1#include "cache.h"
2#include "tag.h"
3#include "commit.h"
4#include "tree.h"
5#include "blob.h"
6#include "tree-walk.h"
7#include "refs.h"
8#include "remote.h"
9#include "dir.h"
10#include "sha1-array.h"
11
12static int get_sha1_oneline(const char *, unsigned char *, struct commit_list *);
13
14typedef int (*disambiguate_hint_fn)(const unsigned char *, void *);
15
16struct disambiguate_state {
17 int len; /* length of prefix in hex chars */
18 char hex_pfx[GIT_SHA1_HEXSZ + 1];
19 unsigned char bin_pfx[GIT_SHA1_RAWSZ];
20
21 disambiguate_hint_fn fn;
22 void *cb_data;
23 unsigned char candidate[GIT_SHA1_RAWSZ];
24 unsigned candidate_exists:1;
25 unsigned candidate_checked:1;
26 unsigned candidate_ok:1;
27 unsigned disambiguate_fn_used:1;
28 unsigned ambiguous:1;
29 unsigned always_call_fn:1;
30};
31
32static void update_candidates(struct disambiguate_state *ds, const unsigned char *current)
33{
34 if (ds->always_call_fn) {
35 ds->ambiguous = ds->fn(current, ds->cb_data) ? 1 : 0;
36 return;
37 }
38 if (!ds->candidate_exists) {
39 /* this is the first candidate */
40 hashcpy(ds->candidate, current);
41 ds->candidate_exists = 1;
42 return;
43 } else if (!hashcmp(ds->candidate, current)) {
44 /* the same as what we already have seen */
45 return;
46 }
47
48 if (!ds->fn) {
49 /* cannot disambiguate between ds->candidate and current */
50 ds->ambiguous = 1;
51 return;
52 }
53
54 if (!ds->candidate_checked) {
55 ds->candidate_ok = ds->fn(ds->candidate, ds->cb_data);
56 ds->disambiguate_fn_used = 1;
57 ds->candidate_checked = 1;
58 }
59
60 if (!ds->candidate_ok) {
61 /* discard the candidate; we know it does not satisfy fn */
62 hashcpy(ds->candidate, current);
63 ds->candidate_checked = 0;
64 return;
65 }
66
67 /* if we reach this point, we know ds->candidate satisfies fn */
68 if (ds->fn(current, ds->cb_data)) {
69 /*
70 * if both current and candidate satisfy fn, we cannot
71 * disambiguate.
72 */
73 ds->candidate_ok = 0;
74 ds->ambiguous = 1;
75 }
76
77 /* otherwise, current can be discarded and candidate is still good */
78}
79
80static void find_short_object_filename(struct disambiguate_state *ds)
81{
82 struct alternate_object_database *alt;
83 char hex[GIT_SHA1_HEXSZ];
84 static struct alternate_object_database *fakeent;
85
86 if (!fakeent) {
87 /*
88 * Create a "fake" alternate object database that
89 * points to our own object database, to make it
90 * easier to get a temporary working space in
91 * alt->name/alt->base while iterating over the
92 * object databases including our own.
93 */
94 fakeent = alloc_alt_odb(get_object_directory());
95 }
96 fakeent->next = alt_odb_list;
97
98 xsnprintf(hex, sizeof(hex), "%.2s", ds->hex_pfx);
99 for (alt = fakeent; alt && !ds->ambiguous; alt = alt->next) {
100 struct strbuf *buf = alt_scratch_buf(alt);
101 struct dirent *de;
102 DIR *dir;
103
104 strbuf_addf(buf, "%.2s/", ds->hex_pfx);
105 dir = opendir(buf->buf);
106 if (!dir)
107 continue;
108
109 while (!ds->ambiguous && (de = readdir(dir)) != NULL) {
110 unsigned char sha1[20];
111
112 if (strlen(de->d_name) != 38)
113 continue;
114 if (memcmp(de->d_name, ds->hex_pfx + 2, ds->len - 2))
115 continue;
116 memcpy(hex + 2, de->d_name, 38);
117 if (!get_sha1_hex(hex, sha1))
118 update_candidates(ds, sha1);
119 }
120 closedir(dir);
121 }
122}
123
124static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
125{
126 do {
127 if (*a != *b)
128 return 0;
129 a++;
130 b++;
131 len -= 2;
132 } while (len > 1);
133 if (len)
134 if ((*a ^ *b) & 0xf0)
135 return 0;
136 return 1;
137}
138
139static void unique_in_pack(struct packed_git *p,
140 struct disambiguate_state *ds)
141{
142 uint32_t num, last, i, first = 0;
143 const unsigned char *current = NULL;
144
145 open_pack_index(p);
146 num = p->num_objects;
147 last = num;
148 while (first < last) {
149 uint32_t mid = (first + last) / 2;
150 const unsigned char *current;
151 int cmp;
152
153 current = nth_packed_object_sha1(p, mid);
154 cmp = hashcmp(ds->bin_pfx, current);
155 if (!cmp) {
156 first = mid;
157 break;
158 }
159 if (cmp > 0) {
160 first = mid+1;
161 continue;
162 }
163 last = mid;
164 }
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 current = nth_packed_object_sha1(p, i);
173 if (!match_sha(ds->len, ds->bin_pfx, current))
174 break;
175 update_candidates(ds, current);
176 }
177}
178
179static void find_short_packed_object(struct disambiguate_state *ds)
180{
181 struct packed_git *p;
182
183 prepare_packed_git();
184 for (p = packed_git; p && !ds->ambiguous; p = p->next)
185 unique_in_pack(p, ds);
186}
187
188#define SHORT_NAME_NOT_FOUND (-1)
189#define SHORT_NAME_AMBIGUOUS (-2)
190
191static int finish_object_disambiguation(struct disambiguate_state *ds,
192 unsigned char *sha1)
193{
194 if (ds->ambiguous)
195 return SHORT_NAME_AMBIGUOUS;
196
197 if (!ds->candidate_exists)
198 return SHORT_NAME_NOT_FOUND;
199
200 if (!ds->candidate_checked)
201 /*
202 * If this is the only candidate, there is no point
203 * calling the disambiguation hint callback.
204 *
205 * On the other hand, if the current candidate
206 * replaced an earlier candidate that did _not_ pass
207 * the disambiguation hint callback, then we do have
208 * more than one objects that match the short name
209 * given, so we should make sure this one matches;
210 * otherwise, if we discovered this one and the one
211 * that we previously discarded in the reverse order,
212 * we would end up showing different results in the
213 * same repository!
214 */
215 ds->candidate_ok = (!ds->disambiguate_fn_used ||
216 ds->fn(ds->candidate, ds->cb_data));
217
218 if (!ds->candidate_ok)
219 return SHORT_NAME_AMBIGUOUS;
220
221 hashcpy(sha1, ds->candidate);
222 return 0;
223}
224
225static int disambiguate_commit_only(const unsigned char *sha1, void *cb_data_unused)
226{
227 int kind = sha1_object_info(sha1, NULL);
228 return kind == OBJ_COMMIT;
229}
230
231static int disambiguate_committish_only(const unsigned char *sha1, void *cb_data_unused)
232{
233 struct object *obj;
234 int kind;
235
236 kind = sha1_object_info(sha1, NULL);
237 if (kind == OBJ_COMMIT)
238 return 1;
239 if (kind != OBJ_TAG)
240 return 0;
241
242 /* We need to do this the hard way... */
243 obj = deref_tag(parse_object(sha1), NULL, 0);
244 if (obj && obj->type == OBJ_COMMIT)
245 return 1;
246 return 0;
247}
248
249static int disambiguate_tree_only(const unsigned char *sha1, void *cb_data_unused)
250{
251 int kind = sha1_object_info(sha1, NULL);
252 return kind == OBJ_TREE;
253}
254
255static int disambiguate_treeish_only(const unsigned char *sha1, void *cb_data_unused)
256{
257 struct object *obj;
258 int kind;
259
260 kind = sha1_object_info(sha1, NULL);
261 if (kind == OBJ_TREE || kind == OBJ_COMMIT)
262 return 1;
263 if (kind != OBJ_TAG)
264 return 0;
265
266 /* We need to do this the hard way... */
267 obj = deref_tag(parse_object(sha1), NULL, 0);
268 if (obj && (obj->type == OBJ_TREE || obj->type == OBJ_COMMIT))
269 return 1;
270 return 0;
271}
272
273static int disambiguate_blob_only(const unsigned char *sha1, void *cb_data_unused)
274{
275 int kind = sha1_object_info(sha1, NULL);
276 return kind == OBJ_BLOB;
277}
278
279static disambiguate_hint_fn default_disambiguate_hint;
280
281int set_disambiguate_hint_config(const char *var, const char *value)
282{
283 static const struct {
284 const char *name;
285 disambiguate_hint_fn fn;
286 } hints[] = {
287 { "none", NULL },
288 { "commit", disambiguate_commit_only },
289 { "committish", disambiguate_committish_only },
290 { "tree", disambiguate_tree_only },
291 { "treeish", disambiguate_treeish_only },
292 { "blob", disambiguate_blob_only }
293 };
294 int i;
295
296 if (!value)
297 return config_error_nonbool(var);
298
299 for (i = 0; i < ARRAY_SIZE(hints); i++) {
300 if (!strcasecmp(value, hints[i].name)) {
301 default_disambiguate_hint = hints[i].fn;
302 return 0;
303 }
304 }
305
306 return error("unknown hint type for '%s': %s", var, value);
307}
308
309static int init_object_disambiguation(const char *name, int len,
310 struct disambiguate_state *ds)
311{
312 int i;
313
314 if (len < MINIMUM_ABBREV || len > GIT_SHA1_HEXSZ)
315 return -1;
316
317 memset(ds, 0, sizeof(*ds));
318
319 for (i = 0; i < len ;i++) {
320 unsigned char c = name[i];
321 unsigned char val;
322 if (c >= '0' && c <= '9')
323 val = c - '0';
324 else if (c >= 'a' && c <= 'f')
325 val = c - 'a' + 10;
326 else if (c >= 'A' && c <='F') {
327 val = c - 'A' + 10;
328 c -= 'A' - 'a';
329 }
330 else
331 return -1;
332 ds->hex_pfx[i] = c;
333 if (!(i & 1))
334 val <<= 4;
335 ds->bin_pfx[i >> 1] |= val;
336 }
337
338 ds->len = len;
339 ds->hex_pfx[len] = '\0';
340 prepare_alt_odb();
341 return 0;
342}
343
344static int show_ambiguous_object(const unsigned char *sha1, void *data)
345{
346 const struct disambiguate_state *ds = data;
347 struct strbuf desc = STRBUF_INIT;
348 int type;
349
350 if (ds->fn && !ds->fn(sha1, ds->cb_data))
351 return 0;
352
353 type = sha1_object_info(sha1, NULL);
354 if (type == OBJ_COMMIT) {
355 struct commit *commit = lookup_commit(sha1);
356 if (commit) {
357 struct pretty_print_context pp = {0};
358 pp.date_mode.type = DATE_SHORT;
359 format_commit_message(commit, " %ad - %s", &desc, &pp);
360 }
361 } else if (type == OBJ_TAG) {
362 struct tag *tag = lookup_tag(sha1);
363 if (!parse_tag(tag) && tag->tag)
364 strbuf_addf(&desc, " %s", tag->tag);
365 }
366
367 advise(" %s %s%s",
368 find_unique_abbrev(sha1, DEFAULT_ABBREV),
369 typename(type) ? typename(type) : "unknown type",
370 desc.buf);
371
372 strbuf_release(&desc);
373 return 0;
374}
375
376static int get_short_sha1(const char *name, int len, unsigned char *sha1,
377 unsigned flags)
378{
379 int status;
380 struct disambiguate_state ds;
381 int quietly = !!(flags & GET_SHA1_QUIETLY);
382
383 if (init_object_disambiguation(name, len, &ds) < 0)
384 return -1;
385
386 if (HAS_MULTI_BITS(flags & GET_SHA1_DISAMBIGUATORS))
387 die("BUG: multiple get_short_sha1 disambiguator flags");
388
389 if (flags & GET_SHA1_COMMIT)
390 ds.fn = disambiguate_commit_only;
391 else if (flags & GET_SHA1_COMMITTISH)
392 ds.fn = disambiguate_committish_only;
393 else if (flags & GET_SHA1_TREE)
394 ds.fn = disambiguate_tree_only;
395 else if (flags & GET_SHA1_TREEISH)
396 ds.fn = disambiguate_treeish_only;
397 else if (flags & GET_SHA1_BLOB)
398 ds.fn = disambiguate_blob_only;
399 else
400 ds.fn = default_disambiguate_hint;
401
402 find_short_object_filename(&ds);
403 find_short_packed_object(&ds);
404 status = finish_object_disambiguation(&ds, sha1);
405
406 if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) {
407 error(_("short SHA1 %s is ambiguous"), ds.hex_pfx);
408
409 /*
410 * We may still have ambiguity if we simply saw a series of
411 * candidates that did not satisfy our hint function. In
412 * that case, we still want to show them, so disable the hint
413 * function entirely.
414 */
415 if (!ds.ambiguous)
416 ds.fn = NULL;
417
418 advise(_("The candidates are:"));
419 for_each_abbrev(ds.hex_pfx, show_ambiguous_object, &ds);
420 }
421
422 return status;
423}
424
425static int collect_ambiguous(const unsigned char *sha1, void *data)
426{
427 sha1_array_append(data, sha1);
428 return 0;
429}
430
431int for_each_abbrev(const char *prefix, each_abbrev_fn fn, void *cb_data)
432{
433 struct sha1_array collect = SHA1_ARRAY_INIT;
434 struct disambiguate_state ds;
435 int ret;
436
437 if (init_object_disambiguation(prefix, strlen(prefix), &ds) < 0)
438 return -1;
439
440 ds.always_call_fn = 1;
441 ds.fn = collect_ambiguous;
442 ds.cb_data = &collect;
443 find_short_object_filename(&ds);
444 find_short_packed_object(&ds);
445
446 ret = sha1_array_for_each_unique(&collect, fn, cb_data);
447 sha1_array_clear(&collect);
448 return ret;
449}
450
451int find_unique_abbrev_r(char *hex, const unsigned char *sha1, int len)
452{
453 int status, exists;
454
455 sha1_to_hex_r(hex, sha1);
456 if (len == 40 || !len)
457 return 40;
458 exists = has_sha1_file(sha1);
459 while (len < 40) {
460 unsigned char sha1_ret[20];
461 status = get_short_sha1(hex, len, sha1_ret, GET_SHA1_QUIETLY);
462 if (exists
463 ? !status
464 : status == SHORT_NAME_NOT_FOUND) {
465 hex[len] = 0;
466 return len;
467 }
468 len++;
469 }
470 return len;
471}
472
473const char *find_unique_abbrev(const unsigned char *sha1, int len)
474{
475 static char hex[GIT_SHA1_HEXSZ + 1];
476 find_unique_abbrev_r(hex, sha1, len);
477 return hex;
478}
479
480static int ambiguous_path(const char *path, int len)
481{
482 int slash = 1;
483 int cnt;
484
485 for (cnt = 0; cnt < len; cnt++) {
486 switch (*path++) {
487 case '\0':
488 break;
489 case '/':
490 if (slash)
491 break;
492 slash = 1;
493 continue;
494 case '.':
495 continue;
496 default:
497 slash = 0;
498 continue;
499 }
500 break;
501 }
502 return slash;
503}
504
505static inline int at_mark(const char *string, int len,
506 const char **suffix, int nr)
507{
508 int i;
509
510 for (i = 0; i < nr; i++) {
511 int suffix_len = strlen(suffix[i]);
512 if (suffix_len <= len
513 && !memcmp(string, suffix[i], suffix_len))
514 return suffix_len;
515 }
516 return 0;
517}
518
519static inline int upstream_mark(const char *string, int len)
520{
521 const char *suffix[] = { "@{upstream}", "@{u}" };
522 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
523}
524
525static inline int push_mark(const char *string, int len)
526{
527 const char *suffix[] = { "@{push}" };
528 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
529}
530
531static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags);
532static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
533
534static int get_sha1_basic(const char *str, int len, unsigned char *sha1,
535 unsigned int flags)
536{
537 static const char *warn_msg = "refname '%.*s' is ambiguous.";
538 static const char *object_name_msg = N_(
539 "Git normally never creates a ref that ends with 40 hex characters\n"
540 "because it will be ignored when you just specify 40-hex. These refs\n"
541 "may be created by mistake. For example,\n"
542 "\n"
543 " git checkout -b $br $(git rev-parse ...)\n"
544 "\n"
545 "where \"$br\" is somehow empty and a 40-hex ref is created. Please\n"
546 "examine these refs and maybe delete them. Turn this message off by\n"
547 "running \"git config advice.objectNameWarning false\"");
548 unsigned char tmp_sha1[20];
549 char *real_ref = NULL;
550 int refs_found = 0;
551 int at, reflog_len, nth_prior = 0;
552
553 if (len == 40 && !get_sha1_hex(str, sha1)) {
554 if (warn_ambiguous_refs && warn_on_object_refname_ambiguity) {
555 refs_found = dwim_ref(str, len, tmp_sha1, &real_ref);
556 if (refs_found > 0) {
557 warning(warn_msg, len, str);
558 if (advice_object_name_warning)
559 fprintf(stderr, "%s\n", _(object_name_msg));
560 }
561 free(real_ref);
562 }
563 return 0;
564 }
565
566 /* basic@{time or number or -number} format to query ref-log */
567 reflog_len = at = 0;
568 if (len && str[len-1] == '}') {
569 for (at = len-4; at >= 0; at--) {
570 if (str[at] == '@' && str[at+1] == '{') {
571 if (str[at+2] == '-') {
572 if (at != 0)
573 /* @{-N} not at start */
574 return -1;
575 nth_prior = 1;
576 continue;
577 }
578 if (!upstream_mark(str + at, len - at) &&
579 !push_mark(str + at, len - at)) {
580 reflog_len = (len-1) - (at+2);
581 len = at;
582 }
583 break;
584 }
585 }
586 }
587
588 /* Accept only unambiguous ref paths. */
589 if (len && ambiguous_path(str, len))
590 return -1;
591
592 if (nth_prior) {
593 struct strbuf buf = STRBUF_INIT;
594 int detached;
595
596 if (interpret_nth_prior_checkout(str, len, &buf) > 0) {
597 detached = (buf.len == 40 && !get_sha1_hex(buf.buf, sha1));
598 strbuf_release(&buf);
599 if (detached)
600 return 0;
601 }
602 }
603
604 if (!len && reflog_len)
605 /* allow "@{...}" to mean the current branch reflog */
606 refs_found = dwim_ref("HEAD", 4, sha1, &real_ref);
607 else if (reflog_len)
608 refs_found = dwim_log(str, len, sha1, &real_ref);
609 else
610 refs_found = dwim_ref(str, len, sha1, &real_ref);
611
612 if (!refs_found)
613 return -1;
614
615 if (warn_ambiguous_refs && !(flags & GET_SHA1_QUIETLY) &&
616 (refs_found > 1 ||
617 !get_short_sha1(str, len, tmp_sha1, GET_SHA1_QUIETLY)))
618 warning(warn_msg, len, str);
619
620 if (reflog_len) {
621 int nth, i;
622 unsigned long at_time;
623 unsigned long co_time;
624 int co_tz, co_cnt;
625
626 /* Is it asking for N-th entry, or approxidate? */
627 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
628 char ch = str[at+2+i];
629 if ('0' <= ch && ch <= '9')
630 nth = nth * 10 + ch - '0';
631 else
632 nth = -1;
633 }
634 if (100000000 <= nth) {
635 at_time = nth;
636 nth = -1;
637 } else if (0 <= nth)
638 at_time = 0;
639 else {
640 int errors = 0;
641 char *tmp = xstrndup(str + at + 2, reflog_len);
642 at_time = approxidate_careful(tmp, &errors);
643 free(tmp);
644 if (errors) {
645 free(real_ref);
646 return -1;
647 }
648 }
649 if (read_ref_at(real_ref, flags, at_time, nth, sha1, NULL,
650 &co_time, &co_tz, &co_cnt)) {
651 if (!len) {
652 if (starts_with(real_ref, "refs/heads/")) {
653 str = real_ref + 11;
654 len = strlen(real_ref + 11);
655 } else {
656 /* detached HEAD */
657 str = "HEAD";
658 len = 4;
659 }
660 }
661 if (at_time) {
662 if (!(flags & GET_SHA1_QUIETLY)) {
663 warning("Log for '%.*s' only goes "
664 "back to %s.", len, str,
665 show_date(co_time, co_tz, DATE_MODE(RFC2822)));
666 }
667 } else {
668 if (flags & GET_SHA1_QUIETLY) {
669 exit(128);
670 }
671 die("Log for '%.*s' only has %d entries.",
672 len, str, co_cnt);
673 }
674 }
675 }
676
677 free(real_ref);
678 return 0;
679}
680
681static int get_parent(const char *name, int len,
682 unsigned char *result, int idx)
683{
684 unsigned char sha1[20];
685 int ret = get_sha1_1(name, len, sha1, GET_SHA1_COMMITTISH);
686 struct commit *commit;
687 struct commit_list *p;
688
689 if (ret)
690 return ret;
691 commit = lookup_commit_reference(sha1);
692 if (parse_commit(commit))
693 return -1;
694 if (!idx) {
695 hashcpy(result, commit->object.oid.hash);
696 return 0;
697 }
698 p = commit->parents;
699 while (p) {
700 if (!--idx) {
701 hashcpy(result, p->item->object.oid.hash);
702 return 0;
703 }
704 p = p->next;
705 }
706 return -1;
707}
708
709static int get_nth_ancestor(const char *name, int len,
710 unsigned char *result, int generation)
711{
712 unsigned char sha1[20];
713 struct commit *commit;
714 int ret;
715
716 ret = get_sha1_1(name, len, sha1, GET_SHA1_COMMITTISH);
717 if (ret)
718 return ret;
719 commit = lookup_commit_reference(sha1);
720 if (!commit)
721 return -1;
722
723 while (generation--) {
724 if (parse_commit(commit) || !commit->parents)
725 return -1;
726 commit = commit->parents->item;
727 }
728 hashcpy(result, commit->object.oid.hash);
729 return 0;
730}
731
732struct object *peel_to_type(const char *name, int namelen,
733 struct object *o, enum object_type expected_type)
734{
735 if (name && !namelen)
736 namelen = strlen(name);
737 while (1) {
738 if (!o || (!o->parsed && !parse_object(o->oid.hash)))
739 return NULL;
740 if (expected_type == OBJ_ANY || o->type == expected_type)
741 return o;
742 if (o->type == OBJ_TAG)
743 o = ((struct tag*) o)->tagged;
744 else if (o->type == OBJ_COMMIT)
745 o = &(((struct commit *) o)->tree->object);
746 else {
747 if (name)
748 error("%.*s: expected %s type, but the object "
749 "dereferences to %s type",
750 namelen, name, typename(expected_type),
751 typename(o->type));
752 return NULL;
753 }
754 }
755}
756
757static int peel_onion(const char *name, int len, unsigned char *sha1,
758 unsigned lookup_flags)
759{
760 unsigned char outer[20];
761 const char *sp;
762 unsigned int expected_type = 0;
763 struct object *o;
764
765 /*
766 * "ref^{type}" dereferences ref repeatedly until you cannot
767 * dereference anymore, or you get an object of given type,
768 * whichever comes first. "ref^{}" means just dereference
769 * tags until you get a non-tag. "ref^0" is a shorthand for
770 * "ref^{commit}". "commit^{tree}" could be used to find the
771 * top-level tree of the given commit.
772 */
773 if (len < 4 || name[len-1] != '}')
774 return -1;
775
776 for (sp = name + len - 1; name <= sp; sp--) {
777 int ch = *sp;
778 if (ch == '{' && name < sp && sp[-1] == '^')
779 break;
780 }
781 if (sp <= name)
782 return -1;
783
784 sp++; /* beginning of type name, or closing brace for empty */
785 if (starts_with(sp, "commit}"))
786 expected_type = OBJ_COMMIT;
787 else if (starts_with(sp, "tag}"))
788 expected_type = OBJ_TAG;
789 else if (starts_with(sp, "tree}"))
790 expected_type = OBJ_TREE;
791 else if (starts_with(sp, "blob}"))
792 expected_type = OBJ_BLOB;
793 else if (starts_with(sp, "object}"))
794 expected_type = OBJ_ANY;
795 else if (sp[0] == '}')
796 expected_type = OBJ_NONE;
797 else if (sp[0] == '/')
798 expected_type = OBJ_COMMIT;
799 else
800 return -1;
801
802 lookup_flags &= ~GET_SHA1_DISAMBIGUATORS;
803 if (expected_type == OBJ_COMMIT)
804 lookup_flags |= GET_SHA1_COMMITTISH;
805 else if (expected_type == OBJ_TREE)
806 lookup_flags |= GET_SHA1_TREEISH;
807
808 if (get_sha1_1(name, sp - name - 2, outer, lookup_flags))
809 return -1;
810
811 o = parse_object(outer);
812 if (!o)
813 return -1;
814 if (!expected_type) {
815 o = deref_tag(o, name, sp - name - 2);
816 if (!o || (!o->parsed && !parse_object(o->oid.hash)))
817 return -1;
818 hashcpy(sha1, o->oid.hash);
819 return 0;
820 }
821
822 /*
823 * At this point, the syntax look correct, so
824 * if we do not get the needed object, we should
825 * barf.
826 */
827 o = peel_to_type(name, len, o, expected_type);
828 if (!o)
829 return -1;
830
831 hashcpy(sha1, o->oid.hash);
832 if (sp[0] == '/') {
833 /* "$commit^{/foo}" */
834 char *prefix;
835 int ret;
836 struct commit_list *list = NULL;
837
838 /*
839 * $commit^{/}. Some regex implementation may reject.
840 * We don't need regex anyway. '' pattern always matches.
841 */
842 if (sp[1] == '}')
843 return 0;
844
845 prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
846 commit_list_insert((struct commit *)o, &list);
847 ret = get_sha1_oneline(prefix, sha1, list);
848 free(prefix);
849 return ret;
850 }
851 return 0;
852}
853
854static int get_describe_name(const char *name, int len, unsigned char *sha1)
855{
856 const char *cp;
857 unsigned flags = GET_SHA1_QUIETLY | GET_SHA1_COMMIT;
858
859 for (cp = name + len - 1; name + 2 <= cp; cp--) {
860 char ch = *cp;
861 if (!isxdigit(ch)) {
862 /* We must be looking at g in "SOMETHING-g"
863 * for it to be describe output.
864 */
865 if (ch == 'g' && cp[-1] == '-') {
866 cp++;
867 len -= cp - name;
868 return get_short_sha1(cp, len, sha1, flags);
869 }
870 }
871 }
872 return -1;
873}
874
875static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags)
876{
877 int ret, has_suffix;
878 const char *cp;
879
880 /*
881 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
882 */
883 has_suffix = 0;
884 for (cp = name + len - 1; name <= cp; cp--) {
885 int ch = *cp;
886 if ('0' <= ch && ch <= '9')
887 continue;
888 if (ch == '~' || ch == '^')
889 has_suffix = ch;
890 break;
891 }
892
893 if (has_suffix) {
894 int num = 0;
895 int len1 = cp - name;
896 cp++;
897 while (cp < name + len)
898 num = num * 10 + *cp++ - '0';
899 if (!num && len1 == len - 1)
900 num = 1;
901 if (has_suffix == '^')
902 return get_parent(name, len1, sha1, num);
903 /* else if (has_suffix == '~') -- goes without saying */
904 return get_nth_ancestor(name, len1, sha1, num);
905 }
906
907 ret = peel_onion(name, len, sha1, lookup_flags);
908 if (!ret)
909 return 0;
910
911 ret = get_sha1_basic(name, len, sha1, lookup_flags);
912 if (!ret)
913 return 0;
914
915 /* It could be describe output that is "SOMETHING-gXXXX" */
916 ret = get_describe_name(name, len, sha1);
917 if (!ret)
918 return 0;
919
920 return get_short_sha1(name, len, sha1, lookup_flags);
921}
922
923/*
924 * This interprets names like ':/Initial revision of "git"' by searching
925 * through history and returning the first commit whose message starts
926 * the given regular expression.
927 *
928 * For negative-matching, prefix the pattern-part with '!-', like: ':/!-WIP'.
929 *
930 * For a literal '!' character at the beginning of a pattern, you have to repeat
931 * that, like: ':/!!foo'
932 *
933 * For future extension, all other sequences beginning with ':/!' are reserved.
934 */
935
936/* Remember to update object flag allocation in object.h */
937#define ONELINE_SEEN (1u<<20)
938
939static int handle_one_ref(const char *path, const struct object_id *oid,
940 int flag, void *cb_data)
941{
942 struct commit_list **list = cb_data;
943 struct object *object = parse_object(oid->hash);
944 if (!object)
945 return 0;
946 if (object->type == OBJ_TAG) {
947 object = deref_tag(object, path, strlen(path));
948 if (!object)
949 return 0;
950 }
951 if (object->type != OBJ_COMMIT)
952 return 0;
953 commit_list_insert((struct commit *)object, list);
954 return 0;
955}
956
957static int get_sha1_oneline(const char *prefix, unsigned char *sha1,
958 struct commit_list *list)
959{
960 struct commit_list *backup = NULL, *l;
961 int found = 0;
962 int negative = 0;
963 regex_t regex;
964
965 if (prefix[0] == '!') {
966 prefix++;
967
968 if (prefix[0] == '-') {
969 prefix++;
970 negative = 1;
971 } else if (prefix[0] != '!') {
972 return -1;
973 }
974 }
975
976 if (regcomp(®ex, prefix, REG_EXTENDED))
977 return -1;
978
979 for (l = list; l; l = l->next) {
980 l->item->object.flags |= ONELINE_SEEN;
981 commit_list_insert(l->item, &backup);
982 }
983 while (list) {
984 const char *p, *buf;
985 struct commit *commit;
986 int matches;
987
988 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
989 if (!parse_object(commit->object.oid.hash))
990 continue;
991 buf = get_commit_buffer(commit, NULL);
992 p = strstr(buf, "\n\n");
993 matches = negative ^ (p && !regexec(®ex, p + 2, 0, NULL, 0));
994 unuse_commit_buffer(commit, buf);
995
996 if (matches) {
997 hashcpy(sha1, commit->object.oid.hash);
998 found = 1;
999 break;
1000 }
1001 }
1002 regfree(®ex);
1003 free_commit_list(list);
1004 for (l = backup; l; l = l->next)
1005 clear_commit_marks(l->item, ONELINE_SEEN);
1006 free_commit_list(backup);
1007 return found ? 0 : -1;
1008}
1009
1010struct grab_nth_branch_switch_cbdata {
1011 int remaining;
1012 struct strbuf buf;
1013};
1014
1015static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
1016 const char *email, unsigned long timestamp, int tz,
1017 const char *message, void *cb_data)
1018{
1019 struct grab_nth_branch_switch_cbdata *cb = cb_data;
1020 const char *match = NULL, *target = NULL;
1021 size_t len;
1022
1023 if (skip_prefix(message, "checkout: moving from ", &match))
1024 target = strstr(match, " to ");
1025
1026 if (!match || !target)
1027 return 0;
1028 if (--(cb->remaining) == 0) {
1029 len = target - match;
1030 strbuf_reset(&cb->buf);
1031 strbuf_add(&cb->buf, match, len);
1032 return 1; /* we are done */
1033 }
1034 return 0;
1035}
1036
1037/*
1038 * Parse @{-N} syntax, return the number of characters parsed
1039 * if successful; otherwise signal an error with negative value.
1040 */
1041static int interpret_nth_prior_checkout(const char *name, int namelen,
1042 struct strbuf *buf)
1043{
1044 long nth;
1045 int retval;
1046 struct grab_nth_branch_switch_cbdata cb;
1047 const char *brace;
1048 char *num_end;
1049
1050 if (namelen < 4)
1051 return -1;
1052 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
1053 return -1;
1054 brace = memchr(name, '}', namelen);
1055 if (!brace)
1056 return -1;
1057 nth = strtol(name + 3, &num_end, 10);
1058 if (num_end != brace)
1059 return -1;
1060 if (nth <= 0)
1061 return -1;
1062 cb.remaining = nth;
1063 strbuf_init(&cb.buf, 20);
1064
1065 retval = 0;
1066 if (0 < for_each_reflog_ent_reverse("HEAD", grab_nth_branch_switch, &cb)) {
1067 strbuf_reset(buf);
1068 strbuf_addbuf(buf, &cb.buf);
1069 retval = brace - name + 1;
1070 }
1071
1072 strbuf_release(&cb.buf);
1073 return retval;
1074}
1075
1076int get_oid_mb(const char *name, struct object_id *oid)
1077{
1078 struct commit *one, *two;
1079 struct commit_list *mbs;
1080 struct object_id oid_tmp;
1081 const char *dots;
1082 int st;
1083
1084 dots = strstr(name, "...");
1085 if (!dots)
1086 return get_oid(name, oid);
1087 if (dots == name)
1088 st = get_oid("HEAD", &oid_tmp);
1089 else {
1090 struct strbuf sb;
1091 strbuf_init(&sb, dots - name);
1092 strbuf_add(&sb, name, dots - name);
1093 st = get_sha1_committish(sb.buf, oid_tmp.hash);
1094 strbuf_release(&sb);
1095 }
1096 if (st)
1097 return st;
1098 one = lookup_commit_reference_gently(oid_tmp.hash, 0);
1099 if (!one)
1100 return -1;
1101
1102 if (get_sha1_committish(dots[3] ? (dots + 3) : "HEAD", oid_tmp.hash))
1103 return -1;
1104 two = lookup_commit_reference_gently(oid_tmp.hash, 0);
1105 if (!two)
1106 return -1;
1107 mbs = get_merge_bases(one, two);
1108 if (!mbs || mbs->next)
1109 st = -1;
1110 else {
1111 st = 0;
1112 oidcpy(oid, &mbs->item->object.oid);
1113 }
1114 free_commit_list(mbs);
1115 return st;
1116}
1117
1118/* parse @something syntax, when 'something' is not {.*} */
1119static int interpret_empty_at(const char *name, int namelen, int len, struct strbuf *buf)
1120{
1121 const char *next;
1122
1123 if (len || name[1] == '{')
1124 return -1;
1125
1126 /* make sure it's a single @, or @@{.*}, not @foo */
1127 next = memchr(name + len + 1, '@', namelen - len - 1);
1128 if (next && next[1] != '{')
1129 return -1;
1130 if (!next)
1131 next = name + namelen;
1132 if (next != name + 1)
1133 return -1;
1134
1135 strbuf_reset(buf);
1136 strbuf_add(buf, "HEAD", 4);
1137 return 1;
1138}
1139
1140static int reinterpret(const char *name, int namelen, int len, struct strbuf *buf)
1141{
1142 /* we have extra data, which might need further processing */
1143 struct strbuf tmp = STRBUF_INIT;
1144 int used = buf->len;
1145 int ret;
1146
1147 strbuf_add(buf, name + len, namelen - len);
1148 ret = interpret_branch_name(buf->buf, buf->len, &tmp);
1149 /* that data was not interpreted, remove our cruft */
1150 if (ret < 0) {
1151 strbuf_setlen(buf, used);
1152 return len;
1153 }
1154 strbuf_reset(buf);
1155 strbuf_addbuf(buf, &tmp);
1156 strbuf_release(&tmp);
1157 /* tweak for size of {-N} versus expanded ref name */
1158 return ret - used + len;
1159}
1160
1161static void set_shortened_ref(struct strbuf *buf, const char *ref)
1162{
1163 char *s = shorten_unambiguous_ref(ref, 0);
1164 strbuf_reset(buf);
1165 strbuf_addstr(buf, s);
1166 free(s);
1167}
1168
1169static int interpret_branch_mark(const char *name, int namelen,
1170 int at, struct strbuf *buf,
1171 int (*get_mark)(const char *, int),
1172 const char *(*get_data)(struct branch *,
1173 struct strbuf *))
1174{
1175 int len;
1176 struct branch *branch;
1177 struct strbuf err = STRBUF_INIT;
1178 const char *value;
1179
1180 len = get_mark(name + at, namelen - at);
1181 if (!len)
1182 return -1;
1183
1184 if (memchr(name, ':', at))
1185 return -1;
1186
1187 if (at) {
1188 char *name_str = xmemdupz(name, at);
1189 branch = branch_get(name_str);
1190 free(name_str);
1191 } else
1192 branch = branch_get(NULL);
1193
1194 value = get_data(branch, &err);
1195 if (!value)
1196 die("%s", err.buf);
1197
1198 set_shortened_ref(buf, value);
1199 return len + at;
1200}
1201
1202/*
1203 * This reads short-hand syntax that not only evaluates to a commit
1204 * object name, but also can act as if the end user spelled the name
1205 * of the branch from the command line.
1206 *
1207 * - "@{-N}" finds the name of the Nth previous branch we were on, and
1208 * places the name of the branch in the given buf and returns the
1209 * number of characters parsed if successful.
1210 *
1211 * - "<branch>@{upstream}" finds the name of the other ref that
1212 * <branch> is configured to merge with (missing <branch> defaults
1213 * to the current branch), and places the name of the branch in the
1214 * given buf and returns the number of characters parsed if
1215 * successful.
1216 *
1217 * If the input is not of the accepted format, it returns a negative
1218 * number to signal an error.
1219 *
1220 * If the input was ok but there are not N branch switches in the
1221 * reflog, it returns 0.
1222 */
1223int interpret_branch_name(const char *name, int namelen, struct strbuf *buf)
1224{
1225 char *at;
1226 const char *start;
1227 int len = interpret_nth_prior_checkout(name, namelen, buf);
1228
1229 if (!namelen)
1230 namelen = strlen(name);
1231
1232 if (!len) {
1233 return len; /* syntax Ok, not enough switches */
1234 } else if (len > 0) {
1235 if (len == namelen)
1236 return len; /* consumed all */
1237 else
1238 return reinterpret(name, namelen, len, buf);
1239 }
1240
1241 for (start = name;
1242 (at = memchr(start, '@', namelen - (start - name)));
1243 start = at + 1) {
1244
1245 len = interpret_empty_at(name, namelen, at - name, buf);
1246 if (len > 0)
1247 return reinterpret(name, namelen, len, buf);
1248
1249 len = interpret_branch_mark(name, namelen, at - name, buf,
1250 upstream_mark, branch_get_upstream);
1251 if (len > 0)
1252 return len;
1253
1254 len = interpret_branch_mark(name, namelen, at - name, buf,
1255 push_mark, branch_get_push);
1256 if (len > 0)
1257 return len;
1258 }
1259
1260 return -1;
1261}
1262
1263int strbuf_branchname(struct strbuf *sb, const char *name)
1264{
1265 int len = strlen(name);
1266 int used = interpret_branch_name(name, len, sb);
1267
1268 if (used == len)
1269 return 0;
1270 if (used < 0)
1271 used = 0;
1272 strbuf_add(sb, name + used, len - used);
1273 return len;
1274}
1275
1276int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
1277{
1278 strbuf_branchname(sb, name);
1279 if (name[0] == '-')
1280 return -1;
1281 strbuf_splice(sb, 0, 0, "refs/heads/", 11);
1282 return check_refname_format(sb->buf, 0);
1283}
1284
1285/*
1286 * This is like "get_sha1_basic()", except it allows "sha1 expressions",
1287 * notably "xyz^" for "parent of xyz"
1288 */
1289int get_sha1(const char *name, unsigned char *sha1)
1290{
1291 struct object_context unused;
1292 return get_sha1_with_context(name, 0, sha1, &unused);
1293}
1294
1295/*
1296 * This is like "get_sha1()", but for struct object_id.
1297 */
1298int get_oid(const char *name, struct object_id *oid)
1299{
1300 return get_sha1(name, oid->hash);
1301}
1302
1303
1304/*
1305 * Many callers know that the user meant to name a commit-ish by
1306 * syntactical positions where the object name appears. Calling this
1307 * function allows the machinery to disambiguate shorter-than-unique
1308 * abbreviated object names between commit-ish and others.
1309 *
1310 * Note that this does NOT error out when the named object is not a
1311 * commit-ish. It is merely to give a hint to the disambiguation
1312 * machinery.
1313 */
1314int get_sha1_committish(const char *name, unsigned char *sha1)
1315{
1316 struct object_context unused;
1317 return get_sha1_with_context(name, GET_SHA1_COMMITTISH,
1318 sha1, &unused);
1319}
1320
1321int get_sha1_treeish(const char *name, unsigned char *sha1)
1322{
1323 struct object_context unused;
1324 return get_sha1_with_context(name, GET_SHA1_TREEISH,
1325 sha1, &unused);
1326}
1327
1328int get_sha1_commit(const char *name, unsigned char *sha1)
1329{
1330 struct object_context unused;
1331 return get_sha1_with_context(name, GET_SHA1_COMMIT,
1332 sha1, &unused);
1333}
1334
1335int get_sha1_tree(const char *name, unsigned char *sha1)
1336{
1337 struct object_context unused;
1338 return get_sha1_with_context(name, GET_SHA1_TREE,
1339 sha1, &unused);
1340}
1341
1342int get_sha1_blob(const char *name, unsigned char *sha1)
1343{
1344 struct object_context unused;
1345 return get_sha1_with_context(name, GET_SHA1_BLOB,
1346 sha1, &unused);
1347}
1348
1349/* Must be called only when object_name:filename doesn't exist. */
1350static void diagnose_invalid_sha1_path(const char *prefix,
1351 const char *filename,
1352 const unsigned char *tree_sha1,
1353 const char *object_name,
1354 int object_name_len)
1355{
1356 unsigned char sha1[20];
1357 unsigned mode;
1358
1359 if (!prefix)
1360 prefix = "";
1361
1362 if (file_exists(filename))
1363 die("Path '%s' exists on disk, but not in '%.*s'.",
1364 filename, object_name_len, object_name);
1365 if (errno == ENOENT || errno == ENOTDIR) {
1366 char *fullname = xstrfmt("%s%s", prefix, filename);
1367
1368 if (!get_tree_entry(tree_sha1, fullname,
1369 sha1, &mode)) {
1370 die("Path '%s' exists, but not '%s'.\n"
1371 "Did you mean '%.*s:%s' aka '%.*s:./%s'?",
1372 fullname,
1373 filename,
1374 object_name_len, object_name,
1375 fullname,
1376 object_name_len, object_name,
1377 filename);
1378 }
1379 die("Path '%s' does not exist in '%.*s'",
1380 filename, object_name_len, object_name);
1381 }
1382}
1383
1384/* Must be called only when :stage:filename doesn't exist. */
1385static void diagnose_invalid_index_path(int stage,
1386 const char *prefix,
1387 const char *filename)
1388{
1389 const struct cache_entry *ce;
1390 int pos;
1391 unsigned namelen = strlen(filename);
1392 struct strbuf fullname = STRBUF_INIT;
1393
1394 if (!prefix)
1395 prefix = "";
1396
1397 /* Wrong stage number? */
1398 pos = cache_name_pos(filename, namelen);
1399 if (pos < 0)
1400 pos = -pos - 1;
1401 if (pos < active_nr) {
1402 ce = active_cache[pos];
1403 if (ce_namelen(ce) == namelen &&
1404 !memcmp(ce->name, filename, namelen))
1405 die("Path '%s' is in the index, but not at stage %d.\n"
1406 "Did you mean ':%d:%s'?",
1407 filename, stage,
1408 ce_stage(ce), filename);
1409 }
1410
1411 /* Confusion between relative and absolute filenames? */
1412 strbuf_addstr(&fullname, prefix);
1413 strbuf_addstr(&fullname, filename);
1414 pos = cache_name_pos(fullname.buf, fullname.len);
1415 if (pos < 0)
1416 pos = -pos - 1;
1417 if (pos < active_nr) {
1418 ce = active_cache[pos];
1419 if (ce_namelen(ce) == fullname.len &&
1420 !memcmp(ce->name, fullname.buf, fullname.len))
1421 die("Path '%s' is in the index, but not '%s'.\n"
1422 "Did you mean ':%d:%s' aka ':%d:./%s'?",
1423 fullname.buf, filename,
1424 ce_stage(ce), fullname.buf,
1425 ce_stage(ce), filename);
1426 }
1427
1428 if (file_exists(filename))
1429 die("Path '%s' exists on disk, but not in the index.", filename);
1430 if (errno == ENOENT || errno == ENOTDIR)
1431 die("Path '%s' does not exist (neither on disk nor in the index).",
1432 filename);
1433
1434 strbuf_release(&fullname);
1435}
1436
1437
1438static char *resolve_relative_path(const char *rel)
1439{
1440 if (!starts_with(rel, "./") && !starts_with(rel, "../"))
1441 return NULL;
1442
1443 if (!is_inside_work_tree())
1444 die("relative path syntax can't be used outside working tree.");
1445
1446 /* die() inside prefix_path() if resolved path is outside worktree */
1447 return prefix_path(startup_info->prefix,
1448 startup_info->prefix ? strlen(startup_info->prefix) : 0,
1449 rel);
1450}
1451
1452static int get_sha1_with_context_1(const char *name,
1453 unsigned flags,
1454 const char *prefix,
1455 unsigned char *sha1,
1456 struct object_context *oc)
1457{
1458 int ret, bracket_depth;
1459 int namelen = strlen(name);
1460 const char *cp;
1461 int only_to_die = flags & GET_SHA1_ONLY_TO_DIE;
1462
1463 if (only_to_die)
1464 flags |= GET_SHA1_QUIETLY;
1465
1466 memset(oc, 0, sizeof(*oc));
1467 oc->mode = S_IFINVALID;
1468 ret = get_sha1_1(name, namelen, sha1, flags);
1469 if (!ret)
1470 return ret;
1471 /*
1472 * sha1:path --> object name of path in ent sha1
1473 * :path -> object name of absolute path in index
1474 * :./path -> object name of path relative to cwd in index
1475 * :[0-3]:path -> object name of path in index at stage
1476 * :/foo -> recent commit matching foo
1477 */
1478 if (name[0] == ':') {
1479 int stage = 0;
1480 const struct cache_entry *ce;
1481 char *new_path = NULL;
1482 int pos;
1483 if (!only_to_die && namelen > 2 && name[1] == '/') {
1484 struct commit_list *list = NULL;
1485
1486 for_each_ref(handle_one_ref, &list);
1487 commit_list_sort_by_date(&list);
1488 return get_sha1_oneline(name + 2, sha1, list);
1489 }
1490 if (namelen < 3 ||
1491 name[2] != ':' ||
1492 name[1] < '0' || '3' < name[1])
1493 cp = name + 1;
1494 else {
1495 stage = name[1] - '0';
1496 cp = name + 3;
1497 }
1498 new_path = resolve_relative_path(cp);
1499 if (!new_path) {
1500 namelen = namelen - (cp - name);
1501 } else {
1502 cp = new_path;
1503 namelen = strlen(cp);
1504 }
1505
1506 strlcpy(oc->path, cp, sizeof(oc->path));
1507
1508 if (!active_cache)
1509 read_cache();
1510 pos = cache_name_pos(cp, namelen);
1511 if (pos < 0)
1512 pos = -pos - 1;
1513 while (pos < active_nr) {
1514 ce = active_cache[pos];
1515 if (ce_namelen(ce) != namelen ||
1516 memcmp(ce->name, cp, namelen))
1517 break;
1518 if (ce_stage(ce) == stage) {
1519 hashcpy(sha1, ce->oid.hash);
1520 oc->mode = ce->ce_mode;
1521 free(new_path);
1522 return 0;
1523 }
1524 pos++;
1525 }
1526 if (only_to_die && name[1] && name[1] != '/')
1527 diagnose_invalid_index_path(stage, prefix, cp);
1528 free(new_path);
1529 return -1;
1530 }
1531 for (cp = name, bracket_depth = 0; *cp; cp++) {
1532 if (*cp == '{')
1533 bracket_depth++;
1534 else if (bracket_depth && *cp == '}')
1535 bracket_depth--;
1536 else if (!bracket_depth && *cp == ':')
1537 break;
1538 }
1539 if (*cp == ':') {
1540 unsigned char tree_sha1[20];
1541 int len = cp - name;
1542 unsigned sub_flags = flags;
1543
1544 sub_flags &= ~GET_SHA1_DISAMBIGUATORS;
1545 sub_flags |= GET_SHA1_TREEISH;
1546
1547 if (!get_sha1_1(name, len, tree_sha1, sub_flags)) {
1548 const char *filename = cp+1;
1549 char *new_filename = NULL;
1550
1551 new_filename = resolve_relative_path(filename);
1552 if (new_filename)
1553 filename = new_filename;
1554 if (flags & GET_SHA1_FOLLOW_SYMLINKS) {
1555 ret = get_tree_entry_follow_symlinks(tree_sha1,
1556 filename, sha1, &oc->symlink_path,
1557 &oc->mode);
1558 } else {
1559 ret = get_tree_entry(tree_sha1, filename,
1560 sha1, &oc->mode);
1561 if (ret && only_to_die) {
1562 diagnose_invalid_sha1_path(prefix,
1563 filename,
1564 tree_sha1,
1565 name, len);
1566 }
1567 }
1568 hashcpy(oc->tree, tree_sha1);
1569 strlcpy(oc->path, filename, sizeof(oc->path));
1570
1571 free(new_filename);
1572 return ret;
1573 } else {
1574 if (only_to_die)
1575 die("Invalid object name '%.*s'.", len, name);
1576 }
1577 }
1578 return ret;
1579}
1580
1581/*
1582 * Call this function when you know "name" given by the end user must
1583 * name an object but it doesn't; the function _may_ die with a better
1584 * diagnostic message than "no such object 'name'", e.g. "Path 'doc' does not
1585 * exist in 'HEAD'" when given "HEAD:doc", or it may return in which case
1586 * you have a chance to diagnose the error further.
1587 */
1588void maybe_die_on_misspelt_object_name(const char *name, const char *prefix)
1589{
1590 struct object_context oc;
1591 unsigned char sha1[20];
1592 get_sha1_with_context_1(name, GET_SHA1_ONLY_TO_DIE, prefix, sha1, &oc);
1593}
1594
1595int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc)
1596{
1597 if (flags & GET_SHA1_FOLLOW_SYMLINKS && flags & GET_SHA1_ONLY_TO_DIE)
1598 die("BUG: incompatible flags for get_sha1_with_context");
1599 return get_sha1_with_context_1(str, flags, NULL, sha1, orc);
1600}