pa_unix_util.c

一个开源的sip源代码

/*
 * $Id: pa_unix_util.c 1182 2007-03-16 19:48:30Z aknudsen $
 * Portable Audio I/O Library
 * UNIX platform-specific support functions
 *
 * Based on the Open Source API proposed by Ross Bencina
 * Copyright (c) 1999-2000 Ross Bencina
 *
 * 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 unix_src
*/
 
#include <pthread.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>
#include <sys/time.h>
#include <assert.h>
#include <string.h> /* For memset */
#include <math.h>
#include <errno.h>

#include "pa_util.h"
#include "pa_unix_util.h"

/*
   Track memory allocations to avoid leaks.
 */

#if PA_TRACK_MEMORY
static int numAllocations_ = 0;
#endif


void *PaUtil_AllocateMemory( long size )
{
    void *result = malloc( size );

#if PA_TRACK_MEMORY
    if( result != NULL ) numAllocations_ += 1;
#endif
    return result;
}


void PaUtil_FreeMemory( void *block )
{
    if( block != NULL )
    {
        free( block );
#if PA_TRACK_MEMORY
        numAllocations_ -= 1;
#endif

    }
}


int PaUtil_CountCurrentlyAllocatedBlocks( void )
{
#if PA_TRACK_MEMORY
    return numAllocations_;
#else
    return 0;
#endif
}


void Pa_Sleep( long msec )
{
#ifdef HAVE_NANOSLEEP
    struct timespec req = {0}, rem = {0};
    PaTime time = msec / 1.e3;
    req.tv_sec = (time_t)time;
    assert(time - req.tv_sec < 1.0);
    req.tv_nsec = (long)((time - req.tv_sec) * 1.e9);
    nanosleep(&req, &rem);
    /* XXX: Try sleeping the remaining time (contained in rem) if interrupted by a signal? */
#else
    while( msec > 999 )     /* For OpenBSD and IRIX, argument */
        {                   /* to usleep must be < 1000000.   */
        usleep( 999000 );
        msec -= 999;
        }
    usleep( msec * 1000 );
#endif
}

/*            *** NOT USED YET: ***
static int usePerformanceCounter_;
static double microsecondsPerTick_;
*/

void PaUtil_InitializeClock( void )
{
    /* TODO */
}


PaTime PaUtil_GetTime( void )
{
#ifdef HAVE_CLOCK_GETTIME
    struct timespec tp;
    clock_gettime(CLOCK_REALTIME, &tp);
    return (PaTime)(tp.tv_sec + tp.tv_nsec / 1.e9);
#else
    struct timeval tv;
    gettimeofday( &tv, NULL );
    return (PaTime) tv.tv_usec / 1000000. + tv.tv_sec;
#endif
}

PaError PaUtil_InitializeThreading( PaUtilThreading *threading )
{
    (void) paUtilErr_;
    return paNoError;
}

void PaUtil_TerminateThreading( PaUtilThreading *threading )
{
}

PaError PaUtil_StartThreading( PaUtilThreading *threading, void *(*threadRoutine)(void *), void *data )
{
    pthread_create( &threading->callbackThread, NULL, threadRoutine, data );
    return paNoError;
}

PaError PaUtil_CancelThreading( PaUtilThreading *threading, int wait, PaError *exitResult )
{
    PaError result = paNoError;
    void *pret;

    if( exitResult )
        *exitResult = paNoError;

    /* Only kill the thread if it isn't in the process of stopping (flushing adaptation buffers) */
    if( !wait )
        pthread_cancel( threading->callbackThread );   /* XXX: Safe to call this if the thread has exited on its own? */
    pthread_join( threading->callbackThread, &pret );

#ifdef PTHREAD_CANCELED
    if( pret && PTHREAD_CANCELED != pret )
#else
    /* !wait means the thread may have been canceled */
    if( pret && wait )
#endif
    {
        if( exitResult )
            *exitResult = *(PaError *) pret;
        free( pret );
    }

    return result;
}

/* Threading */
/* paUnixMainThread 
 * We have to be a bit careful with defining this global variable,
 * as explained below. */
#ifdef __apple__
/* apple/gcc has a "problem" with global vars and dynamic libs.
   Initializing it seems to fix the problem.
   Described a bit in this thread:
   http://gcc.gnu.org/ml/gcc/2005-06/msg00179.html
*/
pthread_t paUnixMainThread = 0;
#else
/*pthreads are opaque. We don't know that asigning it an int value
  always makes sense, so we don't initialize it unless we have to.*/
pthread_t paUnixMainThread = 0;
#endif

PaError PaUnixThreading_Initialize()
{
    paUnixMainThread = pthread_self();
    return paNoError;
}

static PaError BoostPriority( PaUnixThread* self )
{
    PaError result = paNoError;
    struct sched_param spm = { 0 };
    /* Priority should only matter between contending FIFO threads? */
    spm.sched_priority = 1;

    assert( self );

    if( pthread_setschedparam( self->thread, SCHED_FIFO, &spm ) != 0 )
    {
        PA_UNLESS( errno == EPERM, paInternalError );  /* Lack permission to raise priority */
        PA_DEBUG(( "Failed bumping priority\n" ));
        result = 0;
    }
    else
    {
        result = 1; /* Success */
    }
error:
    return result;
}

PaError PaUnixThread_New( PaUnixThread* self, void* (*threadFunc)( void* ), void* threadArg, PaTime waitForChild,
        int rtSched )
{
    PaError result = paNoError;
    pthread_attr_t attr;
    int started = 0;

    memset( self, 0, sizeof (PaUnixThread) );
    PaUnixMutex_Initialize( &self->mtx );
    PA_ASSERT_CALL( pthread_cond_init( &self->cond, NULL ), 0 );

    self->parentWaiting = 0 != waitForChild;

    /* Spawn thread */

/* Temporarily disabled since we should test during configuration for presence of required mman.h header */
#if 0
#if defined _POSIX_MEMLOCK && (_POSIX_MEMLOCK != -1)
    if( rtSched )
    {
        if( mlockall( MCL_CURRENT | MCL_FUTURE ) < 0 )
        {
            int savedErrno = errno;             /* In case errno gets overwritten */
            assert( savedErrno != EINVAL );     /* Most likely a programmer error */
            PA_UNLESS( (savedErrno == EPERM), paInternalError );
            PA_DEBUG(( "%s: Failed locking memory\n", __FUNCTION__ ));
        }
        else
            PA_DEBUG(( "%s: Successfully locked memory\n", __FUNCTION__ ));
    }
#endif
#endif

    PA_UNLESS( !pthread_attr_init( &attr ), paInternalError );
    /* Priority relative to other processes */
    PA_UNLESS( !pthread_attr_setscope( &attr, PTHREAD_SCOPE_SYSTEM ), paInternalError );   

    PA_UNLESS( !pthread_create( &self->thread, &attr, threadFunc, threadArg ), paInternalError );
    started = 1;

    if( rtSched )
    {
#if 0
        if( self->useWatchdog )
        {
            int err;
            struct sched_param wdSpm = { 0 };
            /* Launch watchdog, watchdog sets callback thread priority */
            int prio = PA_MIN( self->rtPrio + 4, sched_get_priority_max( SCHED_FIFO ) );
            wdSpm.sched_priority = prio;

            PA_UNLESS( !pthread_attr_init( &attr ), paInternalError );
            PA_UNLESS( !pthread_attr_setinheritsched( &attr, PTHREAD_EXPLICIT_SCHED ), paInternalError );
            PA_UNLESS( !pthread_attr_setscope( &attr, PTHREAD_SCOPE_SYSTEM ), paInternalError );
            PA_UNLESS( !pthread_attr_setschedpolicy( &attr, SCHED_FIFO ), paInternalError );
            PA_UNLESS( !pthread_attr_setschedparam( &attr, &wdSpm ), paInternalError );
            if( (err = pthread_create( &self->watchdogThread, &attr, &WatchdogFunc, self )) )
            {
                PA_UNLESS( err == EPERM, paInternalError );
                /* Permission error, go on without realtime privileges */
                PA_DEBUG(( "Failed bumping priority\n" ));
            }
            else
            {
                int policy;
                self->watchdogRunning = 1;
                PA_ENSURE_SYSTEM( pthread_getschedparam( self->watchdogThread, &policy, &wdSpm ), 0 );
                /* Check if priority is right, policy could potentially differ from SCHED_FIFO (but that's alright) */
                if( wdSpm.sched_priority != prio )
                {
                    PA_DEBUG(( "Watchdog priority not set correctly (%d)\n", wdSpm.sched_priority ));
                    PA_ENSURE( paInternalError );
                }
            }
        }
        else
#endif
            PA_ENSURE( BoostPriority( self ) );

        {
            int policy;
            struct sched_param spm;
            pthread_getschedparam(self->thread, &policy, &spm);
        }
    }
    
    if( self->parentWaiting )
    {
        PaTime till;
        struct timespec ts;
        int res = 0;
        PaTime now;

        PA_ENSURE( PaUnixMutex_Lock( &self->mtx ) );

        /* Wait for stream to be started */
        now = PaUtil_GetTime();
        till = now + waitForChild;

        while( self->parentWaiting && !res )