tlibbe.cxx

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/* 
 * tlibbe.cxx
 *
 * Thread library implementation for BeOS
 *
 * Portable Windows Library
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Portable Windows Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Portions are Copyright (c) 1993-1998 Equivalence Pty. Ltd.
 *
 * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
 * All Rights Reserved.
 *
 * Contributor(s): Yuri Kiryanov, ykiryanov at users.sourceforge.net
 *
 * $Revision: 19516 $
 * $Author: rjongbloed $
 * $Date: 2008-02-14 08:05:40 +0000 (Thu, 14 Feb 2008) $
 */

class PThread;
class PProcess;
class PSemaphore;
class PSyncPoint;

class PMutex; 

#include <ptlib.h>
#include <ptlib/socket.h>

#ifdef B_ZETA_VERSION 
#include <posix/rlimit.h>
#endif // Zeta

// For class BLocker
#include <be/support/Locker.h>

int PX_NewHandle(const char *, int);

#define DEBUG_SEMAPHORES1 1

//////////////////////////////////////////////////////////////////////////////
// Threads

static int const priorities[] = {
  1, // Lowest priority is 1. 0 is not
  B_LOW_PRIORITY,
  B_NORMAL_PRIORITY,
  B_DISPLAY_PRIORITY,
  B_URGENT_DISPLAY_PRIORITY,
};

int32 PThread::ThreadFunction(void * threadPtr)
{
  PThread * thread = (PThread *)PAssertNULL(threadPtr);

  PProcess & process = PProcess::Current();

  process.threadMutex.Wait();
  process.activeThreads.SetAt((unsigned) thread->mId, thread);
  process.threadMutex.Signal();

  process.OnThreadStart(*thread);

  thread->Main();

  process.OnThreadEnded(*thread);

  return 0;
}

PThread::PThread()
 : autoDelete(PTrue),
   mId(B_BAD_THREAD_ID),
   mPriority(B_NORMAL_PRIORITY),
   mStackSize(0),
   mSuspendCount(0)
{
}

void PThread::InitialiseProcessThread()
{
  autoDelete = PFalse;

  mId = find_thread(NULL);
  mPriority = B_NORMAL_PRIORITY;
  mStackSize = 0;
  mSuspendCount = 1;
  
  PAssert(::pipe(unblockPipe) == 0, "Pipe creation failed in InitialiseProcessThread!");
  PAssertOS(unblockPipe[0]);
  PAssertOS(unblockPipe[1]);
  
  ((PProcess *)this)->activeThreads.DisallowDeleteObjects();
  ((PProcess *)this)->activeThreads.SetAt(mId, this);
}

PThread::PThread(PINDEX stackSize,
                 AutoDeleteFlag deletion,
                 Priority priorityLevel,
                 const PString & name)
 : mId(B_BAD_THREAD_ID),
   mPriority(B_NORMAL_PRIORITY),
   mStackSize(0),
   mSuspendCount(0)
{
  PAssert(stackSize > 0, PInvalidParameter);
  autoDelete = deletion == AutoDeleteThread;
 
  mId =  ::spawn_thread(ThreadFunction, // Function 
         (const char*) name, // Name
         priorities[priorityLevel], // Priority 
         (void *) this); // Pass this as cookie

  PAssertOS(mId >= B_NO_ERROR);
    
  mSuspendCount = 1;
  mStackSize = stackSize;
  mPriority = priorities[priorityLevel];

  threadName.sprintf(name, mId);
  ::rename_thread(mId, (const char*) threadName); // real, unique name - with id

  PAssert(::pipe(unblockPipe) == 0, "Pipe creation failed in PThread constructor");
  PX_NewHandle("Thread unblock pipe", PMAX(unblockPipe[0], unblockPipe[1]));
}

PThread * PThread::Current()
{
  PProcess & process = PProcess::Current();
  process.threadMutex.Wait();
  PThread * thread = process.activeThreads.GetAt((unsigned)find_thread(NULL));
  process.threadMutex.Signal();
  return thread;    
}

PThread::~PThread()
{
  // if we are not process, remove this thread from the active thread list
  PProcess & process = PProcess::Current();
  if(process.GetThreadId() != GetThreadId())
  {
    process.threadMutex.Wait();
    process.activeThreads.RemoveAt((unsigned) mId);
    process.threadMutex.Signal();
  }

  if (!IsTerminated())
    Terminate();

  ::close(unblockPipe[0]);
  ::close(unblockPipe[1]);
}


void PThread::Restart()
{
  if(!IsTerminated())
    return;

  mId =  ::spawn_thread(ThreadFunction, // Function 
         "PWLT", // Name
          mPriority, 
          (void *) this); // Pass this as cookie

  PAssertOS(mId >= B_NO_ERROR);

  threadName.sprintf("PWLib Thread %d", mId);
  ::rename_thread(mId, (const char*) threadName); // real, unique name - with id
}

void PThread::Terminate()
{
  if(mStackSize <=0)
    return;

  if(mId == find_thread(NULL))
  {
    ::exit_thread(0);
    return;
  }

  if(IsTerminated())
    return;

  PXAbortBlock();
  WaitForTermination(20);

 if(mId > B_BAD_THREAD_ID)
   ::kill_thread(0);
}

PBoolean PThread::IsTerminated() const
{
  return mId == B_BAD_THREAD_ID;
}


void PThread::WaitForTermination() const
{
  WaitForTermination(PMaxTimeInterval);
}


PBoolean PThread::WaitForTermination(const PTimeInterval & /*maxWait*/) const // Fix timeout
{
  status_t result = B_NO_ERROR;
  status_t exit_value = B_NO_ERROR;

  result = ::wait_for_thread(mId, &exit_value);
  if ( result == B_INTERRUPTED ) { // thread was killed.
    return PTrue;
  }

  if ( result == B_OK ) { // thread is dead
    #ifdef DEBUG_THREADS
    PError << "B_OK" << endl;
    #endif
    return PTrue;
  }

  if ( result == B_BAD_THREAD_ID ) { // thread has invalid id
    return PTrue;
  }

  return PFalse;
}


void PThread::Suspend(PBoolean susp)
{

  PAssert(!IsTerminated(), "Operation on terminated thread");
  if (susp)
  {
    status_t result = ::suspend_thread(mId);
    if(B_OK == result)
	::atomic_add(&mSuspendCount, 1);

    PAssert(result == B_OK, "Thread don't want to be suspended");
  }
  else
    Resume();
}


void PThread::Resume()
{
  PAssert(!IsTerminated(), "Operation on terminated thread");
  status_t result = ::resume_thread(mId);
  if(B_OK == result)
    ::atomic_add(&mSuspendCount, -1);

  PAssert(result == B_NO_ERROR, "Thread doesn't want to resume");
}


PBoolean PThread::IsSuspended() const
{
  return (mSuspendCount > 0);
}

void PThread::SetAutoDelete(AutoDeleteFlag deletion)
{
  PAssert(deletion != AutoDeleteThread || this != &PProcess::Current(), PLogicError);
  autoDelete = deletion == AutoDeleteThread;
}

void PThread::SetPriority(Priority priorityLevel)
{
  PAssert(!IsTerminated(), "Operation on terminated thread");

  mPriority = priorities[priorityLevel];
  status_t result = ::set_thread_priority(mId, mPriority );
  if(result != B_OK)
    PTRACE(0, "Changing thread priority failed, error " << strerror(result) << endl);

}


PThread::Priority PThread::GetPriority() const
{
  if(!IsTerminated())
  {

  switch (mPriority) {
    case 0 :
      return LowestPriority;
    case B_LOW_PRIORITY :
      return LowPriority;
    case B_NORMAL_PRIORITY :
      return NormalPriority;
    case B_DISPLAY_PRIORITY :
      return HighPriority;
    case B_URGENT_DISPLAY_PRIORITY :
      return HighestPriority;
  }
  PAssertAlways(POperatingSystemError);
  
  }
  return LowestPriority;
}

void PThread::Yield()
{
  // we just sleep for long enough to cause a reschedule (100 microsec)
  ::snooze(100);
}

void PThread::Sleep( const PTimeInterval & delay ) // Time interval to sleep for.
{
  bigtime_t microseconds = 
		delay == PMaxTimeInterval ? B_INFINITE_TIMEOUT : (delay.GetMilliSeconds() * 1000 );
 
  status_t result = ::snooze( microseconds ) ; // delay in ms, snooze in microsec
  PAssert(result == B_OK, "Thread has insomnia");
}

int PThread::PXBlockOnChildTerminate(int pid, const PTimeInterval & /*timeout*/) // Fix timeout
{
  status_t result = B_NO_ERROR;
  status_t exit_value = B_NO_ERROR;

  result = ::wait_for_thread(pid, &exit_value);
  if ( result == B_INTERRUPTED ) 
  { 
    // thread was killed.
    #ifdef DEBUG_THREADS
    PError << "B_INTERRUPTED" << endl;
    #endif
    return 1;
  }

  if ( result == B_OK ) 
  { 
    // thread is dead
     return 1;
  }

  if ( result == B_BAD_THREAD_ID ) 
  { 
    // thread has invalid id
    return 1;
  }

  return 0; // ???
}

PThreadIdentifier PThread::GetCurrentThreadId(void)
{
  return ::find_thread(NULL);
}

int PThread::PXBlockOnIO(int handle, int type, const PTimeInterval & timeout)
{
  PTRACE(7, "PWLib\tPThread::PXBlockOnIO(" << handle << ',' << type << ')');

  if ((handle < 0) || (handle >= PProcess::Current().GetMaxHandles())) {
    PTRACE(2, "PWLib\tAttempt to use illegal handle in PThread::PXBlockOnIO, handle=" << handle);
    errno = EBADF;
    return -1;
  }