view src/audio/dmedia/SDL_irixaudio.c @ 937:1e6366bde299

Date: Tue, 27 Jul 2004 17:14:00 +0200 From: "Eckhard Stolberg" Subject: Controller names in SDL for Windows I'm working on an Atari 2600 emulator for different systems that uses the SDL. Some time ago someone created an adaptor that lets you use your old Atari controllers with your computer through the USB port. Some of the Atari controllers require special handling by the emulator, so it would be nice, if it would be possible to detect if any of the controllers connected to the computer is this adaptor. SDL would allow that with the SDL_JoystickName function, but unfortunately it doesn't work properly on Windows. On Linux and MacOSX this function returns the name of the controller, but on Windows you'll only get the name of the joystick driver. Most joysticks nowadays use the generic Microsoft driver, so they all return the same name. In an old MSDN article (http://msdn.microsoft.com/archive/default.asp?url=/archive/en-us/dnarinput/html/msdn_extdirect.asp) Microsoft describes how to read out the OEM controller names from the registry. I have implemented this for the SDL controller handler on Windows, and now reading the joystick name works properly there too.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 21 Aug 2004 03:45:58 +0000 (2004-08-21)
parents 6e6248801043
children c9b51268668f
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997, 1998  Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga
    5635-34 Springhouse Dr.
    Pleasanton, CA 94588 (USA)
    slouken@libsdl.org
*/

#ifdef SAVE_RCSID
static char rcsid =
 "@(#) $Id$";
#endif

/* Allow access to a raw mixing buffer (For IRIX 6.5 and higher) */
/* patch for IRIX 5 by Georg Schwarz 18/07/2004 */

#include <stdlib.h>

#include "SDL_endian.h"
#include "SDL_timer.h"
#include "SDL_audio.h"
#include "SDL_audiomem.h"
#include "SDL_audio_c.h"
#include "SDL_irixaudio.h"


#ifndef AL_RESOURCE /* as a test whether we use the old IRIX audio libraries */
#define OLD_IRIX_AUDIO
#define alClosePort(x) ALcloseport(x)
#define alFreeConfig(x) ALfreeconfig(x)
#define alGetFillable(x) ALgetfillable(x)
#define alNewConfig() ALnewconfig()
#define alOpenPort(x,y,z) ALopenport(x,y,z)
#define alSetChannels(x,y) ALsetchannels(x,y)
#define alSetQueueSize(x,y) ALsetqueuesize(x,y)
#define alSetSampFmt(x,y) ALsetsampfmt(x,y)
#define alSetWidth(x,y) ALsetwidth(x,y)
#endif

/* Audio driver functions */
static int AL_OpenAudio(_THIS, SDL_AudioSpec *spec);
static void AL_WaitAudio(_THIS);
static void AL_PlayAudio(_THIS);
static Uint8 *AL_GetAudioBuf(_THIS);
static void AL_CloseAudio(_THIS);

/* Audio driver bootstrap functions */

static int Audio_Available(void)
{
	return 1;
}

static void Audio_DeleteDevice(SDL_AudioDevice *device)
{
	free(device->hidden);
	free(device);
}

static SDL_AudioDevice *Audio_CreateDevice(int devindex)
{
	SDL_AudioDevice *this;

	/* Initialize all variables that we clean on shutdown */
	this = (SDL_AudioDevice *)malloc(sizeof(SDL_AudioDevice));
	if ( this ) {
		memset(this, 0, (sizeof *this));
		this->hidden = (struct SDL_PrivateAudioData *)
				malloc((sizeof *this->hidden));
	}
	if ( (this == NULL) || (this->hidden == NULL) ) {
		SDL_OutOfMemory();
		if ( this ) {
			free(this);
		}
		return(0);
	}
	memset(this->hidden, 0, (sizeof *this->hidden));

	/* Set the function pointers */
	this->OpenAudio = AL_OpenAudio;
	this->WaitAudio = AL_WaitAudio;
	this->PlayAudio = AL_PlayAudio;
	this->GetAudioBuf = AL_GetAudioBuf;
	this->CloseAudio = AL_CloseAudio;

	this->free = Audio_DeleteDevice;

	return this;
}

AudioBootStrap DMEDIA_bootstrap = {
	"AL", "IRIX DMedia audio",
	Audio_Available, Audio_CreateDevice
};


void static AL_WaitAudio(_THIS)
{
	Sint32 timeleft;

	timeleft = this->spec.samples - alGetFillable(audio_port);
	if ( timeleft > 0 ) {
		timeleft /= (this->spec.freq/1000);
		SDL_Delay((Uint32)timeleft);
	}
}

static void AL_PlayAudio(_THIS)
{
	/* Write the audio data out */
	if ( alWriteFrames(audio_port, mixbuf, this->spec.samples) < 0 ) {
		/* Assume fatal error, for now */
		this->enabled = 0;
	}
}

static Uint8 *AL_GetAudioBuf(_THIS)
{
	return(mixbuf);
}

static void AL_CloseAudio(_THIS)
{
	if ( mixbuf != NULL ) {
		SDL_FreeAudioMem(mixbuf);
		mixbuf = NULL;
	}
	if ( audio_port != NULL ) {
		alClosePort(audio_port);
		audio_port = NULL;
	}
}

static int AL_OpenAudio(_THIS, SDL_AudioSpec *spec)
{
	ALconfig audio_config;
#ifdef OLD_IRIX_AUDIO
	long audio_param[2];
#else
	ALpv audio_param;
#endif
	int width;

	/* Determine the audio parameters from the AudioSpec */
	switch ( spec->format & 0xFF ) {

		case 8: { /* Signed 8 bit audio data */
			spec->format = AUDIO_S8;
			width = AL_SAMPLE_8;
		}
		break;

		case 16: { /* Signed 16 bit audio data */
			spec->format = AUDIO_S16MSB;
			width = AL_SAMPLE_16;
		}
		break;

		default: {
			SDL_SetError("Unsupported audio format");
			return(-1);
		}
	}

	/* Update the fragment size as size in bytes */
	SDL_CalculateAudioSpec(spec);

	/* Set output frequency */
#ifdef OLD_IRIX_AUDIO
	audio_param[0] = AL_OUTPUT_RATE;
	audio_param[1] = spec->freq;
	if( ALsetparams(AL_DEFAULT_DEVICE, audio_param, 2) < 0 ) {
#else
	audio_param.param = AL_RATE;
	audio_param.value.i = spec->freq;
	if( alSetParams(AL_DEFAULT_OUTPUT, &audio_param, 1) < 0 ) {
#endif
		SDL_SetError("alSetParams failed");
		return(-1);
	}

	/* Open the audio port with the requested frequency */
	audio_port = NULL;
	audio_config = alNewConfig();
	if ( audio_config &&
	     (alSetSampFmt(audio_config, AL_SAMPFMT_TWOSCOMP) >= 0) &&
	     (alSetWidth(audio_config, width) >= 0) &&
	     (alSetQueueSize(audio_config, spec->samples*2) >= 0) &&
	     (alSetChannels(audio_config, spec->channels) >= 0) ) {
		audio_port = alOpenPort("SDL audio", "w", audio_config);
	}
	alFreeConfig(audio_config);
	if( audio_port == NULL ) {
		SDL_SetError("Unable to open audio port");
		return(-1);
	}

	/* Allocate mixing buffer */
	mixbuf = (Uint8 *)SDL_AllocAudioMem(spec->size);
	if ( mixbuf == NULL ) {
		SDL_OutOfMemory();
		return(-1);
	}
	memset(mixbuf, spec->silence, spec->size);

	/* We're ready to rock and roll. :-) */
	return(0);
}