public void WriteLock_should_be_exclusive()
{
var lockId = Guid.NewGuid().ToString();
using (var readWriteLock1 = new TinyReadWriteLock(lockId, 2, TimeSpan.FromMilliseconds(0)))
using (var readWriteLock2 = new TinyReadWriteLock(lockId, 2, TimeSpan.FromMilliseconds(0)))
{
// Aquire the first lock
readWriteLock1.AcquireWriteLock();
// The second lock should now throw TimeoutException
Assert.Throws <TimeoutException>(() => readWriteLock2.AcquireWriteLock());
// Make sure the expected locks are held
Assert.True(readWriteLock1.IsWriterLockHeld);
Assert.False(readWriteLock2.IsWriterLockHeld);
// By releasing the first lock, the second lock should now be able to be held
readWriteLock1.ReleaseWriteLock();
readWriteLock2.AcquireWriteLock();
// Make sure the expected locks are held
Assert.False(readWriteLock1.IsWriterLockHeld);
Assert.True(readWriteLock2.IsWriterLockHeld);
}
}
public void Calling_ReleaseWriteLock_without_any_lock_held_should_throw()
{
using (var readWriteLock = new TinyReadWriteLock(Guid.NewGuid().ToString(), 1))
{
Assert.Throws <SemaphoreFullException>(() => readWriteLock.ReleaseWriteLock());
}
}
public void Calling_ReleaseWriteLock_should_release_locks()
{
using var readWriteLock = new TinyReadWriteLock(Guid.NewGuid().ToString(), 2);
readWriteLock.AcquireWriteLock();
Assert.True(readWriteLock.IsWriterLockHeld);
readWriteLock.ReleaseWriteLock();
Assert.False(readWriteLock.IsWriterLockHeld);
}
public void Calling_AcquireWriteLock_then_AquireReadLock_should_wait_for_other_lock()
{
var lockId = Guid.NewGuid().ToString();
using (var readWriteLock1 = new TinyReadWriteLock(lockId, 2))
using (var readWriteLock2 = new TinyReadWriteLock(lockId, 2))
{
readWriteLock1.AcquireWriteLock();
Task.Factory.StartNew(() => readWriteLock2.AcquireReadLock());
Thread.Sleep(50);
Assert.True(readWriteLock1.IsWriterLockHeld);
Assert.False(readWriteLock2.IsReaderLockHeld);
readWriteLock1.ReleaseWriteLock();
Thread.Sleep(50);
Assert.False(readWriteLock1.IsWriterLockHeld);
Assert.True(readWriteLock2.IsReaderLockHeld);
}
}
public void WriteLock_should_be_exclusive()
{
var lockId = Guid.NewGuid().ToString();
using (var readWriteLock1 = new TinyReadWriteLock(lockId, 2))
using (var readWriteLock2 = new TinyReadWriteLock(lockId, 2))
{
readWriteLock1.AcquireWriteLock();
Task.Factory.StartNew(() => readWriteLock2.AcquireWriteLock());
Thread.Sleep(10);
Assert.True(readWriteLock1.IsWriterLockHeld);
Assert.False(readWriteLock2.IsWriterLockHeld);
readWriteLock1.ReleaseWriteLock();
Thread.Sleep(10);
Assert.False(readWriteLock1.IsWriterLockHeld);
Assert.True(readWriteLock2.IsWriterLockHeld);
}
}
public void Calling_AcquireWriteLock_then_AquireReadLock_should_wait_for_other_lock()
{
var lockId = Guid.NewGuid().ToString();
using var readWriteLock1 = new TinyReadWriteLock(lockId, 2);
using var readWriteLock2 = new TinyReadWriteLock(lockId, 2);
readWriteLock1.AcquireWriteLock();
var readLockTask = Task.Run(() => readWriteLock2.AcquireReadLock());
WaitForTaskToStart(readLockTask);
Assert.True(readWriteLock1.IsWriterLockHeld);
Assert.False(readWriteLock2.IsReaderLockHeld);
readWriteLock1.ReleaseWriteLock();
readLockTask.Wait();
Assert.False(readWriteLock1.IsWriterLockHeld);
Assert.True(readWriteLock2.IsReaderLockHeld);
}