transport-helper: check status code of finish_command

Previously the status code of all helpers were ignored, allowing
errors that occur to go unnoticed if the error text output by the
helper is not noticed.

Signed-off-by: Sverre Rabbelier <srabbelier@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

transport-helper.c

@@ -209,6 +209,7 @@ static int disconnect_helper(struct transport *transport)
 {
 	struct helper_data *data = transport->data;
 	struct strbuf buf = STRBUF_INIT;
+	int res = 0;
 
 	if (data->helper) {
 		if (debug)
@@ -220,13 +221,13 @@ static int disconnect_helper(struct transport *transport)
 		close(data->helper->in);
 		close(data->helper->out);
 		fclose(data->out);
-		finish_command(data->helper);
+		res = finish_command(data->helper);
 		free((char *)data->helper->argv[0]);
 		free(data->helper->argv);
 		free(data->helper);
 		data->helper = NULL;
 	}
-	return 0;
+	return res;
 }
 
 static const char *unsupported_options[] = {
@@ -304,12 +305,13 @@ static void standard_options(struct transport *t)
 
 static int release_helper(struct transport *transport)
 {
+	int res = 0;
 	struct helper_data *data = transport->data;
 	free_refspec(data->refspec_nr, data->refspecs);
 	data->refspecs = NULL;
-	disconnect_helper(transport);
+	res = disconnect_helper(transport);
 	free(transport->data);
-	return 0;
+	return res;
 }
 
 static int fetch_with_fetch(struct transport *transport,
@@ -415,8 +417,11 @@ static int fetch_with_import(struct transport *transport,
 		sendline(data, &buf);
 		strbuf_reset(&buf);
 	}
-	disconnect_helper(transport);
+	if (disconnect_helper(transport))
-	finish_command(&fastimport);
+		die("Error while disconnecting helper");
+	if (finish_command(&fastimport))
+		die("Error while running fast-import");
+
 	free(fastimport.argv);
 	fastimport.argv = NULL;
 
@@ -760,8 +765,10 @@ static int push_refs_with_export(struct transport *transport,
 		die("Couldn't run fast-export");
 
 	data->no_disconnect_req = 1;
-	finish_command(&exporter);
+	if (finish_command(&exporter))
-	disconnect_helper(transport);
+		die("Error while running fast-export");
+	if (disconnect_helper(transport))
+		die("Error while disconnecting helper");
 	return 0;
 }