Refactor run_command error handling in receive-pack

I'm pulling the error handling used to decode the result of
run_command up into a new function so that I can reuse it.
No changes, just a simple code movement.
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

receive-pack.c

@@ -71,6 +71,29 @@ static const char update_hook[] = "hooks/update";
 static const char pre_receive_hook[] = "hooks/pre-receive";
 static const char post_receive_hook[] = "hooks/post-receive";
 
+static int hook_status(int code, const char *hook_name)
+{
+	switch (code) {
+	case 0:
+		return 0;
+	case -ERR_RUN_COMMAND_FORK:
+		return error("hook fork failed");
+	case -ERR_RUN_COMMAND_EXEC:
+		return error("hook execute failed");
+	case -ERR_RUN_COMMAND_WAITPID:
+		return error("waitpid failed");
+	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
+		return error("waitpid is confused");
+	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
+		return error("%s died of signal", hook_name);
+	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
+		return error("%s died strangely", hook_name);
+	default:
+		error("%s exited with error code %d", hook_name, -code);
+		return -code;
+	}
+}
+
 static int run_hook(const char *hook_name,
 	struct command *first_cmd,
 	int single)
@@ -108,25 +131,7 @@ static int run_hook(const char *hook_name,
 		free((char*)argv[argc]);
 	free(argv);
 
-	switch (code) {
-	case 0:
-		return 0;
-	case -ERR_RUN_COMMAND_FORK:
-		return error("hook fork failed");
-	case -ERR_RUN_COMMAND_EXEC:
-		return error("hook execute failed");
-	case -ERR_RUN_COMMAND_WAITPID:
-		return error("waitpid failed");
-	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
-		return error("waitpid is confused");
-	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
-		return error("%s died of signal", hook_name);
-	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
-		return error("%s died strangely", hook_name);
-	default:
-		error("%s exited with error code %d", hook_name, -code);
-		return -code;
-	}
+	return hook_status(code, hook_name);
 }
 
 static const char *update(struct command *cmd)