[PATH wayland] allow to set server socket dir on a different directory than XDG_RUNTIME_DIR

[Bettio, Davide]

commit 68beb2b60f851c74b982b0a23da4bb1ce375efcf
Author: Davide Bettio <davide.bettio at ispirata.com>
Date:   Wed Feb 4 13:46:19 2015 +0100

     Allow to explicitly set wayland server socket dir using 
WAYLAND_SERVER_SOCKET_DIR

diff --git a/src/wayland-server.c b/src/wayland-server.c
index 674aeca..7eaba9e 100644
--- a/src/wayland-server.c
+++ b/src/wayland-server.c
@@ -1080,9 +1080,12 @@ wl_socket_init_for_display_name(struct wl_socket 
*s, const char *name)
  	int name_size;
  	const char *runtime_dir;

-	runtime_dir = getenv("XDG_RUNTIME_DIR");
+	runtime_dir = getenv("WAYLAND_SERVER_SOCKET_DIR");
  	if (!runtime_dir) {
-		wl_log("error: XDG_RUNTIME_DIR not set in the environment\n");
+		runtime_dir = getenv("XDG_RUNTIME_DIR");
+	}
+	if (!runtime_dir) {
+		wl_log("error: XDG_RUNTIME_DIR or WAYLAND_SERVER_SOCKET_DIR not set 
in the environment\n");

  		/* to prevent programs reporting
  		 * "failed to add socket: Success" */