diff options
Diffstat (limited to '3rdparty/SDL2/src/audio/alsa/SDL_alsa_audio.c')
-rw-r--r-- | 3rdparty/SDL2/src/audio/alsa/SDL_alsa_audio.c | 983 |
1 files changed, 0 insertions, 983 deletions
diff --git a/3rdparty/SDL2/src/audio/alsa/SDL_alsa_audio.c b/3rdparty/SDL2/src/audio/alsa/SDL_alsa_audio.c deleted file mode 100644 index 574d51bd5ec..00000000000 --- a/3rdparty/SDL2/src/audio/alsa/SDL_alsa_audio.c +++ /dev/null @@ -1,983 +0,0 @@ -/* - Simple DirectMedia Layer - Copyright (C) 1997-2016 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_ALSA - -/* Allow access to a raw mixing buffer */ - -#include <sys/types.h> -#include <signal.h> /* For kill() */ -#include <errno.h> -#include <string.h> - -#include "SDL_assert.h" -#include "SDL_timer.h" -#include "SDL_audio.h" -#include "../SDL_audio_c.h" -#include "SDL_alsa_audio.h" - -#ifdef SDL_AUDIO_DRIVER_ALSA_DYNAMIC -#include "SDL_loadso.h" -#endif - -static int (*ALSA_snd_pcm_open) - (snd_pcm_t **, const char *, snd_pcm_stream_t, int); -static int (*ALSA_snd_pcm_close) (snd_pcm_t * pcm); -static snd_pcm_sframes_t (*ALSA_snd_pcm_writei) - (snd_pcm_t *, const void *, snd_pcm_uframes_t); -static snd_pcm_sframes_t (*ALSA_snd_pcm_readi) - (snd_pcm_t *, void *, snd_pcm_uframes_t); -static int (*ALSA_snd_pcm_recover) (snd_pcm_t *, int, int); -static int (*ALSA_snd_pcm_prepare) (snd_pcm_t *); -static int (*ALSA_snd_pcm_drain) (snd_pcm_t *); -static const char *(*ALSA_snd_strerror) (int); -static size_t(*ALSA_snd_pcm_hw_params_sizeof) (void); -static size_t(*ALSA_snd_pcm_sw_params_sizeof) (void); -static void (*ALSA_snd_pcm_hw_params_copy) - (snd_pcm_hw_params_t *, const snd_pcm_hw_params_t *); -static int (*ALSA_snd_pcm_hw_params_any) (snd_pcm_t *, snd_pcm_hw_params_t *); -static int (*ALSA_snd_pcm_hw_params_set_access) - (snd_pcm_t *, snd_pcm_hw_params_t *, snd_pcm_access_t); -static int (*ALSA_snd_pcm_hw_params_set_format) - (snd_pcm_t *, snd_pcm_hw_params_t *, snd_pcm_format_t); -static int (*ALSA_snd_pcm_hw_params_set_channels) - (snd_pcm_t *, snd_pcm_hw_params_t *, unsigned int); -static int (*ALSA_snd_pcm_hw_params_get_channels) - (const snd_pcm_hw_params_t *, unsigned int *); -static int (*ALSA_snd_pcm_hw_params_set_rate_near) - (snd_pcm_t *, snd_pcm_hw_params_t *, unsigned int *, int *); -static int (*ALSA_snd_pcm_hw_params_set_period_size_near) - (snd_pcm_t *, snd_pcm_hw_params_t *, snd_pcm_uframes_t *, int *); -static int (*ALSA_snd_pcm_hw_params_get_period_size) - (const snd_pcm_hw_params_t *, snd_pcm_uframes_t *, int *); -static int (*ALSA_snd_pcm_hw_params_set_periods_near) - (snd_pcm_t *, snd_pcm_hw_params_t *, unsigned int *, int *); -static int (*ALSA_snd_pcm_hw_params_get_periods) - (const snd_pcm_hw_params_t *, unsigned int *, int *); -static int (*ALSA_snd_pcm_hw_params_set_buffer_size_near) - (snd_pcm_t *pcm, snd_pcm_hw_params_t *, snd_pcm_uframes_t *); -static int (*ALSA_snd_pcm_hw_params_get_buffer_size) - (const snd_pcm_hw_params_t *, snd_pcm_uframes_t *); -static int (*ALSA_snd_pcm_hw_params) (snd_pcm_t *, snd_pcm_hw_params_t *); -static int (*ALSA_snd_pcm_sw_params_current) (snd_pcm_t *, - snd_pcm_sw_params_t *); -static int (*ALSA_snd_pcm_sw_params_set_start_threshold) - (snd_pcm_t *, snd_pcm_sw_params_t *, snd_pcm_uframes_t); -static int (*ALSA_snd_pcm_sw_params) (snd_pcm_t *, snd_pcm_sw_params_t *); -static int (*ALSA_snd_pcm_nonblock) (snd_pcm_t *, int); -static int (*ALSA_snd_pcm_wait)(snd_pcm_t *, int); -static int (*ALSA_snd_pcm_sw_params_set_avail_min) - (snd_pcm_t *, snd_pcm_sw_params_t *, snd_pcm_uframes_t); -static int (*ALSA_snd_pcm_reset)(snd_pcm_t *); -static int (*ALSA_snd_device_name_hint) (int, const char *, void ***); -static char* (*ALSA_snd_device_name_get_hint) (const void *, const char *); -static int (*ALSA_snd_device_name_free_hint) (void **); - -#ifdef SDL_AUDIO_DRIVER_ALSA_DYNAMIC -#define snd_pcm_hw_params_sizeof ALSA_snd_pcm_hw_params_sizeof -#define snd_pcm_sw_params_sizeof ALSA_snd_pcm_sw_params_sizeof - -static const char *alsa_library = SDL_AUDIO_DRIVER_ALSA_DYNAMIC; -static void *alsa_handle = NULL; - -static int -load_alsa_sym(const char *fn, void **addr) -{ - *addr = SDL_LoadFunction(alsa_handle, fn); - if (*addr == NULL) { - /* Don't call SDL_SetError(): SDL_LoadFunction already did. */ - return 0; - } - - return 1; -} - -/* cast funcs to char* first, to please GCC's strict aliasing rules. */ -#define SDL_ALSA_SYM(x) \ - if (!load_alsa_sym(#x, (void **) (char *) &ALSA_##x)) return -1 -#else -#define SDL_ALSA_SYM(x) ALSA_##x = x -#endif - -static int -load_alsa_syms(void) -{ - SDL_ALSA_SYM(snd_pcm_open); - SDL_ALSA_SYM(snd_pcm_close); - SDL_ALSA_SYM(snd_pcm_writei); - SDL_ALSA_SYM(snd_pcm_readi); - SDL_ALSA_SYM(snd_pcm_recover); - SDL_ALSA_SYM(snd_pcm_prepare); - SDL_ALSA_SYM(snd_pcm_drain); - SDL_ALSA_SYM(snd_strerror); - SDL_ALSA_SYM(snd_pcm_hw_params_sizeof); - SDL_ALSA_SYM(snd_pcm_sw_params_sizeof); - SDL_ALSA_SYM(snd_pcm_hw_params_copy); - SDL_ALSA_SYM(snd_pcm_hw_params_any); - SDL_ALSA_SYM(snd_pcm_hw_params_set_access); - SDL_ALSA_SYM(snd_pcm_hw_params_set_format); - SDL_ALSA_SYM(snd_pcm_hw_params_set_channels); - SDL_ALSA_SYM(snd_pcm_hw_params_get_channels); - SDL_ALSA_SYM(snd_pcm_hw_params_set_rate_near); - SDL_ALSA_SYM(snd_pcm_hw_params_set_period_size_near); - SDL_ALSA_SYM(snd_pcm_hw_params_get_period_size); - SDL_ALSA_SYM(snd_pcm_hw_params_set_periods_near); - SDL_ALSA_SYM(snd_pcm_hw_params_get_periods); - SDL_ALSA_SYM(snd_pcm_hw_params_set_buffer_size_near); - SDL_ALSA_SYM(snd_pcm_hw_params_get_buffer_size); - SDL_ALSA_SYM(snd_pcm_hw_params); - SDL_ALSA_SYM(snd_pcm_sw_params_current); - SDL_ALSA_SYM(snd_pcm_sw_params_set_start_threshold); - SDL_ALSA_SYM(snd_pcm_sw_params); - SDL_ALSA_SYM(snd_pcm_nonblock); - SDL_ALSA_SYM(snd_pcm_wait); - SDL_ALSA_SYM(snd_pcm_sw_params_set_avail_min); - SDL_ALSA_SYM(snd_pcm_reset); - SDL_ALSA_SYM(snd_device_name_hint); - SDL_ALSA_SYM(snd_device_name_get_hint); - SDL_ALSA_SYM(snd_device_name_free_hint); - - return 0; -} - -#undef SDL_ALSA_SYM - -#ifdef SDL_AUDIO_DRIVER_ALSA_DYNAMIC - -static void -UnloadALSALibrary(void) -{ - if (alsa_handle != NULL) { - SDL_UnloadObject(alsa_handle); - alsa_handle = NULL; - } -} - -static int -LoadALSALibrary(void) -{ - int retval = 0; - if (alsa_handle == NULL) { - alsa_handle = SDL_LoadObject(alsa_library); - if (alsa_handle == NULL) { - retval = -1; - /* Don't call SDL_SetError(): SDL_LoadObject already did. */ - } else { - retval = load_alsa_syms(); - if (retval < 0) { - UnloadALSALibrary(); - } - } - } - return retval; -} - -#else - -static void -UnloadALSALibrary(void) -{ -} - -static int -LoadALSALibrary(void) -{ - load_alsa_syms(); - return 0; -} - -#endif /* SDL_AUDIO_DRIVER_ALSA_DYNAMIC */ - -static const char * -get_audio_device(void *handle, const int channels) -{ - const char *device; - - if (handle != NULL) { - return (const char *) handle; - } - - /* !!! FIXME: we also check "SDL_AUDIO_DEVICE_NAME" at the higher level. */ - device = SDL_getenv("AUDIODEV"); /* Is there a standard variable name? */ - if (device != NULL) { - return device; - } - - if (channels == 6) { - return "plug:surround51"; - } else if (channels == 4) { - return "plug:surround40"; - } - - return "default"; -} - - -/* This function waits until it is possible to write a full sound buffer */ -static void -ALSA_WaitDevice(_THIS) -{ - /* We're in blocking mode, so there's nothing to do here */ -} - - -/* !!! FIXME: is there a channel swizzler in alsalib instead? */ -/* - * http://bugzilla.libsdl.org/show_bug.cgi?id=110 - * "For Linux ALSA, this is FL-FR-RL-RR-C-LFE - * and for Windows DirectX [and CoreAudio], this is FL-FR-C-LFE-RL-RR" - */ -#define SWIZ6(T, buf, numframes) \ - T *ptr = (T *) buf; \ - Uint32 i; \ - for (i = 0; i < numframes; i++, ptr += 6) { \ - T tmp; \ - tmp = ptr[2]; ptr[2] = ptr[4]; ptr[4] = tmp; \ - tmp = ptr[3]; ptr[3] = ptr[5]; ptr[5] = tmp; \ - } - -static SDL_INLINE void -swizzle_alsa_channels_6_64bit(void *buffer, Uint32 bufferlen) -{ - SWIZ6(Uint64, buffer, bufferlen); -} - -static SDL_INLINE void -swizzle_alsa_channels_6_32bit(void *buffer, Uint32 bufferlen) -{ - SWIZ6(Uint32, buffer, bufferlen); -} - -static SDL_INLINE void -swizzle_alsa_channels_6_16bit(void *buffer, Uint32 bufferlen) -{ - SWIZ6(Uint16, buffer, bufferlen); -} - -static SDL_INLINE void -swizzle_alsa_channels_6_8bit(void *buffer, Uint32 bufferlen) -{ - SWIZ6(Uint8, buffer, bufferlen); -} - -#undef SWIZ6 - - -/* - * Called right before feeding this->hidden->mixbuf to the hardware. Swizzle - * channels from Windows/Mac order to the format alsalib will want. - */ -static SDL_INLINE void -swizzle_alsa_channels(_THIS, void *buffer, Uint32 bufferlen) -{ - if (this->spec.channels == 6) { - switch (SDL_AUDIO_BITSIZE(this->spec.format)) { - case 8: swizzle_alsa_channels_6_8bit(buffer, bufferlen); break; - case 16: swizzle_alsa_channels_6_16bit(buffer, bufferlen); break; - case 32: swizzle_alsa_channels_6_32bit(buffer, bufferlen); break; - case 64: swizzle_alsa_channels_6_64bit(buffer, bufferlen); break; - default: SDL_assert(!"unhandled bitsize"); break; - } - } - - /* !!! FIXME: update this for 7.1 if needed, later. */ -} - - -static void -ALSA_PlayDevice(_THIS) -{ - const Uint8 *sample_buf = (const Uint8 *) this->hidden->mixbuf; - const int frame_size = (((int) SDL_AUDIO_BITSIZE(this->spec.format)) / 8) * - this->spec.channels; - snd_pcm_uframes_t frames_left = ((snd_pcm_uframes_t) this->spec.samples); - - swizzle_alsa_channels(this, this->hidden->mixbuf, frames_left); - - while ( frames_left > 0 && SDL_AtomicGet(&this->enabled) ) { - int status; - - /* This wait is a work-around for a hang when USB devices are - unplugged. Normally it should not result in any waiting, - but in the case of a USB unplug, it serves as a way to - join the playback thread after the timeout occurs */ - status = ALSA_snd_pcm_wait(this->hidden->pcm_handle, 1000); - if (status == 0) { - /*fprintf(stderr, "ALSA timeout waiting for available buffer space\n");*/ - SDL_OpenedAudioDeviceDisconnected(this); - return; - } - - status = ALSA_snd_pcm_writei(this->hidden->pcm_handle, - sample_buf, frames_left); - - if (status < 0) { - if (status == -EAGAIN) { - /* Apparently snd_pcm_recover() doesn't handle this case - - does it assume snd_pcm_wait() above? */ - SDL_Delay(1); - continue; - } - status = ALSA_snd_pcm_recover(this->hidden->pcm_handle, status, 0); - if (status < 0) { - /* Hmm, not much we can do - abort */ - fprintf(stderr, "ALSA write failed (unrecoverable): %s\n", - ALSA_snd_strerror(status)); - SDL_OpenedAudioDeviceDisconnected(this); - return; - } - continue; - } - sample_buf += status * frame_size; - frames_left -= status; - } -} - -static Uint8 * -ALSA_GetDeviceBuf(_THIS) -{ - return (this->hidden->mixbuf); -} - -static int -ALSA_CaptureFromDevice(_THIS, void *buffer, int buflen) -{ - Uint8 *sample_buf = (Uint8 *) buffer; - const int frame_size = (((int) SDL_AUDIO_BITSIZE(this->spec.format)) / 8) * - this->spec.channels; - const int total_frames = buflen / frame_size; - snd_pcm_uframes_t frames_left = total_frames; - - SDL_assert((buflen % frame_size) == 0); - - while ( frames_left > 0 && SDL_AtomicGet(&this->enabled) ) { - /* !!! FIXME: This works, but needs more testing before going live */ - /* ALSA_snd_pcm_wait(this->hidden->pcm_handle, -1); */ - int status = ALSA_snd_pcm_readi(this->hidden->pcm_handle, - sample_buf, frames_left); - - if (status < 0) { - /*printf("ALSA: capture error %d\n", status);*/ - if (status == -EAGAIN) { - /* Apparently snd_pcm_recover() doesn't handle this case - - does it assume snd_pcm_wait() above? */ - SDL_Delay(1); - continue; - } - status = ALSA_snd_pcm_recover(this->hidden->pcm_handle, status, 0); - if (status < 0) { - /* Hmm, not much we can do - abort */ - fprintf(stderr, "ALSA read failed (unrecoverable): %s\n", - ALSA_snd_strerror(status)); - return -1; - } - continue; - } - - /*printf("ALSA: captured %d bytes\n", status * frame_size);*/ - sample_buf += status * frame_size; - frames_left -= status; - } - - swizzle_alsa_channels(this, buffer, total_frames - frames_left); - - return (total_frames - frames_left) * frame_size; -} - -static void -ALSA_FlushCapture(_THIS) -{ - ALSA_snd_pcm_reset(this->hidden->pcm_handle); -} - -static void -ALSA_CloseDevice(_THIS) -{ - if (this->hidden->pcm_handle) { - /* Wait for the submitted audio to drain - ALSA_snd_pcm_drop() can hang, so don't use that. - */ - Uint32 delay = ((this->spec.samples * 1000) / this->spec.freq) * 2; - SDL_Delay(delay); - - ALSA_snd_pcm_close(this->hidden->pcm_handle); - } - SDL_free(this->hidden->mixbuf); - SDL_free(this->hidden); -} - -static int -ALSA_finalize_hardware(_THIS, snd_pcm_hw_params_t *hwparams, int override) -{ - int status; - snd_pcm_uframes_t bufsize; - - /* "set" the hardware with the desired parameters */ - status = ALSA_snd_pcm_hw_params(this->hidden->pcm_handle, hwparams); - if ( status < 0 ) { - return(-1); - } - - /* Get samples for the actual buffer size */ - status = ALSA_snd_pcm_hw_params_get_buffer_size(hwparams, &bufsize); - if ( status < 0 ) { - return(-1); - } - if ( !override && bufsize != this->spec.samples * 2 ) { - return(-1); - } - - /* !!! FIXME: Is this safe to do? */ - this->spec.samples = bufsize / 2; - - /* This is useful for debugging */ - if ( SDL_getenv("SDL_AUDIO_ALSA_DEBUG") ) { - snd_pcm_uframes_t persize = 0; - unsigned int periods = 0; - - ALSA_snd_pcm_hw_params_get_period_size(hwparams, &persize, NULL); - ALSA_snd_pcm_hw_params_get_periods(hwparams, &periods, NULL); - - fprintf(stderr, - "ALSA: period size = %ld, periods = %u, buffer size = %lu\n", - persize, periods, bufsize); - } - - return(0); -} - -static int -ALSA_set_period_size(_THIS, snd_pcm_hw_params_t *params, int override) -{ - const char *env; - int status; - snd_pcm_hw_params_t *hwparams; - snd_pcm_uframes_t frames; - unsigned int periods; - - /* Copy the hardware parameters for this setup */ - snd_pcm_hw_params_alloca(&hwparams); - ALSA_snd_pcm_hw_params_copy(hwparams, params); - - if ( !override ) { - env = SDL_getenv("SDL_AUDIO_ALSA_SET_PERIOD_SIZE"); - if ( env ) { - override = SDL_atoi(env); - if ( override == 0 ) { - return(-1); - } - } - } - - frames = this->spec.samples; - status = ALSA_snd_pcm_hw_params_set_period_size_near( - this->hidden->pcm_handle, hwparams, &frames, NULL); - if ( status < 0 ) { - return(-1); - } - - periods = 2; - status = ALSA_snd_pcm_hw_params_set_periods_near( - this->hidden->pcm_handle, hwparams, &periods, NULL); - if ( status < 0 ) { - return(-1); - } - - return ALSA_finalize_hardware(this, hwparams, override); -} - -static int -ALSA_set_buffer_size(_THIS, snd_pcm_hw_params_t *params, int override) -{ - const char *env; - int status; - snd_pcm_hw_params_t *hwparams; - snd_pcm_uframes_t frames; - - /* Copy the hardware parameters for this setup */ - snd_pcm_hw_params_alloca(&hwparams); - ALSA_snd_pcm_hw_params_copy(hwparams, params); - - if ( !override ) { - env = SDL_getenv("SDL_AUDIO_ALSA_SET_BUFFER_SIZE"); - if ( env ) { - override = SDL_atoi(env); - if ( override == 0 ) { - return(-1); - } - } - } - - frames = this->spec.samples * 2; - status = ALSA_snd_pcm_hw_params_set_buffer_size_near( - this->hidden->pcm_handle, hwparams, &frames); - if ( status < 0 ) { - return(-1); - } - - return ALSA_finalize_hardware(this, hwparams, override); -} - -static int -ALSA_OpenDevice(_THIS, void *handle, const char *devname, int iscapture) -{ - int status = 0; - snd_pcm_t *pcm_handle = NULL; - snd_pcm_hw_params_t *hwparams = NULL; - snd_pcm_sw_params_t *swparams = NULL; - snd_pcm_format_t format = 0; - SDL_AudioFormat test_format = 0; - unsigned int rate = 0; - unsigned int channels = 0; - - /* 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 */ - /* Name of device should depend on # channels in spec */ - status = ALSA_snd_pcm_open(&pcm_handle, - get_audio_device(handle, this->spec.channels), - iscapture ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK, - SND_PCM_NONBLOCK); - - if (status < 0) { - return SDL_SetError("ALSA: Couldn't open audio device: %s", - ALSA_snd_strerror(status)); - } - - this->hidden->pcm_handle = pcm_handle; - - /* Figure out what the hardware is capable of */ - snd_pcm_hw_params_alloca(&hwparams); - status = ALSA_snd_pcm_hw_params_any(pcm_handle, hwparams); - if (status < 0) { - return SDL_SetError("ALSA: Couldn't get hardware config: %s", - ALSA_snd_strerror(status)); - } - - /* SDL only uses interleaved sample output */ - status = ALSA_snd_pcm_hw_params_set_access(pcm_handle, hwparams, - SND_PCM_ACCESS_RW_INTERLEAVED); - if (status < 0) { - return SDL_SetError("ALSA: Couldn't set interleaved access: %s", - ALSA_snd_strerror(status)); - } - - /* Try for a closest match on audio format */ - status = -1; - for (test_format = SDL_FirstAudioFormat(this->spec.format); - test_format && (status < 0);) { - status = 0; /* if we can't support a format, it'll become -1. */ - switch (test_format) { - case AUDIO_U8: - format = SND_PCM_FORMAT_U8; - break; - case AUDIO_S8: - format = SND_PCM_FORMAT_S8; - break; - case AUDIO_S16LSB: - format = SND_PCM_FORMAT_S16_LE; - break; - case AUDIO_S16MSB: - format = SND_PCM_FORMAT_S16_BE; - break; - case AUDIO_U16LSB: - format = SND_PCM_FORMAT_U16_LE; - break; - case AUDIO_U16MSB: - format = SND_PCM_FORMAT_U16_BE; - break; - case AUDIO_S32LSB: - format = SND_PCM_FORMAT_S32_LE; - break; - case AUDIO_S32MSB: - format = SND_PCM_FORMAT_S32_BE; - break; - case AUDIO_F32LSB: - format = SND_PCM_FORMAT_FLOAT_LE; - break; - case AUDIO_F32MSB: - format = SND_PCM_FORMAT_FLOAT_BE; - break; - default: - status = -1; - break; - } - if (status >= 0) { - status = ALSA_snd_pcm_hw_params_set_format(pcm_handle, - hwparams, format); - } - if (status < 0) { - test_format = SDL_NextAudioFormat(); - } - } - if (status < 0) { - return SDL_SetError("ALSA: Couldn't find any hardware audio formats"); - } - this->spec.format = test_format; - - /* Set the number of channels */ - status = ALSA_snd_pcm_hw_params_set_channels(pcm_handle, hwparams, - this->spec.channels); - channels = this->spec.channels; - if (status < 0) { - status = ALSA_snd_pcm_hw_params_get_channels(hwparams, &channels); - if (status < 0) { - return SDL_SetError("ALSA: Couldn't set audio channels"); - } - this->spec.channels = channels; - } - - /* Set the audio rate */ - rate = this->spec.freq; - status = ALSA_snd_pcm_hw_params_set_rate_near(pcm_handle, hwparams, - &rate, NULL); - if (status < 0) { - return SDL_SetError("ALSA: Couldn't set audio frequency: %s", - ALSA_snd_strerror(status)); - } - this->spec.freq = rate; - - /* Set the buffer size, in samples */ - if ( ALSA_set_period_size(this, hwparams, 0) < 0 && - ALSA_set_buffer_size(this, hwparams, 0) < 0 ) { - /* Failed to set desired buffer size, do the best you can... */ - status = ALSA_set_period_size(this, hwparams, 1); - if (status < 0) { - return SDL_SetError("Couldn't set hardware audio parameters: %s", ALSA_snd_strerror(status)); - } - } - /* Set the software parameters */ - snd_pcm_sw_params_alloca(&swparams); - status = ALSA_snd_pcm_sw_params_current(pcm_handle, swparams); - if (status < 0) { - return SDL_SetError("ALSA: Couldn't get software config: %s", - ALSA_snd_strerror(status)); - } - status = ALSA_snd_pcm_sw_params_set_avail_min(pcm_handle, swparams, this->spec.samples); - if (status < 0) { - return SDL_SetError("Couldn't set minimum available samples: %s", - ALSA_snd_strerror(status)); - } - status = - ALSA_snd_pcm_sw_params_set_start_threshold(pcm_handle, swparams, 1); - if (status < 0) { - return SDL_SetError("ALSA: Couldn't set start threshold: %s", - ALSA_snd_strerror(status)); - } - status = ALSA_snd_pcm_sw_params(pcm_handle, swparams); - if (status < 0) { - return SDL_SetError("Couldn't set software audio parameters: %s", - ALSA_snd_strerror(status)); - } - - /* Calculate the final parameters for this audio specification */ - SDL_CalculateAudioSpec(&this->spec); - - /* Allocate mixing buffer */ - if (!iscapture) { - this->hidden->mixlen = this->spec.size; - this->hidden->mixbuf = (Uint8 *) SDL_malloc(this->hidden->mixlen); - if (this->hidden->mixbuf == NULL) { - return SDL_OutOfMemory(); - } - SDL_memset(this->hidden->mixbuf, this->spec.silence, this->hidden->mixlen); - } - - /* Switch to blocking mode for playback */ - ALSA_snd_pcm_nonblock(pcm_handle, 0); - - /* We're ready to rock and roll. :-) */ - return 0; -} - -typedef struct ALSA_Device -{ - char *name; - SDL_bool iscapture; - struct ALSA_Device *next; -} ALSA_Device; - -static void -add_device(const int iscapture, const char *name, void *hint, ALSA_Device **pSeen) -{ - ALSA_Device *dev = SDL_malloc(sizeof (ALSA_Device)); - char *desc = ALSA_snd_device_name_get_hint(hint, "DESC"); - char *handle = NULL; - char *ptr; - - if (!desc) { - SDL_free(dev); - return; - } else if (!dev) { - free(desc); - return; - } - - SDL_assert(name != NULL); - - /* some strings have newlines, like "HDA NVidia, HDMI 0\nHDMI Audio Output". - just chop the extra lines off, this seems to get a reasonable device - name without extra details. */ - if ((ptr = strchr(desc, '\n')) != NULL) { - *ptr = '\0'; - } - - /*printf("ALSA: adding %s device '%s' (%s)\n", iscapture ? "capture" : "output", name, desc);*/ - - handle = SDL_strdup(name); - if (!handle) { - free(desc); - SDL_free(dev); - return; - } - - SDL_AddAudioDevice(iscapture, desc, handle); - free(desc); - - dev->name = handle; - dev->iscapture = iscapture; - dev->next = *pSeen; - *pSeen = dev; -} - - -static SDL_atomic_t ALSA_hotplug_shutdown; -static SDL_Thread *ALSA_hotplug_thread; - -static int SDLCALL -ALSA_HotplugThread(void *arg) -{ - SDL_sem *first_run_semaphore = (SDL_sem *) arg; - ALSA_Device *devices = NULL; - ALSA_Device *next; - ALSA_Device *dev; - Uint32 ticks; - - while (!SDL_AtomicGet(&ALSA_hotplug_shutdown)) { - void **hints = NULL; - if (ALSA_snd_device_name_hint(-1, "pcm", &hints) != -1) { - ALSA_Device *unseen = devices; - ALSA_Device *seen = NULL; - ALSA_Device *prev; - int i, j; - const char *match = NULL; - int bestmatch = 0xFFFF; - size_t match_len = 0; - int defaultdev = -1; - static const char * const prefixes[] = { - "hw:", "sysdefault:", "default:", NULL - }; - - /* Apparently there are several different ways that ALSA lists - actual hardware. It could be prefixed with "hw:" or "default:" - or "sysdefault:" and maybe others. Go through the list and see - if we can find a preferred prefix for the system. */ - for (i = 0; hints[i]; i++) { - char *name = ALSA_snd_device_name_get_hint(hints[i], "NAME"); - if (!name) { - continue; - } - - /* full name, not a prefix */ - if ((defaultdev == -1) && (SDL_strcmp(name, "default") == 0)) { - defaultdev = i; - } - - for (j = 0; prefixes[j]; j++) { - const char *prefix = prefixes[j]; - const size_t prefixlen = SDL_strlen(prefix); - if (SDL_strncmp(name, prefix, prefixlen) == 0) { - if (j < bestmatch) { - bestmatch = j; - match = prefix; - match_len = prefixlen; - } - } - } - - free(name); - } - - /* look through the list of device names to find matches */ - for (i = 0; hints[i]; i++) { - char *name; - - /* if we didn't find a device name prefix we like at all... */ - if ((!match) && (defaultdev != i)) { - continue; /* ...skip anything that isn't the default device. */ - } - - name = ALSA_snd_device_name_get_hint(hints[i], "NAME"); - if (!name) { - continue; - } - - /* only want physical hardware interfaces */ - if (!match || (SDL_strncmp(name, match, match_len) == 0)) { - char *ioid = ALSA_snd_device_name_get_hint(hints[i], "IOID"); - const SDL_bool isoutput = (ioid == NULL) || (SDL_strcmp(ioid, "Output") == 0); - const SDL_bool isinput = (ioid == NULL) || (SDL_strcmp(ioid, "Input") == 0); - SDL_bool have_output = SDL_FALSE; - SDL_bool have_input = SDL_FALSE; - - free(ioid); - - if (!isoutput && !isinput) { - free(name); - continue; - } - - prev = NULL; - for (dev = unseen; dev; dev = next) { - next = dev->next; - if ( (SDL_strcmp(dev->name, name) == 0) && (((isinput) && dev->iscapture) || ((isoutput) && !dev->iscapture)) ) { - if (prev) { - prev->next = next; - } else { - unseen = next; - } - dev->next = seen; - seen = dev; - if (isinput) have_input = SDL_TRUE; - if (isoutput) have_output = SDL_TRUE; - } else { - prev = dev; - } - } - - if (isinput && !have_input) { - add_device(SDL_TRUE, name, hints[i], &seen); - } - if (isoutput && !have_output) { - add_device(SDL_FALSE, name, hints[i], &seen); - } - } - - free(name); - } - - ALSA_snd_device_name_free_hint(hints); - - devices = seen; /* now we have a known-good list of attached devices. */ - - /* report anything still in unseen as removed. */ - for (dev = unseen; dev; dev = next) { - /*printf("ALSA: removing %s device '%s'\n", dev->iscapture ? "capture" : "output", dev->name);*/ - next = dev->next; - SDL_RemoveAudioDevice(dev->iscapture, dev->name); - SDL_free(dev->name); - SDL_free(dev); - } - } - - /* On first run, tell ALSA_DetectDevices() that we have a complete device list so it can return. */ - if (first_run_semaphore) { - SDL_SemPost(first_run_semaphore); - first_run_semaphore = NULL; /* let other thread clean it up. */ - } - - /* Block awhile before checking again, unless we're told to stop. */ - ticks = SDL_GetTicks() + 5000; - while (!SDL_AtomicGet(&ALSA_hotplug_shutdown) && !SDL_TICKS_PASSED(SDL_GetTicks(), ticks)) { - SDL_Delay(100); - } - } - - /* Shutting down! Clean up any data we've gathered. */ - for (dev = devices; dev; dev = next) { - /*printf("ALSA: at shutdown, removing %s device '%s'\n", dev->iscapture ? "capture" : "output", dev->name);*/ - next = dev->next; - SDL_free(dev->name); - SDL_free(dev); - } - - return 0; -} - -static void -ALSA_DetectDevices(void) -{ - /* Start the device detection thread here, wait for an initial iteration to complete. */ - SDL_sem *semaphore = SDL_CreateSemaphore(0); - if (!semaphore) { - return; /* oh well. */ - } - - SDL_AtomicSet(&ALSA_hotplug_shutdown, 0); - - ALSA_hotplug_thread = SDL_CreateThread(ALSA_HotplugThread, "SDLHotplugALSA", semaphore); - if (ALSA_hotplug_thread) { - SDL_SemWait(semaphore); /* wait for the first iteration to finish. */ - } - - SDL_DestroySemaphore(semaphore); -} - -static void -ALSA_Deinitialize(void) -{ - if (ALSA_hotplug_thread != NULL) { - SDL_AtomicSet(&ALSA_hotplug_shutdown, 1); - SDL_WaitThread(ALSA_hotplug_thread, NULL); - ALSA_hotplug_thread = NULL; - } - - UnloadALSALibrary(); -} - -static int -ALSA_Init(SDL_AudioDriverImpl * impl) -{ - if (LoadALSALibrary() < 0) { - return 0; - } - - /* Set the function pointers */ - impl->DetectDevices = ALSA_DetectDevices; - impl->OpenDevice = ALSA_OpenDevice; - impl->WaitDevice = ALSA_WaitDevice; - impl->GetDeviceBuf = ALSA_GetDeviceBuf; - impl->PlayDevice = ALSA_PlayDevice; - impl->CloseDevice = ALSA_CloseDevice; - impl->Deinitialize = ALSA_Deinitialize; - impl->CaptureFromDevice = ALSA_CaptureFromDevice; - impl->FlushCapture = ALSA_FlushCapture; - - impl->HasCaptureSupport = SDL_TRUE; - - return 1; /* this audio target is available. */ -} - - -AudioBootStrap ALSA_bootstrap = { - "alsa", "ALSA PCM audio", ALSA_Init, 0 -}; - -#endif /* SDL_AUDIO_DRIVER_ALSA */ - -/* vi: set ts=4 sw=4 expandtab: */ |