submodule: Use cat instead of echo to avoid DOS line-endings
[git/dscho.git] / sha1_name.c
blobba976b48398d4be0635746bcabb5b1c881e77ae8
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 while (1) {
505 if (!o || (!o->parsed && !parse_object(o->sha1)))
506 return NULL;
507 if (o->type == expected_type)
508 return o;
509 if (o->type == OBJ_TAG)
510 o = ((struct tag*) o)->tagged;
511 else if (o->type == OBJ_COMMIT)
512 o = &(((struct commit *) o)->tree->object);
513 else {
514 if (name)
515 error("%.*s: expected %s type, but the object "
516 "dereferences to %s type",
517 namelen, name, typename(expected_type),
518 typename(o->type));
519 return NULL;
524 static int peel_onion(const char *name, int len, unsigned char *sha1)
526 unsigned char outer[20];
527 const char *sp;
528 unsigned int expected_type = 0;
529 struct object *o;
532 * "ref^{type}" dereferences ref repeatedly until you cannot
533 * dereference anymore, or you get an object of given type,
534 * whichever comes first. "ref^{}" means just dereference
535 * tags until you get a non-tag. "ref^0" is a shorthand for
536 * "ref^{commit}". "commit^{tree}" could be used to find the
537 * top-level tree of the given commit.
539 if (len < 4 || name[len-1] != '}')
540 return -1;
542 for (sp = name + len - 1; name <= sp; sp--) {
543 int ch = *sp;
544 if (ch == '{' && name < sp && sp[-1] == '^')
545 break;
547 if (sp <= name)
548 return -1;
550 sp++; /* beginning of type name, or closing brace for empty */
551 if (!strncmp(commit_type, sp, 6) && sp[6] == '}')
552 expected_type = OBJ_COMMIT;
553 else if (!strncmp(tree_type, sp, 4) && sp[4] == '}')
554 expected_type = OBJ_TREE;
555 else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
556 expected_type = OBJ_BLOB;
557 else if (sp[0] == '}')
558 expected_type = OBJ_NONE;
559 else if (sp[0] == '/')
560 expected_type = OBJ_COMMIT;
561 else
562 return -1;
564 if (get_sha1_1(name, sp - name - 2, outer))
565 return -1;
567 o = parse_object(outer);
568 if (!o)
569 return -1;
570 if (!expected_type) {
571 o = deref_tag(o, name, sp - name - 2);
572 if (!o || (!o->parsed && !parse_object(o->sha1)))
573 return -1;
574 hashcpy(sha1, o->sha1);
575 return 0;
579 * At this point, the syntax look correct, so
580 * if we do not get the needed object, we should
581 * barf.
583 o = peel_to_type(name, len, o, expected_type);
584 if (!o)
585 return -1;
587 hashcpy(sha1, o->sha1);
588 if (sp[0] == '/') {
589 /* "$commit^{/foo}" */
590 char *prefix;
591 int ret;
592 struct commit_list *list = NULL;
595 * $commit^{/}. Some regex implementation may reject.
596 * We don't need regex anyway. '' pattern always matches.
598 if (sp[1] == '}')
599 return 0;
601 prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
602 commit_list_insert((struct commit *)o, &list);
603 ret = get_sha1_oneline(prefix, sha1, list);
604 free(prefix);
605 return ret;
607 return 0;
610 static int get_describe_name(const char *name, int len, unsigned char *sha1)
612 const char *cp;
614 for (cp = name + len - 1; name + 2 <= cp; cp--) {
615 char ch = *cp;
616 if (hexval(ch) & ~0377) {
617 /* We must be looking at g in "SOMETHING-g"
618 * for it to be describe output.
620 if (ch == 'g' && cp[-1] == '-') {
621 cp++;
622 len -= cp - name;
623 return get_short_sha1(cp, len, sha1, 1);
627 return -1;
630 static int get_sha1_1(const char *name, int len, unsigned char *sha1)
632 int ret, has_suffix;
633 const char *cp;
636 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
638 has_suffix = 0;
639 for (cp = name + len - 1; name <= cp; cp--) {
640 int ch = *cp;
641 if ('0' <= ch && ch <= '9')
642 continue;
643 if (ch == '~' || ch == '^')
644 has_suffix = ch;
645 break;
648 if (has_suffix) {
649 int num = 0;
650 int len1 = cp - name;
651 cp++;
652 while (cp < name + len)
653 num = num * 10 + *cp++ - '0';
654 if (!num && len1 == len - 1)
655 num = 1;
656 if (has_suffix == '^')
657 return get_parent(name, len1, sha1, num);
658 /* else if (has_suffix == '~') -- goes without saying */
659 return get_nth_ancestor(name, len1, sha1, num);
662 ret = peel_onion(name, len, sha1);
663 if (!ret)
664 return 0;
666 ret = get_sha1_basic(name, len, sha1);
667 if (!ret)
668 return 0;
670 /* It could be describe output that is "SOMETHING-gXXXX" */
671 ret = get_describe_name(name, len, sha1);
672 if (!ret)
673 return 0;
675 return get_short_sha1(name, len, sha1, 0);
679 * This interprets names like ':/Initial revision of "git"' by searching
680 * through history and returning the first commit whose message starts
681 * the given regular expression.
683 * For future extension, ':/!' is reserved. If you want to match a message
684 * beginning with a '!', you have to repeat the exclamation mark.
686 #define ONELINE_SEEN (1u<<20)
688 static int handle_one_ref(const char *path,
689 const unsigned char *sha1, int flag, void *cb_data)
691 struct commit_list **list = cb_data;
692 struct object *object = parse_object(sha1);
693 if (!object)
694 return 0;
695 if (object->type == OBJ_TAG) {
696 object = deref_tag(object, path, strlen(path));
697 if (!object)
698 return 0;
700 if (object->type != OBJ_COMMIT)
701 return 0;
702 commit_list_insert_by_date((struct commit *)object, list);
703 return 0;
706 static int get_sha1_oneline(const char *prefix, unsigned char *sha1,
707 struct commit_list *list)
709 struct commit_list *backup = NULL, *l;
710 int found = 0;
711 regex_t regex;
713 if (prefix[0] == '!') {
714 if (prefix[1] != '!')
715 die ("Invalid search pattern: %s", prefix);
716 prefix++;
719 if (regcomp(&regex, prefix, REG_EXTENDED))
720 die("Invalid search pattern: %s", prefix);
722 for (l = list; l; l = l->next) {
723 l->item->object.flags |= ONELINE_SEEN;
724 commit_list_insert(l->item, &backup);
726 while (list) {
727 char *p, *to_free = NULL;
728 struct commit *commit;
729 enum object_type type;
730 unsigned long size;
731 int matches;
733 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
734 if (!parse_object(commit->object.sha1))
735 continue;
736 if (commit->buffer)
737 p = commit->buffer;
738 else {
739 p = read_sha1_file(commit->object.sha1, &type, &size);
740 if (!p)
741 continue;
742 to_free = p;
745 p = strstr(p, "\n\n");
746 matches = p && !regexec(&regex, p + 2, 0, NULL, 0);
747 free(to_free);
749 if (matches) {
750 hashcpy(sha1, commit->object.sha1);
751 found = 1;
752 break;
755 regfree(&regex);
756 free_commit_list(list);
757 for (l = backup; l; l = l->next)
758 clear_commit_marks(l->item, ONELINE_SEEN);
759 free_commit_list(backup);
760 return found ? 0 : -1;
763 struct grab_nth_branch_switch_cbdata {
764 long cnt, alloc;
765 struct strbuf *buf;
768 static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
769 const char *email, unsigned long timestamp, int tz,
770 const char *message, void *cb_data)
772 struct grab_nth_branch_switch_cbdata *cb = cb_data;
773 const char *match = NULL, *target = NULL;
774 size_t len;
775 int nth;
777 if (!prefixcmp(message, "checkout: moving from ")) {
778 match = message + strlen("checkout: moving from ");
779 target = strstr(match, " to ");
782 if (!match || !target)
783 return 0;
785 len = target - match;
786 nth = cb->cnt++ % cb->alloc;
787 strbuf_reset(&cb->buf[nth]);
788 strbuf_add(&cb->buf[nth], match, len);
789 return 0;
793 * Parse @{-N} syntax, return the number of characters parsed
794 * if successful; otherwise signal an error with negative value.
796 static int interpret_nth_prior_checkout(const char *name, struct strbuf *buf)
798 long nth;
799 int i, retval;
800 struct grab_nth_branch_switch_cbdata cb;
801 const char *brace;
802 char *num_end;
804 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
805 return -1;
806 brace = strchr(name, '}');
807 if (!brace)
808 return -1;
809 nth = strtol(name+3, &num_end, 10);
810 if (num_end != brace)
811 return -1;
812 if (nth <= 0)
813 return -1;
814 cb.alloc = nth;
815 cb.buf = xmalloc(nth * sizeof(struct strbuf));
816 for (i = 0; i < nth; i++)
817 strbuf_init(&cb.buf[i], 20);
818 cb.cnt = 0;
819 retval = 0;
820 for_each_recent_reflog_ent("HEAD", grab_nth_branch_switch, 40960, &cb);
821 if (cb.cnt < nth) {
822 cb.cnt = 0;
823 for_each_reflog_ent("HEAD", grab_nth_branch_switch, &cb);
825 if (cb.cnt < nth)
826 goto release_return;
827 i = cb.cnt % nth;
828 strbuf_reset(buf);
829 strbuf_add(buf, cb.buf[i].buf, cb.buf[i].len);
830 retval = brace-name+1;
832 release_return:
833 for (i = 0; i < nth; i++)
834 strbuf_release(&cb.buf[i]);
835 free(cb.buf);
837 return retval;
840 int get_sha1_mb(const char *name, unsigned char *sha1)
842 struct commit *one, *two;
843 struct commit_list *mbs;
844 unsigned char sha1_tmp[20];
845 const char *dots;
846 int st;
848 dots = strstr(name, "...");
849 if (!dots)
850 return get_sha1(name, sha1);
851 if (dots == name)
852 st = get_sha1("HEAD", sha1_tmp);
853 else {
854 struct strbuf sb;
855 strbuf_init(&sb, dots - name);
856 strbuf_add(&sb, name, dots - name);
857 st = get_sha1(sb.buf, sha1_tmp);
858 strbuf_release(&sb);
860 if (st)
861 return st;
862 one = lookup_commit_reference_gently(sha1_tmp, 0);
863 if (!one)
864 return -1;
866 if (get_sha1(dots[3] ? (dots + 3) : "HEAD", sha1_tmp))
867 return -1;
868 two = lookup_commit_reference_gently(sha1_tmp, 0);
869 if (!two)
870 return -1;
871 mbs = get_merge_bases(one, two, 1);
872 if (!mbs || mbs->next)
873 st = -1;
874 else {
875 st = 0;
876 hashcpy(sha1, mbs->item->object.sha1);
878 free_commit_list(mbs);
879 return st;
883 * This reads short-hand syntax that not only evaluates to a commit
884 * object name, but also can act as if the end user spelled the name
885 * of the branch from the command line.
887 * - "@{-N}" finds the name of the Nth previous branch we were on, and
888 * places the name of the branch in the given buf and returns the
889 * number of characters parsed if successful.
891 * - "<branch>@{upstream}" finds the name of the other ref that
892 * <branch> is configured to merge with (missing <branch> defaults
893 * to the current branch), and places the name of the branch in the
894 * given buf and returns the number of characters parsed if
895 * successful.
897 * If the input is not of the accepted format, it returns a negative
898 * number to signal an error.
900 * If the input was ok but there are not N branch switches in the
901 * reflog, it returns 0.
903 int interpret_branch_name(const char *name, struct strbuf *buf)
905 char *cp;
906 struct branch *upstream;
907 int namelen = strlen(name);
908 int len = interpret_nth_prior_checkout(name, buf);
909 int tmp_len;
911 if (!len)
912 return len; /* syntax Ok, not enough switches */
913 if (0 < len && len == namelen)
914 return len; /* consumed all */
915 else if (0 < len) {
916 /* we have extra data, which might need further processing */
917 struct strbuf tmp = STRBUF_INIT;
918 int used = buf->len;
919 int ret;
921 strbuf_add(buf, name + len, namelen - len);
922 ret = interpret_branch_name(buf->buf, &tmp);
923 /* that data was not interpreted, remove our cruft */
924 if (ret < 0) {
925 strbuf_setlen(buf, used);
926 return len;
928 strbuf_reset(buf);
929 strbuf_addbuf(buf, &tmp);
930 strbuf_release(&tmp);
931 /* tweak for size of {-N} versus expanded ref name */
932 return ret - used + len;
935 cp = strchr(name, '@');
936 if (!cp)
937 return -1;
938 tmp_len = upstream_mark(cp, namelen - (cp - name));
939 if (!tmp_len)
940 return -1;
941 len = cp + tmp_len - name;
942 cp = xstrndup(name, cp - name);
943 upstream = branch_get(*cp ? cp : NULL);
944 if (!upstream
945 || !upstream->merge
946 || !upstream->merge[0]->dst)
947 return error("No upstream branch found for '%s'", cp);
948 free(cp);
949 cp = shorten_unambiguous_ref(upstream->merge[0]->dst, 0);
950 strbuf_reset(buf);
951 strbuf_addstr(buf, cp);
952 free(cp);
953 return len;
956 int strbuf_branchname(struct strbuf *sb, const char *name)
958 int len = strlen(name);
959 if (interpret_branch_name(name, sb) == len)
960 return 0;
961 strbuf_add(sb, name, len);
962 return len;
965 int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
967 strbuf_branchname(sb, name);
968 if (name[0] == '-')
969 return -1;
970 strbuf_splice(sb, 0, 0, "refs/heads/", 11);
971 return check_refname_format(sb->buf, 0);
975 * This is like "get_sha1_basic()", except it allows "sha1 expressions",
976 * notably "xyz^" for "parent of xyz"
978 int get_sha1(const char *name, unsigned char *sha1)
980 struct object_context unused;
981 return get_sha1_with_context(name, sha1, &unused);
984 /* Must be called only when object_name:filename doesn't exist. */
985 static void diagnose_invalid_sha1_path(const char *prefix,
986 const char *filename,
987 const unsigned char *tree_sha1,
988 const char *object_name)
990 struct stat st;
991 unsigned char sha1[20];
992 unsigned mode;
994 if (!prefix)
995 prefix = "";
997 if (!lstat(filename, &st))
998 die("Path '%s' exists on disk, but not in '%s'.",
999 filename, object_name);
1000 if (errno == ENOENT || errno == ENOTDIR) {
1001 char *fullname = xmalloc(strlen(filename)
1002 + strlen(prefix) + 1);
1003 strcpy(fullname, prefix);
1004 strcat(fullname, filename);
1006 if (!get_tree_entry(tree_sha1, fullname,
1007 sha1, &mode)) {
1008 die("Path '%s' exists, but not '%s'.\n"
1009 "Did you mean '%s:%s' aka '%s:./%s'?",
1010 fullname,
1011 filename,
1012 object_name,
1013 fullname,
1014 object_name,
1015 filename);
1017 die("Path '%s' does not exist in '%s'",
1018 filename, object_name);
1022 /* Must be called only when :stage:filename doesn't exist. */
1023 static void diagnose_invalid_index_path(int stage,
1024 const char *prefix,
1025 const char *filename)
1027 struct stat st;
1028 struct cache_entry *ce;
1029 int pos;
1030 unsigned namelen = strlen(filename);
1031 unsigned fullnamelen;
1032 char *fullname;
1034 if (!prefix)
1035 prefix = "";
1037 /* Wrong stage number? */
1038 pos = cache_name_pos(filename, namelen);
1039 if (pos < 0)
1040 pos = -pos - 1;
1041 if (pos < active_nr) {
1042 ce = active_cache[pos];
1043 if (ce_namelen(ce) == namelen &&
1044 !memcmp(ce->name, filename, namelen))
1045 die("Path '%s' is in the index, but not at stage %d.\n"
1046 "Did you mean ':%d:%s'?",
1047 filename, stage,
1048 ce_stage(ce), filename);
1051 /* Confusion between relative and absolute filenames? */
1052 fullnamelen = namelen + strlen(prefix);
1053 fullname = xmalloc(fullnamelen + 1);
1054 strcpy(fullname, prefix);
1055 strcat(fullname, filename);
1056 pos = cache_name_pos(fullname, fullnamelen);
1057 if (pos < 0)
1058 pos = -pos - 1;
1059 if (pos < active_nr) {
1060 ce = active_cache[pos];
1061 if (ce_namelen(ce) == fullnamelen &&
1062 !memcmp(ce->name, fullname, fullnamelen))
1063 die("Path '%s' is in the index, but not '%s'.\n"
1064 "Did you mean ':%d:%s' aka ':%d:./%s'?",
1065 fullname, filename,
1066 ce_stage(ce), fullname,
1067 ce_stage(ce), filename);
1070 if (!lstat(filename, &st))
1071 die("Path '%s' exists on disk, but not in the index.", filename);
1072 if (errno == ENOENT || errno == ENOTDIR)
1073 die("Path '%s' does not exist (neither on disk nor in the index).",
1074 filename);
1076 free(fullname);
1080 int get_sha1_with_mode_1(const char *name, unsigned char *sha1, unsigned *mode,
1081 int only_to_die, const char *prefix)
1083 struct object_context oc;
1084 int ret;
1085 ret = get_sha1_with_context_1(name, sha1, &oc, only_to_die, prefix);
1086 *mode = oc.mode;
1087 return ret;
1090 static char *resolve_relative_path(const char *rel)
1092 if (prefixcmp(rel, "./") && prefixcmp(rel, "../"))
1093 return NULL;
1095 if (!startup_info)
1096 die("BUG: startup_info struct is not initialized.");
1098 if (!is_inside_work_tree())
1099 die("relative path syntax can't be used outside working tree.");
1101 /* die() inside prefix_path() if resolved path is outside worktree */
1102 return prefix_path(startup_info->prefix,
1103 startup_info->prefix ? strlen(startup_info->prefix) : 0,
1104 rel);
1107 int get_sha1_with_context_1(const char *name, unsigned char *sha1,
1108 struct object_context *oc,
1109 int only_to_die, const char *prefix)
1111 int ret, bracket_depth;
1112 int namelen = strlen(name);
1113 const char *cp;
1115 memset(oc, 0, sizeof(*oc));
1116 oc->mode = S_IFINVALID;
1117 ret = get_sha1_1(name, namelen, sha1);
1118 if (!ret)
1119 return ret;
1120 /* sha1:path --> object name of path in ent sha1
1121 * :path -> object name of absolute path in index
1122 * :./path -> object name of path relative to cwd in index
1123 * :[0-3]:path -> object name of path in index at stage
1124 * :/foo -> recent commit matching foo
1126 if (name[0] == ':') {
1127 int stage = 0;
1128 struct cache_entry *ce;
1129 char *new_path = NULL;
1130 int pos;
1131 if (!only_to_die && namelen > 2 && name[1] == '/') {
1132 struct commit_list *list = NULL;
1133 for_each_ref(handle_one_ref, &list);
1134 return get_sha1_oneline(name + 2, sha1, list);
1136 if (namelen < 3 ||
1137 name[2] != ':' ||
1138 name[1] < '0' || '3' < name[1])
1139 cp = name + 1;
1140 else {
1141 stage = name[1] - '0';
1142 cp = name + 3;
1144 new_path = resolve_relative_path(cp);
1145 if (!new_path) {
1146 namelen = namelen - (cp - name);
1147 } else {
1148 cp = new_path;
1149 namelen = strlen(cp);
1152 strncpy(oc->path, cp,
1153 sizeof(oc->path));
1154 oc->path[sizeof(oc->path)-1] = '\0';
1156 if (!active_cache)
1157 read_cache();
1158 pos = cache_name_pos(cp, namelen);
1159 if (pos < 0)
1160 pos = -pos - 1;
1161 while (pos < active_nr) {
1162 ce = active_cache[pos];
1163 if (ce_namelen(ce) != namelen ||
1164 memcmp(ce->name, cp, namelen))
1165 break;
1166 if (ce_stage(ce) == stage) {
1167 hashcpy(sha1, ce->sha1);
1168 oc->mode = ce->ce_mode;
1169 free(new_path);
1170 return 0;
1172 pos++;
1174 if (only_to_die && name[1] && name[1] != '/')
1175 diagnose_invalid_index_path(stage, prefix, cp);
1176 free(new_path);
1177 return -1;
1179 for (cp = name, bracket_depth = 0; *cp; cp++) {
1180 if (*cp == '{')
1181 bracket_depth++;
1182 else if (bracket_depth && *cp == '}')
1183 bracket_depth--;
1184 else if (!bracket_depth && *cp == ':')
1185 break;
1187 if (*cp == ':') {
1188 unsigned char tree_sha1[20];
1189 char *object_name = NULL;
1190 if (only_to_die) {
1191 object_name = xmalloc(cp-name+1);
1192 strncpy(object_name, name, cp-name);
1193 object_name[cp-name] = '\0';
1195 if (!get_sha1_1(name, cp-name, tree_sha1)) {
1196 const char *filename = cp+1;
1197 char *new_filename = NULL;
1199 new_filename = resolve_relative_path(filename);
1200 if (new_filename)
1201 filename = new_filename;
1202 ret = get_tree_entry(tree_sha1, filename, sha1, &oc->mode);
1203 if (only_to_die) {
1204 diagnose_invalid_sha1_path(prefix, filename,
1205 tree_sha1, object_name);
1206 free(object_name);
1208 hashcpy(oc->tree, tree_sha1);
1209 strncpy(oc->path, filename,
1210 sizeof(oc->path));
1211 oc->path[sizeof(oc->path)-1] = '\0';
1213 free(new_filename);
1214 return ret;
1215 } else {
1216 if (only_to_die)
1217 die("Invalid object name '%s'.", object_name);
1220 return ret;