X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=merge-base.c;h=591956666d06603d145ac9a5d2102185289e4c2c;hb=24db845c40b09c55eb810c01e7fda2f4505d35ba;hp=0b99598f305593de5d48e6cbafcbdea359349c45;hpb=b5039db6d25ae25f1cb2db541ed13602784fafc3;p=git.git

diff --git a/merge-base.c b/merge-base.c
index 0b99598f..59195666 100644
--- a/merge-base.c
+++ b/merge-base.c
@@ -2,74 +2,50 @@
 #include "cache.h"
 #include "commit.h"
 
-static struct commit *process_list(struct commit_list **list_p, int this_mark,
-				   int other_mark)
+static struct commit *common_ancestor(struct commit *rev1, struct commit *rev2)
 {
-	struct commit_list *parent, *temp;
-	struct commit_list *posn = *list_p;
-	*list_p = NULL;
-	while (posn) {
-		parse_commit(posn->item);
-		if (posn->item->object.flags & this_mark) {
-			/*
-			  printf("%d already seen %s %x\n",
-			  this_mark
-			  sha1_to_hex(posn->parent->sha1),
-			  posn->parent->flags);
-			*/
-			/* do nothing; this indicates that this side
-			 * split and reformed, and we only need to
-			 * mark it once.
-			 */
-		} else if (posn->item->object.flags & other_mark) {
-			return posn->item;
-		} else {
-			/*
-			  printf("%d based on %s\n",
-			  this_mark,
-			  sha1_to_hex(posn->parent->sha1));
-			*/
-			posn->item->object.flags |= this_mark;
-			
-			parent = posn->item->parents;
-			while (parent) {
-				temp = malloc(sizeof(struct commit_list));
-				temp->next = *list_p;
-				temp->item = parent->item;
-				*list_p = temp;
-				parent = parent->next;
-			}
-		}
-		posn = posn->next;
-	}
-	return NULL;
-}
+	struct commit_list *list = NULL;
+	struct commit_list *result = NULL;
 
-struct commit *common_ancestor(struct commit *rev1, struct commit *rev2)
-{
-	struct commit_list *rev1list = malloc(sizeof(struct commit_list));
-	struct commit_list *rev2list = malloc(sizeof(struct commit_list));
+	if (rev1 == rev2)
+		return rev1;
 
-	rev1list->item = rev1;
-	rev1list->next = NULL;
+	parse_commit(rev1);
+	parse_commit(rev2);
 
-	rev2list->item = rev2;
-	rev2list->next = NULL;
+	rev1->object.flags |= 1;
+	rev2->object.flags |= 2;
+	insert_by_date(rev1, &list);
+	insert_by_date(rev2, &list);
 
-	while (rev1list || rev2list) {
-		struct commit *ret;
-		ret = process_list(&rev1list, 0x1, 0x2);
-		if (ret) {
-			/* XXXX free lists */
-			return ret;
+	while (list) {
+		struct commit *commit = list->item;
+		struct commit_list *tmp = list, *parents;
+		int flags = commit->object.flags & 3;
+
+		list = list->next;
+		free(tmp);
+		switch (flags) {
+		case 3:
+			insert_by_date(commit, &result);
+			continue;
+		case 0:
+			die("git-merge-base: commit without either parent?");
 		}
-		ret = process_list(&rev2list, 0x2, 0x1);
-		if (ret) {
-			/* XXXX free lists */
-			return ret;
+		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);
 		}
 	}
-	return NULL;
+	if (!result)
+		return NULL;
+	return result->item;
 }
 
 int main(int argc, char **argv)
@@ -78,18 +54,17 @@ int main(int argc, char **argv)
 	unsigned char rev1key[20], rev2key[20];
 
 	if (argc != 3 ||
-	    get_sha1_hex(argv[1], rev1key) ||
-	    get_sha1_hex(argv[2], rev2key)) {
-		usage("merge-base <commit-id> <commit-id>");
+	    get_sha1(argv[1], rev1key) ||
+	    get_sha1(argv[2], rev2key)) {
+		usage("git-merge-base <commit-id> <commit-id>");
 	}
-	rev1 = lookup_commit(rev1key);
-	rev2 = lookup_commit(rev2key);
+	rev1 = lookup_commit_reference(rev1key);
+	rev2 = lookup_commit_reference(rev2key);
+	if (!rev1 || !rev2)
+		return 1;
 	ret = common_ancestor(rev1, rev2);
-	if (ret) {
-		printf("%s\n", sha1_to_hex(ret->object.sha1));
-		return 0;
-	} else {
+	if (!ret)
 		return 1;
-	}
-	
+	printf("%s\n", sha1_to_hex(ret->object.sha1));
+	return 0;
 }