Mercurial > sdl-ios-xcode
diff src/audio/dma/SDL_dmaaudio.c @ 1895:c121d94672cb
SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 10 Jul 2006 21:04:37 +0000 |
parents | d910939febfa |
children | 3b4ce57c6215 |
line wrap: on
line diff
--- a/src/audio/dma/SDL_dmaaudio.c Thu Jul 06 18:01:37 2006 +0000 +++ b/src/audio/dma/SDL_dmaaudio.c Mon Jul 10 21:04:37 2006 +0000 @@ -24,7 +24,7 @@ /* Allow access to a raw mixing buffer */ #include <stdio.h> -#include <string.h> /* For strerror() */ +#include <string.h> /* For strerror() */ #include <errno.h> #include <unistd.h> #include <fcntl.h> @@ -60,7 +60,7 @@ #define OPEN_FLAGS (O_RDWR|O_NONBLOCK) /* Audio driver functions */ -static int DMA_OpenAudio(_THIS, SDL_AudioSpec *spec); +static int DMA_OpenAudio(_THIS, SDL_AudioSpec * spec); static void DMA_WaitAudio(_THIS); static void DMA_PlayAudio(_THIS); static Uint8 *DMA_GetAudioBuf(_THIS); @@ -68,388 +68,400 @@ /* Audio driver bootstrap functions */ -static int Audio_Available(void) +static int +Audio_Available(void) { - int available; - int fd; + int available; + int fd; - available = 0; + available = 0; - fd = SDL_OpenAudioPath(NULL, 0, OPEN_FLAGS, 0); - if ( fd >= 0 ) { - int caps; - struct audio_buf_info info; + fd = SDL_OpenAudioPath(NULL, 0, OPEN_FLAGS, 0); + if (fd >= 0) { + int caps; + struct audio_buf_info info; - if ( (ioctl(fd, SNDCTL_DSP_GETCAPS, &caps) == 0) && - (caps & DSP_CAP_TRIGGER) && (caps & DSP_CAP_MMAP) && - (ioctl(fd, SNDCTL_DSP_GETOSPACE, &info) == 0) ) { - available = 1; - } - close(fd); - } - return(available); + if ((ioctl(fd, SNDCTL_DSP_GETCAPS, &caps) == 0) && + (caps & DSP_CAP_TRIGGER) && (caps & DSP_CAP_MMAP) && + (ioctl(fd, SNDCTL_DSP_GETOSPACE, &info) == 0)) { + available = 1; + } + close(fd); + } + return (available); } -static void Audio_DeleteDevice(SDL_AudioDevice *device) +static void +Audio_DeleteDevice(SDL_AudioDevice * device) { - SDL_free(device->hidden); - SDL_free(device); + SDL_free(device->hidden); + SDL_free(device); } -static SDL_AudioDevice *Audio_CreateDevice(int devindex) +static SDL_AudioDevice * +Audio_CreateDevice(int devindex) { - SDL_AudioDevice *this; + SDL_AudioDevice *this; - /* Initialize all variables that we clean on shutdown */ - 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)); - audio_fd = -1; + /* Initialize all variables that we clean on shutdown */ + 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)); + audio_fd = -1; - /* Set the function pointers */ - this->OpenAudio = DMA_OpenAudio; - this->WaitAudio = DMA_WaitAudio; - this->PlayAudio = DMA_PlayAudio; - this->GetAudioBuf = DMA_GetAudioBuf; - this->CloseAudio = DMA_CloseAudio; + /* Set the function pointers */ + this->OpenAudio = DMA_OpenAudio; + this->WaitAudio = DMA_WaitAudio; + this->PlayAudio = DMA_PlayAudio; + this->GetAudioBuf = DMA_GetAudioBuf; + this->CloseAudio = DMA_CloseAudio; - this->free = Audio_DeleteDevice; + this->free = Audio_DeleteDevice; - return this; + return this; } AudioBootStrap DMA_bootstrap = { - DMA_DRIVER_NAME, "OSS /dev/dsp DMA audio", - Audio_Available, Audio_CreateDevice + DMA_DRIVER_NAME, "OSS /dev/dsp DMA audio", + Audio_Available, Audio_CreateDevice }; /* This function waits until it is possible to write a full sound buffer */ -static void DMA_WaitAudio(_THIS) +static void +DMA_WaitAudio(_THIS) { - fd_set fdset; + 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; - } - } - } + /* 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; + } + } + } - /* See if we need to use timed audio synchronization */ - if ( frame_ticks ) { - /* Use timer for general audio synchronization */ - Sint32 ticks; + /* 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 { - /* Use select() for audio synchronization */ - struct timeval timeout; - FD_ZERO(&fdset); - FD_SET(audio_fd, &fdset); - timeout.tv_sec = 10; - timeout.tv_usec = 0; + ticks = ((Sint32) (next_frame - SDL_GetTicks())) - FUDGE_TICKS; + if (ticks > 0) { + SDL_Delay(ticks); + } + } else { + /* Use select() for audio synchronization */ + struct timeval timeout; + FD_ZERO(&fdset); + FD_SET(audio_fd, &fdset); + timeout.tv_sec = 10; + timeout.tv_usec = 0; #ifdef DEBUG_AUDIO - fprintf(stderr, "Waiting for audio to get ready\n"); + fprintf(stderr, "Waiting for audio to get ready\n"); #endif - if ( select(audio_fd+1, NULL, &fdset, NULL, &timeout) <= 0 ) { - const char *message = + if (select(audio_fd + 1, NULL, &fdset, NULL, &timeout) <= 0) { + const char *message = #ifdef AUDIO_OSPACE_HACK - "Audio timeout - buggy audio driver? (trying ospace)"; + "Audio timeout - buggy audio driver? (trying ospace)"; #else - "Audio timeout - buggy audio driver? (disabled)"; + "Audio timeout - buggy audio driver? (disabled)"; #endif - /* In general we should never print to the screen, - but in this case we have no other way of letting - the user know what happened. - */ - fprintf(stderr, "SDL: %s\n", message); + /* In general we should never print to the screen, + but in this case we have no other way of letting + the user know what happened. + */ + fprintf(stderr, "SDL: %s\n", message); #ifdef AUDIO_OSPACE_HACK - /* We may be able to use GET_OSPACE trick */ - frame_ticks = (float)(this->spec->samples*1000) / - this->spec->freq; - next_frame = SDL_GetTicks()+frame_ticks; + /* We may be able to use GET_OSPACE trick */ + frame_ticks = (float) (this->spec->samples * 1000) / + this->spec->freq; + next_frame = SDL_GetTicks() + frame_ticks; #else - this->enabled = 0; - /* Don't try to close - may hang */ - audio_fd = -1; + this->enabled = 0; + /* Don't try to close - may hang */ + audio_fd = -1; #ifdef DEBUG_AUDIO - fprintf(stderr, "Done disabling audio\n"); + fprintf(stderr, "Done disabling audio\n"); #endif #endif /* AUDIO_OSPACE_HACK */ - } + } #ifdef DEBUG_AUDIO - fprintf(stderr, "Ready!\n"); + fprintf(stderr, "Ready!\n"); #endif - } + } } -static void DMA_PlayAudio(_THIS) +static void +DMA_PlayAudio(_THIS) { - /* If timer synchronization is enabled, set the next write frame */ - if ( frame_ticks ) { - next_frame += frame_ticks; - } - return; + /* If timer synchronization is enabled, set the next write frame */ + if (frame_ticks) { + next_frame += frame_ticks; + } + return; } -static Uint8 *DMA_GetAudioBuf(_THIS) +static Uint8 * +DMA_GetAudioBuf(_THIS) { - count_info info; - int playing; - int filling; + count_info info; + int playing; + int filling; - /* Get number of blocks, looping if we're not using select() */ - do { - if ( ioctl(audio_fd, SNDCTL_DSP_GETOPTR, &info) < 0 ) { - /* Uh oh... */ - this->enabled = 0; - return(NULL); - } - } while ( frame_ticks && (info.blocks < 1) ); + /* Get number of blocks, looping if we're not using select() */ + do { + if (ioctl(audio_fd, SNDCTL_DSP_GETOPTR, &info) < 0) { + /* Uh oh... */ + this->enabled = 0; + return (NULL); + } + } + while (frame_ticks && (info.blocks < 1)); #ifdef DEBUG_AUDIO - if ( info.blocks > 1 ) { - printf("Warning: audio underflow (%d frags)\n", info.blocks-1); - } + if (info.blocks > 1) { + printf("Warning: audio underflow (%d frags)\n", info.blocks - 1); + } #endif - playing = info.ptr / this->spec.size; - filling = (playing + 1)%num_buffers; - return (dma_buf + (filling * this->spec.size)); + playing = info.ptr / this->spec.size; + filling = (playing + 1) % num_buffers; + return (dma_buf + (filling * this->spec.size)); } -static void DMA_CloseAudio(_THIS) +static void +DMA_CloseAudio(_THIS) { - if ( dma_buf != NULL ) { - munmap(dma_buf, dma_len); - dma_buf = NULL; - } - if ( audio_fd >= 0 ) { - close(audio_fd); - audio_fd = -1; - } + if (dma_buf != NULL) { + munmap(dma_buf, dma_len); + dma_buf = NULL; + } + if (audio_fd >= 0) { + close(audio_fd); + audio_fd = -1; + } } -static int DMA_ReopenAudio(_THIS, const char *audiodev, int format, int stereo, - SDL_AudioSpec *spec) +static int +DMA_ReopenAudio(_THIS, const char *audiodev, int format, int stereo, + SDL_AudioSpec * spec) { - int frag_spec; - int value; + int frag_spec; + int value; - /* Close and then reopen the audio device */ - close(audio_fd); - audio_fd = open(audiodev, O_RDWR, 0); - if ( audio_fd < 0 ) { - SDL_SetError("Couldn't open %s: %s", audiodev, strerror(errno)); - return(-1); - } + /* Close and then reopen the audio device */ + close(audio_fd); + audio_fd = open(audiodev, O_RDWR, 0); + if (audio_fd < 0) { + SDL_SetError("Couldn't open %s: %s", audiodev, strerror(errno)); + return (-1); + } - /* Calculate the final parameters for this audio specification */ - SDL_CalculateAudioSpec(spec); + /* 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); - } + /* 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); + } - /* Set the audio buffering parameters */ - if ( ioctl(audio_fd, SNDCTL_DSP_SETFRAGMENT, &frag_spec) < 0 ) { - SDL_SetError("Couldn't set audio fragment spec"); - return(-1); - } + /* Set the audio buffering parameters */ + if (ioctl(audio_fd, SNDCTL_DSP_SETFRAGMENT, &frag_spec) < 0) { + SDL_SetError("Couldn't set audio fragment spec"); + return (-1); + } - /* Set the audio format */ - value = format; - if ( (ioctl(audio_fd, SNDCTL_DSP_SETFMT, &value) < 0) || - (value != format) ) { - SDL_SetError("Couldn't set audio format"); - return(-1); - } + /* Set the audio format */ + value = format; + if ((ioctl(audio_fd, SNDCTL_DSP_SETFMT, &value) < 0) || (value != format)) { + SDL_SetError("Couldn't set audio format"); + return (-1); + } - /* Set mono or stereo audio */ - value = (spec->channels > 1); - if ( (ioctl(audio_fd, SNDCTL_DSP_STEREO, &stereo) < 0) || - (value != stereo) ) { - SDL_SetError("Couldn't set audio channels"); - return(-1); - } + /* Set mono or stereo audio */ + value = (spec->channels > 1); + if ((ioctl(audio_fd, SNDCTL_DSP_STEREO, &stereo) < 0) || + (value != stereo)) { + SDL_SetError("Couldn't set audio channels"); + return (-1); + } - /* Set the DSP frequency */ - value = spec->freq; - if ( ioctl(audio_fd, SNDCTL_DSP_SPEED, &value) < 0 ) { - SDL_SetError("Couldn't set audio frequency"); - return(-1); - } - spec->freq = value; + /* Set the DSP frequency */ + value = spec->freq; + if (ioctl(audio_fd, SNDCTL_DSP_SPEED, &value) < 0) { + SDL_SetError("Couldn't set audio frequency"); + return (-1); + } + spec->freq = value; - /* We successfully re-opened the audio */ - return(0); + /* We successfully re-opened the audio */ + return (0); } -static int DMA_OpenAudio(_THIS, SDL_AudioSpec *spec) +static int +DMA_OpenAudio(_THIS, SDL_AudioSpec * spec) { - char audiodev[1024]; - int format; - int stereo; - int value; - Uint16 test_format; - struct audio_buf_info info; + char audiodev[1024]; + int format; + int stereo; + int value; + Uint16 test_format; + struct audio_buf_info info; - /* Reset the timer synchronization flag */ - frame_ticks = 0.0; + /* Reset the timer synchronization flag */ + frame_ticks = 0.0; - /* 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); - } - dma_buf = NULL; - ioctl(audio_fd, SNDCTL_DSP_RESET, 0); + /* 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); + } + dma_buf = NULL; + ioctl(audio_fd, SNDCTL_DSP_RESET, 0); - /* Get a list of supported hardware formats */ - if ( ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &value) < 0 ) { - SDL_SetError("Couldn't get audio format list"); - return(-1); - } + /* Get a list of supported hardware formats */ + if (ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &value) < 0) { + SDL_SetError("Couldn't get audio format list"); + return (-1); + } - /* Try for a closest match on audio format */ - format = 0; - for ( test_format = SDL_FirstAudioFormat(spec->format); - ! format && test_format; ) { + /* Try for a closest match on audio format */ + format = 0; + for (test_format = SDL_FirstAudioFormat(spec->format); + !format && test_format;) { #ifdef DEBUG_AUDIO - fprintf(stderr, "Trying format 0x%4.4x\n", test_format); + fprintf(stderr, "Trying format 0x%4.4x\n", test_format); #endif - switch ( test_format ) { - case AUDIO_U8: - if ( value & AFMT_U8 ) { - format = AFMT_U8; - } - break; - case AUDIO_S8: - if ( value & AFMT_S8 ) { - format = AFMT_S8; - } - break; - case AUDIO_S16LSB: - if ( value & AFMT_S16_LE ) { - format = AFMT_S16_LE; - } - break; - case AUDIO_S16MSB: - if ( value & AFMT_S16_BE ) { - format = AFMT_S16_BE; - } - break; - case AUDIO_U16LSB: - if ( value & AFMT_U16_LE ) { - format = AFMT_U16_LE; - } - break; - case AUDIO_U16MSB: - if ( value & AFMT_U16_BE ) { - format = AFMT_U16_BE; - } - 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; + switch (test_format) { + case AUDIO_U8: + if (value & AFMT_U8) { + format = AFMT_U8; + } + break; + case AUDIO_S8: + if (value & AFMT_S8) { + format = AFMT_S8; + } + break; + case AUDIO_S16LSB: + if (value & AFMT_S16_LE) { + format = AFMT_S16_LE; + } + break; + case AUDIO_S16MSB: + if (value & AFMT_S16_BE) { + format = AFMT_S16_BE; + } + break; + case AUDIO_U16LSB: + if (value & AFMT_U16_LE) { + format = AFMT_U16_LE; + } + break; + case AUDIO_U16MSB: + if (value & AFMT_U16_BE) { + format = AFMT_U16_BE; + } + 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; - /* Set the audio format */ - value = format; - if ( (ioctl(audio_fd, SNDCTL_DSP_SETFMT, &value) < 0) || - (value != format) ) { - SDL_SetError("Couldn't set audio format"); - return(-1); - } + /* Set the audio format */ + value = format; + if ((ioctl(audio_fd, SNDCTL_DSP_SETFMT, &value) < 0) || (value != format)) { + SDL_SetError("Couldn't set audio format"); + return (-1); + } - /* Set mono or stereo audio (currently only two channels supported) */ - stereo = (spec->channels > 1); - ioctl(audio_fd, SNDCTL_DSP_STEREO, &stereo); - if ( stereo ) { - spec->channels = 2; - } else { - spec->channels = 1; - } + /* Set mono or stereo audio (currently only two channels supported) */ + stereo = (spec->channels > 1); + ioctl(audio_fd, SNDCTL_DSP_STEREO, &stereo); + if (stereo) { + spec->channels = 2; + } else { + spec->channels = 1; + } - /* Because some drivers don't allow setting the buffer size - after setting the format, we must re-open the audio device - once we know what format and channels are supported - */ - if ( DMA_ReopenAudio(this, audiodev, format, stereo, spec) < 0 ) { - /* Error is set by DMA_ReopenAudio() */ - return(-1); - } + /* Because some drivers don't allow setting the buffer size + after setting the format, we must re-open the audio device + once we know what format and channels are supported + */ + if (DMA_ReopenAudio(this, audiodev, format, stereo, spec) < 0) { + /* Error is set by DMA_ReopenAudio() */ + return (-1); + } - /* Memory map the audio buffer */ - if ( ioctl(audio_fd, SNDCTL_DSP_GETOSPACE, &info) < 0 ) { - SDL_SetError("Couldn't get OSPACE parameters"); - return(-1); - } - spec->size = info.fragsize; - spec->samples = spec->size / ((spec->format & 0xFF) / 8); - spec->samples /= spec->channels; - num_buffers = info.fragstotal; - dma_len = num_buffers*spec->size; - dma_buf = (Uint8 *)mmap(NULL, dma_len, PROT_WRITE, MAP_SHARED, - audio_fd, 0); - if ( dma_buf == MAP_FAILED ) { - SDL_SetError("DMA memory map failed"); - dma_buf = NULL; - return(-1); - } - SDL_memset(dma_buf, spec->silence, dma_len); + /* Memory map the audio buffer */ + if (ioctl(audio_fd, SNDCTL_DSP_GETOSPACE, &info) < 0) { + SDL_SetError("Couldn't get OSPACE parameters"); + return (-1); + } + spec->size = info.fragsize; + spec->samples = spec->size / ((spec->format & 0xFF) / 8); + spec->samples /= spec->channels; + num_buffers = info.fragstotal; + dma_len = num_buffers * spec->size; + dma_buf = (Uint8 *) mmap(NULL, dma_len, PROT_WRITE, MAP_SHARED, + audio_fd, 0); + if (dma_buf == MAP_FAILED) { + SDL_SetError("DMA memory map failed"); + dma_buf = NULL; + return (-1); + } + SDL_memset(dma_buf, spec->silence, dma_len); - /* Check to see if we need to use select() workaround */ - { char *workaround; - workaround = SDL_getenv("SDL_DSP_NOSELECT"); - if ( workaround ) { - frame_ticks = (float)(spec->samples*1000)/spec->freq; - next_frame = SDL_GetTicks()+frame_ticks; - } - } + /* Check to see if we need to use select() workaround */ + { + char *workaround; + workaround = SDL_getenv("SDL_DSP_NOSELECT"); + if (workaround) { + frame_ticks = (float) (spec->samples * 1000) / spec->freq; + next_frame = SDL_GetTicks() + frame_ticks; + } + } - /* Trigger audio playback */ - value = 0; - ioctl(audio_fd, SNDCTL_DSP_SETTRIGGER, &value); - value = PCM_ENABLE_OUTPUT; - if ( ioctl(audio_fd, SNDCTL_DSP_SETTRIGGER, &value) < 0 ) { - SDL_SetError("Couldn't trigger audio output"); - return(-1); - } + /* Trigger audio playback */ + value = 0; + ioctl(audio_fd, SNDCTL_DSP_SETTRIGGER, &value); + value = PCM_ENABLE_OUTPUT; + if (ioctl(audio_fd, SNDCTL_DSP_SETTRIGGER, &value) < 0) { + SDL_SetError("Couldn't trigger audio output"); + return (-1); + } - /* Get the parent process id (we're the parent of the audio thread) */ - parent = getpid(); + /* Get the parent process id (we're the parent of the audio thread) */ + parent = getpid(); - /* We're ready to rock and roll. :-) */ - return(0); + /* We're ready to rock and roll. :-) */ + return (0); } + +/* vi: set ts=4 sw=4 expandtab: */