futriix/src/aelocker.h
John Sully 4360d1ab3d Avoid locking as late as possible
Former-commit-id: acc894fe41d4e8869f28928cb0feffa1792c11c4
2020-01-11 19:28:13 -05:00

76 lines
1.6 KiB
C++

#pragma once
class AeLocker
{
bool m_fArmed = false;
public:
AeLocker()
{
}
void arm(client *c) // if a client is passed, then the client is already locked
{
if (m_fArmed)
return;
if (c != nullptr)
{
serverAssert(c->lock.fOwnLock());
if (!aeTryAcquireLock(true /*fWeak*/)) // avoid locking the client if we can
{
bool fOwnClientLock = true;
int clientNesting = 1;
for (;;)
{
if (fOwnClientLock)
{
clientNesting = c->lock.unlock_recursive();
fOwnClientLock = false;
}
aeAcquireLock();
if (!c->lock.try_lock(false)) // ensure a strong try because aeAcquireLock is expensive
{
aeReleaseLock();
}
else
{
break;
}
}
c->lock.lock_recursive(clientNesting);
}
m_fArmed = true;
}
else if (!m_fArmed)
{
m_fArmed = true;
aeAcquireLock();
}
}
void disarm()
{
serverAssert(m_fArmed);
m_fArmed = false;
aeReleaseLock();
}
bool isArmed() const
{
return m_fArmed;
}
void release()
{
m_fArmed = false;
}
~AeLocker()
{
if (m_fArmed)
aeReleaseLock();
}
};