5d709f 1037int for_each_remote_ref(each_ref_fn fn, void *cb_data)
a62be77f 1038{
2a8177b6 1039 return for_each_ref_in("refs/remotes/", fn, cb_data);
f8948e2f
JH
1040}
1041
9ef6aeb0
HV
1042int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1043{
1044 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1045}
1046
29268700
CC
1047int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1048{
0bad611b 1049 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
29268700
CC
1050}
1051
a1bea2c1
JT
1052int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1053{
1054 struct strbuf buf = STRBUF_INIT;
1055 int ret = 0;
1056 unsigned char sha1[20];
1057 int flag;
1058
1059 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
c6893323 1060 if (!read_ref_full(buf.buf, sha1, 1, &flag))
a1bea2c1
JT
1061 ret = fn(buf.buf, sha1, flag, cb_data);
1062 strbuf_release(&buf);
1063
1064 return ret;
1065}
1066
1067int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1068{
1069 struct strbuf buf = STRBUF_INIT;
1070 int ret;
1071 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1072 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1073 strbuf_release(&buf);
1074 return ret;
1075}
1076
b09fe971
IL
1077int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1078 const char *prefix, void *cb_data)
d08bae7e
IL
1079{
1080 struct strbuf real_pattern = STRBUF_INIT;
1081 struct ref_filter filter;
d08bae7e
IL
1082 int ret;
1083
b09fe971 1084 if (!prefix && prefixcmp(pattern, "refs/"))
d08bae7e 1085 strbuf_addstr(&real_pattern, "refs/");
b09fe971
IL
1086 else if (prefix)
1087 strbuf_addstr(&real_pattern, prefix);
d08bae7e
IL
1088 strbuf_addstr(&real_pattern, pattern);
1089
894a9d33 1090 if (!has_glob_specials(pattern)) {
9517e6b8 1091 /* Append implied '/' '*' if not present. */
d08bae7e
IL
1092 if (real_pattern.buf[real_pattern.len - 1] != '/')
1093 strbuf_addch(&real_pattern, '/');
1094 /* No need to check for '*', there is none. */
1095 strbuf_addch(&real_pattern, '*');
1096 }
1097
1098 filter.pattern = real_pattern.buf;
1099 filter.fn = fn;
1100 filter.cb_data = cb_data;
1101 ret = for_each_ref(filter_refs, &filter);
1102
1103 strbuf_release(&real_pattern);
1104 return ret;
1105}
1106
b09fe971
IL
1107int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1108{
1109 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1110}
1111
f8948e2f
JH
1112int for_each_rawref(each_ref_fn fn, void *cb_data)
1113{
b3cfc406 1114 return do_for_each_ref(NULL, "", fn, 0,
f8948e2f 1115 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
8a65ff76
LT
1116}
1117
4577e483 1118const char *prettify_refname(const char *name)
a9c37a72 1119{
a9c37a72
DB
1120 return name + (
1121 !prefixcmp(name, "refs/heads/") ? 11 :
1122 !prefixcmp(name, "refs/tags/") ? 10 :
1123 !prefixcmp(name, "refs/remotes/") ? 13 :
1124 0);
1125}
1126
79803322
SP
1127const char *ref_rev_parse_rules[] = {
1128 "%.*s",
1129 "refs/%.*s",
1130 "refs/tags/%.*s",
1131 "refs/heads/%.*s",
1132 "refs/remotes/%.*s",
1133 "refs/remotes/%.*s/HEAD",
1134 NULL
1135};
1136
1137int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1138{
1139 const char **p;
1140 const int abbrev_name_len = strlen(abbrev_name);
1141
1142 for (p = rules; *p; p++) {
1143 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1144 return 1;
1145 }
1146 }
1147
1148 return 0;
1149}
1150
e5f38ec3 1151static struct ref_lock *verify_lock(struct ref_lock *lock,
4bd18c43
SP
1152 const unsigned char *old_sha1, int mustexist)
1153{
c6893323 1154 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
434cd0cd 1155 error("Can't verify ref %s", lock->ref_name);
4bd18c43
SP
1156 unlock_ref(lock);
1157 return NULL;
1158 }
a89fccd2 1159 if (hashcmp(lock->old_sha1, old_sha1)) {
434cd0cd 1160 error("Ref %s is at %s but expected %s", lock->ref_name,
4bd18c43
SP
1161 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1162 unlock_ref(lock);
1163 return NULL;
1164 }
1165 return lock;
1166}
1167
7155b727 1168static int remove_empty_directories(const char *file)
bc7127ef
JH
1169{
1170 /* we want to create a file but there is a directory there;
1171 * if that is an empty directory (or a directory that contains
1172 * only empty directories), remove them.
1173 */
7155b727
JS
1174 struct strbuf path;
1175 int result;
bc7127ef 1176
7155b727
JS
1177 strbuf_init(&path, 20);
1178 strbuf_addstr(&path, file);
1179
a0f4afbe 1180 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
7155b727
JS
1181
1182 strbuf_release(&path);
1183
1184 return result;
bc7127ef
JH
1185}
1186
ff74f7f1
JH
1187/*
1188 * *string and *len will only be substituted, and *string returned (for
1189 * later free()ing) if the string passed in is a magic short-hand form
1190 * to name a branch.
1191 */
1192static char *substitute_branch_name(const char **string, int *len)
1193{
1194 struct strbuf buf = STRBUF_INIT;
1195 int ret = interpret_branch_name(*string, &buf);
1196
1197 if (ret == *len) {
1198 size_t size;
1199 *string = strbuf_detach(&buf, &size);
1200 *len = size;
1201 return (char *)*string;
1202 }
1203
1204 return NULL;
1205}
1206
1207int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1208{
1209 char *last_branch = substitute_branch_name(&str, &len);
1210 const char **p, *r;
1211 int refs_found = 0;
1212
1213 *ref = NULL;
1214 for (p = ref_rev_parse_rules; *p; p++) {
1215 char fullref[PATH_MAX];
1216 unsigned char sha1_from_ref[20];
1217 unsigned char *this_result;
1218 int flag;
1219
1220 this_result = refs_found ? sha1_from_ref : sha1;
1221 mksnpath(fullref, sizeof(fullref), *p, len, str);
8cad4744 1222 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
ff74f7f1
JH
1223 if (r) {
1224 if (!refs_found++)
1225 *ref = xstrdup(r);
1226 if (!warn_ambiguous_refs)
1227 break;
55956350 1228 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
ff74f7f1 1229 warning("ignoring dangling symref %s.", fullref);
55956350
JH
1230 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1231 warning("ignoring broken ref %s.", fullref);
1232 }
ff74f7f1
JH
1233 }
1234 free(last_branch);
1235 return refs_found;
1236}
1237
1238int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1239{
1240 char *last_branch = substitute_branch_name(&str, &len);
1241 const char **p;
1242 int logs_found = 0;
1243
1244 *log = NULL;
1245 for (p = ref_rev_parse_rules; *p; p++) {
1246 struct stat st;
1247 unsigned char hash[20];
1248 char path[PATH_MAX];
1249 const char *ref, *it;
1250
1251 mksnpath(path, sizeof(path), *p, len, str);
8cad4744 1252 ref = resolve_ref_unsafe(path, hash, 1, NULL);
ff74f7f1
JH
1253 if (!ref)
1254 continue;
1255 if (!stat(git_path("logs/%s", path), &st) &&
1256 S_ISREG(st.st_mode))
1257 it = path;
1258 else if (strcmp(ref, path) &&
1259 !stat(git_path("logs/%s", ref), &st) &&
1260 S_ISREG(st.st_mode))
1261 it = ref;
1262 else
1263 continue;
1264 if (!logs_found++) {
1265 *log = xstrdup(it);
1266 hashcpy(sha1, hash);
1267 }
1268 if (!warn_ambiguous_refs)
1269 break;
1270 }
1271 free(last_branch);
1272 return logs_found;
1273}
1274
dfefa935
MH
1275static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1276 const unsigned char *old_sha1,
1277 int flags, int *type_p)
4bd18c43 1278{
434cd0cd 1279 char *ref_file;
dfefa935 1280 const char *orig_refname = refname;
4bd18c43 1281 struct ref_lock *lock;
5cc3cef9 1282 int last_errno = 0;
acd3b9ec 1283 int type, lflags;
4431fcc4 1284 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
5bdd8d4a 1285 int missing = 0;
4bd18c43
SP
1286
1287 lock = xcalloc(1, sizeof(struct ref_lock));
1288 lock->lock_fd = -1;
1289
8d68493f 1290 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
dfefa935 1291 if (!refname && errno == EISDIR) {
bc7127ef
JH
1292 /* we are trying to lock foo but we used to
1293 * have foo/bar which now does not exist;
1294 * it is normal for the empty directory 'foo'
1295 * to remain.
1296 */
dfefa935 1297 ref_file = git_path("%s", orig_refname);
5cc3cef9
JH
1298 if (remove_empty_directories(ref_file)) {
1299 last_errno = errno;
dfefa935 1300 error("there are still refs under '%s'", orig_refname);
5cc3cef9
JH
1301 goto error_return;
1302 }
8d68493f 1303 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
bc7127ef 1304 }
68db31cc
SV
1305 if (type_p)
1306 *type_p = type;
dfefa935 1307 if (!refname) {
5cc3cef9 1308 last_errno = errno;
818f477c 1309 error("unable to resolve reference %s: %s",
dfefa935 1310 orig_refname, strerror(errno));
5cc3cef9 1311 goto error_return;
4bd18c43 1312 }
5bdd8d4a 1313 missing = is_null_sha1(lock->old_sha1);
c976d415
LH
1314 /* When the ref did not exist and we are creating it,
1315 * make sure there is no existing ref that is packed
1316 * whose name begins with our refname, nor a ref whose
1317 * name is a proper prefix of our refname.
1318 */
5bdd8d4a 1319 if (missing &&
316b097a 1320 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
f475e08e 1321 last_errno = ENOTDIR;
c976d415 1322 goto error_return;
f475e08e 1323 }
22a3844e 1324
c33d5174 1325 lock->lk = xcalloc(1, sizeof(struct lock_file));
4bd18c43 1326
acd3b9ec
JH
1327 lflags = LOCK_DIE_ON_ERROR;
1328 if (flags & REF_NODEREF) {
dfefa935 1329 refname = orig_refname;
acd3b9ec
JH
1330 lflags |= LOCK_NODEREF;
1331 }
dfefa935
MH
1332 lock->ref_name = xstrdup(refname);
1333 lock->orig_ref_name = xstrdup(orig_refname);
1334 ref_file = git_path("%s", refname);
5bdd8d4a 1335 if (missing)
68db31cc
SV
1336 lock->force_write = 1;
1337 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1338 lock->force_write = 1;
4bd18c43 1339
5cc3cef9
JH
1340 if (safe_create_leading_directories(ref_file)) {
1341 last_errno = errno;
1342 error("unable to create directory for %s", ref_file);
1343 goto error_return;
1344 }
4bd18c43 1345
acd3b9ec 1346 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
4bd18c43 1347 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
5cc3cef9
JH
1348
1349 error_return:
1350 unlock_ref(lock);
1351 errno = last_errno;
1352 return NULL;
4bd18c43
SP
1353}
1354
dfefa935 1355struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
95fc7512 1356{
53cce84c 1357 char refpath[PATH_MAX];
dfefa935 1358 if (check_refname_format(refname, 0))
4bd18c43 1359 return NULL;
dfefa935 1360 strcpy(refpath, mkpath("refs/%s", refname));
68db31cc 1361 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
4bd18c43
SP
1362}
1363
dfefa935
MH
1364struct ref_lock *lock_any_ref_for_update(const char *refname,
1365 const unsigned char *old_sha1, int flags)
4bd18c43 1366{
dfefa935 1367 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
257f3020 1368 return NULL;
dfefa935 1369 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
c0277d15
JH
1370}
1371
d66da478
MH
1372struct repack_without_ref_sb {
1373 const char *refname;
1374 int fd;
1375};
1376
1377static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1378 int flags, void *cb_data)
1379{
1380 struct repack_without_ref_sb *data = cb_data;
1381 char line[PATH_MAX + 100];
1382 int len;
1383
1384 if (!strcmp(data->refname, refname))
1385 return 0;
1386 len = snprintf(line, sizeof(line), "%s %s\n",
1387 sha1_to_hex(sha1), refname);
1388 /* this should not happen but just being defensive */
1389 if (len > sizeof(line))
1390 die("too long a refname '%s'", refname);
1391 write_or_die(data->fd, line, len);
1392 return 0;
1393}
1394
26a063a1
JH
1395static struct lock_file packlock;
1396
c0277d15
JH
1397static int repack_without_ref(const char *refname)
1398{
d66da478
MH
1399 struct repack_without_ref_sb data;
1400 struct ref_array *packed = get_packed_refs(get_ref_cache(NULL));
1401 sort_ref_array(packed);
fe9c7b78 1402 if (search_ref_array(packed, refname) == NULL)
c0277d15 1403 return 0;
d66da478
MH
1404 data.refname = refname;
1405 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1406 if (data.fd < 0) {
1b018fd9 1407 unable_to_lock_error(git_path("packed-refs"), errno);
c0277d15 1408 return error("cannot delete '%s' from packed refs", refname);
1b018fd9 1409 }
d66da478 1410 do_for_each_ref_in_array(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
c0277d15
JH
1411 return commit_lock_file(&packlock);
1412}
1413
eca35a25 1414int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
c0277d15
JH
1415{
1416 struct ref_lock *lock;
eca35a25 1417 int err, i = 0, ret = 0, flag = 0;
c0277d15 1418
68db31cc 1419 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
c0277d15
JH
1420 if (!lock)
1421 return 1;
045a476f 1422 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
c0277d15 1423 /* loose */
eca35a25
MV
1424 const char *path;
1425
1426 if (!(delopt & REF_NODEREF)) {
1427 i = strlen(lock->lk->filename) - 5; /* .lock */
1428 lock->lk->filename[i] = 0;
1429 path = lock->lk->filename;
1430 } else {
9db56f71 1431 path = git_path("%s", refname);
eca35a25 1432 }
691f1a28
AR
1433 err = unlink_or_warn(path);
1434 if (err && errno != ENOENT)
c0277d15 1435 ret = 1;
691f1a28 1436
eca35a25
MV
1437 if (!(delopt & REF_NODEREF))
1438 lock->lk->filename[i] = '.';
c0277d15
JH
1439 }
1440 /* removing the loose one could have resurrected an earlier
1441 * packed one. Also, if it was not loose we need to repack
1442 * without it.
1443 */
1444 ret |= repack_without_ref(refname);
1445
691f1a28 1446 unlink_or_warn(git_path("logs/%s", lock->ref_name));
3870a0d1 1447 invalidate_ref_cache(NULL);
c0277d15
JH
1448 unlock_ref(lock);
1449 return ret;
4bd18c43
SP
1450}
1451
765c2258
PH
1452/*
1453 * People using contrib's git-new-workdir have .git/logs/refs ->
1454 * /some/other/path/.git/logs/refs, and that may live on another device.
1455 *
1456 * IOW, to avoid cross device rename errors, the temporary renamed log must
1457 * live into logs/refs.
1458 */
1459#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1460
dfefa935 1461int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
c976d415 1462{
c976d415
LH
1463 unsigned char sha1[20], orig_sha1[20];
1464 int flag = 0, logmoved = 0;
1465 struct ref_lock *lock;
c976d415 1466 struct stat loginfo;
dfefa935 1467 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
eca35a25 1468 const char *symref = NULL;
316b097a 1469 struct ref_cache *refs = get_ref_cache(NULL);
c976d415 1470
450d4c0f 1471 if (log && S_ISLNK(loginfo.st_mode))
dfefa935 1472 return error("reflog for %s is a symlink", oldrefname);
c976d415 1473
8d68493f 1474 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
eca35a25 1475 if (flag & REF_ISSYMREF)
fa58186c 1476 return error("refname %s is a symbolic ref, renaming it is not supported",
dfefa935 1477 oldrefname);
eca35a25 1478 if (!symref)
dfefa935 1479 return error("refname %s not found", oldrefname);
c976d415 1480
316b097a 1481 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
c976d415
LH
1482 return 1;
1483
316b097a 1484 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
c976d415
LH
1485 return 1;
1486
dfefa935 1487 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
765c2258 1488 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
dfefa935 1489 oldrefname, strerror(errno));
c976d415 1490
dfefa935
MH
1491 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1492 error("unable to delete old %s", oldrefname);
c976d415
LH
1493 goto rollback;
1494 }
1495
dfefa935
MH
1496 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1497 delete_ref(newrefname, sha1, REF_NODEREF)) {
c976d415 1498 if (errno==EISDIR) {
dfefa935
MH
1499 if (remove_empty_directories(git_path("%s", newrefname))) {
1500 error("Directory not empty: %s", newrefname);
c976d415
LH
1501 goto rollback;
1502 }
1503 } else {
dfefa935 1504 error("unable to delete existing %s", newrefname);
c976d415
LH
1505 goto rollback;
1506 }
1507 }
1508
dfefa935
MH
1509 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1510 error("unable to create directory for %s", newrefname);
c976d415
LH
1511 goto rollback;
1512 }
1513
1514 retry:
dfefa935 1515 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
d9e74d57
JR
1516 if (errno==EISDIR || errno==ENOTDIR) {
1517 /*
1518 * rename(a, b) when b is an existing
1519 * directory ought to result in ISDIR, but
1520 * Solaris 5.8 gives ENOTDIR. Sheesh.
1521 */
dfefa935
MH
1522 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1523 error("Directory not empty: logs/%s", newrefname);
c976d415
LH
1524 goto rollback;
1525 }
1526 goto retry;
1527 } else {
765c2258 1528 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
dfefa935 1529 newrefname, strerror(errno));
c976d415
LH
1530 goto rollback;
1531 }
1532 }
1533 logmoved = log;
1534
dfefa935 1535 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
c976d415 1536 if (!lock) {
dfefa935 1537 error("unable to lock %s for update", newrefname);
c976d415
LH
1538 goto rollback;
1539 }
c976d415
LH
1540 lock->force_write = 1;
1541 hashcpy(lock->old_sha1, orig_sha1);
678d0f4c 1542 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
dfefa935 1543 error("unable to write current sha1 into %s", newrefname);
c976d415
LH
1544 goto rollback;
1545 }
1546
1547 return 0;
1548
1549 rollback:
dfefa935 1550 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
c976d415 1551 if (!lock) {
dfefa935 1552 error("unable to lock %s for rollback", oldrefname);
c976d415
LH
1553 goto rollbacklog;
1554 }
1555
1556 lock->force_write = 1;
1557 flag = log_all_ref_updates;
1558 log_all_ref_updates = 0;
1559 if (write_ref_sha1(lock, orig_sha1, NULL))
dfefa935 1560 error("unable to write current sha1 into %s", oldrefname);
c976d415
LH
1561 log_all_ref_updates = flag;
1562
1563 rollbacklog:
dfefa935 1564 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
c976d415 1565 error("unable to restore logfile %s from %s: %s",
dfefa935 1566 oldrefname, newrefname, strerror(errno));
c976d415 1567 if (!logmoved && log &&
dfefa935 1568 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
765c2258 1569 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
dfefa935 1570 oldrefname, strerror(errno));
c976d415
LH
1571
1572 return 1;
1573}
1574
435fc852 1575int close_ref(struct ref_lock *lock)
b531394d
BC
1576{
1577 if (close_lock_file(lock->lk))
1578 return -1;
1579 lock->lock_fd = -1;
1580 return 0;
1581}
1582
435fc852 1583int commit_ref(struct ref_lock *lock)
b531394d
BC
1584{
1585 if (commit_lock_file(lock->lk))
1586 return -1;
1587 lock->lock_fd = -1;
1588 return 0;
1589}
1590
e5f38ec3 1591void unlock_ref(struct ref_lock *lock)
4bd18c43 1592{
4ed7cd3a
BC
1593 /* Do not free lock->lk -- atexit() still looks at them */
1594 if (lock->lk)
1595 rollback_lock_file(lock->lk);
434cd0cd 1596 free(lock->ref_name);
1655707c 1597 free(lock->orig_ref_name);
4bd18c43
SP
1598 free(lock);
1599}
1600
0ec29a47
JH
1601/*
1602 * copy the reflog message msg to buf, which has been allocated sufficiently
1603 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1604 * because reflog file is one line per entry.
1605 */
1606static int copy_msg(char *buf, const char *msg)
1607{
1608 char *cp = buf;
1609 char c;
1610 int wasspace = 1;
1611
1612 *cp++ = '\t';
1613 while ((c = *msg++)) {
1614 if (wasspace && isspace(c))
1615 continue;
1616 wasspace = isspace(c);
1617 if (wasspace)
1618 c = ' ';
1619 *cp++ = c;
1620 }
1621 while (buf < cp && isspace(cp[-1]))
1622 cp--;
1623 *cp++ = '\n';
1624 return cp - buf;
1625}
1626
dfefa935 1627int log_ref_setup(const char *refname, char *logfile, int bufsize)
6de08ae6 1628{
859c3017 1629 int logfd, oflags = O_APPEND | O_WRONLY;
9a13f0b7 1630
dfefa935 1631 git_snpath(logfile, bufsize, "logs/%s", refname);
4057deb5 1632 if (log_all_ref_updates &&
dfefa935
MH
1633 (!prefixcmp(refname, "refs/heads/") ||
1634 !prefixcmp(refname, "refs/remotes/") ||
1635 !prefixcmp(refname, "refs/notes/") ||
1636 !strcmp(refname, "HEAD"))) {
157aaea5 1637 if (safe_create_leading_directories(logfile) < 0)
6de08ae6 1638 return error("unable to create directory for %s",
157aaea5 1639 logfile);
6de08ae6
SP
1640 oflags |= O_CREAT;
1641 }
1642
157aaea5 1643 logfd = open(logfile, oflags, 0666);
6de08ae6 1644 if (logfd < 0) {
1974bf62 1645 if (!(oflags & O_CREAT) && errno == ENOENT)
6de08ae6 1646 return 0;
3b463c3f
JH
1647
1648 if ((oflags & O_CREAT) && errno == EISDIR) {
157aaea5 1649 if (remove_empty_directories(logfile)) {
3b463c3f 1650 return error("There are still logs under '%s'",
157aaea5 1651 logfile);
3b463c3f 1652 }
157aaea5 1653 logfd = open(logfile, oflags, 0666);
3b463c3f
JH
1654 }
1655
1656 if (logfd < 0)
1657 return error("Unable to append to %s: %s",
157aaea5 1658 logfile, strerror(errno));
6de08ae6
SP
1659 }
1660
157aaea5 1661 adjust_shared_perm(logfile);
859c3017
EM
1662 close(logfd);
1663 return 0;
1664}
443b92b6 1665
dfefa935 1666static int log_ref_write(const char *refname, const unsigned char *old_sha1,
859c3017
EM
1667 const unsigned char *new_sha1, const char *msg)
1668{
1669 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1670 unsigned maxlen, len;
1671 int msglen;
157aaea5 1672 char log_file[PATH_MAX];
859c3017
EM
1673 char *logrec;
1674 const char *committer;
1675
1676 if (log_all_ref_updates < 0)
1677 log_all_ref_updates = !is_bare_repository();
1678
dfefa935 1679 result = log_ref_setup(refname, log_file, sizeof(log_file));
859c3017
EM
1680 if (result)
1681 return result;
1682
1683 logfd = open(log_file, oflags);
1684 if (logfd < 0)
1685 return 0;
0ec29a47 1686 msglen = msg ? strlen(msg) : 0;
774751a8 1687 committer = git_committer_info(0);
8ac65937
JH
1688 maxlen = strlen(committer) + msglen + 100;
1689 logrec = xmalloc(maxlen);
1690 len = sprintf(logrec, "%s %s %s\n",
9a13f0b7
NP
1691 sha1_to_hex(old_sha1),
1692 sha1_to_hex(new_sha1),
8ac65937
JH
1693 committer);
1694 if (msglen)
0ec29a47 1695 len += copy_msg(logrec + len - 1, msg) - 1;
93822c22 1696 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
6de08ae6 1697 free(logrec);
91c8d590 1698 if (close(logfd) != 0 || written != len)
9a13f0b7 1699 return error("Unable to append to %s", log_file);
6de08ae6
SP
1700 return 0;
1701}
1702
c3b0dec5
LT
1703static int is_branch(const char *refname)
1704{
1705 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1706}
1707
4bd18c43
SP
1708int write_ref_sha1(struct ref_lock *lock,
1709 const unsigned char *sha1, const char *logmsg)
1710{
1711 static char term = '\n';
c3b0dec5 1712 struct object *o;
4bd18c43
SP
1713
1714 if (!lock)
95fc7512 1715 return -1;
a89fccd2 1716 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
4bd18c43
SP
1717 unlock_ref(lock);
1718 return 0;
95fc7512 1719 }
c3b0dec5
LT
1720 o = parse_object(sha1);
1721 if (!o) {
7be8b3ba 1722 error("Trying to write ref %s with nonexistent object %s",
c3b0dec5
LT
1723 lock->ref_name, sha1_to_hex(sha1));
1724 unlock_ref(lock);
1725 return -1;
1726 }
1727 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1728 error("Trying to write non-commit object %s to branch %s",
1729 sha1_to_hex(sha1), lock->ref_name);
1730 unlock_ref(lock);
1731 return -1;
1732 }
93822c22
AW
1733 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1734 write_in_full(lock->lock_fd, &term, 1) != 1
b531394d 1735 || close_ref(lock) < 0) {
c33d5174 1736 error("Couldn't write %s", lock->lk->filename);
4bd18c43
SP
1737 unlock_ref(lock);
1738 return -1;
1739 }
8bf90dc9 1740 clear_loose_ref_cache(get_ref_cache(NULL));
bd104db1
NP
1741 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1742 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1743 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
6de08ae6
SP
1744 unlock_ref(lock);
1745 return -1;
1746 }
605fac8b
NP
1747 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1748 /*
1749 * Special hack: If a branch is updated directly and HEAD
1750 * points to it (may happen on the remote side of a push
1751 * for example) then logically the HEAD reflog should be
1752 * updated too.
1753 * A generic solution implies reverse symref information,
1754 * but finding all symrefs pointing to the given branch
1755 * would be rather costly for this rare event (the direct
1756 * update of a branch) to be worth it. So let's cheat and
1757 * check with HEAD only which should cover 99% of all usage
1758 * scenarios (even 100% of the default ones).
1759 */
1760 unsigned char head_sha1[20];
1761 int head_flag;
1762 const char *head_ref;
8cad4744 1763 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
605fac8b
NP
1764 if (head_ref && (head_flag & REF_ISSYMREF) &&
1765 !strcmp(head_ref, lock->ref_name))
1766 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1767 }
b531394d 1768 if (commit_ref(lock)) {
434cd0cd 1769 error("Couldn't set %s", lock->ref_name);
4bd18c43
SP
1770 unlock_ref(lock);
1771 return -1;
1772 }
4bd18c43
SP
1773 unlock_ref(lock);
1774 return 0;
95fc7512 1775}
d556fae2 1776
8b5157e4
NP
1777int create_symref(const char *ref_target, const char *refs_heads_master,
1778 const char *logmsg)
41b625b0
NP
1779{
1780 const char *lockpath;
1781 char ref[1000];
1782 int fd, len, written;
a4f34cbb 1783 char *git_HEAD = git_pathdup("%s", ref_target);
8b5157e4
NP
1784 unsigned char old_sha1[20], new_sha1[20];
1785
1786 if (logmsg && read_ref(ref_target, old_sha1))
1787 hashclr(old_sha1);
41b625b0 1788
d48744d1
JH
1789 if (safe_create_leading_directories(git_HEAD) < 0)
1790 return error("unable to create directory for %s", git_HEAD);
1791
41b625b0
NP
1792#ifndef NO_SYMLINK_HEAD
1793 if (prefer_symlink_refs) {
1794 unlink(git_HEAD);
1795 if (!symlink(refs_heads_master, git_HEAD))
8b5157e4 1796 goto done;
41b625b0
NP
1797 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1798 }
1799#endif
1800
1801 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1802 if (sizeof(ref) <= len) {
1803 error("refname too long: %s", refs_heads_master);
47fc52e2 1804 goto error_free_return;
41b625b0
NP
1805 }
1806 lockpath = mkpath("%s.lock", git_HEAD);
1807 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1808 if (fd < 0) {
1809 error("Unable to open %s for writing", lockpath);
47fc52e2 1810 goto error_free_return;
41b625b0
NP
1811 }
1812 written = write_in_full(fd, ref, len);
91c8d590 1813 if (close(fd) != 0 || written != len) {
41b625b0 1814 error("Unable to write to %s", lockpath);
47fc52e2 1815 goto error_unlink_return;
41b625b0
NP
1816 }
1817 if (rename(lockpath, git_HEAD) < 0) {
41b625b0 1818 error("Unable to create %s", git_HEAD);
47fc52e2 1819 goto error_unlink_return;
41b625b0
NP
1820 }
1821 if (adjust_shared_perm(git_HEAD)) {
41b625b0 1822 error("Unable to fix permissions on %s", lockpath);
47fc52e2 1823 error_unlink_return:
691f1a28 1824 unlink_or_warn(lockpath);
47fc52e2
JH
1825 error_free_return:
1826 free(git_HEAD);
1827 return -1;
41b625b0 1828 }
8b5157e4 1829
ee96d11b 1830#ifndef NO_SYMLINK_HEAD
8b5157e4 1831 done:
ee96d11b 1832#endif
8b5157e4
NP
1833 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1834 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1835
47fc52e2 1836 free(git_HEAD);
41b625b0
NP
1837 return 0;
1838}
1839
16d7cc90
JH
1840static char *ref_msg(const char *line, const char *endp)
1841{
1842 const char *ep;
16d7cc90 1843 line += 82;
182af834
PH
1844 ep = memchr(line, '\n', endp - line);
1845 if (!ep)
1846 ep = endp;
1847 return xmemdupz(line, ep - line);
16d7cc90
JH
1848}
1849
dfefa935
MH
1850int read_ref_at(const char *refname, unsigned long at_time, int cnt,
1851 unsigned char *sha1, char **msg,
1852 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
d556fae2 1853{
e5229042 1854 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
d556fae2 1855 char *tz_c;
e29cb53a 1856 int logfd, tz, reccnt = 0;
d556fae2
SP
1857 struct stat st;
1858 unsigned long date;
e5229042 1859 unsigned char logged_sha1[20];
cb48cb58 1860 void *log_mapped;
dc49cd76 1861 size_t mapsz;
d556fae2 1862
dfefa935 1863 logfile = git_path("logs/%s", refname);
d556fae2
SP
1864 logfd = open(logfile, O_RDONLY, 0);
1865 if (logfd < 0)
d824cbba 1866 die_errno("Unable to read log '%s'", logfile);
d556fae2
SP
1867 fstat(logfd, &st);
1868 if (!st.st_size)
1869 die("Log %s is empty.", logfile);
dc49cd76
SP
1870 mapsz = xsize_t(st.st_size);
1871 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
cb48cb58 1872 logdata = log_mapped;
d556fae2
SP
1873 close(logfd);
1874
e5229042 1875 lastrec = NULL;
d556fae2
SP
1876 rec = logend = logdata + st.st_size;
1877 while (logdata < rec) {
e29cb53a 1878 reccnt++;
d556fae2
SP
1879 if (logdata < rec && *(rec-1) == '\n')
1880 rec--;
e5229042
SP
1881 lastgt = NULL;
1882 while (logdata < rec && *(rec-1) != '\n') {
d556fae2 1883 rec--;
e5229042
SP
1884 if (*rec == '>')
1885 lastgt = rec;
1886 }
1887 if (!lastgt)
d556fae2 1888 die("Log %s is corrupt.", logfile);
e5229042 1889 date = strtoul(lastgt + 1, &tz_c, 10);
ab2a1a32 1890 if (date <= at_time || cnt == 0) {
76a44c5c 1891 tz = strtoul(tz_c, NULL, 10);
16d7cc90
JH
1892 if (msg)
1893 *msg = ref_msg(rec, logend);
1894 if (cutoff_time)
1895 *cutoff_time = date;
1896 if (cutoff_tz)
1897 *cutoff_tz = tz;
1898 if (cutoff_cnt)
76a44c5c 1899 *cutoff_cnt = reccnt - 1;
e5229042
SP
1900 if (lastrec) {
1901 if (get_sha1_hex(lastrec, logged_sha1))
1902 die("Log %s is corrupt.", logfile);
1903 if (get_sha1_hex(rec + 41, sha1))
1904 die("Log %s is corrupt.", logfile);
a89fccd2 1905 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1906 warning("Log %s has gap after %s.",
73013afd 1907 logfile, show_date(date, tz, DATE_RFC2822));
e5229042 1908 }
e5f38ec3
JH
1909 }
1910 else if (date == at_time) {
e5229042
SP
1911 if (get_sha1_hex(rec + 41, sha1))
1912 die("Log %s is corrupt.", logfile);
e5f38ec3
JH
1913 }
1914 else {
e5229042
SP
1915 if (get_sha1_hex(rec + 41, logged_sha1))
1916 die("Log %s is corrupt.", logfile);
a89fccd2 1917 if (hashcmp(logged_sha1, sha1)) {
edbc25c5 1918 warning("Log %s unexpectedly ended on %s.",
73013afd 1919 logfile, show_date(date, tz, DATE_RFC2822));
e5229042
SP
1920 }
1921 }
dc49cd76 1922 munmap(log_mapped, mapsz);
d556fae2
SP
1923 return 0;
1924 }
e5229042 1925 lastrec = rec;
ab2a1a32
JH
1926 if (cnt > 0)
1927 cnt--;
d556fae2
SP
1928 }
1929
e5229042
SP
1930 rec = logdata;
1931 while (rec < logend && *rec != '>' && *rec != '\n')
1932 rec++;
1933 if (rec == logend || *rec == '\n')
d556fae2 1934 die("Log %s is corrupt.", logfile);
e5229042 1935 date = strtoul(rec + 1, &tz_c, 10);
d556fae2
SP
1936 tz = strtoul(tz_c, NULL, 10);
1937 if (get_sha1_hex(logdata, sha1))
1938 die("Log %s is corrupt.", logfile);
d1a4489a
JK
1939 if (is_null_sha1(sha1)) {
1940 if (get_sha1_hex(logdata + 41, sha1))
1941 die("Log %s is corrupt.", logfile);
1942 }
16d7cc90
JH
1943 if (msg)
1944 *msg = ref_msg(logdata, logend);
dc49cd76 1945 munmap(log_mapped, mapsz);
16d7cc90
JH
1946
1947 if (cutoff_time)
1948 *cutoff_time = date;
1949 if (cutoff_tz)
1950 *cutoff_tz = tz;
1951 if (cutoff_cnt)
1952 *cutoff_cnt = reccnt;
1953 return 1;
d556fae2 1954}
2ff81662 1955
dfefa935 1956int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2ff81662
JH
1957{
1958 const char *logfile;
1959 FILE *logfp;
8ca78803 1960 struct strbuf sb = STRBUF_INIT;
2266bf27 1961 int ret = 0;
2ff81662 1962
dfefa935 1963 logfile = git_path("logs/%s", refname);
2ff81662
JH
1964 logfp = fopen(logfile, "r");
1965 if (!logfp)
883d60fa 1966 return -1;
101d15e0
JH
1967
1968 if (ofs) {
1969 struct stat statbuf;
1970 if (fstat(fileno(logfp), &statbuf) ||
1971 statbuf.st_size < ofs ||
1972 fseek(logfp, -ofs, SEEK_END) ||
8ca78803 1973 strbuf_getwholeline(&sb, logfp, '\n')) {
9d33f7c2 1974 fclose(logfp);
8ca78803 1975 strbuf_release(&sb);
101d15e0 1976 return -1;
9d33f7c2 1977 }
101d15e0
JH
1978 }
1979
8ca78803 1980 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2ff81662 1981 unsigned char osha1[20], nsha1[20];
883d60fa
JS
1982 char *email_end, *message;
1983 unsigned long timestamp;
8ca78803 1984 int tz;
2ff81662
JH
1985
1986 /* old SP new SP name <email> SP time TAB msg LF */
8ca78803
RS
1987 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1988 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1989 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1990 !(email_end = strchr(sb.buf + 82, '>')) ||
883d60fa
JS
1991 email_end[1] != ' ' ||
1992 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1993 !message || message[0] != ' ' ||
1994 (message[1] != '+' && message[1] != '-') ||
1995 !isdigit(message[2]) || !isdigit(message[3]) ||
b4dd4856 1996 !isdigit(message[4]) || !isdigit(message[5]))
2ff81662 1997 continue; /* corrupt? */
883d60fa
JS
1998 email_end[1] = '\0';
1999 tz = strtol(message + 1, NULL, 10);
b4dd4856
JS
2000 if (message[6] != '\t')
2001 message += 6;
2002 else
2003 message += 7;
8ca78803
RS
2004 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2005 cb_data);
883d60fa 2006 if (ret)
2266bf27 2007 break;
2ff81662
JH
2008 }
2009 fclose(logfp);
8ca78803 2010 strbuf_release(&sb);
2266bf27 2011 return ret;
2ff81662 2012}
e29cb53a 2013
dfefa935 2014int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
101d15e0 2015{
dfefa935 2016 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
101d15e0
JH
2017}
2018
eb8381c8
NP
2019static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
2020{
2021 DIR *dir = opendir(git_path("logs/%s", base));
fcee5a14 2022 int retval = 0;
eb8381c8
NP
2023
2024 if (dir) {
2025 struct dirent *de;
2026 int baselen = strlen(base);
2027 char *log = xmalloc(baselen + 257);
2028
2029 memcpy(log, base, baselen);
2030 if (baselen && base[baselen-1] != '/')
2031 log[baselen++] = '/';
2032
2033 while ((de = readdir(dir)) != NULL) {
2034 struct stat st;
2035 int namelen;
2036
2037 if (de->d_name[0] == '.')
2038 continue;
2039 namelen = strlen(de->d_name);
2040 if (namelen > 255)
2041 continue;
2042 if (has_extension(de->d_name, ".lock"))
2043 continue;
2044 memcpy(log + baselen, de->d_name, namelen+1);
2045 if (stat(git_path("logs/%s", log), &st) < 0)
2046 continue;
2047 if (S_ISDIR(st.st_mode)) {
2048 retval = do_for_each_reflog(log, fn, cb_data);
2049 } else {
2050 unsigned char sha1[20];
c6893323 2051 if (read_ref_full(log, sha1, 0, NULL))
eb8381c8
NP
2052 retval = error("bad ref for %s", log);
2053 else
2054 retval = fn(log, sha1, 0, cb_data);
2055 }
2056 if (retval)
2057 break;
2058 }
2059 free(log);
2060 closedir(dir);
2061 }
acb39f64 2062 else if (*base)
fcee5a14 2063 return errno;
eb8381c8
NP
2064 return retval;
2065}
2066
2067int for_each_reflog(each_ref_fn fn, void *cb_data)
2068{
2069 return do_for_each_reflog("", fn, cb_data);
2070}
3d9f037c
CR
2071
2072int update_ref(const char *action, const char *refname,
2073 const unsigned char *sha1, const unsigned char *oldval,
2074 int flags, enum action_on_err onerr)
2075{
2076 static struct ref_lock *lock;
2077 lock = lock_any_ref_for_update(refname, oldval, flags);
2078 if (!lock) {
2079 const char *str = "Cannot lock the ref '%s'.";
2080 switch (onerr) {
2081 case MSG_ON_ERR: error(str, refname); break;
2082 case DIE_ON_ERR: die(str, refname); break;
2083 case QUIET_ON_ERR: break;
2084 }
2085 return 1;
2086 }
2087 if (write_ref_sha1(lock, sha1, action) < 0) {
2088 const char *str = "Cannot update the ref '%s'.";
2089 switch (onerr) {
2090 case MSG_ON_ERR: error(str, refname); break;
2091 case DIE_ON_ERR: die(str, refname); break;
2092 case QUIET_ON_ERR: break;
2093 }
2094 return 1;
2095 }
2096 return 0;
2097}
cda69f48 2098
5483f799 2099struct ref *find_ref_by_name(const struct ref *list, const char *name)
cda69f48
JK
2100{
2101 for ( ; list; list = list->next)
2102 if (!strcmp(list->name, name))
5483f799 2103 return (struct ref *)list;
cda69f48
JK
2104 return NULL;
2105}
7c2b3029
JK
2106
2107/*
2108 * generate a format suitable for scanf from a ref_rev_parse_rules
2109 * rule, that is replace the "%.*s" spec with a "%s" spec
2110 */
2111static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2112{
2113 char *spec;
2114
2115 spec = strstr(rule, "%.*s");
2116 if (!spec || strstr(spec + 4, "%.*s"))
2117 die("invalid rule in ref_rev_parse_rules: %s", rule);
2118
2119 /* copy all until spec */
2120 strncpy(scanf_fmt, rule, spec - rule);
2121 scanf_fmt[spec - rule] = '\0';
2122 /* copy new spec */
2123 strcat(scanf_fmt, "%s");
2124 /* copy remaining rule */
2125 strcat(scanf_fmt, spec + 4);
2126
2127 return;
2128}
2129
dfefa935 2130char *shorten_unambiguous_ref(const char *refname, int strict)
7c2b3029
JK
2131{
2132 int i;
2133 static char **scanf_fmts;
2134 static int nr_rules;
2135 char *short_name;
2136
2137 /* pre generate scanf formats from ref_rev_parse_rules[] */
2138 if (!nr_rules) {
2139 size_t total_len = 0;
2140
2141 /* the rule list is NULL terminated, count them first */
2142 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2143 /* no +1 because strlen("%s") < strlen("%.*s") */
2144 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2145
2146 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2147
2148 total_len = 0;
2149 for (i = 0; i < nr_rules; i++) {
2150 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2151 + total_len;
2152 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2153 total_len += strlen(ref_rev_parse_rules[i]);
2154 }
2155 }
2156
2157 /* bail out if there are no rules */
2158 if (!nr_rules)
dfefa935 2159 return xstrdup(refname);
7c2b3029 2160
dfefa935
MH
2161 /* buffer for scanf result, at most refname must fit */
2162 short_name = xstrdup(refname);
7c2b3029
JK
2163
2164 /* skip first rule, it will always match */
2165 for (i = nr_rules - 1; i > 0 ; --i) {
2166 int j;
6e7b3309 2167 int rules_to_fail = i;
7c2b3029
JK
2168 int short_name_len;
2169
dfefa935 2170 if (1 != sscanf(refname, scanf_fmts[i], short_name))
7c2b3029
JK
2171 continue;
2172
2173 short_name_len = strlen(short_name);
2174
6e7b3309
BW
2175 /*
2176 * in strict mode, all (except the matched one) rules
2177 * must fail to resolve to a valid non-ambiguous ref
2178 */
2179 if (strict)
2180 rules_to_fail = nr_rules;
2181
7c2b3029
JK
2182 /*
2183 * check if the short name resolves to a valid ref,
2184 * but use only rules prior to the matched one
2185 */
6e7b3309 2186 for (j = 0; j < rules_to_fail; j++) {
7c2b3029 2187 const char *rule = ref_rev_parse_rules[j];
7c2b3029
JK
2188 char refname[PATH_MAX];
2189
6e7b3309
BW
2190 /* skip matched rule */
2191 if (i == j)
2192 continue;
2193
7c2b3029
JK
2194 /*
2195 * the short name is ambiguous, if it resolves
2196 * (with this previous rule) to a valid ref
2197 * read_ref() returns 0 on success
2198 */
2199 mksnpath(refname, sizeof(refname),
2200 rule, short_name_len, short_name);
c6893323 2201 if (ref_exists(refname))
7c2b3029
JK
2202 break;
2203 }
2204
2205 /*
2206 * short name is non-ambiguous if all previous rules
2207 * haven't resolved to a valid ref
2208 */
6e7b3309 2209 if (j == rules_to_fail)
7c2b3029
JK
2210 return short_name;
2211 }
2212
2213 free(short_name);
dfefa935 2214 return xstrdup(refname);
7c2b3029 2215}