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aelocker.h
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82 lines (70 loc) · 1.8 KB
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#pragma once
class AeLocker
{
bool m_fArmed = false;
public:
AeLocker()
{
}
void arm(client *c = nullptr, bool fIfNeeded = false) // if a client is passed, then the client is already locked
{
if (m_fArmed)
return;
if (fIfNeeded && aeThreadOwnsLock())
return;
serverAssertDebug(!GlobalLocksAcquired());
if (c != nullptr)
{
serverAssert(!m_fArmed);
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();
}
};