public void NestedTransactionAndRollback()
{
var needleA = Transact.CreateNeedle(5);
var needleB = Transact.CreateNeedle(1);
var thread = new Thread(() =>
{
using (var transaction = new Transact())
{
needleB.Value = 2;
transaction.Commit();
using (var transact = new Transact())
{
needleA.Value = 9;
Assert.AreEqual(9, needleA.Value);
Assert.AreEqual(2, needleB.Value);
transact.Commit();
}
Assert.AreEqual(9, needleA.Value);
Assert.AreEqual(2, needleB.Value);
transaction.Rollback();
Assert.AreEqual(5, needleA.Value);
Assert.AreEqual(2, needleB.Value);
using (new Transact())
{
needleA.Value = 13;
Assert.AreEqual(13, needleA.Value);
Assert.AreEqual(2, needleB.Value);
transaction.Rollback();
Assert.AreEqual(5, needleA.Value);
Assert.AreEqual(2, needleB.Value);
}
needleA.Value = 15;
transaction.Commit();
}
});
thread.Start();
thread.Join();
Assert.AreEqual(15, needleA.Value);
Assert.AreEqual(2, needleB.Value);
}
public void ReadonlyTransaction() // TODO: Review
{
using (var handle = new ManualResetEvent(false))
{
int[] count = { 0, 0 };
var needle = Transact.CreateNeedle(5);
Assert.AreEqual(needle.Value, 5);
ThreadPool.QueueUserWorkItem
(
_ =>
{
using (var transact = new Transact())
{
Interlocked.Increment(ref count[0]);
handle.WaitOne();
// This one only reads
GC.KeepAlive(needle.Value);
transact.Commit();
Interlocked.Increment(ref count[1]);
}
}
);
ThreadPool.QueueUserWorkItem
(
_ =>
{
using (var transact = new Transact())
{
Interlocked.Increment(ref count[0]);
handle.WaitOne();
needle.Value += 5;
transact.Commit();
Interlocked.Increment(ref count[1]);
}
}
);
while (Thread.VolatileRead(ref count[0]) != 2)
{
Thread.Sleep(0);
}
handle.Set();
while (Thread.VolatileRead(ref count[1]) != 2)
{
Thread.Sleep(0);
}
// There is no reason for failure
Assert.IsTrue(needle.Value == 10);
handle.Close();
}
}
public void NoRaceCondition() // TODO: Review
{
using (var handle = new ManualResetEvent(false))
{
int[] count = { 0, 0 };
var needleA = Transact.CreateNeedle(5);
var needleB = Transact.CreateNeedle(5);
Assert.AreEqual(needleA.Value, 5);
Assert.AreEqual(needleB.Value, 5);
ThreadPool.QueueUserWorkItem
(
_ =>
{
using (var transact = new Transact())
{
Interlocked.Increment(ref count[0]);
handle.WaitOne();
needleA.Value += 2;
transact.Commit();
}
Interlocked.Increment(ref count[1]);
}
);
ThreadPool.QueueUserWorkItem
(
_ =>
{
using (var transact = new Transact())
{
Interlocked.Increment(ref count[0]);
handle.WaitOne();
needleB.Value += 5;
transact.Commit();
}
Interlocked.Increment(ref count[1]);
}
);
global::Theraot.Threading.ThreadingHelper.SpinWaitUntil(ref count[0], 2);
handle.Set();
global::Theraot.Threading.ThreadingHelper.SpinWaitUntil(ref count[1], 2);
// Both
Assert.AreEqual(7, needleA.Value);
Assert.AreEqual(10, needleB.Value);
handle.Close();
}
}
public void Rollback()
{
var needleA = Transact.CreateNeedle(5);
var needleB = Transact.CreateNeedle(5);
try
{
using (var transact = new Transact())
{
const int Movement = 2;
needleA.Value += Movement;
ThrowException();
// Really, it is evident this code will not run
needleB.Value -= Movement;
transact.Commit();
}
}
catch (Exception exception)
{
// Catch'em all
GC.KeepAlive(exception);
}
// We did not commit
Assert.AreEqual(5, needleA.Value);
Assert.AreEqual(5, needleB.Value);
//---
using (var transact = new Transact())
{
needleA.Value = 9;
Assert.AreEqual(9, needleA.Value);
Assert.AreEqual(5, needleB.Value);
transact.Rollback();
Assert.AreEqual(5, needleA.Value);
Assert.AreEqual(5, needleB.Value);
}
// We did rollback
Assert.AreEqual(5, needleA.Value);
Assert.AreEqual(5, needleB.Value);
using (var transact = new Transact())
{
needleA.Value = 9;
Assert.AreEqual(9, needleA.Value);
Assert.AreEqual(5, needleB.Value);
transact.Rollback();
Assert.AreEqual(5, needleA.Value);
Assert.AreEqual(5, needleB.Value);
needleA.Value = 11;
Assert.AreEqual(11, needleA.Value);
Assert.AreEqual(5, needleB.Value);
transact.Commit();
}
// We did rollback and commit again
Assert.AreEqual(11, needleA.Value);
Assert.AreEqual(5, needleB.Value);
}
public void AbsentTransaction()
{
var needle = Transact.CreateNeedle(5);
Assert.AreEqual(5, needle.Value);
}