SDL_nasaudio.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2019 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_audio_c.h"
#include "SDL_nasaudio.h"
static void (*NAS_AuCloseServer) (AuServer *);
static void (*NAS_AuNextEvent) (AuServer *, AuBool, AuEvent *);
static AuBool(*NAS_AuDispatchEvent) (AuServer *, AuEvent *);
static void (*NAS_AuHandleEvents) (AuServer *);
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 AuUint32 (*NAS_AuReadElement)
(AuServer *, AuFlowID, int, AuUint32, AuPointer, 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(AuHandleEvents);
SDL_NAS_SYM(AuCreateFlow);
SDL_NAS_SYM(AuStartFlow);
SDL_NAS_SYM(AuSetElements);
SDL_NAS_SYM(AuWriteElement);
SDL_NAS_SYM(AuReadElement);
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",
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 int
NAS_CaptureFromDevice(_THIS, void *buffer, int buflen)
{
struct SDL_PrivateAudioData *h = this->hidden;
int retval;
while (SDL_TRUE) {
/* just keep the event queue moving and the server chattering. */
NAS_AuHandleEvents(h->aud);
retval = (int) NAS_AuReadElement(h->aud, h->flow, 1, buflen, buffer, NULL);
/*printf("read %d capture bytes\n", (int) retval);*/
if (retval == 0) {
SDL_Delay(10); /* don't burn the CPU if we're waiting for data. */
} else {
break;
}
}
return retval;
}
static void
NAS_FlushCapture(_THIS)
{
struct SDL_PrivateAudioData *h = this->hidden;
AuUint32 total = 0;
AuUint32 br;
Uint8 buf[512];
do {
/* just keep the event queue moving and the server chattering. */
NAS_AuHandleEvents(h->aud);
br = NAS_AuReadElement(h->aud, h->flow, 1, sizeof (buf), buf, NULL);
/*printf("flushed %d capture bytes\n", (int) br);*/
total += br;
} while ((br == sizeof (buf)) && (total < this->spec.size));
}
static void
NAS_CloseDevice(_THIS)
{
if (this->hidden->aud) {
NAS_AuCloseServer(this->hidden->aud);
}
SDL_free(this->hidden->mixbuf);
SDL_free(this->hidden);
}
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)
{
SDL_AudioDevice *this = (SDL_AudioDevice *) hnd->data;
struct SDL_PrivateAudioData *h = this->hidden;
if (this->iscapture) {
return AuTrue; /* we don't (currently) care about any of this for capture devices */
}
switch (ev->type) {
case AuEventTypeElementNotify:
{
AuElementNotifyEvent *event = (AuElementNotifyEvent *) ev;
switch (event->kind) {
case AuElementNotifyKindLowWater:
if (h->buf_free >= 0) {
h->really += event->num_bytes;
gettimeofday(&h->last_tv, 0);
h->buf_free += event->num_bytes;
} else {
h->buf_free = event->num_bytes;
}
break;
case AuElementNotifyKindState:
switch (event->cur_state) {
case AuStatePause:
if (event->reason != AuReasonUser) {
if (h->buf_free >= 0) {
h->really += event->num_bytes;
gettimeofday(&h->last_tv, 0);
h->buf_free += event->num_bytes;
} else {
h->buf_free = event->num_bytes;
}
}
break;
}
}
}
}
return AuTrue;
}
static AuDeviceID
find_device(_THIS)
{
/* These "Au" things are all macros, not functions... */
struct SDL_PrivateAudioData *h = this->hidden;
const unsigned int devicekind = this->iscapture ? AuComponentKindPhysicalInput : AuComponentKindPhysicalOutput;
const int numdevs = AuServerNumDevices(h->aud);
const int nch = this->spec.channels;
int i;
/* Try to find exact match on channels first... */
for (i = 0; i < numdevs; i++) {
const AuDeviceAttributes *dev = AuServerDevice(h->aud, i);
if ((AuDeviceKind(dev) == devicekind) && (AuDeviceNumTracks(dev) == nch)) {
return AuDeviceIdentifier(dev);
}
}
/* Take anything, then... */
for (i = 0; i < numdevs; i++) {
const AuDeviceAttributes *dev = AuServerDevice(h->aud, i);
if (AuDeviceKind(dev) == devicekind) {
this->spec.channels = AuDeviceNumTracks(dev);
return AuDeviceIdentifier(dev);
}
}
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_zerop(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) {
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) {
return SDL_SetError("NAS: Couldn't open connection to NAS server");
}
this->hidden->dev = find_device(this);
if ((this->hidden->dev == AuNone)
|| (!(this->hidden->flow = NAS_AuCreateFlow(this->hidden->aud, 0)))) {
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);
if (iscapture) {
AuMakeElementImportDevice(elms, this->spec.freq, this->hidden->dev,
AuUnlimitedSamples, 0, NULL);
AuMakeElementExportClient(elms + 1, 0, this->spec.freq, format,
this->spec.channels, AuTrue, buffer_size,
buffer_size, 0, NULL);
} else {
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) this);
NAS_AuStartFlow(this->hidden->aud, this->hidden->flow, NULL);
/* Allocate mixing buffer */
if (!iscapture) {
this->hidden->mixlen = this->spec.size;
this->hidden->mixbuf = (Uint8 *) SDL_malloc(this->hidden->mixlen);
if (this->hidden->mixbuf == NULL) {
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->CaptureFromDevice = NAS_CaptureFromDevice;
impl->FlushCapture = NAS_FlushCapture;
impl->CloseDevice = NAS_CloseDevice;
impl->Deinitialize = NAS_Deinitialize;
impl->OnlyHasDefaultOutputDevice = 1;
impl->OnlyHasDefaultCaptureDevice = 1;
impl->HasCaptureSupport = SDL_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: */
format
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1572
SDL_memset
#define SDL_memset
Definition: SDL_dynapi_overrides.h:386
SDL_FirstAudioFormat
SDL_AudioFormat SDL_FirstAudioFormat(SDL_AudioFormat format)
Definition: SDL_audio.c:1647
SDL_GetError
#define SDL_GetError
Definition: SDL_dynapi_overrides.h:113
SDL_AudioSpec::channels
Uint8 channels
Definition: SDL_audio.h:182
SDL_AudioDriverImpl::HasCaptureSupport
int HasCaptureSupport
Definition: SDL_sysaudio.h:90
SDL_strlcpy
#define SDL_strlcpy
Definition: SDL_dynapi_overrides.h:394
AUDIO_U16LSB
#define AUDIO_U16LSB
Definition: SDL_audio.h:91
SDL_AudioDriverImpl::FlushCapture
void(* FlushCapture)(_THIS)
Definition: SDL_sysaudio.h:76
NULL
#define NULL
Definition: begin_code.h:167
handle
EGLImageKHR EGLint EGLint * handle
Definition: eglext.h:937
SDL_timer.h
SDL_zerop
#define SDL_zerop(x)
Definition: SDL_stdinc.h:417
SDL_AudioSpec::format
SDL_AudioFormat format
Definition: SDL_audio.h:181
SDL_AudioDriverImpl::OpenDevice
int(* OpenDevice)(_THIS, void *handle, const char *devname, int iscapture)
Definition: SDL_sysaudio.h:68
SDL_UnloadObject
#define SDL_UnloadObject
Definition: SDL_dynapi_overrides.h:234
SDL_PrivateAudioData::dev
AuDeviceID dev
Definition: SDL_nasaudio.h:42
SDL_NextAudioFormat
SDL_AudioFormat SDL_NextAudioFormat(void)
Definition: SDL_audio.c:1659
h
GLfloat GLfloat GLfloat GLfloat h
Definition: SDL_opengl_glext.h:1946
SDL_PrivateAudioData::iscapture
SDL_bool iscapture
Definition: SDL_qsa_audio.h:37
SDL_AudioFormat
Uint16 SDL_AudioFormat
Audio format flags.
Definition: SDL_audio.h:64
SDL_LoadObject
#define SDL_LoadObject
Definition: SDL_dynapi_overrides.h:232
AudioBootStrap
Definition: SDL_sysaudio.h:176
SDL_PrivateAudioData
Definition: SDL_alsa_audio.h:33
AUDIO_U8
#define AUDIO_U8
Definition: SDL_audio.h:89
SDL_AudioDriverImpl::WaitDevice
void(* WaitDevice)(_THIS)
Definition: SDL_sysaudio.h:72
len
GLenum GLsizei len
Definition: SDL_opengl_glext.h:2926
buf
GLenum GLuint GLenum GLsizei const GLchar * buf
Definition: SDL_opengl_glext.h:2480
event
struct _cl_event * event
Definition: SDL_opengl_glext.h:2649
buffer
GLuint buffer
Definition: SDL_opengl_glext.h:533
SDL_PrivateAudioData::aud
AuServer * aud
Definition: SDL_nasaudio.h:40
SDL_audio.h
retval
SDL_bool retval
Definition: testgamecontroller.c:65
SDL_PrivateAudioData::really
int really
Definition: SDL_nasaudio.h:49
SDL_AudioDriverImpl
Definition: SDL_sysaudio.h:65
SDL_free
#define SDL_free
Definition: SDL_dynapi_overrides.h:377
SDL_AudioDriverImpl::OnlyHasDefaultOutputDevice
int OnlyHasDefaultOutputDevice
Definition: SDL_sysaudio.h:91
NAS_bootstrap
AudioBootStrap NAS_bootstrap
addr
GLenum const void * addr
Definition: SDL_opengl_glext.h:7945
SDL_CalculateAudioSpec
void SDL_CalculateAudioSpec(SDL_AudioSpec *spec)
Definition: SDL_audio.c:1668
_THIS
#define _THIS
Definition: SDL_alsa_audio.h:31
SDL_AudioDriverImpl::PlayDevice
void(* PlayDevice)(_THIS)
Definition: SDL_sysaudio.h:73
SDL_Delay
#define SDL_Delay
Definition: SDL_dynapi_overrides.h:486
SDL_AudioSpec::freq
int freq
Definition: SDL_audio.h:180
SDL_AudioDriverImpl::OnlyHasDefaultCaptureDevice
int OnlyHasDefaultCaptureDevice
Definition: SDL_sysaudio.h:92
SDL_OutOfMemory
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
spec
SDL_AudioSpec spec
Definition: loopwave.c:31
SDL_AudioDriverImpl::CaptureFromDevice
int(* CaptureFromDevice)(_THIS, void *buffer, int buflen)
Definition: SDL_sysaudio.h:75
SDL_AudioSpec::size
Uint32 size
Definition: SDL_audio.h:186
SDL_TRUE
@ SDL_TRUE
Definition: SDL_stdinc.h:164
SDL_nasaudio.h
SDL_SetError
#define SDL_SetError
Definition: SDL_dynapi_overrides.h:30
SDL_LoadFunction
void * SDL_LoadFunction(void *handle, const char *name)
SDL_AudioDriverImpl::GetDeviceBuf
Uint8 *(* GetDeviceBuf)(_THIS)
Definition: SDL_sysaudio.h:74
AUDIO_S16MSB
#define AUDIO_S16MSB
Definition: SDL_audio.h:94
SDL_strlen
#define SDL_strlen
Definition: SDL_dynapi_overrides.h:393
AUDIO_S16LSB
#define AUDIO_S16LSB
Definition: SDL_audio.h:92
AUDIO_S8
#define AUDIO_S8
Definition: SDL_audio.h:90
SDL_malloc
#define SDL_malloc
Definition: SDL_dynapi_overrides.h:374
void
const SDL_PRINTF_FORMAT_STRING char int const SDL_PRINTF_FORMAT_STRING char int const SDL_PRINTF_FORMAT_STRING char int const SDL_PRINTF_FORMAT_STRING char const char const SDL_SCANF_FORMAT_STRING char return SDL_ThreadFunction const char void return Uint32 return Uint32 void
Definition: SDL_dynapi_procs.h:89
SDL_loadso.h
SDL_AudioDriverImpl::CloseDevice
void(* CloseDevice)(_THIS)
Definition: SDL_sysaudio.h:78
AUDIO_U16MSB
#define AUDIO_U16MSB
Definition: SDL_audio.h:93
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:50
SDL_AudioDevice
Definition: SDL_sysaudio.h:131
SDL_AudioDriverImpl::Deinitialize
void(* Deinitialize)(void)
Definition: SDL_sysaudio.h:82
Uint8
uint8_t Uint8
Definition: SDL_stdinc.h:179