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// This may look like C code, but it is really -*- C++ -*-
//
// Copyright Bob Friesenhahn, 1999, 2000, 2001, 2002
//
// Implementation of thread support
//
#define MAGICKCORE_IMPLEMENTATION 1
#define MAGICK_PLUSPLUS_IMPLEMENTATION 1
#include "Magick++/Thread.h"
#include "Magick++/Exception.h"
#include <string.h>
// Default constructor
Magick::MutexLock::MutexLock(void)
#if defined(MAGICKCORE_HAVE_PTHREAD)
// POSIX threads
: _mutex()
{
::pthread_mutexattr_t attr;
int sysError;
if ( (sysError = ::pthread_mutexattr_init( &attr )) == 0 )
if ( (sysError = ::pthread_mutex_init( &_mutex, &attr )) == 0 )
{
::pthread_mutexattr_destroy( &attr );
return;
}
throwExceptionExplicit( OptionError, "mutex initialization failed",
strerror(sysError) );
}
#else
#if defined(_VISUALC_) && defined(_MT)
// Win32 threads
: _mutex()
{
SECURITY_ATTRIBUTES security;
/* Allow the semaphore to be inherited */
security.nLength = sizeof(security);
security.lpSecurityDescriptor = NULL;
security.bInheritHandle = TRUE;
/* Create the semaphore, with initial value signaled */
_mutex.id = ::CreateSemaphore(&security, 1, MAXSEMLEN, NULL);
if ( _mutex.id != NULL )
return;
throwExceptionExplicit( OptionError, "mutex initialization failed" );
}
#else
// Threads not supported
{
}
#endif
#endif
// Destructor
Magick::MutexLock::~MutexLock(void)
{
#if defined(MAGICKCORE_HAVE_PTHREAD)
int sysError;
if ( (sysError = ::pthread_mutex_destroy( &_mutex )) == 0 )
return;
throwExceptionExplicit( OptionError, "mutex destruction failed",
strerror(sysError) );
#endif
#if defined(_MT) && defined(_VISUALC_)
if ( ::CloseHandle(_mutex.id) != 0 )
return;
throwExceptionExplicit( OptionError, "mutex destruction failed" );
#endif
}
// Lock mutex
void Magick::MutexLock::lock(void)
{
#if defined(MAGICKCORE_HAVE_PTHREAD)
int sysError;
if ( (sysError = ::pthread_mutex_lock( &_mutex )) == 0)
return;
throwExceptionExplicit( OptionError, "mutex lock failed",
strerror(sysError));
#endif
#if defined(_MT) && defined(_VISUALC_)
if (WaitForSingleObject(_mutex.id,INFINITE) != WAIT_FAILED)
return;
throwExceptionExplicit( OptionError, "mutex lock failed" );
#endif
}
// Unlock mutex
void Magick::MutexLock::unlock(void)
{
#if defined(MAGICKCORE_HAVE_PTHREAD)
int sysError;
if ( (sysError = ::pthread_mutex_unlock( &_mutex )) == 0)
return;
throwExceptionExplicit( OptionError, "mutex unlock failed",
strerror(sysError) );
#endif
#if defined(_MT) && defined(_VISUALC_)
if ( ReleaseSemaphore(_mutex.id, 1, NULL) == TRUE )
return;
throwExceptionExplicit( OptionError, "mutex unlock failed" );
#endif
}