Mercurial > sdl-ios-xcode
diff src/audio/openbsd/SDL_openbsdaudio.c @ 37:3ad7157c6cfa
Added native OpenBSD audio driver (thanks vedge!)
author | Sam Lantinga <slouken@lokigames.com> |
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date | Sat, 26 May 2001 16:58:37 +0000 |
parents | |
children | ae6e6b73333f |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/audio/openbsd/SDL_openbsdaudio.c Sat May 26 16:58:37 2001 +0000 @@ -0,0 +1,408 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997, 1998, 1999, 2000, 2001 Sam Lantinga + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the Free + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + + Sam Lantinga + slouken@devolution.com +*/ + +/* + * Driver for native OpenBSD audio(4). + * vedge@vedge.com.ar. + */ + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <fcntl.h> +#include <signal.h> +#include <sys/time.h> +#include <sys/ioctl.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/audioio.h> + +#include "SDL_audio.h" +#include "SDL_error.h" +#include "SDL_audiomem.h" +#include "SDL_audio_c.h" +#include "SDL_timer.h" +#include "SDL_audiodev_c.h" +#include "SDL_openbsdaudio.h" + +/* The tag name used by OpenBSD audio */ +#define OBSD_DRIVER_NAME "openbsd" + +/* Open the audio device for playback, and don't block if busy */ +/* #define USE_BLOCKING_WRITES */ + +/* Use timer for synchronization */ +/* #define USE_TIMER_SYNC */ + +/* #define DEBUG_AUDIO */ +/* #define DEBUG_AUDIO_STREAM */ + +#ifdef USE_BLOCKING_WRITES +#define OPEN_FLAGS O_WRONLY +#else +#define OPEN_FLAGS (O_WRONLY|O_NONBLOCK) +#endif + +/* Audio driver functions */ +static void OBSD_WaitAudio(_THIS); +static int OBSD_OpenAudio(_THIS, SDL_AudioSpec *spec); +static void OBSD_PlayAudio(_THIS); +static Uint8 *OBSD_GetAudioBuf(_THIS); +static void OBSD_CloseAudio(_THIS); + +#ifdef DEBUG_AUDIO +static void OBSD_Status(_THIS); +#endif + +/* Audio driver bootstrap functions */ + +static int +Audio_Available(void) +{ + int fd; + int available; + + available = 0; + fd = SDL_OpenAudioPath(NULL, 0, OPEN_FLAGS, 0); + if(fd >= 0) { + available = 1; + close(fd); + } + return(available); +} + +static void +Audio_DeleteDevice(SDL_AudioDevice *device) +{ + free(device->hidden); + free(device); +} + +static SDL_AudioDevice +*Audio_CreateDevice(int devindex) +{ + SDL_AudioDevice *this; + + /* Initialize all variables that we clean on shutdown */ + this = (SDL_AudioDevice*)malloc(sizeof(SDL_AudioDevice)); + if(this) { + memset(this, 0, (sizeof *this)); + this->hidden = + (struct SDL_PrivateAudioData*)malloc((sizeof *this->hidden)); + } + if((this == NULL) || (this->hidden == NULL)) { + SDL_OutOfMemory(); + if(this) free(this); + return(0); + } + memset(this->hidden, 0, (sizeof *this->hidden)); + audio_fd = -1; + + /* Set the function pointers */ + this->OpenAudio = OBSD_OpenAudio; + this->WaitAudio = OBSD_WaitAudio; + this->PlayAudio = OBSD_PlayAudio; + this->GetAudioBuf = OBSD_GetAudioBuf; + this->CloseAudio = OBSD_CloseAudio; + + this->free = Audio_DeleteDevice; + + return this; +} + +AudioBootStrap OBSD_bootstrap = { + OBSD_DRIVER_NAME, "Native OpenBSD audio", + Audio_Available, Audio_CreateDevice +}; + +/* This function waits until it is possible to write a full sound buffer */ +static void +OBSD_WaitAudio(_THIS) +{ +#ifndef USE_BLOCKING_WRITES + fd_set fdset; + + /* Check to see if the thread-parent process is still alive */ + { + static int cnt = 0; + /* Note that this only works with thread implementations + 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; + } + } + +#ifdef USE_TIMER_SYNC + /* See if we need to use timed audio synchronization */ + if(frame_ticks) + { + /* Use timer for general audio synchronization */ + Sint32 ticks; + + ticks = ((Sint32)(next_frame - SDL_GetTicks())) - FUDGE_TICKS; + if(ticks > 0) + SDL_Delay(ticks); + } + else +#endif /* USE_TIMER_SYNC */ + { + /* Use select() for audio synchronization */ + struct timeval timeout; + FD_ZERO(&fdset); + FD_SET(audio_fd, &fdset); + timeout.tv_sec = 10; + timeout.tv_usec = 0; + +#if defined(DEBUG_AUDIO_STREAM) && defined(DEBUG_AUDIO_STREAM) + OBSD_Status(this); +#endif + if(select(audio_fd+1, NULL, &fdset, NULL, &timeout) <= 0) + { + const char *message = + "Audio timeout - buggy audio driver? (disabled)"; + fprintf(stderr, "SDL: %s\n", message); + this->enabled = 0; + audio_fd = -1; + } + } +#endif /* !USE_BLOCKING_WRITES */ + +} + +static void +OBSD_PlayAudio(_THIS) +{ + int written; + + /* Write the audio data, checking for EAGAIN on broken audio drivers */ + do + { + written = write(audio_fd, mixbuf, mixlen); + if((written < 0) && ((errno == 0) || (errno == EAGAIN))) + SDL_Delay(1); + } + while((written < 0) && + ((errno == 0) || (errno == EAGAIN) || (errno == EINTR))); + +#ifdef USE_TIMER_SYNC + if(frame_ticks) + next_frame += frame_ticks; +#endif + + /* If we couldn't write, assume fatal error for now */ + if(written < 0) + this->enabled = 0; + +#ifdef DEBUG_AUDIO_STREAM + fprintf(stderr, "Wrote %d bytes of audio data\n", written); +#endif +} + +static Uint8 +*OBSD_GetAudioBuf(_THIS) +{ + return(mixbuf); +} + +static void +OBSD_CloseAudio(_THIS) +{ + if(mixbuf != NULL) { + SDL_FreeAudioMem(mixbuf); + mixbuf = NULL; + } + if(audio_fd >= 0) { + close(audio_fd); + audio_fd = -1; + } +} + +#ifdef DEBUG_AUDIO +void +OBSD_Status(_THIS) +{ + audio_info_t info; + + if(ioctl(audio_fd, AUDIO_GETINFO, &info) < 0) { + fprintf(stderr,"AUDIO_GETINFO failed.\n"); + return; + } + + fprintf(stderr," +[play/record info] +buffer size : %d bytes +sample rate : %i Hz +channels : %i +precision : %i-bit +encoding : 0x%x +seek : %i +sample count : %i +EOF count : %i +paused : %s +error occured : %s +waiting : %s +active : %s +", + info.play.buffer_size, + info.play.sample_rate, + info.play.channels, + info.play.precision, + info.play.encoding, + info.play.seek, + info.play.samples, + info.play.eof, + info.play.pause ? "yes" : "no", + info.play.error ? "yes" : "no", + info.play.waiting ? "yes" : "no", + info.play.active ? "yes": "no"); + + fprintf(stderr," +[audio info] +monitor_gain : %i +hw block size : %d bytes +hi watermark : %i +lo watermark : %i +audio mode : %s +", + info.monitor_gain, + info.blocksize, + info.hiwat, info.lowat, + (info.mode == AUMODE_PLAY) ? "PLAY" + : (info.mode = AUMODE_RECORD) ? "RECORD" + : (info.mode == AUMODE_PLAY_ALL ? "PLAY_ALL" + : "???")); +} +#endif /* DEBUG_AUDIO */ + +static int +OBSD_OpenAudio(_THIS, SDL_AudioSpec *spec) +{ + char audiodev[64]; + Uint16 setenc; + audio_encoding_t enc; + audio_info_t info; + + AUDIO_INITINFO(&info); + + /* Calculate the final parameters for this audio specification */ + SDL_CalculateAudioSpec(spec); + +#ifdef USE_TIMER_SYNC + frame_ticks = 0.0; +#endif + + /* Open the audio device */ + audio_fd = SDL_OpenAudioPath(audiodev, sizeof(audiodev), OPEN_FLAGS, 0); + if(audio_fd < 0) { + SDL_SetError("Couldn't open %s: %s", audiodev, strerror(errno)); + return(-1); + } + + /* Set to play mode */ + info.mode = AUMODE_PLAY; + if(ioctl(audio_fd, AUDIO_SETINFO, &info) < 0) { + SDL_SetError("Couldn't put device into play mode"); + return(-1); + } + + mixbuf = NULL; + setenc = 0; + + for(enc.index = 0; (ioctl(audio_fd, AUDIO_GETENC, &enc)>=0) + && (enc.encoding != setenc); enc.index++) + { + switch(spec->format) + { + case AUDIO_U8: /* 8-bit unsigned linear */ + setenc = AUDIO_ENCODING_PCM8; + break; + case AUDIO_S8: /* 8-bit signed linear */ + setenc = AUDIO_ENCODING_SLINEAR; + break; + case AUDIO_U16LSB: /* 16-bit unsigned linear, LSB */ + setenc = AUDIO_ENCODING_ULINEAR_LE; + break; + case AUDIO_U16MSB: /* 16-bit unsigned linear, MSB */ + setenc = AUDIO_ENCODING_ULINEAR_BE; + break; + case AUDIO_S16LSB: /* 16-bit signed linear, LSB */ + setenc = AUDIO_ENCODING_SLINEAR_LE; + break; + case AUDIO_S16MSB: /* 16-bit signed linear, MSB */ + setenc = AUDIO_ENCODING_SLINEAR_BE; + break; + } +#ifdef DEBUG_AUDIO + fprintf(stderr,"encoding #%i: \"%s\" %i-bit (0x%x) flags=%i...\n", + enc.index, enc.name, enc.precision, enc.encoding, enc.flags); +#endif + } + + if(!setenc) { + SDL_SetError("No supported encoding for 0x%x", spec->format); + return(-1); + } + + /* Set audio encoding */ + info.play.encoding = enc.encoding; + info.play.precision = enc.precision; + if((ioctl(audio_fd, AUDIO_SETINFO, &info) < 0)) { + SDL_SetError("Couldn't set encoding to 0x%x %i-bit", + enc.encoding, enc.precision); + return(-1); + } + + /* Set audio channels */ + info.play.channels = spec->channels; + if(ioctl(audio_fd, AUDIO_SETINFO, &info) < 0) { + info.play.channels = (spec->channels > 1); + ioctl(audio_fd, AUDIO_SETINFO, &info); + } + + /* Set the sample rate */ + info.play.sample_rate = spec->freq; + if(ioctl(audio_fd, AUDIO_SETINFO, &info) < 0) { + SDL_SetError("Couldn't set sample rate to %i Hz", spec->freq); + return(-1); + } + + /* Allocate mixing buffer */ + mixlen = spec->size; + mixbuf = (Uint8*)SDL_AllocAudioMem(mixlen); + if(mixbuf == NULL) { + return(-1); + } + memset(mixbuf, spec->silence, spec->size); + + /* Get the parent process id (we're the parent of the audio thread) */ + parent = getpid(); + +#ifdef DEBUG_AUDIO + OBSD_Status(this); +#endif + + /* We're ready to rock and roll. :-) */ + return(0); +}