+#include <stdlib.h>
#include "cache.h"
-#include "revision.h"
+#include "commit.h"
-/*
- * This is stupid. We could have much better heurstics, I bet.
- */
-static int better(struct revision *new, struct revision *old)
+static struct commit *process_list(struct commit_list **list_p, int this_mark,
+ int other_mark)
{
- return new->date > old->date;
+ struct commit *item = (*list_p)->item;
+
+ if (item->object.flags & other_mark) {
+ return item;
+ } else {
+ pop_most_recent_commit(list_p, this_mark);
+ }
+ return NULL;
}
-static struct revision *common_parent(struct revision *rev1, struct revision *rev2)
+static struct commit *common_ancestor(struct commit *rev1, struct commit *rev2)
{
- int i;
- struct revision *best = NULL;
-
- mark_reachable(rev1, 1);
- mark_reachable(rev2, 2);
- for (i = 0; i < nr_revs ;i++) {
- struct revision *rev = revs[i];
- if ((rev->flags & 3) != 3)
- continue;
- if (!best) {
- best = rev;
- continue;
+ struct commit_list *rev1list = NULL;
+ struct commit_list *rev2list = NULL;
+
+ commit_list_insert(rev1, &rev1list);
+ rev1->object.flags |= 0x1;
+ commit_list_insert(rev2, &rev2list);
+ rev2->object.flags |= 0x2;
+
+ parse_commit(rev1);
+ parse_commit(rev2);
+
+ while (rev1list || rev2list) {
+ struct commit *ret;
+ if (!rev1list) {
+ // process 2
+ ret = process_list(&rev2list, 0x2, 0x1);
+ } else if (!rev2list) {
+ // process 1
+ ret = process_list(&rev1list, 0x1, 0x2);
+ } else if (rev1list->item->date < rev2list->item->date) {
+ // process 2
+ ret = process_list(&rev2list, 0x2, 0x1);
+ } else {
+ // process 1
+ ret = process_list(&rev1list, 0x1, 0x2);
+ }
+ if (ret) {
+ free_commit_list(rev1list);
+ free_commit_list(rev2list);
+ return ret;
}
- if (better(rev, best))
- best = rev;
}
- return best;
+ return NULL;
}
int main(int argc, char **argv)
{
- unsigned char rev1[20], rev2[20];
- struct revision *common;
-
- if (argc != 3 || get_sha1_hex(argv[1], rev1) || get_sha1_hex(argv[2], rev2))
- usage("merge-base <commit1> <commit2>");
-
- /*
- * We will eventually want to include a revision cache file
- * that "rev-tree.c" has generated, since this is going to
- * otherwise be quite expensive for big trees..
- *
- * That's some time off, though, and in the meantime we know
- * that we have a solution to the eventual expense.
- */
- parse_commit(rev1);
- parse_commit(rev2);
+ struct commit *rev1, *rev2, *ret;
+ unsigned char rev1key[20], rev2key[20];
- common = common_parent(lookup_rev(rev1), lookup_rev(rev2));
- if (!common)
- die("no common parent found");
- printf("%s\n", sha1_to_hex(common->sha1));
+ if (argc != 3 ||
+ get_sha1(argv[1], rev1key) ||
+ get_sha1(argv[2], rev2key)) {
+ usage("git-merge-base <commit-id> <commit-id>");
+ }
+ rev1 = lookup_commit_reference(rev1key);
+ rev2 = lookup_commit_reference(rev2key);
+ ret = common_ancestor(rev1, rev2);
+ if (!ret)
+ return 1;
+ printf("%s\n", sha1_to_hex(ret->object.sha1));
return 0;
}