Merge branch 'maint'
[git/jnareb-git.git] / sha1_name.c
blobfaea58dc8c27de23e8fbaff17b39cb9e57708510
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 static int find_short_object_filename(int len, const char *name, unsigned char *sha1)
14 struct alternate_object_database *alt;
15 char hex[40];
16 int found = 0;
17 static struct alternate_object_database *fakeent;
19 if (!fakeent) {
20 const char *objdir = get_object_directory();
21 int objdir_len = strlen(objdir);
22 int entlen = objdir_len + 43;
23 fakeent = xmalloc(sizeof(*fakeent) + entlen);
24 memcpy(fakeent->base, objdir, objdir_len);
25 fakeent->name = fakeent->base + objdir_len + 1;
26 fakeent->name[-1] = '/';
28 fakeent->next = alt_odb_list;
30 sprintf(hex, "%.2s", name);
31 for (alt = fakeent; alt && found < 2; alt = alt->next) {
32 struct dirent *de;
33 DIR *dir;
34 sprintf(alt->name, "%.2s/", name);
35 dir = opendir(alt->base);
36 if (!dir)
37 continue;
38 while ((de = readdir(dir)) != NULL) {
39 if (strlen(de->d_name) != 38)
40 continue;
41 if (memcmp(de->d_name, name + 2, len - 2))
42 continue;
43 if (!found) {
44 memcpy(hex + 2, de->d_name, 38);
45 found++;
47 else if (memcmp(hex + 2, de->d_name, 38)) {
48 found = 2;
49 break;
52 closedir(dir);
54 if (found == 1)
55 return get_sha1_hex(hex, sha1) == 0;
56 return found;
59 static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
61 do {
62 if (*a != *b)
63 return 0;
64 a++;
65 b++;
66 len -= 2;
67 } while (len > 1);
68 if (len)
69 if ((*a ^ *b) & 0xf0)
70 return 0;
71 return 1;
74 static int find_short_packed_object(int len, const unsigned char *match, unsigned char *sha1)
76 struct packed_git *p;
77 const unsigned char *found_sha1 = NULL;
78 int found = 0;
80 prepare_packed_git();
81 for (p = packed_git; p && found < 2; p = p->next) {
82 uint32_t num, last;
83 uint32_t first = 0;
84 open_pack_index(p);
85 num = p->num_objects;
86 last = num;
87 while (first < last) {
88 uint32_t mid = (first + last) / 2;
89 const unsigned char *now;
90 int cmp;
92 now = nth_packed_object_sha1(p, mid);
93 cmp = hashcmp(match, now);
94 if (!cmp) {
95 first = mid;
96 break;
98 if (cmp > 0) {
99 first = mid+1;
100 continue;
102 last = mid;
104 if (first < num) {
105 const unsigned char *now, *next;
106 now = nth_packed_object_sha1(p, first);
107 if (match_sha(len, match, now)) {
108 next = nth_packed_object_sha1(p, first+1);
109 if (!next|| !match_sha(len, match, next)) {
110 /* unique within this pack */
111 if (!found) {
112 found_sha1 = now;
113 found++;
115 else if (hashcmp(found_sha1, now)) {
116 found = 2;
117 break;
120 else {
121 /* not even unique within this pack */
122 found = 2;
123 break;
128 if (found == 1)
129 hashcpy(sha1, found_sha1);
130 return found;
133 #define SHORT_NAME_NOT_FOUND (-1)
134 #define SHORT_NAME_AMBIGUOUS (-2)
136 static int find_unique_short_object(int len, char *canonical,
137 unsigned char *res, unsigned char *sha1)
139 int has_unpacked, has_packed;
140 unsigned char unpacked_sha1[20], packed_sha1[20];
142 prepare_alt_odb();
143 has_unpacked = find_short_object_filename(len, canonical, unpacked_sha1);
144 has_packed = find_short_packed_object(len, res, packed_sha1);
145 if (!has_unpacked && !has_packed)
146 return SHORT_NAME_NOT_FOUND;
147 if (1 < has_unpacked || 1 < has_packed)
148 return SHORT_NAME_AMBIGUOUS;
149 if (has_unpacked != has_packed) {
150 hashcpy(sha1, (has_packed ? packed_sha1 : unpacked_sha1));
151 return 0;
153 /* Both have unique ones -- do they match? */
154 if (hashcmp(packed_sha1, unpacked_sha1))
155 return SHORT_NAME_AMBIGUOUS;
156 hashcpy(sha1, packed_sha1);
157 return 0;
160 static int get_short_sha1(const char *name, int len, unsigned char *sha1,
161 int quietly)
163 int i, status;
164 char canonical[40];
165 unsigned char res[20];
167 if (len < MINIMUM_ABBREV || len > 40)
168 return -1;
169 hashclr(res);
170 memset(canonical, 'x', 40);
171 for (i = 0; i < len ;i++) {
172 unsigned char c = name[i];
173 unsigned char val;
174 if (c >= '0' && c <= '9')
175 val = c - '0';
176 else if (c >= 'a' && c <= 'f')
177 val = c - 'a' + 10;
178 else if (c >= 'A' && c <='F') {
179 val = c - 'A' + 10;
180 c -= 'A' - 'a';
182 else
183 return -1;
184 canonical[i] = c;
185 if (!(i & 1))
186 val <<= 4;
187 res[i >> 1] |= val;
190 status = find_unique_short_object(i, canonical, res, sha1);
191 if (!quietly && (status == SHORT_NAME_AMBIGUOUS))
192 return error("short SHA1 %.*s is ambiguous.", len, canonical);
193 return status;
196 const char *find_unique_abbrev(const unsigned char *sha1, int len)
198 int status, exists;
199 static char hex[41];
201 exists = has_sha1_file(sha1);
202 memcpy(hex, sha1_to_hex(sha1), 40);
203 if (len == 40 || !len)
204 return hex;
205 while (len < 40) {
206 unsigned char sha1_ret[20];
207 status = get_short_sha1(hex, len, sha1_ret, 1);
208 if (exists
209 ? !status
210 : status == SHORT_NAME_NOT_FOUND) {
211 hex[len] = 0;
212 return hex;
214 len++;
216 return hex;
219 static int ambiguous_path(const char *path, int len)
221 int slash = 1;
222 int cnt;
224 for (cnt = 0; cnt < len; cnt++) {
225 switch (*path++) {
226 case '\0':
227 break;
228 case '/':
229 if (slash)
230 break;
231 slash = 1;
232 continue;
233 case '.':
234 continue;
235 default:
236 slash = 0;
237 continue;
239 break;
241 return slash;
245 * *string and *len will only be substituted, and *string returned (for
246 * later free()ing) if the string passed in is a magic short-hand form
247 * to name a branch.
249 static char *substitute_branch_name(const char **string, int *len)
251 struct strbuf buf = STRBUF_INIT;
252 int ret = interpret_branch_name(*string, &buf);
254 if (ret == *len) {
255 size_t size;
256 *string = strbuf_detach(&buf, &size);
257 *len = size;
258 return (char *)*string;
261 return NULL;
264 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
266 char *last_branch = substitute_branch_name(&str, &len);
267 const char **p, *r;
268 int refs_found = 0;
270 *ref = NULL;
271 for (p = ref_rev_parse_rules; *p; p++) {
272 char fullref[PATH_MAX];
273 unsigned char sha1_from_ref[20];
274 unsigned char *this_result;
275 int flag;
277 this_result = refs_found ? sha1_from_ref : sha1;
278 mksnpath(fullref, sizeof(fullref), *p, len, str);
279 r = resolve_ref(fullref, this_result, 1, &flag);
280 if (r) {
281 if (!refs_found++)
282 *ref = xstrdup(r);
283 if (!warn_ambiguous_refs)
284 break;
285 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD"))
286 warning("ignoring dangling symref %s.", fullref);
288 free(last_branch);
289 return refs_found;
292 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
294 char *last_branch = substitute_branch_name(&str, &len);
295 const char **p;
296 int logs_found = 0;
298 *log = NULL;
299 for (p = ref_rev_parse_rules; *p; p++) {
300 struct stat st;
301 unsigned char hash[20];
302 char path[PATH_MAX];
303 const char *ref, *it;
305 mksnpath(path, sizeof(path), *p, len, str);
306 ref = resolve_ref(path, hash, 1, NULL);
307 if (!ref)
308 continue;
309 if (!stat(git_path("logs/%s", path), &st) &&
310 S_ISREG(st.st_mode))
311 it = path;
312 else if (strcmp(ref, path) &&
313 !stat(git_path("logs/%s", ref), &st) &&
314 S_ISREG(st.st_mode))
315 it = ref;
316 else
317 continue;
318 if (!logs_found++) {
319 *log = xstrdup(it);
320 hashcpy(sha1, hash);
322 if (!warn_ambiguous_refs)
323 break;
325 free(last_branch);
326 return logs_found;
329 static inline int upstream_mark(const char *string, int len)
331 const char *suffix[] = { "@{upstream}", "@{u}" };
332 int i;
334 for (i = 0; i < ARRAY_SIZE(suffix); i++) {
335 int suffix_len = strlen(suffix[i]);
336 if (suffix_len <= len
337 && !memcmp(string, suffix[i], suffix_len))
338 return suffix_len;
340 return 0;
343 static int get_sha1_1(const char *name, int len, unsigned char *sha1);
345 static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
347 static const char *warn_msg = "refname '%.*s' is ambiguous.";
348 char *real_ref = NULL;
349 int refs_found = 0;
350 int at, reflog_len;
352 if (len == 40 && !get_sha1_hex(str, sha1))
353 return 0;
355 /* basic@{time or number or -number} format to query ref-log */
356 reflog_len = at = 0;
357 if (len && str[len-1] == '}') {
358 for (at = len-2; at >= 0; at--) {
359 if (str[at] == '@' && str[at+1] == '{') {
360 if (!upstream_mark(str + at, len - at)) {
361 reflog_len = (len-1) - (at+2);
362 len = at;
364 break;
369 /* Accept only unambiguous ref paths. */
370 if (len && ambiguous_path(str, len))
371 return -1;
373 if (!len && reflog_len) {
374 struct strbuf buf = STRBUF_INIT;
375 int ret;
376 /* try the @{-N} syntax for n-th checkout */
377 ret = interpret_branch_name(str+at, &buf);
378 if (ret > 0) {
379 /* substitute this branch name and restart */
380 return get_sha1_1(buf.buf, buf.len, sha1);
381 } else if (ret == 0) {
382 return -1;
384 /* allow "@{...}" to mean the current branch reflog */
385 refs_found = dwim_ref("HEAD", 4, sha1, &real_ref);
386 } else if (reflog_len)
387 refs_found = dwim_log(str, len, sha1, &real_ref);
388 else
389 refs_found = dwim_ref(str, len, sha1, &real_ref);
391 if (!refs_found)
392 return -1;
394 if (warn_ambiguous_refs && refs_found > 1)
395 warning(warn_msg, len, str);
397 if (reflog_len) {
398 int nth, i;
399 unsigned long at_time;
400 unsigned long co_time;
401 int co_tz, co_cnt;
403 /* a @{-N} placed anywhere except the start is an error */
404 if (str[at+2] == '-')
405 return -1;
407 /* Is it asking for N-th entry, or approxidate? */
408 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
409 char ch = str[at+2+i];
410 if ('0' <= ch && ch <= '9')
411 nth = nth * 10 + ch - '0';
412 else
413 nth = -1;
415 if (100000000 <= nth) {
416 at_time = nth;
417 nth = -1;
418 } else if (0 <= nth)
419 at_time = 0;
420 else {
421 int errors = 0;
422 char *tmp = xstrndup(str + at + 2, reflog_len);
423 at_time = approxidate_careful(tmp, &errors);
424 free(tmp);
425 if (errors)
426 return -1;
428 if (read_ref_at(real_ref, at_time, nth, sha1, NULL,
429 &co_time, &co_tz, &co_cnt)) {
430 if (at_time)
431 warning("Log for '%.*s' only goes "
432 "back to %s.", len, str,
433 show_date(co_time, co_tz, DATE_RFC2822));
434 else {
435 free(real_ref);
436 die("Log for '%.*s' only has %d entries.",
437 len, str, co_cnt);
442 free(real_ref);
443 return 0;
446 static int get_parent(const char *name, int len,
447 unsigned char *result, int idx)
449 unsigned char sha1[20];
450 int ret = get_sha1_1(name, len, sha1);
451 struct commit *commit;
452 struct commit_list *p;
454 if (ret)
455 return ret;
456 commit = lookup_commit_reference(sha1);
457 if (!commit)
458 return -1;
459 if (parse_commit(commit))
460 return -1;
461 if (!idx) {
462 hashcpy(result, commit->object.sha1);
463 return 0;
465 p = commit->parents;
466 while (p) {
467 if (!--idx) {
468 hashcpy(result, p->item->object.sha1);
469 return 0;
471 p = p->next;
473 return -1;
476 static int get_nth_ancestor(const char *name, int len,
477 unsigned char *result, int generation)
479 unsigned char sha1[20];
480 struct commit *commit;
481 int ret;
483 ret = get_sha1_1(name, len, sha1);
484 if (ret)
485 return ret;
486 commit = lookup_commit_reference(sha1);
487 if (!commit)
488 return -1;
490 while (generation--) {
491 if (parse_commit(commit) || !commit->parents)
492 return -1;
493 commit = commit->parents->item;
495 hashcpy(result, commit->object.sha1);
496 return 0;
499 struct object *peel_to_type(const char *name, int namelen,
500 struct object *o, enum object_type expected_type)
502 if (name && !namelen)
503 namelen = strlen(name);
504 if (!o) {
505 unsigned char sha1[20];
506 if (get_sha1_1(name, namelen, sha1))
507 return NULL;
508 o = parse_object(sha1);
510 while (1) {
511 if (!o || (!o->parsed && !parse_object(o->sha1)))
512 return NULL;
513 if (o->type == expected_type)
514 return o;
515 if (o->type == OBJ_TAG)
516 o = ((struct tag*) o)->tagged;
517 else if (o->type == OBJ_COMMIT)
518 o = &(((struct commit *) o)->tree->object);
519 else {
520 if (name)
521 error("%.*s: expected %s type, but the object "
522 "dereferences to %s type",
523 namelen, name, typename(expected_type),
524 typename(o->type));
525 return NULL;
530 static int peel_onion(const char *name, int len, unsigned char *sha1)
532 unsigned char outer[20];
533 const char *sp;
534 unsigned int expected_type = 0;
535 struct object *o;
538 * "ref^{type}" dereferences ref repeatedly until you cannot
539 * dereference anymore, or you get an object of given type,
540 * whichever comes first. "ref^{}" means just dereference
541 * tags until you get a non-tag. "ref^0" is a shorthand for
542 * "ref^{commit}". "commit^{tree}" could be used to find the
543 * top-level tree of the given commit.
545 if (len < 4 || name[len-1] != '}')
546 return -1;
548 for (sp = name + len - 1; name <= sp; sp--) {
549 int ch = *sp;
550 if (ch == '{' && name < sp && sp[-1] == '^')
551 break;
553 if (sp <= name)
554 return -1;
556 sp++; /* beginning of type name, or closing brace for empty */
557 if (!strncmp(commit_type, sp, 6) && sp[6] == '}')
558 expected_type = OBJ_COMMIT;
559 else if (!strncmp(tree_type, sp, 4) && sp[4] == '}')
560 expected_type = OBJ_TREE;
561 else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
562 expected_type = OBJ_BLOB;
563 else if (sp[0] == '}')
564 expected_type = OBJ_NONE;
565 else if (sp[0] == '/')
566 expected_type = OBJ_COMMIT;
567 else
568 return -1;
570 if (get_sha1_1(name, sp - name - 2, outer))
571 return -1;
573 o = parse_object(outer);
574 if (!o)
575 return -1;
576 if (!expected_type) {
577 o = deref_tag(o, name, sp - name - 2);
578 if (!o || (!o->parsed && !parse_object(o->sha1)))
579 return -1;
580 hashcpy(sha1, o->sha1);
581 return 0;
585 * At this point, the syntax look correct, so
586 * if we do not get the needed object, we should
587 * barf.
589 o = peel_to_type(name, len, o, expected_type);
590 if (!o)
591 return -1;
593 hashcpy(sha1, o->sha1);
594 if (sp[0] == '/') {
595 /* "$commit^{/foo}" */
596 char *prefix;
597 int ret;
598 struct commit_list *list = NULL;
601 * $commit^{/}. Some regex implementation may reject.
602 * We don't need regex anyway. '' pattern always matches.
604 if (sp[1] == '}')
605 return 0;
607 prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
608 commit_list_insert((struct commit *)o, &list);
609 ret = get_sha1_oneline(prefix, sha1, list);
610 free(prefix);
611 return ret;
613 return 0;
616 static int get_describe_name(const char *name, int len, unsigned char *sha1)
618 const char *cp;
620 for (cp = name + len - 1; name + 2 <= cp; cp--) {
621 char ch = *cp;
622 if (hexval(ch) & ~0377) {
623 /* We must be looking at g in "SOMETHING-g"
624 * for it to be describe output.
626 if (ch == 'g' && cp[-1] == '-') {
627 cp++;
628 len -= cp - name;
629 return get_short_sha1(cp, len, sha1, 1);
633 return -1;
636 static int get_sha1_1(const char *name, int len, unsigned char *sha1)
638 int ret, has_suffix;
639 const char *cp;
642 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
644 has_suffix = 0;
645 for (cp = name + len - 1; name <= cp; cp--) {
646 int ch = *cp;
647 if ('0' <= ch && ch <= '9')
648 continue;
649 if (ch == '~' || ch == '^')
650 has_suffix = ch;
651 break;
654 if (has_suffix) {
655 int num = 0;
656 int len1 = cp - name;
657 cp++;
658 while (cp < name + len)
659 num = num * 10 + *cp++ - '0';
660 if (!num && len1 == len - 1)
661 num = 1;
662 if (has_suffix == '^')
663 return get_parent(name, len1, sha1, num);
664 /* else if (has_suffix == '~') -- goes without saying */
665 return get_nth_ancestor(name, len1, sha1, num);
668 ret = peel_onion(name, len, sha1);
669 if (!ret)
670 return 0;
672 ret = get_sha1_basic(name, len, sha1);
673 if (!ret)
674 return 0;
676 /* It could be describe output that is "SOMETHING-gXXXX" */
677 ret = get_describe_name(name, len, sha1);
678 if (!ret)
679 return 0;
681 return get_short_sha1(name, len, sha1, 0);
685 * This interprets names like ':/Initial revision of "git"' by searching
686 * through history and returning the first commit whose message starts
687 * the given regular expression.
689 * For future extension, ':/!' is reserved. If you want to match a message
690 * beginning with a '!', you have to repeat the exclamation mark.
692 #define ONELINE_SEEN (1u<<20)
694 static int handle_one_ref(const char *path,
695 const unsigned char *sha1, int flag, void *cb_data)
697 struct commit_list **list = cb_data;
698 struct object *object = parse_object(sha1);
699 if (!object)
700 return 0;
701 if (object->type == OBJ_TAG) {
702 object = deref_tag(object, path, strlen(path));
703 if (!object)
704 return 0;
706 if (object->type != OBJ_COMMIT)
707 return 0;
708 commit_list_insert_by_date((struct commit *)object, list);
709 return 0;
712 static int get_sha1_oneline(const char *prefix, unsigned char *sha1,
713 struct commit_list *list)
715 struct commit_list *backup = NULL, *l;
716 int found = 0;
717 regex_t regex;
719 if (prefix[0] == '!') {
720 if (prefix[1] != '!')
721 die ("Invalid search pattern: %s", prefix);
722 prefix++;
725 if (regcomp(&regex, prefix, REG_EXTENDED))
726 die("Invalid search pattern: %s", prefix);
728 for (l = list; l; l = l->next) {
729 l->item->object.flags |= ONELINE_SEEN;
730 commit_list_insert(l->item, &backup);
732 while (list) {
733 char *p, *to_free = NULL;
734 struct commit *commit;
735 enum object_type type;
736 unsigned long size;
737 int matches;
739 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
740 if (!parse_object(commit->object.sha1))
741 continue;
742 if (commit->buffer)
743 p = commit->buffer;
744 else {
745 p = read_sha1_file(commit->object.sha1, &type, &size);
746 if (!p)
747 continue;
748 to_free = p;
751 p = strstr(p, "\n\n");
752 matches = p && !regexec(&regex, p + 2, 0, NULL, 0);
753 free(to_free);
755 if (matches) {
756 hashcpy(sha1, commit->object.sha1);
757 found = 1;
758 break;
761 regfree(&regex);
762 free_commit_list(list);
763 for (l = backup; l; l = l->next)
764 clear_commit_marks(l->item, ONELINE_SEEN);
765 free_commit_list(backup);
766 return found ? 0 : -1;
769 struct grab_nth_branch_switch_cbdata {
770 long cnt, alloc;
771 struct strbuf *buf;
774 static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
775 const char *email, unsigned long timestamp, int tz,
776 const char *message, void *cb_data)
778 struct grab_nth_branch_switch_cbdata *cb = cb_data;
779 const char *match = NULL, *target = NULL;
780 size_t len;
781 int nth;
783 if (!prefixcmp(message, "checkout: moving from ")) {
784 match = message + strlen("checkout: moving from ");
785 target = strstr(match, " to ");
788 if (!match || !target)
789 return 0;
791 len = target - match;
792 nth = cb->cnt++ % cb->alloc;
793 strbuf_reset(&cb->buf[nth]);
794 strbuf_add(&cb->buf[nth], match, len);
795 return 0;
799 * Parse @{-N} syntax, return the number of characters parsed
800 * if successful; otherwise signal an error with negative value.
802 static int interpret_nth_prior_checkout(const char *name, struct strbuf *buf)
804 long nth;
805 int i, retval;
806 struct grab_nth_branch_switch_cbdata cb;
807 const char *brace;
808 char *num_end;
810 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
811 return -1;
812 brace = strchr(name, '}');
813 if (!brace)
814 return -1;
815 nth = strtol(name+3, &num_end, 10);
816 if (num_end != brace)
817 return -1;
818 if (nth <= 0)
819 return -1;
820 cb.alloc = nth;
821 cb.buf = xmalloc(nth * sizeof(struct strbuf));
822 for (i = 0; i < nth; i++)
823 strbuf_init(&cb.buf[i], 20);
824 cb.cnt = 0;
825 retval = 0;
826 for_each_recent_reflog_ent("HEAD", grab_nth_branch_switch, 40960, &cb);
827 if (cb.cnt < nth) {
828 cb.cnt = 0;
829 for_each_reflog_ent("HEAD", grab_nth_branch_switch, &cb);
831 if (cb.cnt < nth)
832 goto release_return;
833 i = cb.cnt % nth;
834 strbuf_reset(buf);
835 strbuf_add(buf, cb.buf[i].buf, cb.buf[i].len);
836 retval = brace-name+1;
838 release_return:
839 for (i = 0; i < nth; i++)
840 strbuf_release(&cb.buf[i]);
841 free(cb.buf);
843 return retval;
846 int get_sha1_mb(const char *name, unsigned char *sha1)
848 struct commit *one, *two;
849 struct commit_list *mbs;
850 unsigned char sha1_tmp[20];
851 const char *dots;
852 int st;
854 dots = strstr(name, "...");
855 if (!dots)
856 return get_sha1(name, sha1);
857 if (dots == name)
858 st = get_sha1("HEAD", sha1_tmp);
859 else {
860 struct strbuf sb;
861 strbuf_init(&sb, dots - name);
862 strbuf_add(&sb, name, dots - name);
863 st = get_sha1(sb.buf, sha1_tmp);
864 strbuf_release(&sb);
866 if (st)
867 return st;
868 one = lookup_commit_reference_gently(sha1_tmp, 0);
869 if (!one)
870 return -1;
872 if (get_sha1(dots[3] ? (dots + 3) : "HEAD", sha1_tmp))
873 return -1;
874 two = lookup_commit_reference_gently(sha1_tmp, 0);
875 if (!two)
876 return -1;
877 mbs = get_merge_bases(one, two, 1);
878 if (!mbs || mbs->next)
879 st = -1;
880 else {
881 st = 0;
882 hashcpy(sha1, mbs->item->object.sha1);
884 free_commit_list(mbs);
885 return st;
889 * This reads short-hand syntax that not only evaluates to a commit
890 * object name, but also can act as if the end user spelled the name
891 * of the branch from the command line.
893 * - "@{-N}" finds the name of the Nth previous branch we were on, and
894 * places the name of the branch in the given buf and returns the
895 * number of characters parsed if successful.
897 * - "<branch>@{upstream}" finds the name of the other ref that
898 * <branch> is configured to merge with (missing <branch> defaults
899 * to the current branch), and places the name of the branch in the
900 * given buf and returns the number of characters parsed if
901 * successful.
903 * If the input is not of the accepted format, it returns a negative
904 * number to signal an error.
906 * If the input was ok but there are not N branch switches in the
907 * reflog, it returns 0.
909 int interpret_branch_name(const char *name, struct strbuf *buf)
911 char *cp;
912 struct branch *upstream;
913 int namelen = strlen(name);
914 int len = interpret_nth_prior_checkout(name, buf);
915 int tmp_len;
917 if (!len)
918 return len; /* syntax Ok, not enough switches */
919 if (0 < len && len == namelen)
920 return len; /* consumed all */
921 else if (0 < len) {
922 /* we have extra data, which might need further processing */
923 struct strbuf tmp = STRBUF_INIT;
924 int used = buf->len;
925 int ret;
927 strbuf_add(buf, name + len, namelen - len);
928 ret = interpret_branch_name(buf->buf, &tmp);
929 /* that data was not interpreted, remove our cruft */
930 if (ret < 0) {
931 strbuf_setlen(buf, used);
932 return len;
934 strbuf_reset(buf);
935 strbuf_addbuf(buf, &tmp);
936 strbuf_release(&tmp);
937 /* tweak for size of {-N} versus expanded ref name */
938 return ret - used + len;
941 cp = strchr(name, '@');
942 if (!cp)
943 return -1;
944 tmp_len = upstream_mark(cp, namelen - (cp - name));
945 if (!tmp_len)
946 return -1;
947 len = cp + tmp_len - name;
948 cp = xstrndup(name, cp - name);
949 upstream = branch_get(*cp ? cp : NULL);
950 if (!upstream
951 || !upstream->merge
952 || !upstream->merge[0]->dst)
953 return error("No upstream branch found for '%s'", cp);
954 free(cp);
955 cp = shorten_unambiguous_ref(upstream->merge[0]->dst, 0);
956 strbuf_reset(buf);
957 strbuf_addstr(buf, cp);
958 free(cp);
959 return len;
962 int strbuf_branchname(struct strbuf *sb, const char *name)
964 int len = strlen(name);
965 if (interpret_branch_name(name, sb) == len)
966 return 0;
967 strbuf_add(sb, name, len);
968 return len;
971 int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
973 strbuf_branchname(sb, name);
974 if (name[0] == '-')
975 return CHECK_REF_FORMAT_ERROR;
976 strbuf_splice(sb, 0, 0, "refs/heads/", 11);
977 return check_ref_format(sb->buf);
981 * This is like "get_sha1_basic()", except it allows "sha1 expressions",
982 * notably "xyz^" for "parent of xyz"
984 int get_sha1(const char *name, unsigned char *sha1)
986 struct object_context unused;
987 return get_sha1_with_context(name, sha1, &unused);
990 /* Must be called only when object_name:filename doesn't exist. */
991 static void diagnose_invalid_sha1_path(const char *prefix,
992 const char *filename,
993 const unsigned char *tree_sha1,
994 const char *object_name)
996 struct stat st;
997 unsigned char sha1[20];
998 unsigned mode;
1000 if (!prefix)
1001 prefix = "";
1003 if (!lstat(filename, &st))
1004 die("Path '%s' exists on disk, but not in '%s'.",
1005 filename, object_name);
1006 if (errno == ENOENT || errno == ENOTDIR) {
1007 char *fullname = xmalloc(strlen(filename)
1008 + strlen(prefix) + 1);
1009 strcpy(fullname, prefix);
1010 strcat(fullname, filename);
1012 if (!get_tree_entry(tree_sha1, fullname,
1013 sha1, &mode)) {
1014 die("Path '%s' exists, but not '%s'.\n"
1015 "Did you mean '%s:%s'?",
1016 fullname,
1017 filename,
1018 object_name,
1019 fullname);
1021 die("Path '%s' does not exist in '%s'",
1022 filename, object_name);
1026 /* Must be called only when :stage:filename doesn't exist. */
1027 static void diagnose_invalid_index_path(int stage,
1028 const char *prefix,
1029 const char *filename)
1031 struct stat st;
1032 struct cache_entry *ce;
1033 int pos;
1034 unsigned namelen = strlen(filename);
1035 unsigned fullnamelen;
1036 char *fullname;
1038 if (!prefix)
1039 prefix = "";
1041 /* Wrong stage number? */
1042 pos = cache_name_pos(filename, namelen);
1043 if (pos < 0)
1044 pos = -pos - 1;
1045 if (pos < active_nr) {
1046 ce = active_cache[pos];
1047 if (ce_namelen(ce) == namelen &&
1048 !memcmp(ce->name, filename, namelen))
1049 die("Path '%s' is in the index, but not at stage %d.\n"
1050 "Did you mean ':%d:%s'?",
1051 filename, stage,
1052 ce_stage(ce), filename);
1055 /* Confusion between relative and absolute filenames? */
1056 fullnamelen = namelen + strlen(prefix);
1057 fullname = xmalloc(fullnamelen + 1);
1058 strcpy(fullname, prefix);
1059 strcat(fullname, filename);
1060 pos = cache_name_pos(fullname, fullnamelen);
1061 if (pos < 0)
1062 pos = -pos - 1;
1063 if (pos < active_nr) {
1064 ce = active_cache[pos];
1065 if (ce_namelen(ce) == fullnamelen &&
1066 !memcmp(ce->name, fullname, fullnamelen))
1067 die("Path '%s' is in the index, but not '%s'.\n"
1068 "Did you mean ':%d:%s'?",
1069 fullname, filename,
1070 ce_stage(ce), fullname);
1073 if (!lstat(filename, &st))
1074 die("Path '%s' exists on disk, but not in the index.", filename);
1075 if (errno == ENOENT || errno == ENOTDIR)
1076 die("Path '%s' does not exist (neither on disk nor in the index).",
1077 filename);
1079 free(fullname);
1083 int get_sha1_with_mode_1(const char *name, unsigned char *sha1, unsigned *mode, int gently, const char *prefix)
1085 struct object_context oc;
1086 int ret;
1087 ret = get_sha1_with_context_1(name, sha1, &oc, gently, prefix);
1088 *mode = oc.mode;
1089 return ret;
1092 static char *resolve_relative_path(const char *rel)
1094 if (prefixcmp(rel, "./") && prefixcmp(rel, "../"))
1095 return NULL;
1097 if (!startup_info)
1098 die("BUG: startup_info struct is not initialized.");
1100 if (!is_inside_work_tree())
1101 die("relative path syntax can't be used outside working tree.");
1103 /* die() inside prefix_path() if resolved path is outside worktree */
1104 return prefix_path(startup_info->prefix,
1105 startup_info->prefix ? strlen(startup_info->prefix) : 0,
1106 rel);
1109 int get_sha1_with_context_1(const char *name, unsigned char *sha1,
1110 struct object_context *oc,
1111 int gently, const char *prefix)
1113 int ret, bracket_depth;
1114 int namelen = strlen(name);
1115 const char *cp;
1117 memset(oc, 0, sizeof(*oc));
1118 oc->mode = S_IFINVALID;
1119 ret = get_sha1_1(name, namelen, sha1);
1120 if (!ret)
1121 return ret;
1122 /* sha1:path --> object name of path in ent sha1
1123 * :path -> object name of absolute path in index
1124 * :./path -> object name of path relative to cwd in index
1125 * :[0-3]:path -> object name of path in index at stage
1126 * :/foo -> recent commit matching foo
1128 if (name[0] == ':') {
1129 int stage = 0;
1130 struct cache_entry *ce;
1131 char *new_path = NULL;
1132 int pos;
1133 if (namelen > 2 && name[1] == '/') {
1134 struct commit_list *list = NULL;
1135 for_each_ref(handle_one_ref, &list);
1136 return get_sha1_oneline(name + 2, sha1, list);
1138 if (namelen < 3 ||
1139 name[2] != ':' ||
1140 name[1] < '0' || '3' < name[1])
1141 cp = name + 1;
1142 else {
1143 stage = name[1] - '0';
1144 cp = name + 3;
1146 new_path = resolve_relative_path(cp);
1147 if (!new_path) {
1148 namelen = namelen - (cp - name);
1149 } else {
1150 cp = new_path;
1151 namelen = strlen(cp);
1154 strncpy(oc->path, cp,
1155 sizeof(oc->path));
1156 oc->path[sizeof(oc->path)-1] = '\0';
1158 if (!active_cache)
1159 read_cache();
1160 pos = cache_name_pos(cp, namelen);
1161 if (pos < 0)
1162 pos = -pos - 1;
1163 while (pos < active_nr) {
1164 ce = active_cache[pos];
1165 if (ce_namelen(ce) != namelen ||
1166 memcmp(ce->name, cp, namelen))
1167 break;
1168 if (ce_stage(ce) == stage) {
1169 hashcpy(sha1, ce->sha1);
1170 oc->mode = ce->ce_mode;
1171 free(new_path);
1172 return 0;
1174 pos++;
1176 if (!gently)
1177 diagnose_invalid_index_path(stage, prefix, cp);
1178 free(new_path);
1179 return -1;
1181 for (cp = name, bracket_depth = 0; *cp; cp++) {
1182 if (*cp == '{')
1183 bracket_depth++;
1184 else if (bracket_depth && *cp == '}')
1185 bracket_depth--;
1186 else if (!bracket_depth && *cp == ':')
1187 break;
1189 if (*cp == ':') {
1190 unsigned char tree_sha1[20];
1191 char *object_name = NULL;
1192 if (!gently) {
1193 object_name = xmalloc(cp-name+1);
1194 strncpy(object_name, name, cp-name);
1195 object_name[cp-name] = '\0';
1197 if (!get_sha1_1(name, cp-name, tree_sha1)) {
1198 const char *filename = cp+1;
1199 char *new_filename = NULL;
1201 new_filename = resolve_relative_path(filename);
1202 if (new_filename)
1203 filename = new_filename;
1204 ret = get_tree_entry(tree_sha1, filename, sha1, &oc->mode);
1205 if (!gently) {
1206 diagnose_invalid_sha1_path(prefix, filename,
1207 tree_sha1, object_name);
1208 free(object_name);
1210 hashcpy(oc->tree, tree_sha1);
1211 strncpy(oc->path, filename,
1212 sizeof(oc->path));
1213 oc->path[sizeof(oc->path)-1] = '\0';
1215 free(new_filename);
1216 return ret;
1217 } else {
1218 if (!gently)
1219 die("Invalid object name '%s'.", object_name);
1222 return ret;