view src/audio/baudio/SDL_beaudio.cc @ 4:4f6c5f021323

Date: Thu, 26 Apr 2001 10:46:23 +0200 From: Alexander Pipelka <pipelka@bms-austria.com> Subject: SDL ELO driver bugfix Hi Sam! We noticed that the ELO serial touchscreen controller is quite sensitive in terms of correct protocol handling. The current implementation cause some controllers to hangup after some time (> 24h). I think the attached patch should fix this (I ran my device more than 3 days without any hangups).
author Sam Lantinga <slouken@lokigames.com>
date Thu, 26 Apr 2001 16:54:56 +0000
parents 74212992fb08
children dabc453ce7f7
line wrap: on
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997  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
    slouken@devolution.com
*/

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

/* Allow access to the audio stream on BeOS */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <SoundPlayer.h>

#include "SDL_BeApp.h"

extern "C" {

#include "SDL_audio.h"
#include "SDL_audio_c.h"
#include "SDL_sysaudio.h"
#include "SDL_systhread_c.h"
#include "SDL_beaudio.h"


/* Audio driver functions */
static int BE_OpenAudio(_THIS, SDL_AudioSpec *spec);
static void BE_WaitAudio(_THIS);
static void BE_PlayAudio(_THIS);
static Uint8 *BE_GetAudioBuf(_THIS);
static void BE_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 *device;

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

	/* Set the function pointers */
	device->OpenAudio = BE_OpenAudio;
	device->WaitAudio = BE_WaitAudio;
	device->PlayAudio = BE_PlayAudio;
	device->GetAudioBuf = BE_GetAudioBuf;
	device->CloseAudio = BE_CloseAudio;

	device->free = Audio_DeleteDevice;

	return device;
}

AudioBootStrap BAUDIO_bootstrap = {
	"baudio", "BeOS BSoundPlayer",
	Audio_Available, Audio_CreateDevice
};

/* The BeOS callback for handling the audio buffer */
static void FillSound(void *device, void *stream, size_t len, 
					const media_raw_audio_format &format)
{
	SDL_AudioDevice *audio = (SDL_AudioDevice *)device;

	/* Silence the buffer, since it's ours */
	memset(stream, audio->spec.silence, len);

	/* Only do soemthing if audio is enabled */
	if ( ! audio->enabled )
		return;

	if ( ! audio->paused ) {
		if ( audio->convert.needed ) {
			SDL_mutexP(audio->mixer_lock);
			(*audio->spec.callback)(audio->spec.userdata,
				(Uint8 *)audio->convert.buf,audio->convert.len);
			SDL_mutexV(audio->mixer_lock);
			SDL_ConvertAudio(&audio->convert);
			memcpy(stream,audio->convert.buf,audio->convert.len_cvt);
		} else {
			SDL_mutexP(audio->mixer_lock);
			(*audio->spec.callback)(audio->spec.userdata,
						(Uint8 *)stream, len);
			SDL_mutexV(audio->mixer_lock);
		}
	}
	return;
}

/* Dummy functions -- we don't use thread-based audio */
void BE_WaitAudio(_THIS)
{
	return;
}
void BE_PlayAudio(_THIS)
{
	return;
}
Uint8 *BE_GetAudioBuf(_THIS)
{
	return(NULL);
}

void BE_CloseAudio(_THIS)
{
	if ( audio_obj ) {
		audio_obj->Stop();
		delete audio_obj;
		audio_obj = NULL;
	}

	/* Quit the Be Application, if there's nothing left to do */
	SDL_QuitBeApp();
}

int BE_OpenAudio(_THIS, SDL_AudioSpec *spec)
{
	media_raw_audio_format format;

	/* Initialize the Be Application, if it's not already started */
	if ( SDL_InitBeApp() < 0 ) {
		return(-1);
	}

	/* Parse the audio format and fill the Be raw audio format */
	format.frame_rate = (float)spec->freq;
	format.channel_count = spec->channels;
	switch (spec->format&~0x1000) {
		case AUDIO_S8:
			/* Signed 8-bit audio unsupported, convert to U8 */
			spec->format = AUDIO_U8;
		case AUDIO_U8:
			format.format = media_raw_audio_format::B_AUDIO_UCHAR;
			format.byte_order = 0;
			break;
		case AUDIO_U16:
			/* Unsigned 16-bit audio unsupported, convert to S16 */
			spec->format ^= 0x8000;
		case AUDIO_S16:
			format.format = media_raw_audio_format::B_AUDIO_SHORT;
			if ( spec->format & 0x1000 ) {
				format.byte_order = 1; /* Big endian */
			} else {
				format.byte_order = 2; /* Little endian */
			}
			break;
	}
	format.buffer_size = spec->samples;
	
	/* Calculate the final parameters for this audio specification */
	SDL_CalculateAudioSpec(spec);

	/* Subscribe to the audio stream (creates a new thread) */
	{ sigset_t omask;
		SDL_MaskSignals(&omask);
		audio_obj = new BSoundPlayer(&format, "SDL Audio", FillSound,
		                                                 NULL, _this);
		SDL_UnmaskSignals(&omask);
	}
	audio_obj->Start();
	audio_obj->SetHasData(true);

	/* We're running! */
	return(1);
}

};	/* Extern C */