1 files changed, 48 insertions, 20 deletions

diff --git a/builtin/am.c b/builtin/am.c
index 4f77e07b95..4e396c8321 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1343,7 +1343,7 @@ static int parse_mail(struct am_state *state, const char *mail)
 	strbuf_addstr(&msg, "\n\n");
 	if (strbuf_read_file(&msg, am_path(state, "msg"), 0) < 0)
 		die_errno(_("could not read '%s'"), am_path(state, "msg"));
-	stripspace(&msg, 0);
+	strbuf_stripspace(&msg, 0);
 
 	if (state->signoff)
 		am_signoff(&msg);
@@ -1590,16 +1590,44 @@ static int build_fake_ancestor(const struct am_state *state, const char *index_f
 }
 
 /**
+ * Do the three-way merge using fake ancestor, his tree constructed
+ * from the fake ancestor and the postimage of the patch, and our
+ * state.
+ */
+static int run_fallback_merge_recursive(const struct am_state *state,
+					unsigned char *orig_tree,
+					unsigned char *our_tree,
+					unsigned char *his_tree)
+{
+	struct child_process cp = CHILD_PROCESS_INIT;
+	int status;
+
+	cp.git_cmd = 1;
+
+	argv_array_pushf(&cp.env_array, "GITHEAD_%s=%.*s",
+			 sha1_to_hex(his_tree), linelen(state->msg), state->msg);
+	if (state->quiet)
+		argv_array_push(&cp.env_array, "GIT_MERGE_VERBOSITY=0");
+
+	argv_array_push(&cp.args, "merge-recursive");
+	argv_array_push(&cp.args, sha1_to_hex(orig_tree));
+	argv_array_push(&cp.args, "--");
+	argv_array_push(&cp.args, sha1_to_hex(our_tree));
+	argv_array_push(&cp.args, sha1_to_hex(his_tree));
+
+	status = run_command(&cp) ? (-1) : 0;
+	discard_cache();
+	read_cache();
+	return status;
+}
+
+/**
  * Attempt a threeway merge, using index_path as the temporary index.
  */
 static int fall_back_threeway(const struct am_state *state, const char *index_path)
 {
 	unsigned char orig_tree[GIT_SHA1_RAWSZ], his_tree[GIT_SHA1_RAWSZ],
 		      our_tree[GIT_SHA1_RAWSZ];
-	const unsigned char *bases[1] = {orig_tree};
-	struct merge_options o;
-	struct commit *result;
-	char *his_tree_name;
 
 	if (get_sha1("HEAD", our_tree) < 0)
 		hashcpy(our_tree, EMPTY_TREE_SHA1_BIN);
@@ -1651,22 +1679,11 @@ static int fall_back_threeway(const struct am_state *state, const char *index_pa
 	 * changes.
 	 */
 
-	init_merge_options(&o);
-
-	o.branch1 = "HEAD";
-	his_tree_name = xstrfmt("%.*s", linelen(state->msg), state->msg);
-	o.branch2 = his_tree_name;
-
-	if (state->quiet)
-		o.verbosity = 0;
-
-	if (merge_recursive_generic(&o, our_tree, his_tree, 1, bases, &result)) {
+	if (run_fallback_merge_recursive(state, orig_tree, our_tree, his_tree)) {
 		rerere(state->allow_rerere_autoupdate);
-		free(his_tree_name);
 		return error(_("Failed to merge in the changes."));
 	}
 
-	free(his_tree_name);
 	return 0;
 }
 
@@ -2208,6 +2225,17 @@ enum resume_mode {
 	RESUME_ABORT
 };
 
+static int git_am_config(const char *k, const char *v, void *cb)
+{
+	int status;
+
+	status = git_gpg_config(k, v, NULL);
+	if (status)
+		return status;
+
+	return git_default_config(k, v, NULL);
+}
+
 int cmd_am(int argc, const char **argv, const char *prefix)
 {
 	struct am_state state;
@@ -2218,8 +2246,8 @@ int cmd_am(int argc, const char **argv, const char *prefix)
 	int in_progress;
 
 	const char * const usage[] = {
-		N_("git am [options] [(<mbox>|<Maildir>)...]"),
-		N_("git am [options] (--continue | --skip | --abort)"),
+		N_("git am [<options>] [(<mbox>|<Maildir>)...]"),
+		N_("git am [<options>] (--continue | --skip | --abort)"),
 		NULL
 	};
 
@@ -2308,7 +2336,7 @@ int cmd_am(int argc, const char **argv, const char *prefix)
 		OPT_END()
 	};
 
-	git_config(git_default_config, NULL);
+	git_config(git_am_config, NULL);
 
 	am_state_init(&state, git_path("rebase-apply"));