The Tor Browser: media/libcubeb/src/cubeb_audiounit.c@44a2da4a2ab2 (annotated)

media/libcubeb/src/cubeb_audiounit.c@44a2da4a2ab2 (annotated)

media/libcubeb/src/cubeb_audiounit.c

Fri, 16 Jan 2015 04:50:19 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Fri, 16 Jan 2015 04:50:19 +0100
branch: TOR_BUG_9701
changeset 13: 44a2da4a2ab2
permissions: -rw-r--r--

Replace accessor implementation with direct member state manipulation, by
request https://trac.torproject.org/projects/tor/ticket/9701#comment:32

 /*
  * Copyright © 2011 Mozilla Foundation
  *
  * This program is made available under an ISC-style license.  See the
  * accompanying file LICENSE for details.
  */
 #undef NDEBUG
 #include <assert.h>
 #include <pthread.h>
 #include <stdlib.h>
 #include <AudioUnit/AudioUnit.h>
 #include <CoreAudio/AudioHardware.h>
 #include <CoreAudio/HostTime.h>
 #include <CoreFoundation/CoreFoundation.h>
 #include "cubeb/cubeb.h"
 #include "cubeb-internal.h"
 #if !defined(kCFCoreFoundationVersionNumber10_7)
 /* From CoreFoundation CFBase.h */
 #define kCFCoreFoundationVersionNumber10_7 635.00
 #endif
 #define CUBEB_STREAM_MAX 16
 #define NBUFS 4
 static struct cubeb_ops const audiounit_ops;
 struct cubeb {
   struct cubeb_ops const * ops;
   pthread_mutex_t mutex;
   int active_streams;
   int limit_streams;
 };
 struct cubeb_stream {
   cubeb * context;
   AudioUnit unit;
   cubeb_data_callback data_callback;
   cubeb_state_callback state_callback;
   void * user_ptr;
   AudioStreamBasicDescription sample_spec;
   pthread_mutex_t mutex;
   uint64_t frames_played;
   uint64_t frames_queued;
   int shutdown;
   int draining;
   uint64_t current_latency_frames;
   uint64_t hw_latency_frames;
 };
 static int64_t
 audiotimestamp_to_latency(AudioTimeStamp const * tstamp, cubeb_stream * stream)
 {
   if (!(tstamp->mFlags & kAudioTimeStampHostTimeValid)) {
     return 0;
   }
   uint64_t pres = AudioConvertHostTimeToNanos(tstamp->mHostTime);
   uint64_t now = AudioConvertHostTimeToNanos(AudioGetCurrentHostTime());
   return ((pres - now) * stream->sample_spec.mSampleRate) / 1000000000LL;
 }
 static OSStatus
 audiounit_output_callback(void * user_ptr, AudioUnitRenderActionFlags * flags,
                           AudioTimeStamp const * tstamp, UInt32 bus, UInt32 nframes,
                           AudioBufferList * bufs)
 {
   cubeb_stream * stm;
   unsigned char * buf;
   long got;
   OSStatus r;
   assert(bufs->mNumberBuffers == 1);
   buf = bufs->mBuffers[0].mData;
   stm = user_ptr;
   pthread_mutex_lock(&stm->mutex);
   stm->current_latency_frames = audiotimestamp_to_latency(tstamp, stm);
   if (stm->draining || stm->shutdown) {
     pthread_mutex_unlock(&stm->mutex);
     if (stm->draining) {
       r = AudioOutputUnitStop(stm->unit);
       assert(r == 0);
       stm->state_callback(stm, stm->user_ptr, CUBEB_STATE_DRAINED);
     }
     return noErr;
   }
   pthread_mutex_unlock(&stm->mutex);
   got = stm->data_callback(stm, stm->user_ptr, buf, nframes);
   pthread_mutex_lock(&stm->mutex);
   if (got < 0) {
     /* XXX handle this case. */
     assert(false);
     pthread_mutex_unlock(&stm->mutex);
     return noErr;
   }
   if ((UInt32) got < nframes) {
     size_t got_bytes = got * stm->sample_spec.mBytesPerFrame;
     size_t rem_bytes = (nframes - got) * stm->sample_spec.mBytesPerFrame;
     stm->draining = 1;
     memset(buf + got_bytes, 0, rem_bytes);
   }
   stm->frames_played = stm->frames_queued;
   stm->frames_queued += got;
   pthread_mutex_unlock(&stm->mutex);
   return noErr;
 }
 /*static*/ int
 audiounit_init(cubeb ** context, char const * context_name)
 {
   cubeb * ctx;
   int r;
   *context = NULL;
   ctx = calloc(1, sizeof(*ctx));
   assert(ctx);
   ctx->ops = &audiounit_ops;
   r = pthread_mutex_init(&ctx->mutex, NULL);
   assert(r == 0);
   ctx->active_streams = 0;
   ctx->limit_streams = kCFCoreFoundationVersionNumber < kCFCoreFoundationVersionNumber10_7;
   *context = ctx;
   return CUBEB_OK;
 }
 static char const *
 audiounit_get_backend_id(cubeb * ctx)
 {
   return "audiounit";
 }
 static int
 audiounit_get_output_device_id(AudioDeviceID * device_id)
 {
   UInt32 size;
   OSStatus r;
   AudioObjectPropertyAddress output_device_address = {
     kAudioHardwarePropertyDefaultOutputDevice,
     kAudioObjectPropertyScopeGlobal,
     kAudioObjectPropertyElementMaster
   };
   size = sizeof(*device_id);
   r = AudioObjectGetPropertyData(kAudioObjectSystemObject,
                                  &output_device_address,
 ,
                                  NULL,
                                  &size,
                                  device_id);
   if (r != noErr) {
     return CUBEB_ERROR;
   }
   return CUBEB_OK;
 }
 /* Get the acceptable buffer size (in frames) that this device can work with. */
 static int
 audiounit_get_acceptable_latency_range(AudioValueRange * latency_range)
 {
   UInt32 size;
   OSStatus r;
   AudioDeviceID output_device_id;
   AudioObjectPropertyAddress output_device_buffer_size_range = {
     kAudioDevicePropertyBufferFrameSizeRange,
     kAudioDevicePropertyScopeOutput,
     kAudioObjectPropertyElementMaster
   };
   if (audiounit_get_output_device_id(&output_device_id) != CUBEB_OK) {
     return CUBEB_ERROR;
   }
   /* Get the buffer size range this device supports */
   size = sizeof(*latency_range);
   r = AudioObjectGetPropertyData(output_device_id,
                                  &output_device_buffer_size_range,
 ,
                                  NULL,
                                  &size,
                                  latency_range);
   if (r != noErr) {
     return CUBEB_ERROR;
   }
   return CUBEB_OK;
 }
 int
 audiounit_get_max_channel_count(cubeb * ctx, uint32_t * max_channels)
 {
   UInt32 size;
   OSStatus r;
   AudioDeviceID output_device_id;
   AudioStreamBasicDescription stream_format;
   AudioObjectPropertyAddress stream_format_address = {
     kAudioDevicePropertyStreamFormat,
     kAudioDevicePropertyScopeOutput,
     kAudioObjectPropertyElementMaster
   };
   assert(ctx && max_channels);
   if (audiounit_get_output_device_id(&output_device_id) != CUBEB_OK) {
     return CUBEB_ERROR;
   }
   size = sizeof(stream_format);
   r = AudioObjectGetPropertyData(output_device_id,
                                  &stream_format_address,
 ,
                                  NULL,
                                  &size,
                                  &stream_format);
   if (r != noErr) {
     return CUBEB_ERROR;
   }
   *max_channels = stream_format.mChannelsPerFrame;
   return CUBEB_OK;
 }
 static int
 audiounit_get_min_latency(cubeb * ctx, cubeb_stream_params params, uint32_t * latency_ms)
 {
   AudioValueRange latency_range;
   if (audiounit_get_acceptable_latency_range(&latency_range) != CUBEB_OK) {
     return CUBEB_ERROR;
   }
   *latency_ms = (latency_range.mMinimum * 1000 + params.rate - 1) / params.rate;
   return CUBEB_OK;
 }
 static int
 audiounit_get_preferred_sample_rate(cubeb * ctx, uint32_t * rate)
 {
   UInt32 size;
   OSStatus r;
   Float64 fsamplerate;
   AudioDeviceID output_device_id;
   AudioObjectPropertyAddress samplerate_address = {
     kAudioDevicePropertyNominalSampleRate,
     kAudioObjectPropertyScopeGlobal,
     kAudioObjectPropertyElementMaster
   };
   if (audiounit_get_output_device_id(&output_device_id) != CUBEB_OK) {
     return CUBEB_ERROR;
   }
   size = sizeof(fsamplerate);
   r = AudioObjectGetPropertyData(output_device_id,
                                  &samplerate_address,
 ,
                                  NULL,
                                  &size,
                                  &fsamplerate);
   if (r != noErr) {
     return CUBEB_ERROR;
   }
   *rate = (uint32_t)fsamplerate;
   return CUBEB_OK;
 }
 static void
 audiounit_destroy(cubeb * ctx)
 {
   int r;
   assert(ctx->active_streams == 0);
   r = pthread_mutex_destroy(&ctx->mutex);
   assert(r == 0);
   free(ctx);
 }
 static void audiounit_stream_destroy(cubeb_stream * stm);
 static int
 audiounit_stream_init(cubeb * context, cubeb_stream ** stream, char const * stream_name,
                       cubeb_stream_params stream_params, unsigned int latency,
                       cubeb_data_callback data_callback, cubeb_state_callback state_callback,
                       void * user_ptr)
 {
   AudioStreamBasicDescription ss;
 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1060
   ComponentDescription desc;
   Component comp;
 #else
   AudioComponentDescription desc;
   AudioComponent comp;
 #endif
   cubeb_stream * stm;
   AURenderCallbackStruct input;
   unsigned int buffer_size, default_buffer_size;
   OSStatus r;
   UInt32 size;
   AudioDeviceID output_device_id;
   AudioValueRange latency_range;
   assert(context);
   *stream = NULL;
   memset(&ss, 0, sizeof(ss));
   ss.mFormatFlags = 0;
   switch (stream_params.format) {
   case CUBEB_SAMPLE_S16LE:
     ss.mBitsPerChannel = 16;
     ss.mFormatFlags |= kAudioFormatFlagIsSignedInteger;
     break;
   case CUBEB_SAMPLE_S16BE:
     ss.mBitsPerChannel = 16;
     ss.mFormatFlags |= kAudioFormatFlagIsSignedInteger |
                        kAudioFormatFlagIsBigEndian;
     break;
   case CUBEB_SAMPLE_FLOAT32LE:
     ss.mBitsPerChannel = 32;
     ss.mFormatFlags |= kAudioFormatFlagIsFloat;
     break;
   case CUBEB_SAMPLE_FLOAT32BE:
     ss.mBitsPerChannel = 32;
     ss.mFormatFlags |= kAudioFormatFlagIsFloat |
                        kAudioFormatFlagIsBigEndian;
     break;
   default:
     return CUBEB_ERROR_INVALID_FORMAT;
   }
   ss.mFormatID = kAudioFormatLinearPCM;
   ss.mFormatFlags |= kLinearPCMFormatFlagIsPacked;
   ss.mSampleRate = stream_params.rate;
   ss.mChannelsPerFrame = stream_params.channels;
   ss.mBytesPerFrame = (ss.mBitsPerChannel / 8) * ss.mChannelsPerFrame;
   ss.mFramesPerPacket = 1;
   ss.mBytesPerPacket = ss.mBytesPerFrame * ss.mFramesPerPacket;
   pthread_mutex_lock(&context->mutex);
   if (context->limit_streams && context->active_streams >= CUBEB_STREAM_MAX) {
     pthread_mutex_unlock(&context->mutex);
     return CUBEB_ERROR;
   }
   context->active_streams += 1;
   pthread_mutex_unlock(&context->mutex);
   desc.componentType = kAudioUnitType_Output;
   desc.componentSubType = kAudioUnitSubType_DefaultOutput;
   desc.componentManufacturer = kAudioUnitManufacturer_Apple;
   desc.componentFlags = 0;
   desc.componentFlagsMask = 0;
 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1060
   comp = FindNextComponent(NULL, &desc);
 #else
   comp = AudioComponentFindNext(NULL, &desc);
 #endif
   assert(comp);
   stm = calloc(1, sizeof(*stm));
   assert(stm);
   stm->context = context;
   stm->data_callback = data_callback;
   stm->state_callback = state_callback;
   stm->user_ptr = user_ptr;
   stm->sample_spec = ss;
   r = pthread_mutex_init(&stm->mutex, NULL);
   assert(r == 0);
   stm->frames_played = 0;
   stm->frames_queued = 0;
   stm->current_latency_frames = 0;
   stm->hw_latency_frames = UINT64_MAX;
 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1060
   r = OpenAComponent(comp, &stm->unit);
 #else
   r = AudioComponentInstanceNew(comp, &stm->unit);
 #endif
   if (r != 0) {
     audiounit_stream_destroy(stm);
     return CUBEB_ERROR;
   }
   input.inputProc = audiounit_output_callback;
   input.inputProcRefCon = stm;
   r = AudioUnitSetProperty(stm->unit, kAudioUnitProperty_SetRenderCallback,
                            kAudioUnitScope_Global, 0, &input, sizeof(input));
   if (r != 0) {
     audiounit_stream_destroy(stm);
     return CUBEB_ERROR;
   }
   buffer_size = latency / 1000.0 * ss.mSampleRate;
   /* Get the range of latency this particular device can work with, and clamp
    * the requested latency to this acceptable range. */
   if (audiounit_get_acceptable_latency_range(&latency_range) != CUBEB_OK) {
     audiounit_stream_destroy(stm);
     return CUBEB_ERROR;
   }
   if (buffer_size < (unsigned int) latency_range.mMinimum) {
     buffer_size = (unsigned int) latency_range.mMinimum;
   } else if (buffer_size > (unsigned int) latency_range.mMaximum) {
     buffer_size = (unsigned int) latency_range.mMaximum;
   }
   /**
    * Get the default buffer size. If our latency request is below the default,
    * set it. Otherwise, use the default latency.
    **/
   size = sizeof(default_buffer_size);
   r = AudioUnitGetProperty(stm->unit, kAudioDevicePropertyBufferFrameSize,
                            kAudioUnitScope_Output, 0, &default_buffer_size, &size);
   if (r != 0) {
     audiounit_stream_destroy(stm);
     return CUBEB_ERROR;
   }
   // Setting the latency doesn't work well for USB headsets (eg. plantronics).
   // Keep the default latency for now.
 #if 0
   if (buffer_size < default_buffer_size) {
     /* Set the maximum number of frame that the render callback will ask for,
      * effectively setting the latency of the stream. This is process-wide. */
     r = AudioUnitSetProperty(stm->unit, kAudioDevicePropertyBufferFrameSize,
                              kAudioUnitScope_Output, 0, &buffer_size, sizeof(buffer_size));
     if (r != 0) {
       audiounit_stream_destroy(stm);
       return CUBEB_ERROR;
     }
   }
 #endif
   r = AudioUnitSetProperty(stm->unit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input,
 , &ss, sizeof(ss));
   if (r != 0) {
     audiounit_stream_destroy(stm);
     return CUBEB_ERROR;
   }
   r = AudioUnitInitialize(stm->unit);
   if (r != 0) {
     audiounit_stream_destroy(stm);
     return CUBEB_ERROR;
   }
   *stream = stm;
   return CUBEB_OK;
 }
 static void
 audiounit_stream_destroy(cubeb_stream * stm)
 {
   int r;
   stm->shutdown = 1;
   if (stm->unit) {
     AudioOutputUnitStop(stm->unit);
     AudioUnitUninitialize(stm->unit);
 #if MAC_OS_X_VERSION_MIN_REQUIRED < 1060
     CloseComponent(stm->unit);
 #else
     AudioComponentInstanceDispose(stm->unit);
 #endif
   }
   r = pthread_mutex_destroy(&stm->mutex);
   assert(r == 0);
   pthread_mutex_lock(&stm->context->mutex);
   assert(stm->context->active_streams >= 1);
   stm->context->active_streams -= 1;
   pthread_mutex_unlock(&stm->context->mutex);
   free(stm);
 }
 static int
 audiounit_stream_start(cubeb_stream * stm)
 {
   OSStatus r;
   r = AudioOutputUnitStart(stm->unit);
   assert(r == 0);
   stm->state_callback(stm, stm->user_ptr, CUBEB_STATE_STARTED);
   return CUBEB_OK;
 }
 static int
 audiounit_stream_stop(cubeb_stream * stm)
 {
   OSStatus r;
   r = AudioOutputUnitStop(stm->unit);
   assert(r == 0);
   stm->state_callback(stm, stm->user_ptr, CUBEB_STATE_STOPPED);
   return CUBEB_OK;
 }
 static int
 audiounit_stream_get_position(cubeb_stream * stm, uint64_t * position)
 {
   pthread_mutex_lock(&stm->mutex);
   *position = stm->frames_played;
   pthread_mutex_unlock(&stm->mutex);
   return CUBEB_OK;
 }
 int
 audiounit_stream_get_latency(cubeb_stream * stm, uint32_t * latency)
 {
   pthread_mutex_lock(&stm->mutex);
   if (stm->hw_latency_frames == UINT64_MAX) {
     UInt32 size;
     uint32_t device_latency_frames, device_safety_offset;
     double unit_latency_sec;
     AudioDeviceID output_device_id;
     OSStatus r;
     AudioObjectPropertyAddress latency_address = {
       kAudioDevicePropertyLatency,
       kAudioDevicePropertyScopeOutput,
       kAudioObjectPropertyElementMaster
     };
     AudioObjectPropertyAddress safety_offset_address = {
       kAudioDevicePropertySafetyOffset,
       kAudioDevicePropertyScopeOutput,
       kAudioObjectPropertyElementMaster
     };
     r = audiounit_get_output_device_id(&output_device_id);
     if (r != noErr) {
       pthread_mutex_unlock(&stm->mutex);
       return CUBEB_ERROR;
     }
     size = sizeof(unit_latency_sec);
     r = AudioUnitGetProperty(stm->unit,
                              kAudioUnitProperty_Latency,
                              kAudioUnitScope_Global,
 ,
                              &unit_latency_sec,
                              &size);
     if (r != noErr) {
       pthread_mutex_unlock(&stm->mutex);
       return CUBEB_ERROR;
     }
     size = sizeof(device_latency_frames);
     r = AudioObjectGetPropertyData(output_device_id,
                                    &latency_address,
 ,
                                    NULL,
                                    &size,
                                    &device_latency_frames);
     if (r != noErr) {
       pthread_mutex_unlock(&stm->mutex);
       return CUBEB_ERROR;
     }
     size = sizeof(device_safety_offset);
     r = AudioObjectGetPropertyData(output_device_id,
                                    &safety_offset_address,
 ,
                                    NULL,
                                    &size,
                                    &device_safety_offset);
     if (r != noErr) {
       pthread_mutex_unlock(&stm->mutex);
       return CUBEB_ERROR;
     }
     /* This part is fixed and depend on the stream parameter and the hardware. */
     stm->hw_latency_frames =
       (uint32_t)(unit_latency_sec * stm->sample_spec.mSampleRate)
       + device_latency_frames
       + device_safety_offset;
   }
   *latency = stm->hw_latency_frames + stm->current_latency_frames;
   pthread_mutex_unlock(&stm->mutex);
   return CUBEB_OK;
 }
 static struct cubeb_ops const audiounit_ops = {
   .init = audiounit_init,
   .get_backend_id = audiounit_get_backend_id,
   .get_max_channel_count = audiounit_get_max_channel_count,
   .get_min_latency = audiounit_get_min_latency,
   .get_preferred_sample_rate = audiounit_get_preferred_sample_rate,
   .destroy = audiounit_destroy,
   .stream_init = audiounit_stream_init,
   .stream_destroy = audiounit_stream_destroy,
   .stream_start = audiounit_stream_start,
   .stream_stop = audiounit_stream_stop,
   .stream_get_position = audiounit_stream_get_position,
   .stream_get_latency = audiounit_stream_get_latency
 };

The Tor Browser / annotate

media/libcubeb/src/cubeb_audiounit.c@44a2da4a2ab2 (annotated)

media/libcubeb/src/cubeb_audiounit.c