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/*==LICENSE==*
CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011 Cyan Worlds, Inc.
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 3 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, see <http://www.gnu.org/licenses/>.
You can contact Cyan Worlds, Inc. by email legal@cyan.com
or by snail mail at:
Cyan Worlds, Inc.
14617 N Newport Hwy
Mead, WA 99021
*==LICENSE==*/
/*****************************************************************************
*
* $/Plasma20/Sources/Plasma/NucleusLib/pnUtils/Private/Win32/pnUtW32Sync.cpp
*
***/
#include "../../Pch.h"
#pragma hdrstop
/****************************************************************************
*
* Spin lock functions
*
***/
//===========================================================================
static inline void EnterSpinLock (long * spinLock) {
for (;;)
if (*spinLock < 0)
if (!InterlockedIncrement(spinLock))
return;
else
InterlockedDecrement(spinLock);
}
//===========================================================================
static inline void LeaveSpinLock (long * spinLock) {
InterlockedDecrement(spinLock);
}
/****************************************************************************
*
* CLockWaitSet / CLockWaitSetAllocator
*
***/
class CLockWaitSet {
private:
unsigned m_refCount;
HANDLE m_waitEvent;
public:
LINK(CLockWaitSet) link;
inline CLockWaitSet ();
inline ~CLockWaitSet ();
inline void DecRef ();
inline void IncRef ();
inline void Signal ();
inline void Wait ();
};
class CLockWaitSetAllocator {
private:
CLockWaitSet m_array[256];
CLockWaitSetAllocator * m_prev;
LISTDECL(CLockWaitSet, link) m_spareList;
LISTDECL(CLockWaitSet, link) m_usedList;
static CLockWaitSetAllocator * s_allocator;
static long s_spinLock;
public:
CLockWaitSetAllocator (CLockWaitSetAllocator * prev);
~CLockWaitSetAllocator ();
static CLockWaitSet * Alloc ();
static void Free (CLockWaitSet * waitSet);
static void __cdecl Shutdown ();
};
CLockWaitSetAllocator * CLockWaitSetAllocator::s_allocator;
long CLockWaitSetAllocator::s_spinLock = -1;
//===========================================================================
CLockWaitSet::CLockWaitSet () {
m_refCount = 0;
m_waitEvent = CreateEvent(nil, true, false, nil);
}
//===========================================================================
CLockWaitSet::~CLockWaitSet () {
ASSERT(!m_refCount);
CloseHandle(m_waitEvent);
m_waitEvent = 0;
}
//===========================================================================
void CLockWaitSet::DecRef () {
ASSERT(m_refCount);
if (!--m_refCount) {
ResetEvent(m_waitEvent);
CLockWaitSetAllocator::Free(this);
}
}
//===========================================================================
void CLockWaitSet::IncRef () {
++m_refCount;
}
//===========================================================================
void CLockWaitSet::Signal () {
ASSERT(m_refCount);
SetEvent(m_waitEvent);
}
//===========================================================================
void CLockWaitSet::Wait () {
ASSERT(m_refCount);
WaitForSingleObject(m_waitEvent, INFINITE);
}
//===========================================================================
CLockWaitSetAllocator::CLockWaitSetAllocator (CLockWaitSetAllocator * prev) {
m_prev = prev;
if (prev) {
m_spareList.Link(&prev->m_spareList);
m_usedList.Link(&prev->m_usedList);
}
for (unsigned index = arrsize(m_array); index--; )
m_spareList.Link(&m_array[index]);
}
//===========================================================================
CLockWaitSetAllocator::~CLockWaitSetAllocator () {
DEL(m_prev);
}
//===========================================================================
CLockWaitSet * CLockWaitSetAllocator::Alloc () {
EnterSpinLock(&s_spinLock);
// If there is no active allocator or if the active allocator is full,
// create a new one
if (!s_allocator || !s_allocator->m_spareList.Head()) {
if (!s_allocator)
atexit(Shutdown);
s_allocator = NEW(CLockWaitSetAllocator)(s_allocator);
}
// Get an available wait set from the active allocator
CLockWaitSet * waitSet = s_allocator->m_spareList.Head();
s_allocator->m_usedList.Link(waitSet);
LeaveSpinLock(&s_spinLock);
return waitSet;
}
//===========================================================================
void CLockWaitSetAllocator::Free (CLockWaitSet * waitSet) {
EnterSpinLock(&s_spinLock);
// Return this wait set to the active allocator's spare list
ASSERT(s_allocator);
s_allocator->m_spareList.Link(waitSet);
LeaveSpinLock(&s_spinLock);
}
//===========================================================================
void CLockWaitSetAllocator::Shutdown () {
EnterSpinLock(&s_spinLock);
// Free all allocators
while (s_allocator) {
CLockWaitSetAllocator * prev = s_allocator->m_prev;
DEL(s_allocator);
s_allocator = prev;
}
LeaveSpinLock(&s_spinLock);
}
/****************************************************************************
*
* CLock
*
***/
//===========================================================================
CLock::CLock () {
m_waitSet = nil;
m_spinLock = -1;
m_readerCount = 0;
m_writerCount = 0;
}
//===========================================================================
CLock::~CLock () {
ASSERT(!m_waitSet);
ASSERT(m_spinLock == -1);
ASSERT(!m_readerCount);
ASSERT(!m_writerCount);
}
//===========================================================================
void CLock::EnterRead () {
EnterSpinLock(&m_spinLock);
for (;;) {
// If there are no writers, claim this lock for reading
if (!m_writerCount) {
++m_readerCount;
break;
}
// Otherwise, wait until the existing writer releases the lock
CLockWaitSet * waitSet = m_waitSet = (m_waitSet ? m_waitSet : CLockWaitSetAllocator::Alloc());
waitSet->IncRef();
LeaveSpinLock(&m_spinLock);
waitSet->Wait();
EnterSpinLock(&m_spinLock);
waitSet->DecRef();
}
LeaveSpinLock(&m_spinLock);
}
//===========================================================================
void CLock::EnterWrite () {
EnterSpinLock(&m_spinLock);
for (;;) {
// If there are no readers or writers, claim this lock for writing
if (!m_readerCount && !m_writerCount) {
++m_writerCount;
break;
}
// Otherwise, wait until the existing writer or all existing readers
// release the lock
CLockWaitSet * waitSet = m_waitSet = (m_waitSet ? m_waitSet : CLockWaitSetAllocator::Alloc());
waitSet->IncRef();
LeaveSpinLock(&m_spinLock);
waitSet->Wait();
EnterSpinLock(&m_spinLock);
waitSet->DecRef();
}
LeaveSpinLock(&m_spinLock);
}
//===========================================================================
void CLock::LeaveRead () {
EnterSpinLock(&m_spinLock);
// If this is the last reader, signal waiting threads to try claiming
// the lock again
ASSERT(m_readerCount);
if (!--m_readerCount)
if (m_waitSet) {
m_waitSet->Signal();
m_waitSet = nil;
}
LeaveSpinLock(&m_spinLock);
}
//===========================================================================
void CLock::LeaveWrite () {
EnterSpinLock(&m_spinLock);
// This is the last writer. Signal waiting threads to try claiming the
// lock again.
ASSERT(m_writerCount == 1);
--m_writerCount;
if (m_waitSet) {
m_waitSet->Signal();
m_waitSet = nil;
}
LeaveSpinLock(&m_spinLock);
}
/*****************************************************************************
*
* CEvent
*
***/
//============================================================================
CEvent::CEvent (
ECEventResetBehavior resetType,
bool initialSet
) {
m_handle = CreateEvent(
nil, // security attributes
(resetType == kEventManualReset) ? true : false,
initialSet,
nil // name
);
}
//============================================================================
CEvent::~CEvent () {
(void) CloseHandle(m_handle);
}
//============================================================================
void CEvent::Signal () {
SetEvent(m_handle);
}
//============================================================================
void CEvent::Reset () {
ResetEvent(m_handle);
}
//============================================================================
bool CEvent::Wait (unsigned waitMs) {
ThreadAssertCanBlock(__FILE__, __LINE__);
return WaitForSingleObject(m_handle, waitMs) == WAIT_OBJECT_0;
}
/****************************************************************************
*
* Exported functions
*
***/
//===========================================================================
long AtomicAdd (long * value, long increment) {
return InterlockedExchangeAdd(value, increment);
}
//===========================================================================
long AtomicSet (long * value, long set) {
return InterlockedExchange(value, set);
}