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+/*
+ * $Id: pa_unix_oss.c,v 1.1 2010/11/04 21:04:37 rbd Exp $
+ * PortAudio Portable Real-Time Audio Library
+ * Latest Version at: http://www.portaudio.com
+ * OSS implementation by:
+ * Douglas Repetto
+ * Phil Burk
+ * Dominic Mazzoni
+ * Arve Knudsen
+ *
+ * Based on the Open Source API proposed by Ross Bencina
+ * Copyright (c) 1999-2002 Ross Bencina, Phil Burk
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/*
+ * The text above constitutes the entire PortAudio license; however,
+ * the PortAudio community also makes the following non-binding requests:
+ *
+ * Any person wishing to distribute modifications to the Software is
+ * requested to send the modifications to the original developer so that
+ * they can be incorporated into the canonical version. It is also
+ * requested that these non-binding requests be included along with the
+ * license above.
+ */
+
+/**
+ @file
+ @ingroup hostapi_src
+*/
+
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/poll.h>
+#include <limits.h>
+#include <semaphore.h>
+
+#ifdef HAVE_SYS_SOUNDCARD_H
+# include <sys/soundcard.h>
+# define DEVICE_NAME_BASE "/dev/dsp"
+#elif defined(HAVE_LINUX_SOUNDCARD_H)
+# include <linux/soundcard.h>
+# define DEVICE_NAME_BASE "/dev/dsp"
+#elif defined(HAVE_MACHINE_SOUNDCARD_H)
+# include <machine/soundcard.h> /* JH20010905 */
+# define DEVICE_NAME_BASE "/dev/audio"
+#else
+# error No sound card header file
+#endif
+
+#include "portaudio.h"
+#include "pa_util.h"
+#include "pa_allocation.h"
+#include "pa_hostapi.h"
+#include "pa_stream.h"
+#include "pa_cpuload.h"
+#include "pa_process.h"
+#include "pa_unix_util.h"
+#include "pa_debugprint.h"
+
+static int sysErr_;
+static pthread_t mainThread_;
+
+/* Check return value of system call, and map it to PaError */
+#define ENSURE_(expr, code) \
+ do { \
+ if( UNLIKELY( (sysErr_ = (expr)) < 0 ) ) \
+ { \
+ /* PaUtil_SetLastHostErrorInfo should only be used in the main thread */ \
+ if( (code) == paUnanticipatedHostError && pthread_self() == mainThread_ ) \
+ { \
+ PaUtil_SetLastHostErrorInfo( paALSA, sysErr_, strerror( errno ) ); \
+ } \
+ \
+ PaUtil_DebugPrint(( "Expression '" #expr "' failed in '" __FILE__ "', line: " STRINGIZE( __LINE__ ) "\n" )); \
+ result = (code); \
+ goto error; \
+ } \
+ } while( 0 );
+
+#ifndef AFMT_S16_NE
+#define AFMT_S16_NE Get_AFMT_S16_NE()
+/*********************************************************************
+ * Some versions of OSS do not define AFMT_S16_NE. So check CPU.
+ * PowerPC is Big Endian. X86 is Little Endian.
+ */
+static int Get_AFMT_S16_NE( void )
+{
+ long testData = 1;
+ char *ptr = (char *) &testData;
+ int isLittle = ( *ptr == 1 ); /* Does address point to least significant byte? */
+ return isLittle ? AFMT_S16_LE : AFMT_S16_BE;
+}
+#endif
+
+/* PaOSSHostApiRepresentation - host api datastructure specific to this implementation */
+
+typedef struct
+{
+ PaUtilHostApiRepresentation inheritedHostApiRep;
+ PaUtilStreamInterface callbackStreamInterface;
+ PaUtilStreamInterface blockingStreamInterface;
+
+ PaUtilAllocationGroup *allocations;
+
+ PaHostApiIndex hostApiIndex;
+}
+PaOSSHostApiRepresentation;
+
+/** Per-direction structure for PaOssStream.
+ *
+ * Aspect StreamChannels: In case the user requests to open the same device for both capture and playback,
+ * but with different number of channels we will have to adapt between the number of user and host
+ * channels for at least one direction, since the configuration space is the same for both directions
+ * of an OSS device.
+ */
+typedef struct
+{
+ int fd;
+ const char *devName;
+ int userChannelCount, hostChannelCount;
+ int userInterleaved;
+ void *buffer;
+ PaSampleFormat userFormat, hostFormat;
+ double latency;
+ unsigned long hostFrames, numBufs;
+ void **userBuffers; /* For non-interleaved blocking */
+} PaOssStreamComponent;
+
+/** Implementation specific representation of a PaStream.
+ *
+ */
+typedef struct PaOssStream
+{
+ PaUtilStreamRepresentation streamRepresentation;
+ PaUtilCpuLoadMeasurer cpuLoadMeasurer;
+ PaUtilBufferProcessor bufferProcessor;
+
+ PaUtilThreading threading;
+
+ int sharedDevice;
+ unsigned long framesPerHostBuffer;
+ int triggered; /* Have the devices been triggered yet (first start) */
+
+ int isActive;
+ int isStopped;
+
+ int lastPosPtr;
+ double lastStreamBytes;
+
+ int framesProcessed;
+
+ double sampleRate;
+
+ int callbackMode;
+ int callbackStop, callbackAbort;
+
+ PaOssStreamComponent *capture, *playback;
+ unsigned long pollTimeout;
+ sem_t semaphore;
+}
+PaOssStream;
+
+typedef enum {
+ StreamMode_In,
+ StreamMode_Out
+} StreamMode;
+
+/* prototypes for functions declared in this file */
+
+static void Terminate( struct PaUtilHostApiRepresentation *hostApi );
+static PaError IsFormatSupported( struct PaUtilHostApiRepresentation *hostApi,
+ const PaStreamParameters *inputParameters,
+ const PaStreamParameters *outputParameters,
+ double sampleRate );
+static PaError OpenStream( struct PaUtilHostApiRepresentation *hostApi,
+ PaStream** s,
+ const PaStreamParameters *inputParameters,
+ const PaStreamParameters *outputParameters,
+ double sampleRate,
+ unsigned long framesPerBuffer,
+ PaStreamFlags streamFlags,
+ PaStreamCallback *streamCallback,
+ void *userData );
+static PaError CloseStream( PaStream* stream );
+static PaError StartStream( PaStream *stream );
+static PaError StopStream( PaStream *stream );
+static PaError AbortStream( PaStream *stream );
+static PaError IsStreamStopped( PaStream *s );
+static PaError IsStreamActive( PaStream *stream );
+static PaTime GetStreamTime( PaStream *stream );
+static double GetStreamCpuLoad( PaStream* stream );
+static PaError ReadStream( PaStream* stream, void *buffer, unsigned long frames );
+static PaError WriteStream( PaStream* stream, const void *buffer, unsigned long frames );
+static signed long GetStreamReadAvailable( PaStream* stream );
+static signed long GetStreamWriteAvailable( PaStream* stream );
+static PaError BuildDeviceList( PaOSSHostApiRepresentation *hostApi );
+
+
+/** Initialize the OSS API implementation.
+ *
+ * This function will initialize host API datastructures and query host devices for information.
+ *
+ * Aspect DeviceCapabilities: Enumeration of host API devices is initiated from here
+ *
+ * Aspect FreeResources: If an error is encountered under way we have to free each resource allocated in this function,
+ * this happens with the usual "error" label.
+ */
+PaError PaOSS_Initialize( PaUtilHostApiRepresentation **hostApi, PaHostApiIndex hostApiIndex )
+{
+ PaError result = paNoError;
+ PaOSSHostApiRepresentation *ossHostApi = NULL;
+
+ PA_UNLESS( ossHostApi = (PaOSSHostApiRepresentation*)PaUtil_AllocateMemory( sizeof(PaOSSHostApiRepresentation) ),
+ paInsufficientMemory );
+ PA_UNLESS( ossHostApi->allocations = PaUtil_CreateAllocationGroup(), paInsufficientMemory );
+ ossHostApi->hostApiIndex = hostApiIndex;
+
+ /* Initialize host API structure */
+ *hostApi = &ossHostApi->inheritedHostApiRep;
+ (*hostApi)->info.structVersion = 1;
+ (*hostApi)->info.type = paOSS;
+ (*hostApi)->info.name = "OSS";
+ (*hostApi)->Terminate = Terminate;
+ (*hostApi)->OpenStream = OpenStream;
+ (*hostApi)->IsFormatSupported = IsFormatSupported;
+
+ PA_ENSURE( BuildDeviceList( ossHostApi ) );
+
+ PaUtil_InitializeStreamInterface( &ossHostApi->callbackStreamInterface, CloseStream, StartStream,
+ StopStream, AbortStream, IsStreamStopped, IsStreamActive,
+ GetStreamTime, GetStreamCpuLoad,
+ PaUtil_DummyRead, PaUtil_DummyWrite,
+ PaUtil_DummyGetReadAvailable,
+ PaUtil_DummyGetWriteAvailable );
+
+ PaUtil_InitializeStreamInterface( &ossHostApi->blockingStreamInterface, CloseStream, StartStream,
+ StopStream, AbortStream, IsStreamStopped, IsStreamActive,
+ GetStreamTime, PaUtil_DummyGetCpuLoad,
+ ReadStream, WriteStream, GetStreamReadAvailable, GetStreamWriteAvailable );
+
+ mainThread_ = pthread_self();
+
+ return result;
+
+error:
+ if( ossHostApi )
+ {
+ if( ossHostApi->allocations )
+ {
+ PaUtil_FreeAllAllocations( ossHostApi->allocations );
+ PaUtil_DestroyAllocationGroup( ossHostApi->allocations );
+ }
+
+ PaUtil_FreeMemory( ossHostApi );
+ }
+ return result;
+}
+
+PaError PaUtil_InitializeDeviceInfo( PaDeviceInfo *deviceInfo, const char *name, PaHostApiIndex hostApiIndex, int maxInputChannels,
+ int maxOutputChannels, PaTime defaultLowInputLatency, PaTime defaultLowOutputLatency, PaTime defaultHighInputLatency,
+ PaTime defaultHighOutputLatency, double defaultSampleRate, PaUtilAllocationGroup *allocations )
+{
+ PaError result = paNoError;
+
+ deviceInfo->structVersion = 2;
+ if( allocations )
+ {
+ size_t len = strlen( name ) + 1;
+ PA_UNLESS( deviceInfo->name = PaUtil_GroupAllocateMemory( allocations, len ), paInsufficientMemory );
+ strncpy( (char *)deviceInfo->name, name, len );
+ }
+ else
+ deviceInfo->name = name;
+
+ deviceInfo->hostApi = hostApiIndex;
+ deviceInfo->maxInputChannels = maxInputChannels;
+ deviceInfo->maxOutputChannels = maxOutputChannels;
+ deviceInfo->defaultLowInputLatency = defaultLowInputLatency;
+ deviceInfo->defaultLowOutputLatency = defaultLowOutputLatency;
+ deviceInfo->defaultHighInputLatency = defaultHighInputLatency;
+ deviceInfo->defaultHighOutputLatency = defaultHighOutputLatency;
+ deviceInfo->defaultSampleRate = defaultSampleRate;
+
+error:
+ return result;
+}
+
+static PaError QueryDirection( const char *deviceName, StreamMode mode, double *defaultSampleRate, int *maxChannelCount,
+ double *defaultLowLatency, double *defaultHighLatency )
+{
+ PaError result = paNoError;
+ int numChannels, maxNumChannels;
+ int busy = 0;
+ int devHandle = -1;
+ int sr;
+ *maxChannelCount = 0; /* Default value in case this fails */
+
+ if ( (devHandle = open( deviceName, (mode == StreamMode_In ? O_RDONLY : O_WRONLY) | O_NONBLOCK )) < 0 )
+ {
+ if( errno == EBUSY || errno == EAGAIN )
+ {
+ PA_DEBUG(( "%s: Device %s busy\n", __FUNCTION__, deviceName ));
+ }
+ else
+ {
+ PA_DEBUG(( "%s: Can't access device: %s\n", __FUNCTION__, strerror( errno ) ));
+ }
+
+ return paDeviceUnavailable;
+ }
+
+ /* Negotiate for the maximum number of channels for this device. PLB20010927
+ * Consider up to 16 as the upper number of channels.
+ * Variable maxNumChannels should contain the actual upper limit after the call.
+ * Thanks to John Lazzaro and Heiko Purnhagen for suggestions.
+ */
+ maxNumChannels = 0;
+ for( numChannels = 1; numChannels <= 16; numChannels++ )
+ {
+ int temp = numChannels;
+ if( ioctl( devHandle, SNDCTL_DSP_CHANNELS, &temp ) < 0 )
+ {
+ busy = EAGAIN == errno || EBUSY == errno;
+ /* ioctl() failed so bail out if we already have stereo */
+ if( maxNumChannels >= 2 )
+ break;
+ }
+ else
+ {
+ /* ioctl() worked but bail out if it does not support numChannels.
+ * We don't want to leave gaps in the numChannels supported.
+ */
+ if( (numChannels > 2) && (temp != numChannels) )
+ break;
+ if( temp > maxNumChannels )
+ maxNumChannels = temp; /* Save maximum. */
+ }
+ }
+ /* A: We're able to open a device for capture if it's busy playing back and vice versa,
+ * but we can't configure anything */
+ if( 0 == maxNumChannels && busy )
+ {
+ result = paDeviceUnavailable;
+ goto error;
+ }
+
+ /* The above negotiation may fail for an old driver so try this older technique. */
+ if( maxNumChannels < 1 )
+ {
+ int stereo = 1;
+ if( ioctl( devHandle, SNDCTL_DSP_STEREO, &stereo ) < 0 )
+ {
+ maxNumChannels = 1;
+ }
+ else
+ {
+ maxNumChannels = (stereo) ? 2 : 1;
+ }
+ PA_DEBUG(( "%s: use SNDCTL_DSP_STEREO, maxNumChannels = %d\n", __FUNCTION__, maxNumChannels ));
+ }
+
+ /* During channel negotiation, the last ioctl() may have failed. This can
+ * also cause sample rate negotiation to fail. Hence the following, to return
+ * to a supported number of channels. SG20011005 */
+ {
+ /* use most reasonable default value */
+ int temp = PA_MIN( maxNumChannels, 2 );
+ ENSURE_( ioctl( devHandle, SNDCTL_DSP_CHANNELS, &temp ), paUnanticipatedHostError );
+ }
+
+ /* Get supported sample rate closest to 44100 Hz */
+ if( *defaultSampleRate < 0 )
+ {
+ sr = 44100;
+ if( ioctl( devHandle, SNDCTL_DSP_SPEED, &sr ) < 0 )
+ {
+ result = paUnanticipatedHostError;
+ goto error;
+ }
+
+ *defaultSampleRate = sr;
+ }
+
+ *maxChannelCount = maxNumChannels;
+ /* TODO */
+ *defaultLowLatency = 512. / *defaultSampleRate;
+ *defaultHighLatency = 2048. / *defaultSampleRate;
+
+error:
+ if( devHandle >= 0 )
+ close( devHandle );
+
+ return result;
+}
+
+/** Query OSS device.
+ *
+ * This is where PaDeviceInfo objects are constructed and filled in with relevant information.
+ *
+ * Aspect DeviceCapabilities: The inferred device capabilities are recorded in a PaDeviceInfo object that is constructed
+ * in place.
+ */
+static PaError QueryDevice( char *deviceName, PaOSSHostApiRepresentation *ossApi, PaDeviceInfo **deviceInfo )
+{
+ PaError result = paNoError;
+ double sampleRate = -1.;
+ int maxInputChannels, maxOutputChannels;
+ PaTime defaultLowInputLatency, defaultLowOutputLatency, defaultHighInputLatency, defaultHighOutputLatency;
+ PaError tmpRes = paNoError;
+ int busy = 0;
+ *deviceInfo = NULL;
+
+ /* douglas:
+ we have to do this querying in a slightly different order. apparently
+ some sound cards will give you different info based on their settins.
+ e.g. a card might give you stereo at 22kHz but only mono at 44kHz.
+ the correct order for OSS is: format, channels, sample rate
+ */
+
+ /* Aspect StreamChannels: The number of channels supported for a device may depend on the mode it is
+ * opened in, it may have more channels available for capture than playback and vice versa. Therefore
+ * we will open the device in both read- and write-only mode to determine the supported number.
+ */
+ if( (tmpRes = QueryDirection( deviceName, StreamMode_In, &sampleRate, &maxInputChannels, &defaultLowInputLatency,
+ &defaultHighInputLatency )) != paNoError )
+ {
+ if( tmpRes != paDeviceUnavailable )
+ {
+ PA_DEBUG(( "%s: Querying device %s for capture failed!\n", __FUNCTION__, deviceName ));
+ /* PA_ENSURE( tmpRes ); */
+ }
+ ++busy;
+ }
+ if( (tmpRes = QueryDirection( deviceName, StreamMode_Out, &sampleRate, &maxOutputChannels, &defaultLowOutputLatency,
+ &defaultHighOutputLatency )) != paNoError )
+ {
+ if( tmpRes != paDeviceUnavailable )
+ {
+ PA_DEBUG(( "%s: Querying device %s for playback failed!\n", __FUNCTION__, deviceName ));
+ /* PA_ENSURE( tmpRes ); */
+ }
+ ++busy;
+ }
+ assert( 0 <= busy && busy <= 2 );
+ if( 2 == busy ) /* Both directions are unavailable to us */
+ {
+ result = paDeviceUnavailable;
+ goto error;
+ }
+
+ PA_UNLESS( *deviceInfo = PaUtil_GroupAllocateMemory( ossApi->allocations, sizeof (PaDeviceInfo) ), paInsufficientMemory );
+ PA_ENSURE( PaUtil_InitializeDeviceInfo( *deviceInfo, deviceName, ossApi->hostApiIndex, maxInputChannels, maxOutputChannels,
+ defaultLowInputLatency, defaultLowOutputLatency, defaultHighInputLatency, defaultHighOutputLatency, sampleRate,
+ ossApi->allocations ) );
+
+error:
+ return result;
+}
+
+/** Query host devices.
+ *
+ * Loop over host devices and query their capabilitiesu
+ *
+ * Aspect DeviceCapabilities: This function calls QueryDevice on each device entry and receives a filled in PaDeviceInfo object
+ * per device, these are placed in the host api representation's deviceInfos array.
+ */
+static PaError BuildDeviceList( PaOSSHostApiRepresentation *ossApi )
+{
+ PaError result = paNoError;
+ PaUtilHostApiRepresentation *commonApi = &ossApi->inheritedHostApiRep;
+ int i;
+ int numDevices = 0, maxDeviceInfos = 1;
+ PaDeviceInfo **deviceInfos = NULL;
+
+ /* These two will be set to the first working input and output device, respectively */
+ commonApi->info.defaultInputDevice = paNoDevice;
+ commonApi->info.defaultOutputDevice = paNoDevice;
+
+ /* Find devices by calling QueryDevice on each
+ * potential device names. When we find a valid one,
+ * add it to a linked list.
+ * A: Set an arbitrary of 100 devices, should probably be a smarter way. */
+
+ for( i = 0; i < 100; i++ )
+ {
+ char deviceName[32];
+ PaDeviceInfo *deviceInfo;
+ int testResult;
+ struct stat stbuf;
+
+ if( i == 0 )
+ snprintf(deviceName, sizeof (deviceName), "%s", DEVICE_NAME_BASE);
+ else
+ snprintf(deviceName, sizeof (deviceName), "%s%d", DEVICE_NAME_BASE, i);
+
+ /* PA_DEBUG(("PaOSS BuildDeviceList: trying device %s\n", deviceName )); */
+ if( stat( deviceName, &stbuf ) < 0 )
+ {
+ if( ENOENT != errno )
+ PA_DEBUG(( "%s: Error stat'ing %s: %s\n", __FUNCTION__, deviceName, strerror( errno ) ));
+ continue;
+ }
+ if( (testResult = QueryDevice( deviceName, ossApi, &deviceInfo )) != paNoError )
+ {
+ if( testResult != paDeviceUnavailable )
+ PA_ENSURE( testResult );
+
+ continue;
+ }
+
+ ++numDevices;
+ if( !deviceInfos || numDevices > maxDeviceInfos )
+ {
+ maxDeviceInfos *= 2;
+ PA_UNLESS( deviceInfos = (PaDeviceInfo **) realloc( deviceInfos, maxDeviceInfos * sizeof (PaDeviceInfo *) ),
+ paInsufficientMemory );
+ }
+ {
+ int devIdx = numDevices - 1;
+ deviceInfos[devIdx] = deviceInfo;
+
+ if( commonApi->info.defaultInputDevice == paNoDevice && deviceInfo->maxInputChannels > 0 )
+ commonApi->info.defaultInputDevice = devIdx;
+ if( commonApi->info.defaultOutputDevice == paNoDevice && deviceInfo->maxOutputChannels > 0 )
+ commonApi->info.defaultOutputDevice = devIdx;
+ }
+ }
+
+ /* Make an array of PaDeviceInfo pointers out of the linked list */
+
+ PA_DEBUG(("PaOSS %s: Total number of devices found: %d\n", __FUNCTION__, numDevices));
+
+ commonApi->deviceInfos = (PaDeviceInfo**)PaUtil_GroupAllocateMemory(
+ ossApi->allocations, sizeof(PaDeviceInfo*) * numDevices );
+ memcpy( commonApi->deviceInfos, deviceInfos, numDevices * sizeof (PaDeviceInfo *) );
+
+ commonApi->info.deviceCount = numDevices;
+
+error:
+ free( deviceInfos );
+
+ return result;
+}
+
+static void Terminate( struct PaUtilHostApiRepresentation *hostApi )
+{
+ PaOSSHostApiRepresentation *ossHostApi = (PaOSSHostApiRepresentation*)hostApi;
+
+ if( ossHostApi->allocations )
+ {
+ PaUtil_FreeAllAllocations( ossHostApi->allocations );
+ PaUtil_DestroyAllocationGroup( ossHostApi->allocations );
+ }
+
+ PaUtil_FreeMemory( ossHostApi );
+}
+
+static PaError IsFormatSupported( struct PaUtilHostApiRepresentation *hostApi,
+ const PaStreamParameters *inputParameters,
+ const PaStreamParameters *outputParameters,
+ double sampleRate )
+{
+ PaError result = paNoError;
+ PaDeviceIndex device;
+ PaDeviceInfo *deviceInfo;
+ char *deviceName;
+ int inputChannelCount, outputChannelCount;
+ int tempDevHandle = -1;
+ int flags;
+ PaSampleFormat inputSampleFormat, outputSampleFormat;
+
+ if( inputParameters )
+ {
+ inputChannelCount = inputParameters->channelCount;
+ inputSampleFormat = inputParameters->sampleFormat;
+
+ /* unless alternate device specification is supported, reject the use of
+ paUseHostApiSpecificDeviceSpecification */
+
+ if( inputParameters->device == paUseHostApiSpecificDeviceSpecification )
+ return paInvalidDevice;
+
+ /* check that input device can support inputChannelCount */
+ if( inputChannelCount > hostApi->deviceInfos[ inputParameters->device ]->maxInputChannels )
+ return paInvalidChannelCount;
+
+ /* validate inputStreamInfo */
+ if( inputParameters->hostApiSpecificStreamInfo )
+ return paIncompatibleHostApiSpecificStreamInfo; /* this implementation doesn't use custom stream info */
+ }
+ else
+ {
+ inputChannelCount = 0;
+ }
+
+ if( outputParameters )
+ {
+ outputChannelCount = outputParameters->channelCount;
+ outputSampleFormat = outputParameters->sampleFormat;
+
+ /* unless alternate device specification is supported, reject the use of
+ paUseHostApiSpecificDeviceSpecification */
+
+ if( outputParameters->device == paUseHostApiSpecificDeviceSpecification )
+ return paInvalidDevice;
+
+ /* check that output device can support inputChannelCount */
+ if( outputChannelCount > hostApi->deviceInfos[ outputParameters->device ]->maxOutputChannels )
+ return paInvalidChannelCount;
+
+ /* validate outputStreamInfo */
+ if( outputParameters->hostApiSpecificStreamInfo )
+ return paIncompatibleHostApiSpecificStreamInfo; /* this implementation doesn't use custom stream info */
+ }
+ else
+ {
+ outputChannelCount = 0;
+ }
+
+ if (inputChannelCount == 0 && outputChannelCount == 0)
+ return paInvalidChannelCount;
+
+ /* if full duplex, make sure that they're the same device */
+
+ if (inputChannelCount > 0 && outputChannelCount > 0 &&
+ inputParameters->device != outputParameters->device)
+ return paInvalidDevice;
+
+ /* if full duplex, also make sure that they're the same number of channels */
+
+ if (inputChannelCount > 0 && outputChannelCount > 0 &&
+ inputChannelCount != outputChannelCount)
+ return paInvalidChannelCount;
+
+ /* open the device so we can do more tests */
+
+ if( inputChannelCount > 0 )
+ {
+ result = PaUtil_DeviceIndexToHostApiDeviceIndex(&device, inputParameters->device, hostApi);
+ if (result != paNoError)
+ return result;
+ }
+ else
+ {
+ result = PaUtil_DeviceIndexToHostApiDeviceIndex(&device, outputParameters->device, hostApi);
+ if (result != paNoError)
+ return result;
+ }
+
+ deviceInfo = hostApi->deviceInfos[device];
+ deviceName = (char *)deviceInfo->name;
+
+ flags = O_NONBLOCK;
+ if (inputChannelCount > 0 && outputChannelCount > 0)
+ flags |= O_RDWR;
+ else if (inputChannelCount > 0)
+ flags |= O_RDONLY;
+ else
+ flags |= O_WRONLY;
+
+ ENSURE_( tempDevHandle = open( deviceInfo->name, flags ), paDeviceUnavailable );
+
+ /* PaOssStream_Configure will do the rest of the checking for us */
+ /* PA_ENSURE( PaOssStream_Configure( tempDevHandle, deviceName, outputChannelCount, &sampleRate ) ); */
+
+ /* everything succeeded! */
+
+ error:
+ if( tempDevHandle >= 0 )
+ close( tempDevHandle );
+
+ return result;
+}
+
+/** Validate stream parameters.
+ *
+ * Aspect StreamChannels: We verify that the number of channels is within the allowed range for the device
+ */
+static PaError ValidateParameters( const PaStreamParameters *parameters, const PaDeviceInfo *deviceInfo, StreamMode mode )
+{
+ int maxChans;
+
+ assert( parameters );
+
+ if( parameters->device == paUseHostApiSpecificDeviceSpecification )
+ {
+ return paInvalidDevice;
+ }
+
+ maxChans = (mode == StreamMode_In ? deviceInfo->maxInputChannels :
+ deviceInfo->maxOutputChannels);
+ if( parameters->channelCount > maxChans )
+ {
+ return paInvalidChannelCount;
+ }
+
+ return paNoError;
+}
+
+static PaError PaOssStreamComponent_Initialize( PaOssStreamComponent *component, const PaStreamParameters *parameters,
+ int callbackMode, int fd, const char *deviceName )
+{
+ PaError result = paNoError;
+ assert( component );
+
+ memset( component, 0, sizeof (PaOssStreamComponent) );
+
+ component->fd = fd;
+ component->devName = deviceName;
+ component->userChannelCount = parameters->channelCount;
+ component->userFormat = parameters->sampleFormat;
+ component->latency = parameters->suggestedLatency;
+ component->userInterleaved = !(parameters->sampleFormat & paNonInterleaved);
+
+ if( !callbackMode && !component->userInterleaved )
+ {
+ /* Pre-allocate non-interleaved user provided buffers */
+ PA_UNLESS( component->userBuffers = PaUtil_AllocateMemory( sizeof (void *) * component->userChannelCount ),
+ paInsufficientMemory );
+ }
+
+error:
+ return result;
+}
+
+static void PaOssStreamComponent_Terminate( PaOssStreamComponent *component )
+{
+ assert( component );
+
+ if( component->fd >= 0 )
+ close( component->fd );
+ if( component->buffer )
+ PaUtil_FreeMemory( component->buffer );
+
+ if( component->userBuffers )
+ PaUtil_FreeMemory( component->userBuffers );
+
+ PaUtil_FreeMemory( component );
+}
+
+static PaError ModifyBlocking( int fd, int blocking )
+{
+ PaError result = paNoError;
+ int fflags;
+
+ ENSURE_( fflags = fcntl( fd, F_GETFL ), paUnanticipatedHostError );
+
+ if( blocking )
+ fflags &= ~O_NONBLOCK;
+ else
+ fflags |= O_NONBLOCK;
+
+ ENSURE_( fcntl( fd, F_SETFL, fflags ), paUnanticipatedHostError );
+
+error:
+ return result;
+}
+
+static PaError OpenDevices( const char *idevName, const char *odevName, int *idev, int *odev )
+{
+ PaError result = paNoError;
+ int flags = O_NONBLOCK, duplex = 0;
+ int enableBits = 0;
+ *idev = *odev = -1;
+
+ if( idevName && odevName )
+ {
+ duplex = 1;
+ flags |= O_RDWR;
+ }
+ else if( idevName )
+ flags |= O_RDONLY;
+ else
+ flags |= O_WRONLY;
+
+ /* open first in nonblocking mode, in case it's busy...
+ * A: then unset the non-blocking attribute */
+ assert( flags & O_NONBLOCK );
+ if( idevName )
+ {
+ ENSURE_( *idev = open( idevName, flags ), paDeviceUnavailable );
+ PA_ENSURE( ModifyBlocking( *idev, 1 ) ); /* Blocking */
+
+ /* Initially disable */
+ enableBits = ~PCM_ENABLE_INPUT;
+ ENSURE_( ioctl( *idev, SNDCTL_DSP_SETTRIGGER, &enableBits ), paUnanticipatedHostError );
+ }
+ if( odevName )
+ {
+ if( !idevName )
+ {
+ ENSURE_( *odev = open( odevName, flags ), paDeviceUnavailable );
+ PA_ENSURE( ModifyBlocking( *odev, 1 ) ); /* Blocking */
+
+ /* Initially disable */
+ enableBits = ~PCM_ENABLE_OUTPUT;
+ ENSURE_( ioctl( *odev, SNDCTL_DSP_SETTRIGGER, &enableBits ), paUnanticipatedHostError );
+ }
+ else
+ {
+ ENSURE_( *odev = dup( *idev ), paUnanticipatedHostError );
+ }
+ }
+
+error:
+ return result;
+}
+
+static PaError PaOssStream_Initialize( PaOssStream *stream, const PaStreamParameters *inputParameters, const PaStreamParameters *outputParameters,
+ PaStreamCallback callback, void *userData, PaStreamFlags streamFlags,
+ PaOSSHostApiRepresentation *ossApi )
+{
+ PaError result = paNoError;
+ int idev, odev;
+ PaUtilHostApiRepresentation *hostApi = &ossApi->inheritedHostApiRep;
+ const char *idevName = NULL, *odevName = NULL;
+
+ assert( stream );
+
+ memset( stream, 0, sizeof (PaOssStream) );
+ stream->isStopped = 1;
+
+ PA_ENSURE( PaUtil_InitializeThreading( &stream->threading ) );
+
+ if( inputParameters && outputParameters )
+ {
+ if( inputParameters->device == outputParameters->device )
+ stream->sharedDevice = 1;
+ }
+
+ if( inputParameters )
+ idevName = hostApi->deviceInfos[inputParameters->device]->name;
+ if( outputParameters )
+ odevName = hostApi->deviceInfos[outputParameters->device]->name;
+ PA_ENSURE( OpenDevices( idevName, odevName, &idev, &odev ) );
+ if( inputParameters )
+ {
+ PA_UNLESS( stream->capture = PaUtil_AllocateMemory( sizeof (PaOssStreamComponent) ), paInsufficientMemory );
+ PA_ENSURE( PaOssStreamComponent_Initialize( stream->capture, inputParameters, callback != NULL, idev, idevName ) );
+ }
+ if( outputParameters )
+ {
+ PA_UNLESS( stream->playback = PaUtil_AllocateMemory( sizeof (PaOssStreamComponent) ), paInsufficientMemory );
+ PA_ENSURE( PaOssStreamComponent_Initialize( stream->playback, outputParameters, callback != NULL, odev, odevName ) );
+ }
+
+ if( callback != NULL )
+ {
+ PaUtil_InitializeStreamRepresentation( &stream->streamRepresentation,
+ &ossApi->callbackStreamInterface, callback, userData );
+ stream->callbackMode = 1;
+ }
+ else
+ {
+ PaUtil_InitializeStreamRepresentation( &stream->streamRepresentation,
+ &ossApi->blockingStreamInterface, callback, userData );
+ }
+
+ ENSURE_( sem_init( &stream->semaphore, 0, 0 ), paInternalError );
+
+error:
+ return result;
+}
+
+static void PaOssStream_Terminate( PaOssStream *stream )
+{
+ assert( stream );
+
+ PaUtil_TerminateStreamRepresentation( &stream->streamRepresentation );
+ PaUtil_TerminateThreading( &stream->threading );
+
+ if( stream->capture )
+ PaOssStreamComponent_Terminate( stream->capture );
+ if( stream->playback )
+ PaOssStreamComponent_Terminate( stream->playback );
+
+ sem_destroy( &stream->semaphore );
+
+ PaUtil_FreeMemory( stream );
+}
+
+/** Translate from PA format to OSS native.
+ *
+ */
+static PaError Pa2OssFormat( PaSampleFormat paFormat, int *ossFormat )
+{
+ switch( paFormat )
+ {
+ case paUInt8:
+ *ossFormat = AFMT_U8;
+ break;
+ case paInt8:
+ *ossFormat = AFMT_S8;
+ break;
+ case paInt16:
+ *ossFormat = AFMT_S16_NE;
+ break;
+ default:
+ return paInternalError; /* This shouldn't happen */
+ }
+
+ return paNoError;
+}
+
+/** Return the PA-compatible formats that this device can support.
+ *
+ */
+static PaError GetAvailableFormats( PaOssStreamComponent *component, PaSampleFormat *availableFormats )
+{
+ PaError result = paNoError;
+ int mask = 0;
+ PaSampleFormat frmts = 0;
+
+ ENSURE_( ioctl( component->fd, SNDCTL_DSP_GETFMTS, &mask ), paUnanticipatedHostError );
+ if( mask & AFMT_U8 )
+ frmts |= paUInt8;
+ if( mask & AFMT_S8 )
+ frmts |= paInt8;
+ if( mask & AFMT_S16_NE )
+ frmts |= paInt16;
+ else
+ result = paSampleFormatNotSupported;
+
+ *availableFormats = frmts;
+
+error:
+ return result;
+}
+
+static unsigned int PaOssStreamComponent_FrameSize( PaOssStreamComponent *component )
+{
+ return Pa_GetSampleSize( component->hostFormat ) * component->hostChannelCount;
+}
+
+/** Buffer size in bytes.
+ *
+ */
+static unsigned long PaOssStreamComponent_BufferSize( PaOssStreamComponent *component )
+{
+ return PaOssStreamComponent_FrameSize( component ) * component->hostFrames * component->numBufs;
+}
+
+static int CalcHigherLogTwo( int n )
+{
+ int log2 = 0;
+ while( (1<<log2) < n ) log2++;
+ return log2;
+}
+
+static PaError PaOssStreamComponent_Configure( PaOssStreamComponent *component, double sampleRate, unsigned long
+ framesPerBuffer, StreamMode streamMode, PaOssStreamComponent *master )
+{
+ PaError result = paNoError;
+ int temp, nativeFormat;
+ int sr = (int)sampleRate;
+ PaSampleFormat availableFormats = 0, hostFormat = 0;
+ int chans = component->userChannelCount;
+ int frgmt;
+ int numBufs;
+ int bytesPerBuf;
+ unsigned long bufSz;
+ unsigned long fragSz;
+ audio_buf_info bufInfo;
+
+ /* We may have a situation where only one component (the master) is configured, if both point to the same device.
+ * In that case, the second component will copy settings from the other */
+ if( !master )
+ {
+ /* Aspect BufferSettings: If framesPerBuffer is unspecified we have to infer a suitable fragment size.
+ * The hardware need not respect the requested fragment size, so we may have to adapt.
+ */
+ if( framesPerBuffer == paFramesPerBufferUnspecified )
+ {
+ bufSz = (unsigned long)(component->latency * sampleRate);
+ fragSz = bufSz / 4;
+ }
+ else
+ {
+ fragSz = framesPerBuffer;
+ bufSz = (unsigned long)(component->latency * sampleRate) + fragSz; /* Latency + 1 buffer */
+ }
+
+ PA_ENSURE( GetAvailableFormats( component, &availableFormats ) );
+ hostFormat = PaUtil_SelectClosestAvailableFormat( availableFormats, component->userFormat );
+
+ /* OSS demands at least 2 buffers, and 16 bytes per buffer */
+ numBufs = (int)PA_MAX( bufSz / fragSz, 2 );
+ bytesPerBuf = PA_MAX( fragSz * Pa_GetSampleSize( hostFormat ) * chans, 16 );
+
+ /* The fragment parameters are encoded like this:
+ * Most significant byte: number of fragments
+ * Least significant byte: exponent of fragment size (i.e., for 256, 8)
+ */
+ frgmt = (numBufs << 16) + (CalcHigherLogTwo( bytesPerBuf ) & 0xffff);
+ ENSURE_( ioctl( component->fd, SNDCTL_DSP_SETFRAGMENT, &frgmt ), paUnanticipatedHostError );
+
+ /* A: according to the OSS programmer's guide parameters should be set in this order:
+ * format, channels, rate */
+
+ /* This format should be deemed good before we get this far */
+ PA_ENSURE( Pa2OssFormat( hostFormat, &temp ) );
+ nativeFormat = temp;
+ ENSURE_( ioctl( component->fd, SNDCTL_DSP_SETFMT, &temp ), paUnanticipatedHostError );
+ PA_UNLESS( temp == nativeFormat, paInternalError );
+
+ /* try to set the number of channels */
+ ENSURE_( ioctl( component->fd, SNDCTL_DSP_CHANNELS, &chans ), paSampleFormatNotSupported ); /* XXX: Should be paInvalidChannelCount? */
+ /* It's possible that the minimum number of host channels is greater than what the user requested */
+ PA_UNLESS( chans >= component->userChannelCount, paInvalidChannelCount );
+
+ /* try to set the sample rate */
+ ENSURE_( ioctl( component->fd, SNDCTL_DSP_SPEED, &sr ), paInvalidSampleRate );
+
+ /* reject if there's no sample rate within 1% of the one requested */
+ if( (fabs( sampleRate - sr ) / sampleRate) > 0.01 )
+ {
+ PA_DEBUG(("%s: Wanted %f, closest sample rate was %d\n", __FUNCTION__, sampleRate, sr ));
+ PA_ENSURE( paInvalidSampleRate );
+ }
+
+ ENSURE_( ioctl( component->fd, streamMode == StreamMode_In ? SNDCTL_DSP_GETISPACE : SNDCTL_DSP_GETOSPACE, &bufInfo ),
+ paUnanticipatedHostError );
+ component->numBufs = bufInfo.fragstotal;
+
+ /* This needs to be the last ioctl call before the first read/write, according to the OSS programmer's guide */
+ ENSURE_( ioctl( component->fd, SNDCTL_DSP_GETBLKSIZE, &bytesPerBuf ), paUnanticipatedHostError );
+
+ component->hostFrames = bytesPerBuf / Pa_GetSampleSize( hostFormat ) / chans;
+ component->hostChannelCount = chans;
+ component->hostFormat = hostFormat;
+ }
+ else
+ {
+ component->hostFormat = master->hostFormat;
+ component->hostFrames = master->hostFrames;
+ component->hostChannelCount = master->hostChannelCount;
+ component->numBufs = master->numBufs;
+ }
+
+ PA_UNLESS( component->buffer = PaUtil_AllocateMemory( PaOssStreamComponent_BufferSize( component ) ),
+ paInsufficientMemory );
+
+error:
+ return result;
+}
+
+static PaError PaOssStreamComponent_Read( PaOssStreamComponent *component, unsigned long *frames )
+{
+ PaError result = paNoError;
+ size_t len = *frames * PaOssStreamComponent_FrameSize( component );
+ ssize_t bytesRead;
+
+ ENSURE_( bytesRead = read( component->fd, component->buffer, len ), paUnanticipatedHostError );
+ *frames = bytesRead / PaOssStreamComponent_FrameSize( component );
+ /* TODO: Handle condition where number of frames read doesn't equal number of frames requested */
+
+error:
+ return result;
+}
+
+static PaError PaOssStreamComponent_Write( PaOssStreamComponent *component, unsigned long *frames )
+{
+ PaError result = paNoError;
+ size_t len = *frames * PaOssStreamComponent_FrameSize( component );
+ ssize_t bytesWritten;
+
+ ENSURE_( bytesWritten = write( component->fd, component->buffer, len ), paUnanticipatedHostError );
+ *frames = bytesWritten / PaOssStreamComponent_FrameSize( component );
+ /* TODO: Handle condition where number of frames written doesn't equal number of frames requested */
+
+error:
+ return result;
+}
+
+/** Configure the stream according to input/output parameters.
+ *
+ * Aspect StreamChannels: The minimum number of channels supported by the device may exceed that requested by
+ * the user, if so we'll record the actual number of host channels and adapt later.
+ */
+static PaError PaOssStream_Configure( PaOssStream *stream, double sampleRate, unsigned long framesPerBuffer,
+ double *inputLatency, double *outputLatency )
+{
+ PaError result = paNoError;
+ int duplex = stream->capture && stream->playback;
+ unsigned long framesPerHostBuffer = 0;
+
+ /* We should request full duplex first thing after opening the device */
+ if( duplex && stream->sharedDevice )
+ ENSURE_( ioctl( stream->capture->fd, SNDCTL_DSP_SETDUPLEX, 0 ), paUnanticipatedHostError );
+
+ if( stream->capture )
+ {
+ PaOssStreamComponent *component = stream->capture;
+ PA_ENSURE( PaOssStreamComponent_Configure( component, sampleRate, framesPerBuffer, StreamMode_In,
+ NULL ) );
+
+ assert( component->hostChannelCount > 0 );
+ assert( component->hostFrames > 0 );
+
+ *inputLatency = component->hostFrames * (component->numBufs - 1) / sampleRate;
+ }
+ if( stream->playback )
+ {
+ PaOssStreamComponent *component = stream->playback, *master = stream->sharedDevice ? stream->capture : NULL;
+ PA_ENSURE( PaOssStreamComponent_Configure( component, sampleRate, framesPerBuffer, StreamMode_Out,
+ master ) );
+
+ assert( component->hostChannelCount > 0 );
+ assert( component->hostFrames > 0 );
+
+ *outputLatency = component->hostFrames * (component->numBufs - 1) / sampleRate;
+ }
+
+ if( duplex )
+ framesPerHostBuffer = PA_MIN( stream->capture->hostFrames, stream->playback->hostFrames );
+ else if( stream->capture )
+ framesPerHostBuffer = stream->capture->hostFrames;
+ else if( stream->playback )
+ framesPerHostBuffer = stream->playback->hostFrames;
+
+ stream->framesPerHostBuffer = framesPerHostBuffer;
+ stream->pollTimeout = (int) ceil( 1e6 * framesPerHostBuffer / sampleRate ); /* Period in usecs, rounded up */
+
+ stream->sampleRate = stream->streamRepresentation.streamInfo.sampleRate = sampleRate;
+
+error:
+ return result;
+}
+
+/* see pa_hostapi.h for a list of validity guarantees made about OpenStream parameters */
+
+/** Open a PA OSS stream.
+ *
+ * Aspect StreamChannels: The number of channels is specified per direction (in/out), and can differ between the
+ * two. However, OSS doesn't support separate configuration spaces for capture and playback so if both
+ * directions are the same device we will demand the same number of channels. The number of channels can range
+ * from 1 to the maximum supported by the device.
+ *
+ * Aspect BufferSettings: If framesPerBuffer != paFramesPerBufferUnspecified the number of frames per callback
+ * must reflect this, in addition the host latency per device should approximate the corresponding
+ * suggestedLatency. Based on these constraints we need to determine a number of frames per host buffer that
+ * both capture and playback can agree on (they can be different devices), the buffer processor can adapt
+ * between host and user buffer size, but the ratio should preferably be integral.
+ */
+static PaError OpenStream( struct PaUtilHostApiRepresentation *hostApi,
+ PaStream** s,
+ const PaStreamParameters *inputParameters,
+ const PaStreamParameters *outputParameters,
+ double sampleRate,
+ unsigned long framesPerBuffer,
+ PaStreamFlags streamFlags,
+ PaStreamCallback *streamCallback,
+ void *userData )
+{
+ PaError result = paNoError;
+ PaOSSHostApiRepresentation *ossHostApi = (PaOSSHostApiRepresentation*)hostApi;
+ PaOssStream *stream = NULL;
+ int inputChannelCount = 0, outputChannelCount = 0;
+ PaSampleFormat inputSampleFormat = 0, outputSampleFormat = 0, inputHostFormat = 0, outputHostFormat = 0;
+ const PaDeviceInfo *inputDeviceInfo = 0, *outputDeviceInfo = 0;
+ int bpInitialized = 0;
+ double inLatency = 0., outLatency = 0.;
+ int i = 0;
+
+ /* validate platform specific flags */
+ if( (streamFlags & paPlatformSpecificFlags) != 0 )
+ return paInvalidFlag; /* unexpected platform specific flag */
+
+ if( inputParameters )
+ {
+ /* unless alternate device specification is supported, reject the use of
+ paUseHostApiSpecificDeviceSpecification */
+ inputDeviceInfo = hostApi->deviceInfos[inputParameters->device];
+ PA_ENSURE( ValidateParameters( inputParameters, inputDeviceInfo, StreamMode_In ) );
+
+ inputChannelCount = inputParameters->channelCount;
+ inputSampleFormat = inputParameters->sampleFormat;
+ }
+ if( outputParameters )
+ {
+ outputDeviceInfo = hostApi->deviceInfos[outputParameters->device];
+ PA_ENSURE( ValidateParameters( outputParameters, outputDeviceInfo, StreamMode_Out ) );
+
+ outputChannelCount = outputParameters->channelCount;
+ outputSampleFormat = outputParameters->sampleFormat;
+ }
+
+ /* Aspect StreamChannels: We currently demand that number of input and output channels are the same, if the same
+ * device is opened for both directions
+ */
+ if( inputChannelCount > 0 && outputChannelCount > 0 )
+ {
+ if( inputParameters->device == outputParameters->device )
+ {
+ if( inputParameters->channelCount != outputParameters->channelCount )
+ return paInvalidChannelCount;
+ }
+ }
+
+ /* Round framesPerBuffer to the next power-of-two to make OSS happy. */
+ if( framesPerBuffer != paFramesPerBufferUnspecified )
+ {
+ framesPerBuffer &= INT_MAX;
+ for (i = 1; framesPerBuffer > i; i <<= 1) ;
+ framesPerBuffer = i;
+ }
+
+ /* allocate and do basic initialization of the stream structure */
+ PA_UNLESS( stream = (PaOssStream*)PaUtil_AllocateMemory( sizeof(PaOssStream) ), paInsufficientMemory );
+ PA_ENSURE( PaOssStream_Initialize( stream, inputParameters, outputParameters, streamCallback, userData, streamFlags, ossHostApi ) );
+
+ PA_ENSURE( PaOssStream_Configure( stream, sampleRate, framesPerBuffer, &inLatency, &outLatency ) );
+
+ PaUtil_InitializeCpuLoadMeasurer( &stream->cpuLoadMeasurer, sampleRate );
+
+ if( inputParameters )
+ {
+ inputHostFormat = stream->capture->hostFormat;
+ stream->streamRepresentation.streamInfo.inputLatency = inLatency +
+ PaUtil_GetBufferProcessorInputLatency( &stream->bufferProcessor ) / sampleRate;
+ }
+ if( outputParameters )
+ {
+ outputHostFormat = stream->playback->hostFormat;
+ stream->streamRepresentation.streamInfo.outputLatency = outLatency +
+ PaUtil_GetBufferProcessorOutputLatency( &stream->bufferProcessor ) / sampleRate;
+ }
+
+ /* Initialize buffer processor with fixed host buffer size.
+ * Aspect StreamSampleFormat: Here we commit the user and host sample formats, PA infrastructure will
+ * convert between the two.
+ */
+ PA_ENSURE( PaUtil_InitializeBufferProcessor( &stream->bufferProcessor,
+ inputChannelCount, inputSampleFormat, inputHostFormat, outputChannelCount, outputSampleFormat,
+ outputHostFormat, sampleRate, streamFlags, framesPerBuffer, stream->framesPerHostBuffer,
+ paUtilFixedHostBufferSize, streamCallback, userData ) );
+ bpInitialized = 1;
+
+ *s = (PaStream*)stream;
+
+ return result;
+
+error:
+ if( bpInitialized )
+ PaUtil_TerminateBufferProcessor( &stream->bufferProcessor );
+ if( stream )
+ PaOssStream_Terminate( stream );
+
+ return result;
+}
+
+/*! Poll on I/O filedescriptors.
+
+ Poll till we've determined there's data for read or write. In the full-duplex case,
+ we don't want to hang around forever waiting for either input or output frames, so
+ whenever we have a timed out filedescriptor we check if we're nearing under/overrun
+ for the other direction (critical limit set at one buffer). If so, we exit the waiting
+ state, and go on with what we got. We align the number of frames on a host buffer
+ boundary because it is possible that the buffer size differs for the two directions and
+ the host buffer size is a compromise between the two.
+ */
+static PaError PaOssStream_WaitForFrames( PaOssStream *stream, unsigned long *frames )
+{
+ PaError result = paNoError;
+ int pollPlayback = 0, pollCapture = 0;
+ int captureAvail = INT_MAX, playbackAvail = INT_MAX, commonAvail;
+ audio_buf_info bufInfo;
+ /* int ofs = 0, nfds = stream->nfds; */
+ fd_set readFds, writeFds;
+ int nfds = 0;
+ struct timeval selectTimeval = {0, 0};
+ unsigned long timeout = stream->pollTimeout; /* In usecs */
+ int captureFd = -1, playbackFd = -1;
+
+ assert( stream );
+ assert( frames );
+
+ if( stream->capture )
+ {
+ pollCapture = 1;
+ captureFd = stream->capture->fd;
+ /* stream->capture->pfd->events = POLLIN; */
+ }
+ if( stream->playback )
+ {
+ pollPlayback = 1;
+ playbackFd = stream->playback->fd;
+ /* stream->playback->pfd->events = POLLOUT; */
+ }
+
+ FD_ZERO( &readFds );
+ FD_ZERO( &writeFds );
+
+ while( pollPlayback || pollCapture )
+ {
+ pthread_testcancel();
+
+ /* select may modify the timeout parameter */
+ selectTimeval.tv_usec = timeout;
+ nfds = 0;
+
+ if( pollCapture )
+ {
+ FD_SET( captureFd, &readFds );
+ nfds = captureFd + 1;
+ }
+ if( pollPlayback )
+ {
+ FD_SET( playbackFd, &writeFds );
+ nfds = PA_MAX( nfds, playbackFd + 1 );
+ }
+ ENSURE_( select( nfds, &readFds, &writeFds, NULL, &selectTimeval ), paUnanticipatedHostError );
+ /*
+ if( poll( stream->pfds + ofs, nfds, stream->pollTimeout ) < 0 )
+ {
+
+ ENSURE_( -1, paUnanticipatedHostError );
+ }
+ */
+ pthread_testcancel();
+
+ if( pollCapture )
+ {
+ if( FD_ISSET( captureFd, &readFds ) )
+ {
+ FD_CLR( captureFd, &readFds );
+ pollCapture = 0;
+ }
+ /*
+ if( stream->capture->pfd->revents & POLLIN )
+ {
+ --nfds;
+ ++ofs;
+ pollCapture = 0;
+ }
+ */
+ else if( stream->playback ) /* Timed out, go on with playback? */
+ {
+ /*PA_DEBUG(( "%s: Trying to poll again for capture frames, pollTimeout: %d\n",
+ __FUNCTION__, stream->pollTimeout ));*/
+ }
+ }
+ if( pollPlayback )
+ {
+ if( FD_ISSET( playbackFd, &writeFds ) )
+ {
+ FD_CLR( playbackFd, &writeFds );
+ pollPlayback = 0;
+ }
+ /*
+ if( stream->playback->pfd->revents & POLLOUT )
+ {
+ --nfds;
+ pollPlayback = 0;
+ }
+ */
+ else if( stream->capture ) /* Timed out, go on with capture? */
+ {
+ /*PA_DEBUG(( "%s: Trying to poll again for playback frames, pollTimeout: %d\n\n",
+ __FUNCTION__, stream->pollTimeout ));*/
+ }
+ }
+ }
+
+ if( stream->capture )
+ {
+ ENSURE_( ioctl( captureFd, SNDCTL_DSP_GETISPACE, &bufInfo ), paUnanticipatedHostError );
+ captureAvail = bufInfo.fragments * stream->capture->hostFrames;
+ if( !captureAvail )
+ PA_DEBUG(( "%s: captureAvail: 0\n", __FUNCTION__ ));
+
+ captureAvail = captureAvail == 0 ? INT_MAX : captureAvail; /* Disregard if zero */
+ }
+ if( stream->playback )
+ {
+ ENSURE_( ioctl( playbackFd, SNDCTL_DSP_GETOSPACE, &bufInfo ), paUnanticipatedHostError );
+ playbackAvail = bufInfo.fragments * stream->playback->hostFrames;
+ if( !playbackAvail )
+ {
+ PA_DEBUG(( "%s: playbackAvail: 0\n", __FUNCTION__ ));
+ }
+
+ playbackAvail = playbackAvail == 0 ? INT_MAX : playbackAvail; /* Disregard if zero */
+ }
+
+ commonAvail = PA_MIN( captureAvail, playbackAvail );
+ if( commonAvail == INT_MAX )
+ commonAvail = 0;
+ commonAvail -= commonAvail % stream->framesPerHostBuffer;
+
+ assert( commonAvail != INT_MAX );
+ assert( commonAvail >= 0 );
+ *frames = commonAvail;
+
+error:
+ return result;
+}
+
+/** Prepare stream for capture/playback.
+ *
+ * In order to synchronize capture and playback properly we use the SETTRIGGER command.
+ */
+static PaError PaOssStream_Prepare( PaOssStream *stream )
+{
+ PaError result = paNoError;
+ int enableBits = 0;
+
+ if( stream->triggered )
+ return result;
+
+ if( stream->playback )
+ {
+ size_t bufSz = PaOssStreamComponent_BufferSize( stream->playback );
+ memset( stream->playback->buffer, 0, bufSz );
+
+ /* Looks like we have to turn off blocking before we try this, but if we don't fill the buffer
+ * OSS will complain. */
+ PA_ENSURE( ModifyBlocking( stream->playback->fd, 0 ) );
+ while (1)
+ {
+ if( write( stream->playback->fd, stream->playback->buffer, bufSz ) < 0 )
+ break;
+ }
+ PA_ENSURE( ModifyBlocking( stream->playback->fd, 1 ) );
+ }
+
+ if( stream->sharedDevice )
+ {
+ enableBits = PCM_ENABLE_INPUT | PCM_ENABLE_OUTPUT;
+ ENSURE_( ioctl( stream->capture->fd, SNDCTL_DSP_SETTRIGGER, &enableBits ), paUnanticipatedHostError );
+ }
+ else
+ {
+ if( stream->capture )
+ {
+ enableBits = PCM_ENABLE_INPUT;
+ ENSURE_( ioctl( stream->capture->fd, SNDCTL_DSP_SETTRIGGER, &enableBits ), paUnanticipatedHostError );
+ }
+ if( stream->playback )
+ {
+ enableBits = PCM_ENABLE_OUTPUT;
+ ENSURE_( ioctl( stream->playback->fd, SNDCTL_DSP_SETTRIGGER, &enableBits ), paUnanticipatedHostError );
+ }
+ }
+
+ /* Ok, we have triggered the stream */
+ stream->triggered = 1;
+
+error:
+ return result;
+}
+
+/** Stop audio processing
+ *
+ */
+static PaError PaOssStream_Stop( PaOssStream *stream, int abort )
+{
+ PaError result = paNoError;
+
+ /* Looks like the only safe way to stop audio without reopening the device is SNDCTL_DSP_POST.
+ * Also disable capture/playback till the stream is started again */
+ if( stream->capture )
+ {
+ ENSURE_( ioctl( stream->capture->fd, SNDCTL_DSP_POST, 0 ), paUnanticipatedHostError );
+ }
+ if( stream->playback && !stream->sharedDevice )
+ {
+ ENSURE_( ioctl( stream->playback->fd, SNDCTL_DSP_POST, 0 ), paUnanticipatedHostError );
+ }
+
+error:
+ return result;
+}
+
+/** Clean up after thread exit.
+ *
+ * Aspect StreamState: If the user has registered a streamFinishedCallback it will be called here
+ */
+static void OnExit( void *data )
+{
+ PaOssStream *stream = (PaOssStream *) data;
+ assert( data );
+
+ PaUtil_ResetCpuLoadMeasurer( &stream->cpuLoadMeasurer );
+
+ PaOssStream_Stop( stream, stream->callbackAbort );
+
+ PA_DEBUG(( "OnExit: Stoppage\n" ));
+
+ /* Eventually notify user all buffers have played */
+ if( stream->streamRepresentation.streamFinishedCallback )
+ stream->streamRepresentation.streamFinishedCallback( stream->streamRepresentation.userData );
+
+ stream->callbackAbort = 0; /* Clear state */
+ stream->isActive = 0;
+}
+
+static PaError SetUpBuffers( PaOssStream *stream, unsigned long framesAvail )
+{
+ PaError result = paNoError;
+
+ if( stream->capture )
+ {
+ PaUtil_SetInterleavedInputChannels( &stream->bufferProcessor, 0, stream->capture->buffer,
+ stream->capture->hostChannelCount );
+ PaUtil_SetInputFrameCount( &stream->bufferProcessor, framesAvail );
+ }
+ if( stream->playback )
+ {
+ PaUtil_SetInterleavedOutputChannels( &stream->bufferProcessor, 0, stream->playback->buffer,
+ stream->playback->hostChannelCount );
+ PaUtil_SetOutputFrameCount( &stream->bufferProcessor, framesAvail );
+ }
+
+ return result;
+}
+
+/** Thread procedure for callback processing.
+ *
+ * Aspect StreamState: StartStream will wait on this to initiate audio processing, useful in case the
+ * callback should be used for buffer priming. When the stream is cancelled a separate function will
+ * take care of the transition to the Callback Finished state (the stream isn't considered Stopped
+ * before StopStream() or AbortStream() are called).
+ */
+static void *PaOSS_AudioThreadProc( void *userData )
+{
+ PaError result = paNoError;
+ PaOssStream *stream = (PaOssStream*)userData;
+ unsigned long framesAvail = 0, framesProcessed = 0;
+ int callbackResult = paContinue;
+ int triggered = stream->triggered; /* See if SNDCTL_DSP_TRIGGER has been issued already */
+ int initiateProcessing = triggered; /* Already triggered? */
+ PaStreamCallbackFlags cbFlags = 0; /* We might want to keep state across iterations */
+ PaStreamCallbackTimeInfo timeInfo = {0,0,0}; /* TODO: IMPLEMENT ME */
+
+ /*
+#if ( SOUND_VERSION > 0x030904 )
+ audio_errinfo errinfo;
+#endif
+*/
+
+ assert( stream );
+
+ pthread_cleanup_push( &OnExit, stream ); /* Execute OnExit when exiting */
+
+ /* The first time the stream is started we use SNDCTL_DSP_TRIGGER to accurately start capture and
+ * playback in sync, when the stream is restarted after being stopped we simply start by reading/
+ * writing.
+ */
+ PA_ENSURE( PaOssStream_Prepare( stream ) );
+
+ /* If we are to initiate processing implicitly by reading/writing data, we start off in blocking mode */
+ if( initiateProcessing )
+ {
+ /* Make sure devices are in blocking mode */
+ if( stream->capture )
+ ModifyBlocking( stream->capture->fd, 1 );
+ if( stream->playback )
+ ModifyBlocking( stream->playback->fd, 1 );
+ }
+
+ while( 1 )
+ {
+ pthread_testcancel();
+
+ if( stream->callbackStop && callbackResult == paContinue )
+ {
+ PA_DEBUG(( "Setting callbackResult to paComplete\n" ));
+ callbackResult = paComplete;
+ }
+
+ /* Aspect StreamState: Because of the messy OSS scheme we can't explicitly trigger device start unless
+ * the stream has been recently started, we will have to go right ahead and read/write in blocking
+ * fashion to trigger operation. Therefore we begin with processing one host buffer before we switch
+ * to non-blocking mode.
+ */
+ if( !initiateProcessing )
+ {
+ /* Wait on available frames */
+ PA_ENSURE( PaOssStream_WaitForFrames( stream, &framesAvail ) );
+ assert( framesAvail % stream->framesPerHostBuffer == 0 );
+ }
+ else
+ {
+ framesAvail = stream->framesPerHostBuffer;
+ }
+
+ while( framesAvail > 0 )
+ {
+ unsigned long frames = framesAvail;
+
+ pthread_testcancel();
+
+ PaUtil_BeginCpuLoadMeasurement( &stream->cpuLoadMeasurer );
+
+ /* Read data */
+ if ( stream->capture )
+ {
+ PA_ENSURE( PaOssStreamComponent_Read( stream->capture, &frames ) );
+ if( frames < framesAvail )
+ {
+ PA_DEBUG(( "Read %lu less frames than requested\n", framesAvail - frames ));
+ framesAvail = frames;
+ }
+ }
+
+#if ( SOUND_VERSION >= 0x030904 )
+ /*
+ Check with OSS to see if there have been any under/overruns
+ since last time we checked.
+ */
+ /*
+ if( ioctl( stream->deviceHandle, SNDCTL_DSP_GETERROR, &errinfo ) >= 0 )
+ {
+ if( errinfo.play_underruns )
+ cbFlags |= paOutputUnderflow ;
+ if( errinfo.record_underruns )
+ cbFlags |= paInputUnderflow ;
+ }
+ else
+ PA_DEBUG(( "SNDCTL_DSP_GETERROR command failed: %s\n", strerror( errno ) ));
+ */
+#endif
+
+ PaUtil_BeginBufferProcessing( &stream->bufferProcessor, &timeInfo,
+ cbFlags );
+ cbFlags = 0;
+ PA_ENSURE( SetUpBuffers( stream, framesAvail ) );
+
+ framesProcessed = PaUtil_EndBufferProcessing( &stream->bufferProcessor,
+ &callbackResult );
+ assert( framesProcessed == framesAvail );
+ PaUtil_EndCpuLoadMeasurement( &stream->cpuLoadMeasurer, framesProcessed );
+
+ if ( stream->playback )
+ {
+ frames = framesAvail;
+
+ PA_ENSURE( PaOssStreamComponent_Write( stream->playback, &frames ) );
+ if( frames < framesAvail )
+ {
+ /* TODO: handle bytesWritten != bytesRequested (slippage?) */
+ PA_DEBUG(( "Wrote %lu less frames than requested\n", framesAvail - frames ));
+ }
+ }
+
+ framesAvail -= framesProcessed;
+ stream->framesProcessed += framesProcessed;
+
+ if( callbackResult != paContinue )
+ break;
+ }
+
+ if( initiateProcessing || !triggered )
+ {
+ /* Non-blocking */
+ if( stream->capture )
+ PA_ENSURE( ModifyBlocking( stream->capture->fd, 0 ) );
+ if( stream->playback && !stream->sharedDevice )
+ PA_ENSURE( ModifyBlocking( stream->playback->fd, 0 ) );
+
+ initiateProcessing = 0;
+ sem_post( &stream->semaphore );
+ }
+
+ if( callbackResult != paContinue )
+ {
+ stream->callbackAbort = callbackResult == paAbort;
+ if( stream->callbackAbort || PaUtil_IsBufferProcessorOutputEmpty( &stream->bufferProcessor ) )
+ break;
+ }
+ }
+
+ pthread_cleanup_pop( 1 );
+
+error:
+ pthread_exit( NULL );
+}
+
+/** Close the stream.
+ *
+ */
+static PaError CloseStream( PaStream* s )
+{
+ PaError result = paNoError;
+ PaOssStream *stream = (PaOssStream*)s;
+
+ assert( stream );
+
+ PaUtil_TerminateBufferProcessor( &stream->bufferProcessor );
+ PaOssStream_Terminate( stream );
+
+ return result;
+}
+
+/** Start the stream.
+ *
+ * Aspect StreamState: After returning, the stream shall be in the Active state, implying that an eventual
+ * callback will be repeatedly called in a separate thread. If a separate thread is started this function
+ * will block untill it has started processing audio, otherwise audio processing is started directly.
+ */
+static PaError StartStream( PaStream *s )
+{
+ PaError result = paNoError;
+ PaOssStream *stream = (PaOssStream*)s;
+
+ stream->isActive = 1;
+ stream->isStopped = 0;
+ stream->lastPosPtr = 0;
+ stream->lastStreamBytes = 0;
+ stream->framesProcessed = 0;
+
+ /* only use the thread for callback streams */
+ if( stream->bufferProcessor.streamCallback )
+ {
+ PA_ENSURE( PaUtil_StartThreading( &stream->threading, &PaOSS_AudioThreadProc, stream ) );
+ sem_wait( &stream->semaphore );
+ }
+ else
+ PA_ENSURE( PaOssStream_Prepare( stream ) );
+
+error:
+ return result;
+}
+
+static PaError RealStop( PaOssStream *stream, int abort )
+{
+ PaError result = paNoError;
+
+ if( stream->callbackMode )
+ {
+ if( abort )
+ stream->callbackAbort = 1;
+ else
+ stream->callbackStop = 1;
+
+ PA_ENSURE( PaUtil_CancelThreading( &stream->threading, !abort, NULL ) );
+
+ stream->callbackStop = stream->callbackAbort = 0;
+ }
+ else
+ PA_ENSURE( PaOssStream_Stop( stream, abort ) );
+
+ stream->isStopped = 1;
+
+error:
+ return result;
+}
+
+/** Stop the stream.
+ *
+ * Aspect StreamState: This will cause the stream to transition to the Stopped state, playing all enqueued
+ * buffers.
+ */
+static PaError StopStream( PaStream *s )
+{
+ return RealStop( (PaOssStream *)s, 0 );
+}
+
+/** Abort the stream.
+ *
+ * Aspect StreamState: This will cause the stream to transition to the Stopped state, discarding all enqueued
+ * buffers. Note that the buffers are not currently correctly discarded, this is difficult without closing
+ * the OSS device.
+ */
+static PaError AbortStream( PaStream *s )
+{
+ return RealStop( (PaOssStream *)s, 1 );
+}
+
+/** Is the stream in the Stopped state.
+ *
+ */
+static PaError IsStreamStopped( PaStream *s )
+{
+ PaOssStream *stream = (PaOssStream*)s;
+
+ return (stream->isStopped);
+}
+
+/** Is the stream in the Active state.
+ *
+ */
+static PaError IsStreamActive( PaStream *s )
+{
+ PaOssStream *stream = (PaOssStream*)s;
+
+ return (stream->isActive);
+}
+
+static PaTime GetStreamTime( PaStream *s )
+{
+ PaOssStream *stream = (PaOssStream*)s;
+ count_info info;
+ int delta;
+
+ if( stream->playback ) {
+ if( ioctl( stream->playback->fd, SNDCTL_DSP_GETOPTR, &info) == 0 ) {
+ delta = ( info.bytes - stream->lastPosPtr ) /* & 0x000FFFFF*/;
+ return (float)(stream->lastStreamBytes + delta) / PaOssStreamComponent_FrameSize( stream->playback ) / stream->sampleRate;
+ }
+ }
+ else {
+ if (ioctl( stream->capture->fd, SNDCTL_DSP_GETIPTR, &info) == 0) {
+ delta = (info.bytes - stream->lastPosPtr) /*& 0x000FFFFF*/;
+ return (float)(stream->lastStreamBytes + delta) / PaOssStreamComponent_FrameSize( stream->capture ) / stream->sampleRate;
+ }
+ }
+
+ /* the ioctl failed, but we can still give a coarse estimate */
+
+ return stream->framesProcessed / stream->sampleRate;
+}
+
+
+static double GetStreamCpuLoad( PaStream* s )
+{
+ PaOssStream *stream = (PaOssStream*)s;
+
+ return PaUtil_GetCpuLoad( &stream->cpuLoadMeasurer );
+}
+
+
+/*
+ As separate stream interfaces are used for blocking and callback
+ streams, the following functions can be guaranteed to only be called
+ for blocking streams.
+*/
+
+
+static PaError ReadStream( PaStream* s,
+ void *buffer,
+ unsigned long frames )
+{
+ PaOssStream *stream = (PaOssStream*)s;
+ int bytesRequested, bytesRead;
+ unsigned long framesRequested;
+ void *userBuffer;
+
+ /* If user input is non-interleaved, PaUtil_CopyInput will manipulate the channel pointers,
+ * so we copy the user provided pointers */
+ if( stream->bufferProcessor.userInputIsInterleaved )
+ userBuffer = buffer;
+ else /* Copy channels into local array */
+ {
+ userBuffer = stream->capture->userBuffers;
+ memcpy( (void *)userBuffer, buffer, sizeof (void *) * stream->capture->userChannelCount );
+ }
+
+ while( frames )
+ {
+ framesRequested = PA_MIN( frames, stream->capture->hostFrames );
+
+ bytesRequested = framesRequested * PaOssStreamComponent_FrameSize( stream->capture );
+ bytesRead = read( stream->capture->fd, stream->capture->buffer, bytesRequested );
+ if ( bytesRequested != bytesRead )
+ return paUnanticipatedHostError;
+
+ PaUtil_SetInputFrameCount( &stream->bufferProcessor, stream->capture->hostFrames );
+ PaUtil_SetInterleavedInputChannels( &stream->bufferProcessor, 0, stream->capture->buffer, stream->capture->hostChannelCount );
+ PaUtil_CopyInput( &stream->bufferProcessor, &userBuffer, framesRequested );
+ frames -= framesRequested;
+ }
+ return paNoError;
+}
+
+
+static PaError WriteStream( PaStream *s, const void *buffer, unsigned long frames )
+{
+ PaOssStream *stream = (PaOssStream*)s;
+ int bytesRequested, bytesWritten;
+ unsigned long framesConverted;
+ const void *userBuffer;
+
+ /* If user output is non-interleaved, PaUtil_CopyOutput will manipulate the channel pointers,
+ * so we copy the user provided pointers */
+ if( stream->bufferProcessor.userOutputIsInterleaved )
+ userBuffer = buffer;
+ else
+ {
+ /* Copy channels into local array */
+ userBuffer = stream->playback->userBuffers;
+ memcpy( (void *)userBuffer, buffer, sizeof (void *) * stream->playback->userChannelCount );
+ }
+
+ while( frames )
+ {
+ PaUtil_SetOutputFrameCount( &stream->bufferProcessor, stream->playback->hostFrames );
+ PaUtil_SetInterleavedOutputChannels( &stream->bufferProcessor, 0, stream->playback->buffer, stream->playback->hostChannelCount );
+
+ framesConverted = PaUtil_CopyOutput( &stream->bufferProcessor, &userBuffer, frames );
+ frames -= framesConverted;
+
+ bytesRequested = framesConverted * PaOssStreamComponent_FrameSize( stream->playback );
+ bytesWritten = write( stream->playback->fd, stream->playback->buffer, bytesRequested );
+
+ if ( bytesRequested != bytesWritten )
+ return paUnanticipatedHostError;
+ }
+ return paNoError;
+}
+
+
+static signed long GetStreamReadAvailable( PaStream* s )
+{
+ PaOssStream *stream = (PaOssStream*)s;
+ audio_buf_info info;
+
+ if( ioctl( stream->capture->fd, SNDCTL_DSP_GETISPACE, &info ) < 0 )
+ return paUnanticipatedHostError;
+ return info.fragments * stream->capture->hostFrames;
+}
+
+
+/* TODO: Compute number of allocated bytes somewhere else, can we use ODELAY with capture */
+static signed long GetStreamWriteAvailable( PaStream* s )
+{
+ PaOssStream *stream = (PaOssStream*)s;
+ int delay = 0;
+
+ if( ioctl( stream->playback->fd, SNDCTL_DSP_GETODELAY, &delay ) < 0 )
+ return paUnanticipatedHostError;
+
+ return (PaOssStreamComponent_BufferSize( stream->playback ) - delay) / PaOssStreamComponent_FrameSize( stream->playback );
+}
+