sha1-name.c: remove implicit dependency on the_index
[git/git.git] / sha1-name.c
1 #include "cache.h"
2 #include "config.h"
3 #include "tag.h"
4 #include "commit.h"
5 #include "tree.h"
6 #include "blob.h"
7 #include "tree-walk.h"
8 #include "refs.h"
9 #include "remote.h"
10 #include "dir.h"
11 #include "sha1-array.h"
12 #include "packfile.h"
13 #include "object-store.h"
14 #include "repository.h"
15 #include "midx.h"
16 #include "commit-reach.h"
17
18 static int get_oid_oneline(const char *, struct object_id *, struct commit_list *);
19
20 typedef int (*disambiguate_hint_fn)(const struct object_id *, void *);
21
22 struct disambiguate_state {
23 int len; /* length of prefix in hex chars */
24 char hex_pfx[GIT_MAX_HEXSZ + 1];
25 struct object_id bin_pfx;
26
27 disambiguate_hint_fn fn;
28 void *cb_data;
29 struct object_id candidate;
30 unsigned candidate_exists:1;
31 unsigned candidate_checked:1;
32 unsigned candidate_ok:1;
33 unsigned disambiguate_fn_used:1;
34 unsigned ambiguous:1;
35 unsigned always_call_fn:1;
36 };
37
38 static void update_candidates(struct disambiguate_state *ds, const struct object_id *current)
39 {
40 if (ds->always_call_fn) {
41 ds->ambiguous = ds->fn(current, ds->cb_data) ? 1 : 0;
42 return;
43 }
44 if (!ds->candidate_exists) {
45 /* this is the first candidate */
46 oidcpy(&ds->candidate, current);
47 ds->candidate_exists = 1;
48 return;
49 } else if (oideq(&ds->candidate, current)) {
50 /* the same as what we already have seen */
51 return;
52 }
53
54 if (!ds->fn) {
55 /* cannot disambiguate between ds->candidate and current */
56 ds->ambiguous = 1;
57 return;
58 }
59
60 if (!ds->candidate_checked) {
61 ds->candidate_ok = ds->fn(&ds->candidate, ds->cb_data);
62 ds->disambiguate_fn_used = 1;
63 ds->candidate_checked = 1;
64 }
65
66 if (!ds->candidate_ok) {
67 /* discard the candidate; we know it does not satisfy fn */
68 oidcpy(&ds->candidate, current);
69 ds->candidate_checked = 0;
70 return;
71 }
72
73 /* if we reach this point, we know ds->candidate satisfies fn */
74 if (ds->fn(current, ds->cb_data)) {
75 /*
76 * if both current and candidate satisfy fn, we cannot
77 * disambiguate.
78 */
79 ds->candidate_ok = 0;
80 ds->ambiguous = 1;
81 }
82
83 /* otherwise, current can be discarded and candidate is still good */
84 }
85
86 static int match_sha(unsigned, const unsigned char *, const unsigned char *);
87
88 static void find_short_object_filename(struct disambiguate_state *ds)
89 {
90 int subdir_nr = ds->bin_pfx.hash[0];
91 struct object_directory *odb;
92
93 for (odb = the_repository->objects->odb;
94 odb && !ds->ambiguous;
95 odb = odb->next) {
96 int pos;
97
98 odb_load_loose_cache(odb, subdir_nr);
99 pos = oid_array_lookup(&odb->loose_objects_cache, &ds->bin_pfx);
100 if (pos < 0)
101 pos = -1 - pos;
102 while (!ds->ambiguous && pos < odb->loose_objects_cache.nr) {
103 const struct object_id *oid;
104 oid = odb->loose_objects_cache.oid + pos;
105 if (!match_sha(ds->len, ds->bin_pfx.hash, oid->hash))
106 break;
107 update_candidates(ds, oid);
108 pos++;
109 }
110 }
111 }
112
113 static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
114 {
115 do {
116 if (*a != *b)
117 return 0;
118 a++;
119 b++;
120 len -= 2;
121 } while (len > 1);
122 if (len)
123 if ((*a ^ *b) & 0xf0)
124 return 0;
125 return 1;
126 }
127
128 static void unique_in_midx(struct multi_pack_index *m,
129 struct disambiguate_state *ds)
130 {
131 uint32_t num, i, first = 0;
132 const struct object_id *current = NULL;
133 num = m->num_objects;
134
135 if (!num)
136 return;
137
138 bsearch_midx(&ds->bin_pfx, m, &first);
139
140 /*
141 * At this point, "first" is the location of the lowest object
142 * with an object name that could match "bin_pfx". See if we have
143 * 0, 1 or more objects that actually match(es).
144 */
145 for (i = first; i < num && !ds->ambiguous; i++) {
146 struct object_id oid;
147 current = nth_midxed_object_oid(&oid, m, i);
148 if (!match_sha(ds->len, ds->bin_pfx.hash, current->hash))
149 break;
150 update_candidates(ds, current);
151 }
152 }
153
154 static void unique_in_pack(struct packed_git *p,
155 struct disambiguate_state *ds)
156 {
157 uint32_t num, i, first = 0;
158 const struct object_id *current = NULL;
159
160 if (open_pack_index(p) || !p->num_objects)
161 return;
162
163 num = p->num_objects;
164 bsearch_pack(&ds->bin_pfx, p, &first);
165
166 /*
167 * At this point, "first" is the location of the lowest object
168 * with an object name that could match "bin_pfx". See if we have
169 * 0, 1 or more objects that actually match(es).
170 */
171 for (i = first; i < num && !ds->ambiguous; i++) {
172 struct object_id oid;
173 current = nth_packed_object_oid(&oid, p, i);
174 if (!match_sha(ds->len, ds->bin_pfx.hash, current->hash))
175 break;
176 update_candidates(ds, current);
177 }
178 }
179
180 static void find_short_packed_object(struct disambiguate_state *ds)
181 {
182 struct multi_pack_index *m;
183 struct packed_git *p;
184
185 for (m = get_multi_pack_index(the_repository); m && !ds->ambiguous;
186 m = m->next)
187 unique_in_midx(m, ds);
188 for (p = get_packed_git(the_repository); p && !ds->ambiguous;
189 p = p->next)
190 unique_in_pack(p, ds);
191 }
192
193 #define SHORT_NAME_NOT_FOUND (-1)
194 #define SHORT_NAME_AMBIGUOUS (-2)
195
196 static int finish_object_disambiguation(struct disambiguate_state *ds,
197 struct object_id *oid)
198 {
199 if (ds->ambiguous)
200 return SHORT_NAME_AMBIGUOUS;
201
202 if (!ds->candidate_exists)
203 return SHORT_NAME_NOT_FOUND;
204
205 if (!ds->candidate_checked)
206 /*
207 * If this is the only candidate, there is no point
208 * calling the disambiguation hint callback.
209 *
210 * On the other hand, if the current candidate
211 * replaced an earlier candidate that did _not_ pass
212 * the disambiguation hint callback, then we do have
213 * more than one objects that match the short name
214 * given, so we should make sure this one matches;
215 * otherwise, if we discovered this one and the one
216 * that we previously discarded in the reverse order,
217 * we would end up showing different results in the
218 * same repository!
219 */
220 ds->candidate_ok = (!ds->disambiguate_fn_used ||
221 ds->fn(&ds->candidate, ds->cb_data));
222
223 if (!ds->candidate_ok)
224 return SHORT_NAME_AMBIGUOUS;
225
226 oidcpy(oid, &ds->candidate);
227 return 0;
228 }
229
230 static int disambiguate_commit_only(const struct object_id *oid, void *cb_data_unused)
231 {
232 int kind = oid_object_info(the_repository, oid, NULL);
233 return kind == OBJ_COMMIT;
234 }
235
236 static int disambiguate_committish_only(const struct object_id *oid, void *cb_data_unused)
237 {
238 struct object *obj;
239 int kind;
240
241 kind = oid_object_info(the_repository, oid, NULL);
242 if (kind == OBJ_COMMIT)
243 return 1;
244 if (kind != OBJ_TAG)
245 return 0;
246
247 /* We need to do this the hard way... */
248 obj = deref_tag(the_repository, parse_object(the_repository, oid),
249 NULL, 0);
250 if (obj && obj->type == OBJ_COMMIT)
251 return 1;
252 return 0;
253 }
254
255 static int disambiguate_tree_only(const struct object_id *oid, void *cb_data_unused)
256 {
257 int kind = oid_object_info(the_repository, oid, NULL);
258 return kind == OBJ_TREE;
259 }
260
261 static int disambiguate_treeish_only(const struct object_id *oid, void *cb_data_unused)
262 {
263 struct object *obj;
264 int kind;
265
266 kind = oid_object_info(the_repository, oid, NULL);
267 if (kind == OBJ_TREE || kind == OBJ_COMMIT)
268 return 1;
269 if (kind != OBJ_TAG)
270 return 0;
271
272 /* We need to do this the hard way... */
273 obj = deref_tag(the_repository, parse_object(the_repository, oid),
274 NULL, 0);
275 if (obj && (obj->type == OBJ_TREE || obj->type == OBJ_COMMIT))
276 return 1;
277 return 0;
278 }
279
280 static int disambiguate_blob_only(const struct object_id *oid, void *cb_data_unused)
281 {
282 int kind = oid_object_info(the_repository, oid, NULL);
283 return kind == OBJ_BLOB;
284 }
285
286 static disambiguate_hint_fn default_disambiguate_hint;
287
288 int set_disambiguate_hint_config(const char *var, const char *value)
289 {
290 static const struct {
291 const char *name;
292 disambiguate_hint_fn fn;
293 } hints[] = {
294 { "none", NULL },
295 { "commit", disambiguate_commit_only },
296 { "committish", disambiguate_committish_only },
297 { "tree", disambiguate_tree_only },
298 { "treeish", disambiguate_treeish_only },
299 { "blob", disambiguate_blob_only }
300 };
301 int i;
302
303 if (!value)
304 return config_error_nonbool(var);
305
306 for (i = 0; i < ARRAY_SIZE(hints); i++) {
307 if (!strcasecmp(value, hints[i].name)) {
308 default_disambiguate_hint = hints[i].fn;
309 return 0;
310 }
311 }
312
313 return error("unknown hint type for '%s': %s", var, value);
314 }
315
316 static int init_object_disambiguation(const char *name, int len,
317 struct disambiguate_state *ds)
318 {
319 int i;
320
321 if (len < MINIMUM_ABBREV || len > the_hash_algo->hexsz)
322 return -1;
323
324 memset(ds, 0, sizeof(*ds));
325
326 for (i = 0; i < len ;i++) {
327 unsigned char c = name[i];
328 unsigned char val;
329 if (c >= '0' && c <= '9')
330 val = c - '0';
331 else if (c >= 'a' && c <= 'f')
332 val = c - 'a' + 10;
333 else if (c >= 'A' && c <='F') {
334 val = c - 'A' + 10;
335 c -= 'A' - 'a';
336 }
337 else
338 return -1;
339 ds->hex_pfx[i] = c;
340 if (!(i & 1))
341 val <<= 4;
342 ds->bin_pfx.hash[i >> 1] |= val;
343 }
344
345 ds->len = len;
346 ds->hex_pfx[len] = '\0';
347 prepare_alt_odb(the_repository);
348 return 0;
349 }
350
351 static int show_ambiguous_object(const struct object_id *oid, void *data)
352 {
353 const struct disambiguate_state *ds = data;
354 struct strbuf desc = STRBUF_INIT;
355 int type;
356
357 if (ds->fn && !ds->fn(oid, ds->cb_data))
358 return 0;
359
360 type = oid_object_info(the_repository, oid, NULL);
361 if (type == OBJ_COMMIT) {
362 struct commit *commit = lookup_commit(the_repository, oid);
363 if (commit) {
364 struct pretty_print_context pp = {0};
365 pp.date_mode.type = DATE_SHORT;
366 format_commit_message(commit, " %ad - %s", &desc, &pp);
367 }
368 } else if (type == OBJ_TAG) {
369 struct tag *tag = lookup_tag(the_repository, oid);
370 if (!parse_tag(tag) && tag->tag)
371 strbuf_addf(&desc, " %s", tag->tag);
372 }
373
374 advise(" %s %s%s",
375 find_unique_abbrev(oid, DEFAULT_ABBREV),
376 type_name(type) ? type_name(type) : "unknown type",
377 desc.buf);
378
379 strbuf_release(&desc);
380 return 0;
381 }
382
383 static int collect_ambiguous(const struct object_id *oid, void *data)
384 {
385 oid_array_append(data, oid);
386 return 0;
387 }
388
389 static int sort_ambiguous(const void *a, const void *b)
390 {
391 int a_type = oid_object_info(the_repository, a, NULL);
392 int b_type = oid_object_info(the_repository, b, NULL);
393 int a_type_sort;
394 int b_type_sort;
395
396 /*
397 * Sorts by hash within the same object type, just as
398 * oid_array_for_each_unique() would do.
399 */
400 if (a_type == b_type)
401 return oidcmp(a, b);
402
403 /*
404 * Between object types show tags, then commits, and finally
405 * trees and blobs.
406 *
407 * The object_type enum is commit, tree, blob, tag, but we
408 * want tag, commit, tree blob. Cleverly (perhaps too
409 * cleverly) do that with modulus, since the enum assigns 1 to
410 * commit, so tag becomes 0.
411 */
412 a_type_sort = a_type % 4;
413 b_type_sort = b_type % 4;
414 return a_type_sort > b_type_sort ? 1 : -1;
415 }
416
417 static int get_short_oid(const char *name, int len, struct object_id *oid,
418 unsigned flags)
419 {
420 int status;
421 struct disambiguate_state ds;
422 int quietly = !!(flags & GET_OID_QUIETLY);
423
424 if (init_object_disambiguation(name, len, &ds) < 0)
425 return -1;
426
427 if (HAS_MULTI_BITS(flags & GET_OID_DISAMBIGUATORS))
428 BUG("multiple get_short_oid disambiguator flags");
429
430 if (flags & GET_OID_COMMIT)
431 ds.fn = disambiguate_commit_only;
432 else if (flags & GET_OID_COMMITTISH)
433 ds.fn = disambiguate_committish_only;
434 else if (flags & GET_OID_TREE)
435 ds.fn = disambiguate_tree_only;
436 else if (flags & GET_OID_TREEISH)
437 ds.fn = disambiguate_treeish_only;
438 else if (flags & GET_OID_BLOB)
439 ds.fn = disambiguate_blob_only;
440 else
441 ds.fn = default_disambiguate_hint;
442
443 find_short_object_filename(&ds);
444 find_short_packed_object(&ds);
445 status = finish_object_disambiguation(&ds, oid);
446
447 if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) {
448 struct oid_array collect = OID_ARRAY_INIT;
449
450 error(_("short SHA1 %s is ambiguous"), ds.hex_pfx);
451
452 /*
453 * We may still have ambiguity if we simply saw a series of
454 * candidates that did not satisfy our hint function. In
455 * that case, we still want to show them, so disable the hint
456 * function entirely.
457 */
458 if (!ds.ambiguous)
459 ds.fn = NULL;
460
461 advise(_("The candidates are:"));
462 for_each_abbrev(ds.hex_pfx, collect_ambiguous, &collect);
463 QSORT(collect.oid, collect.nr, sort_ambiguous);
464
465 if (oid_array_for_each(&collect, show_ambiguous_object, &ds))
466 BUG("show_ambiguous_object shouldn't return non-zero");
467 oid_array_clear(&collect);
468 }
469
470 return status;
471 }
472
473 int for_each_abbrev(const char *prefix, each_abbrev_fn fn, void *cb_data)
474 {
475 struct oid_array collect = OID_ARRAY_INIT;
476 struct disambiguate_state ds;
477 int ret;
478
479 if (init_object_disambiguation(prefix, strlen(prefix), &ds) < 0)
480 return -1;
481
482 ds.always_call_fn = 1;
483 ds.fn = collect_ambiguous;
484 ds.cb_data = &collect;
485 find_short_object_filename(&ds);
486 find_short_packed_object(&ds);
487
488 ret = oid_array_for_each_unique(&collect, fn, cb_data);
489 oid_array_clear(&collect);
490 return ret;
491 }
492
493 /*
494 * Return the slot of the most-significant bit set in "val". There are various
495 * ways to do this quickly with fls() or __builtin_clzl(), but speed is
496 * probably not a big deal here.
497 */
498 static unsigned msb(unsigned long val)
499 {
500 unsigned r = 0;
501 while (val >>= 1)
502 r++;
503 return r;
504 }
505
506 struct min_abbrev_data {
507 unsigned int init_len;
508 unsigned int cur_len;
509 char *hex;
510 const struct object_id *oid;
511 };
512
513 static inline char get_hex_char_from_oid(const struct object_id *oid,
514 unsigned int pos)
515 {
516 static const char hex[] = "0123456789abcdef";
517
518 if ((pos & 1) == 0)
519 return hex[oid->hash[pos >> 1] >> 4];
520 else
521 return hex[oid->hash[pos >> 1] & 0xf];
522 }
523
524 static int extend_abbrev_len(const struct object_id *oid, void *cb_data)
525 {
526 struct min_abbrev_data *mad = cb_data;
527
528 unsigned int i = mad->init_len;
529 while (mad->hex[i] && mad->hex[i] == get_hex_char_from_oid(oid, i))
530 i++;
531
532 if (i < GIT_MAX_RAWSZ && i >= mad->cur_len)
533 mad->cur_len = i + 1;
534
535 return 0;
536 }
537
538 static void find_abbrev_len_for_midx(struct multi_pack_index *m,
539 struct min_abbrev_data *mad)
540 {
541 int match = 0;
542 uint32_t num, first = 0;
543 struct object_id oid;
544 const struct object_id *mad_oid;
545
546 if (!m->num_objects)
547 return;
548
549 num = m->num_objects;
550 mad_oid = mad->oid;
551 match = bsearch_midx(mad_oid, m, &first);
552
553 /*
554 * first is now the position in the packfile where we would insert
555 * mad->hash if it does not exist (or the position of mad->hash if
556 * it does exist). Hence, we consider a maximum of two objects
557 * nearby for the abbreviation length.
558 */
559 mad->init_len = 0;
560 if (!match) {
561 if (nth_midxed_object_oid(&oid, m, first))
562 extend_abbrev_len(&oid, mad);
563 } else if (first < num - 1) {
564 if (nth_midxed_object_oid(&oid, m, first + 1))
565 extend_abbrev_len(&oid, mad);
566 }
567 if (first > 0) {
568 if (nth_midxed_object_oid(&oid, m, first - 1))
569 extend_abbrev_len(&oid, mad);
570 }
571 mad->init_len = mad->cur_len;
572 }
573
574 static void find_abbrev_len_for_pack(struct packed_git *p,
575 struct min_abbrev_data *mad)
576 {
577 int match = 0;
578 uint32_t num, first = 0;
579 struct object_id oid;
580 const struct object_id *mad_oid;
581
582 if (open_pack_index(p) || !p->num_objects)
583 return;
584
585 num = p->num_objects;
586 mad_oid = mad->oid;
587 match = bsearch_pack(mad_oid, p, &first);
588
589 /*
590 * first is now the position in the packfile where we would insert
591 * mad->hash if it does not exist (or the position of mad->hash if
592 * it does exist). Hence, we consider a maximum of two objects
593 * nearby for the abbreviation length.
594 */
595 mad->init_len = 0;
596 if (!match) {
597 if (nth_packed_object_oid(&oid, p, first))
598 extend_abbrev_len(&oid, mad);
599 } else if (first < num - 1) {
600 if (nth_packed_object_oid(&oid, p, first + 1))
601 extend_abbrev_len(&oid, mad);
602 }
603 if (first > 0) {
604 if (nth_packed_object_oid(&oid, p, first - 1))
605 extend_abbrev_len(&oid, mad);
606 }
607 mad->init_len = mad->cur_len;
608 }
609
610 static void find_abbrev_len_packed(struct min_abbrev_data *mad)
611 {
612 struct multi_pack_index *m;
613 struct packed_git *p;
614
615 for (m = get_multi_pack_index(the_repository); m; m = m->next)
616 find_abbrev_len_for_midx(m, mad);
617 for (p = get_packed_git(the_repository); p; p = p->next)
618 find_abbrev_len_for_pack(p, mad);
619 }
620
621 int find_unique_abbrev_r(char *hex, const struct object_id *oid, int len)
622 {
623 struct disambiguate_state ds;
624 struct min_abbrev_data mad;
625 struct object_id oid_ret;
626 const unsigned hexsz = the_hash_algo->hexsz;
627
628 if (len < 0) {
629 unsigned long count = approximate_object_count();
630 /*
631 * Add one because the MSB only tells us the highest bit set,
632 * not including the value of all the _other_ bits (so "15"
633 * is only one off of 2^4, but the MSB is the 3rd bit.
634 */
635 len = msb(count) + 1;
636 /*
637 * We now know we have on the order of 2^len objects, which
638 * expects a collision at 2^(len/2). But we also care about hex
639 * chars, not bits, and there are 4 bits per hex. So all
640 * together we need to divide by 2 and round up.
641 */
642 len = DIV_ROUND_UP(len, 2);
643 /*
644 * For very small repos, we stick with our regular fallback.
645 */
646 if (len < FALLBACK_DEFAULT_ABBREV)
647 len = FALLBACK_DEFAULT_ABBREV;
648 }
649
650 oid_to_hex_r(hex, oid);
651 if (len == hexsz || !len)
652 return hexsz;
653
654 mad.init_len = len;
655 mad.cur_len = len;
656 mad.hex = hex;
657 mad.oid = oid;
658
659 find_abbrev_len_packed(&mad);
660
661 if (init_object_disambiguation(hex, mad.cur_len, &ds) < 0)
662 return -1;
663
664 ds.fn = extend_abbrev_len;
665 ds.always_call_fn = 1;
666 ds.cb_data = (void *)&mad;
667
668 find_short_object_filename(&ds);
669 (void)finish_object_disambiguation(&ds, &oid_ret);
670
671 hex[mad.cur_len] = 0;
672 return mad.cur_len;
673 }
674
675 const char *find_unique_abbrev(const struct object_id *oid, int len)
676 {
677 static int bufno;
678 static char hexbuffer[4][GIT_MAX_HEXSZ + 1];
679 char *hex = hexbuffer[bufno];
680 bufno = (bufno + 1) % ARRAY_SIZE(hexbuffer);
681 find_unique_abbrev_r(hex, oid, len);
682 return hex;
683 }
684
685 static int ambiguous_path(const char *path, int len)
686 {
687 int slash = 1;
688 int cnt;
689
690 for (cnt = 0; cnt < len; cnt++) {
691 switch (*path++) {
692 case '\0':
693 break;
694 case '/':
695 if (slash)
696 break;
697 slash = 1;
698 continue;
699 case '.':
700 continue;
701 default:
702 slash = 0;
703 continue;
704 }
705 break;
706 }
707 return slash;
708 }
709
710 static inline int at_mark(const char *string, int len,
711 const char **suffix, int nr)
712 {
713 int i;
714
715 for (i = 0; i < nr; i++) {
716 int suffix_len = strlen(suffix[i]);
717 if (suffix_len <= len
718 && !strncasecmp(string, suffix[i], suffix_len))
719 return suffix_len;
720 }
721 return 0;
722 }
723
724 static inline int upstream_mark(const char *string, int len)
725 {
726 const char *suffix[] = { "@{upstream}", "@{u}" };
727 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
728 }
729
730 static inline int push_mark(const char *string, int len)
731 {
732 const char *suffix[] = { "@{push}" };
733 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
734 }
735
736 static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags);
737 static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
738
739 static int get_oid_basic(const char *str, int len, struct object_id *oid,
740 unsigned int flags)
741 {
742 static const char *warn_msg = "refname '%.*s' is ambiguous.";
743 static const char *object_name_msg = N_(
744 "Git normally never creates a ref that ends with 40 hex characters\n"
745 "because it will be ignored when you just specify 40-hex. These refs\n"
746 "may be created by mistake. For example,\n"
747 "\n"
748 " git checkout -b $br $(git rev-parse ...)\n"
749 "\n"
750 "where \"$br\" is somehow empty and a 40-hex ref is created. Please\n"
751 "examine these refs and maybe delete them. Turn this message off by\n"
752 "running \"git config advice.objectNameWarning false\"");
753 struct object_id tmp_oid;
754 char *real_ref = NULL;
755 int refs_found = 0;
756 int at, reflog_len, nth_prior = 0;
757
758 if (len == the_hash_algo->hexsz && !get_oid_hex(str, oid)) {
759 if (warn_ambiguous_refs && warn_on_object_refname_ambiguity) {
760 refs_found = dwim_ref(str, len, &tmp_oid, &real_ref);
761 if (refs_found > 0) {
762 warning(warn_msg, len, str);
763 if (advice_object_name_warning)
764 fprintf(stderr, "%s\n", _(object_name_msg));
765 }
766 free(real_ref);
767 }
768 return 0;
769 }
770
771 /* basic@{time or number or -number} format to query ref-log */
772 reflog_len = at = 0;
773 if (len && str[len-1] == '}') {
774 for (at = len-4; at >= 0; at--) {
775 if (str[at] == '@' && str[at+1] == '{') {
776 if (str[at+2] == '-') {
777 if (at != 0)
778 /* @{-N} not at start */
779 return -1;
780 nth_prior = 1;
781 continue;
782 }
783 if (!upstream_mark(str + at, len - at) &&
784 !push_mark(str + at, len - at)) {
785 reflog_len = (len-1) - (at+2);
786 len = at;
787 }
788 break;
789 }
790 }
791 }
792
793 /* Accept only unambiguous ref paths. */
794 if (len && ambiguous_path(str, len))
795 return -1;
796
797 if (nth_prior) {
798 struct strbuf buf = STRBUF_INIT;
799 int detached;
800
801 if (interpret_nth_prior_checkout(str, len, &buf) > 0) {
802 detached = (buf.len == the_hash_algo->hexsz && !get_oid_hex(buf.buf, oid));
803 strbuf_release(&buf);
804 if (detached)
805 return 0;
806 }
807 }
808
809 if (!len && reflog_len)
810 /* allow "@{...}" to mean the current branch reflog */
811 refs_found = dwim_ref("HEAD", 4, oid, &real_ref);
812 else if (reflog_len)
813 refs_found = dwim_log(str, len, oid, &real_ref);
814 else
815 refs_found = dwim_ref(str, len, oid, &real_ref);
816
817 if (!refs_found)
818 return -1;
819
820 if (warn_ambiguous_refs && !(flags & GET_OID_QUIETLY) &&
821 (refs_found > 1 ||
822 !get_short_oid(str, len, &tmp_oid, GET_OID_QUIETLY)))
823 warning(warn_msg, len, str);
824
825 if (reflog_len) {
826 int nth, i;
827 timestamp_t at_time;
828 timestamp_t co_time;
829 int co_tz, co_cnt;
830
831 /* Is it asking for N-th entry, or approxidate? */
832 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
833 char ch = str[at+2+i];
834 if ('0' <= ch && ch <= '9')
835 nth = nth * 10 + ch - '0';
836 else
837 nth = -1;
838 }
839 if (100000000 <= nth) {
840 at_time = nth;
841 nth = -1;
842 } else if (0 <= nth)
843 at_time = 0;
844 else {
845 int errors = 0;
846 char *tmp = xstrndup(str + at + 2, reflog_len);
847 at_time = approxidate_careful(tmp, &errors);
848 free(tmp);
849 if (errors) {
850 free(real_ref);
851 return -1;
852 }
853 }
854 if (read_ref_at(real_ref, flags, at_time, nth, oid, NULL,
855 &co_time, &co_tz, &co_cnt)) {
856 if (!len) {
857 if (starts_with(real_ref, "refs/heads/")) {
858 str = real_ref + 11;
859 len = strlen(real_ref + 11);
860 } else {
861 /* detached HEAD */
862 str = "HEAD";
863 len = 4;
864 }
865 }
866 if (at_time) {
867 if (!(flags & GET_OID_QUIETLY)) {
868 warning("Log for '%.*s' only goes "
869 "back to %s.", len, str,
870 show_date(co_time, co_tz, DATE_MODE(RFC2822)));
871 }
872 } else {
873 if (flags & GET_OID_QUIETLY) {
874 exit(128);
875 }
876 die("Log for '%.*s' only has %d entries.",
877 len, str, co_cnt);
878 }
879 }
880 }
881
882 free(real_ref);
883 return 0;
884 }
885
886 static int get_parent(const char *name, int len,
887 struct object_id *result, int idx)
888 {
889 struct object_id oid;
890 int ret = get_oid_1(name, len, &oid, GET_OID_COMMITTISH);
891 struct commit *commit;
892 struct commit_list *p;
893
894 if (ret)
895 return ret;
896 commit = lookup_commit_reference(the_repository, &oid);
897 if (parse_commit(commit))
898 return -1;
899 if (!idx) {
900 oidcpy(result, &commit->object.oid);
901 return 0;
902 }
903 p = commit->parents;
904 while (p) {
905 if (!--idx) {
906 oidcpy(result, &p->item->object.oid);
907 return 0;
908 }
909 p = p->next;
910 }
911 return -1;
912 }
913
914 static int get_nth_ancestor(const char *name, int len,
915 struct object_id *result, int generation)
916 {
917 struct object_id oid;
918 struct commit *commit;
919 int ret;
920
921 ret = get_oid_1(name, len, &oid, GET_OID_COMMITTISH);
922 if (ret)
923 return ret;
924 commit = lookup_commit_reference(the_repository, &oid);
925 if (!commit)
926 return -1;
927
928 while (generation--) {
929 if (parse_commit(commit) || !commit->parents)
930 return -1;
931 commit = commit->parents->item;
932 }
933 oidcpy(result, &commit->object.oid);
934 return 0;
935 }
936
937 struct object *peel_to_type(const char *name, int namelen,
938 struct object *o, enum object_type expected_type)
939 {
940 if (name && !namelen)
941 namelen = strlen(name);
942 while (1) {
943 if (!o || (!o->parsed && !parse_object(the_repository, &o->oid)))
944 return NULL;
945 if (expected_type == OBJ_ANY || o->type == expected_type)
946 return o;
947 if (o->type == OBJ_TAG)
948 o = ((struct tag*) o)->tagged;
949 else if (o->type == OBJ_COMMIT)
950 o = &(get_commit_tree(((struct commit *)o))->object);
951 else {
952 if (name)
953 error("%.*s: expected %s type, but the object "
954 "dereferences to %s type",
955 namelen, name, type_name(expected_type),
956 type_name(o->type));
957 return NULL;
958 }
959 }
960 }
961
962 static int peel_onion(const char *name, int len, struct object_id *oid,
963 unsigned lookup_flags)
964 {
965 struct object_id outer;
966 const char *sp;
967 unsigned int expected_type = 0;
968 struct object *o;
969
970 /*
971 * "ref^{type}" dereferences ref repeatedly until you cannot
972 * dereference anymore, or you get an object of given type,
973 * whichever comes first. "ref^{}" means just dereference
974 * tags until you get a non-tag. "ref^0" is a shorthand for
975 * "ref^{commit}". "commit^{tree}" could be used to find the
976 * top-level tree of the given commit.
977 */
978 if (len < 4 || name[len-1] != '}')
979 return -1;
980
981 for (sp = name + len - 1; name <= sp; sp--) {
982 int ch = *sp;
983 if (ch == '{' && name < sp && sp[-1] == '^')
984 break;
985 }
986 if (sp <= name)
987 return -1;
988
989 sp++; /* beginning of type name, or closing brace for empty */
990 if (starts_with(sp, "commit}"))
991 expected_type = OBJ_COMMIT;
992 else if (starts_with(sp, "tag}"))
993 expected_type = OBJ_TAG;
994 else if (starts_with(sp, "tree}"))
995 expected_type = OBJ_TREE;
996 else if (starts_with(sp, "blob}"))
997 expected_type = OBJ_BLOB;
998 else if (starts_with(sp, "object}"))
999 expected_type = OBJ_ANY;
1000 else if (sp[0] == '}')
1001 expected_type = OBJ_NONE;
1002 else if (sp[0] == '/')
1003 expected_type = OBJ_COMMIT;
1004 else
1005 return -1;
1006
1007 lookup_flags &= ~GET_OID_DISAMBIGUATORS;
1008 if (expected_type == OBJ_COMMIT)
1009 lookup_flags |= GET_OID_COMMITTISH;
1010 else if (expected_type == OBJ_TREE)
1011 lookup_flags |= GET_OID_TREEISH;
1012
1013 if (get_oid_1(name, sp - name - 2, &outer, lookup_flags))
1014 return -1;
1015
1016 o = parse_object(the_repository, &outer);
1017 if (!o)
1018 return -1;
1019 if (!expected_type) {
1020 o = deref_tag(the_repository, o, name, sp - name - 2);
1021 if (!o || (!o->parsed && !parse_object(the_repository, &o->oid)))
1022 return -1;
1023 oidcpy(oid, &o->oid);
1024 return 0;
1025 }
1026
1027 /*
1028 * At this point, the syntax look correct, so
1029 * if we do not get the needed object, we should
1030 * barf.
1031 */
1032 o = peel_to_type(name, len, o, expected_type);
1033 if (!o)
1034 return -1;
1035
1036 oidcpy(oid, &o->oid);
1037 if (sp[0] == '/') {
1038 /* "$commit^{/foo}" */
1039 char *prefix;
1040 int ret;
1041 struct commit_list *list = NULL;
1042
1043 /*
1044 * $commit^{/}. Some regex implementation may reject.
1045 * We don't need regex anyway. '' pattern always matches.
1046 */
1047 if (sp[1] == '}')
1048 return 0;
1049
1050 prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
1051 commit_list_insert((struct commit *)o, &list);
1052 ret = get_oid_oneline(prefix, oid, list);
1053 free(prefix);
1054 return ret;
1055 }
1056 return 0;
1057 }
1058
1059 static int get_describe_name(const char *name, int len, struct object_id *oid)
1060 {
1061 const char *cp;
1062 unsigned flags = GET_OID_QUIETLY | GET_OID_COMMIT;
1063
1064 for (cp = name + len - 1; name + 2 <= cp; cp--) {
1065 char ch = *cp;
1066 if (!isxdigit(ch)) {
1067 /* We must be looking at g in "SOMETHING-g"
1068 * for it to be describe output.
1069 */
1070 if (ch == 'g' && cp[-1] == '-') {
1071 cp++;
1072 len -= cp - name;
1073 return get_short_oid(cp, len, oid, flags);
1074 }
1075 }
1076 }
1077 return -1;
1078 }
1079
1080 static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags)
1081 {
1082 int ret, has_suffix;
1083 const char *cp;
1084
1085 /*
1086 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
1087 */
1088 has_suffix = 0;
1089 for (cp = name + len - 1; name <= cp; cp--) {
1090 int ch = *cp;
1091 if ('0' <= ch && ch <= '9')
1092 continue;
1093 if (ch == '~' || ch == '^')
1094 has_suffix = ch;
1095 break;
1096 }
1097
1098 if (has_suffix) {
1099 int num = 0;
1100 int len1 = cp - name;
1101 cp++;
1102 while (cp < name + len)
1103 num = num * 10 + *cp++ - '0';
1104 if (!num && len1 == len - 1)
1105 num = 1;
1106 if (has_suffix == '^')
1107 return get_parent(name, len1, oid, num);
1108 /* else if (has_suffix == '~') -- goes without saying */
1109 return get_nth_ancestor(name, len1, oid, num);
1110 }
1111
1112 ret = peel_onion(name, len, oid, lookup_flags);
1113 if (!ret)
1114 return 0;
1115
1116 ret = get_oid_basic(name, len, oid, lookup_flags);
1117 if (!ret)
1118 return 0;
1119
1120 /* It could be describe output that is "SOMETHING-gXXXX" */
1121 ret = get_describe_name(name, len, oid);
1122 if (!ret)
1123 return 0;
1124
1125 return get_short_oid(name, len, oid, lookup_flags);
1126 }
1127
1128 /*
1129 * This interprets names like ':/Initial revision of "git"' by searching
1130 * through history and returning the first commit whose message starts
1131 * the given regular expression.
1132 *
1133 * For negative-matching, prefix the pattern-part with '!-', like: ':/!-WIP'.
1134 *
1135 * For a literal '!' character at the beginning of a pattern, you have to repeat
1136 * that, like: ':/!!foo'
1137 *
1138 * For future extension, all other sequences beginning with ':/!' are reserved.
1139 */
1140
1141 /* Remember to update object flag allocation in object.h */
1142 #define ONELINE_SEEN (1u<<20)
1143
1144 static int handle_one_ref(const char *path, const struct object_id *oid,
1145 int flag, void *cb_data)
1146 {
1147 struct commit_list **list = cb_data;
1148 struct object *object = parse_object(the_repository, oid);
1149 if (!object)
1150 return 0;
1151 if (object->type == OBJ_TAG) {
1152 object = deref_tag(the_repository, object, path,
1153 strlen(path));
1154 if (!object)
1155 return 0;
1156 }
1157 if (object->type != OBJ_COMMIT)
1158 return 0;
1159 commit_list_insert((struct commit *)object, list);
1160 return 0;
1161 }
1162
1163 static int get_oid_oneline(const char *prefix, struct object_id *oid,
1164 struct commit_list *list)
1165 {
1166 struct commit_list *backup = NULL, *l;
1167 int found = 0;
1168 int negative = 0;
1169 regex_t regex;
1170
1171 if (prefix[0] == '!') {
1172 prefix++;
1173
1174 if (prefix[0] == '-') {
1175 prefix++;
1176 negative = 1;
1177 } else if (prefix[0] != '!') {
1178 return -1;
1179 }
1180 }
1181
1182 if (regcomp(&regex, prefix, REG_EXTENDED))
1183 return -1;
1184
1185 for (l = list; l; l = l->next) {
1186 l->item->object.flags |= ONELINE_SEEN;
1187 commit_list_insert(l->item, &backup);
1188 }
1189 while (list) {
1190 const char *p, *buf;
1191 struct commit *commit;
1192 int matches;
1193
1194 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
1195 if (!parse_object(the_repository, &commit->object.oid))
1196 continue;
1197 buf = get_commit_buffer(commit, NULL);
1198 p = strstr(buf, "\n\n");
1199 matches = negative ^ (p && !regexec(&regex, p + 2, 0, NULL, 0));
1200 unuse_commit_buffer(commit, buf);
1201
1202 if (matches) {
1203 oidcpy(oid, &commit->object.oid);
1204 found = 1;
1205 break;
1206 }
1207 }
1208 regfree(&regex);
1209 free_commit_list(list);
1210 for (l = backup; l; l = l->next)
1211 clear_commit_marks(l->item, ONELINE_SEEN);
1212 free_commit_list(backup);
1213 return found ? 0 : -1;
1214 }
1215
1216 struct grab_nth_branch_switch_cbdata {
1217 int remaining;
1218 struct strbuf buf;
1219 };
1220
1221 static int grab_nth_branch_switch(struct object_id *ooid, struct object_id *noid,
1222 const char *email, timestamp_t timestamp, int tz,
1223 const char *message, void *cb_data)
1224 {
1225 struct grab_nth_branch_switch_cbdata *cb = cb_data;
1226 const char *match = NULL, *target = NULL;
1227 size_t len;
1228
1229 if (skip_prefix(message, "checkout: moving from ", &match))
1230 target = strstr(match, " to ");
1231
1232 if (!match || !target)
1233 return 0;
1234 if (--(cb->remaining) == 0) {
1235 len = target - match;
1236 strbuf_reset(&cb->buf);
1237 strbuf_add(&cb->buf, match, len);
1238 return 1; /* we are done */
1239 }
1240 return 0;
1241 }
1242
1243 /*
1244 * Parse @{-N} syntax, return the number of characters parsed
1245 * if successful; otherwise signal an error with negative value.
1246 */
1247 static int interpret_nth_prior_checkout(const char *name, int namelen,
1248 struct strbuf *buf)
1249 {
1250 long nth;
1251 int retval;
1252 struct grab_nth_branch_switch_cbdata cb;
1253 const char *brace;
1254 char *num_end;
1255
1256 if (namelen < 4)
1257 return -1;
1258 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
1259 return -1;
1260 brace = memchr(name, '}', namelen);
1261 if (!brace)
1262 return -1;
1263 nth = strtol(name + 3, &num_end, 10);
1264 if (num_end != brace)
1265 return -1;
1266 if (nth <= 0)
1267 return -1;
1268 cb.remaining = nth;
1269 strbuf_init(&cb.buf, 20);
1270
1271 retval = 0;
1272 if (0 < for_each_reflog_ent_reverse("HEAD", grab_nth_branch_switch, &cb)) {
1273 strbuf_reset(buf);
1274 strbuf_addbuf(buf, &cb.buf);
1275 retval = brace - name + 1;
1276 }
1277
1278 strbuf_release(&cb.buf);
1279 return retval;
1280 }
1281
1282 int get_oid_mb(const char *name, struct object_id *oid)
1283 {
1284 struct commit *one, *two;
1285 struct commit_list *mbs;
1286 struct object_id oid_tmp;
1287 const char *dots;
1288 int st;
1289
1290 dots = strstr(name, "...");
1291 if (!dots)
1292 return get_oid(name, oid);
1293 if (dots == name)
1294 st = get_oid("HEAD", &oid_tmp);
1295 else {
1296 struct strbuf sb;
1297 strbuf_init(&sb, dots - name);
1298 strbuf_add(&sb, name, dots - name);
1299 st = get_oid_committish(sb.buf, &oid_tmp);
1300 strbuf_release(&sb);
1301 }
1302 if (st)
1303 return st;
1304 one = lookup_commit_reference_gently(the_repository, &oid_tmp, 0);
1305 if (!one)
1306 return -1;
1307
1308 if (get_oid_committish(dots[3] ? (dots + 3) : "HEAD", &oid_tmp))
1309 return -1;
1310 two = lookup_commit_reference_gently(the_repository, &oid_tmp, 0);
1311 if (!two)
1312 return -1;
1313 mbs = get_merge_bases(one, two);
1314 if (!mbs || mbs->next)
1315 st = -1;
1316 else {
1317 st = 0;
1318 oidcpy(oid, &mbs->item->object.oid);
1319 }
1320 free_commit_list(mbs);
1321 return st;
1322 }
1323
1324 /* parse @something syntax, when 'something' is not {.*} */
1325 static int interpret_empty_at(const char *name, int namelen, int len, struct strbuf *buf)
1326 {
1327 const char *next;
1328
1329 if (len || name[1] == '{')
1330 return -1;
1331
1332 /* make sure it's a single @, or @@{.*}, not @foo */
1333 next = memchr(name + len + 1, '@', namelen - len - 1);
1334 if (next && next[1] != '{')
1335 return -1;
1336 if (!next)
1337 next = name + namelen;
1338 if (next != name + 1)
1339 return -1;
1340
1341 strbuf_reset(buf);
1342 strbuf_add(buf, "HEAD", 4);
1343 return 1;
1344 }
1345
1346 static int reinterpret(const char *name, int namelen, int len,
1347 struct strbuf *buf, unsigned allowed)
1348 {
1349 /* we have extra data, which might need further processing */
1350 struct strbuf tmp = STRBUF_INIT;
1351 int used = buf->len;
1352 int ret;
1353
1354 strbuf_add(buf, name + len, namelen - len);
1355 ret = interpret_branch_name(buf->buf, buf->len, &tmp, allowed);
1356 /* that data was not interpreted, remove our cruft */
1357 if (ret < 0) {
1358 strbuf_setlen(buf, used);
1359 return len;
1360 }
1361 strbuf_reset(buf);
1362 strbuf_addbuf(buf, &tmp);
1363 strbuf_release(&tmp);
1364 /* tweak for size of {-N} versus expanded ref name */
1365 return ret - used + len;
1366 }
1367
1368 static void set_shortened_ref(struct strbuf *buf, const char *ref)
1369 {
1370 char *s = shorten_unambiguous_ref(ref, 0);
1371 strbuf_reset(buf);
1372 strbuf_addstr(buf, s);
1373 free(s);
1374 }
1375
1376 static int branch_interpret_allowed(const char *refname, unsigned allowed)
1377 {
1378 if (!allowed)
1379 return 1;
1380
1381 if ((allowed & INTERPRET_BRANCH_LOCAL) &&
1382 starts_with(refname, "refs/heads/"))
1383 return 1;
1384 if ((allowed & INTERPRET_BRANCH_REMOTE) &&
1385 starts_with(refname, "refs/remotes/"))
1386 return 1;
1387
1388 return 0;
1389 }
1390
1391 static int interpret_branch_mark(const char *name, int namelen,
1392 int at, struct strbuf *buf,
1393 int (*get_mark)(const char *, int),
1394 const char *(*get_data)(struct branch *,
1395 struct strbuf *),
1396 unsigned allowed)
1397 {
1398 int len;
1399 struct branch *branch;
1400 struct strbuf err = STRBUF_INIT;
1401 const char *value;
1402
1403 len = get_mark(name + at, namelen - at);
1404 if (!len)
1405 return -1;
1406
1407 if (memchr(name, ':', at))
1408 return -1;
1409
1410 if (at) {
1411 char *name_str = xmemdupz(name, at);
1412 branch = branch_get(name_str);
1413 free(name_str);
1414 } else
1415 branch = branch_get(NULL);
1416
1417 value = get_data(branch, &err);
1418 if (!value)
1419 die("%s", err.buf);
1420
1421 if (!branch_interpret_allowed(value, allowed))
1422 return -1;
1423
1424 set_shortened_ref(buf, value);
1425 return len + at;
1426 }
1427
1428 int interpret_branch_name(const char *name, int namelen, struct strbuf *buf,
1429 unsigned allowed)
1430 {
1431 char *at;
1432 const char *start;
1433 int len;
1434
1435 if (!namelen)
1436 namelen = strlen(name);
1437
1438 if (!allowed || (allowed & INTERPRET_BRANCH_LOCAL)) {
1439 len = interpret_nth_prior_checkout(name, namelen, buf);
1440 if (!len) {
1441 return len; /* syntax Ok, not enough switches */
1442 } else if (len > 0) {
1443 if (len == namelen)
1444 return len; /* consumed all */
1445 else
1446 return reinterpret(name, namelen, len, buf, allowed);
1447 }
1448 }
1449
1450 for (start = name;
1451 (at = memchr(start, '@', namelen - (start - name)));
1452 start = at + 1) {
1453
1454 if (!allowed || (allowed & INTERPRET_BRANCH_HEAD)) {
1455 len = interpret_empty_at(name, namelen, at - name, buf);
1456 if (len > 0)
1457 return reinterpret(name, namelen, len, buf,
1458 allowed);
1459 }
1460
1461 len = interpret_branch_mark(name, namelen, at - name, buf,
1462 upstream_mark, branch_get_upstream,
1463 allowed);
1464 if (len > 0)
1465 return len;
1466
1467 len = interpret_branch_mark(name, namelen, at - name, buf,
1468 push_mark, branch_get_push,
1469 allowed);
1470 if (len > 0)
1471 return len;
1472 }
1473
1474 return -1;
1475 }
1476
1477 void strbuf_branchname(struct strbuf *sb, const char *name, unsigned allowed)
1478 {
1479 int len = strlen(name);
1480 int used = interpret_branch_name(name, len, sb, allowed);
1481
1482 if (used < 0)
1483 used = 0;
1484 strbuf_add(sb, name + used, len - used);
1485 }
1486
1487 int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
1488 {
1489 if (startup_info->have_repository)
1490 strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
1491 else
1492 strbuf_addstr(sb, name);
1493
1494 /*
1495 * This splice must be done even if we end up rejecting the
1496 * name; builtin/branch.c::copy_or_rename_branch() still wants
1497 * to see what the name expanded to so that "branch -m" can be
1498 * used as a tool to correct earlier mistakes.
1499 */
1500 strbuf_splice(sb, 0, 0, "refs/heads/", 11);
1501
1502 if (*name == '-' ||
1503 !strcmp(sb->buf, "refs/heads/HEAD"))
1504 return -1;
1505
1506 return check_refname_format(sb->buf, 0);
1507 }
1508
1509 /*
1510 * This is like "get_oid_basic()", except it allows "object ID expressions",
1511 * notably "xyz^" for "parent of xyz"
1512 */
1513 int get_oid(const char *name, struct object_id *oid)
1514 {
1515 struct object_context unused;
1516 return get_oid_with_context(the_repository, name, 0, oid, &unused);
1517 }
1518
1519
1520 /*
1521 * Many callers know that the user meant to name a commit-ish by
1522 * syntactical positions where the object name appears. Calling this
1523 * function allows the machinery to disambiguate shorter-than-unique
1524 * abbreviated object names between commit-ish and others.
1525 *
1526 * Note that this does NOT error out when the named object is not a
1527 * commit-ish. It is merely to give a hint to the disambiguation
1528 * machinery.
1529 */
1530 int get_oid_committish(const char *name, struct object_id *oid)
1531 {
1532 struct object_context unused;
1533 return get_oid_with_context(the_repository,
1534 name, GET_OID_COMMITTISH,
1535 oid, &unused);
1536 }
1537
1538 int get_oid_treeish(const char *name, struct object_id *oid)
1539 {
1540 struct object_context unused;
1541 return get_oid_with_context(the_repository,
1542 name, GET_OID_TREEISH,
1543 oid, &unused);
1544 }
1545
1546 int get_oid_commit(const char *name, struct object_id *oid)
1547 {
1548 struct object_context unused;
1549 return get_oid_with_context(the_repository,
1550 name, GET_OID_COMMIT,
1551 oid, &unused);
1552 }
1553
1554 int get_oid_tree(const char *name, struct object_id *oid)
1555 {
1556 struct object_context unused;
1557 return get_oid_with_context(the_repository,
1558 name, GET_OID_TREE,
1559 oid, &unused);
1560 }
1561
1562 int get_oid_blob(const char *name, struct object_id *oid)
1563 {
1564 struct object_context unused;
1565 return get_oid_with_context(the_repository,
1566 name, GET_OID_BLOB,
1567 oid, &unused);
1568 }
1569
1570 /* Must be called only when object_name:filename doesn't exist. */
1571 static void diagnose_invalid_oid_path(const char *prefix,
1572 const char *filename,
1573 const struct object_id *tree_oid,
1574 const char *object_name,
1575 int object_name_len)
1576 {
1577 struct object_id oid;
1578 unsigned mode;
1579
1580 if (!prefix)
1581 prefix = "";
1582
1583 if (file_exists(filename))
1584 die("Path '%s' exists on disk, but not in '%.*s'.",
1585 filename, object_name_len, object_name);
1586 if (is_missing_file_error(errno)) {
1587 char *fullname = xstrfmt("%s%s", prefix, filename);
1588
1589 if (!get_tree_entry(tree_oid, fullname, &oid, &mode)) {
1590 die("Path '%s' exists, but not '%s'.\n"
1591 "Did you mean '%.*s:%s' aka '%.*s:./%s'?",
1592 fullname,
1593 filename,
1594 object_name_len, object_name,
1595 fullname,
1596 object_name_len, object_name,
1597 filename);
1598 }
1599 die("Path '%s' does not exist in '%.*s'",
1600 filename, object_name_len, object_name);
1601 }
1602 }
1603
1604 /* Must be called only when :stage:filename doesn't exist. */
1605 static void diagnose_invalid_index_path(struct index_state *istate,
1606 int stage,
1607 const char *prefix,
1608 const char *filename)
1609 {
1610 const struct cache_entry *ce;
1611 int pos;
1612 unsigned namelen = strlen(filename);
1613 struct strbuf fullname = STRBUF_INIT;
1614
1615 if (!prefix)
1616 prefix = "";
1617
1618 /* Wrong stage number? */
1619 pos = index_name_pos(istate, filename, namelen);
1620 if (pos < 0)
1621 pos = -pos - 1;
1622 if (pos < istate->cache_nr) {
1623 ce = istate->cache[pos];
1624 if (ce_namelen(ce) == namelen &&
1625 !memcmp(ce->name, filename, namelen))
1626 die("Path '%s' is in the index, but not at stage %d.\n"
1627 "Did you mean ':%d:%s'?",
1628 filename, stage,
1629 ce_stage(ce), filename);
1630 }
1631
1632 /* Confusion between relative and absolute filenames? */
1633 strbuf_addstr(&fullname, prefix);
1634 strbuf_addstr(&fullname, filename);
1635 pos = index_name_pos(istate, fullname.buf, fullname.len);
1636 if (pos < 0)
1637 pos = -pos - 1;
1638 if (pos < istate->cache_nr) {
1639 ce = istate->cache[pos];
1640 if (ce_namelen(ce) == fullname.len &&
1641 !memcmp(ce->name, fullname.buf, fullname.len))
1642 die("Path '%s' is in the index, but not '%s'.\n"
1643 "Did you mean ':%d:%s' aka ':%d:./%s'?",
1644 fullname.buf, filename,
1645 ce_stage(ce), fullname.buf,
1646 ce_stage(ce), filename);
1647 }
1648
1649 if (file_exists(filename))
1650 die("Path '%s' exists on disk, but not in the index.", filename);
1651 if (is_missing_file_error(errno))
1652 die("Path '%s' does not exist (neither on disk nor in the index).",
1653 filename);
1654
1655 strbuf_release(&fullname);
1656 }
1657
1658
1659 static char *resolve_relative_path(const char *rel)
1660 {
1661 if (!starts_with(rel, "./") && !starts_with(rel, "../"))
1662 return NULL;
1663
1664 if (!is_inside_work_tree())
1665 die("relative path syntax can't be used outside working tree.");
1666
1667 /* die() inside prefix_path() if resolved path is outside worktree */
1668 return prefix_path(startup_info->prefix,
1669 startup_info->prefix ? strlen(startup_info->prefix) : 0,
1670 rel);
1671 }
1672
1673 static int get_oid_with_context_1(struct repository *repo,
1674 const char *name,
1675 unsigned flags,
1676 const char *prefix,
1677 struct object_id *oid,
1678 struct object_context *oc)
1679 {
1680 int ret, bracket_depth;
1681 int namelen = strlen(name);
1682 const char *cp;
1683 int only_to_die = flags & GET_OID_ONLY_TO_DIE;
1684
1685 if (only_to_die)
1686 flags |= GET_OID_QUIETLY;
1687
1688 memset(oc, 0, sizeof(*oc));
1689 oc->mode = S_IFINVALID;
1690 strbuf_init(&oc->symlink_path, 0);
1691 ret = get_oid_1(name, namelen, oid, flags);
1692 if (!ret)
1693 return ret;
1694 /*
1695 * sha1:path --> object name of path in ent sha1
1696 * :path -> object name of absolute path in index
1697 * :./path -> object name of path relative to cwd in index
1698 * :[0-3]:path -> object name of path in index at stage
1699 * :/foo -> recent commit matching foo
1700 */
1701 if (name[0] == ':') {
1702 int stage = 0;
1703 const struct cache_entry *ce;
1704 char *new_path = NULL;
1705 int pos;
1706 if (!only_to_die && namelen > 2 && name[1] == '/') {
1707 struct commit_list *list = NULL;
1708
1709 for_each_ref(handle_one_ref, &list);
1710 head_ref(handle_one_ref, &list);
1711 commit_list_sort_by_date(&list);
1712 return get_oid_oneline(name + 2, oid, list);
1713 }
1714 if (namelen < 3 ||
1715 name[2] != ':' ||
1716 name[1] < '0' || '3' < name[1])
1717 cp = name + 1;
1718 else {
1719 stage = name[1] - '0';
1720 cp = name + 3;
1721 }
1722 new_path = resolve_relative_path(cp);
1723 if (!new_path) {
1724 namelen = namelen - (cp - name);
1725 } else {
1726 cp = new_path;
1727 namelen = strlen(cp);
1728 }
1729
1730 if (flags & GET_OID_RECORD_PATH)
1731 oc->path = xstrdup(cp);
1732
1733 if (!repo->index->cache)
1734 repo_read_index(the_repository);
1735 pos = index_name_pos(repo->index, cp, namelen);
1736 if (pos < 0)
1737 pos = -pos - 1;
1738 while (pos < repo->index->cache_nr) {
1739 ce = repo->index->cache[pos];
1740 if (ce_namelen(ce) != namelen ||
1741 memcmp(ce->name, cp, namelen))
1742 break;
1743 if (ce_stage(ce) == stage) {
1744 oidcpy(oid, &ce->oid);
1745 oc->mode = ce->ce_mode;
1746 free(new_path);
1747 return 0;
1748 }
1749 pos++;
1750 }
1751 if (only_to_die && name[1] && name[1] != '/')
1752 diagnose_invalid_index_path(repo->index, stage, prefix, cp);
1753 free(new_path);
1754 return -1;
1755 }
1756 for (cp = name, bracket_depth = 0; *cp; cp++) {
1757 if (*cp == '{')
1758 bracket_depth++;
1759 else if (bracket_depth && *cp == '}')
1760 bracket_depth--;
1761 else if (!bracket_depth && *cp == ':')
1762 break;
1763 }
1764 if (*cp == ':') {
1765 struct object_id tree_oid;
1766 int len = cp - name;
1767 unsigned sub_flags = flags;
1768
1769 sub_flags &= ~GET_OID_DISAMBIGUATORS;
1770 sub_flags |= GET_OID_TREEISH;
1771
1772 if (!get_oid_1(name, len, &tree_oid, sub_flags)) {
1773 const char *filename = cp+1;
1774 char *new_filename = NULL;
1775
1776 new_filename = resolve_relative_path(filename);
1777 if (new_filename)
1778 filename = new_filename;
1779 if (flags & GET_OID_FOLLOW_SYMLINKS) {
1780 ret = get_tree_entry_follow_symlinks(&tree_oid,
1781 filename, oid, &oc->symlink_path,
1782 &oc->mode);
1783 } else {
1784 ret = get_tree_entry(&tree_oid, filename, oid,
1785 &oc->mode);
1786 if (ret && only_to_die) {
1787 diagnose_invalid_oid_path(prefix,
1788 filename,
1789 &tree_oid,
1790 name, len);
1791 }
1792 }
1793 if (flags & GET_OID_RECORD_PATH)
1794 oc->path = xstrdup(filename);
1795
1796 free(new_filename);
1797 return ret;
1798 } else {
1799 if (only_to_die)
1800 die("Invalid object name '%.*s'.", len, name);
1801 }
1802 }
1803 return ret;
1804 }
1805
1806 /*
1807 * Call this function when you know "name" given by the end user must
1808 * name an object but it doesn't; the function _may_ die with a better
1809 * diagnostic message than "no such object 'name'", e.g. "Path 'doc' does not
1810 * exist in 'HEAD'" when given "HEAD:doc", or it may return in which case
1811 * you have a chance to diagnose the error further.
1812 */
1813 void maybe_die_on_misspelt_object_name(const char *name, const char *prefix)
1814 {
1815 struct object_context oc;
1816 struct object_id oid;
1817 get_oid_with_context_1(the_repository, name, GET_OID_ONLY_TO_DIE,
1818 prefix, &oid, &oc);
1819 }
1820
1821 int get_oid_with_context(struct repository *repo, const char *str,
1822 unsigned flags, struct object_id *oid,
1823 struct object_context *oc)
1824 {
1825 if (flags & GET_OID_FOLLOW_SYMLINKS && flags & GET_OID_ONLY_TO_DIE)
1826 BUG("incompatible flags for get_sha1_with_context");
1827 return get_oid_with_context_1(repo, str, flags, NULL, oid, oc);
1828 }