59 lines
923 B
C++
59 lines
923 B
C++
#pragma once
|
|
#include "stdafx.h"
|
|
|
|
class SimpleLock
|
|
{
|
|
private:
|
|
DWORD _holderThreadID;
|
|
uint32_t _lockCount;
|
|
atomic_flag _lock;
|
|
|
|
public:
|
|
SimpleLock()
|
|
{
|
|
_lockCount = 0;
|
|
_holderThreadID = ~0;
|
|
}
|
|
|
|
void Acquire()
|
|
{
|
|
if(_lockCount == 0 || _holderThreadID != GetCurrentThreadId()) {
|
|
while(_lock.test_and_set());
|
|
_holderThreadID = GetCurrentThreadId();
|
|
_lockCount = 1;
|
|
} else {
|
|
//Same thread can acquire the same lock multiple times
|
|
_lockCount++;
|
|
}
|
|
}
|
|
|
|
bool IsFree()
|
|
{
|
|
if(!_lock.test_and_set()) {
|
|
_lock.clear();
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void WaitForRelease()
|
|
{
|
|
//Wait until we are able to grab a lock, and then release it again
|
|
Acquire();
|
|
Release();
|
|
}
|
|
|
|
void Release()
|
|
{
|
|
if(_lockCount > 0 && _holderThreadID == GetCurrentThreadId()) {
|
|
_lockCount--;
|
|
if(_lockCount == 0) {
|
|
_holderThreadID = ~0;
|
|
_lock.clear();
|
|
}
|
|
} else {
|
|
assert(false);
|
|
}
|
|
}
|
|
};
|
|
|