/*

SDL - Simple DirectMedia Layer

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Lesser General Public

License as published by the Free Software Foundation; either

version 2.1 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

Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public

License along with this library; if not, write to the Free Software

Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

Stéphan Kochen

stephan@kochen.nl

Based on parts of the ALSA and ESounD output drivers.

*/

#include "SDL_config.h"

/* Allow access to an PulseAudio network stream mixing buffer */

#include <sys/types.h>

#include <unistd.h>

#include <signal.h>

#include <errno.h>

#include <pulse/simple.h>

#include "SDL_timer.h"

#include "SDL_audio.h"

#include "../SDL_audiomem.h"

#include "../SDL_audio_c.h"

#include "../SDL_audiodev_c.h"

#include "SDL_pulseaudio.h"

#ifdef SDL_AUDIO_DRIVER_PULSE_DYNAMIC

#include "SDL_name.h"

#include "SDL_loadso.h"

#else

#define SDL_NAME(X) X

#endif

/* The tag name used by the driver */

#define PULSE_DRIVER_NAME "pulse"

/* Audio driver functions */

static int PULSE_OpenAudio(_THIS, SDL_AudioSpec *spec);

static void PULSE_WaitAudio(_THIS);

static void PULSE_PlayAudio(_THIS);

static Uint8 *PULSE_GetAudioBuf(_THIS);

static void PULSE_CloseAudio(_THIS);

#ifdef SDL_AUDIO_DRIVER_PULSE_DYNAMIC

static const char *pulse_library = SDL_AUDIO_DRIVER_PULSE_DYNAMIC;

static void *pulse_handle = NULL;

static int pulse_loaded = 0;

static pa_simple* (*SDL_NAME(pa_simple_new))(

const char *server,

const char *name,

pa_stream_direction_t dir,

const char *dev,

const char *stream_name,

const pa_sample_spec *ss,

const pa_channel_map *map,

const pa_buffer_attr *attr,

int *error

);

static void (*SDL_NAME(pa_simple_free))(pa_simple *s);

static int (*SDL_NAME(pa_simple_drain))(pa_simple *s, int *error);

static int (*SDL_NAME(pa_simple_write))(

pa_simple *s,

const void *data,

size_t length,

);

static pa_channel_map* (*SDL_NAME(pa_channel_map_init_auto))(

pa_channel_map *m,

unsigned channels,

pa_channel_map_def_t def

);

static struct {

const char *name;

void **func;

} pulse_functions[] = {

{ "pa_simple_new",

(void **)&SDL_NAME(pa_simple_new) },

{ "pa_simple_free",

(void **)&SDL_NAME(pa_simple_free) },

{ "pa_simple_drain",

(void **)&SDL_NAME(pa_simple_drain) },

{ "pa_simple_write",

(void **)&SDL_NAME(pa_simple_write) },

{ "pa_channel_map_init_auto",

(void **)&SDL_NAME(pa_channel_map_init_auto) },

};

static void UnloadPulseLibrary()

{

if ( pulse_loaded ) {

SDL_UnloadObject(pulse_handle);

pulse_handle = NULL;

pulse_loaded = 0;

}

}

static int LoadPulseLibrary(void)

{

int i, retval = -1;

pulse_handle = SDL_LoadObject(pulse_library);

if ( pulse_handle ) {

pulse_loaded = 1;

retval = 0;

for ( i=0; i<SDL_arraysize(pulse_functions); ++i ) {

*pulse_functions[i].func = SDL_LoadFunction(pulse_handle, pulse_functions[i].name);

if ( !*pulse_functions[i].func ) {

retval = -1;

UnloadPulseLibrary();

break;

}

}

}

return retval;

}

#else

static void UnloadPulseLibrary()

{

return;

}

static int LoadPulseLibrary(void)

{

return 0;

}

#endif /* SDL_AUDIO_DRIVER_PULSE_DYNAMIC */

/* Audio driver bootstrap functions */

static int Audio_Available(void)

{

pa_sample_spec paspec;

pa_simple *connection;

int available;

available = 0;

if ( LoadPulseLibrary() < 0 ) {

return available;

}

/* Connect with a dummy format. */

paspec.format = PA_SAMPLE_U8;

paspec.rate = 11025;

paspec.channels = 1;

connection = SDL_NAME(pa_simple_new)(

"Test stream", /* application name */

PA_STREAM_PLAYBACK, /* playback mode */

"Simple DirectMedia Layer", /* stream description */

&paspec, /* sample format spec */

NULL, /* channel map */

NULL, /* buffering attributes */

NULL /* error code */

);

if ( connection != NULL ) {

available = 1;

SDL_NAME(pa_simple_free)(connection);

}

UnloadPulseLibrary();

return(available);

}

static void Audio_DeleteDevice(SDL_AudioDevice *device)

{

SDL_free(device->hidden);

SDL_free(device);

UnloadPulseLibrary();

}

static SDL_AudioDevice *Audio_CreateDevice(int devindex)

{

SDL_AudioDevice *this;

/* Initialize all variables that we clean on shutdown */

LoadPulseLibrary();

this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice));

if ( this ) {

SDL_memset(this, 0, (sizeof *this));

this->hidden = (struct SDL_PrivateAudioData *)

SDL_malloc((sizeof *this->hidden));

}

if ( (this == NULL) || (this->hidden == NULL) ) {

SDL_OutOfMemory();

if ( this ) {

SDL_free(this);

}

return(0);

}

SDL_memset(this->hidden, 0, (sizeof *this->hidden));

/* Set the function pointers */

this->OpenAudio = PULSE_OpenAudio;

this->WaitAudio = PULSE_WaitAudio;

this->PlayAudio = PULSE_PlayAudio;

this->GetAudioBuf = PULSE_GetAudioBuf;

this->CloseAudio = PULSE_CloseAudio;

this->free = Audio_DeleteDevice;

return this;

}

AudioBootStrap PULSE_bootstrap = {

PULSE_DRIVER_NAME, "PulseAudio",

Audio_Available, Audio_CreateDevice

};

/* This function waits until it is possible to write a full sound buffer */

static void PULSE_WaitAudio(_THIS)

{

/* Check to see if the thread-parent process is still alive */

{ static int cnt = 0;

that use a different process id for each thread.

*/

if (parent && (((++cnt)%10) == 0)) { /* Check every 10 loops */

if ( kill(parent, 0) < 0 ) {

this->enabled = 0;

}

}

}

}

static void PULSE_PlayAudio(_THIS)

{

/* Write the audio data */

if ( SDL_NAME(pa_simple_write)(stream, mixbuf, mixlen, NULL) != 0 )

{

this->enabled = 0;

}

}

static Uint8 *PULSE_GetAudioBuf(_THIS)

{

return(mixbuf);

}

static void PULSE_CloseAudio(_THIS)

{

if ( mixbuf != NULL ) {

SDL_FreeAudioMem(mixbuf);

mixbuf = NULL;

}

if ( stream != NULL ) {

SDL_NAME(pa_simple_drain)(stream, NULL);

SDL_NAME(pa_simple_free)(stream);

stream = NULL;

}

}

/* Try to get the name of the program */

static char *get_progname(void)

{

char *progname = NULL;

#ifdef __LINUX__

FILE *fp;

static char temp[BUFSIZ];

SDL_snprintf(temp, SDL_arraysize(temp), "/proc/%d/cmdline", getpid());

fp = fopen(temp, "r");

if ( fp != NULL ) {

if ( fgets(temp, sizeof(temp)-1, fp) ) {

progname = SDL_strrchr(temp, '/');

if ( progname == NULL ) {

progname = temp;

} else {

progname = progname+1;

}

}

fclose(fp);

}

#endif

return(progname);

}

static int PULSE_OpenAudio(_THIS, SDL_AudioSpec *spec)

{

Uint16 test_format;

pa_sample_spec paspec;

pa_buffer_attr paattr;

pa_channel_map pacmap;

paspec.format = PA_SAMPLE_INVALID;

for ( test_format = SDL_FirstAudioFormat(spec->format); test_format; ) {

switch ( test_format ) {

case AUDIO_U8:

paspec.format = PA_SAMPLE_U8;

break;

case AUDIO_S16LSB:

paspec.format = PA_SAMPLE_S16LE;

break;

case AUDIO_S16MSB:

paspec.format = PA_SAMPLE_S16BE;

break;

}

if ( paspec.format != PA_SAMPLE_INVALID )

break;

}

if (paspec.format == PA_SAMPLE_INVALID ) {

SDL_SetError("Couldn't find any suitable audio formats");

return(-1);

}

spec->format = test_format;

paspec.channels = spec->channels;

paspec.rate = spec->freq;

/* Calculate the final parameters for this audio specification */

SDL_CalculateAudioSpec(spec);

/* Allocate mixing buffer */

mixlen = spec->size;

mixbuf = (Uint8 *)SDL_AllocAudioMem(mixlen);

if ( mixbuf == NULL ) {

return(-1);

}

SDL_memset(mixbuf, spec->silence, spec->size);

paattr.prebuf = mixlen*2;

paattr.maxlength = mixlen*2;

/* The SDL ALSA output hints us that we use Windows' channel mapping */

/* http://bugzilla.libsdl.org/show_bug.cgi?id=110 */

SDL_NAME(pa_channel_map_init_auto)(

&pacmap, spec->channels, PA_CHANNEL_MAP_WAVEEX);

/* Connect to the PulseAudio server */

stream = SDL_NAME(pa_simple_new)(

get_progname(), /* application name */

PA_STREAM_PLAYBACK, /* playback mode */

"Simple DirectMedia Layer", /* stream description */

&paspec, /* sample format spec */

&pacmap, /* channel map */

&paattr, /* buffering attributes */

NULL /* error code */

);

if ( stream == NULL ) {

PULSE_CloseAudio(this);

SDL_SetError("Could not connect to PulseAudio");

return(-1);

}

/* Get the parent process id (we're the parent of the audio thread) */

parent = getpid();

return(0);

}