RetroArch/audio/drivers/openal.c
2015-01-12 05:05:56 +01:00

272 lines
5.6 KiB
C

/* RetroArch - A frontend for libretro.
* Copyright (C) 2010-2014 - Hans-Kristian Arntzen
*
* RetroArch is free software: you can redistribute it and/or modify it under the terms
* of the GNU General Public License as published by the Free Software Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* RetroArch 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with RetroArch.
* If not, see <http://www.gnu.org/licenses/>.
*/
#include "../../driver.h"
#include "../../general.h"
#ifdef __APPLE__
#include <OpenAL/al.h>
#include <OpenAL/alc.h>
#else
#include <AL/al.h>
#include <AL/alc.h>
#endif
#include <time.h>
#include <string.h>
#ifdef _WIN32
#include <windows.h>
#endif
#define BUFSIZE 1024
typedef struct al
{
ALuint source;
ALuint *buffers;
ALuint *res_buf;
size_t res_ptr;
ALenum format;
size_t num_buffers;
int rate;
uint8_t tmpbuf[BUFSIZE];
size_t tmpbuf_ptr;
ALCdevice *handle;
ALCcontext *ctx;
bool nonblock;
bool is_paused;
} al_t;
static void al_free(void *data)
{
al_t *al = (al_t*)data;
if (!al)
return;
alSourceStop(al->source);
alDeleteSources(1, &al->source);
if (al->buffers)
alDeleteBuffers(al->num_buffers, al->buffers);
free(al->buffers);
free(al->res_buf);
alcMakeContextCurrent(NULL);
if (al->ctx)
alcDestroyContext(al->ctx);
if (al->handle)
alcCloseDevice(al->handle);
free(al);
}
static void *al_init(const char *device, unsigned rate, unsigned latency)
{
al_t *al;
(void)device;
al = (al_t*)calloc(1, sizeof(al_t));
if (!al)
return NULL;
al->handle = alcOpenDevice(NULL);
if (!al->handle)
goto error;
al->ctx = alcCreateContext(al->handle, NULL);
if (!al->ctx)
goto error;
alcMakeContextCurrent(al->ctx);
al->rate = rate;
/* We already use one buffer for tmpbuf. */
al->num_buffers = (latency * rate * 2 * sizeof(int16_t)) / (1000 * BUFSIZE) - 1;
if (al->num_buffers < 2)
al->num_buffers = 2;
RARCH_LOG("[OpenAL]: Using %u buffers of %u bytes.\n", (unsigned)al->num_buffers, BUFSIZE);
al->buffers = (ALuint*)calloc(al->num_buffers, sizeof(ALuint));
al->res_buf = (ALuint*)calloc(al->num_buffers, sizeof(ALuint));
if (al->buffers == NULL || al->res_buf == NULL)
goto error;
alGenSources(1, &al->source);
alGenBuffers(al->num_buffers, al->buffers);
memcpy(al->res_buf, al->buffers, al->num_buffers * sizeof(ALuint));
al->res_ptr = al->num_buffers;
return al;
error:
al_free(al);
return NULL;
}
static bool al_unqueue_buffers(al_t *al)
{
ALint val;
alGetSourcei(al->source, AL_BUFFERS_PROCESSED, &val);
if (val <= 0)
return false;
alSourceUnqueueBuffers(al->source, val, &al->res_buf[al->res_ptr]);
al->res_ptr += val;
return true;
}
static bool al_get_buffer(al_t *al, ALuint *buffer)
{
if (!al->res_ptr)
{
for (;;)
{
if (al_unqueue_buffers(al))
break;
if (al->nonblock)
return false;
// Must sleep as there is no proper blocking method. :(
rarch_sleep(1);
}
}
*buffer = al->res_buf[--al->res_ptr];
return true;
}
static size_t al_fill_internal_buf(al_t *al, const void *buf, size_t size)
{
size_t read_size = min(BUFSIZE - al->tmpbuf_ptr, size);
memcpy(al->tmpbuf + al->tmpbuf_ptr, buf, read_size);
al->tmpbuf_ptr += read_size;
return read_size;
}
static ssize_t al_write(void *data, const void *buf_, size_t size)
{
al_t *al = (al_t*)data;
const uint8_t *buf = (const uint8_t*)buf_;
size_t written = 0;
while (size)
{
ALint val;
ALuint buffer;
size_t rc = al_fill_internal_buf(al, buf, size);
written += rc;
buf += rc;
size -= rc;
if (al->tmpbuf_ptr != BUFSIZE)
break;
if (!al_get_buffer(al, &buffer))
break;
alBufferData(buffer, AL_FORMAT_STEREO16, al->tmpbuf, BUFSIZE, al->rate);
al->tmpbuf_ptr = 0;
alSourceQueueBuffers(al->source, 1, &buffer);
if (alGetError() != AL_NO_ERROR)
return -1;
alGetSourcei(al->source, AL_SOURCE_STATE, &val);
if (val != AL_PLAYING)
alSourcePlay(al->source);
if (alGetError() != AL_NO_ERROR)
return -1;
}
return written;
}
static bool al_stop(void *data)
{
al_t *al = (al_t*)data;
if (al)
al->is_paused = true;
return true;
}
static bool al_alive(void *data)
{
al_t *al = (al_t*)data;
if (!al)
return false;
return !al->is_paused;
}
static void al_set_nonblock_state(void *data, bool state)
{
al_t *al = (al_t*)data;
if (al)
al->nonblock = state;
}
static bool al_start(void *data)
{
al_t *al = (al_t*)data;
if (al)
al->is_paused = false;
return true;
}
static size_t al_write_avail(void *data)
{
al_t *al = (al_t*)data;
al_unqueue_buffers(al);
return al->res_ptr * BUFSIZE + (BUFSIZE - al->tmpbuf_ptr);
}
static size_t al_buffer_size(void *data)
{
al_t *al = (al_t*)data;
return (al->num_buffers + 1) * BUFSIZE; /* Also got tmpbuf. */
}
static bool al_use_float(void *data)
{
(void)data;
return false;
}
audio_driver_t audio_openal = {
al_init,
al_write,
al_stop,
al_start,
al_alive,
al_set_nonblock_state,
al_free,
al_use_float,
"openal",
al_write_avail,
al_buffer_size,
};