SDL_sunaudio.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2018 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_SUNAUDIO
/* Allow access to a raw mixing buffer */
#include <fcntl.h>
#include <errno.h>
#ifdef __NETBSD__
#include <sys/ioctl.h>
#include <sys/audioio.h>
#endif
#ifdef __SVR4
#include <sys/audioio.h>
#else
#include <sys/time.h>
#include <sys/types.h>
#endif
#include <unistd.h>
#include "SDL_timer.h"
#include "SDL_audio.h"
#include "../../core/unix/SDL_poll.h"
#include "../SDL_audio_c.h"
#include "../SDL_audiodev_c.h"
#include "SDL_sunaudio.h"
/* Open the audio device for playback, and don't block if busy */
#if defined(AUDIO_GETINFO) && !defined(AUDIO_GETBUFINFO)
#define AUDIO_GETBUFINFO AUDIO_GETINFO
#endif
/* Audio driver functions */
static Uint8 snd2au(int sample);
/* Audio driver bootstrap functions */
static void
SUNAUDIO_DetectDevices(void)
{
SDL_EnumUnixAudioDevices(1, (int (*)(int)) NULL);
}
#ifdef DEBUG_AUDIO
void
CheckUnderflow(_THIS)
{
#ifdef AUDIO_GETBUFINFO
audio_info_t info;
int left;
ioctl(this->hidden->audio_fd, AUDIO_GETBUFINFO, &info);
left = (this->hidden->written - info.play.samples);
if (this->hidden->written && (left == 0)) {
fprintf(stderr, "audio underflow!\n");
}
#endif
}
#endif
static void
SUNAUDIO_WaitDevice(_THIS)
{
#ifdef AUDIO_GETBUFINFO
#define SLEEP_FUDGE 10 /* 10 ms scheduling fudge factor */
audio_info_t info;
Sint32 left;
ioctl(this->hidden->audio_fd, AUDIO_GETBUFINFO, &info);
left = (this->hidden->written - info.play.samples);
if (left > this->hidden->fragsize) {
Sint32 sleepy;
sleepy = ((left - this->hidden->fragsize) / this->hidden->frequency);
sleepy -= SLEEP_FUDGE;
if (sleepy > 0) {
SDL_Delay(sleepy);
}
}
#else
SDL_IOReady(this->hidden->audio_fd, SDL_TRUE, -1);
#endif
}
static void
SUNAUDIO_PlayDevice(_THIS)
{
/* Write the audio data */
if (this->hidden->ulaw_only) {
/* Assuming that this->spec.freq >= 8000 Hz */
int accum, incr, pos;
Uint8 *aubuf;
accum = 0;
incr = this->spec.freq / 8;
aubuf = this->hidden->ulaw_buf;
switch (this->hidden->audio_fmt & 0xFF) {
case 8:
{
Uint8 *sndbuf;
sndbuf = this->hidden->mixbuf;
for (pos = 0; pos < this->hidden->fragsize; ++pos) {
*aubuf = snd2au((0x80 - *sndbuf) * 64);
accum += incr;
while (accum > 0) {
accum -= 1000;
sndbuf += 1;
}
aubuf += 1;
}
}
break;
case 16:
{
Sint16 *sndbuf;
sndbuf = (Sint16 *) this->hidden->mixbuf;
for (pos = 0; pos < this->hidden->fragsize; ++pos) {
*aubuf = snd2au(*sndbuf / 4);
accum += incr;
while (accum > 0) {
accum -= 1000;
sndbuf += 1;
}
aubuf += 1;
}
}
break;
}
#ifdef DEBUG_AUDIO
CheckUnderflow(this);
#endif
if (write(this->hidden->audio_fd, this->hidden->ulaw_buf,
this->hidden->fragsize) < 0) {
/* Assume fatal error, for now */
SDL_OpenedAudioDeviceDisconnected(this);
}
this->hidden->written += this->hidden->fragsize;
} else {
#ifdef DEBUG_AUDIO
CheckUnderflow(this);
#endif
if (write(this->hidden->audio_fd, this->hidden->mixbuf,
this->spec.size) < 0) {
/* Assume fatal error, for now */
SDL_OpenedAudioDeviceDisconnected(this);
}
this->hidden->written += this->hidden->fragsize;
}
}
static Uint8 *
SUNAUDIO_GetDeviceBuf(_THIS)
{
return (this->hidden->mixbuf);
}
static void
SUNAUDIO_CloseDevice(_THIS)
{
SDL_free(this->hidden->ulaw_buf);
if (this->hidden->audio_fd >= 0) {
close(this->hidden->audio_fd);
}
SDL_free(this->hidden->mixbuf);
SDL_free(this->hidden);
}
static int
SUNAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
{
#ifdef AUDIO_SETINFO
int enc;
#endif
int desired_freq = 0;
const int flags = ((iscapture) ? OPEN_FLAGS_INPUT : OPEN_FLAGS_OUTPUT);
SDL_AudioFormat format = 0;
audio_info_t info;
/* We don't care what the devname is...we'll try to open anything. */
/* ...but default to first name in the list... */
if (devname == NULL) {
devname = SDL_GetAudioDeviceName(0, iscapture);
if (devname == NULL) {
return SDL_SetError("No such audio device");
}
}
/* 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);
/* Open the audio device */
this->hidden->audio_fd = open(devname, flags, 0);
if (this->hidden->audio_fd < 0) {
return SDL_SetError("Couldn't open %s: %s", devname, strerror(errno));
}
desired_freq = this->spec.freq;
/* Determine the audio parameters from the AudioSpec */
switch (SDL_AUDIO_BITSIZE(this->spec.format)) {
case 8:
{ /* Unsigned 8 bit audio data */
this->spec.format = AUDIO_U8;
#ifdef AUDIO_SETINFO
enc = AUDIO_ENCODING_LINEAR8;
#endif
}
break;
case 16:
{ /* Signed 16 bit audio data */
this->spec.format = AUDIO_S16SYS;
#ifdef AUDIO_SETINFO
enc = AUDIO_ENCODING_LINEAR;
#endif
}
break;
default:
{
/* !!! FIXME: fallback to conversion on unsupported types! */
return SDL_SetError("Unsupported audio format");
}
}
this->hidden->audio_fmt = this->spec.format;
this->hidden->ulaw_only = 0; /* modern Suns do support linear audio */
#ifdef AUDIO_SETINFO
for (;;) {
audio_info_t info;
AUDIO_INITINFO(&info); /* init all fields to "no change" */
/* Try to set the requested settings */
info.play.sample_rate = this->spec.freq;
info.play.channels = this->spec.channels;
info.play.precision = (enc == AUDIO_ENCODING_ULAW)
? 8 : this->spec.format & 0xff;
info.play.encoding = enc;
if (ioctl(this->hidden->audio_fd, AUDIO_SETINFO, &info) == 0) {
/* Check to be sure we got what we wanted */
if (ioctl(this->hidden->audio_fd, AUDIO_GETINFO, &info) < 0) {
return SDL_SetError("Error getting audio parameters: %s",
strerror(errno));
}
if (info.play.encoding == enc
&& info.play.precision == (this->spec.format & 0xff)
&& info.play.channels == this->spec.channels) {
/* Yow! All seems to be well! */
this->spec.freq = info.play.sample_rate;
break;
}
}
switch (enc) {
case AUDIO_ENCODING_LINEAR8:
/* unsigned 8bit apparently not supported here */
enc = AUDIO_ENCODING_LINEAR;
this->spec.format = AUDIO_S16SYS;
break; /* try again */
case AUDIO_ENCODING_LINEAR:
/* linear 16bit didn't work either, resort to µ-law */
enc = AUDIO_ENCODING_ULAW;
this->spec.channels = 1;
this->spec.freq = 8000;
this->spec.format = AUDIO_U8;
this->hidden->ulaw_only = 1;
break;
default:
/* oh well... */
return SDL_SetError("Error setting audio parameters: %s",
strerror(errno));
}
}
#endif /* AUDIO_SETINFO */
this->hidden->written = 0;
/* We can actually convert on-the-fly to U-Law */
if (this->hidden->ulaw_only) {
this->spec.freq = desired_freq;
this->hidden->fragsize = (this->spec.samples * 1000) /
(this->spec.freq / 8);
this->hidden->frequency = 8;
this->hidden->ulaw_buf = (Uint8 *) SDL_malloc(this->hidden->fragsize);
if (this->hidden->ulaw_buf == NULL) {
return SDL_OutOfMemory();
}
this->spec.channels = 1;
} else {
this->hidden->fragsize = this->spec.samples;
this->hidden->frequency = this->spec.freq / 1000;
}
#ifdef DEBUG_AUDIO
fprintf(stderr, "Audio device %s U-Law only\n",
this->hidden->ulaw_only ? "is" : "is not");
fprintf(stderr, "format=0x%x chan=%d freq=%d\n",
this->spec.format, this->spec.channels, this->spec.freq);
#endif
/* Update the fragment size as size in bytes */
SDL_CalculateAudioSpec(&this->spec);
/* Allocate mixing buffer */
this->hidden->mixbuf = (Uint8 *) SDL_malloc(this->spec.size);
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;
}
/************************************************************************/
/* This function (snd2au()) copyrighted: */
/************************************************************************/
/* Copyright 1989 by Rich Gopstein and Harris Corporation */
/* */
/* Permission to use, copy, modify, and distribute this software */
/* and its documentation for any purpose and without fee is */
/* hereby granted, provided that the above copyright notice */
/* appears in all copies and that both that copyright notice and */
/* this permission notice appear in supporting documentation, and */
/* that the name of Rich Gopstein and Harris Corporation not be */
/* used in advertising or publicity pertaining to distribution */
/* of the software without specific, written prior permission. */
/* Rich Gopstein and Harris Corporation make no representations */
/* about the suitability of this software for any purpose. It */
/* provided "as is" without express or implied warranty. */
/************************************************************************/
static Uint8
snd2au(int sample)
{
int mask;
if (sample < 0) {
sample = -sample;
mask = 0x7f;
} else {
mask = 0xff;
}
if (sample < 32) {
sample = 0xF0 | (15 - sample / 2);
} else if (sample < 96) {
sample = 0xE0 | (15 - (sample - 32) / 4);
} else if (sample < 224) {
sample = 0xD0 | (15 - (sample - 96) / 8);
} else if (sample < 480) {
sample = 0xC0 | (15 - (sample - 224) / 16);
} else if (sample < 992) {
sample = 0xB0 | (15 - (sample - 480) / 32);
} else if (sample < 2016) {
sample = 0xA0 | (15 - (sample - 992) / 64);
} else if (sample < 4064) {
sample = 0x90 | (15 - (sample - 2016) / 128);
} else if (sample < 8160) {
sample = 0x80 | (15 - (sample - 4064) / 256);
} else {
sample = 0x80;
}
return (mask & sample);
}
static int
SUNAUDIO_Init(SDL_AudioDriverImpl * impl)
{
/* Set the function pointers */
impl->DetectDevices = SUNAUDIO_DetectDevices;
impl->OpenDevice = SUNAUDIO_OpenDevice;
impl->PlayDevice = SUNAUDIO_PlayDevice;
impl->WaitDevice = SUNAUDIO_WaitDevice;
impl->GetDeviceBuf = SUNAUDIO_GetDeviceBuf;
impl->CloseDevice = SUNAUDIO_CloseDevice;
impl->AllowsArbitraryDeviceNames = 1;
return 1; /* this audio target is available. */
}
AudioBootStrap SUNAUDIO_bootstrap = {
"audio", "UNIX /dev/audio interface", SUNAUDIO_Init, 0
};
#endif /* SDL_AUDIO_DRIVER_SUNAUDIO */
/* vi: set ts=4 sw=4 expandtab: */
OPEN_FLAGS_INPUT
#define OPEN_FLAGS_INPUT
Definition: SDL_audiodev_c.h:33
SDL_TRUE
Definition: SDL_stdinc.h:142
SDL_IOReady
int SDL_IOReady(int fd, SDL_bool forWrite, int timeoutMS)
Definition: SDL_poll.c:38
SDL_AudioDriverImpl::DetectDevices
void(* DetectDevices)(void)
Definition: SDL_sysaudio.h:67
SDL_AudioDriverImpl::PlayDevice
void(* PlayDevice)(_THIS)
Definition: SDL_sysaudio.h:73
SDL_AudioSpec::samples
Uint16 samples
Definition: SDL_audio.h:183
SDL_AudioDriverImpl::WaitDevice
void(* WaitDevice)(_THIS)
Definition: SDL_sysaudio.h:72
SDL_OpenedAudioDeviceDisconnected
void SDL_OpenedAudioDeviceDisconnected(SDL_AudioDevice *device)
Definition: SDL_audio.c:449
SDL_AudioFormat
Uint16 SDL_AudioFormat
Audio format flags.
Definition: SDL_audio.h:64
AUDIO_S16SYS
#define AUDIO_S16SYS
Definition: SDL_audio.h:123
SDL_zerop
#define SDL_zerop(x)
Definition: SDL_stdinc.h:417
SDL_PrivateAudioData
Definition: SDL_alsa_audio.h:33
SUNAUDIO_bootstrap
AudioBootStrap SUNAUDIO_bootstrap
format
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1572
spec
SDL_AudioSpec spec
Definition: loopwave.c:31
SDL_GetAudioDeviceName
#define SDL_GetAudioDeviceName
Definition: SDL_dynapi_overrides.h:80
AUDIO_U8
#define AUDIO_U8
Definition: SDL_audio.h:89
SDL_EnumUnixAudioDevices
void SDL_EnumUnixAudioDevices(const int classic, int(*test)(int))
AudioBootStrap
Definition: SDL_sysaudio.h:175
SDL_AudioSpec::freq
int freq
Definition: SDL_audio.h:179
handle
EGLImageKHR EGLint EGLint * handle
Definition: eglext.h:937
SDL_sunaudio.h
SDL_AudioSpec::channels
Uint8 channels
Definition: SDL_audio.h:181
OPEN_FLAGS_OUTPUT
#define OPEN_FLAGS_OUTPUT
Definition: SDL_audiodev_c.h:32
_THIS
#define _THIS
Definition: SDL_alsa_audio.h:31
Uint8
uint8_t Uint8
Definition: SDL_stdinc.h:157
SDL_free
#define SDL_free
Definition: SDL_dynapi_overrides.h:377
SDL_AUDIO_BITSIZE
#define SDL_AUDIO_BITSIZE(x)
Definition: SDL_audio.h:75
SDL_AudioDriverImpl
Definition: SDL_sysaudio.h:65
mask
GLenum GLint GLuint mask
Definition: SDL_opengl_glext.h:657
SDL_CalculateAudioSpec
void SDL_CalculateAudioSpec(SDL_AudioSpec *spec)
Definition: SDL_audio.c:1605
Sint32
int32_t Sint32
Definition: SDL_stdinc.h:175
SDL_Delay
#define SDL_Delay
Definition: SDL_dynapi_overrides.h:486
SDL_AudioSpec::size
Uint32 size
Definition: SDL_audio.h:185
SDL_AudioDriverImpl::OpenDevice
int(* OpenDevice)(_THIS, void *handle, const char *devname, int iscapture)
Definition: SDL_sysaudio.h:68
NULL
#define NULL
Definition: begin_code.h:164
SDL_OutOfMemory
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
SDL_SetError
#define SDL_SetError
Definition: SDL_dynapi_overrides.h:30
flags
GLbitfield flags
Definition: SDL_opengl_glext.h:1480
SDL_AudioDriverImpl::CloseDevice
void(* CloseDevice)(_THIS)
Definition: SDL_sysaudio.h:79
SDL_AudioDriverImpl::AllowsArbitraryDeviceNames
int AllowsArbitraryDeviceNames
Definition: SDL_sysaudio.h:94
SDL_audio.h
SDL_AudioSpec::format
SDL_AudioFormat format
Definition: SDL_audio.h:180
SDL_AudioDriverImpl::GetDeviceBuf
Uint8 *(* GetDeviceBuf)(_THIS)
Definition: SDL_sysaudio.h:75
SDL_malloc
#define SDL_malloc
Definition: SDL_dynapi_overrides.h:374
SDL_timer.h
SDL_memset
#define SDL_memset
Definition: SDL_dynapi_overrides.h:386
Sint16
int16_t Sint16
Definition: SDL_stdinc.h:163
left
GLint left
Definition: SDL_opengl_glext.h:1949