Mercurial > sdl-ios-xcode
view src/audio/arts/SDL_artsaudio.c @ 1516:4d241ea8a1cd
Updated MacOS Classic build
author | Sam Lantinga <slouken@libsdl.org> |
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date | Mon, 13 Mar 2006 05:36:42 +0000 |
parents | d910939febfa |
children | 782fd950bd46 c121d94672cb 33c248ea75f9 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2006 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 "SDL_config.h" /* Allow access to a raw mixing buffer */ #include "SDL_timer.h" #include "SDL_audio.h" #include "../SDL_audiomem.h" #include "../SDL_audio_c.h" #include "../SDL_audiodev_c.h" #include "SDL_artsaudio.h" #ifdef SDL_AUDIO_DRIVER_ARTS_DYNAMIC #include "SDL_name.h" #include "SDL_loadso.h" #else #define SDL_NAME(X) X #endif /* The tag name used by artsc audio */ #define ARTS_DRIVER_NAME "arts" /* Audio driver functions */ static int ARTS_OpenAudio(_THIS, SDL_AudioSpec *spec); static void ARTS_WaitAudio(_THIS); static void ARTS_PlayAudio(_THIS); static Uint8 *ARTS_GetAudioBuf(_THIS); static void ARTS_CloseAudio(_THIS); #ifdef SDL_AUDIO_DRIVER_ARTS_DYNAMIC static const char *arts_library = SDL_AUDIO_DRIVER_ARTS_DYNAMIC; static void *arts_handle = NULL; static int arts_loaded = 0; static int (*SDL_NAME(arts_init))(void); static void (*SDL_NAME(arts_free))(void); static arts_stream_t (*SDL_NAME(arts_play_stream))(int rate, int bits, int channels, const char *name); static int (*SDL_NAME(arts_stream_set))(arts_stream_t s, arts_parameter_t param, int value); static int (*SDL_NAME(arts_stream_get))(arts_stream_t s, arts_parameter_t param); static int (*SDL_NAME(arts_write))(arts_stream_t s, const void *buffer, int count); static void (*SDL_NAME(arts_close_stream))(arts_stream_t s); static struct { const char *name; void **func; } arts_functions[] = { { "arts_init", (void **)&SDL_NAME(arts_init) }, { "arts_free", (void **)&SDL_NAME(arts_free) }, { "arts_play_stream", (void **)&SDL_NAME(arts_play_stream) }, { "arts_stream_set", (void **)&SDL_NAME(arts_stream_set) }, { "arts_stream_get", (void **)&SDL_NAME(arts_stream_get) }, { "arts_write", (void **)&SDL_NAME(arts_write) }, { "arts_close_stream", (void **)&SDL_NAME(arts_close_stream) }, }; static void UnloadARTSLibrary() { if ( arts_loaded ) { SDL_UnloadObject(arts_handle); arts_handle = NULL; arts_loaded = 0; } } static int LoadARTSLibrary(void) { int i, retval = -1; arts_handle = SDL_LoadObject(arts_library); if ( arts_handle ) { arts_loaded = 1; retval = 0; for ( i=0; i<SDL_arraysize(arts_functions); ++i ) { *arts_functions[i].func = SDL_LoadFunction(arts_handle, arts_functions[i].name); if ( !*arts_functions[i].func ) { retval = -1; UnloadARTSLibrary(); break; } } } return retval; } #else static void UnloadARTSLibrary() { return; } static int LoadARTSLibrary(void) { return 0; } #endif /* SDL_AUDIO_DRIVER_ARTS_DYNAMIC */ /* Audio driver bootstrap functions */ static int Audio_Available(void) { int available = 0; if ( LoadARTSLibrary() < 0 ) { return available; } if ( SDL_NAME(arts_init)() == 0 ) { #define ARTS_CRASH_HACK /* Play a stream so aRts doesn't crash */ #ifdef ARTS_CRASH_HACK arts_stream_t stream2; stream2=SDL_NAME(arts_play_stream)(44100, 16, 2, "SDL"); SDL_NAME(arts_write)(stream2, "", 0); SDL_NAME(arts_close_stream)(stream2); #endif available = 1; SDL_NAME(arts_free)(); } UnloadARTSLibrary(); return available; } static void Audio_DeleteDevice(SDL_AudioDevice *device) { SDL_free(device->hidden); SDL_free(device); UnloadARTSLibrary(); } static SDL_AudioDevice *Audio_CreateDevice(int devindex) { SDL_AudioDevice *this; /* Initialize all variables that we clean on shutdown */ LoadARTSLibrary(); this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice)); if ( this ) { SDL_memset(this, 0, (sizeof *this)); this->hidden = (struct SDL_PrivateAudioData *) SDL_malloc((sizeof *this->hidden)); } if ( (this == NULL) || (this->hidden == NULL) ) { SDL_OutOfMemory(); if ( this ) { SDL_free(this); } return(0); } SDL_memset(this->hidden, 0, (sizeof *this->hidden)); stream = 0; /* Set the function pointers */ this->OpenAudio = ARTS_OpenAudio; this->WaitAudio = ARTS_WaitAudio; this->PlayAudio = ARTS_PlayAudio; this->GetAudioBuf = ARTS_GetAudioBuf; this->CloseAudio = ARTS_CloseAudio; this->free = Audio_DeleteDevice; return this; } AudioBootStrap ARTS_bootstrap = { ARTS_DRIVER_NAME, "Analog Realtime Synthesizer", Audio_Available, Audio_CreateDevice }; /* This function waits until it is possible to write a full sound buffer */ static void ARTS_WaitAudio(_THIS) { Sint32 ticks; /* 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; } } } /* Use timer for general audio synchronization */ ticks = ((Sint32)(next_frame - SDL_GetTicks()))-FUDGE_TICKS; if ( ticks > 0 ) { SDL_Delay(ticks); } } static void ARTS_PlayAudio(_THIS) { int written; /* Write the audio data */ written = SDL_NAME(arts_write)(stream, mixbuf, mixlen); /* If timer synchronization is enabled, set the next write frame */ if ( frame_ticks ) { next_frame += frame_ticks; } /* If we couldn't write, assume fatal error for now */ if ( written < 0 ) { this->enabled = 0; } #ifdef DEBUG_AUDIO fprintf(stderr, "Wrote %d bytes of audio data\n", written); #endif } static Uint8 *ARTS_GetAudioBuf(_THIS) { return(mixbuf); } static void ARTS_CloseAudio(_THIS) { if ( mixbuf != NULL ) { SDL_FreeAudioMem(mixbuf); mixbuf = NULL; } if ( stream ) { SDL_NAME(arts_close_stream)(stream); stream = 0; } SDL_NAME(arts_free)(); } static int ARTS_OpenAudio(_THIS, SDL_AudioSpec *spec) { int bits, frag_spec; Uint16 test_format, format; /* Reset the timer synchronization flag */ frame_ticks = 0.0; mixbuf = NULL; /* Try for a closest match on audio format */ format = 0; bits = 0; for ( test_format = SDL_FirstAudioFormat(spec->format); ! format && test_format; ) { #ifdef DEBUG_AUDIO fprintf(stderr, "Trying format 0x%4.4x\n", test_format); #endif switch ( test_format ) { case AUDIO_U8: bits = 8; format = 1; break; case AUDIO_S16LSB: bits = 16; format = 1; break; default: format = 0; break; } if ( ! format ) { test_format = SDL_NextAudioFormat(); } } if ( format == 0 ) { SDL_SetError("Couldn't find any hardware audio formats"); return(-1); } spec->format = test_format; if ( SDL_NAME(arts_init)() != 0 ) { SDL_SetError("Unable to initialize ARTS"); return(-1); } stream = SDL_NAME(arts_play_stream)(spec->freq, bits, spec->channels, "SDL"); /* Calculate the final parameters for this audio specification */ SDL_CalculateAudioSpec(spec); /* Determine the power of two of the fragment size */ for ( frag_spec = 0; (0x01<<frag_spec) < spec->size; ++frag_spec ); if ( (0x01<<frag_spec) != spec->size ) { SDL_SetError("Fragment size must be a power of two"); return(-1); } frag_spec |= 0x00020000; /* two fragments, for low latency */ #ifdef ARTS_P_PACKET_SETTINGS SDL_NAME(arts_stream_set)(stream, ARTS_P_PACKET_SETTINGS, frag_spec); #else SDL_NAME(arts_stream_set)(stream, ARTS_P_PACKET_SIZE, frag_spec&0xffff); SDL_NAME(arts_stream_set)(stream, ARTS_P_PACKET_COUNT, frag_spec>>16); #endif spec->size = SDL_NAME(arts_stream_get)(stream, ARTS_P_PACKET_SIZE); /* Allocate mixing buffer */ mixlen = spec->size; mixbuf = (Uint8 *)SDL_AllocAudioMem(mixlen); if ( mixbuf == NULL ) { return(-1); } SDL_memset(mixbuf, spec->silence, spec->size); /* Get the parent process id (we're the parent of the audio thread) */ parent = getpid(); /* We're ready to rock and roll. :-) */ return(0); }