/** @file patest_buffer.c	@ingroup test_src	@brief Test opening streams with different buffer sizes.	@author Phil Burk  http://www.softsynth.com*//* * $Id: patest_buffer.c 1097 2006-08-26 08:27:53Z rossb $ * * This program uses the PortAudio Portable Audio Library. * For more information see: http://www.portaudio.com * Copyright (c) 1999-2000 Ross Bencina and 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. */#include <stdio.h>#include <stdlib.h>#include <math.h>#include "portaudio.h"#define NUM_SECONDS   (3)#define SAMPLE_RATE   (44100)#ifndef M_PI#define M_PI  (3.14159265)#endif#define TABLE_SIZE   (200)#define BUFFER_TABLE  14long buffer_table[] = {paFramesPerBufferUnspecified,16,32,64,128,200,256,500,512,600,723,1000,1024,2345};typedef struct{    short sine[TABLE_SIZE];    int left_phase;    int right_phase;    unsigned int sampsToGo;}paTestData;PaError TestOnce( int buffersize, PaDeviceIndex );/* This routine will be called by the PortAudio engine when audio is needed.** It may called at interrupt level on some machines so don't do anything** that could mess up the system like calling malloc() or free().*/static int patest1Callback( const void *inputBuffer, void *outputBuffer,                            unsigned long framesPerBuffer,                            const PaStreamCallbackTimeInfo* timeInfo,                            PaStreamCallbackFlags statusFlags,                            void *userData ){    paTestData *data = (paTestData*)userData;    short *out = (short*)outputBuffer;    unsigned int i;    int finished = 0;    (void) inputBuffer; /* Prevent "unused variable" warnings. */    if( data->sampsToGo < framesPerBuffer )    {        /* final buffer... */        for( i=0; i<data->sampsToGo; i++ )        {            *out++ = data->sine[data->left_phase];  /* left */            *out++ = data->sine[data->right_phase];  /* right */            data->left_phase += 1;            if( data->left_phase >= TABLE_SIZE ) data->left_phase -= TABLE_SIZE;            data->right_phase += 3; /* higher pitch so we can distinguish left and right. */            if( data->right_phase >= TABLE_SIZE ) data->right_phase -= TABLE_SIZE;        }        /* zero remainder of final buffer */        for( ; i<framesPerBuffer; i++ )        {            *out++ = 0; /* left */            *out++ = 0; /* right */        }        finished = 1;    }    else    {        for( i=0; i<framesPerBuffer; i++ )        {            *out++ = data->sine[data->left_phase];  /* left */            *out++ = data->sine[data->right_phase];  /* right */            data->left_phase += 1;            if( data->left_phase >= TABLE_SIZE ) data->left_phase -= TABLE_SIZE;            data->right_phase += 3; /* higher pitch so we can distinguish left and right. */            if( data->right_phase >= TABLE_SIZE ) data->right_phase -= TABLE_SIZE;        }        data->sampsToGo -= framesPerBuffer;    }    return finished;}/*******************************************************************/int main(int argc, char **args);int main(int argc, char **args){    int i;    int device = -1;    PaError err;    printf("Test opening streams with different buffer sizes\n");    if( argc > 1 ) {       device=atoi( args[1] );       printf("Using device number %d.\n\n", device );    } else {       printf("Using default device.\n\n" );    }    for (i = 0 ; i < BUFFER_TABLE; i++)    {        printf("Buffer size %ld\n", buffer_table[i]);        err = TestOnce(buffer_table[i], device);        if( err < 0 ) return 0;    }    return 0;}PaError TestOnce( int buffersize, PaDeviceIndex device ){    PaStreamParameters outputParameters;    PaStream *stream;    PaError err;    paTestData data;    int i;    int totalSamps;    /* initialise sinusoidal wavetable */    for( i=0; i<TABLE_SIZE; i++ )    {        data.sine[i] = (short) (32767.0 * sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. ));    }    data.left_phase = data.right_phase = 0;    data.sampsToGo = totalSamps =  NUM_SECONDS * SAMPLE_RATE; /* Play for a few seconds. */    err = Pa_Initialize();    if( err != paNoError ) goto error;        if( device == -1 )        outputParameters.device = Pa_GetDefaultOutputDevice(); /* default output device */    else        outputParameters.device = device ;    outputParameters.channelCount = 2;                      /* stereo output */    outputParameters.sampleFormat = paInt16;                /* 32 bit floating point output */    outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;    outputParameters.hostApiSpecificStreamInfo = NULL;    err = Pa_OpenStream(              &stream,              NULL,                         /* no input */              &outputParameters,              SAMPLE_RATE,              buffersize,                   /* frames per buffer */              (paClipOff | paDitherOff),              patest1Callback,              &data );    if( err != paNoError ) goto error;    err = Pa_StartStream( stream );    if( err != paNoError ) goto error;    printf("Waiting for sound to finish.\n");    Pa_Sleep(1000*NUM_SECONDS);    err = Pa_CloseStream( stream );    if( err != paNoError ) goto error;    Pa_Terminate();    return paNoError;error:    Pa_Terminate();    fprintf( stderr, "An error occured while using the portaudio stream\n" );    fprintf( stderr, "Error number: %d\n", err );    fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );    fprintf( stderr, "Host Error message: %s\n", Pa_GetLastHostErrorInfo()->errorText );    return err;}