Mercurial > sdl-ios-xcode
view src/audio/dmedia/SDL_irixaudio.c @ 2866:e532417a6977
Fixed SDL 1.2 compatibility problem.
The API specifies that SDL_OpenAudio() will fill out the 'desired' audio spec
with the correct samples and size set by the driver. This value is important
since it may be used by applications that size audio buffers, etc.
However, we want to allow advanced applications to call SDL_OpenAudioDevice()
which gets passed a const 'desired' parameter, and have the correct data filled
into the 'obtained' parameter, possibly allowing or not allowing format changes.
So... 'obtained' becomes the audio format the user callback is expected to use,
and we add flags to allow the application to specify which format changes are
allowed.
Note: We really need to add a way to query the 'obtained' audio spec.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 13 Dec 2008 06:36:47 +0000 |
parents | 99210400e8b9 |
children | f7b03b6838cb |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2009 Sam Lantinga 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 Sam Lantinga slouken@libsdl.org */ #include <errno.h> #include "SDL_config.h" /* Allow access to a raw mixing buffer (For IRIX 6.5 and higher) */ /* patch for IRIX 5 by Georg Schwarz 18/07/2004 */ #include "SDL_timer.h" #include "SDL_audio.h" #include "../SDL_audiomem.h" #include "../SDL_audio_c.h" #include "SDL_irixaudio.h" #ifndef AL_RESOURCE /* as a test whether we use the old IRIX audio libraries */ #define OLD_IRIX_AUDIO #define alClosePort(x) ALcloseport(x) #define alFreeConfig(x) ALfreeconfig(x) #define alGetFillable(x) ALgetfillable(x) #define alNewConfig() ALnewconfig() #define alOpenPort(x,y,z) ALopenport(x,y,z) #define alSetChannels(x,y) ALsetchannels(x,y) #define alSetQueueSize(x,y) ALsetqueuesize(x,y) #define alSetSampFmt(x,y) ALsetsampfmt(x,y) #define alSetWidth(x,y) ALsetwidth(x,y) #endif void static IRIXAUDIO_WaitDevice(_THIS) { Sint32 timeleft; timeleft = this->spec.samples - alGetFillable(this->hidden->audio_port); if (timeleft > 0) { timeleft /= (this->spec.freq / 1000); SDL_Delay((Uint32) timeleft); } } static void IRIXAUDIO_PlayDevice(_THIS) { /* Write the audio data out */ ALport port = this->hidden->audio_port; Uint8 *mixbuf = this->hidden->mixbuf; if (alWriteFrames(port, mixbuf, this->spec.samples) < 0) { /* Assume fatal error, for now */ this->enabled = 0; } } static Uint8 * IRIXAUDIO_GetDeviceBuf(_THIS) { return (this->hidden->mixbuf); } static void IRIXAUDIO_CloseDevice(_THIS) { if (this->hidden != NULL) { if (this->hidden->mixbuf != NULL) { SDL_FreeAudioMem(this->hidden->mixbuf); this->hidden->mixbuf = NULL; } if (this->hidden->audio_port != NULL) { alClosePort(this->hidden->audio_port); this->hidden->audio_port = NULL; } SDL_free(this->hidden); this->hidden = NULL; } } static int IRIXAUDIO_OpenDevice(_THIS, const char *devname, int iscapture) { SDL_AudioFormat test_format = SDL_FirstAudioFormat(this->spec.format); long width = 0; long fmt = 0; int valid = 0; /* !!! FIXME: Handle multiple devices and capture? */ /* Initialize all variables that we clean on shutdown */ this->hidden = (struct SDL_PrivateAudioData *) SDL_malloc((sizeof *this->hidden)); if (this->hidden == NULL) { SDL_OutOfMemory(); return 0; } SDL_memset(this->hidden, 0, (sizeof *this->hidden)); #ifdef OLD_IRIX_AUDIO { long audio_param[2]; audio_param[0] = AL_OUTPUT_RATE; audio_param[1] = this->spec.freq; valid = (ALsetparams(AL_DEFAULT_DEVICE, audio_param, 2) < 0); } #else { ALpv audio_param; audio_param.param = AL_RATE; audio_param.value.i = this->spec.freq; valid = (alSetParams(AL_DEFAULT_OUTPUT, &audio_param, 1) < 0); } #endif while ((!valid) && (test_format)) { valid = 1; this->spec.format = test_format; switch (test_format) { case AUDIO_S8: width = AL_SAMPLE_8; fmt = AL_SAMPFMT_TWOSCOMP; break; case AUDIO_S16SYS: width = AL_SAMPLE_16; fmt = AL_SAMPFMT_TWOSCOMP; break; case AUDIO_F32SYS: width = 0; /* not used here... */ fmt = AL_SAMPFMT_FLOAT; break; /* Docs say there is int24, but not int32.... */ default: valid = 0; test_format = SDL_NextAudioFormat(); break; } if (valid) { ALconfig audio_config = alNewConfig(); valid = 0; if (audio_config) { if (alSetChannels(audio_config, this->spec.channels) < 0) { if (this->spec.channels > 2) { /* can't handle > stereo? */ this->spec.channels = 2; /* try again below. */ } } if ((alSetSampFmt(audio_config, fmt) >= 0) && ((!width) || (alSetWidth(audio_config, width) >= 0)) && (alSetQueueSize(audio_config, this->spec.samples * 2) >= 0) && (alSetChannels(audio_config, this->spec.channels) >= 0)) { this->hidden->audio_port = alOpenPort("SDL audio", "w", audio_config); if (this->hidden->audio_port == NULL) { /* docs say AL_BAD_CHANNELS happens here, too. */ int err = oserror(); if (err == AL_BAD_CHANNELS) { this->spec.channels = 2; alSetChannels(audio_config, this->spec.channels); this->hidden->audio_port = alOpenPort("SDL audio", "w", audio_config); } } if (this->hidden->audio_port != NULL) { valid = 1; } } alFreeConfig(audio_config); } } } if (!valid) { IRIXAUDIO_CloseDevice(this); SDL_SetError("Unsupported audio format"); return 0; } /* Update the fragment size as size in bytes */ SDL_CalculateAudioSpec(&this->spec); /* Allocate mixing buffer */ this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->spec.size); if (this->hidden->mixbuf == NULL) { IRIXAUDIO_CloseDevice(this); SDL_OutOfMemory(); return 0; } SDL_memset(this->hidden->mixbuf, this->spec.silence, this->spec.size); /* We're ready to rock and roll. :-) */ return 1; } static int IRIXAUDIO_Init(SDL_AudioDriverImpl * impl) { /* Set the function pointers */ impl->OpenDevice = DSP_OpenDevice; impl->PlayDevice = DSP_PlayDevice; impl->WaitDevice = DSP_WaitDevice; impl->GetDeviceBuf = DSP_GetDeviceBuf; impl->CloseDevice = DSP_CloseDevice; impl->OnlyHasDefaultOutputDevice = 1; /* !!! FIXME: not true, I think. */ return 1; } AudioBootStrap IRIXAUDIO_bootstrap = { "AL", "IRIX DMedia audio", IRIXAUDIO_Init, 0 }; /* vi: set ts=4 sw=4 expandtab: */