AuroraRuntime/Source/IO/Loop/LSMutex.Linux.cpp

109 lines
2.3 KiB
C++

/***
Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.
File: LSMutex.Linux.cpp
Date: 2021-10-1
Date: 2022-4-4
Author: Reece
***/
#include <Source/RuntimeInternal.hpp>
#include "LSMutex.hpp"
#include "LSFromFdNonblocking.hpp"
namespace Aurora::IO::Loop
{
LSMutex::LSMutex()
{
Init();
}
LSMutex::LSMutex(int handle)
{
this->handle = handle;
}
LSMutex::~LSMutex()
{
if ((!this->bOwns) &&
(!this->bNoAutoRel /*must the remote grug clean up the IPC mutex? lets not hit a double unlock assert...*/))
{
SysPushErrorIO("Mutex owned by calling process during destruction... Forcefully unlocking...");
Unlock();
}
if ((this->handle != 0) &&
(this->handle != -1))
{
::close(AuExchange(this->handle, -1));
}
}
bool LSMutex::OnTrigger(AuUInt handle)
{
return IsSignaledNonblocking();
}
void LSMutex::Init()
{
handle = ::eventfd(1, EFD_NONBLOCK | EFD_CLOEXEC );
}
bool LSMutex::Unlock()
{
AuUInt64 plsNoOverflow {1};
bool ok = ::write(this->handle, &plsNoOverflow, sizeof(plsNoOverflow)) == 8;
if (ok)
{
this->bOwns = false;
}
return ok;
}
bool LSMutex::IsSignaled()
{
return IsSignaledFromNonblockingImpl(this, this, &LSMutex::IsSignaledNonblocking);
}
bool LSMutex::WaitOn(AuUInt32 timeout)
{
return LSHandle::WaitOn(timeout);
}
bool LSMutex::IsSignaledNonblocking()
{
AuUInt64 oldSemaphoreValue {};
auto read = ::read(this->handle, &oldSemaphoreValue, sizeof(oldSemaphoreValue));
auto ok = read == 8;
SysAssertDbg(!ok || oldSemaphoreValue == 1, "Double unlock caught");
if (!ok)
{
// TODO: Might hook here
}
else
{
this->bOwns = true;
}
return ok;
}
ELoopSource LSMutex::GetType()
{
return ELoopSource::eSourceMutex;
}
AUKN_SYM AuSPtr<ILSMutex> NewLSMutex()
{
auto pMutex = AuMakeShared<LSMutex>();
if (!pMutex)
{
return {};
}
if (!pMutex->HasValidHandle())
{
return {};
}
return pMutex;
}
}