SDL_nasaudio.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "../../SDL_internal.h"
#if SDL_AUDIO_DRIVER_NAS
/* Allow access to a raw mixing buffer */
#include <signal.h>
#include <unistd.h>
#include "SDL_timer.h"
#include "SDL_audio.h"
#include "SDL_loadso.h"
#include "../SDL_audiomem.h"
#include "../SDL_audio_c.h"
#include "SDL_nasaudio.h"
static struct SDL_PrivateAudioData *this2 = NULL;
static void (*NAS_AuCloseServer) (AuServer *);
static void (*NAS_AuNextEvent) (AuServer *, AuBool, AuEvent *);
static AuBool(*NAS_AuDispatchEvent) (AuServer *, AuEvent *);
static AuFlowID(*NAS_AuCreateFlow) (AuServer *, AuStatus *);
static void (*NAS_AuStartFlow) (AuServer *, AuFlowID, AuStatus *);
static void (*NAS_AuSetElements)
(AuServer *, AuFlowID, AuBool, int, AuElement *, AuStatus *);
static void (*NAS_AuWriteElement)
(AuServer *, AuFlowID, int, AuUint32, AuPointer, AuBool, AuStatus *);
static AuServer *(*NAS_AuOpenServer)
(_AuConst char *, int, _AuConst char *, int, _AuConst char *, char **);
static AuEventHandlerRec *(*NAS_AuRegisterEventHandler)
(AuServer *, AuMask, int, AuID, AuEventHandlerCallback, AuPointer);
#ifdef SDL_AUDIO_DRIVER_NAS_DYNAMIC
static const char *nas_library = SDL_AUDIO_DRIVER_NAS_DYNAMIC;
static void *nas_handle = NULL;
static int
load_nas_sym(const char *fn, void **addr)
{
*addr = SDL_LoadFunction(nas_handle, fn);
if (*addr == NULL) {
return 0;
}
return 1;
}
/* cast funcs to char* first, to please GCC's strict aliasing rules. */
#define SDL_NAS_SYM(x) \
if (!load_nas_sym(#x, (void **) (char *) &NAS_##x)) return -1
#else
#define SDL_NAS_SYM(x) NAS_##x = x
#endif
static int
load_nas_syms(void)
{
SDL_NAS_SYM(AuCloseServer);
SDL_NAS_SYM(AuNextEvent);
SDL_NAS_SYM(AuDispatchEvent);
SDL_NAS_SYM(AuCreateFlow);
SDL_NAS_SYM(AuStartFlow);
SDL_NAS_SYM(AuSetElements);
SDL_NAS_SYM(AuWriteElement);
SDL_NAS_SYM(AuOpenServer);
SDL_NAS_SYM(AuRegisterEventHandler);
return 0;
}
#undef SDL_NAS_SYM
#ifdef SDL_AUDIO_DRIVER_NAS_DYNAMIC
static void
UnloadNASLibrary(void)
{
if (nas_handle != NULL) {
SDL_UnloadObject(nas_handle);
nas_handle = NULL;
}
}
static int
LoadNASLibrary(void)
{
int retval = 0;
if (nas_handle == NULL) {
nas_handle = SDL_LoadObject(nas_library);
if (nas_handle == NULL) {
/* Copy error string so we can use it in a new SDL_SetError(). */
const char *origerr = SDL_GetError();
const size_t len = SDL_strlen(origerr) + 1;
char *err = (char *) alloca(len);
SDL_strlcpy(err, origerr, len);
retval = -1;
SDL_SetError("NAS: SDL_LoadObject('%s') failed: %s\n",
nas_library, err);
} else {
retval = load_nas_syms();
if (retval < 0) {
UnloadNASLibrary();
}
}
}
return retval;
}
#else
static void
UnloadNASLibrary(void)
{
}
static int
LoadNASLibrary(void)
{
load_nas_syms();
return 0;
}
#endif /* SDL_AUDIO_DRIVER_NAS_DYNAMIC */
/* This function waits until it is possible to write a full sound buffer */
static void
NAS_WaitDevice(_THIS)
{
while (this->hidden->buf_free < this->hidden->mixlen) {
AuEvent ev;
NAS_AuNextEvent(this->hidden->aud, AuTrue, &ev);
NAS_AuDispatchEvent(this->hidden->aud, &ev);
}
}
static void
NAS_PlayDevice(_THIS)
{
while (this->hidden->mixlen > this->hidden->buf_free) {
/*
* We think the buffer is full? Yikes! Ask the server for events,
* in the hope that some of them is LowWater events telling us more
* of the buffer is free now than what we think.
*/
AuEvent ev;
NAS_AuNextEvent(this->hidden->aud, AuTrue, &ev);
NAS_AuDispatchEvent(this->hidden->aud, &ev);
}
this->hidden->buf_free -= this->hidden->mixlen;
/* Write the audio data */
NAS_AuWriteElement(this->hidden->aud, this->hidden->flow, 0,
this->hidden->mixlen, this->hidden->mixbuf, AuFalse,
NULL);
this->hidden->written += this->hidden->mixlen;
#ifdef DEBUG_AUDIO
fprintf(stderr, "Wrote %d bytes of audio data\n", this->hidden->mixlen);
#endif
}
static Uint8 *
NAS_GetDeviceBuf(_THIS)
{
return (this->hidden->mixbuf);
}
static void
NAS_CloseDevice(_THIS)
{
if (this->hidden != NULL) {
SDL_FreeAudioMem(this->hidden->mixbuf);
this->hidden->mixbuf = NULL;
if (this->hidden->aud) {
NAS_AuCloseServer(this->hidden->aud);
this->hidden->aud = 0;
}
SDL_free(this->hidden);
this2 = this->hidden = NULL;
}
}
static unsigned char
sdlformat_to_auformat(unsigned int fmt)
{
switch (fmt) {
case AUDIO_U8:
return AuFormatLinearUnsigned8;
case AUDIO_S8:
return AuFormatLinearSigned8;
case AUDIO_U16LSB:
return AuFormatLinearUnsigned16LSB;
case AUDIO_U16MSB:
return AuFormatLinearUnsigned16MSB;
case AUDIO_S16LSB:
return AuFormatLinearSigned16LSB;
case AUDIO_S16MSB:
return AuFormatLinearSigned16MSB;
}
return AuNone;
}
static AuBool
event_handler(AuServer * aud, AuEvent * ev, AuEventHandlerRec * hnd)
{
switch (ev->type) {
case AuEventTypeElementNotify:
{
AuElementNotifyEvent *event = (AuElementNotifyEvent *) ev;
switch (event->kind) {
case AuElementNotifyKindLowWater:
if (this2->buf_free >= 0) {
this2->really += event->num_bytes;
gettimeofday(&this2->last_tv, 0);
this2->buf_free += event->num_bytes;
} else {
this2->buf_free = event->num_bytes;
}
break;
case AuElementNotifyKindState:
switch (event->cur_state) {
case AuStatePause:
if (event->reason != AuReasonUser) {
if (this2->buf_free >= 0) {
this2->really += event->num_bytes;
gettimeofday(&this2->last_tv, 0);
this2->buf_free += event->num_bytes;
} else {
this2->buf_free = event->num_bytes;
}
}
break;
}
}
}
}
return AuTrue;
}
static AuDeviceID
find_device(_THIS, int nch)
{
/* These "Au" things are all macros, not functions... */
int i;
for (i = 0; i < AuServerNumDevices(this->hidden->aud); i++) {
if ((AuDeviceKind(AuServerDevice(this->hidden->aud, i)) ==
AuComponentKindPhysicalOutput) &&
AuDeviceNumTracks(AuServerDevice(this->hidden->aud, i)) == nch) {
return AuDeviceIdentifier(AuServerDevice(this->hidden->aud, i));
}
}
return AuNone;
}
static int
NAS_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
{
AuElement elms[3];
int buffer_size;
SDL_AudioFormat test_format, format;
/* Initialize all variables that we clean on shutdown */
this->hidden = (struct SDL_PrivateAudioData *)
SDL_malloc((sizeof *this->hidden));
if (this->hidden == NULL) {
return SDL_OutOfMemory();
}
SDL_memset(this->hidden, 0, (sizeof *this->hidden));
/* Try for a closest match on audio format */
format = 0;
for (test_format = SDL_FirstAudioFormat(this->spec.format);
!format && test_format;) {
format = sdlformat_to_auformat(test_format);
if (format == AuNone) {
test_format = SDL_NextAudioFormat();
}
}
if (format == 0) {
NAS_CloseDevice(this);
return SDL_SetError("NAS: Couldn't find any hardware audio formats");
}
this->spec.format = test_format;
this->hidden->aud = NAS_AuOpenServer("", 0, NULL, 0, NULL, NULL);
if (this->hidden->aud == 0) {
NAS_CloseDevice(this);
return SDL_SetError("NAS: Couldn't open connection to NAS server");
}
this->hidden->dev = find_device(this, this->spec.channels);
if ((this->hidden->dev == AuNone)
|| (!(this->hidden->flow = NAS_AuCreateFlow(this->hidden->aud, 0)))) {
NAS_CloseDevice(this);
return SDL_SetError("NAS: Couldn't find a fitting device on NAS server");
}
buffer_size = this->spec.freq;
if (buffer_size < 4096)
buffer_size = 4096;
if (buffer_size > 32768)
buffer_size = 32768; /* So that the buffer won't get unmanageably big. */
/* Calculate the final parameters for this audio specification */
SDL_CalculateAudioSpec(&this->spec);
this2 = this->hidden;
AuMakeElementImportClient(elms, this->spec.freq, format,
this->spec.channels, AuTrue, buffer_size,
buffer_size / 4, 0, NULL);
AuMakeElementExportDevice(elms + 1, 0, this->hidden->dev, this->spec.freq,
AuUnlimitedSamples, 0, NULL);
NAS_AuSetElements(this->hidden->aud, this->hidden->flow, AuTrue, 2, elms,
NULL);
NAS_AuRegisterEventHandler(this->hidden->aud, AuEventHandlerIDMask, 0,
this->hidden->flow, event_handler,
(AuPointer) NULL);
NAS_AuStartFlow(this->hidden->aud, this->hidden->flow, NULL);
/* Allocate mixing buffer */
this->hidden->mixlen = this->spec.size;
this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->hidden->mixlen);
if (this->hidden->mixbuf == NULL) {
NAS_CloseDevice(this);
return SDL_OutOfMemory();
}
SDL_memset(this->hidden->mixbuf, this->spec.silence, this->spec.size);
/* We're ready to rock and roll. :-) */
return 0;
}
static void
NAS_Deinitialize(void)
{
UnloadNASLibrary();
}
static int
NAS_Init(SDL_AudioDriverImpl * impl)
{
if (LoadNASLibrary() < 0) {
return 0;
} else {
AuServer *aud = NAS_AuOpenServer("", 0, NULL, 0, NULL, NULL);
if (aud == NULL) {
SDL_SetError("NAS: AuOpenServer() failed (no audio server?)");
return 0;
}
NAS_AuCloseServer(aud);
}
/* Set the function pointers */
impl->OpenDevice = NAS_OpenDevice;
impl->PlayDevice = NAS_PlayDevice;
impl->WaitDevice = NAS_WaitDevice;
impl->GetDeviceBuf = NAS_GetDeviceBuf;
impl->CloseDevice = NAS_CloseDevice;
impl->Deinitialize = NAS_Deinitialize;
impl->OnlyHasDefaultOutputDevice = 1; /* !!! FIXME: is this true? */
return 1; /* this audio target is available. */
}
AudioBootStrap NAS_bootstrap = {
"nas", "Network Audio System", NAS_Init, 0
};
#endif /* SDL_AUDIO_DRIVER_NAS */
/* vi: set ts=4 sw=4 expandtab: */
SDL_strlcpy
#define SDL_strlcpy
Definition: SDL_dynapi_overrides.h:400
format
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1565
SDL_GetError
#define SDL_GetError
Definition: SDL_dynapi_overrides.h:119
SDL_FirstAudioFormat
SDL_AudioFormat SDL_FirstAudioFormat(SDL_AudioFormat format)
Definition: SDL_audio.c:1398
SDL_PrivateAudioData::really
int really
Definition: SDL_nasaudio.h:49
AUDIO_U16LSB
#define AUDIO_U16LSB
Definition: SDL_audio.h:91
SDL_PrivateAudioData::aud
AuServer * aud
Definition: SDL_nasaudio.h:40
SDL_FreeAudioMem
#define SDL_FreeAudioMem
Definition: SDL_audiomem.h:24
SDL_PrivateAudioData::iscapture
int iscapture
Definition: SDL_qsa_audio.h:37
SDL_AudioDriverImpl::PlayDevice
void(* PlayDevice)(_THIS)
Definition: SDL_sysaudio.h:75
SDL_AudioDriverImpl::WaitDevice
void(* WaitDevice)(_THIS)
Definition: SDL_sysaudio.h:74
SDL_AudioFormat
Uint16 SDL_AudioFormat
Audio format flags.
Definition: SDL_audio.h:64
SDL_LoadObject
#define SDL_LoadObject
Definition: SDL_dynapi_overrides.h:238
SDL_UnloadObject
#define SDL_UnloadObject
Definition: SDL_dynapi_overrides.h:240
SDL_PrivateAudioData
Definition: SDL_alsa_audio.h:33
len
GLenum GLsizei len
Definition: SDL_opengl_glext.h:2926
SDL_NextAudioFormat
SDL_AudioFormat SDL_NextAudioFormat(void)
Definition: SDL_audio.c:1410
spec
SDL_AudioSpec spec
Definition: loopwave.c:35
retval
SDL_bool retval
Definition: testgamecontroller.c:65
AUDIO_U8
#define AUDIO_U8
Definition: SDL_audio.h:89
AudioBootStrap
Definition: SDL_sysaudio.h:189
SDL_AudioDriverImpl::OnlyHasDefaultOutputDevice
int OnlyHasDefaultOutputDevice
Definition: SDL_sysaudio.h:92
SDL_AudioSpec::freq
int freq
Definition: SDL_audio.h:170
SDL_AudioSpec::channels
Uint8 channels
Definition: SDL_audio.h:172
_THIS
#define _THIS
Definition: SDL_alsa_audio.h:31
Uint8
uint8_t Uint8
An unsigned 8-bit integer type.
Definition: SDL_stdinc.h:139
event
struct _cl_event * event
Definition: SDL_opengl_glext.h:2649
SDL_free
void SDL_free(void *mem)
addr
GLenum const void * addr
Definition: SDL_opengl_glext.h:7945
SDL_AudioDriverImpl
Definition: SDL_sysaudio.h:69
SDL_AudioDriverImpl::Deinitialize
void(* Deinitialize)(void)
Definition: SDL_sysaudio.h:83
SDL_CalculateAudioSpec
void SDL_CalculateAudioSpec(SDL_AudioSpec *spec)
Definition: SDL_audio.c:1419
SDL_AllocAudioMem
#define SDL_AllocAudioMem
Definition: SDL_audiomem.h:23
NAS_bootstrap
AudioBootStrap NAS_bootstrap
SDL_AudioSpec::size
Uint32 size
Definition: SDL_audio.h:176
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:42
SDL_AudioDriverImpl::OpenDevice
int(* OpenDevice)(_THIS, void *handle, const char *devname, int iscapture)
Definition: SDL_sysaudio.h:72
NULL
#define NULL
Definition: begin_code.h:143
SDL_OutOfMemory
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
SDL_SetError
#define SDL_SetError
Definition: SDL_dynapi_overrides.h:36
SDL_loadso.h
void
SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char const char SDL_SCANF_FORMAT_STRING const char return SDL_ThreadFunction const char void return Uint32 return Uint32 void
Definition: SDL_dynapi_procs.h:93
SDL_AudioDriverImpl::CloseDevice
void(* CloseDevice)(_THIS)
Definition: SDL_sysaudio.h:79
SDL_PrivateAudioData::buf_free
int buf_free
Definition: SDL_nasaudio.h:52
AUDIO_S16MSB
#define AUDIO_S16MSB
Definition: SDL_audio.h:94
SDL_audio.h
SDL_strlen
#define SDL_strlen
Definition: SDL_dynapi_overrides.h:399
SDL_AudioSpec::format
SDL_AudioFormat format
Definition: SDL_audio.h:171
AUDIO_S16LSB
#define AUDIO_S16LSB
Definition: SDL_audio.h:92
SDL_AudioDriverImpl::GetDeviceBuf
Uint8 *(* GetDeviceBuf)(_THIS)
Definition: SDL_sysaudio.h:77
SDL_malloc
#define SDL_malloc
Definition: SDL_dynapi_overrides.h:380
SDL_nasaudio.h
SDL_LoadFunction
void * SDL_LoadFunction(void *handle, const char *name)
SDL_timer.h
AUDIO_S8
#define AUDIO_S8
Definition: SDL_audio.h:90
SDL_PrivateAudioData::last_tv
struct timeval last_tv
Definition: SDL_nasaudio.h:51
SDL_memset
#define SDL_memset
Definition: SDL_dynapi_overrides.h:392
AUDIO_U16MSB
#define AUDIO_U16MSB
Definition: SDL_audio.h:93