Merge branch 'kk/revwalk-slop-too-many-commit-within-a-second' into maint-1.8.1
[git/jnareb-git.git] / sha1_name.c
blobc50630a3ea793e0cfd2510b8813129a1685428f4
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"
10 static int get_sha1_oneline(const char *, unsigned char *, struct commit_list *);
12 typedef int (*disambiguate_hint_fn)(const unsigned char *, void *);
14 struct disambiguate_state {
15 disambiguate_hint_fn fn;
16 void *cb_data;
17 unsigned char candidate[20];
18 unsigned candidate_exists:1;
19 unsigned candidate_checked:1;
20 unsigned candidate_ok:1;
21 unsigned disambiguate_fn_used:1;
22 unsigned ambiguous:1;
23 unsigned always_call_fn:1;
26 static void update_candidates(struct disambiguate_state *ds, const unsigned char *current)
28 if (ds->always_call_fn) {
29 ds->ambiguous = ds->fn(current, ds->cb_data) ? 1 : 0;
30 return;
32 if (!ds->candidate_exists) {
33 /* this is the first candidate */
34 hashcpy(ds->candidate, current);
35 ds->candidate_exists = 1;
36 return;
37 } else if (!hashcmp(ds->candidate, current)) {
38 /* the same as what we already have seen */
39 return;
42 if (!ds->fn) {
43 /* cannot disambiguate between ds->candidate and current */
44 ds->ambiguous = 1;
45 return;
48 if (!ds->candidate_checked) {
49 ds->candidate_ok = ds->fn(ds->candidate, ds->cb_data);
50 ds->disambiguate_fn_used = 1;
51 ds->candidate_checked = 1;
54 if (!ds->candidate_ok) {
55 /* discard the candidate; we know it does not satisify fn */
56 hashcpy(ds->candidate, current);
57 ds->candidate_checked = 0;
58 return;
61 /* if we reach this point, we know ds->candidate satisfies fn */
62 if (ds->fn(current, ds->cb_data)) {
64 * if both current and candidate satisfy fn, we cannot
65 * disambiguate.
67 ds->candidate_ok = 0;
68 ds->ambiguous = 1;
71 /* otherwise, current can be discarded and candidate is still good */
74 static void find_short_object_filename(int len, const char *hex_pfx, struct disambiguate_state *ds)
76 struct alternate_object_database *alt;
77 char hex[40];
78 static struct alternate_object_database *fakeent;
80 if (!fakeent) {
82 * Create a "fake" alternate object database that
83 * points to our own object database, to make it
84 * easier to get a temporary working space in
85 * alt->name/alt->base while iterating over the
86 * object databases including our own.
88 const char *objdir = get_object_directory();
89 int objdir_len = strlen(objdir);
90 int entlen = objdir_len + 43;
91 fakeent = xmalloc(sizeof(*fakeent) + entlen);
92 memcpy(fakeent->base, objdir, objdir_len);
93 fakeent->name = fakeent->base + objdir_len + 1;
94 fakeent->name[-1] = '/';
96 fakeent->next = alt_odb_list;
98 sprintf(hex, "%.2s", hex_pfx);
99 for (alt = fakeent; alt && !ds->ambiguous; alt = alt->next) {
100 struct dirent *de;
101 DIR *dir;
102 sprintf(alt->name, "%.2s/", hex_pfx);
103 dir = opendir(alt->base);
104 if (!dir)
105 continue;
107 while (!ds->ambiguous && (de = readdir(dir)) != NULL) {
108 unsigned char sha1[20];
110 if (strlen(de->d_name) != 38)
111 continue;
112 if (memcmp(de->d_name, hex_pfx + 2, len - 2))
113 continue;
114 memcpy(hex + 2, de->d_name, 38);
115 if (!get_sha1_hex(hex, sha1))
116 update_candidates(ds, sha1);
118 closedir(dir);
122 static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
124 do {
125 if (*a != *b)
126 return 0;
127 a++;
128 b++;
129 len -= 2;
130 } while (len > 1);
131 if (len)
132 if ((*a ^ *b) & 0xf0)
133 return 0;
134 return 1;
137 static void unique_in_pack(int len,
138 const unsigned char *bin_pfx,
139 struct packed_git *p,
140 struct disambiguate_state *ds)
142 uint32_t num, last, i, first = 0;
143 const unsigned char *current = NULL;
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;
153 current = nth_packed_object_sha1(p, mid);
154 cmp = hashcmp(bin_pfx, current);
155 if (!cmp) {
156 first = mid;
157 break;
159 if (cmp > 0) {
160 first = mid+1;
161 continue;
163 last = mid;
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).
171 for (i = first; i < num && !ds->ambiguous; i++) {
172 current = nth_packed_object_sha1(p, i);
173 if (!match_sha(len, bin_pfx, current))
174 break;
175 update_candidates(ds, current);
179 static void find_short_packed_object(int len, const unsigned char *bin_pfx,
180 struct disambiguate_state *ds)
182 struct packed_git *p;
184 prepare_packed_git();
185 for (p = packed_git; p && !ds->ambiguous; p = p->next)
186 unique_in_pack(len, bin_pfx, p, ds);
189 #define SHORT_NAME_NOT_FOUND (-1)
190 #define SHORT_NAME_AMBIGUOUS (-2)
192 static int finish_object_disambiguation(struct disambiguate_state *ds,
193 unsigned char *sha1)
195 if (ds->ambiguous)
196 return SHORT_NAME_AMBIGUOUS;
198 if (!ds->candidate_exists)
199 return SHORT_NAME_NOT_FOUND;
201 if (!ds->candidate_checked)
203 * If this is the only candidate, there is no point
204 * calling the disambiguation hint callback.
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!
216 ds->candidate_ok = (!ds->disambiguate_fn_used ||
217 ds->fn(ds->candidate, ds->cb_data));
219 if (!ds->candidate_ok)
220 return SHORT_NAME_AMBIGUOUS;
222 hashcpy(sha1, ds->candidate);
223 return 0;
226 static int disambiguate_commit_only(const unsigned char *sha1, void *cb_data_unused)
228 int kind = sha1_object_info(sha1, NULL);
229 return kind == OBJ_COMMIT;
232 static int disambiguate_committish_only(const unsigned char *sha1, void *cb_data_unused)
234 struct object *obj;
235 int kind;
237 kind = sha1_object_info(sha1, NULL);
238 if (kind == OBJ_COMMIT)
239 return 1;
240 if (kind != OBJ_TAG)
241 return 0;
243 /* We need to do this the hard way... */
244 obj = deref_tag(lookup_object(sha1), NULL, 0);
245 if (obj && obj->type == OBJ_COMMIT)
246 return 1;
247 return 0;
250 static int disambiguate_tree_only(const unsigned char *sha1, void *cb_data_unused)
252 int kind = sha1_object_info(sha1, NULL);
253 return kind == OBJ_TREE;
256 static int disambiguate_treeish_only(const unsigned char *sha1, void *cb_data_unused)
258 struct object *obj;
259 int kind;
261 kind = sha1_object_info(sha1, NULL);
262 if (kind == OBJ_TREE || kind == OBJ_COMMIT)
263 return 1;
264 if (kind != OBJ_TAG)
265 return 0;
267 /* We need to do this the hard way... */
268 obj = deref_tag(lookup_object(sha1), NULL, 0);
269 if (obj && (obj->type == OBJ_TREE || obj->type == OBJ_COMMIT))
270 return 1;
271 return 0;
274 static int disambiguate_blob_only(const unsigned char *sha1, void *cb_data_unused)
276 int kind = sha1_object_info(sha1, NULL);
277 return kind == OBJ_BLOB;
280 static int prepare_prefixes(const char *name, int len,
281 unsigned char *bin_pfx,
282 char *hex_pfx)
284 int i;
286 hashclr(bin_pfx);
287 memset(hex_pfx, 'x', 40);
288 for (i = 0; i < len ;i++) {
289 unsigned char c = name[i];
290 unsigned char val;
291 if (c >= '0' && c <= '9')
292 val = c - '0';
293 else if (c >= 'a' && c <= 'f')
294 val = c - 'a' + 10;
295 else if (c >= 'A' && c <='F') {
296 val = c - 'A' + 10;
297 c -= 'A' - 'a';
299 else
300 return -1;
301 hex_pfx[i] = c;
302 if (!(i & 1))
303 val <<= 4;
304 bin_pfx[i >> 1] |= val;
306 return 0;
309 static int get_short_sha1(const char *name, int len, unsigned char *sha1,
310 unsigned flags)
312 int status;
313 char hex_pfx[40];
314 unsigned char bin_pfx[20];
315 struct disambiguate_state ds;
316 int quietly = !!(flags & GET_SHA1_QUIETLY);
318 if (len < MINIMUM_ABBREV || len > 40)
319 return -1;
320 if (prepare_prefixes(name, len, bin_pfx, hex_pfx) < 0)
321 return -1;
323 prepare_alt_odb();
325 memset(&ds, 0, sizeof(ds));
326 if (flags & GET_SHA1_COMMIT)
327 ds.fn = disambiguate_commit_only;
328 else if (flags & GET_SHA1_COMMITTISH)
329 ds.fn = disambiguate_committish_only;
330 else if (flags & GET_SHA1_TREE)
331 ds.fn = disambiguate_tree_only;
332 else if (flags & GET_SHA1_TREEISH)
333 ds.fn = disambiguate_treeish_only;
334 else if (flags & GET_SHA1_BLOB)
335 ds.fn = disambiguate_blob_only;
337 find_short_object_filename(len, hex_pfx, &ds);
338 find_short_packed_object(len, bin_pfx, &ds);
339 status = finish_object_disambiguation(&ds, sha1);
341 if (!quietly && (status == SHORT_NAME_AMBIGUOUS))
342 return error("short SHA1 %.*s is ambiguous.", len, hex_pfx);
343 return status;
347 int for_each_abbrev(const char *prefix, each_abbrev_fn fn, void *cb_data)
349 char hex_pfx[40];
350 unsigned char bin_pfx[20];
351 struct disambiguate_state ds;
352 int len = strlen(prefix);
354 if (len < MINIMUM_ABBREV || len > 40)
355 return -1;
356 if (prepare_prefixes(prefix, len, bin_pfx, hex_pfx) < 0)
357 return -1;
359 prepare_alt_odb();
361 memset(&ds, 0, sizeof(ds));
362 ds.always_call_fn = 1;
363 ds.cb_data = cb_data;
364 ds.fn = fn;
366 find_short_object_filename(len, hex_pfx, &ds);
367 find_short_packed_object(len, bin_pfx, &ds);
368 return ds.ambiguous;
371 const char *find_unique_abbrev(const unsigned char *sha1, int len)
373 int status, exists;
374 static char hex[41];
376 exists = has_sha1_file(sha1);
377 memcpy(hex, sha1_to_hex(sha1), 40);
378 if (len == 40 || !len)
379 return hex;
380 while (len < 40) {
381 unsigned char sha1_ret[20];
382 status = get_short_sha1(hex, len, sha1_ret, GET_SHA1_QUIETLY);
383 if (exists
384 ? !status
385 : status == SHORT_NAME_NOT_FOUND) {
386 hex[len] = 0;
387 return hex;
389 len++;
391 return hex;
394 static int ambiguous_path(const char *path, int len)
396 int slash = 1;
397 int cnt;
399 for (cnt = 0; cnt < len; cnt++) {
400 switch (*path++) {
401 case '\0':
402 break;
403 case '/':
404 if (slash)
405 break;
406 slash = 1;
407 continue;
408 case '.':
409 continue;
410 default:
411 slash = 0;
412 continue;
414 break;
416 return slash;
419 static inline int upstream_mark(const char *string, int len)
421 const char *suffix[] = { "@{upstream}", "@{u}" };
422 int i;
424 for (i = 0; i < ARRAY_SIZE(suffix); i++) {
425 int suffix_len = strlen(suffix[i]);
426 if (suffix_len <= len
427 && !memcmp(string, suffix[i], suffix_len))
428 return suffix_len;
430 return 0;
433 static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags);
435 static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
437 static const char *warn_msg = "refname '%.*s' is ambiguous.";
438 char *real_ref = NULL;
439 int refs_found = 0;
440 int at, reflog_len;
442 if (len == 40 && !get_sha1_hex(str, sha1))
443 return 0;
445 /* basic@{time or number or -number} format to query ref-log */
446 reflog_len = at = 0;
447 if (len && str[len-1] == '}') {
448 for (at = len-2; at >= 0; at--) {
449 if (str[at] == '@' && str[at+1] == '{') {
450 if (!upstream_mark(str + at, len - at)) {
451 reflog_len = (len-1) - (at+2);
452 len = at;
454 break;
459 /* Accept only unambiguous ref paths. */
460 if (len && ambiguous_path(str, len))
461 return -1;
463 if (!len && reflog_len) {
464 struct strbuf buf = STRBUF_INIT;
465 int ret;
466 /* try the @{-N} syntax for n-th checkout */
467 ret = interpret_branch_name(str+at, &buf);
468 if (ret > 0) {
469 /* substitute this branch name and restart */
470 return get_sha1_1(buf.buf, buf.len, sha1, 0);
471 } else if (ret == 0) {
472 return -1;
474 /* allow "@{...}" to mean the current branch reflog */
475 refs_found = dwim_ref("HEAD", 4, sha1, &real_ref);
476 } else if (reflog_len)
477 refs_found = dwim_log(str, len, sha1, &real_ref);
478 else
479 refs_found = dwim_ref(str, len, sha1, &real_ref);
481 if (!refs_found)
482 return -1;
484 if (warn_ambiguous_refs && refs_found > 1)
485 warning(warn_msg, len, str);
487 if (reflog_len) {
488 int nth, i;
489 unsigned long at_time;
490 unsigned long co_time;
491 int co_tz, co_cnt;
493 /* a @{-N} placed anywhere except the start is an error */
494 if (str[at+2] == '-')
495 return -1;
497 /* Is it asking for N-th entry, or approxidate? */
498 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
499 char ch = str[at+2+i];
500 if ('0' <= ch && ch <= '9')
501 nth = nth * 10 + ch - '0';
502 else
503 nth = -1;
505 if (100000000 <= nth) {
506 at_time = nth;
507 nth = -1;
508 } else if (0 <= nth)
509 at_time = 0;
510 else {
511 int errors = 0;
512 char *tmp = xstrndup(str + at + 2, reflog_len);
513 at_time = approxidate_careful(tmp, &errors);
514 free(tmp);
515 if (errors)
516 return -1;
518 if (read_ref_at(real_ref, at_time, nth, sha1, NULL,
519 &co_time, &co_tz, &co_cnt)) {
520 if (at_time)
521 warning("Log for '%.*s' only goes "
522 "back to %s.", len, str,
523 show_date(co_time, co_tz, DATE_RFC2822));
524 else {
525 free(real_ref);
526 die("Log for '%.*s' only has %d entries.",
527 len, str, co_cnt);
532 free(real_ref);
533 return 0;
536 static int get_parent(const char *name, int len,
537 unsigned char *result, int idx)
539 unsigned char sha1[20];
540 int ret = get_sha1_1(name, len, sha1, GET_SHA1_COMMITTISH);
541 struct commit *commit;
542 struct commit_list *p;
544 if (ret)
545 return ret;
546 commit = lookup_commit_reference(sha1);
547 if (!commit)
548 return -1;
549 if (parse_commit(commit))
550 return -1;
551 if (!idx) {
552 hashcpy(result, commit->object.sha1);
553 return 0;
555 p = commit->parents;
556 while (p) {
557 if (!--idx) {
558 hashcpy(result, p->item->object.sha1);
559 return 0;
561 p = p->next;
563 return -1;
566 static int get_nth_ancestor(const char *name, int len,
567 unsigned char *result, int generation)
569 unsigned char sha1[20];
570 struct commit *commit;
571 int ret;
573 ret = get_sha1_1(name, len, sha1, GET_SHA1_COMMITTISH);
574 if (ret)
575 return ret;
576 commit = lookup_commit_reference(sha1);
577 if (!commit)
578 return -1;
580 while (generation--) {
581 if (parse_commit(commit) || !commit->parents)
582 return -1;
583 commit = commit->parents->item;
585 hashcpy(result, commit->object.sha1);
586 return 0;
589 struct object *peel_to_type(const char *name, int namelen,
590 struct object *o, enum object_type expected_type)
592 if (name && !namelen)
593 namelen = strlen(name);
594 while (1) {
595 if (!o || (!o->parsed && !parse_object(o->sha1)))
596 return NULL;
597 if (o->type == expected_type)
598 return o;
599 if (o->type == OBJ_TAG)
600 o = ((struct tag*) o)->tagged;
601 else if (o->type == OBJ_COMMIT)
602 o = &(((struct commit *) o)->tree->object);
603 else {
604 if (name)
605 error("%.*s: expected %s type, but the object "
606 "dereferences to %s type",
607 namelen, name, typename(expected_type),
608 typename(o->type));
609 return NULL;
614 static int peel_onion(const char *name, int len, unsigned char *sha1)
616 unsigned char outer[20];
617 const char *sp;
618 unsigned int expected_type = 0;
619 unsigned lookup_flags = 0;
620 struct object *o;
623 * "ref^{type}" dereferences ref repeatedly until you cannot
624 * dereference anymore, or you get an object of given type,
625 * whichever comes first. "ref^{}" means just dereference
626 * tags until you get a non-tag. "ref^0" is a shorthand for
627 * "ref^{commit}". "commit^{tree}" could be used to find the
628 * top-level tree of the given commit.
630 if (len < 4 || name[len-1] != '}')
631 return -1;
633 for (sp = name + len - 1; name <= sp; sp--) {
634 int ch = *sp;
635 if (ch == '{' && name < sp && sp[-1] == '^')
636 break;
638 if (sp <= name)
639 return -1;
641 sp++; /* beginning of type name, or closing brace for empty */
642 if (!strncmp(commit_type, sp, 6) && sp[6] == '}')
643 expected_type = OBJ_COMMIT;
644 else if (!strncmp(tree_type, sp, 4) && sp[4] == '}')
645 expected_type = OBJ_TREE;
646 else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
647 expected_type = OBJ_BLOB;
648 else if (sp[0] == '}')
649 expected_type = OBJ_NONE;
650 else if (sp[0] == '/')
651 expected_type = OBJ_COMMIT;
652 else
653 return -1;
655 if (expected_type == OBJ_COMMIT)
656 lookup_flags = GET_SHA1_COMMITTISH;
658 if (get_sha1_1(name, sp - name - 2, outer, lookup_flags))
659 return -1;
661 o = parse_object(outer);
662 if (!o)
663 return -1;
664 if (!expected_type) {
665 o = deref_tag(o, name, sp - name - 2);
666 if (!o || (!o->parsed && !parse_object(o->sha1)))
667 return -1;
668 hashcpy(sha1, o->sha1);
669 return 0;
673 * At this point, the syntax look correct, so
674 * if we do not get the needed object, we should
675 * barf.
677 o = peel_to_type(name, len, o, expected_type);
678 if (!o)
679 return -1;
681 hashcpy(sha1, o->sha1);
682 if (sp[0] == '/') {
683 /* "$commit^{/foo}" */
684 char *prefix;
685 int ret;
686 struct commit_list *list = NULL;
689 * $commit^{/}. Some regex implementation may reject.
690 * We don't need regex anyway. '' pattern always matches.
692 if (sp[1] == '}')
693 return 0;
695 prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
696 commit_list_insert((struct commit *)o, &list);
697 ret = get_sha1_oneline(prefix, sha1, list);
698 free(prefix);
699 return ret;
701 return 0;
704 static int get_describe_name(const char *name, int len, unsigned char *sha1)
706 const char *cp;
707 unsigned flags = GET_SHA1_QUIETLY | GET_SHA1_COMMIT;
709 for (cp = name + len - 1; name + 2 <= cp; cp--) {
710 char ch = *cp;
711 if (hexval(ch) & ~0377) {
712 /* We must be looking at g in "SOMETHING-g"
713 * for it to be describe output.
715 if (ch == 'g' && cp[-1] == '-') {
716 cp++;
717 len -= cp - name;
718 return get_short_sha1(cp, len, sha1, flags);
722 return -1;
725 static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags)
727 int ret, has_suffix;
728 const char *cp;
731 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
733 has_suffix = 0;
734 for (cp = name + len - 1; name <= cp; cp--) {
735 int ch = *cp;
736 if ('0' <= ch && ch <= '9')
737 continue;
738 if (ch == '~' || ch == '^')
739 has_suffix = ch;
740 break;
743 if (has_suffix) {
744 int num = 0;
745 int len1 = cp - name;
746 cp++;
747 while (cp < name + len)
748 num = num * 10 + *cp++ - '0';
749 if (!num && len1 == len - 1)
750 num = 1;
751 if (has_suffix == '^')
752 return get_parent(name, len1, sha1, num);
753 /* else if (has_suffix == '~') -- goes without saying */
754 return get_nth_ancestor(name, len1, sha1, num);
757 ret = peel_onion(name, len, sha1);
758 if (!ret)
759 return 0;
761 ret = get_sha1_basic(name, len, sha1);
762 if (!ret)
763 return 0;
765 /* It could be describe output that is "SOMETHING-gXXXX" */
766 ret = get_describe_name(name, len, sha1);
767 if (!ret)
768 return 0;
770 return get_short_sha1(name, len, sha1, lookup_flags);
774 * This interprets names like ':/Initial revision of "git"' by searching
775 * through history and returning the first commit whose message starts
776 * the given regular expression.
778 * For future extension, ':/!' is reserved. If you want to match a message
779 * beginning with a '!', you have to repeat the exclamation mark.
781 #define ONELINE_SEEN (1u<<20)
783 static int handle_one_ref(const char *path,
784 const unsigned char *sha1, int flag, void *cb_data)
786 struct commit_list **list = cb_data;
787 struct object *object = parse_object(sha1);
788 if (!object)
789 return 0;
790 if (object->type == OBJ_TAG) {
791 object = deref_tag(object, path, strlen(path));
792 if (!object)
793 return 0;
795 if (object->type != OBJ_COMMIT)
796 return 0;
797 commit_list_insert_by_date((struct commit *)object, list);
798 return 0;
801 static int get_sha1_oneline(const char *prefix, unsigned char *sha1,
802 struct commit_list *list)
804 struct commit_list *backup = NULL, *l;
805 int found = 0;
806 regex_t regex;
808 if (prefix[0] == '!') {
809 if (prefix[1] != '!')
810 die ("Invalid search pattern: %s", prefix);
811 prefix++;
814 if (regcomp(&regex, prefix, REG_EXTENDED))
815 die("Invalid search pattern: %s", prefix);
817 for (l = list; l; l = l->next) {
818 l->item->object.flags |= ONELINE_SEEN;
819 commit_list_insert(l->item, &backup);
821 while (list) {
822 char *p, *to_free = NULL;
823 struct commit *commit;
824 enum object_type type;
825 unsigned long size;
826 int matches;
828 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
829 if (!parse_object(commit->object.sha1))
830 continue;
831 if (commit->buffer)
832 p = commit->buffer;
833 else {
834 p = read_sha1_file(commit->object.sha1, &type, &size);
835 if (!p)
836 continue;
837 to_free = p;
840 p = strstr(p, "\n\n");
841 matches = p && !regexec(&regex, p + 2, 0, NULL, 0);
842 free(to_free);
844 if (matches) {
845 hashcpy(sha1, commit->object.sha1);
846 found = 1;
847 break;
850 regfree(&regex);
851 free_commit_list(list);
852 for (l = backup; l; l = l->next)
853 clear_commit_marks(l->item, ONELINE_SEEN);
854 free_commit_list(backup);
855 return found ? 0 : -1;
858 struct grab_nth_branch_switch_cbdata {
859 long cnt, alloc;
860 struct strbuf *buf;
863 static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
864 const char *email, unsigned long timestamp, int tz,
865 const char *message, void *cb_data)
867 struct grab_nth_branch_switch_cbdata *cb = cb_data;
868 const char *match = NULL, *target = NULL;
869 size_t len;
870 int nth;
872 if (!prefixcmp(message, "checkout: moving from ")) {
873 match = message + strlen("checkout: moving from ");
874 target = strstr(match, " to ");
877 if (!match || !target)
878 return 0;
880 len = target - match;
881 nth = cb->cnt++ % cb->alloc;
882 strbuf_reset(&cb->buf[nth]);
883 strbuf_add(&cb->buf[nth], match, len);
884 return 0;
888 * Parse @{-N} syntax, return the number of characters parsed
889 * if successful; otherwise signal an error with negative value.
891 static int interpret_nth_prior_checkout(const char *name, struct strbuf *buf)
893 long nth;
894 int i, retval;
895 struct grab_nth_branch_switch_cbdata cb;
896 const char *brace;
897 char *num_end;
899 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
900 return -1;
901 brace = strchr(name, '}');
902 if (!brace)
903 return -1;
904 nth = strtol(name+3, &num_end, 10);
905 if (num_end != brace)
906 return -1;
907 if (nth <= 0)
908 return -1;
909 cb.alloc = nth;
910 cb.buf = xmalloc(nth * sizeof(struct strbuf));
911 for (i = 0; i < nth; i++)
912 strbuf_init(&cb.buf[i], 20);
913 cb.cnt = 0;
914 retval = 0;
915 for_each_recent_reflog_ent("HEAD", grab_nth_branch_switch, 40960, &cb);
916 if (cb.cnt < nth) {
917 cb.cnt = 0;
918 for_each_reflog_ent("HEAD", grab_nth_branch_switch, &cb);
920 if (cb.cnt < nth)
921 goto release_return;
922 i = cb.cnt % nth;
923 strbuf_reset(buf);
924 strbuf_add(buf, cb.buf[i].buf, cb.buf[i].len);
925 retval = brace-name+1;
927 release_return:
928 for (i = 0; i < nth; i++)
929 strbuf_release(&cb.buf[i]);
930 free(cb.buf);
932 return retval;
935 int get_sha1_mb(const char *name, unsigned char *sha1)
937 struct commit *one, *two;
938 struct commit_list *mbs;
939 unsigned char sha1_tmp[20];
940 const char *dots;
941 int st;
943 dots = strstr(name, "...");
944 if (!dots)
945 return get_sha1(name, sha1);
946 if (dots == name)
947 st = get_sha1("HEAD", sha1_tmp);
948 else {
949 struct strbuf sb;
950 strbuf_init(&sb, dots - name);
951 strbuf_add(&sb, name, dots - name);
952 st = get_sha1_committish(sb.buf, sha1_tmp);
953 strbuf_release(&sb);
955 if (st)
956 return st;
957 one = lookup_commit_reference_gently(sha1_tmp, 0);
958 if (!one)
959 return -1;
961 if (get_sha1_committish(dots[3] ? (dots + 3) : "HEAD", sha1_tmp))
962 return -1;
963 two = lookup_commit_reference_gently(sha1_tmp, 0);
964 if (!two)
965 return -1;
966 mbs = get_merge_bases(one, two, 1);
967 if (!mbs || mbs->next)
968 st = -1;
969 else {
970 st = 0;
971 hashcpy(sha1, mbs->item->object.sha1);
973 free_commit_list(mbs);
974 return st;
978 * This reads short-hand syntax that not only evaluates to a commit
979 * object name, but also can act as if the end user spelled the name
980 * of the branch from the command line.
982 * - "@{-N}" finds the name of the Nth previous branch we were on, and
983 * places the name of the branch in the given buf and returns the
984 * number of characters parsed if successful.
986 * - "<branch>@{upstream}" finds the name of the other ref that
987 * <branch> is configured to merge with (missing <branch> defaults
988 * to the current branch), and places the name of the branch in the
989 * given buf and returns the number of characters parsed if
990 * successful.
992 * If the input is not of the accepted format, it returns a negative
993 * number to signal an error.
995 * If the input was ok but there are not N branch switches in the
996 * reflog, it returns 0.
998 int interpret_branch_name(const char *name, struct strbuf *buf)
1000 char *cp;
1001 struct branch *upstream;
1002 int namelen = strlen(name);
1003 int len = interpret_nth_prior_checkout(name, buf);
1004 int tmp_len;
1006 if (!len)
1007 return len; /* syntax Ok, not enough switches */
1008 if (0 < len && len == namelen)
1009 return len; /* consumed all */
1010 else if (0 < len) {
1011 /* we have extra data, which might need further processing */
1012 struct strbuf tmp = STRBUF_INIT;
1013 int used = buf->len;
1014 int ret;
1016 strbuf_add(buf, name + len, namelen - len);
1017 ret = interpret_branch_name(buf->buf, &tmp);
1018 /* that data was not interpreted, remove our cruft */
1019 if (ret < 0) {
1020 strbuf_setlen(buf, used);
1021 return len;
1023 strbuf_reset(buf);
1024 strbuf_addbuf(buf, &tmp);
1025 strbuf_release(&tmp);
1026 /* tweak for size of {-N} versus expanded ref name */
1027 return ret - used + len;
1030 cp = strchr(name, '@');
1031 if (!cp)
1032 return -1;
1033 tmp_len = upstream_mark(cp, namelen - (cp - name));
1034 if (!tmp_len)
1035 return -1;
1036 len = cp + tmp_len - name;
1037 cp = xstrndup(name, cp - name);
1038 upstream = branch_get(*cp ? cp : NULL);
1040 * Upstream can be NULL only if cp refers to HEAD and HEAD
1041 * points to something different than a branch.
1043 if (!upstream)
1044 return error(_("HEAD does not point to a branch"));
1045 if (!upstream->merge || !upstream->merge[0]->dst) {
1046 if (!ref_exists(upstream->refname))
1047 return error(_("No such branch: '%s'"), cp);
1048 if (!upstream->merge)
1049 return error(_("No upstream configured for branch '%s'"),
1050 upstream->name);
1051 return error(
1052 _("Upstream branch '%s' not stored as a remote-tracking branch"),
1053 upstream->merge[0]->src);
1055 free(cp);
1056 cp = shorten_unambiguous_ref(upstream->merge[0]->dst, 0);
1057 strbuf_reset(buf);
1058 strbuf_addstr(buf, cp);
1059 free(cp);
1060 return len;
1063 int strbuf_branchname(struct strbuf *sb, const char *name)
1065 int len = strlen(name);
1066 if (interpret_branch_name(name, sb) == len)
1067 return 0;
1068 strbuf_add(sb, name, len);
1069 return len;
1072 int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
1074 strbuf_branchname(sb, name);
1075 if (name[0] == '-')
1076 return -1;
1077 strbuf_splice(sb, 0, 0, "refs/heads/", 11);
1078 return check_refname_format(sb->buf, 0);
1082 * This is like "get_sha1_basic()", except it allows "sha1 expressions",
1083 * notably "xyz^" for "parent of xyz"
1085 int get_sha1(const char *name, unsigned char *sha1)
1087 struct object_context unused;
1088 return get_sha1_with_context(name, 0, sha1, &unused);
1092 * Many callers know that the user meant to name a committish by
1093 * syntactical positions where the object name appears. Calling this
1094 * function allows the machinery to disambiguate shorter-than-unique
1095 * abbreviated object names between committish and others.
1097 * Note that this does NOT error out when the named object is not a
1098 * committish. It is merely to give a hint to the disambiguation
1099 * machinery.
1101 int get_sha1_committish(const char *name, unsigned char *sha1)
1103 struct object_context unused;
1104 return get_sha1_with_context(name, GET_SHA1_COMMITTISH,
1105 sha1, &unused);
1108 int get_sha1_treeish(const char *name, unsigned char *sha1)
1110 struct object_context unused;
1111 return get_sha1_with_context(name, GET_SHA1_TREEISH,
1112 sha1, &unused);
1115 int get_sha1_commit(const char *name, unsigned char *sha1)
1117 struct object_context unused;
1118 return get_sha1_with_context(name, GET_SHA1_COMMIT,
1119 sha1, &unused);
1122 int get_sha1_tree(const char *name, unsigned char *sha1)
1124 struct object_context unused;
1125 return get_sha1_with_context(name, GET_SHA1_TREE,
1126 sha1, &unused);
1129 int get_sha1_blob(const char *name, unsigned char *sha1)
1131 struct object_context unused;
1132 return get_sha1_with_context(name, GET_SHA1_BLOB,
1133 sha1, &unused);
1136 /* Must be called only when object_name:filename doesn't exist. */
1137 static void diagnose_invalid_sha1_path(const char *prefix,
1138 const char *filename,
1139 const unsigned char *tree_sha1,
1140 const char *object_name,
1141 int object_name_len)
1143 struct stat st;
1144 unsigned char sha1[20];
1145 unsigned mode;
1147 if (!prefix)
1148 prefix = "";
1150 if (!lstat(filename, &st))
1151 die("Path '%s' exists on disk, but not in '%.*s'.",
1152 filename, object_name_len, object_name);
1153 if (errno == ENOENT || errno == ENOTDIR) {
1154 char *fullname = xmalloc(strlen(filename)
1155 + strlen(prefix) + 1);
1156 strcpy(fullname, prefix);
1157 strcat(fullname, filename);
1159 if (!get_tree_entry(tree_sha1, fullname,
1160 sha1, &mode)) {
1161 die("Path '%s' exists, but not '%s'.\n"
1162 "Did you mean '%.*s:%s' aka '%.*s:./%s'?",
1163 fullname,
1164 filename,
1165 object_name_len, object_name,
1166 fullname,
1167 object_name_len, object_name,
1168 filename);
1170 die("Path '%s' does not exist in '%.*s'",
1171 filename, object_name_len, object_name);
1175 /* Must be called only when :stage:filename doesn't exist. */
1176 static void diagnose_invalid_index_path(int stage,
1177 const char *prefix,
1178 const char *filename)
1180 struct stat st;
1181 struct cache_entry *ce;
1182 int pos;
1183 unsigned namelen = strlen(filename);
1184 unsigned fullnamelen;
1185 char *fullname;
1187 if (!prefix)
1188 prefix = "";
1190 /* Wrong stage number? */
1191 pos = cache_name_pos(filename, namelen);
1192 if (pos < 0)
1193 pos = -pos - 1;
1194 if (pos < active_nr) {
1195 ce = active_cache[pos];
1196 if (ce_namelen(ce) == namelen &&
1197 !memcmp(ce->name, filename, namelen))
1198 die("Path '%s' is in the index, but not at stage %d.\n"
1199 "Did you mean ':%d:%s'?",
1200 filename, stage,
1201 ce_stage(ce), filename);
1204 /* Confusion between relative and absolute filenames? */
1205 fullnamelen = namelen + strlen(prefix);
1206 fullname = xmalloc(fullnamelen + 1);
1207 strcpy(fullname, prefix);
1208 strcat(fullname, filename);
1209 pos = cache_name_pos(fullname, fullnamelen);
1210 if (pos < 0)
1211 pos = -pos - 1;
1212 if (pos < active_nr) {
1213 ce = active_cache[pos];
1214 if (ce_namelen(ce) == fullnamelen &&
1215 !memcmp(ce->name, fullname, fullnamelen))
1216 die("Path '%s' is in the index, but not '%s'.\n"
1217 "Did you mean ':%d:%s' aka ':%d:./%s'?",
1218 fullname, filename,
1219 ce_stage(ce), fullname,
1220 ce_stage(ce), filename);
1223 if (!lstat(filename, &st))
1224 die("Path '%s' exists on disk, but not in the index.", filename);
1225 if (errno == ENOENT || errno == ENOTDIR)
1226 die("Path '%s' does not exist (neither on disk nor in the index).",
1227 filename);
1229 free(fullname);
1233 static char *resolve_relative_path(const char *rel)
1235 if (prefixcmp(rel, "./") && prefixcmp(rel, "../"))
1236 return NULL;
1238 if (!startup_info)
1239 die("BUG: startup_info struct is not initialized.");
1241 if (!is_inside_work_tree())
1242 die("relative path syntax can't be used outside working tree.");
1244 /* die() inside prefix_path() if resolved path is outside worktree */
1245 return prefix_path(startup_info->prefix,
1246 startup_info->prefix ? strlen(startup_info->prefix) : 0,
1247 rel);
1250 static int get_sha1_with_context_1(const char *name,
1251 unsigned flags,
1252 const char *prefix,
1253 unsigned char *sha1,
1254 struct object_context *oc)
1256 int ret, bracket_depth;
1257 int namelen = strlen(name);
1258 const char *cp;
1259 int only_to_die = flags & GET_SHA1_ONLY_TO_DIE;
1261 memset(oc, 0, sizeof(*oc));
1262 oc->mode = S_IFINVALID;
1263 ret = get_sha1_1(name, namelen, sha1, flags);
1264 if (!ret)
1265 return ret;
1267 * sha1:path --> object name of path in ent sha1
1268 * :path -> object name of absolute path in index
1269 * :./path -> object name of path relative to cwd in index
1270 * :[0-3]:path -> object name of path in index at stage
1271 * :/foo -> recent commit matching foo
1273 if (name[0] == ':') {
1274 int stage = 0;
1275 struct cache_entry *ce;
1276 char *new_path = NULL;
1277 int pos;
1278 if (!only_to_die && namelen > 2 && name[1] == '/') {
1279 struct commit_list *list = NULL;
1280 for_each_ref(handle_one_ref, &list);
1281 return get_sha1_oneline(name + 2, sha1, list);
1283 if (namelen < 3 ||
1284 name[2] != ':' ||
1285 name[1] < '0' || '3' < name[1])
1286 cp = name + 1;
1287 else {
1288 stage = name[1] - '0';
1289 cp = name + 3;
1291 new_path = resolve_relative_path(cp);
1292 if (!new_path) {
1293 namelen = namelen - (cp - name);
1294 } else {
1295 cp = new_path;
1296 namelen = strlen(cp);
1299 strncpy(oc->path, cp,
1300 sizeof(oc->path));
1301 oc->path[sizeof(oc->path)-1] = '\0';
1303 if (!active_cache)
1304 read_cache();
1305 pos = cache_name_pos(cp, namelen);
1306 if (pos < 0)
1307 pos = -pos - 1;
1308 while (pos < active_nr) {
1309 ce = active_cache[pos];
1310 if (ce_namelen(ce) != namelen ||
1311 memcmp(ce->name, cp, namelen))
1312 break;
1313 if (ce_stage(ce) == stage) {
1314 hashcpy(sha1, ce->sha1);
1315 oc->mode = ce->ce_mode;
1316 free(new_path);
1317 return 0;
1319 pos++;
1321 if (only_to_die && name[1] && name[1] != '/')
1322 diagnose_invalid_index_path(stage, prefix, cp);
1323 free(new_path);
1324 return -1;
1326 for (cp = name, bracket_depth = 0; *cp; cp++) {
1327 if (*cp == '{')
1328 bracket_depth++;
1329 else if (bracket_depth && *cp == '}')
1330 bracket_depth--;
1331 else if (!bracket_depth && *cp == ':')
1332 break;
1334 if (*cp == ':') {
1335 unsigned char tree_sha1[20];
1336 int len = cp - name;
1337 if (!get_sha1_1(name, len, tree_sha1, GET_SHA1_TREEISH)) {
1338 const char *filename = cp+1;
1339 char *new_filename = NULL;
1341 new_filename = resolve_relative_path(filename);
1342 if (new_filename)
1343 filename = new_filename;
1344 ret = get_tree_entry(tree_sha1, filename, sha1, &oc->mode);
1345 if (ret && only_to_die) {
1346 diagnose_invalid_sha1_path(prefix, filename,
1347 tree_sha1,
1348 name, len);
1350 hashcpy(oc->tree, tree_sha1);
1351 strncpy(oc->path, filename,
1352 sizeof(oc->path));
1353 oc->path[sizeof(oc->path)-1] = '\0';
1355 free(new_filename);
1356 return ret;
1357 } else {
1358 if (only_to_die)
1359 die("Invalid object name '%.*s'.", len, name);
1362 return ret;
1366 * Call this function when you know "name" given by the end user must
1367 * name an object but it doesn't; the function _may_ die with a better
1368 * diagnostic message than "no such object 'name'", e.g. "Path 'doc' does not
1369 * exist in 'HEAD'" when given "HEAD:doc", or it may return in which case
1370 * you have a chance to diagnose the error further.
1372 void maybe_die_on_misspelt_object_name(const char *name, const char *prefix)
1374 struct object_context oc;
1375 unsigned char sha1[20];
1376 get_sha1_with_context_1(name, GET_SHA1_ONLY_TO_DIE, prefix, sha1, &oc);
1379 int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc)
1381 return get_sha1_with_context_1(str, flags, NULL, sha1, orc);