Merge branch 'jc/merge-base' (early part)

This contains an evil merge to fast-import, in order to
resolve in_merge_bases() update.

Makefile

@@ -291,6 +291,7 @@ BUILTIN_OBJS = \
 	builtin-ls-tree.o \
 	builtin-mailinfo.o \
 	builtin-mailsplit.o \
+	builtin-merge-base.o \
 	builtin-merge-file.o \
 	builtin-mv.o \
 	builtin-name-rev.o \

builtin-branch.c

@@ -134,7 +134,7 @@ static int delete_branches(int argc, const char **argv, int force, int kinds)
 		 */
 
 		if (!force &&
-		    !in_merge_bases(rev, head_rev)) {
+		    !in_merge_bases(rev, &head_rev, 1)) {
 			error("The branch '%s' is not a strict subset of "
 				"your current HEAD.\n"
 				"If you are sure you want to delete it, "

builtin-merge-base.c

@@ -1,9 +1,7 @@
 #include "cache.h"
 #include "commit.h"
 
-static int show_all;
-
-static int merge_base(struct commit *rev1, struct commit *rev2)
+static int show_merge_base(struct commit *rev1, struct commit *rev2, int show_all)
 {
 	struct commit_list *result = get_merge_bases(rev1, rev2, 0);
 
@@ -23,16 +21,16 @@ static int merge_base(struct commit *rev1, struct commit *rev2)
 static const char merge_base_usage[] =
 "git-merge-base [--all] <commit-id> <commit-id>";
 
-int main(int argc, char **argv)
+int cmd_merge_base(int argc, const char **argv, const char *prefix)
 {
 	struct commit *rev1, *rev2;
 	unsigned char rev1key[20], rev2key[20];
+	int show_all = 0;
 
-	setup_git_directory();
 	git_config(git_default_config);
 
 	while (1 < argc && argv[1][0] == '-') {
-		char *arg = argv[1];
+		const char *arg = argv[1];
 		if (!strcmp(arg, "-a") || !strcmp(arg, "--all"))
 			show_all = 1;
 		else
@@ -49,5 +47,5 @@ int main(int argc, char **argv)
 	rev2 = lookup_commit_reference(rev2key);
 	if (!rev1 || !rev2)
 		return 1;
-	return merge_base(rev1, rev2);
+	return show_merge_base(rev1, rev2, show_all);
 }

builtin-reflog.c

@@ -215,8 +215,8 @@ static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 			old = lookup_commit_reference_gently(osha1, 1);
 		if (!new && !is_null_sha1(nsha1))
 			new = lookup_commit_reference_gently(nsha1, 1);
-		if ((old && !in_merge_bases(old, cb->ref_commit)) ||
-		    (new && !in_merge_bases(new, cb->ref_commit)))
+		if ((old && !in_merge_bases(old, &cb->ref_commit, 1)) ||
+		    (new && !in_merge_bases(new, &cb->ref_commit, 1)))
 			goto prune;
 	}
 

builtin.h

@@ -44,6 +44,7 @@ extern int cmd_ls_files(int argc, const char **argv, const char *prefix);
 extern int cmd_ls_tree(int argc, const char **argv, const char *prefix);
 extern int cmd_mailinfo(int argc, const char **argv, const char *prefix);
 extern int cmd_mailsplit(int argc, const char **argv, const char *prefix);
+extern int cmd_merge_base(int argc, const char **argv, const char *prefix);
 extern int cmd_merge_file(int argc, const char **argv, const char *prefix);
 extern int cmd_mv(int argc, const char **argv, const char *prefix);
 extern int cmd_name_rev(int argc, const char **argv, const char *prefix);

commit.c

@@ -1187,14 +1187,17 @@ struct commit_list *get_merge_bases(struct commit *one,
 	return result;
 }
 
-int in_merge_bases(struct commit *rev1, struct commit *rev2)
+int in_merge_bases(struct commit *commit, struct commit **reference, int num)
 {
 	struct commit_list *bases, *b;
 	int ret = 0;
 
-	bases = get_merge_bases(rev1, rev2, 1);
+	if (num == 1)
+		bases = get_merge_bases(commit, *reference, 1);
+	else
+		die("not yet");
 	for (b = bases; b; b = b->next) {
-		if (!hashcmp(rev1->object.sha1, b->item->object.sha1)) {
+		if (!hashcmp(commit->object.sha1, b->item->object.sha1)) {
 			ret = 1;
 			break;
 		}

commit.h

@@ -114,5 +114,5 @@ extern int is_repository_shallow(void);
 extern struct commit_list *get_shallow_commits(struct object_array *heads,
 		int depth, int shallow_flag, int not_shallow_flag);
 
-int in_merge_bases(struct commit *rev1, struct commit *rev2);
+int in_merge_bases(struct commit *, struct commit **, int);
 #endif /* COMMIT_H */

fast-import.c

@@ -1308,7 +1308,7 @@ static int update_branch(struct branch *b)
 			return error("Branch %s is missing commits.", b->name);
 		}
 
-		if (!in_merge_bases(old_cmit, new_cmit)) {
+		if (!in_merge_bases(old_cmit, &new_cmit, 1)) {
 			unlock_ref(lock);
 			warn("Not updating %s"
 				" (new tip %s does not contain %s)",

git.c

@@ -256,6 +256,7 @@ static void handle_internal_command(int argc, const char **argv, char **envp)
 		{ "ls-tree", cmd_ls_tree, RUN_SETUP },
 		{ "mailinfo", cmd_mailinfo },
 		{ "mailsplit", cmd_mailsplit },
+		{ "merge-base", cmd_merge_base, RUN_SETUP },
 		{ "merge-file", cmd_merge_file },
 		{ "mv", cmd_mv, RUN_SETUP | NOT_BARE },
 		{ "name-rev", cmd_name_rev, RUN_SETUP },