X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=merge-base.c;h=009caf804b43fdd644ff08991d55d0e417fd34d8;hb=5c5b2ea9ab95f71ac155f12d75d1432b5c93c2bb;hp=286bf0e8d1522ac4cf01f75343da40ddff6bf6e8;hpb=1301c6eb412e7c5511b952a12e42c70ad56f028b;p=git.git diff --git a/merge-base.c b/merge-base.c index 286bf0e8d..009caf804 100644 --- a/merge-base.c +++ b/merge-base.c @@ -2,144 +2,22 @@ #include "cache.h" #include "commit.h" -#define PARENT1 1 -#define PARENT2 2 -#define UNINTERESTING 4 - -static struct commit *interesting(struct commit_list *list) -{ - while (list) { - struct commit *commit = list->item; - list = list->next; - if (commit->object.flags & UNINTERESTING) - continue; - return commit; - } - return NULL; -} - -/* - * A pathological example of how this thing works. - * - * Suppose we had this commit graph, where chronologically - * the timestamp on the commit are A <= B <= C <= D <= E <= F - * and we are trying to figure out the merge base for E and F - * commits. - * - * F - * / \ - * E A D - * \ / / - * B / - * \ / - * C - * - * First we push E and F to list to be processed. E gets bit 1 - * and F gets bit 2. The list becomes: - * - * list=F(2) E(1), result=empty - * - * Then we pop F, the newest commit, from the list. Its flag is 2. - * We scan its parents, mark them reachable from the side that F is - * reachable from, and push them to the list: - * - * list=E(1) D(2) A(2), result=empty - * - * Next pop E and do the same. - * - * list=D(2) B(1) A(2), result=empty - * - * Next pop D and do the same. - * - * list=C(2) B(1) A(2), result=empty - * - * Next pop C and do the same. - * - * list=B(1) A(2), result=empty - * - * Now it is B's turn. We mark its parent, C, reachable from B's side, - * and push it to the list: - * - * list=C(3) A(2), result=empty - * - * Now pop C and notice it has flags==3. It is placed on the result list, - * and the list now contains: - * - * list=A(2), result=C(3) - * - * We pop A and do the same. - * - * list=B(3), result=C(3) - * - * Next, we pop B and something very interesting happens. It has flags==3 - * so it is also placed on the result list, and its parents are marked - * uninteresting, retroactively, and placed back on the list: - * - * list=C(7), result=C(7) B(3) - * - * Now, list does not have any interesting commit. So we find the newest - * commit from the result list that is not marked uninteresting. Which is - * commit B. - */ - -static int show_all = 0; +static int show_all; static int merge_base(struct commit *rev1, struct commit *rev2) { - struct commit_list *list = NULL; - struct commit_list *result = NULL; - - if (rev1 == rev2) { - printf("%s\n", sha1_to_hex(rev1->object.sha1)); - return 0; - } - - parse_commit(rev1); - parse_commit(rev2); - - rev1->object.flags |= 1; - rev2->object.flags |= 2; - insert_by_date(rev1, &list); - insert_by_date(rev2, &list); - - while (interesting(list)) { - struct commit *commit = list->item; - struct commit_list *tmp = list, *parents; - int flags = commit->object.flags & 7; - - list = list->next; - free(tmp); - if (flags == 3) { - insert_by_date(commit, &result); - - /* Mark parents of a found merge uninteresting */ - flags |= UNINTERESTING; - } - parents = commit->parents; - while (parents) { - struct commit *p = parents->item; - parents = parents->next; - if ((p->object.flags & flags) == flags) - continue; - parse_commit(p); - p->object.flags |= flags; - insert_by_date(p, &list); - } - } + struct commit_list *result = get_merge_bases(rev1, rev2, 0); if (!result) return 1; while (result) { - struct commit *commit = result->item; - result = result->next; - if (commit->object.flags & UNINTERESTING) - continue; - printf("%s\n", sha1_to_hex(commit->object.sha1)); + printf("%s\n", sha1_to_hex(result->item->object.sha1)); if (!show_all) return 0; - commit->object.flags |= UNINTERESTING; + result = result->next; } + return 0; } @@ -151,6 +29,9 @@ int main(int argc, char **argv) struct commit *rev1, *rev2; unsigned char rev1key[20], rev2key[20]; + setup_git_directory(); + git_config(git_default_config); + while (1 < argc && argv[1][0] == '-') { char *arg = argv[1]; if (!strcmp(arg, "-a") || !strcmp(arg, "--all")) @@ -159,10 +40,12 @@ int main(int argc, char **argv) usage(merge_base_usage); argc--; argv++; } - if (argc != 3 || - get_sha1(argv[1], rev1key) || - get_sha1(argv[2], rev2key)) + if (argc != 3) usage(merge_base_usage); + if (get_sha1(argv[1], rev1key)) + die("Not a valid object name %s", argv[1]); + if (get_sha1(argv[2], rev2key)) + die("Not a valid object name %s", argv[2]); rev1 = lookup_commit_reference(rev1key); rev2 = lookup_commit_reference(rev2key); if (!rev1 || !rev2)