view src/audio/macosx/SDL_coreaudio.c @ 3796:b19680c84cdf SDL-ryan-multiple-audio-device

Bunch of 1.3 audio cleanups to remove FIXMEs, get driver specific crap out of the core and into the drivers where it belongs, and push generic responsibilities out of the drivers and into the core where they belong.
author Ryan C. Gordon <icculus@icculus.org>
date Wed, 04 Oct 2006 19:54:23 +0000
parents 589bc3d060cd
children c8b3d3d13ed1
line wrap: on
line source

/*
    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"

#include <CoreAudio/CoreAudio.h>
#include <AudioUnit/AudioUnit.h>

#include "SDL_audio.h"
#include "../SDL_audio_c.h"
#include "../SDL_sysaudio.h"
#include "SDL_coreaudio.h"

#define DEBUG_COREAUDIO 0

typedef struct COREAUDIO_DeviceList
{
    AudioDeviceID id;
    const char *name;
} COREAUDIO_DeviceList;

static COREAUDIO_DeviceList *inputDevices = NULL;
static int inputDeviceCount = 0;
static COREAUDIO_DeviceList *outputDevices = NULL;
static int outputDeviceCount = 0;

static void
free_device_list(COREAUDIO_DeviceList **devices, int *devCount)
{
    if (*devices) {
        int i = *devCount;
        while (i--)
            SDL_free((void *) (*devices)[i].name);
        SDL_free(*devices);
        *devices = NULL;
    }
    *devCount = 0;
}


static void
build_device_list(int iscapture, COREAUDIO_DeviceList **devices, int *devCount)
{
    Boolean outWritable = 0;
    OSStatus result = noErr;
    UInt32 size = 0;
    AudioDeviceID *devs = NULL;
    UInt32 i = 0;
    UInt32 max = 0;

    free_device_list(devices, devCount);

    result = AudioHardwareGetPropertyInfo(kAudioHardwarePropertyDevices,
                                         &size, &outWritable);

    if (result != kAudioHardwareNoError)
        return;

    devs = (AudioDeviceID *) alloca(size);
    if (devs == NULL)
        return;

    max = size / sizeof (AudioDeviceID);
    *devices = (COREAUDIO_DeviceList *) SDL_malloc(max * sizeof (**devices));
    if (*devices == NULL)
        return;

    result = AudioHardwareGetProperty(kAudioHardwarePropertyDevices,
                                     &size, devs);
    if (result != kAudioHardwareNoError)
        return;

    for (i = 0; i < max; i++) {
        CFStringRef cfstr = NULL;
        char *ptr = NULL;
        AudioDeviceID dev = devs[i];
        AudioBufferList *buflist = NULL;
        int usable = 0;
        CFIndex len = 0;

        result = AudioDeviceGetPropertyInfo(dev, 0, iscapture,
                                      kAudioDevicePropertyStreamConfiguration,
                                      &size, &outWritable);
        if (result != noErr)
            continue;

        buflist = (AudioBufferList *) SDL_malloc(size);
        if (buflist == NULL)
            continue;

        result = AudioDeviceGetProperty(dev, 0, iscapture,
                                      kAudioDevicePropertyStreamConfiguration,
                                      &size, buflist);

        if (result == noErr) {
            UInt32 j;
            for (j = 0; j < buflist->mNumberBuffers; j++) {
                if (buflist->mBuffers[j].mNumberChannels > 0) {
                    usable = 1;
                    break;
                }
            }
        }

        SDL_free(buflist);

        if (!usable)
            continue;

        size = sizeof (CFStringRef);
        result = AudioDeviceGetProperty(dev, 0, iscapture,
                                        kAudioObjectPropertyName,
                                        &size, &cfstr);

        if (result != kAudioHardwareNoError)
            continue;

        len = CFStringGetMaximumSizeForEncoding(CFStringGetLength(cfstr),
                                                kCFStringEncodingUTF8);

        ptr = (char *) SDL_malloc(len + 1);
        usable = ( (ptr != NULL) &&
                (CFStringGetCString(cfstr,ptr,len+1,kCFStringEncodingUTF8)) );

        CFRelease(cfstr);

        if (usable) {
            len = strlen(ptr);
            /* Some devices have whitespace at the end...trim it. */
            while ((len > 0) && (ptr[len-1] == ' ')) {
                len--;
            }
            usable = (len > 0);
        }

        if (!usable) {
            SDL_free(ptr);
        } else {
            ptr[len] = '\0';

            #if DEBUG_COREAUDIO
            printf("COREAUDIO: Found %s device #%d: '%s' (devid %d)\n",
                    ((iscapture) ? "capture" : "output"),
                    (int) *devCount, ptr, (int) dev);
            #endif

            (*devices)[*devCount].id = dev;
            (*devices)[*devCount].name = ptr;
            (*devCount)++;
        }
    }
}

static inline void
build_device_lists(void)
{
    build_device_list(0, &outputDevices, &outputDeviceCount);
    build_device_list(1, &inputDevices, &inputDeviceCount);
}


static inline void
free_device_lists(void)
{
    free_device_list(&outputDevices, &outputDeviceCount);
    free_device_list(&inputDevices, &inputDeviceCount);
}


static int
find_device_id(const char *devname, int iscapture, AudioDeviceID *id)
{
    int i = ((iscapture) ? inputDeviceCount : outputDeviceCount);
    COREAUDIO_DeviceList *devs = ((iscapture) ? inputDevices : outputDevices);
    while (i--) {
        if (SDL_strcmp(devname, devs->name) == 0) {
            *id = devs->id;
            return 1;
        }
        devs++;
    }

    return 0;
}


/* Audio driver functions */

static int COREAUDIO_DetectDevices(int iscapture);
static const char *COREAUDIO_GetDeviceName(int index, int iscapture);
static int COREAUDIO_OpenDevice(_THIS, const char *devname, int iscapture);
static void COREAUDIO_WaitDevice(_THIS);
static void COREAUDIO_PlayDevice(_THIS);
static Uint8 *COREAUDIO_GetDeviceBuf(_THIS);
static void COREAUDIO_CloseDevice(_THIS);
static void COREAUDIO_Deinitialize(void);

/* Audio driver bootstrap functions */

static int
COREAUDIO_Available(void)
{
    return (1);
}

static int
COREAUDIO_Init(SDL_AudioDriverImpl *impl)
{
    /* Set the function pointers */
    impl->DetectDevices = COREAUDIO_DetectDevices;
    impl->GetDeviceName = COREAUDIO_GetDeviceName;
    impl->OpenDevice = COREAUDIO_OpenDevice;
    impl->WaitDevice = COREAUDIO_WaitDevice;
    impl->PlayDevice = COREAUDIO_PlayDevice;
    impl->GetDeviceBuf = COREAUDIO_GetDeviceBuf;
    impl->CloseDevice = COREAUDIO_CloseDevice;
    impl->Deinitialize = COREAUDIO_Deinitialize;
    impl->ProvidesOwnCallbackThread = 1;
    return 1;
}

AudioBootStrap COREAUDIO_bootstrap = {
    "coreaudio", "Mac OS X CoreAudio",
    COREAUDIO_Available, COREAUDIO_Init
};


static int
COREAUDIO_DetectDevices(int iscapture)
{
    if (iscapture) {
        build_device_list(1, &inputDevices, &inputDeviceCount);
        return inputDeviceCount;
    } else {
        build_device_list(0, &outputDevices, &outputDeviceCount);
        return outputDeviceCount;
    }

    return 0;  /* shouldn't ever hit this. */
}


static const char *
COREAUDIO_GetDeviceName(int index, int iscapture)
{
    if ((iscapture) && (index < inputDeviceCount)) {
        return inputDevices[index].name;
    } else if ((!iscapture) && (index < outputDeviceCount)) {
        return outputDevices[index].name;
    }

    SDL_SetError("No such device");
    return NULL;
}


static void
COREAUDIO_Deinitialize(void)
{
    free_device_lists();
}


/* The CoreAudio callback */
static OSStatus
outputCallback(void *inRefCon,
              AudioUnitRenderActionFlags *ioActionFlags,
              const AudioTimeStamp * inTimeStamp,
              UInt32 inBusNumber, UInt32 inNumberFrames,
              AudioBufferList *ioDataList)
{
    SDL_AudioDevice *this = (SDL_AudioDevice *) inRefCon;
    AudioBuffer *ioData = &ioDataList->mBuffers[0];
    UInt32 remaining, len;
    void *ptr;

    /*
     * !!! FIXME: I'm not sure if you can ever have more than one
     *            buffer, or what this signifies, or what to do with it...
     */
    if (ioDataList->mNumberBuffers != 1) {
        return noErr;
    }

    /* Only do anything if audio is enabled and not paused */
    if (!this->enabled || this->paused) {
        SDL_memset(ioData->mData, this->spec.silence, ioData->mDataByteSize);
        return 0;
    }

    /* No SDL conversion should be needed here, ever, since we accept
       any input format in OpenAudio, and leave the conversion to CoreAudio.
     */
    /*
       assert(!this->convert.needed);
       assert(this->spec.channels == ioData->mNumberChannels);
     */

    remaining = ioData->mDataByteSize;
    ptr = ioData->mData;
    while (remaining > 0) {
        if (this->hidden->bufferOffset >= this->hidden->bufferSize) {
            /* Generate the data */
            SDL_memset(this->hidden->buffer, this->spec.silence,
                       this->hidden->bufferSize);
            SDL_mutexP(this->mixer_lock);
            (*this->spec.callback) (this->spec.userdata, this->hidden->buffer,
                                    this->hidden->bufferSize);
            SDL_mutexV(this->mixer_lock);
            this->hidden->bufferOffset = 0;
        }

        len = this->hidden->bufferSize - this->hidden->bufferOffset;
        if (len > remaining)
            len = remaining;
        SDL_memcpy(ptr,
                    (char *) this->hidden->buffer + this->hidden->bufferOffset,
                    len);
        ptr = (char *) ptr + len;
        remaining -= len;
        this->hidden->bufferOffset += len;
    }

    return 0;
}

static OSStatus
inputCallback(void *inRefCon,
              AudioUnitRenderActionFlags *ioActionFlags,
              const AudioTimeStamp * inTimeStamp,
              UInt32 inBusNumber, UInt32 inNumberFrames,
              AudioBufferList *ioData)
{
    //err = AudioUnitRender(afr->fAudioUnit, ioActionFlags, inTimeStamp, inBusNumber, inNumberFrames, afr->fAudioBuffer);
    // !!! FIXME: write me!
    return noErr;
}


/* Dummy functions -- we don't use thread-based audio */
static void
COREAUDIO_WaitDevice(_THIS)
{
    return;
}

static void
COREAUDIO_PlayDevice(_THIS)
{
    return;
}

static Uint8 *
COREAUDIO_GetDeviceBuf(_THIS)
{
    return (NULL);
}

static void
COREAUDIO_CloseDevice(_THIS)
{
    if (this->hidden != NULL) {
        OSStatus result = noErr;
        AURenderCallbackStruct callback;
        const AudioUnitElement output_bus = 0;
        const AudioUnitElement input_bus = 1;
        const int iscapture = this->iscapture;
        const AudioUnitElement bus = ((iscapture) ? input_bus : output_bus);
        const AudioUnitScope scope = ((iscapture) ? kAudioUnitScope_Output :
                                                    kAudioUnitScope_Input);

        /* stop processing the audio unit */
        result = AudioOutputUnitStop(this->hidden->audioUnit);

        /* Remove the input callback */
        memset(&callback, '\0', sizeof (AURenderCallbackStruct));
        result = AudioUnitSetProperty(this->hidden->audioUnit,
                                      kAudioUnitProperty_SetRenderCallback,
                                      scope, bus, &callback, sizeof (callback));

        CloseComponent(this->hidden->audioUnit);

        SDL_free(this->hidden->buffer);
        SDL_free(this->hidden);
        this->hidden = NULL;
    }
}


#define CHECK_RESULT(msg) \
    if (result != noErr) { \
        COREAUDIO_CloseDevice(this); \
        SDL_SetError("CoreAudio error (%s): %d", msg, (int) result); \
        return 0; \
    }

static int
find_device_by_name(_THIS, const char *devname, int iscapture)
{
    AudioDeviceID devid = 0;
    OSStatus result = noErr;
    UInt32 size = 0;
    UInt32 alive = 0;
    pid_t pid = 0;

    if (devname == NULL) {
        size = sizeof (AudioDeviceID);
        const AudioHardwarePropertyID propid =
                    ((iscapture) ? kAudioHardwarePropertyDefaultInputDevice :
                                   kAudioHardwarePropertyDefaultOutputDevice);

        result = AudioHardwareGetProperty(propid, &size, &devid);
        CHECK_RESULT("AudioHardwareGetProperty (default device)");
    } else {
        if (!find_device_id(devname, iscapture, &devid)) {
            SDL_SetError("CoreAudio: No such audio device.");
            return 0;
        }
    }

    size = sizeof (alive);
    result = AudioDeviceGetProperty(devid, 0, iscapture,
                                    kAudioDevicePropertyDeviceIsAlive,
                                    &size, &alive);
    CHECK_RESULT("AudioDeviceGetProperty (kAudioDevicePropertyDeviceIsAlive)");

    if (!alive) {
        SDL_SetError("CoreAudio: requested device exists, but isn't alive.");
        return 0;
    }

    size = sizeof (pid);
    result = AudioDeviceGetProperty(devid, 0, iscapture,
                                    kAudioDevicePropertyHogMode, &size, &pid);

    /* some devices don't support this property, so errors are fine here. */
    if ((result == noErr) && (pid != -1)) {
        SDL_SetError("CoreAudio: requested device is being hogged.");
        return 0;
    }

    this->hidden->deviceID = devid;
    return 1;
}


static int
prepare_audiounit(_THIS, const char *devname, int iscapture,
                  const AudioStreamBasicDescription *strdesc)
{
    OSStatus result = noErr;
    AURenderCallbackStruct callback;
    ComponentDescription desc;
    Component comp = NULL;
    int use_system_device = 0;
    UInt32 enableIO = 0;
    const AudioUnitElement output_bus = 0;
    const AudioUnitElement input_bus = 1;
    const AudioUnitElement bus = ((iscapture) ? input_bus : output_bus);
    const AudioUnitScope scope = ((iscapture) ? kAudioUnitScope_Output :
                                                kAudioUnitScope_Input);

    if (!find_device_by_name(this, devname, iscapture)) {
        SDL_SetError("Couldn't find requested CoreAudio device");
        return 0;
    }

    memset(&desc, '\0', sizeof(ComponentDescription));
    desc.componentType = kAudioUnitType_Output;
    desc.componentSubType = kAudioUnitSubType_HALOutput;
    desc.componentManufacturer = kAudioUnitManufacturer_Apple;

    comp = FindNextComponent(NULL, &desc);
    if (comp == NULL) {
        SDL_SetError("Couldn't find requested CoreAudio component");
        return 0;
    }

    /* Open & initialize the audio unit */
    result = OpenAComponent(comp, &this->hidden->audioUnit);
    CHECK_RESULT("OpenAComponent");

    // !!! FIXME: this is wrong?
    enableIO = ((iscapture) ? 1 : 0);
    result = AudioUnitSetProperty(this->hidden->audioUnit,
                                  kAudioOutputUnitProperty_EnableIO,
                                  kAudioUnitScope_Input, input_bus,
                                  &enableIO, sizeof (enableIO));
    CHECK_RESULT("AudioUnitSetProperty (kAudioUnitProperty_EnableIO input)");

    // !!! FIXME: this is wrong?
    enableIO = ((iscapture) ? 0 : 1);
    result = AudioUnitSetProperty(this->hidden->audioUnit,
                                  kAudioOutputUnitProperty_EnableIO,
                                  kAudioUnitScope_Output, output_bus,
                                  &enableIO, sizeof (enableIO));
    CHECK_RESULT("AudioUnitSetProperty (kAudioUnitProperty_EnableIO output)");

    result = AudioUnitSetProperty(this->hidden->audioUnit,
                                  kAudioOutputUnitProperty_CurrentDevice,
                                  kAudioUnitScope_Global, 0,
                                  &this->hidden->deviceID,
                                  sizeof (AudioDeviceID));
    CHECK_RESULT("AudioUnitSetProperty (kAudioOutputUnitProperty_CurrentDevice)");

    /* Set the data format of the audio unit. */
    result = AudioUnitSetProperty(this->hidden->audioUnit,
                                  kAudioUnitProperty_StreamFormat,
                                  scope, bus, strdesc, sizeof (*strdesc));
    CHECK_RESULT("AudioUnitSetProperty (kAudioUnitProperty_StreamFormat)");

    /* Set the audio callback */
    memset(&callback, '\0', sizeof (AURenderCallbackStruct));
    callback.inputProc = ((iscapture) ? inputCallback : outputCallback);
    callback.inputProcRefCon = this;
    result = AudioUnitSetProperty(this->hidden->audioUnit,
                                  kAudioUnitProperty_SetRenderCallback,
                                  scope, bus, &callback, sizeof (callback));
    CHECK_RESULT("AudioUnitSetProperty (kAudioUnitProperty_SetInputCallback)");

    /* Calculate the final parameters for this audio specification */
    SDL_CalculateAudioSpec(&this->spec);

    /* Allocate a sample buffer */
    this->hidden->bufferOffset = this->hidden->bufferSize = this->spec.size;
    this->hidden->buffer = SDL_malloc(this->hidden->bufferSize);

    result = AudioUnitInitialize(this->hidden->audioUnit);
    CHECK_RESULT("AudioUnitInitialize");

    /* Finally, start processing of the audio unit */
    result = AudioOutputUnitStart(this->hidden->audioUnit);
    CHECK_RESULT("AudioOutputUnitStart");

    /* We're running! */
    return 1;
}


static int
COREAUDIO_OpenDevice(_THIS, const char *devname, int iscapture)
{
    AudioStreamBasicDescription strdesc;
    SDL_AudioFormat test_format = SDL_FirstAudioFormat(this->spec.format);
    int valid_datatype = 0;

    /* 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));

    /* Setup a AudioStreamBasicDescription with the requested format */
    memset(&strdesc, '\0', sizeof(AudioStreamBasicDescription));
    strdesc.mFormatID = kAudioFormatLinearPCM;
    strdesc.mFormatFlags = kLinearPCMFormatFlagIsPacked;
    strdesc.mChannelsPerFrame = this->spec.channels;
    strdesc.mSampleRate = this->spec.freq;
    strdesc.mFramesPerPacket = 1;

    while ((!valid_datatype) && (test_format)) {
        this->spec.format = test_format;
        /* Just a list of valid SDL formats, so people don't pass junk here. */
        switch (test_format) {
        case AUDIO_U8:
        case AUDIO_S8:
        case AUDIO_U16LSB:
        case AUDIO_S16LSB:
        case AUDIO_U16MSB:
        case AUDIO_S16MSB:
        case AUDIO_S32LSB:
        case AUDIO_S32MSB:
        case AUDIO_F32LSB:
        case AUDIO_F32MSB:
            valid_datatype = 1;
            strdesc.mBitsPerChannel = SDL_AUDIO_BITSIZE(this->spec.format);
            if (SDL_AUDIO_ISBIGENDIAN(this->spec.format))
                strdesc.mFormatFlags |= kLinearPCMFormatFlagIsBigEndian;

            if (SDL_AUDIO_ISFLOAT(this->spec.format))
                strdesc.mFormatFlags |= kLinearPCMFormatFlagIsFloat;
            else if (SDL_AUDIO_ISSIGNED(this->spec.format))
                strdesc.mFormatFlags |= kLinearPCMFormatFlagIsSignedInteger;
            break;
        }
    }

    if (!valid_datatype) {      /* shouldn't happen, but just in case... */
        SDL_SetError("Unsupported audio format");
        return 0;
    }

    strdesc.mBytesPerFrame =
        strdesc.mBitsPerChannel * strdesc.mChannelsPerFrame / 8;
    strdesc.mBytesPerPacket =
        strdesc.mBytesPerFrame * strdesc.mFramesPerPacket;

    if (!prepare_audiounit(this, devname, iscapture, &strdesc)) {
        return 0;  /* prepare_audiounit() will call SDL_SetError()... */
    }

    return 1;  /* good to go. */
}

/* vi: set ts=4 sw=4 expandtab: */