pack-bitmap.h: remove magic number
[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 "submodule.h"
16 #include "midx.h"
17 #include "commit-reach.h"
18
19 static int get_oid_oneline(struct repository *r, const char *, struct object_id *, struct commit_list *);
20
21 typedef int (*disambiguate_hint_fn)(struct repository *, const struct object_id *, void *);
22
23 struct disambiguate_state {
24 int len; /* length of prefix in hex chars */
25 char hex_pfx[GIT_MAX_HEXSZ + 1];
26 struct object_id bin_pfx;
27
28 struct repository *repo;
29 disambiguate_hint_fn fn;
30 void *cb_data;
31 struct object_id candidate;
32 unsigned candidate_exists:1;
33 unsigned candidate_checked:1;
34 unsigned candidate_ok:1;
35 unsigned disambiguate_fn_used:1;
36 unsigned ambiguous:1;
37 unsigned always_call_fn:1;
38 };
39
40 static void update_candidates(struct disambiguate_state *ds, const struct object_id *current)
41 {
42 if (ds->always_call_fn) {
43 ds->ambiguous = ds->fn(ds->repo, current, ds->cb_data) ? 1 : 0;
44 return;
45 }
46 if (!ds->candidate_exists) {
47 /* this is the first candidate */
48 oidcpy(&ds->candidate, current);
49 ds->candidate_exists = 1;
50 return;
51 } else if (oideq(&ds->candidate, current)) {
52 /* the same as what we already have seen */
53 return;
54 }
55
56 if (!ds->fn) {
57 /* cannot disambiguate between ds->candidate and current */
58 ds->ambiguous = 1;
59 return;
60 }
61
62 if (!ds->candidate_checked) {
63 ds->candidate_ok = ds->fn(ds->repo, &ds->candidate, ds->cb_data);
64 ds->disambiguate_fn_used = 1;
65 ds->candidate_checked = 1;
66 }
67
68 if (!ds->candidate_ok) {
69 /* discard the candidate; we know it does not satisfy fn */
70 oidcpy(&ds->candidate, current);
71 ds->candidate_checked = 0;
72 return;
73 }
74
75 /* if we reach this point, we know ds->candidate satisfies fn */
76 if (ds->fn(ds->repo, current, ds->cb_data)) {
77 /*
78 * if both current and candidate satisfy fn, we cannot
79 * disambiguate.
80 */
81 ds->candidate_ok = 0;
82 ds->ambiguous = 1;
83 }
84
85 /* otherwise, current can be discarded and candidate is still good */
86 }
87
88 static int match_sha(unsigned, const unsigned char *, const unsigned char *);
89
90 static void find_short_object_filename(struct disambiguate_state *ds)
91 {
92 struct object_directory *odb;
93
94 for (odb = ds->repo->objects->odb; odb && !ds->ambiguous; odb = odb->next) {
95 int pos;
96 struct oid_array *loose_objects;
97
98 loose_objects = odb_loose_cache(odb, &ds->bin_pfx);
99 pos = oid_array_lookup(loose_objects, &ds->bin_pfx);
100 if (pos < 0)
101 pos = -1 - pos;
102 while (!ds->ambiguous && pos < loose_objects->nr) {
103 const struct object_id *oid;
104 oid = loose_objects->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 (p->multi_pack_index)
161 return;
162
163 if (open_pack_index(p) || !p->num_objects)
164 return;
165
166 num = p->num_objects;
167 bsearch_pack(&ds->bin_pfx, p, &first);
168
169 /*
170 * At this point, "first" is the location of the lowest object
171 * with an object name that could match "bin_pfx". See if we have
172 * 0, 1 or more objects that actually match(es).
173 */
174 for (i = first; i < num && !ds->ambiguous; i++) {
175 struct object_id oid;
176 current = nth_packed_object_oid(&oid, p, i);
177 if (!match_sha(ds->len, ds->bin_pfx.hash, current->hash))
178 break;
179 update_candidates(ds, current);
180 }
181 }
182
183 static void find_short_packed_object(struct disambiguate_state *ds)
184 {
185 struct multi_pack_index *m;
186 struct packed_git *p;
187
188 for (m = get_multi_pack_index(ds->repo); m && !ds->ambiguous;
189 m = m->next)
190 unique_in_midx(m, ds);
191 for (p = get_packed_git(ds->repo); p && !ds->ambiguous;
192 p = p->next)
193 unique_in_pack(p, ds);
194 }
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 MISSING_OBJECT;
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->repo, &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(struct repository *r,
231 const struct object_id *oid,
232 void *cb_data_unused)
233 {
234 int kind = oid_object_info(r, oid, NULL);
235 return kind == OBJ_COMMIT;
236 }
237
238 static int disambiguate_committish_only(struct repository *r,
239 const struct object_id *oid,
240 void *cb_data_unused)
241 {
242 struct object *obj;
243 int kind;
244
245 kind = oid_object_info(r, oid, NULL);
246 if (kind == OBJ_COMMIT)
247 return 1;
248 if (kind != OBJ_TAG)
249 return 0;
250
251 /* We need to do this the hard way... */
252 obj = deref_tag(r, parse_object(r, oid), NULL, 0);
253 if (obj && obj->type == OBJ_COMMIT)
254 return 1;
255 return 0;
256 }
257
258 static int disambiguate_tree_only(struct repository *r,
259 const struct object_id *oid,
260 void *cb_data_unused)
261 {
262 int kind = oid_object_info(r, oid, NULL);
263 return kind == OBJ_TREE;
264 }
265
266 static int disambiguate_treeish_only(struct repository *r,
267 const struct object_id *oid,
268 void *cb_data_unused)
269 {
270 struct object *obj;
271 int kind;
272
273 kind = oid_object_info(r, oid, NULL);
274 if (kind == OBJ_TREE || kind == OBJ_COMMIT)
275 return 1;
276 if (kind != OBJ_TAG)
277 return 0;
278
279 /* We need to do this the hard way... */
280 obj = deref_tag(r, parse_object(r, oid), NULL, 0);
281 if (obj && (obj->type == OBJ_TREE || obj->type == OBJ_COMMIT))
282 return 1;
283 return 0;
284 }
285
286 static int disambiguate_blob_only(struct repository *r,
287 const struct object_id *oid,
288 void *cb_data_unused)
289 {
290 int kind = oid_object_info(r, oid, NULL);
291 return kind == OBJ_BLOB;
292 }
293
294 static disambiguate_hint_fn default_disambiguate_hint;
295
296 int set_disambiguate_hint_config(const char *var, const char *value)
297 {
298 static const struct {
299 const char *name;
300 disambiguate_hint_fn fn;
301 } hints[] = {
302 { "none", NULL },
303 { "commit", disambiguate_commit_only },
304 { "committish", disambiguate_committish_only },
305 { "tree", disambiguate_tree_only },
306 { "treeish", disambiguate_treeish_only },
307 { "blob", disambiguate_blob_only }
308 };
309 int i;
310
311 if (!value)
312 return config_error_nonbool(var);
313
314 for (i = 0; i < ARRAY_SIZE(hints); i++) {
315 if (!strcasecmp(value, hints[i].name)) {
316 default_disambiguate_hint = hints[i].fn;
317 return 0;
318 }
319 }
320
321 return error("unknown hint type for '%s': %s", var, value);
322 }
323
324 static int init_object_disambiguation(struct repository *r,
325 const char *name, int len,
326 struct disambiguate_state *ds)
327 {
328 int i;
329
330 if (len < MINIMUM_ABBREV || len > the_hash_algo->hexsz)
331 return -1;
332
333 memset(ds, 0, sizeof(*ds));
334
335 for (i = 0; i < len ;i++) {
336 unsigned char c = name[i];
337 unsigned char val;
338 if (c >= '0' && c <= '9')
339 val = c - '0';
340 else if (c >= 'a' && c <= 'f')
341 val = c - 'a' + 10;
342 else if (c >= 'A' && c <='F') {
343 val = c - 'A' + 10;
344 c -= 'A' - 'a';
345 }
346 else
347 return -1;
348 ds->hex_pfx[i] = c;
349 if (!(i & 1))
350 val <<= 4;
351 ds->bin_pfx.hash[i >> 1] |= val;
352 }
353
354 ds->len = len;
355 ds->hex_pfx[len] = '\0';
356 ds->repo = r;
357 prepare_alt_odb(r);
358 return 0;
359 }
360
361 static int show_ambiguous_object(const struct object_id *oid, void *data)
362 {
363 const struct disambiguate_state *ds = data;
364 struct strbuf desc = STRBUF_INIT;
365 int type;
366
367 if (ds->fn && !ds->fn(ds->repo, oid, ds->cb_data))
368 return 0;
369
370 type = oid_object_info(ds->repo, oid, NULL);
371 if (type == OBJ_COMMIT) {
372 struct commit *commit = lookup_commit(ds->repo, oid);
373 if (commit) {
374 struct pretty_print_context pp = {0};
375 pp.date_mode.type = DATE_SHORT;
376 format_commit_message(commit, " %ad - %s", &desc, &pp);
377 }
378 } else if (type == OBJ_TAG) {
379 struct tag *tag = lookup_tag(ds->repo, oid);
380 if (!parse_tag(tag) && tag->tag)
381 strbuf_addf(&desc, " %s", tag->tag);
382 }
383
384 advise(" %s %s%s",
385 repo_find_unique_abbrev(ds->repo, oid, DEFAULT_ABBREV),
386 type_name(type) ? type_name(type) : "unknown type",
387 desc.buf);
388
389 strbuf_release(&desc);
390 return 0;
391 }
392
393 static int collect_ambiguous(const struct object_id *oid, void *data)
394 {
395 oid_array_append(data, oid);
396 return 0;
397 }
398
399 static int repo_collect_ambiguous(struct repository *r,
400 const struct object_id *oid,
401 void *data)
402 {
403 return collect_ambiguous(oid, data);
404 }
405
406 static int sort_ambiguous(const void *a, const void *b, void *ctx)
407 {
408 struct repository *sort_ambiguous_repo = ctx;
409 int a_type = oid_object_info(sort_ambiguous_repo, a, NULL);
410 int b_type = oid_object_info(sort_ambiguous_repo, b, NULL);
411 int a_type_sort;
412 int b_type_sort;
413
414 /*
415 * Sorts by hash within the same object type, just as
416 * oid_array_for_each_unique() would do.
417 */
418 if (a_type == b_type)
419 return oidcmp(a, b);
420
421 /*
422 * Between object types show tags, then commits, and finally
423 * trees and blobs.
424 *
425 * The object_type enum is commit, tree, blob, tag, but we
426 * want tag, commit, tree blob. Cleverly (perhaps too
427 * cleverly) do that with modulus, since the enum assigns 1 to
428 * commit, so tag becomes 0.
429 */
430 a_type_sort = a_type % 4;
431 b_type_sort = b_type % 4;
432 return a_type_sort > b_type_sort ? 1 : -1;
433 }
434
435 static void sort_ambiguous_oid_array(struct repository *r, struct oid_array *a)
436 {
437 QSORT_S(a->oid, a->nr, sort_ambiguous, r);
438 }
439
440 static enum get_oid_result get_short_oid(struct repository *r,
441 const char *name, int len,
442 struct object_id *oid,
443 unsigned flags)
444 {
445 int status;
446 struct disambiguate_state ds;
447 int quietly = !!(flags & GET_OID_QUIETLY);
448
449 if (init_object_disambiguation(r, name, len, &ds) < 0)
450 return -1;
451
452 if (HAS_MULTI_BITS(flags & GET_OID_DISAMBIGUATORS))
453 BUG("multiple get_short_oid disambiguator flags");
454
455 if (flags & GET_OID_COMMIT)
456 ds.fn = disambiguate_commit_only;
457 else if (flags & GET_OID_COMMITTISH)
458 ds.fn = disambiguate_committish_only;
459 else if (flags & GET_OID_TREE)
460 ds.fn = disambiguate_tree_only;
461 else if (flags & GET_OID_TREEISH)
462 ds.fn = disambiguate_treeish_only;
463 else if (flags & GET_OID_BLOB)
464 ds.fn = disambiguate_blob_only;
465 else
466 ds.fn = default_disambiguate_hint;
467
468 find_short_object_filename(&ds);
469 find_short_packed_object(&ds);
470 status = finish_object_disambiguation(&ds, oid);
471
472 /*
473 * If we didn't find it, do the usual reprepare() slow-path,
474 * since the object may have recently been added to the repository
475 * or migrated from loose to packed.
476 */
477 if (status == MISSING_OBJECT) {
478 reprepare_packed_git(r);
479 find_short_object_filename(&ds);
480 find_short_packed_object(&ds);
481 status = finish_object_disambiguation(&ds, oid);
482 }
483
484 if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) {
485 struct oid_array collect = OID_ARRAY_INIT;
486
487 error(_("short SHA1 %s is ambiguous"), ds.hex_pfx);
488
489 /*
490 * We may still have ambiguity if we simply saw a series of
491 * candidates that did not satisfy our hint function. In
492 * that case, we still want to show them, so disable the hint
493 * function entirely.
494 */
495 if (!ds.ambiguous)
496 ds.fn = NULL;
497
498 advise(_("The candidates are:"));
499 repo_for_each_abbrev(r, ds.hex_pfx, collect_ambiguous, &collect);
500 sort_ambiguous_oid_array(r, &collect);
501
502 if (oid_array_for_each(&collect, show_ambiguous_object, &ds))
503 BUG("show_ambiguous_object shouldn't return non-zero");
504 oid_array_clear(&collect);
505 }
506
507 return status;
508 }
509
510 int repo_for_each_abbrev(struct repository *r, const char *prefix,
511 each_abbrev_fn fn, void *cb_data)
512 {
513 struct oid_array collect = OID_ARRAY_INIT;
514 struct disambiguate_state ds;
515 int ret;
516
517 if (init_object_disambiguation(r, prefix, strlen(prefix), &ds) < 0)
518 return -1;
519
520 ds.always_call_fn = 1;
521 ds.fn = repo_collect_ambiguous;
522 ds.cb_data = &collect;
523 find_short_object_filename(&ds);
524 find_short_packed_object(&ds);
525
526 ret = oid_array_for_each_unique(&collect, fn, cb_data);
527 oid_array_clear(&collect);
528 return ret;
529 }
530
531 /*
532 * Return the slot of the most-significant bit set in "val". There are various
533 * ways to do this quickly with fls() or __builtin_clzl(), but speed is
534 * probably not a big deal here.
535 */
536 static unsigned msb(unsigned long val)
537 {
538 unsigned r = 0;
539 while (val >>= 1)
540 r++;
541 return r;
542 }
543
544 struct min_abbrev_data {
545 unsigned int init_len;
546 unsigned int cur_len;
547 char *hex;
548 struct repository *repo;
549 const struct object_id *oid;
550 };
551
552 static inline char get_hex_char_from_oid(const struct object_id *oid,
553 unsigned int pos)
554 {
555 static const char hex[] = "0123456789abcdef";
556
557 if ((pos & 1) == 0)
558 return hex[oid->hash[pos >> 1] >> 4];
559 else
560 return hex[oid->hash[pos >> 1] & 0xf];
561 }
562
563 static int extend_abbrev_len(const struct object_id *oid, void *cb_data)
564 {
565 struct min_abbrev_data *mad = cb_data;
566
567 unsigned int i = mad->init_len;
568 while (mad->hex[i] && mad->hex[i] == get_hex_char_from_oid(oid, i))
569 i++;
570
571 if (i < GIT_MAX_RAWSZ && i >= mad->cur_len)
572 mad->cur_len = i + 1;
573
574 return 0;
575 }
576
577 static int repo_extend_abbrev_len(struct repository *r,
578 const struct object_id *oid,
579 void *cb_data)
580 {
581 return extend_abbrev_len(oid, cb_data);
582 }
583
584 static void find_abbrev_len_for_midx(struct multi_pack_index *m,
585 struct min_abbrev_data *mad)
586 {
587 int match = 0;
588 uint32_t num, first = 0;
589 struct object_id oid;
590 const struct object_id *mad_oid;
591
592 if (!m->num_objects)
593 return;
594
595 num = m->num_objects;
596 mad_oid = mad->oid;
597 match = bsearch_midx(mad_oid, m, &first);
598
599 /*
600 * first is now the position in the packfile where we would insert
601 * mad->hash if it does not exist (or the position of mad->hash if
602 * it does exist). Hence, we consider a maximum of two objects
603 * nearby for the abbreviation length.
604 */
605 mad->init_len = 0;
606 if (!match) {
607 if (nth_midxed_object_oid(&oid, m, first))
608 extend_abbrev_len(&oid, mad);
609 } else if (first < num - 1) {
610 if (nth_midxed_object_oid(&oid, m, first + 1))
611 extend_abbrev_len(&oid, mad);
612 }
613 if (first > 0) {
614 if (nth_midxed_object_oid(&oid, m, first - 1))
615 extend_abbrev_len(&oid, mad);
616 }
617 mad->init_len = mad->cur_len;
618 }
619
620 static void find_abbrev_len_for_pack(struct packed_git *p,
621 struct min_abbrev_data *mad)
622 {
623 int match = 0;
624 uint32_t num, first = 0;
625 struct object_id oid;
626 const struct object_id *mad_oid;
627
628 if (p->multi_pack_index)
629 return;
630
631 if (open_pack_index(p) || !p->num_objects)
632 return;
633
634 num = p->num_objects;
635 mad_oid = mad->oid;
636 match = bsearch_pack(mad_oid, p, &first);
637
638 /*
639 * first is now the position in the packfile where we would insert
640 * mad->hash if it does not exist (or the position of mad->hash if
641 * it does exist). Hence, we consider a maximum of two objects
642 * nearby for the abbreviation length.
643 */
644 mad->init_len = 0;
645 if (!match) {
646 if (nth_packed_object_oid(&oid, p, first))
647 extend_abbrev_len(&oid, mad);
648 } else if (first < num - 1) {
649 if (nth_packed_object_oid(&oid, p, first + 1))
650 extend_abbrev_len(&oid, mad);
651 }
652 if (first > 0) {
653 if (nth_packed_object_oid(&oid, p, first - 1))
654 extend_abbrev_len(&oid, mad);
655 }
656 mad->init_len = mad->cur_len;
657 }
658
659 static void find_abbrev_len_packed(struct min_abbrev_data *mad)
660 {
661 struct multi_pack_index *m;
662 struct packed_git *p;
663
664 for (m = get_multi_pack_index(mad->repo); m; m = m->next)
665 find_abbrev_len_for_midx(m, mad);
666 for (p = get_packed_git(mad->repo); p; p = p->next)
667 find_abbrev_len_for_pack(p, mad);
668 }
669
670 int repo_find_unique_abbrev_r(struct repository *r, char *hex,
671 const struct object_id *oid, int len)
672 {
673 struct disambiguate_state ds;
674 struct min_abbrev_data mad;
675 struct object_id oid_ret;
676 const unsigned hexsz = r->hash_algo->hexsz;
677
678 if (len < 0) {
679 unsigned long count = repo_approximate_object_count(r);
680 /*
681 * Add one because the MSB only tells us the highest bit set,
682 * not including the value of all the _other_ bits (so "15"
683 * is only one off of 2^4, but the MSB is the 3rd bit.
684 */
685 len = msb(count) + 1;
686 /*
687 * We now know we have on the order of 2^len objects, which
688 * expects a collision at 2^(len/2). But we also care about hex
689 * chars, not bits, and there are 4 bits per hex. So all
690 * together we need to divide by 2 and round up.
691 */
692 len = DIV_ROUND_UP(len, 2);
693 /*
694 * For very small repos, we stick with our regular fallback.
695 */
696 if (len < FALLBACK_DEFAULT_ABBREV)
697 len = FALLBACK_DEFAULT_ABBREV;
698 }
699
700 oid_to_hex_r(hex, oid);
701 if (len == hexsz || !len)
702 return hexsz;
703
704 mad.repo = r;
705 mad.init_len = len;
706 mad.cur_len = len;
707 mad.hex = hex;
708 mad.oid = oid;
709
710 find_abbrev_len_packed(&mad);
711
712 if (init_object_disambiguation(r, hex, mad.cur_len, &ds) < 0)
713 return -1;
714
715 ds.fn = repo_extend_abbrev_len;
716 ds.always_call_fn = 1;
717 ds.cb_data = (void *)&mad;
718
719 find_short_object_filename(&ds);
720 (void)finish_object_disambiguation(&ds, &oid_ret);
721
722 hex[mad.cur_len] = 0;
723 return mad.cur_len;
724 }
725
726 const char *repo_find_unique_abbrev(struct repository *r,
727 const struct object_id *oid,
728 int len)
729 {
730 static int bufno;
731 static char hexbuffer[4][GIT_MAX_HEXSZ + 1];
732 char *hex = hexbuffer[bufno];
733 bufno = (bufno + 1) % ARRAY_SIZE(hexbuffer);
734 repo_find_unique_abbrev_r(r, hex, oid, len);
735 return hex;
736 }
737
738 static int ambiguous_path(const char *path, int len)
739 {
740 int slash = 1;
741 int cnt;
742
743 for (cnt = 0; cnt < len; cnt++) {
744 switch (*path++) {
745 case '\0':
746 break;
747 case '/':
748 if (slash)
749 break;
750 slash = 1;
751 continue;
752 case '.':
753 continue;
754 default:
755 slash = 0;
756 continue;
757 }
758 break;
759 }
760 return slash;
761 }
762
763 static inline int at_mark(const char *string, int len,
764 const char **suffix, int nr)
765 {
766 int i;
767
768 for (i = 0; i < nr; i++) {
769 int suffix_len = strlen(suffix[i]);
770 if (suffix_len <= len
771 && !strncasecmp(string, suffix[i], suffix_len))
772 return suffix_len;
773 }
774 return 0;
775 }
776
777 static inline int upstream_mark(const char *string, int len)
778 {
779 const char *suffix[] = { "@{upstream}", "@{u}" };
780 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
781 }
782
783 static inline int push_mark(const char *string, int len)
784 {
785 const char *suffix[] = { "@{push}" };
786 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
787 }
788
789 static enum get_oid_result get_oid_1(struct repository *r, const char *name, int len, struct object_id *oid, unsigned lookup_flags);
790 static int interpret_nth_prior_checkout(struct repository *r, const char *name, int namelen, struct strbuf *buf);
791
792 static int get_oid_basic(struct repository *r, const char *str, int len,
793 struct object_id *oid, unsigned int flags)
794 {
795 static const char *warn_msg = "refname '%.*s' is ambiguous.";
796 static const char *object_name_msg = N_(
797 "Git normally never creates a ref that ends with 40 hex characters\n"
798 "because it will be ignored when you just specify 40-hex. These refs\n"
799 "may be created by mistake. For example,\n"
800 "\n"
801 " git switch -c $br $(git rev-parse ...)\n"
802 "\n"
803 "where \"$br\" is somehow empty and a 40-hex ref is created. Please\n"
804 "examine these refs and maybe delete them. Turn this message off by\n"
805 "running \"git config advice.objectNameWarning false\"");
806 struct object_id tmp_oid;
807 char *real_ref = NULL;
808 int refs_found = 0;
809 int at, reflog_len, nth_prior = 0;
810
811 if (len == r->hash_algo->hexsz && !get_oid_hex(str, oid)) {
812 if (warn_ambiguous_refs && warn_on_object_refname_ambiguity) {
813 refs_found = repo_dwim_ref(r, str, len, &tmp_oid, &real_ref);
814 if (refs_found > 0) {
815 warning(warn_msg, len, str);
816 if (advice_object_name_warning)
817 fprintf(stderr, "%s\n", _(object_name_msg));
818 }
819 free(real_ref);
820 }
821 return 0;
822 }
823
824 /* basic@{time or number or -number} format to query ref-log */
825 reflog_len = at = 0;
826 if (len && str[len-1] == '}') {
827 for (at = len-4; at >= 0; at--) {
828 if (str[at] == '@' && str[at+1] == '{') {
829 if (str[at+2] == '-') {
830 if (at != 0)
831 /* @{-N} not at start */
832 return -1;
833 nth_prior = 1;
834 continue;
835 }
836 if (!upstream_mark(str + at, len - at) &&
837 !push_mark(str + at, len - at)) {
838 reflog_len = (len-1) - (at+2);
839 len = at;
840 }
841 break;
842 }
843 }
844 }
845
846 /* Accept only unambiguous ref paths. */
847 if (len && ambiguous_path(str, len))
848 return -1;
849
850 if (nth_prior) {
851 struct strbuf buf = STRBUF_INIT;
852 int detached;
853
854 if (interpret_nth_prior_checkout(r, str, len, &buf) > 0) {
855 detached = (buf.len == r->hash_algo->hexsz && !get_oid_hex(buf.buf, oid));
856 strbuf_release(&buf);
857 if (detached)
858 return 0;
859 }
860 }
861
862 if (!len && reflog_len)
863 /* allow "@{...}" to mean the current branch reflog */
864 refs_found = repo_dwim_ref(r, "HEAD", 4, oid, &real_ref);
865 else if (reflog_len)
866 refs_found = repo_dwim_log(r, str, len, oid, &real_ref);
867 else
868 refs_found = repo_dwim_ref(r, str, len, oid, &real_ref);
869
870 if (!refs_found)
871 return -1;
872
873 if (warn_ambiguous_refs && !(flags & GET_OID_QUIETLY) &&
874 (refs_found > 1 ||
875 !get_short_oid(r, str, len, &tmp_oid, GET_OID_QUIETLY)))
876 warning(warn_msg, len, str);
877
878 if (reflog_len) {
879 int nth, i;
880 timestamp_t at_time;
881 timestamp_t co_time;
882 int co_tz, co_cnt;
883
884 /* Is it asking for N-th entry, or approxidate? */
885 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
886 char ch = str[at+2+i];
887 if ('0' <= ch && ch <= '9')
888 nth = nth * 10 + ch - '0';
889 else
890 nth = -1;
891 }
892 if (100000000 <= nth) {
893 at_time = nth;
894 nth = -1;
895 } else if (0 <= nth)
896 at_time = 0;
897 else {
898 int errors = 0;
899 char *tmp = xstrndup(str + at + 2, reflog_len);
900 at_time = approxidate_careful(tmp, &errors);
901 free(tmp);
902 if (errors) {
903 free(real_ref);
904 return -1;
905 }
906 }
907 if (read_ref_at(get_main_ref_store(r),
908 real_ref, flags, at_time, nth, oid, NULL,
909 &co_time, &co_tz, &co_cnt)) {
910 if (!len) {
911 if (starts_with(real_ref, "refs/heads/")) {
912 str = real_ref + 11;
913 len = strlen(real_ref + 11);
914 } else {
915 /* detached HEAD */
916 str = "HEAD";
917 len = 4;
918 }
919 }
920 if (at_time) {
921 if (!(flags & GET_OID_QUIETLY)) {
922 warning("Log for '%.*s' only goes "
923 "back to %s.", len, str,
924 show_date(co_time, co_tz, DATE_MODE(RFC2822)));
925 }
926 } else {
927 if (flags & GET_OID_QUIETLY) {
928 exit(128);
929 }
930 die("Log for '%.*s' only has %d entries.",
931 len, str, co_cnt);
932 }
933 }
934 }
935
936 free(real_ref);
937 return 0;
938 }
939
940 static enum get_oid_result get_parent(struct repository *r,
941 const char *name, int len,
942 struct object_id *result, int idx)
943 {
944 struct object_id oid;
945 enum get_oid_result ret = get_oid_1(r, name, len, &oid,
946 GET_OID_COMMITTISH);
947 struct commit *commit;
948 struct commit_list *p;
949
950 if (ret)
951 return ret;
952 commit = lookup_commit_reference(r, &oid);
953 if (parse_commit(commit))
954 return MISSING_OBJECT;
955 if (!idx) {
956 oidcpy(result, &commit->object.oid);
957 return FOUND;
958 }
959 p = commit->parents;
960 while (p) {
961 if (!--idx) {
962 oidcpy(result, &p->item->object.oid);
963 return FOUND;
964 }
965 p = p->next;
966 }
967 return MISSING_OBJECT;
968 }
969
970 static enum get_oid_result get_nth_ancestor(struct repository *r,
971 const char *name, int len,
972 struct object_id *result,
973 int generation)
974 {
975 struct object_id oid;
976 struct commit *commit;
977 int ret;
978
979 ret = get_oid_1(r, name, len, &oid, GET_OID_COMMITTISH);
980 if (ret)
981 return ret;
982 commit = lookup_commit_reference(r, &oid);
983 if (!commit)
984 return MISSING_OBJECT;
985
986 while (generation--) {
987 if (parse_commit(commit) || !commit->parents)
988 return MISSING_OBJECT;
989 commit = commit->parents->item;
990 }
991 oidcpy(result, &commit->object.oid);
992 return FOUND;
993 }
994
995 struct object *repo_peel_to_type(struct repository *r, const char *name, int namelen,
996 struct object *o, enum object_type expected_type)
997 {
998 if (name && !namelen)
999 namelen = strlen(name);
1000 while (1) {
1001 if (!o || (!o->parsed && !parse_object(r, &o->oid)))
1002 return NULL;
1003 if (expected_type == OBJ_ANY || o->type == expected_type)
1004 return o;
1005 if (o->type == OBJ_TAG)
1006 o = ((struct tag*) o)->tagged;
1007 else if (o->type == OBJ_COMMIT)
1008 o = &(repo_get_commit_tree(r, ((struct commit *)o))->object);
1009 else {
1010 if (name)
1011 error("%.*s: expected %s type, but the object "
1012 "dereferences to %s type",
1013 namelen, name, type_name(expected_type),
1014 type_name(o->type));
1015 return NULL;
1016 }
1017 }
1018 }
1019
1020 static int peel_onion(struct repository *r, const char *name, int len,
1021 struct object_id *oid, unsigned lookup_flags)
1022 {
1023 struct object_id outer;
1024 const char *sp;
1025 unsigned int expected_type = 0;
1026 struct object *o;
1027
1028 /*
1029 * "ref^{type}" dereferences ref repeatedly until you cannot
1030 * dereference anymore, or you get an object of given type,
1031 * whichever comes first. "ref^{}" means just dereference
1032 * tags until you get a non-tag. "ref^0" is a shorthand for
1033 * "ref^{commit}". "commit^{tree}" could be used to find the
1034 * top-level tree of the given commit.
1035 */
1036 if (len < 4 || name[len-1] != '}')
1037 return -1;
1038
1039 for (sp = name + len - 1; name <= sp; sp--) {
1040 int ch = *sp;
1041 if (ch == '{' && name < sp && sp[-1] == '^')
1042 break;
1043 }
1044 if (sp <= name)
1045 return -1;
1046
1047 sp++; /* beginning of type name, or closing brace for empty */
1048 if (starts_with(sp, "commit}"))
1049 expected_type = OBJ_COMMIT;
1050 else if (starts_with(sp, "tag}"))
1051 expected_type = OBJ_TAG;
1052 else if (starts_with(sp, "tree}"))
1053 expected_type = OBJ_TREE;
1054 else if (starts_with(sp, "blob}"))
1055 expected_type = OBJ_BLOB;
1056 else if (starts_with(sp, "object}"))
1057 expected_type = OBJ_ANY;
1058 else if (sp[0] == '}')
1059 expected_type = OBJ_NONE;
1060 else if (sp[0] == '/')
1061 expected_type = OBJ_COMMIT;
1062 else
1063 return -1;
1064
1065 lookup_flags &= ~GET_OID_DISAMBIGUATORS;
1066 if (expected_type == OBJ_COMMIT)
1067 lookup_flags |= GET_OID_COMMITTISH;
1068 else if (expected_type == OBJ_TREE)
1069 lookup_flags |= GET_OID_TREEISH;
1070
1071 if (get_oid_1(r, name, sp - name - 2, &outer, lookup_flags))
1072 return -1;
1073
1074 o = parse_object(r, &outer);
1075 if (!o)
1076 return -1;
1077 if (!expected_type) {
1078 o = deref_tag(r, o, name, sp - name - 2);
1079 if (!o || (!o->parsed && !parse_object(r, &o->oid)))
1080 return -1;
1081 oidcpy(oid, &o->oid);
1082 return 0;
1083 }
1084
1085 /*
1086 * At this point, the syntax look correct, so
1087 * if we do not get the needed object, we should
1088 * barf.
1089 */
1090 o = repo_peel_to_type(r, name, len, o, expected_type);
1091 if (!o)
1092 return -1;
1093
1094 oidcpy(oid, &o->oid);
1095 if (sp[0] == '/') {
1096 /* "$commit^{/foo}" */
1097 char *prefix;
1098 int ret;
1099 struct commit_list *list = NULL;
1100
1101 /*
1102 * $commit^{/}. Some regex implementation may reject.
1103 * We don't need regex anyway. '' pattern always matches.
1104 */
1105 if (sp[1] == '}')
1106 return 0;
1107
1108 prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
1109 commit_list_insert((struct commit *)o, &list);
1110 ret = get_oid_oneline(r, prefix, oid, list);
1111 free(prefix);
1112 return ret;
1113 }
1114 return 0;
1115 }
1116
1117 static int get_describe_name(struct repository *r,
1118 const char *name, int len,
1119 struct object_id *oid)
1120 {
1121 const char *cp;
1122 unsigned flags = GET_OID_QUIETLY | GET_OID_COMMIT;
1123
1124 for (cp = name + len - 1; name + 2 <= cp; cp--) {
1125 char ch = *cp;
1126 if (!isxdigit(ch)) {
1127 /* We must be looking at g in "SOMETHING-g"
1128 * for it to be describe output.
1129 */
1130 if (ch == 'g' && cp[-1] == '-') {
1131 cp++;
1132 len -= cp - name;
1133 return get_short_oid(r,
1134 cp, len, oid, flags);
1135 }
1136 }
1137 }
1138 return -1;
1139 }
1140
1141 static enum get_oid_result get_oid_1(struct repository *r,
1142 const char *name, int len,
1143 struct object_id *oid,
1144 unsigned lookup_flags)
1145 {
1146 int ret, has_suffix;
1147 const char *cp;
1148
1149 /*
1150 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
1151 */
1152 has_suffix = 0;
1153 for (cp = name + len - 1; name <= cp; cp--) {
1154 int ch = *cp;
1155 if ('0' <= ch && ch <= '9')
1156 continue;
1157 if (ch == '~' || ch == '^')
1158 has_suffix = ch;
1159 break;
1160 }
1161
1162 if (has_suffix) {
1163 int num = 0;
1164 int len1 = cp - name;
1165 cp++;
1166 while (cp < name + len)
1167 num = num * 10 + *cp++ - '0';
1168 if (!num && len1 == len - 1)
1169 num = 1;
1170 if (has_suffix == '^')
1171 return get_parent(r, name, len1, oid, num);
1172 /* else if (has_suffix == '~') -- goes without saying */
1173 return get_nth_ancestor(r, name, len1, oid, num);
1174 }
1175
1176 ret = peel_onion(r, name, len, oid, lookup_flags);
1177 if (!ret)
1178 return FOUND;
1179
1180 ret = get_oid_basic(r, name, len, oid, lookup_flags);
1181 if (!ret)
1182 return FOUND;
1183
1184 /* It could be describe output that is "SOMETHING-gXXXX" */
1185 ret = get_describe_name(r, name, len, oid);
1186 if (!ret)
1187 return FOUND;
1188
1189 return get_short_oid(r, name, len, oid, lookup_flags);
1190 }
1191
1192 /*
1193 * This interprets names like ':/Initial revision of "git"' by searching
1194 * through history and returning the first commit whose message starts
1195 * the given regular expression.
1196 *
1197 * For negative-matching, prefix the pattern-part with '!-', like: ':/!-WIP'.
1198 *
1199 * For a literal '!' character at the beginning of a pattern, you have to repeat
1200 * that, like: ':/!!foo'
1201 *
1202 * For future extension, all other sequences beginning with ':/!' are reserved.
1203 */
1204
1205 /* Remember to update object flag allocation in object.h */
1206 #define ONELINE_SEEN (1u<<20)
1207
1208 struct handle_one_ref_cb {
1209 struct repository *repo;
1210 struct commit_list **list;
1211 };
1212
1213 static int handle_one_ref(const char *path, const struct object_id *oid,
1214 int flag, void *cb_data)
1215 {
1216 struct handle_one_ref_cb *cb = cb_data;
1217 struct commit_list **list = cb->list;
1218 struct object *object = parse_object(cb->repo, oid);
1219 if (!object)
1220 return 0;
1221 if (object->type == OBJ_TAG) {
1222 object = deref_tag(cb->repo, object, path,
1223 strlen(path));
1224 if (!object)
1225 return 0;
1226 }
1227 if (object->type != OBJ_COMMIT)
1228 return 0;
1229 commit_list_insert((struct commit *)object, list);
1230 return 0;
1231 }
1232
1233 static int get_oid_oneline(struct repository *r,
1234 const char *prefix, struct object_id *oid,
1235 struct commit_list *list)
1236 {
1237 struct commit_list *backup = NULL, *l;
1238 int found = 0;
1239 int negative = 0;
1240 regex_t regex;
1241
1242 if (prefix[0] == '!') {
1243 prefix++;
1244
1245 if (prefix[0] == '-') {
1246 prefix++;
1247 negative = 1;
1248 } else if (prefix[0] != '!') {
1249 return -1;
1250 }
1251 }
1252
1253 if (regcomp(&regex, prefix, REG_EXTENDED))
1254 return -1;
1255
1256 for (l = list; l; l = l->next) {
1257 l->item->object.flags |= ONELINE_SEEN;
1258 commit_list_insert(l->item, &backup);
1259 }
1260 while (list) {
1261 const char *p, *buf;
1262 struct commit *commit;
1263 int matches;
1264
1265 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
1266 if (!parse_object(r, &commit->object.oid))
1267 continue;
1268 buf = get_commit_buffer(commit, NULL);
1269 p = strstr(buf, "\n\n");
1270 matches = negative ^ (p && !regexec(&regex, p + 2, 0, NULL, 0));
1271 unuse_commit_buffer(commit, buf);
1272
1273 if (matches) {
1274 oidcpy(oid, &commit->object.oid);
1275 found = 1;
1276 break;
1277 }
1278 }
1279 regfree(&regex);
1280 free_commit_list(list);
1281 for (l = backup; l; l = l->next)
1282 clear_commit_marks(l->item, ONELINE_SEEN);
1283 free_commit_list(backup);
1284 return found ? 0 : -1;
1285 }
1286
1287 struct grab_nth_branch_switch_cbdata {
1288 int remaining;
1289 struct strbuf buf;
1290 };
1291
1292 static int grab_nth_branch_switch(struct object_id *ooid, struct object_id *noid,
1293 const char *email, timestamp_t timestamp, int tz,
1294 const char *message, void *cb_data)
1295 {
1296 struct grab_nth_branch_switch_cbdata *cb = cb_data;
1297 const char *match = NULL, *target = NULL;
1298 size_t len;
1299
1300 if (skip_prefix(message, "checkout: moving from ", &match))
1301 target = strstr(match, " to ");
1302
1303 if (!match || !target)
1304 return 0;
1305 if (--(cb->remaining) == 0) {
1306 len = target - match;
1307 strbuf_reset(&cb->buf);
1308 strbuf_add(&cb->buf, match, len);
1309 return 1; /* we are done */
1310 }
1311 return 0;
1312 }
1313
1314 /*
1315 * Parse @{-N} syntax, return the number of characters parsed
1316 * if successful; otherwise signal an error with negative value.
1317 */
1318 static int interpret_nth_prior_checkout(struct repository *r,
1319 const char *name, int namelen,
1320 struct strbuf *buf)
1321 {
1322 long nth;
1323 int retval;
1324 struct grab_nth_branch_switch_cbdata cb;
1325 const char *brace;
1326 char *num_end;
1327
1328 if (namelen < 4)
1329 return -1;
1330 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
1331 return -1;
1332 brace = memchr(name, '}', namelen);
1333 if (!brace)
1334 return -1;
1335 nth = strtol(name + 3, &num_end, 10);
1336 if (num_end != brace)
1337 return -1;
1338 if (nth <= 0)
1339 return -1;
1340 cb.remaining = nth;
1341 strbuf_init(&cb.buf, 20);
1342
1343 retval = refs_for_each_reflog_ent_reverse(get_main_ref_store(r),
1344 "HEAD", grab_nth_branch_switch, &cb);
1345 if (0 < retval) {
1346 strbuf_reset(buf);
1347 strbuf_addbuf(buf, &cb.buf);
1348 retval = brace - name + 1;
1349 } else
1350 retval = 0;
1351
1352 strbuf_release(&cb.buf);
1353 return retval;
1354 }
1355
1356 int repo_get_oid_mb(struct repository *r,
1357 const char *name,
1358 struct object_id *oid)
1359 {
1360 struct commit *one, *two;
1361 struct commit_list *mbs;
1362 struct object_id oid_tmp;
1363 const char *dots;
1364 int st;
1365
1366 dots = strstr(name, "...");
1367 if (!dots)
1368 return repo_get_oid(r, name, oid);
1369 if (dots == name)
1370 st = repo_get_oid(r, "HEAD", &oid_tmp);
1371 else {
1372 struct strbuf sb;
1373 strbuf_init(&sb, dots - name);
1374 strbuf_add(&sb, name, dots - name);
1375 st = repo_get_oid_committish(r, sb.buf, &oid_tmp);
1376 strbuf_release(&sb);
1377 }
1378 if (st)
1379 return st;
1380 one = lookup_commit_reference_gently(r, &oid_tmp, 0);
1381 if (!one)
1382 return -1;
1383
1384 if (repo_get_oid_committish(r, dots[3] ? (dots + 3) : "HEAD", &oid_tmp))
1385 return -1;
1386 two = lookup_commit_reference_gently(r, &oid_tmp, 0);
1387 if (!two)
1388 return -1;
1389 mbs = repo_get_merge_bases(r, one, two);
1390 if (!mbs || mbs->next)
1391 st = -1;
1392 else {
1393 st = 0;
1394 oidcpy(oid, &mbs->item->object.oid);
1395 }
1396 free_commit_list(mbs);
1397 return st;
1398 }
1399
1400 /* parse @something syntax, when 'something' is not {.*} */
1401 static int interpret_empty_at(const char *name, int namelen, int len, struct strbuf *buf)
1402 {
1403 const char *next;
1404
1405 if (len || name[1] == '{')
1406 return -1;
1407
1408 /* make sure it's a single @, or @@{.*}, not @foo */
1409 next = memchr(name + len + 1, '@', namelen - len - 1);
1410 if (next && next[1] != '{')
1411 return -1;
1412 if (!next)
1413 next = name + namelen;
1414 if (next != name + 1)
1415 return -1;
1416
1417 strbuf_reset(buf);
1418 strbuf_add(buf, "HEAD", 4);
1419 return 1;
1420 }
1421
1422 static int reinterpret(struct repository *r,
1423 const char *name, int namelen, int len,
1424 struct strbuf *buf, unsigned allowed)
1425 {
1426 /* we have extra data, which might need further processing */
1427 struct strbuf tmp = STRBUF_INIT;
1428 int used = buf->len;
1429 int ret;
1430
1431 strbuf_add(buf, name + len, namelen - len);
1432 ret = repo_interpret_branch_name(r, buf->buf, buf->len, &tmp, allowed);
1433 /* that data was not interpreted, remove our cruft */
1434 if (ret < 0) {
1435 strbuf_setlen(buf, used);
1436 return len;
1437 }
1438 strbuf_reset(buf);
1439 strbuf_addbuf(buf, &tmp);
1440 strbuf_release(&tmp);
1441 /* tweak for size of {-N} versus expanded ref name */
1442 return ret - used + len;
1443 }
1444
1445 static void set_shortened_ref(struct repository *r, struct strbuf *buf, const char *ref)
1446 {
1447 char *s = refs_shorten_unambiguous_ref(get_main_ref_store(r), ref, 0);
1448 strbuf_reset(buf);
1449 strbuf_addstr(buf, s);
1450 free(s);
1451 }
1452
1453 static int branch_interpret_allowed(const char *refname, unsigned allowed)
1454 {
1455 if (!allowed)
1456 return 1;
1457
1458 if ((allowed & INTERPRET_BRANCH_LOCAL) &&
1459 starts_with(refname, "refs/heads/"))
1460 return 1;
1461 if ((allowed & INTERPRET_BRANCH_REMOTE) &&
1462 starts_with(refname, "refs/remotes/"))
1463 return 1;
1464
1465 return 0;
1466 }
1467
1468 static int interpret_branch_mark(struct repository *r,
1469 const char *name, int namelen,
1470 int at, struct strbuf *buf,
1471 int (*get_mark)(const char *, int),
1472 const char *(*get_data)(struct branch *,
1473 struct strbuf *),
1474 unsigned allowed)
1475 {
1476 int len;
1477 struct branch *branch;
1478 struct strbuf err = STRBUF_INIT;
1479 const char *value;
1480
1481 len = get_mark(name + at, namelen - at);
1482 if (!len)
1483 return -1;
1484
1485 if (memchr(name, ':', at))
1486 return -1;
1487
1488 if (at) {
1489 char *name_str = xmemdupz(name, at);
1490 branch = branch_get(name_str);
1491 free(name_str);
1492 } else
1493 branch = branch_get(NULL);
1494
1495 value = get_data(branch, &err);
1496 if (!value)
1497 die("%s", err.buf);
1498
1499 if (!branch_interpret_allowed(value, allowed))
1500 return -1;
1501
1502 set_shortened_ref(r, buf, value);
1503 return len + at;
1504 }
1505
1506 int repo_interpret_branch_name(struct repository *r,
1507 const char *name, int namelen,
1508 struct strbuf *buf,
1509 unsigned allowed)
1510 {
1511 char *at;
1512 const char *start;
1513 int len;
1514
1515 if (!namelen)
1516 namelen = strlen(name);
1517
1518 if (!allowed || (allowed & INTERPRET_BRANCH_LOCAL)) {
1519 len = interpret_nth_prior_checkout(r, name, namelen, buf);
1520 if (!len) {
1521 return len; /* syntax Ok, not enough switches */
1522 } else if (len > 0) {
1523 if (len == namelen)
1524 return len; /* consumed all */
1525 else
1526 return reinterpret(r, name, namelen, len, buf, allowed);
1527 }
1528 }
1529
1530 for (start = name;
1531 (at = memchr(start, '@', namelen - (start - name)));
1532 start = at + 1) {
1533
1534 if (!allowed || (allowed & INTERPRET_BRANCH_HEAD)) {
1535 len = interpret_empty_at(name, namelen, at - name, buf);
1536 if (len > 0)
1537 return reinterpret(r, name, namelen, len, buf,
1538 allowed);
1539 }
1540
1541 len = interpret_branch_mark(r, name, namelen, at - name, buf,
1542 upstream_mark, branch_get_upstream,
1543 allowed);
1544 if (len > 0)
1545 return len;
1546
1547 len = interpret_branch_mark(r, name, namelen, at - name, buf,
1548 push_mark, branch_get_push,
1549 allowed);
1550 if (len > 0)
1551 return len;
1552 }
1553
1554 return -1;
1555 }
1556
1557 void strbuf_branchname(struct strbuf *sb, const char *name, unsigned allowed)
1558 {
1559 int len = strlen(name);
1560 int used = interpret_branch_name(name, len, sb, allowed);
1561
1562 if (used < 0)
1563 used = 0;
1564 strbuf_add(sb, name + used, len - used);
1565 }
1566
1567 int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
1568 {
1569 if (startup_info->have_repository)
1570 strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
1571 else
1572 strbuf_addstr(sb, name);
1573
1574 /*
1575 * This splice must be done even if we end up rejecting the
1576 * name; builtin/branch.c::copy_or_rename_branch() still wants
1577 * to see what the name expanded to so that "branch -m" can be
1578 * used as a tool to correct earlier mistakes.
1579 */
1580 strbuf_splice(sb, 0, 0, "refs/heads/", 11);
1581
1582 if (*name == '-' ||
1583 !strcmp(sb->buf, "refs/heads/HEAD"))
1584 return -1;
1585
1586 return check_refname_format(sb->buf, 0);
1587 }
1588
1589 /*
1590 * This is like "get_oid_basic()", except it allows "object ID expressions",
1591 * notably "xyz^" for "parent of xyz"
1592 */
1593 int repo_get_oid(struct repository *r, const char *name, struct object_id *oid)
1594 {
1595 struct object_context unused;
1596 return get_oid_with_context(r, name, 0, oid, &unused);
1597 }
1598
1599 /*
1600 * This returns a non-zero value if the string (built using printf
1601 * format and the given arguments) is not a valid object.
1602 */
1603 int get_oidf(struct object_id *oid, const char *fmt, ...)
1604 {
1605 va_list ap;
1606 int ret;
1607 struct strbuf sb = STRBUF_INIT;
1608
1609 va_start(ap, fmt);
1610 strbuf_vaddf(&sb, fmt, ap);
1611 va_end(ap);
1612
1613 ret = get_oid(sb.buf, oid);
1614 strbuf_release(&sb);
1615
1616 return ret;
1617 }
1618
1619 /*
1620 * Many callers know that the user meant to name a commit-ish by
1621 * syntactical positions where the object name appears. Calling this
1622 * function allows the machinery to disambiguate shorter-than-unique
1623 * abbreviated object names between commit-ish and others.
1624 *
1625 * Note that this does NOT error out when the named object is not a
1626 * commit-ish. It is merely to give a hint to the disambiguation
1627 * machinery.
1628 */
1629 int repo_get_oid_committish(struct repository *r,
1630 const char *name,
1631 struct object_id *oid)
1632 {
1633 struct object_context unused;
1634 return get_oid_with_context(r, name, GET_OID_COMMITTISH,
1635 oid, &unused);
1636 }
1637
1638 int repo_get_oid_treeish(struct repository *r,
1639 const char *name,
1640 struct object_id *oid)
1641 {
1642 struct object_context unused;
1643 return get_oid_with_context(r, name, GET_OID_TREEISH,
1644 oid, &unused);
1645 }
1646
1647 int repo_get_oid_commit(struct repository *r,
1648 const char *name,
1649 struct object_id *oid)
1650 {
1651 struct object_context unused;
1652 return get_oid_with_context(r, name, GET_OID_COMMIT,
1653 oid, &unused);
1654 }
1655
1656 int repo_get_oid_tree(struct repository *r,
1657 const char *name,
1658 struct object_id *oid)
1659 {
1660 struct object_context unused;
1661 return get_oid_with_context(r, name, GET_OID_TREE,
1662 oid, &unused);
1663 }
1664
1665 int repo_get_oid_blob(struct repository *r,
1666 const char *name,
1667 struct object_id *oid)
1668 {
1669 struct object_context unused;
1670 return get_oid_with_context(r, name, GET_OID_BLOB,
1671 oid, &unused);
1672 }
1673
1674 /* Must be called only when object_name:filename doesn't exist. */
1675 static void diagnose_invalid_oid_path(struct repository *r,
1676 const char *prefix,
1677 const char *filename,
1678 const struct object_id *tree_oid,
1679 const char *object_name,
1680 int object_name_len)
1681 {
1682 struct object_id oid;
1683 unsigned short mode;
1684
1685 if (!prefix)
1686 prefix = "";
1687
1688 if (file_exists(filename))
1689 die("Path '%s' exists on disk, but not in '%.*s'.",
1690 filename, object_name_len, object_name);
1691 if (is_missing_file_error(errno)) {
1692 char *fullname = xstrfmt("%s%s", prefix, filename);
1693
1694 if (!get_tree_entry(r, tree_oid, fullname, &oid, &mode)) {
1695 die("Path '%s' exists, but not '%s'.\n"
1696 "Did you mean '%.*s:%s' aka '%.*s:./%s'?",
1697 fullname,
1698 filename,
1699 object_name_len, object_name,
1700 fullname,
1701 object_name_len, object_name,
1702 filename);
1703 }
1704 die("Path '%s' does not exist in '%.*s'",
1705 filename, object_name_len, object_name);
1706 }
1707 }
1708
1709 /* Must be called only when :stage:filename doesn't exist. */
1710 static void diagnose_invalid_index_path(struct repository *r,
1711 int stage,
1712 const char *prefix,
1713 const char *filename)
1714 {
1715 struct index_state *istate = r->index;
1716 const struct cache_entry *ce;
1717 int pos;
1718 unsigned namelen = strlen(filename);
1719 struct strbuf fullname = STRBUF_INIT;
1720
1721 if (!prefix)
1722 prefix = "";
1723
1724 /* Wrong stage number? */
1725 pos = index_name_pos(istate, filename, namelen);
1726 if (pos < 0)
1727 pos = -pos - 1;
1728 if (pos < istate->cache_nr) {
1729 ce = istate->cache[pos];
1730 if (ce_namelen(ce) == namelen &&
1731 !memcmp(ce->name, filename, namelen))
1732 die("Path '%s' is in the index, but not at stage %d.\n"
1733 "Did you mean ':%d:%s'?",
1734 filename, stage,
1735 ce_stage(ce), filename);
1736 }
1737
1738 /* Confusion between relative and absolute filenames? */
1739 strbuf_addstr(&fullname, prefix);
1740 strbuf_addstr(&fullname, filename);
1741 pos = index_name_pos(istate, fullname.buf, fullname.len);
1742 if (pos < 0)
1743 pos = -pos - 1;
1744 if (pos < istate->cache_nr) {
1745 ce = istate->cache[pos];
1746 if (ce_namelen(ce) == fullname.len &&
1747 !memcmp(ce->name, fullname.buf, fullname.len))
1748 die("Path '%s' is in the index, but not '%s'.\n"
1749 "Did you mean ':%d:%s' aka ':%d:./%s'?",
1750 fullname.buf, filename,
1751 ce_stage(ce), fullname.buf,
1752 ce_stage(ce), filename);
1753 }
1754
1755 if (repo_file_exists(r, filename))
1756 die("Path '%s' exists on disk, but not in the index.", filename);
1757 if (is_missing_file_error(errno))
1758 die("Path '%s' does not exist (neither on disk nor in the index).",
1759 filename);
1760
1761 strbuf_release(&fullname);
1762 }
1763
1764
1765 static char *resolve_relative_path(struct repository *r, const char *rel)
1766 {
1767 if (!starts_with(rel, "./") && !starts_with(rel, "../"))
1768 return NULL;
1769
1770 if (r != the_repository || !is_inside_work_tree())
1771 die("relative path syntax can't be used outside working tree.");
1772
1773 /* die() inside prefix_path() if resolved path is outside worktree */
1774 return prefix_path(startup_info->prefix,
1775 startup_info->prefix ? strlen(startup_info->prefix) : 0,
1776 rel);
1777 }
1778
1779 static enum get_oid_result get_oid_with_context_1(struct repository *repo,
1780 const char *name,
1781 unsigned flags,
1782 const char *prefix,
1783 struct object_id *oid,
1784 struct object_context *oc)
1785 {
1786 int ret, bracket_depth;
1787 int namelen = strlen(name);
1788 const char *cp;
1789 int only_to_die = flags & GET_OID_ONLY_TO_DIE;
1790
1791 if (only_to_die)
1792 flags |= GET_OID_QUIETLY;
1793
1794 memset(oc, 0, sizeof(*oc));
1795 oc->mode = S_IFINVALID;
1796 strbuf_init(&oc->symlink_path, 0);
1797 ret = get_oid_1(repo, name, namelen, oid, flags);
1798 if (!ret)
1799 return ret;
1800 /*
1801 * sha1:path --> object name of path in ent sha1
1802 * :path -> object name of absolute path in index
1803 * :./path -> object name of path relative to cwd in index
1804 * :[0-3]:path -> object name of path in index at stage
1805 * :/foo -> recent commit matching foo
1806 */
1807 if (name[0] == ':') {
1808 int stage = 0;
1809 const struct cache_entry *ce;
1810 char *new_path = NULL;
1811 int pos;
1812 if (!only_to_die && namelen > 2 && name[1] == '/') {
1813 struct handle_one_ref_cb cb;
1814 struct commit_list *list = NULL;
1815
1816 cb.repo = repo;
1817 cb.list = &list;
1818 refs_for_each_ref(repo->refs, handle_one_ref, &cb);
1819 refs_head_ref(repo->refs, handle_one_ref, &cb);
1820 commit_list_sort_by_date(&list);
1821 return get_oid_oneline(repo, name + 2, oid, list);
1822 }
1823 if (namelen < 3 ||
1824 name[2] != ':' ||
1825 name[1] < '0' || '3' < name[1])
1826 cp = name + 1;
1827 else {
1828 stage = name[1] - '0';
1829 cp = name + 3;
1830 }
1831 new_path = resolve_relative_path(repo, cp);
1832 if (!new_path) {
1833 namelen = namelen - (cp - name);
1834 } else {
1835 cp = new_path;
1836 namelen = strlen(cp);
1837 }
1838
1839 if (flags & GET_OID_RECORD_PATH)
1840 oc->path = xstrdup(cp);
1841
1842 if (!repo->index || !repo->index->cache)
1843 repo_read_index(repo);
1844 pos = index_name_pos(repo->index, cp, namelen);
1845 if (pos < 0)
1846 pos = -pos - 1;
1847 while (pos < repo->index->cache_nr) {
1848 ce = repo->index->cache[pos];
1849 if (ce_namelen(ce) != namelen ||
1850 memcmp(ce->name, cp, namelen))
1851 break;
1852 if (ce_stage(ce) == stage) {
1853 oidcpy(oid, &ce->oid);
1854 oc->mode = ce->ce_mode;
1855 free(new_path);
1856 return 0;
1857 }
1858 pos++;
1859 }
1860 if (only_to_die && name[1] && name[1] != '/')
1861 diagnose_invalid_index_path(repo, stage, prefix, cp);
1862 free(new_path);
1863 return -1;
1864 }
1865 for (cp = name, bracket_depth = 0; *cp; cp++) {
1866 if (*cp == '{')
1867 bracket_depth++;
1868 else if (bracket_depth && *cp == '}')
1869 bracket_depth--;
1870 else if (!bracket_depth && *cp == ':')
1871 break;
1872 }
1873 if (*cp == ':') {
1874 struct object_id tree_oid;
1875 int len = cp - name;
1876 unsigned sub_flags = flags;
1877
1878 sub_flags &= ~GET_OID_DISAMBIGUATORS;
1879 sub_flags |= GET_OID_TREEISH;
1880
1881 if (!get_oid_1(repo, name, len, &tree_oid, sub_flags)) {
1882 const char *filename = cp+1;
1883 char *new_filename = NULL;
1884
1885 new_filename = resolve_relative_path(repo, filename);
1886 if (new_filename)
1887 filename = new_filename;
1888 if (flags & GET_OID_FOLLOW_SYMLINKS) {
1889 ret = get_tree_entry_follow_symlinks(repo, &tree_oid,
1890 filename, oid, &oc->symlink_path,
1891 &oc->mode);
1892 } else {
1893 ret = get_tree_entry(repo, &tree_oid, filename, oid,
1894 &oc->mode);
1895 if (ret && only_to_die) {
1896 diagnose_invalid_oid_path(repo, prefix,
1897 filename,
1898 &tree_oid,
1899 name, len);
1900 }
1901 }
1902 if (flags & GET_OID_RECORD_PATH)
1903 oc->path = xstrdup(filename);
1904
1905 free(new_filename);
1906 return ret;
1907 } else {
1908 if (only_to_die)
1909 die("Invalid object name '%.*s'.", len, name);
1910 }
1911 }
1912 return ret;
1913 }
1914
1915 /*
1916 * Call this function when you know "name" given by the end user must
1917 * name an object but it doesn't; the function _may_ die with a better
1918 * diagnostic message than "no such object 'name'", e.g. "Path 'doc' does not
1919 * exist in 'HEAD'" when given "HEAD:doc", or it may return in which case
1920 * you have a chance to diagnose the error further.
1921 */
1922 void maybe_die_on_misspelt_object_name(struct repository *r,
1923 const char *name,
1924 const char *prefix)
1925 {
1926 struct object_context oc;
1927 struct object_id oid;
1928 get_oid_with_context_1(r, name, GET_OID_ONLY_TO_DIE,
1929 prefix, &oid, &oc);
1930 }
1931
1932 enum get_oid_result get_oid_with_context(struct repository *repo,
1933 const char *str,
1934 unsigned flags,
1935 struct object_id *oid,
1936 struct object_context *oc)
1937 {
1938 if (flags & GET_OID_FOLLOW_SYMLINKS && flags & GET_OID_ONLY_TO_DIE)
1939 BUG("incompatible flags for get_sha1_with_context");
1940 return get_oid_with_context_1(repo, str, flags, NULL, oid, oc);
1941 }