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#ifndef WIBBLE_SYS_THREAD_H
#define WIBBLE_SYS_THREAD_H
/*
* OO encapsulation of Posix threads
*
* Copyright (C) 2003--2008 Enrico Zini <enrico@debian.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <wibble/exception.h>
#include <pthread.h>
#include <signal.h>
namespace wibble {
namespace sys {
/**
* Encapsulates a thread
*
* FIXME: C++ resource management and thread cancellation
* C++ uses the "resource allocation is instantiation" way of managing
* resources: when a function exits, either by terminating or because
* an exception has been raised, destructors are called.
*
* However, when a thread is canceled, the flow of control is
* interrupted and no exceptions are thrown. Cleanup should be
* performed by registering cleanup functions, but a cleanup function
* can't usefully throw exceptions nor call destructors.
* At the moment, I don't know what to do to correctly release
* resources on thread cancellation. I'm waiting for new ideas.
*
* The current way out is not to use cancelation, but explicitly set
* some boolean exit condition:
*
* \code
* class MyThread
* {
* bool interrupted;
* void* main()
* {
* // do things
* if (interrupted)
* throw MyInterruptedException();
* // do things
* while (!interrupted)
* {
* // do things
* }
* }
* MyThread() : interrupted(false) {}
* }
* \endcode
*/
class Thread
{
protected:
pthread_t thread;
/**
* Short tag describing this thread, used in error messages and
* identification
*/
virtual const char* threadTag() { return "generic"; }
/** Main thread function, executed in the new thread after creation.
* When main() exits, the new thread ends and main() result will be the
* thread exit result
*/
virtual void* main() = 0;
/// Callback function used to start the thread
static void* Starter(void* parm);
void testcancel();
public:
virtual ~Thread() {}
/// Start the thread
void start();
/// Start the thread in the detached state
void startDetached();
/// Join the thread
void* join();
/// Put the thread in the detached state
void detach();
/// Send a cancellation request to the thread
void cancel();
/// Sent a signal to the thread
void kill(int signal);
};
}
}
// vim:set ts=4 sw=4:
#endif
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