Merge branch 'master' into lj/refs

* master: (72 commits)
  runstatus: do not recurse into subdirectories if not needed
  grep: fix --fixed-strings combined with expression.
  grep: free expressions and patterns when done.
  Corrected copy-and-paste thinko in ignore executable bit test case.
  An illustration of rev-list --parents --pretty=raw
  Allow git-checkout when on a non-existant branch.
  gitweb: Decode long title for link tooltips
  git-svn: Fix fetch --no-ignore-externals with GIT_SVN_NO_LIB=1
  Ignore executable bit when adding files if filemode=0.
  Remove empty ref directories that prevent creating a ref.
  Use const for interpolate arguments
  git-archive: update documentation
  Deprecate merge-recursive.py
  gitweb: fix over-eager application of esc_html().
  Allow '(no author)' in git-svn's authors file.
  Allow 'svn fetch' on '(no date)' revisions in Subversion.
  git-repack: allow git-repack to run in subdirectory
  Remove upload-tar and make git-tar-tree a thin wrapper to git-archive
  git-tar-tree: Move code for git-archive --format=tar to archive-tar.c
  git-tar-tree: Remove duplicate git_config() call
  ...

1 files changed, 17 insertions, 0 deletions

diff --git a/receive-pack.c b/receive-pack.c
index c8aacbbdd3..1fcf3a9112 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>";
 
@@ -94,6 +96,21 @@ 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");
+	}
 	if (run_update_hook(name, old_hex, new_hex)) {
 		cmd->error_string = "hook declined";
 		return error("hook declined to update %s", name);