//  $Id: PThread.cxx,v 1.12 1999/09/16 16:41:34 yoonforh Exp $
/////////////////////////////////////////////////////////////////////////////
/*
 * Copyright (c) 1998-2002 Yoon Kyung Koo(yoonforh@yahoo.com).
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL YOON KYUNG KOO OR THE OTHER
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
/////////////////////////////////////////////////////////////////////////////
//
//  DESCRIPTION
//  	a Thread class implementation
//
//	NOTE
//		This posix thread class implementation is based upon
//		 POSIX.1c standards(draft 10).
//		Using this class in prior draft environments
//		 without serious revision could lead to malfunction.
//		This implementation lacks of thread attribute support.
//		Several enhancements are added in UI thread version.
//		Should apply those enhancements in this pthread class impl.
//	TODO
//		-. DG/UX (draft 6) sets error number in errno variable
//		   but standard PTHREAD DOES NOT SET errno BUT pass
//		   as a RETURN VALUE!!!
//		   so, this Thread class DOES NOT SUPPORT DG/UX
//
///

/////////////////////////////////////////////////////////////////////////////
//                                                                         //
//  AUTHOR : Yoon Kyung Koo (yoonforh@yahoo.com)                           //
//                                                                         //
/////////////////////////////////////////////////////////////////////////////

#include <iostream>
#include "Thread.hxx"

/**
 * Semaphore class
 *	semaphore wrapper class
 *	implementation
 */
#define THREAD_SCOPE 0
Semaphore::Semaphore(int value)
{
    if (::sem_init(&sem, THREAD_SCOPE, value)<0)
	cerr << "sem_init:cannot initialize semaphore. " << ::strerror(errno) << endl;
}

Semaphore::~Semaphore()
{
    if (::sem_destroy(&sem)<0)
	cerr << "sem_destroy:cannot destroy semaphore. " << ::strerror(errno) << endl;
}

/**
 * Mutex class
 *	mutex wrapper class
 *	implementation
 */
Mutex::Mutex()
{
    int val;
    if ((val=::pthread_mutex_init(&mutex, NULL))!=0)
	cerr << "pthread_mutex_init:cannot initialize mutex. "
	     << ::strerror(val) << endl;
}

Mutex::~Mutex()
{
    int val;
    if ((val=::pthread_mutex_destroy(&mutex))!=0)
	cerr << "pthread_mutex_destroy:cannot destroy mutex. "
	     << ::strerror(val) << endl;
}

/**
 * CondVar class
 *	condition variable wrapper class
 *	implementation
 */
CondVar::CondVar(Mutex& mutex) : mutex(mutex)
{
    int val;
    if ((val=::pthread_cond_init(&cv, NULL))!=0)
	cerr << "pthread_cond_init:cannot initialize cv. "
	     << ::strerror(val) << endl;
}

CondVar::~CondVar()
{
    int val;
    if ((val=::pthread_cond_destroy(&cv))!=0)
	cerr << "pthread_cond_destroy:Cannot destroy cv. "
	     << ::strerror(val) << endl;
}

/**
 * Thread class
 *	thread wrapper class
 *	implementation
 * TO DO
 *  -. support for TSD(thread specific data)
 *  -. support for ThreadAttr
 *     (currently only stack size supported)
 */

Thread::Thread(const string& name, int stackSize=0)
    : name(name),status(THREAD_STATUS_NORMAL),running(false)
{
    int val;
    if ((val=::pthread_attr_init(&attr))!=0) {
	cerr << "pthread_attr_init:cannot initialize thread attribute. "
	     << ::strerror(val) << endl;
	status = THREAD_STATUS_FATAL;
	return;
    }
    if (stackSize > 0)
	if ((val=::pthread_attr_setstacksize(&attr, stackSize))!=0) {
	    cerr << "pthread_attr_setstacksize failed. "
		 << ::strerror(val) << endl;
	    status = THREAD_STATUS_FATAL;
	    return;
	}
    init();
}

// destructor
Thread::~Thread()
{
    cancel();
    cleanup();
}

// do nothing...
void
Thread::run()
{
#ifdef DEBUG
    cerr << "virtual Thread::run() called..." << endl;
#endif
}

// member functions

/**
 * init() : write codes what you want to do
 *			before thread start
 */
void
Thread::init()
{
#ifdef DEBUG
    cerr << "[virtual] init" << endl;
#endif
}

/**
 * cleanup() : write codes what you want to do
 *			after thread quit
 */
void
Thread::cleanup()
{
#ifdef DEBUG
    cerr << "[virtual] cleanup" << endl;
#endif
    // by default detach thread
    // this function assumes that this thread was running in non-detached mode
    detach();
}


/**
 * Thread::_run() :
 *  private/static method invoking this thread object's run() method
 */
void *
Thread::_run(void * arg) {
    // NOTE: do not use global scope symbol '::' in front of macros
    // pthread_cleanup_push or pthread_cleanup_pop
    // they does some freakish hacks
    pthread_cleanup_push(_cleanup, arg); // should be provided in pair with cleanup_pop
    ((Thread *)arg)->run();
    ((Thread *)arg)->setFatalStatus(); // after run, thread exits
    pthread_cleanup_pop(1); // should be provided in pair with cleanup_push
    return NULL;
}