public bool ReleaseLock()
{
//Need to own the lock in order to release it (and we can reacquire the lock inside the current process)
if (LockIO.LockExists(LockFilePath) && TryAcquireLock())
{
LockIO.DeleteLock(LockFilePath);
}
return(true);
}
public static SimpleFileLock Create(string lockName, [Optional] TimeSpan lockTimeout)
{
if (string.IsNullOrEmpty(lockName))
{
throw new ArgumentNullException("lockName", "lockName cannot be null or emtpy.");
}
return(new SimpleFileLock(lockName, lockTimeout)
{
LockFilePath = LockIO.GetFilePath(lockName)
});
}
public void TryAcquireLock_LockedByActiveProcess_ReturnsFalse()
{
LockIO.WriteLock(LockPath, new FileLockContent
{
PID = ActiveProcessId,
ProcessName = GetSafeActiveProcessName(),
Timestamp = DateTime.Now.Ticks
});
SimpleFileLock fileLock = SimpleFileLock.Create("SimpleFileLockTests");
Assert.That(fileLock.TryAcquireLock(), Is.False);
}
public void TryAcquireLock_LockedByActiveProcessTimedOut_ReturnsTrue()
{
LockIO.WriteLock(LockPath, new FileLockContent
{
PID = ActiveProcessId,
ProcessName = GetSafeActiveProcessName(),
Timestamp = (DateTime.Now - TimeSpan.FromHours(2)).Ticks
});
SimpleFileLock fileLock = SimpleFileLock.Create("SimpleFileLockTests", TimeSpan.FromHours(1));
Assert.That(fileLock.TryAcquireLock(), Is.True);
}
public void TryAcquireLock_LockedByDeadProcess_ReturnsTrue()
{
LockIO.WriteLock(LockPath, new FileLockContent
{
PID = 9999,
ProcessName = Path.GetRandomFileName(),
Timestamp = DateTime.Now.Ticks
});
SimpleFileLock fileLock = SimpleFileLock.Create("SimpleFileLockTests");
Assert.That(fileLock.TryAcquireLock(), Is.True);
fileLock.ReleaseLock();
}
public void ReleaseLock_LockedByActiveProcess_LockFileExists()
{
LockIO.WriteLock(LockPath, new FileLockContent
{
PID = ActiveProcessId,
ProcessName = GetSafeActiveProcessName(),
Timestamp = DateTime.Now.Ticks
});
SimpleFileLock fileLock = SimpleFileLock.Create("SimpleFileLockTests");
fileLock.ReleaseLock();
Assert.That(File.Exists(LockPath), Is.True);
}
public bool TryAcquireLock()
{
if (LockIO.LockExists(LockFilePath))
{
var lockContent = LockIO.ReadLock(LockFilePath);
//Someone else owns the lock
if (lockContent.GetType() == typeof(OtherProcessOwnsFileLockContent))
{
return(false);
}
//the file no longer exists
if (lockContent.GetType() == typeof(MissingFileLockContent))
{
return(AcquireLock());
}
//This lock belongs to this process - we can reacquire the lock
if (lockContent.PID == Process.GetCurrentProcess().Id)
{
return(AcquireLock());
}
//The process which created it is no longer running
if (!ProcessIsRunning((int)lockContent.PID, lockContent.ProcessName))
{
return(AcquireLock());
}
if (LockTimeout != TimeSpan.Zero)
{
var lockWriteTime = new DateTime(lockContent.Timestamp);
if (!(Math.Abs((DateTime.Now - lockWriteTime).TotalSeconds) > LockTimeout.TotalSeconds))
{
return(false); //The lock has not timed out - we can't acquire it
}
}
else
{
return(false);
}
}
//Acquire the lock
return(AcquireLock());
}
public bool TryAcquireLock()
{
if (LockIO.LockExists(LockFilePath))
{
var lockContent = LockIO.ReadLock(LockFilePath);
//Someone else owns the lock
if (lockContent.GetType() == typeof(OtherProcessOwnsFileLockContent))
{
return(false);
}
//the file no longer exists
if (lockContent.GetType() == typeof(MissingFileLockContent))
{
return(AcquireLock());
}
var lockWriteTime = new DateTime(lockContent.Timestamp);
//This lock belongs to this process - we can reacquire the lock
var currentProcess = Process.GetCurrentProcess();
if (lockContent.PID == currentProcess.Id && lockContent.MachineName == Environment.MachineName)
{
return(AcquireLock());
}
//The lock has not timed out - we can't acquire it
if (!(Math.Abs((DateTime.Now - lockWriteTime).TotalSeconds) > LockTimeout.TotalSeconds))
{
return(false);
}
}
//Acquire the lock
return(AcquireLock());
}
private bool AcquireLock()
{
return(LockIO.WriteLock(LockFilePath, CreateLockContent()));
}