q3map2: fix segfault when missing bspfile arg on light stage

diff --git a/tools/quake3/q3map2/light.c b/tools/quake3/q3map2/light.c
index e43906e0aadfc87f34a0636f5424a66d3c65b4a3..79098148cbe5c503b33cf27497ed6c33fe486ec8 100644 (file)
--- a/tools/quake3/q3map2/light.c
+++ b/tools/quake3/q3map2/light.c
@@ -2981,6 +2981,11 @@ int LightMain( int argc, char **argv ){
                Sys_Printf( "Restricted lightmap searching enabled - block size adjusted to %d\n", lightmapSearchBlockSize );
        }
 
+       /* arg checking */
+       if ( i != ( argc - 1 ) ) {
+               Error( "usage: q3map -light [options] <bspfile>" );
+       }
+
        strcpy( source, ExpandArg( argv[ i ] ) );
        StripExtension( source );
        DefaultExtension( source, ".map" );