pa_linux_pulseaudio_internal.h

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/*
 * PulseAudio host to play natively in Linux based systems without
 * ALSA emulation
 *
 * Copyright (c) 2014-2023 Tuukka Pasanen <tuukka.pasanen@ilmi.fi>
 * Copyright (c) 2016 Sqweek
 *
 * 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.
 */

#ifndef _PA_HOSTAPI_PULSEAUDIO_H_
#define _PA_HOSTAPI_PULSEAUDIO_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_ringbuffer.h"
#include "pa_debugprint.h"

/* PulseAudio headers */
#include <stdio.h>
#include <string.h>
#include <pulse/pulseaudio.h>

#ifdef __cplusplus
extern "C"
{
#endif                          /* __cplusplus */

/* prototypes for functions declared in this file */

#define PA_PULSEAUDIO_SET_LAST_HOST_ERROR(errorCode, errorText) \
    PaUtil_SetLastHostErrorInfo(paInDevelopment, errorCode, errorText)

#define PAPULSEAUDIO_MAX_DEVICECOUNT 1024
#define PAPULSEAUDIO_MAX_DEVICENAME 1024

/* Default latency values to expose. Chosen by trial and error to be reasonable. */
#define PA_PULSEAUDIO_DEFAULT_MIN_LATENCY 0.010
#define PA_PULSEAUDIO_DEFAULT_MAX_LATENCY 0.080

/* Just some value that Pulseaudio can handle */
#define PAPULSEAUDIO_FRAMESPERBUFFERUNSPEC 32

/* Assuming of 2 seconds of 44100 Hz sample rate with FLOAT (4 bytes) and stereo channels (2 channels).
   You should have pretty good size buffer with this. If output/intput doesn't happens in 2 second we
   have more trouble than this buffer.
   @todo change this to something more sophisticated */
#define PULSEAUDIO_BUFFER_SIZE (96100 * 4 * 2)

typedef struct
{
    PaUtilHostApiRepresentation inheritedHostApiRep;
    PaUtilStreamInterface callbackStreamInterface;
    PaUtilStreamInterface blockingStreamInterface;

    PaUtilAllocationGroup *allocations;

    PaHostApiIndex hostApiIndex;
    PaDeviceInfo deviceInfoArray[PAPULSEAUDIO_MAX_DEVICECOUNT];
    char *pulseaudioDeviceNames[PAPULSEAUDIO_MAX_DEVICECOUNT];
    pa_sample_spec pulseaudioDefaultSampleSpec;

    /* PulseAudio stuff goes here */
    pa_threaded_mainloop *mainloop;
    pa_mainloop_api *mainloopApi;
    pa_context *context;
    int deviceCount;
    pa_time_event *timeEvent;
}
PaPulseAudio_HostApiRepresentation;

/* PaPulseAudio_Stream - a stream data structure specifically for this implementation */

typedef struct PaPulseAudio_Stream
{
    PaUtilStreamRepresentation streamRepresentation;
    PaUtilCpuLoadMeasurer cpuLoadMeasurer;
    PaUtilBufferProcessor bufferProcessor;
    PaPulseAudio_HostApiRepresentation *hostapi;

    unsigned long framesPerHostCallback;
    pa_threaded_mainloop *mainloop;
    pa_context *context;
    pa_sample_spec outputSampleSpec;
    pa_sample_spec inputSampleSpec;
    pa_stream *outputStream;
    pa_stream *inputStream;
    pa_buffer_attr outputBufferAttr;
    pa_buffer_attr inputBufferAttr;
    unsigned int suggestedLatencyUSecs;
    int outputUnderflows;
    int outputChannelCount;
    int inputChannelCount;

    size_t maxFramesPerBuffer;
    size_t maxFramesHostPerBuffer;
    int outputFrameSize;
    int inputFrameSize;

    PaDeviceIndex inputDevice;
    PaDeviceIndex outputDevice;

    char *outputStreamName;
    char *inputStreamName;

    PaUtilRingBuffer inputRing;

    size_t missedBytes;

    /* Used in communication between threads
     *
     * State machine works like this:
     * When stream is wanted to start with Pa_StartStream
     * then isActive is 1 if opening of devices goes well
     * and isStopped is then 0.
     *
     * When requested to stop isStopped is 1 on isActive is 0
     * and nothing should be written to ouput or read from input
     * anymore
     *
     * Pulseaudio does not like this as it creates streams and they
     * start when they are ready and it can be after we have
     * exited Pa_StartStream or before if get's kicked up very fast
     *
     * pulseaudioIsActive and pulseaudioIsStopped are used to find if
     * there is stream active or stopped in pulseaudio side. They
     * live their own life besides isActive and isStopped to make sure
     * that portaudio will have input and output available before
     * reading or writing to stream.
     */
    volatile sig_atomic_t isActive;
    volatile sig_atomic_t isStopped;
    volatile sig_atomic_t pulseaudioIsActive;
    volatile sig_atomic_t pulseaudioIsStopped;

}
PaPulseAudio_Stream;

/* PulseAudio Error checking macro */
#define PA_PULSEAUDIO_IS_ERROR(pastream, errorCode) \
    if( !(pastream) || \
        !(pastream)->context || \
        !PA_CONTEXT_IS_GOOD( pa_context_get_state( (pastream)->context ) ) || \
        ( (pastream)->outputStream && \
        !PA_STREAM_IS_GOOD( pa_stream_get_state( (pastream)->outputStream ) ) ) || \
        ( (pastream)->inputStream && \
        !PA_STREAM_IS_GOOD( pa_stream_get_state( (pastream)->inputStream ) ) ) ) \
    { \
        if( !(pastream) || \
            ( (pastream)->context && \
              pa_context_get_state( (pastream)->context ) == PA_CONTEXT_FAILED ) || \
            ( (pastream)->outputStream && \
              pa_stream_get_state( (pastream)->outputStream ) == PA_STREAM_FAILED ) || \
            ( (pastream)->inputStream && \
               pa_stream_get_state( (pastream)->inputStream ) == PA_STREAM_FAILED ) ) \
            { \
                return errorCode; \
            } \
    } \
    if( !(pastream)->isActive || (pastream)->isStopped ) \
    { \
        return paStreamIsStopped; \
    }

void PaPulseAudio_ReleaseOperation(PaPulseAudio_HostApiRepresentation *hostapi,
                                  pa_operation **pulseaudioOperation);

void PaPulseAudio_Lock( pa_threaded_mainloop *mainloop );

void PaPulseAudio_UnLock( pa_threaded_mainloop *mainloop );

PaError PaPulseAudio_Initialize( PaUtilHostApiRepresentation ** hostApi,
                                 PaHostApiIndex index );

void Terminate( struct PaUtilHostApiRepresentation *hostApi );


PaError IsFormatSupported( struct PaUtilHostApiRepresentation *hostApi,
                           const PaStreamParameters * inputParameters,
                           const PaStreamParameters * outputParameters,
                           double sampleRate );

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 IsStreamStopped( PaStream * s );
PaError IsStreamActive( PaStream * stream );

PaTime GetStreamTime( PaStream * stream );
double GetStreamCpuLoad( PaStream * stream );

PaPulseAudio_HostApiRepresentation *PaPulseAudio_New( void );
void PaPulseAudio_Free( PaPulseAudio_HostApiRepresentation * ptr );

int PaPulseAudio_CheckConnection( PaPulseAudio_HostApiRepresentation * ptr );

void PaPulseAudio_CheckContextStateCb( pa_context * c,
                                       void *userdata );
void PaPulseAudio_ServerInfoCb( pa_context *c,
                                const pa_server_info *i,
                                void *userdata );

void PaPulseAudio_SinkListCb( pa_context * c,
                              const pa_sink_info * l,
                              int eol,
                              void *userdata );

void PaPulseAudio_SourceListCb( pa_context * c,
                                const pa_source_info * l,
                                int eol,
                                void *userdata );

void PaPulseAudio_StreamStateCb( pa_stream * s,
                                 void *userdata );

void PaPulseAudio_StreamStartedCb( pa_stream * s,
                                   void *userdata );

void PaPulseAudio_StreamUnderflowCb( pa_stream * s,
                                     void *userdata );

PaError PaPulseAudio_ConvertPortaudioFormatToPaPulseAudio_( PaSampleFormat portaudiosf,
                                                            pa_sample_spec * pulseaudiosf
);

#ifdef __cplusplus
}
#endif                          /* __cplusplus */


#endif