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