engine: client: let loading custom menu dll with -menulib command line switch

engine/common/common.h

@@ -358,6 +358,7 @@ typedef struct host_parm_s
 	int      window_center_y;
 	string   gamedll;
 	string   clientlib;
+	string   menulib;
 } host_parm_t;
 
 extern host_parm_t	host;

engine/common/filesystem_engine.c

@@ -328,6 +328,9 @@ void FS_Init( const char *basedir )
 
 	if( !Sys_GetParmFromCmdLine( "-clientlib", host.clientlib ))
 		host.clientlib[0] = 0;
+
+	if( !Sys_GetParmFromCmdLine( "-menulib", host.menulib ))
+		host.menulib[0] = 0;
 }
 
 /*

engine/common/host.c

@@ -177,6 +177,7 @@ static void Sys_PrintUsage( const char *exename )
 	O("-dll <path>        ", "override server DLL path")
 #if !XASH_DEDICATED
 	O("-clientlib <path>  ", "override client DLL path")
+	O("-menulib <path>    ", "override menu DLL path")
 	O("-console           ", "run engine with console enabled")
 	O("-toconsole         ", "run engine witn console open")
 	O("-oldfont           ", "enable unused Quake font in Half-Life")

engine/common/lib_common.c

@@ -228,7 +228,14 @@ void COM_GetCommonLibraryPath( ECommonLibraryType eLibType, char *out, size_t si
 	switch( eLibType )
 	{
 	case LIBRARY_GAMEUI:
-		COM_GenerateClientLibraryPath( "menu", out, size );
+		if( COM_CheckStringEmpty( host.menulib ))
+		{
+			Q_strncpy( out, host.menulib, size );
+		}
+		else
+		{
+			COM_GenerateClientLibraryPath( "menu", out, size );
+		}
 		break;
 	case LIBRARY_CLIENT:
 		if( COM_CheckStringEmpty( host.clientlib ))