Date: Sun, 18 Apr 2004 16:09:53 -0400 (EDT) From: David MacCormack Subject: [SDL] Linux joystick patch I recently got myself a PS2 -> USB converter (a super joybox 5). It accepts 4 PSX/PS2 controllers. It's implemented as a HID, which is nice because it doesn't require its own driver, but the problem is that it's implemented as a *single* HID -- that is, it shows up as a single joystick with 19 axes, 4 hats, and 48 buttons. This poses a problem for a number of apps which use SDL (stella, fce ultra, zsnes, to name a few) and see only a single (physical) joystick even though there are really 4 (logical) joysticks. There are a number of these types of devices on the market, and I've seen others post messages (in the zsnes forum, for example) with the same problem, so I came up with what I think is a pretty generic solution. I patched src/joystick/linux/SDL_sysjoystic.c to include support for logical joysticks; basically, it's a static array and supporting functions that map a single physical joystick to multiple logical joysticks. The attached patch has the new code. It's wrapped inside #ifndef statements so that you can get the old behavior if you want.

#include <stdio.h>
#include "SDL_main.h"
#include "SDL_types.h"

int main(int argc, char *argv[])
{
	int error = 0;
	int verbose = 1;

	if ( argv[1] && (strcmp(argv[1], "-q") == 0) )
		verbose = 0;

	if ( sizeof(Uint8) != 1 ) {
		if ( verbose )
			printf("sizeof(Uint8) != 1, instead = %d\n",
								sizeof(Uint8));
		++error;
	}
	if ( sizeof(Uint16) != 2 ) {
		if ( verbose )
			printf("sizeof(Uint16) != 2, instead = %d\n",
								sizeof(Uint16));
		++error;
	}
	if ( sizeof(Uint32) != 4 ) {
		if ( verbose )
			printf("sizeof(Uint32) != 4, instead = %d\n",
								sizeof(Uint32));
		++error;
	}
#ifdef SDL_HAS_64BIT_TYPE
	if ( sizeof(Uint64) != 8 ) {
		if ( verbose )
			printf("sizeof(Uint64) != 8, instead = %d\n",
								sizeof(Uint64));
		++error;
	}
#else
	if ( verbose ) {
		printf("WARNING: No 64-bit datatype on this platform\n");
	}
#endif
	if ( verbose && ! error )
		printf("All data types are the expected size.\n");

	return( error ? 1 : 0 );
}