1 files changed, 23 insertions, 20 deletions

diff --git a/builtin-merge-base.c b/builtin-merge-base.c
index 3382b1382a..03fc1c2114 100644
--- a/builtin-merge-base.c
+++ b/builtin-merge-base.c
@@ -1,10 +1,13 @@
 #include "builtin.h"
 #include "cache.h"
 #include "commit.h"
+#include "parse-options.h"
 
-static int show_merge_base(struct commit *rev1, struct commit *rev2, int show_all)
+static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
 {
-	struct commit_list *result = get_merge_bases(rev1, rev2, 0);
+	struct commit_list *result;
+
+	result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1, 0);
 
 	if (!result)
 		return 1;
@@ -19,8 +22,10 @@ static int show_merge_base(struct commit *rev1, struct commit *rev2, int show_al
 	return 0;
 }
 
-static const char merge_base_usage[] =
-"git merge-base [--all] <commit-id> <commit-id>";
+static const char * const merge_base_usage[] = {
+	"git merge-base [--all] <commit-id> <commit-id>...",
+	NULL
+};
 
 static struct commit *get_commit_reference(const char *arg)
 {
@@ -38,23 +43,21 @@ static struct commit *get_commit_reference(const char *arg)
 
 int cmd_merge_base(int argc, const char **argv, const char *prefix)
 {
-	struct commit *rev1, *rev2;
+	struct commit **rev;
+	int rev_nr = 0;
 	int show_all = 0;
 
-	git_config(git_default_config, NULL);
+	struct option options[] = {
+		OPT_BOOLEAN('a', "all", &show_all, "outputs all common ancestors"),
+		OPT_END()
+	};
 
-	while (1 < argc && argv[1][0] == '-') {
-		const char *arg = argv[1];
-		if (!strcmp(arg, "-a") || !strcmp(arg, "--all"))
-			show_all = 1;
-		else
-			usage(merge_base_usage);
-		argc--; argv++;
-	}
-	if (argc != 3)
-		usage(merge_base_usage);
-	rev1 = get_commit_reference(argv[1]);
-	rev2 = get_commit_reference(argv[2]);
-
-	return show_merge_base(rev1, rev2, show_all);
+	git_config(git_default_config, NULL);
+	argc = parse_options(argc, argv, options, merge_base_usage, 0);
+	if (argc < 2)
+		usage_with_options(merge_base_usage, options);
+	rev = xmalloc(argc * sizeof(*rev));
+	while (argc-- > 0)
+		rev[rev_nr++] = get_commit_reference(*argv++);
+	return show_merge_base(rev, rev_nr, show_all);
 }