X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=receive-pack.c;h=ea2dbd4e3398ca90823dcd453cbb52c5dcea135c;hb=e70866f53a8d31cde6cfff6396ba0d1f64029afb;hp=78f75da5ca99bd5457fd4e0f6e3af2737afc335a;hpb=7bbf88c52b202d543310123e1bad9a44b2d6f028;p=git.git

diff --git a/receive-pack.c b/receive-pack.c
index 78f75da5c..ea2dbd4e3 100644
--- a/receive-pack.c
+++ b/receive-pack.c
@@ -2,6 +2,8 @@
 #include "refs.h"
 #include "pkt-line.h"
 #include "run-command.h"
+#include "commit.h"
+#include "object.h"
 
 static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
 
@@ -127,6 +129,21 @@ static int update(struct command *cmd)
 		return error("unpack should have generated %s, "
 			     "but I can't find it!", new_hex);
 	}
+	if (deny_non_fast_forwards && !is_null_sha1(old_sha1)) {
+		struct commit *old_commit, *new_commit;
+		struct commit_list *bases, *ent;
+
+		old_commit = (struct commit *)parse_object(old_sha1);
+		new_commit = (struct commit *)parse_object(new_sha1);
+		bases = get_merge_bases(old_commit, new_commit, 1);
+		for (ent = bases; ent; ent = ent->next)
+			if (!hashcmp(old_sha1, ent->item->object.sha1))
+				break;
+		free_commit_list(bases);
+		if (!ent)
+			return error("denying non-fast forward;"
+				     " you should pull first");
+	}
 	safe_create_leading_directories(lock_name);
 
 	newfd = open(lock_name, O_CREAT | O_EXCL | O_WRONLY, 0666);