zoneminder/src/zm_thread.cpp

302 lines
9.1 KiB
C++

//
// ZoneMinder Thread Class Implementation, $Date$, $Revision$
// Copyright (C) 2001-2008 Philip Coombes
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
#include "zm_thread.h"
#include "zm_logger.h"
#include "zm_utils.h"
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <sys/time.h>
struct timespec getTimeout( int secs ) {
struct timespec timeout;
struct timeval temp_timeout;
gettimeofday(&temp_timeout, 0);
timeout.tv_sec = temp_timeout.tv_sec + secs;
timeout.tv_nsec = temp_timeout.tv_usec*1000;
return timeout;
}
struct timespec getTimeout( double secs ) {
struct timespec timeout;
struct timeval temp_timeout;
gettimeofday( &temp_timeout, 0 );
timeout.tv_sec = temp_timeout.tv_sec + int(secs);
timeout.tv_nsec = temp_timeout.tv_usec += (long int)(1000000000.0*(secs-int(secs)));
if ( timeout.tv_nsec > 1000000000 ) {
timeout.tv_sec += 1;
timeout.tv_nsec -= 1000000000;
}
return timeout;
}
Mutex::Mutex() {
if ( pthread_mutex_init(&mMutex, NULL) < 0 )
Error("Unable to create pthread mutex: %s", strerror(errno));
}
Mutex::~Mutex() {
if ( locked() )
Warning("Destroying mutex when locked");
if ( pthread_mutex_destroy(&mMutex) < 0 )
Error("Unable to destroy pthread mutex: %s", strerror(errno));
}
int Mutex::trylock() {
return pthread_mutex_trylock(&mMutex);
}
void Mutex::lock() {
if ( pthread_mutex_lock(&mMutex) < 0 )
throw ThreadException( stringtf( "Unable to lock pthread mutex: %s", strerror(errno) ) );
}
void Mutex::lock( int secs ) {
struct timespec timeout = getTimeout( secs );
if ( pthread_mutex_timedlock( &mMutex, &timeout ) < 0 )
throw ThreadException( stringtf( "Unable to timedlock pthread mutex: %s", strerror(errno) ) );
}
void Mutex::lock( double secs ) {
struct timespec timeout = getTimeout( secs );
if ( pthread_mutex_timedlock( &mMutex, &timeout ) < 0 )
throw ThreadException( stringtf( "Unable to timedlock pthread mutex: %s", strerror(errno) ) );
}
void Mutex::unlock() {
if ( pthread_mutex_unlock( &mMutex ) < 0 )
throw ThreadException( stringtf( "Unable to unlock pthread mutex: %s", strerror(errno) ) );
}
bool Mutex::locked() {
int state = pthread_mutex_trylock( &mMutex );
if ( state != 0 && state != EBUSY )
throw ThreadException( stringtf( "Unable to trylock pthread mutex: %s", strerror(errno) ) );
if ( state != EBUSY )
unlock();
return( state == EBUSY );
}
Condition::Condition( Mutex &mutex ) : mMutex( mutex ) {
if ( pthread_cond_init( &mCondition, NULL ) < 0 )
throw ThreadException( stringtf( "Unable to create pthread condition: %s", strerror(errno) ) );
}
Condition::~Condition() {
if ( pthread_cond_destroy( &mCondition ) < 0 )
Error("Unable to destroy pthread condition: %s", strerror(errno));
}
void Condition::wait() {
// Locking done outside of this function
if ( pthread_cond_wait( &mCondition, mMutex.getMutex() ) < 0 )
throw ThreadException( stringtf( "Unable to wait pthread condition: %s", strerror(errno) ) );
}
bool Condition::wait( int secs ) {
// Locking done outside of this function
Debug( 8, "Waiting for %d seconds", secs );
struct timespec timeout = getTimeout( secs );
if ( pthread_cond_timedwait( &mCondition, mMutex.getMutex(), &timeout ) < 0 && errno != ETIMEDOUT )
throw ThreadException( stringtf( "Unable to timedwait pthread condition: %s", strerror(errno) ) );
return( errno != ETIMEDOUT );
}
bool Condition::wait( double secs ) {
// Locking done outside of this function
struct timespec timeout = getTimeout( secs );
if ( pthread_cond_timedwait( &mCondition, mMutex.getMutex(), &timeout ) < 0 && errno != ETIMEDOUT )
throw ThreadException( stringtf( "Unable to timedwait pthread condition: %s", strerror(errno) ) );
return( errno != ETIMEDOUT );
}
void Condition::signal() {
if ( pthread_cond_signal( &mCondition ) < 0 )
throw ThreadException( stringtf( "Unable to signal pthread condition: %s", strerror(errno) ) );
}
void Condition::broadcast() {
if ( pthread_cond_broadcast( &mCondition ) < 0 )
throw ThreadException( stringtf( "Unable to broadcast pthread condition: %s", strerror(errno) ) );
}
template <class T> const T ThreadData<T>::getValue() const {
mMutex.lock();
const T valueCopy = mValue;
mMutex.unlock();
return( valueCopy );
}
template <class T> T ThreadData<T>::setValue( const T value ) {
mMutex.lock();
const T valueCopy = mValue = value;
mMutex.unlock();
return( valueCopy );
}
template <class T> const T ThreadData<T>::getUpdatedValue() const {
Debug( 8, "Waiting for value update, %p", this );
mMutex.lock();
mChanged = false;
//do {
mCondition.wait();
//} while ( !mChanged );
const T valueCopy = mValue;
mMutex.unlock();
Debug( 9, "Got value update, %p", this );
return( valueCopy );
}
template <class T> const T ThreadData<T>::getUpdatedValue( double secs ) const {
Debug( 8, "Waiting for value update, %.2f secs, %p", secs, this );
mMutex.lock();
mChanged = false;
//do {
mCondition.wait( secs );
//} while ( !mChanged );
const T valueCopy = mValue;
mMutex.unlock();
Debug( 9, "Got value update, %p", this );
return( valueCopy );
}
template <class T> const T ThreadData<T>::getUpdatedValue( int secs ) const {
Debug( 8, "Waiting for value update, %d secs, %p", secs, this );
mMutex.lock();
mChanged = false;
//do {
mCondition.wait( secs );
//} while ( !mChanged );
const T valueCopy = mValue;
mMutex.unlock();
Debug( 9, "Got value update, %p", this );
return( valueCopy );
}
template <class T> void ThreadData<T>::updateValueSignal( const T value ) {
Debug( 8, "Updating value with signal, %p", this );
mMutex.lock();
mValue = value;
mChanged = true;
mCondition.signal();
mMutex.unlock();
Debug( 9, "Updated value, %p", this );
}
template <class T> void ThreadData<T>::updateValueBroadcast( const T value ) {
Debug( 8, "Updating value with broadcast, %p", this );
mMutex.lock();
mValue = value;
mChanged = true;
mCondition.broadcast();
mMutex.unlock();
Debug( 9, "Updated value, %p", this );
}
Thread::Thread() :
mThreadCondition( mThreadMutex ),
mPid( -1 ),
mStarted( false ),
mRunning( false )
{
Debug( 1, "Creating thread" );
}
Thread::~Thread() {
Debug( 1, "Destroying thread %d", mPid );
if ( mStarted )
join();
}
void *Thread::mThreadFunc( void *arg ) {
Debug( 2, "Invoking thread" );
Thread *thisPtr = (Thread *)arg;
thisPtr->status = 0;
try {
thisPtr->mThreadMutex.lock();
thisPtr->mPid = thisPtr->id();
thisPtr->mThreadCondition.signal();
thisPtr->mThreadMutex.unlock();
thisPtr->mRunning = true;
thisPtr->status = thisPtr->run();
thisPtr->mRunning = false;
Debug( 2, "Exiting thread, status %p", (void *)&(thisPtr->status) );
return (void *)&(thisPtr->status);
} catch ( const ThreadException &e ) {
Error( "%s", e.getMessage().c_str() );
thisPtr->mRunning = false;
Debug( 2, "Exiting thread after exception, status %p", (void *)-1 );
return (void *)-1;
}
}
void Thread::start() {
Debug( 1, "Starting thread" );
if ( isThread() )
throw ThreadException( "Can't self start thread" );
mThreadMutex.lock();
if ( !mStarted ) {
pthread_attr_t threadAttrs;
pthread_attr_init( &threadAttrs );
pthread_attr_setscope( &threadAttrs, PTHREAD_SCOPE_SYSTEM );
mStarted = true;
if ( pthread_create( &mThread, &threadAttrs, mThreadFunc, this ) < 0 )
throw ThreadException( stringtf( "Can't create thread: %s", strerror(errno) ) );
pthread_attr_destroy( &threadAttrs );
} else {
Error( "Attempt to start already running thread %d", mPid );
}
mThreadCondition.wait();
mThreadMutex.unlock();
Debug( 1, "Started thread %d", mPid );
}
void Thread::join() {
Debug( 1, "Joining thread %d", mPid );
if ( isThread() )
throw ThreadException( "Can't self join thread" );
mThreadMutex.lock();
if ( mPid >= 0 ) {
if ( mStarted ) {
void *threadStatus = 0;
if ( pthread_join( mThread, &threadStatus ) < 0 )
throw ThreadException( stringtf( "Can't join sender thread: %s", strerror(errno) ) );
mStarted = false;
Debug( 1, "Thread %d exited, status %p", mPid, threadStatus );
} else {
Warning( "Attempt to join already finished thread %d", mPid );
}
} else {
Warning( "Attempt to join non-started thread %d", mPid );
}
mThreadMutex.unlock();
Debug( 1, "Joined thread %d", mPid );
}
void Thread::kill( int signal ) {
pthread_kill( mThread, signal );
}
// Some explicit template instantiations
#include "zm_threaddata.cpp"