Convert remaining callers of lookup_commit_reference* to object_id
[git/git.git] / sha1_name.c
CommitLineData
9938af6a 1#include "cache.h"
5385f52d 2#include "tag.h"
9938af6a 3#include "commit.h"
5385f52d
JH
4#include "tree.h"
5#include "blob.h"
f3ab49db 6#include "tree-walk.h"
d556fae2 7#include "refs.h"
28fb8438 8#include "remote.h"
dbe44faa 9#include "dir.h"
fad6b9e5 10#include "sha1-array.h"
9938af6a 11
32574b68
NTND
12static int get_sha1_oneline(const char *, unsigned char *, struct commit_list *);
13
d2b7d9c7 14typedef int (*disambiguate_hint_fn)(const struct object_id *, void *);
a78fafe7
JH
15
16struct disambiguate_state {
0016043b 17 int len; /* length of prefix in hex chars */
dc01505f 18 char hex_pfx[GIT_MAX_HEXSZ + 1];
d2ee1185 19 struct object_id bin_pfx;
0016043b 20
a78fafe7
JH
21 disambiguate_hint_fn fn;
22 void *cb_data;
d2ee1185 23 struct object_id candidate;
a78fafe7
JH
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;
957d7406 29 unsigned always_call_fn:1;
a78fafe7
JH
30};
31
d2b7d9c7 32static void update_candidates(struct disambiguate_state *ds, const struct object_id *current)
a78fafe7 33{
957d7406
JH
34 if (ds->always_call_fn) {
35 ds->ambiguous = ds->fn(current, ds->cb_data) ? 1 : 0;
36 return;
37 }
a78fafe7
JH
38 if (!ds->candidate_exists) {
39 /* this is the first candidate */
d2b7d9c7 40 oidcpy(&ds->candidate, current);
a78fafe7
JH
41 ds->candidate_exists = 1;
42 return;
d2b7d9c7 43 } else if (!oidcmp(&ds->candidate, current)) {
a78fafe7
JH
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) {
d2b7d9c7 55 ds->candidate_ok = ds->fn(&ds->candidate, ds->cb_data);
a78fafe7
JH
56 ds->disambiguate_fn_used = 1;
57 ds->candidate_checked = 1;
58 }
59
60 if (!ds->candidate_ok) {
749f763d 61 /* discard the candidate; we know it does not satisfy fn */
d2b7d9c7 62 oidcpy(&ds->candidate, current);
a78fafe7
JH
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
0016043b 80static void find_short_object_filename(struct disambiguate_state *ds)
9938af6a 81{
99a19b43 82 struct alternate_object_database *alt;
dc01505f 83 char hex[GIT_MAX_HEXSZ];
99a19b43
JH
84 static struct alternate_object_database *fakeent;
85
86 if (!fakeent) {
274ac009
JH
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 */
7f0fa2c0 94 fakeent = alloc_alt_odb(get_object_directory());
99a19b43
JH
95 }
96 fakeent->next = alt_odb_list;
9938af6a 97
0016043b 98 xsnprintf(hex, sizeof(hex), "%.2s", ds->hex_pfx);
a78fafe7 99 for (alt = fakeent; alt && !ds->ambiguous; alt = alt->next) {
38dbe5f0 100 struct strbuf *buf = alt_scratch_buf(alt);
9938af6a 101 struct dirent *de;
99a19b43 102 DIR *dir;
597f9134 103
dec04019 104 strbuf_addf(buf, "%.2s/", ds->hex_pfx);
38dbe5f0 105 dir = opendir(buf->buf);
99a19b43
JH
106 if (!dir)
107 continue;
a78fafe7
JH
108
109 while (!ds->ambiguous && (de = readdir(dir)) != NULL) {
d2b7d9c7 110 struct object_id oid;
a78fafe7 111
d2b7d9c7 112 if (strlen(de->d_name) != GIT_SHA1_HEXSZ - 2)
9938af6a 113 continue;
0016043b 114 if (memcmp(de->d_name, ds->hex_pfx + 2, ds->len - 2))
9938af6a 115 continue;
d2b7d9c7 116 memcpy(hex + 2, de->d_name, GIT_SHA1_HEXSZ - 2);
117 if (!get_oid_hex(hex, &oid))
118 update_candidates(ds, &oid);
9938af6a
JH
119 }
120 closedir(dir);
121 }
9938af6a
JH
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
0016043b 139static void unique_in_pack(struct packed_git *p,
a78fafe7 140 struct disambiguate_state *ds)
9938af6a 141{
f703e6ea 142 uint32_t num, last, i, first = 0;
d2b7d9c7 143 const struct object_id *current = NULL;
f703e6ea
JH
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);
d2ee1185 154 cmp = hashcmp(ds->bin_pfx.hash, current);
f703e6ea
JH
155 if (!cmp) {
156 first = mid;
157 break;
9938af6a 158 }
f703e6ea
JH
159 if (cmp > 0) {
160 first = mid+1;
161 continue;
9938af6a 162 }
f703e6ea
JH
163 last = mid;
164 }
165
166 /*
167 * At this point, "first" is the location of the lowest object
1703f9aa 168 * with an object name that could match "bin_pfx". See if we have
f703e6ea
JH
169 * 0, 1 or more objects that actually match(es).
170 */
a78fafe7 171 for (i = first; i < num && !ds->ambiguous; i++) {
d2b7d9c7 172 struct object_id oid;
173 current = nth_packed_object_oid(&oid, p, i);
174 if (!match_sha(ds->len, ds->bin_pfx.hash, current->hash))
f703e6ea 175 break;
a78fafe7 176 update_candidates(ds, current);
9938af6a 177 }
f703e6ea
JH
178}
179
0016043b 180static void find_short_packed_object(struct disambiguate_state *ds)
9938af6a
JH
181{
182 struct packed_git *p;
183
184 prepare_packed_git();
a78fafe7 185 for (p = packed_git; p && !ds->ambiguous; p = p->next)
0016043b 186 unique_in_pack(p, ds);
99a19b43
JH
187}
188
013f276e
JH
189#define SHORT_NAME_NOT_FOUND (-1)
190#define SHORT_NAME_AMBIGUOUS (-2)
191
a78fafe7
JH
192static int finish_object_disambiguation(struct disambiguate_state *ds,
193 unsigned char *sha1)
99a19b43 194{
a78fafe7
JH
195 if (ds->ambiguous)
196 return SHORT_NAME_AMBIGUOUS;
99a19b43 197
a78fafe7 198 if (!ds->candidate_exists)
013f276e 199 return SHORT_NAME_NOT_FOUND;
a78fafe7
JH
200
201 if (!ds->candidate_checked)
202 /*
203 * If this is the only candidate, there is no point
204 * calling the disambiguation hint callback.
205 *
206 * On the other hand, if the current candidate
207 * replaced an earlier candidate that did _not_ pass
208 * the disambiguation hint callback, then we do have
209 * more than one objects that match the short name
210 * given, so we should make sure this one matches;
211 * otherwise, if we discovered this one and the one
212 * that we previously discarded in the reverse order,
213 * we would end up showing different results in the
214 * same repository!
215 */
216 ds->candidate_ok = (!ds->disambiguate_fn_used ||
d2b7d9c7 217 ds->fn(&ds->candidate, ds->cb_data));
a78fafe7
JH
218
219 if (!ds->candidate_ok)
013f276e 220 return SHORT_NAME_AMBIGUOUS;
a78fafe7 221
d2ee1185 222 hashcpy(sha1, ds->candidate.hash);
9938af6a
JH
223 return 0;
224}
225
d2b7d9c7 226static int disambiguate_commit_only(const struct object_id *oid, void *cb_data_unused)
aa1dec9e 227{
d2b7d9c7 228 int kind = sha1_object_info(oid->hash, NULL);
aa1dec9e
JH
229 return kind == OBJ_COMMIT;
230}
231
d2b7d9c7 232static int disambiguate_committish_only(const struct object_id *oid, void *cb_data_unused)
e2643617
JH
233{
234 struct object *obj;
235 int kind;
236
d2b7d9c7 237 kind = sha1_object_info(oid->hash, NULL);
e2643617
JH
238 if (kind == OBJ_COMMIT)
239 return 1;
240 if (kind != OBJ_TAG)
99a19b43 241 return 0;
e2643617
JH
242
243 /* We need to do this the hard way... */
d2b7d9c7 244 obj = deref_tag(parse_object(oid->hash), NULL, 0);
e2643617
JH
245 if (obj && obj->type == OBJ_COMMIT)
246 return 1;
9938af6a
JH
247 return 0;
248}
249
d2b7d9c7 250static int disambiguate_tree_only(const struct object_id *oid, void *cb_data_unused)
9938af6a 251{
d2b7d9c7 252 int kind = sha1_object_info(oid->hash, NULL);
daba53ae
JH
253 return kind == OBJ_TREE;
254}
9938af6a 255
d2b7d9c7 256static int disambiguate_treeish_only(const struct object_id *oid, void *cb_data_unused)
daba53ae
JH
257{
258 struct object *obj;
259 int kind;
260
d2b7d9c7 261 kind = sha1_object_info(oid->hash, NULL);
daba53ae
JH
262 if (kind == OBJ_TREE || kind == OBJ_COMMIT)
263 return 1;
264 if (kind != OBJ_TAG)
265 return 0;
266
267 /* We need to do this the hard way... */
d2b7d9c7 268 obj = deref_tag(parse_object(oid->hash), NULL, 0);
daba53ae
JH
269 if (obj && (obj->type == OBJ_TREE || obj->type == OBJ_COMMIT))
270 return 1;
271 return 0;
272}
273
d2b7d9c7 274static int disambiguate_blob_only(const struct object_id *oid, void *cb_data_unused)
daba53ae 275{
d2b7d9c7 276 int kind = sha1_object_info(oid->hash, NULL);
daba53ae
JH
277 return kind == OBJ_BLOB;
278}
279
5b33cb1f
JK
280static disambiguate_hint_fn default_disambiguate_hint;
281
282int set_disambiguate_hint_config(const char *var, const char *value)
283{
284 static const struct {
285 const char *name;
286 disambiguate_hint_fn fn;
287 } hints[] = {
288 { "none", NULL },
289 { "commit", disambiguate_commit_only },
290 { "committish", disambiguate_committish_only },
291 { "tree", disambiguate_tree_only },
292 { "treeish", disambiguate_treeish_only },
293 { "blob", disambiguate_blob_only }
294 };
295 int i;
296
297 if (!value)
298 return config_error_nonbool(var);
299
300 for (i = 0; i < ARRAY_SIZE(hints); i++) {
301 if (!strcasecmp(value, hints[i].name)) {
302 default_disambiguate_hint = hints[i].fn;
303 return 0;
304 }
305 }
306
307 return error("unknown hint type for '%s': %s", var, value);
308}
309
0016043b
JK
310static int init_object_disambiguation(const char *name, int len,
311 struct disambiguate_state *ds)
9938af6a 312{
957d7406 313 int i;
9938af6a 314
0016043b
JK
315 if (len < MINIMUM_ABBREV || len > GIT_SHA1_HEXSZ)
316 return -1;
317
318 memset(ds, 0, sizeof(*ds));
0016043b 319
af61c6e0 320 for (i = 0; i < len ;i++) {
9938af6a
JH
321 unsigned char c = name[i];
322 unsigned char val;
9938af6a
JH
323 if (c >= '0' && c <= '9')
324 val = c - '0';
325 else if (c >= 'a' && c <= 'f')
326 val = c - 'a' + 10;
327 else if (c >= 'A' && c <='F') {
328 val = c - 'A' + 10;
329 c -= 'A' - 'a';
330 }
331 else
332 return -1;
0016043b 333 ds->hex_pfx[i] = c;
9938af6a
JH
334 if (!(i & 1))
335 val <<= 4;
d2ee1185 336 ds->bin_pfx.hash[i >> 1] |= val;
9938af6a 337 }
0016043b
JK
338
339 ds->len = len;
59e4e34f 340 ds->hex_pfx[len] = '\0';
0016043b 341 prepare_alt_odb();
957d7406
JH
342 return 0;
343}
344
1b7ba794 345static int show_ambiguous_object(const struct object_id *oid, void *data)
1ffa26c4
JK
346{
347 const struct disambiguate_state *ds = data;
348 struct strbuf desc = STRBUF_INIT;
349 int type;
350
d2b7d9c7 351
1b7ba794 352 if (ds->fn && !ds->fn(oid, ds->cb_data))
1ffa26c4
JK
353 return 0;
354
1b7ba794 355 type = sha1_object_info(oid->hash, NULL);
1ffa26c4 356 if (type == OBJ_COMMIT) {
1b7ba794 357 struct commit *commit = lookup_commit(oid->hash);
1ffa26c4
JK
358 if (commit) {
359 struct pretty_print_context pp = {0};
360 pp.date_mode.type = DATE_SHORT;
361 format_commit_message(commit, " %ad - %s", &desc, &pp);
362 }
363 } else if (type == OBJ_TAG) {
1b7ba794 364 struct tag *tag = lookup_tag(oid->hash);
1ffa26c4
JK
365 if (!parse_tag(tag) && tag->tag)
366 strbuf_addf(&desc, " %s", tag->tag);
367 }
368
369 advise(" %s %s%s",
1b7ba794 370 find_unique_abbrev(oid->hash, DEFAULT_ABBREV),
1ffa26c4
JK
371 typename(type) ? typename(type) : "unknown type",
372 desc.buf);
373
374 strbuf_release(&desc);
375 return 0;
376}
377
957d7406
JH
378static int get_short_sha1(const char *name, int len, unsigned char *sha1,
379 unsigned flags)
380{
381 int status;
957d7406
JH
382 struct disambiguate_state ds;
383 int quietly = !!(flags & GET_SHA1_QUIETLY);
384
0016043b 385 if (init_object_disambiguation(name, len, &ds) < 0)
957d7406 386 return -1;
99a19b43 387
259942f5
JK
388 if (HAS_MULTI_BITS(flags & GET_SHA1_DISAMBIGUATORS))
389 die("BUG: multiple get_short_sha1 disambiguator flags");
390
aa1dec9e
JH
391 if (flags & GET_SHA1_COMMIT)
392 ds.fn = disambiguate_commit_only;
e2643617
JH
393 else if (flags & GET_SHA1_COMMITTISH)
394 ds.fn = disambiguate_committish_only;
daba53ae
JH
395 else if (flags & GET_SHA1_TREE)
396 ds.fn = disambiguate_tree_only;
397 else if (flags & GET_SHA1_TREEISH)
398 ds.fn = disambiguate_treeish_only;
399 else if (flags & GET_SHA1_BLOB)
400 ds.fn = disambiguate_blob_only;
5b33cb1f
JK
401 else
402 ds.fn = default_disambiguate_hint;
aa1dec9e 403
0016043b
JK
404 find_short_object_filename(&ds);
405 find_short_packed_object(&ds);
a78fafe7 406 status = finish_object_disambiguation(&ds, sha1);
99a19b43 407
1ffa26c4
JK
408 if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) {
409 error(_("short SHA1 %s is ambiguous"), ds.hex_pfx);
410
411 /*
412 * We may still have ambiguity if we simply saw a series of
413 * candidates that did not satisfy our hint function. In
414 * that case, we still want to show them, so disable the hint
415 * function entirely.
416 */
417 if (!ds.ambiguous)
418 ds.fn = NULL;
419
420 advise(_("The candidates are:"));
421 for_each_abbrev(ds.hex_pfx, show_ambiguous_object, &ds);
422 }
423
013f276e
JH
424 return status;
425}
426
d2b7d9c7 427static int collect_ambiguous(const struct object_id *oid, void *data)
fad6b9e5 428{
910650d2 429 oid_array_append(data, oid);
fad6b9e5
JK
430 return 0;
431}
432
957d7406
JH
433int for_each_abbrev(const char *prefix, each_abbrev_fn fn, void *cb_data)
434{
910650d2 435 struct oid_array collect = OID_ARRAY_INIT;
957d7406 436 struct disambiguate_state ds;
fad6b9e5 437 int ret;
957d7406 438
0016043b 439 if (init_object_disambiguation(prefix, strlen(prefix), &ds) < 0)
957d7406 440 return -1;
957d7406 441
957d7406 442 ds.always_call_fn = 1;
fad6b9e5
JK
443 ds.fn = collect_ambiguous;
444 ds.cb_data = &collect;
0016043b
JK
445 find_short_object_filename(&ds);
446 find_short_packed_object(&ds);
fad6b9e5 447
910650d2 448 ret = oid_array_for_each_unique(&collect, fn, cb_data);
449 oid_array_clear(&collect);
fad6b9e5 450 return ret;
957d7406
JH
451}
452
8e3f52d7
JK
453/*
454 * Return the slot of the most-significant bit set in "val". There are various
455 * ways to do this quickly with fls() or __builtin_clzl(), but speed is
456 * probably not a big deal here.
457 */
458static unsigned msb(unsigned long val)
459{
460 unsigned r = 0;
461 while (val >>= 1)
462 r++;
463 return r;
464}
465
af49c6d0 466int find_unique_abbrev_r(char *hex, const unsigned char *sha1, int len)
013f276e 467{
b66fde9a 468 int status, exists;
47dd0d59 469
e6c587c7 470 if (len < 0) {
8e3f52d7
JK
471 unsigned long count = approximate_object_count();
472 /*
473 * Add one because the MSB only tells us the highest bit set,
474 * not including the value of all the _other_ bits (so "15"
475 * is only one off of 2^4, but the MSB is the 3rd bit.
476 */
477 len = msb(count) + 1;
478 /*
479 * We now know we have on the order of 2^len objects, which
480 * expects a collision at 2^(len/2). But we also care about hex
481 * chars, not bits, and there are 4 bits per hex. So all
482 * together we need to divide by 2; but we also want to round
483 * odd numbers up, hence adding one before dividing.
484 */
485 len = (len + 1) / 2;
486 /*
487 * For very small repos, we stick with our regular fallback.
488 */
489 if (len < FALLBACK_DEFAULT_ABBREV)
490 len = FALLBACK_DEFAULT_ABBREV;
e6c587c7 491 }
8e3f52d7 492
af49c6d0 493 sha1_to_hex_r(hex, sha1);
02c5cba2 494 if (len == 40 || !len)
af49c6d0 495 return 40;
61e704e3 496 exists = has_sha1_file(sha1);
013f276e
JH
497 while (len < 40) {
498 unsigned char sha1_ret[20];
8e3f52d7 499 status = get_short_sha1(hex, len, sha1_ret, GET_SHA1_QUIETLY);
b66fde9a
JH
500 if (exists
501 ? !status
502 : status == SHORT_NAME_NOT_FOUND) {
ea2c69ed 503 hex[len] = 0;
af49c6d0 504 return len;
013f276e 505 }
013f276e
JH
506 len++;
507 }
af49c6d0
JK
508 return len;
509}
510
511const char *find_unique_abbrev(const unsigned char *sha1, int len)
512{
ef2ed501 513 static int bufno;
dc01505f 514 static char hexbuffer[4][GIT_MAX_HEXSZ + 1];
3e98919a
RS
515 char *hex = hexbuffer[bufno];
516 bufno = (bufno + 1) % ARRAY_SIZE(hexbuffer);
af49c6d0 517 find_unique_abbrev_r(hex, sha1, len);
b66fde9a 518 return hex;
9938af6a
JH
519}
520
6677c466 521static int ambiguous_path(const char *path, int len)
af13cdf2
LT
522{
523 int slash = 1;
6677c466 524 int cnt;
af13cdf2 525
6677c466 526 for (cnt = 0; cnt < len; cnt++) {
af13cdf2
LT
527 switch (*path++) {
528 case '\0':
529 break;
530 case '/':
531 if (slash)
532 break;
533 slash = 1;
534 continue;
535 case '.':
536 continue;
537 default:
538 slash = 0;
539 continue;
540 }
c054d64e 541 break;
af13cdf2 542 }
6677c466 543 return slash;
af13cdf2
LT
544}
545
a1ad0eb0
JK
546static inline int at_mark(const char *string, int len,
547 const char **suffix, int nr)
ae0ba8e2 548{
ae0ba8e2
JH
549 int i;
550
a1ad0eb0 551 for (i = 0; i < nr; i++) {
ae0ba8e2
JH
552 int suffix_len = strlen(suffix[i]);
553 if (suffix_len <= len
244ea1b5 554 && !strncasecmp(string, suffix[i], suffix_len))
ae0ba8e2
JH
555 return suffix_len;
556 }
557 return 0;
558}
559
a1ad0eb0
JK
560static inline int upstream_mark(const char *string, int len)
561{
562 const char *suffix[] = { "@{upstream}", "@{u}" };
563 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
564}
565
adfe5d04
JK
566static inline int push_mark(const char *string, int len)
567{
568 const char *suffix[] = { "@{push}" };
569 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
570}
571
e48ba200 572static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags);
8cd4249c 573static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
d18ba221 574
c41a87dd
DA
575static int get_sha1_basic(const char *str, int len, unsigned char *sha1,
576 unsigned int flags)
e86eb666 577{
eedce784 578 static const char *warn_msg = "refname '%.*s' is ambiguous.";
798c35fc
NTND
579 static const char *object_name_msg = N_(
580 "Git normally never creates a ref that ends with 40 hex characters\n"
581 "because it will be ignored when you just specify 40-hex. These refs\n"
582 "may be created by mistake. For example,\n"
583 "\n"
584 " git checkout -b $br $(git rev-parse ...)\n"
585 "\n"
586 "where \"$br\" is somehow empty and a 40-hex ref is created. Please\n"
587 "examine these refs and maybe delete them. Turn this message off by\n"
8dc84fdc 588 "running \"git config advice.objectNameWarning false\"");
798c35fc 589 unsigned char tmp_sha1[20];
ed378ec7 590 char *real_ref = NULL;
ab2a1a32 591 int refs_found = 0;
128fd54d 592 int at, reflog_len, nth_prior = 0;
9938af6a 593
798c35fc 594 if (len == 40 && !get_sha1_hex(str, sha1)) {
832cf74c 595 if (warn_ambiguous_refs && warn_on_object_refname_ambiguity) {
25fba78d 596 refs_found = dwim_ref(str, len, tmp_sha1, &real_ref);
832cf74c 597 if (refs_found > 0) {
25fba78d
JK
598 warning(warn_msg, len, str);
599 if (advice_object_name_warning)
600 fprintf(stderr, "%s\n", _(object_name_msg));
601 }
602 free(real_ref);
798c35fc 603 }
9938af6a 604 return 0;
798c35fc 605 }
9938af6a 606
d18ba221 607 /* basic@{time or number or -number} format to query ref-log */
694500ed 608 reflog_len = at = 0;
f265458f 609 if (len && str[len-1] == '}') {
e883a057 610 for (at = len-4; at >= 0; at--) {
ab2a1a32 611 if (str[at] == '@' && str[at+1] == '{') {
83d16bc7
RR
612 if (str[at+2] == '-') {
613 if (at != 0)
614 /* @{-N} not at start */
615 return -1;
128fd54d
FC
616 nth_prior = 1;
617 continue;
618 }
adfe5d04
JK
619 if (!upstream_mark(str + at, len - at) &&
620 !push_mark(str + at, len - at)) {
28fb8438
JS
621 reflog_len = (len-1) - (at+2);
622 len = at;
623 }
ab2a1a32
JH
624 break;
625 }
d556fae2
SP
626 }
627 }
628
af13cdf2 629 /* Accept only unambiguous ref paths. */
11cf8801 630 if (len && ambiguous_path(str, len))
af13cdf2
LT
631 return -1;
632
128fd54d 633 if (nth_prior) {
d18ba221 634 struct strbuf buf = STRBUF_INIT;
128fd54d
FC
635 int detached;
636
8cd4249c 637 if (interpret_nth_prior_checkout(str, len, &buf) > 0) {
128fd54d
FC
638 detached = (buf.len == 40 && !get_sha1_hex(buf.buf, sha1));
639 strbuf_release(&buf);
640 if (detached)
641 return 0;
d18ba221 642 }
128fd54d
FC
643 }
644
645 if (!len && reflog_len)
11cf8801
NP
646 /* allow "@{...}" to mean the current branch reflog */
647 refs_found = dwim_ref("HEAD", 4, sha1, &real_ref);
128fd54d 648 else if (reflog_len)
f2eba66d
NP
649 refs_found = dwim_log(str, len, sha1, &real_ref);
650 else
11cf8801 651 refs_found = dwim_ref(str, len, sha1, &real_ref);
d556fae2
SP
652
653 if (!refs_found)
654 return -1;
655
c41a87dd 656 if (warn_ambiguous_refs && !(flags & GET_SHA1_QUIETLY) &&
798c35fc
NTND
657 (refs_found > 1 ||
658 !get_short_sha1(str, len, tmp_sha1, GET_SHA1_QUIETLY)))
eedce784 659 warning(warn_msg, len, str);
d556fae2 660
ab2a1a32 661 if (reflog_len) {
ab2a1a32
JH
662 int nth, i;
663 unsigned long at_time;
16d7cc90
JH
664 unsigned long co_time;
665 int co_tz, co_cnt;
666
fe558516 667 /* Is it asking for N-th entry, or approxidate? */
ab2a1a32
JH
668 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
669 char ch = str[at+2+i];
670 if ('0' <= ch && ch <= '9')
671 nth = nth * 10 + ch - '0';
672 else
673 nth = -1;
674 }
ea360dd0
SP
675 if (100000000 <= nth) {
676 at_time = nth;
677 nth = -1;
678 } else if (0 <= nth)
ab2a1a32 679 at_time = 0;
861f00e3 680 else {
93cfa7c7 681 int errors = 0;
861f00e3 682 char *tmp = xstrndup(str + at + 2, reflog_len);
93cfa7c7 683 at_time = approxidate_careful(tmp, &errors);
861f00e3 684 free(tmp);
28b35632
JK
685 if (errors) {
686 free(real_ref);
a5e10acb 687 return -1;
28b35632 688 }
861f00e3 689 }
c41a87dd 690 if (read_ref_at(real_ref, flags, at_time, nth, sha1, NULL,
16d7cc90 691 &co_time, &co_tz, &co_cnt)) {
305ebea0 692 if (!len) {
59556548 693 if (starts_with(real_ref, "refs/heads/")) {
305ebea0
RR
694 str = real_ref + 11;
695 len = strlen(real_ref + 11);
696 } else {
697 /* detached HEAD */
698 str = "HEAD";
699 len = 4;
700 }
701 }
c41a87dd
DA
702 if (at_time) {
703 if (!(flags & GET_SHA1_QUIETLY)) {
704 warning("Log for '%.*s' only goes "
705 "back to %s.", len, str,
a5481a6c 706 show_date(co_time, co_tz, DATE_MODE(RFC2822)));
c41a87dd
DA
707 }
708 } else {
709 if (flags & GET_SHA1_QUIETLY) {
710 exit(128);
711 }
e6eedc31
JS
712 die("Log for '%.*s' only has %d entries.",
713 len, str, co_cnt);
714 }
16d7cc90 715 }
d556fae2
SP
716 }
717
ed378ec7 718 free(real_ref);
d556fae2 719 return 0;
9938af6a
JH
720}
721
9938af6a
JH
722static int get_parent(const char *name, int len,
723 unsigned char *result, int idx)
724{
1e43ed98 725 struct object_id oid;
726 int ret = get_sha1_1(name, len, oid.hash, GET_SHA1_COMMITTISH);
9938af6a
JH
727 struct commit *commit;
728 struct commit_list *p;
729
730 if (ret)
731 return ret;
1e43ed98 732 commit = lookup_commit_reference(oid.hash);
9938af6a
JH
733 if (parse_commit(commit))
734 return -1;
735 if (!idx) {
ed1c9977 736 hashcpy(result, commit->object.oid.hash);
9938af6a
JH
737 return 0;
738 }
739 p = commit->parents;
740 while (p) {
741 if (!--idx) {
ed1c9977 742 hashcpy(result, p->item->object.oid.hash);
9938af6a
JH
743 return 0;
744 }
745 p = p->next;
746 }
747 return -1;
748}
749
4f7599ac
JH
750static int get_nth_ancestor(const char *name, int len,
751 unsigned char *result, int generation)
752{
1e43ed98 753 struct object_id oid;
621ff675
LT
754 struct commit *commit;
755 int ret;
756
1e43ed98 757 ret = get_sha1_1(name, len, oid.hash, GET_SHA1_COMMITTISH);
4f7599ac
JH
758 if (ret)
759 return ret;
1e43ed98 760 commit = lookup_commit_reference(oid.hash);
621ff675
LT
761 if (!commit)
762 return -1;
4f7599ac
JH
763
764 while (generation--) {
621ff675 765 if (parse_commit(commit) || !commit->parents)
4f7599ac 766 return -1;
621ff675 767 commit = commit->parents->item;
4f7599ac 768 }
ed1c9977 769 hashcpy(result, commit->object.oid.hash);
4f7599ac
JH
770 return 0;
771}
772
81776315
JH
773struct object *peel_to_type(const char *name, int namelen,
774 struct object *o, enum object_type expected_type)
775{
776 if (name && !namelen)
777 namelen = strlen(name);
81776315 778 while (1) {
ed1c9977 779 if (!o || (!o->parsed && !parse_object(o->oid.hash)))
81776315 780 return NULL;
a6a3f2cc 781 if (expected_type == OBJ_ANY || o->type == expected_type)
81776315
JH
782 return o;
783 if (o->type == OBJ_TAG)
784 o = ((struct tag*) o)->tagged;
785 else if (o->type == OBJ_COMMIT)
786 o = &(((struct commit *) o)->tree->object);
787 else {
788 if (name)
789 error("%.*s: expected %s type, but the object "
790 "dereferences to %s type",
791 namelen, name, typename(expected_type),
792 typename(o->type));
793 return NULL;
794 }
795 }
796}
797
8a10fea4
JK
798static int peel_onion(const char *name, int len, unsigned char *sha1,
799 unsigned lookup_flags)
5385f52d
JH
800{
801 unsigned char outer[20];
802 const char *sp;
885a86ab 803 unsigned int expected_type = 0;
5385f52d
JH
804 struct object *o;
805
806 /*
807 * "ref^{type}" dereferences ref repeatedly until you cannot
808 * dereference anymore, or you get an object of given type,
809 * whichever comes first. "ref^{}" means just dereference
810 * tags until you get a non-tag. "ref^0" is a shorthand for
811 * "ref^{commit}". "commit^{tree}" could be used to find the
812 * top-level tree of the given commit.
813 */
814 if (len < 4 || name[len-1] != '}')
815 return -1;
816
817 for (sp = name + len - 1; name <= sp; sp--) {
818 int ch = *sp;
819 if (ch == '{' && name < sp && sp[-1] == '^')
820 break;
821 }
822 if (sp <= name)
823 return -1;
824
825 sp++; /* beginning of type name, or closing brace for empty */
59556548 826 if (starts_with(sp, "commit}"))
1974632c 827 expected_type = OBJ_COMMIT;
59556548 828 else if (starts_with(sp, "tag}"))
75aa26d3 829 expected_type = OBJ_TAG;
59556548 830 else if (starts_with(sp, "tree}"))
1974632c 831 expected_type = OBJ_TREE;
59556548 832 else if (starts_with(sp, "blob}"))
1974632c 833 expected_type = OBJ_BLOB;
59556548 834 else if (starts_with(sp, "object}"))
a6a3f2cc 835 expected_type = OBJ_ANY;
5385f52d 836 else if (sp[0] == '}')
1974632c 837 expected_type = OBJ_NONE;
32574b68
NTND
838 else if (sp[0] == '/')
839 expected_type = OBJ_COMMIT;
5385f52d
JH
840 else
841 return -1;
842
8a10fea4 843 lookup_flags &= ~GET_SHA1_DISAMBIGUATORS;
e2643617 844 if (expected_type == OBJ_COMMIT)
8a10fea4 845 lookup_flags |= GET_SHA1_COMMITTISH;
ed1ca602 846 else if (expected_type == OBJ_TREE)
8a10fea4 847 lookup_flags |= GET_SHA1_TREEISH;
e2643617
JH
848
849 if (get_sha1_1(name, sp - name - 2, outer, lookup_flags))
5385f52d
JH
850 return -1;
851
852 o = parse_object(outer);
853 if (!o)
854 return -1;
885a86ab 855 if (!expected_type) {
9534f40b 856 o = deref_tag(o, name, sp - name - 2);
ed1c9977 857 if (!o || (!o->parsed && !parse_object(o->oid.hash)))
6e1c6c10 858 return -1;
f2fd0760 859 hashcpy(sha1, o->oid.hash);
32574b68 860 return 0;
5385f52d 861 }
32574b68
NTND
862
863 /*
864 * At this point, the syntax look correct, so
865 * if we do not get the needed object, we should
866 * barf.
867 */
868 o = peel_to_type(name, len, o, expected_type);
869 if (!o)
81776315 870 return -1;
32574b68 871
ed1c9977 872 hashcpy(sha1, o->oid.hash);
32574b68
NTND
873 if (sp[0] == '/') {
874 /* "$commit^{/foo}" */
875 char *prefix;
876 int ret;
877 struct commit_list *list = NULL;
878
81776315 879 /*
4322842a
NTND
880 * $commit^{/}. Some regex implementation may reject.
881 * We don't need regex anyway. '' pattern always matches.
5385f52d 882 */
4322842a 883 if (sp[1] == '}')
81776315 884 return 0;
4322842a 885
32574b68
NTND
886 prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
887 commit_list_insert((struct commit *)o, &list);
888 ret = get_sha1_oneline(prefix, sha1, list);
889 free(prefix);
890 return ret;
5385f52d
JH
891 }
892 return 0;
893}
894
7dd45e15
JH
895static int get_describe_name(const char *name, int len, unsigned char *sha1)
896{
897 const char *cp;
6269b6b6 898 unsigned flags = GET_SHA1_QUIETLY | GET_SHA1_COMMIT;
7dd45e15
JH
899
900 for (cp = name + len - 1; name + 2 <= cp; cp--) {
901 char ch = *cp;
6f75d45b 902 if (!isxdigit(ch)) {
7dd45e15
JH
903 /* We must be looking at g in "SOMETHING-g"
904 * for it to be describe output.
905 */
906 if (ch == 'g' && cp[-1] == '-') {
907 cp++;
908 len -= cp - name;
6269b6b6 909 return get_short_sha1(cp, len, sha1, flags);
7dd45e15
JH
910 }
911 }
912 }
913 return -1;
914}
915
e48ba200 916static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags)
9938af6a 917{
0601dbe1 918 int ret, has_suffix;
4f7599ac 919 const char *cp;
9938af6a 920
621ff675
LT
921 /*
922 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
4f7599ac 923 */
0601dbe1 924 has_suffix = 0;
4f7599ac
JH
925 for (cp = name + len - 1; name <= cp; cp--) {
926 int ch = *cp;
927 if ('0' <= ch && ch <= '9')
928 continue;
0601dbe1
JH
929 if (ch == '~' || ch == '^')
930 has_suffix = ch;
4f7599ac
JH
931 break;
932 }
0601dbe1
JH
933
934 if (has_suffix) {
935 int num = 0;
4f7599ac
JH
936 int len1 = cp - name;
937 cp++;
938 while (cp < name + len)
0601dbe1 939 num = num * 10 + *cp++ - '0';
621ff675
LT
940 if (!num && len1 == len - 1)
941 num = 1;
942 if (has_suffix == '^')
0601dbe1 943 return get_parent(name, len1, sha1, num);
0601dbe1
JH
944 /* else if (has_suffix == '~') -- goes without saying */
945 return get_nth_ancestor(name, len1, sha1, num);
4f7599ac
JH
946 }
947
8a10fea4 948 ret = peel_onion(name, len, sha1, lookup_flags);
5385f52d
JH
949 if (!ret)
950 return 0;
951
c41a87dd 952 ret = get_sha1_basic(name, len, sha1, lookup_flags);
9938af6a
JH
953 if (!ret)
954 return 0;
7dd45e15
JH
955
956 /* It could be describe output that is "SOMETHING-gXXXX" */
957 ret = get_describe_name(name, len, sha1);
958 if (!ret)
959 return 0;
960
e2643617 961 return get_short_sha1(name, len, sha1, lookup_flags);
9938af6a
JH
962}
963
f7bff003
JH
964/*
965 * This interprets names like ':/Initial revision of "git"' by searching
966 * through history and returning the first commit whose message starts
3d045897 967 * the given regular expression.
f7bff003 968 *
0769854f
WP
969 * For negative-matching, prefix the pattern-part with '!-', like: ':/!-WIP'.
970 *
971 * For a literal '!' character at the beginning of a pattern, you have to repeat
972 * that, like: ':/!!foo'
973 *
974 * For future extension, all other sequences beginning with ':/!' are reserved.
f7bff003 975 */
208acbfb
NTND
976
977/* Remember to update object flag allocation in object.h */
f7bff003
JH
978#define ONELINE_SEEN (1u<<20)
979
9c5fe0b8
MH
980static int handle_one_ref(const char *path, const struct object_id *oid,
981 int flag, void *cb_data)
28a4d940
JS
982{
983 struct commit_list **list = cb_data;
9c5fe0b8 984 struct object *object = parse_object(oid->hash);
28a4d940
JS
985 if (!object)
986 return 0;
affeef12 987 if (object->type == OBJ_TAG) {
28a4d940 988 object = deref_tag(object, path, strlen(path));
affeef12
MK
989 if (!object)
990 return 0;
991 }
28a4d940
JS
992 if (object->type != OBJ_COMMIT)
993 return 0;
e8d1dfe6 994 commit_list_insert((struct commit *)object, list);
28a4d940
JS
995 return 0;
996}
997
84baa31b
NTND
998static int get_sha1_oneline(const char *prefix, unsigned char *sha1,
999 struct commit_list *list)
28a4d940 1000{
84baa31b 1001 struct commit_list *backup = NULL, *l;
28042dbc 1002 int found = 0;
0769854f 1003 int negative = 0;
57895105 1004 regex_t regex;
28a4d940
JS
1005
1006 if (prefix[0] == '!') {
28a4d940 1007 prefix++;
0769854f
WP
1008
1009 if (prefix[0] == '-') {
1010 prefix++;
1011 negative = 1;
1012 } else if (prefix[0] != '!') {
e6a6a768 1013 return -1;
0769854f 1014 }
28a4d940 1015 }
57895105
LT
1016
1017 if (regcomp(&regex, prefix, REG_EXTENDED))
aac4fac1 1018 return -1;
57895105 1019
84baa31b
NTND
1020 for (l = list; l; l = l->next) {
1021 l->item->object.flags |= ONELINE_SEEN;
28a4d940 1022 commit_list_insert(l->item, &backup);
84baa31b 1023 }
ed8ad7e2 1024 while (list) {
ba41c1c9 1025 const char *p, *buf;
1358e7d6 1026 struct commit *commit;
28042dbc 1027 int matches;
ed8ad7e2
JM
1028
1029 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
ed1c9977 1030 if (!parse_object(commit->object.oid.hash))
283cdbcf 1031 continue;
8597ea3a 1032 buf = get_commit_buffer(commit, NULL);
ba41c1c9 1033 p = strstr(buf, "\n\n");
0769854f 1034 matches = negative ^ (p && !regexec(&regex, p + 2, 0, NULL, 0));
ba41c1c9 1035 unuse_commit_buffer(commit, buf);
28042dbc
JH
1036
1037 if (matches) {
ed1c9977 1038 hashcpy(sha1, commit->object.oid.hash);
28042dbc 1039 found = 1;
28a4d940
JS
1040 break;
1041 }
1042 }
57895105 1043 regfree(&regex);
28a4d940
JS
1044 free_commit_list(list);
1045 for (l = backup; l; l = l->next)
1046 clear_commit_marks(l->item, ONELINE_SEEN);
28042dbc
JH
1047 free_commit_list(backup);
1048 return found ? 0 : -1;
28a4d940
JS
1049}
1050
ae5a6c36 1051struct grab_nth_branch_switch_cbdata {
98f85ff4
JH
1052 int remaining;
1053 struct strbuf buf;
ae5a6c36
JH
1054};
1055
9461d272 1056static int grab_nth_branch_switch(struct object_id *ooid, struct object_id *noid,
ae5a6c36
JH
1057 const char *email, unsigned long timestamp, int tz,
1058 const char *message, void *cb_data)
1059{
1060 struct grab_nth_branch_switch_cbdata *cb = cb_data;
a884d0cb
TR
1061 const char *match = NULL, *target = NULL;
1062 size_t len;
1063
95b567c7 1064 if (skip_prefix(message, "checkout: moving from ", &match))
d7c03c1f 1065 target = strstr(match, " to ");
ae5a6c36 1066
c829774c 1067 if (!match || !target)
ae5a6c36 1068 return 0;
98f85ff4
JH
1069 if (--(cb->remaining) == 0) {
1070 len = target - match;
1071 strbuf_reset(&cb->buf);
1072 strbuf_add(&cb->buf, match, len);
1073 return 1; /* we are done */
1074 }
ae5a6c36
JH
1075 return 0;
1076}
1077
1078/*
ae0ba8e2
JH
1079 * Parse @{-N} syntax, return the number of characters parsed
1080 * if successful; otherwise signal an error with negative value.
ae5a6c36 1081 */
8cd4249c
JK
1082static int interpret_nth_prior_checkout(const char *name, int namelen,
1083 struct strbuf *buf)
ae5a6c36 1084{
c2883e62 1085 long nth;
98f85ff4 1086 int retval;
ae5a6c36 1087 struct grab_nth_branch_switch_cbdata cb;
a884d0cb
TR
1088 const char *brace;
1089 char *num_end;
ae5a6c36 1090
8cd4249c
JK
1091 if (namelen < 4)
1092 return -1;
ae5a6c36
JH
1093 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
1094 return -1;
8cd4249c 1095 brace = memchr(name, '}', namelen);
a884d0cb
TR
1096 if (!brace)
1097 return -1;
98f85ff4 1098 nth = strtol(name + 3, &num_end, 10);
a884d0cb 1099 if (num_end != brace)
ae5a6c36 1100 return -1;
c2883e62
JH
1101 if (nth <= 0)
1102 return -1;
98f85ff4
JH
1103 cb.remaining = nth;
1104 strbuf_init(&cb.buf, 20);
1105
39765e59 1106 retval = 0;
98f85ff4
JH
1107 if (0 < for_each_reflog_ent_reverse("HEAD", grab_nth_branch_switch, &cb)) {
1108 strbuf_reset(buf);
e992d1eb 1109 strbuf_addbuf(buf, &cb.buf);
98f85ff4
JH
1110 retval = brace - name + 1;
1111 }
a884d0cb 1112
98f85ff4 1113 strbuf_release(&cb.buf);
39765e59 1114 return retval;
ae5a6c36
JH
1115}
1116
151b2911 1117int get_oid_mb(const char *name, struct object_id *oid)
619a644d
JH
1118{
1119 struct commit *one, *two;
1120 struct commit_list *mbs;
151b2911 1121 struct object_id oid_tmp;
619a644d
JH
1122 const char *dots;
1123 int st;
1124
1125 dots = strstr(name, "...");
1126 if (!dots)
151b2911 1127 return get_oid(name, oid);
619a644d 1128 if (dots == name)
151b2911 1129 st = get_oid("HEAD", &oid_tmp);
619a644d
JH
1130 else {
1131 struct strbuf sb;
1132 strbuf_init(&sb, dots - name);
1133 strbuf_add(&sb, name, dots - name);
151b2911 1134 st = get_sha1_committish(sb.buf, oid_tmp.hash);
619a644d
JH
1135 strbuf_release(&sb);
1136 }
1137 if (st)
1138 return st;
151b2911 1139 one = lookup_commit_reference_gently(oid_tmp.hash, 0);
619a644d
JH
1140 if (!one)
1141 return -1;
1142
151b2911 1143 if (get_sha1_committish(dots[3] ? (dots + 3) : "HEAD", oid_tmp.hash))
619a644d 1144 return -1;
151b2911 1145 two = lookup_commit_reference_gently(oid_tmp.hash, 0);
619a644d
JH
1146 if (!two)
1147 return -1;
2ce406cc 1148 mbs = get_merge_bases(one, two);
619a644d
JH
1149 if (!mbs || mbs->next)
1150 st = -1;
1151 else {
1152 st = 0;
151b2911 1153 oidcpy(oid, &mbs->item->object.oid);
619a644d
JH
1154 }
1155 free_commit_list(mbs);
1156 return st;
1157}
1158
9ba89f48
FC
1159/* parse @something syntax, when 'something' is not {.*} */
1160static int interpret_empty_at(const char *name, int namelen, int len, struct strbuf *buf)
1161{
1162 const char *next;
1163
1164 if (len || name[1] == '{')
1165 return -1;
1166
1167 /* make sure it's a single @, or @@{.*}, not @foo */
8cd4249c 1168 next = memchr(name + len + 1, '@', namelen - len - 1);
9ba89f48
FC
1169 if (next && next[1] != '{')
1170 return -1;
1171 if (!next)
1172 next = name + namelen;
1173 if (next != name + 1)
1174 return -1;
1175
1176 strbuf_reset(buf);
1177 strbuf_add(buf, "HEAD", 4);
1178 return 1;
1179}
1180
0e9f62da
JK
1181static int reinterpret(const char *name, int namelen, int len,
1182 struct strbuf *buf, unsigned allowed)
7a0a49a7
FC
1183{
1184 /* we have extra data, which might need further processing */
1185 struct strbuf tmp = STRBUF_INIT;
1186 int used = buf->len;
1187 int ret;
1188
1189 strbuf_add(buf, name + len, namelen - len);
0e9f62da 1190 ret = interpret_branch_name(buf->buf, buf->len, &tmp, allowed);
7a0a49a7
FC
1191 /* that data was not interpreted, remove our cruft */
1192 if (ret < 0) {
1193 strbuf_setlen(buf, used);
1194 return len;
1195 }
1196 strbuf_reset(buf);
1197 strbuf_addbuf(buf, &tmp);
1198 strbuf_release(&tmp);
1199 /* tweak for size of {-N} versus expanded ref name */
1200 return ret - used + len;
1201}
1202
a39c14af
JK
1203static void set_shortened_ref(struct strbuf *buf, const char *ref)
1204{
1205 char *s = shorten_unambiguous_ref(ref, 0);
1206 strbuf_reset(buf);
1207 strbuf_addstr(buf, s);
1208 free(s);
1209}
1210
0e9f62da
JK
1211static int branch_interpret_allowed(const char *refname, unsigned allowed)
1212{
1213 if (!allowed)
1214 return 1;
1215
1216 if ((allowed & INTERPRET_BRANCH_LOCAL) &&
1217 starts_with(refname, "refs/heads/"))
1218 return 1;
1219 if ((allowed & INTERPRET_BRANCH_REMOTE) &&
1220 starts_with(refname, "refs/remotes/"))
1221 return 1;
1222
1223 return 0;
1224}
1225
48c58471
JK
1226static int interpret_branch_mark(const char *name, int namelen,
1227 int at, struct strbuf *buf,
1228 int (*get_mark)(const char *, int),
1229 const char *(*get_data)(struct branch *,
0e9f62da
JK
1230 struct strbuf *),
1231 unsigned allowed)
a39c14af
JK
1232{
1233 int len;
48c58471
JK
1234 struct branch *branch;
1235 struct strbuf err = STRBUF_INIT;
1236 const char *value;
a39c14af 1237
48c58471 1238 len = get_mark(name + at, namelen - at);
a39c14af
JK
1239 if (!len)
1240 return -1;
1241
3f6eb30f
JK
1242 if (memchr(name, ':', at))
1243 return -1;
1244
48c58471
JK
1245 if (at) {
1246 char *name_str = xmemdupz(name, at);
1247 branch = branch_get(name_str);
1248 free(name_str);
1249 } else
1250 branch = branch_get(NULL);
1251
1252 value = get_data(branch, &err);
1253 if (!value)
1254 die("%s", err.buf);
1255
0e9f62da
JK
1256 if (!branch_interpret_allowed(value, allowed))
1257 return -1;
1258
48c58471 1259 set_shortened_ref(buf, value);
a39c14af
JK
1260 return len + at;
1261}
1262
0e9f62da
JK
1263int interpret_branch_name(const char *name, int namelen, struct strbuf *buf,
1264 unsigned allowed)
ae0ba8e2 1265{
f278f40f 1266 char *at;
9892d5d4 1267 const char *start;
13228c30 1268 int len;
ae0ba8e2 1269
cf99a761
FC
1270 if (!namelen)
1271 namelen = strlen(name);
1272
0e9f62da
JK
1273 if (!allowed || (allowed & INTERPRET_BRANCH_LOCAL)) {
1274 len = interpret_nth_prior_checkout(name, namelen, buf);
1275 if (!len) {
1276 return len; /* syntax Ok, not enough switches */
1277 } else if (len > 0) {
1278 if (len == namelen)
1279 return len; /* consumed all */
1280 else
1281 return reinterpret(name, namelen, len, buf, allowed);
1282 }
d46a8301
JK
1283 }
1284
9892d5d4
JK
1285 for (start = name;
1286 (at = memchr(start, '@', namelen - (start - name)));
1287 start = at + 1) {
9ba89f48 1288
0e9f62da
JK
1289 if (!allowed || (allowed & INTERPRET_BRANCH_HEAD)) {
1290 len = interpret_empty_at(name, namelen, at - name, buf);
1291 if (len > 0)
1292 return reinterpret(name, namelen, len, buf,
1293 allowed);
1294 }
9ba89f48 1295
48c58471 1296 len = interpret_branch_mark(name, namelen, at - name, buf,
0e9f62da
JK
1297 upstream_mark, branch_get_upstream,
1298 allowed);
9892d5d4
JK
1299 if (len > 0)
1300 return len;
adfe5d04
JK
1301
1302 len = interpret_branch_mark(name, namelen, at - name, buf,
0e9f62da
JK
1303 push_mark, branch_get_push,
1304 allowed);
9892d5d4
JK
1305 if (len > 0)
1306 return len;
bb0dab5d 1307 }
9ba89f48 1308
a39c14af 1309 return -1;
ae0ba8e2
JH
1310}
1311
0e9f62da 1312void strbuf_branchname(struct strbuf *sb, const char *name, unsigned allowed)
6bab74e7
JN
1313{
1314 int len = strlen(name);
0e9f62da 1315 int used = interpret_branch_name(name, len, sb, allowed);
84cf2466 1316
84cf2466
JH
1317 if (used < 0)
1318 used = 0;
1319 strbuf_add(sb, name + used, len - used);
6bab74e7
JN
1320}
1321
1322int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
1323{
7d5c960b 1324 strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
6bab74e7 1325 if (name[0] == '-')
8d9c5010 1326 return -1;
6bab74e7 1327 strbuf_splice(sb, 0, 0, "refs/heads/", 11);
8d9c5010 1328 return check_refname_format(sb->buf, 0);
6bab74e7
JN
1329}
1330
9938af6a
JH
1331/*
1332 * This is like "get_sha1_basic()", except it allows "sha1 expressions",
1333 * notably "xyz^" for "parent of xyz"
1334 */
1335int get_sha1(const char *name, unsigned char *sha1)
1336{
573285e5 1337 struct object_context unused;
33bd598c 1338 return get_sha1_with_context(name, 0, sha1, &unused);
a0cd87a5
MK
1339}
1340
2764fd93 1341/*
1342 * This is like "get_sha1()", but for struct object_id.
1343 */
1344int get_oid(const char *name, struct object_id *oid)
1345{
1346 return get_sha1(name, oid->hash);
1347}
1348
1349
cd74e473 1350/*
a8a5406a 1351 * Many callers know that the user meant to name a commit-ish by
cd74e473
JH
1352 * syntactical positions where the object name appears. Calling this
1353 * function allows the machinery to disambiguate shorter-than-unique
a8a5406a 1354 * abbreviated object names between commit-ish and others.
cd74e473
JH
1355 *
1356 * Note that this does NOT error out when the named object is not a
a8a5406a 1357 * commit-ish. It is merely to give a hint to the disambiguation
cd74e473
JH
1358 * machinery.
1359 */
1360int get_sha1_committish(const char *name, unsigned char *sha1)
1361{
1362 struct object_context unused;
1363 return get_sha1_with_context(name, GET_SHA1_COMMITTISH,
1364 sha1, &unused);
1365}
1366
daba53ae
JH
1367int get_sha1_treeish(const char *name, unsigned char *sha1)
1368{
1369 struct object_context unused;
1370 return get_sha1_with_context(name, GET_SHA1_TREEISH,
1371 sha1, &unused);
1372}
1373
1374int get_sha1_commit(const char *name, unsigned char *sha1)
1375{
1376 struct object_context unused;
1377 return get_sha1_with_context(name, GET_SHA1_COMMIT,
1378 sha1, &unused);
1379}
1380
1381int get_sha1_tree(const char *name, unsigned char *sha1)
1382{
1383 struct object_context unused;
1384 return get_sha1_with_context(name, GET_SHA1_TREE,
1385 sha1, &unused);
1386}
1387
1388int get_sha1_blob(const char *name, unsigned char *sha1)
1389{
1390 struct object_context unused;
1391 return get_sha1_with_context(name, GET_SHA1_BLOB,
1392 sha1, &unused);
a0cd87a5
MK
1393}
1394
009fee47
MM
1395/* Must be called only when object_name:filename doesn't exist. */
1396static void diagnose_invalid_sha1_path(const char *prefix,
1397 const char *filename,
1398 const unsigned char *tree_sha1,
b2981d06
RS
1399 const char *object_name,
1400 int object_name_len)
009fee47 1401{
009fee47
MM
1402 unsigned char sha1[20];
1403 unsigned mode;
1404
1405 if (!prefix)
1406 prefix = "";
1407
dbe44faa 1408 if (file_exists(filename))
b2981d06
RS
1409 die("Path '%s' exists on disk, but not in '%.*s'.",
1410 filename, object_name_len, object_name);
009fee47 1411 if (errno == ENOENT || errno == ENOTDIR) {
b2724c87 1412 char *fullname = xstrfmt("%s%s", prefix, filename);
009fee47
MM
1413
1414 if (!get_tree_entry(tree_sha1, fullname,
1415 sha1, &mode)) {
1416 die("Path '%s' exists, but not '%s'.\n"
b2981d06 1417 "Did you mean '%.*s:%s' aka '%.*s:./%s'?",
009fee47
MM
1418 fullname,
1419 filename,
b2981d06 1420 object_name_len, object_name,
e41d718c 1421 fullname,
b2981d06 1422 object_name_len, object_name,
e41d718c 1423 filename);
009fee47 1424 }
b2981d06
RS
1425 die("Path '%s' does not exist in '%.*s'",
1426 filename, object_name_len, object_name);
009fee47
MM
1427 }
1428}
1429
1430/* Must be called only when :stage:filename doesn't exist. */
1431static void diagnose_invalid_index_path(int stage,
1432 const char *prefix,
1433 const char *filename)
1434{
9c5e6c80 1435 const struct cache_entry *ce;
009fee47
MM
1436 int pos;
1437 unsigned namelen = strlen(filename);
43bb66ae 1438 struct strbuf fullname = STRBUF_INIT;
009fee47
MM
1439
1440 if (!prefix)
1441 prefix = "";
1442
1443 /* Wrong stage number? */
1444 pos = cache_name_pos(filename, namelen);
1445 if (pos < 0)
1446 pos = -pos - 1;
77e8466f
MH
1447 if (pos < active_nr) {
1448 ce = active_cache[pos];
1449 if (ce_namelen(ce) == namelen &&
1450 !memcmp(ce->name, filename, namelen))
1451 die("Path '%s' is in the index, but not at stage %d.\n"
1452 "Did you mean ':%d:%s'?",
1453 filename, stage,
1454 ce_stage(ce), filename);
1455 }
009fee47
MM
1456
1457 /* Confusion between relative and absolute filenames? */
43bb66ae
JK
1458 strbuf_addstr(&fullname, prefix);
1459 strbuf_addstr(&fullname, filename);
1460 pos = cache_name_pos(fullname.buf, fullname.len);
009fee47
MM
1461 if (pos < 0)
1462 pos = -pos - 1;
77e8466f
MH
1463 if (pos < active_nr) {
1464 ce = active_cache[pos];
43bb66ae
JK
1465 if (ce_namelen(ce) == fullname.len &&
1466 !memcmp(ce->name, fullname.buf, fullname.len))
77e8466f 1467 die("Path '%s' is in the index, but not '%s'.\n"
e41d718c 1468 "Did you mean ':%d:%s' aka ':%d:./%s'?",
43bb66ae
JK
1469 fullname.buf, filename,
1470 ce_stage(ce), fullname.buf,
e41d718c 1471 ce_stage(ce), filename);
77e8466f 1472 }
009fee47 1473
dbe44faa 1474 if (file_exists(filename))
009fee47
MM
1475 die("Path '%s' exists on disk, but not in the index.", filename);
1476 if (errno == ENOENT || errno == ENOTDIR)
1477 die("Path '%s' does not exist (neither on disk nor in the index).",
1478 filename);
1479
43bb66ae 1480 strbuf_release(&fullname);
009fee47
MM
1481}
1482
1483
979f7929
NTND
1484static char *resolve_relative_path(const char *rel)
1485{
59556548 1486 if (!starts_with(rel, "./") && !starts_with(rel, "../"))
979f7929
NTND
1487 return NULL;
1488
979f7929
NTND
1489 if (!is_inside_work_tree())
1490 die("relative path syntax can't be used outside working tree.");
1491
1492 /* die() inside prefix_path() if resolved path is outside worktree */
1493 return prefix_path(startup_info->prefix,
1494 startup_info->prefix ? strlen(startup_info->prefix) : 0,
1495 rel);
1496}
1497
33bd598c
JH
1498static int get_sha1_with_context_1(const char *name,
1499 unsigned flags,
1500 const char *prefix,
1501 unsigned char *sha1,
1502 struct object_context *oc)
a0cd87a5
MK
1503{
1504 int ret, bracket_depth;
73b0e5af
JH
1505 int namelen = strlen(name);
1506 const char *cp;
33bd598c 1507 int only_to_die = flags & GET_SHA1_ONLY_TO_DIE;
5119602a 1508
7243ffdd
JK
1509 if (only_to_die)
1510 flags |= GET_SHA1_QUIETLY;
1511
573285e5
CP
1512 memset(oc, 0, sizeof(*oc));
1513 oc->mode = S_IFINVALID;
33bd598c 1514 ret = get_sha1_1(name, namelen, sha1, flags);
73b0e5af
JH
1515 if (!ret)
1516 return ret;
33bd598c
JH
1517 /*
1518 * sha1:path --> object name of path in ent sha1
979f7929
NTND
1519 * :path -> object name of absolute path in index
1520 * :./path -> object name of path relative to cwd in index
73b0e5af 1521 * :[0-3]:path -> object name of path in index at stage
95ad6d2d 1522 * :/foo -> recent commit matching foo
73b0e5af
JH
1523 */
1524 if (name[0] == ':') {
1525 int stage = 0;
9c5e6c80 1526 const struct cache_entry *ce;
979f7929 1527 char *new_path = NULL;
73b0e5af 1528 int pos;
2e83b66c 1529 if (!only_to_die && namelen > 2 && name[1] == '/') {
84baa31b 1530 struct commit_list *list = NULL;
2b2a5be3 1531
84baa31b 1532 for_each_ref(handle_one_ref, &list);
e8d1dfe6 1533 commit_list_sort_by_date(&list);
84baa31b
NTND
1534 return get_sha1_oneline(name + 2, sha1, list);
1535 }
73b0e5af
JH
1536 if (namelen < 3 ||
1537 name[2] != ':' ||
1538 name[1] < '0' || '3' < name[1])
1539 cp = name + 1;
1540 else {
1541 stage = name[1] - '0';
1542 cp = name + 3;
5119602a 1543 }
3d6e0f74
JH
1544 new_path = resolve_relative_path(cp);
1545 if (!new_path) {
1546 namelen = namelen - (cp - name);
1547 } else {
1548 cp = new_path;
1549 namelen = strlen(cp);
1550 }
573285e5 1551
2ce63e9f 1552 strlcpy(oc->path, cp, sizeof(oc->path));
573285e5 1553
73b0e5af
JH
1554 if (!active_cache)
1555 read_cache();
73b0e5af
JH
1556 pos = cache_name_pos(cp, namelen);
1557 if (pos < 0)
1558 pos = -pos - 1;
1559 while (pos < active_nr) {
1560 ce = active_cache[pos];
1561 if (ce_namelen(ce) != namelen ||
1562 memcmp(ce->name, cp, namelen))
1563 break;
1564 if (ce_stage(ce) == stage) {
99d1a986 1565 hashcpy(sha1, ce->oid.hash);
90064710 1566 oc->mode = ce->ce_mode;
979f7929 1567 free(new_path);
73b0e5af
JH
1568 return 0;
1569 }
e7cef45f 1570 pos++;
73b0e5af 1571 }
2e83b66c 1572 if (only_to_die && name[1] && name[1] != '/')
009fee47 1573 diagnose_invalid_index_path(stage, prefix, cp);
979f7929 1574 free(new_path);
73b0e5af
JH
1575 return -1;
1576 }
cce91a2c
SP
1577 for (cp = name, bracket_depth = 0; *cp; cp++) {
1578 if (*cp == '{')
1579 bracket_depth++;
1580 else if (bracket_depth && *cp == '}')
1581 bracket_depth--;
1582 else if (!bracket_depth && *cp == ':')
1583 break;
1584 }
1585 if (*cp == ':') {
73b0e5af 1586 unsigned char tree_sha1[20];
b2981d06 1587 int len = cp - name;
8a10fea4
JK
1588 unsigned sub_flags = flags;
1589
1590 sub_flags &= ~GET_SHA1_DISAMBIGUATORS;
1591 sub_flags |= GET_SHA1_TREEISH;
1592
1593 if (!get_sha1_1(name, len, tree_sha1, sub_flags)) {
009fee47 1594 const char *filename = cp+1;
979f7929
NTND
1595 char *new_filename = NULL;
1596
1597 new_filename = resolve_relative_path(filename);
1598 if (new_filename)
1599 filename = new_filename;
c4ec9677
DT
1600 if (flags & GET_SHA1_FOLLOW_SYMLINKS) {
1601 ret = get_tree_entry_follow_symlinks(tree_sha1,
1602 filename, sha1, &oc->symlink_path,
1603 &oc->mode);
1604 } else {
1605 ret = get_tree_entry(tree_sha1, filename,
1606 sha1, &oc->mode);
1607 if (ret && only_to_die) {
1608 diagnose_invalid_sha1_path(prefix,
1609 filename,
1610 tree_sha1,
1611 name, len);
1612 }
009fee47 1613 }
573285e5 1614 hashcpy(oc->tree, tree_sha1);
2ce63e9f 1615 strlcpy(oc->path, filename, sizeof(oc->path));
573285e5 1616
979f7929 1617 free(new_filename);
009fee47
MM
1618 return ret;
1619 } else {
2e83b66c 1620 if (only_to_die)
b2981d06 1621 die("Invalid object name '%.*s'.", len, name);
009fee47 1622 }
5119602a
LT
1623 }
1624 return ret;
9938af6a 1625}
f01cc14c 1626
8c135ea2
JH
1627/*
1628 * Call this function when you know "name" given by the end user must
1629 * name an object but it doesn't; the function _may_ die with a better
1630 * diagnostic message than "no such object 'name'", e.g. "Path 'doc' does not
1631 * exist in 'HEAD'" when given "HEAD:doc", or it may return in which case
1632 * you have a chance to diagnose the error further.
1633 */
1634void maybe_die_on_misspelt_object_name(const char *name, const char *prefix)
f01cc14c
JH
1635{
1636 struct object_context oc;
8c135ea2 1637 unsigned char sha1[20];
33bd598c 1638 get_sha1_with_context_1(name, GET_SHA1_ONLY_TO_DIE, prefix, sha1, &oc);
8c135ea2
JH
1639}
1640
33bd598c 1641int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc)
f01cc14c 1642{
c4ec9677
DT
1643 if (flags & GET_SHA1_FOLLOW_SYMLINKS && flags & GET_SHA1_ONLY_TO_DIE)
1644 die("BUG: incompatible flags for get_sha1_with_context");
33bd598c 1645 return get_sha1_with_context_1(str, flags, NULL, sha1, orc);
f01cc14c 1646}