public void NestedWriteLocking2()
{
var d = new SnapDictionary <int, string>();
d.Test.CollectAuto = false;
Assert.AreEqual(0, d.CreateSnapshot().Gen);
// scope context: writers enlist
var scopeContext = new ScopeContext();
var scopeProvider = GetScopeProvider(scopeContext);
using (var w1 = d.GetScopedWriteLock(scopeProvider))
{
// This one is interesting, although we don't allow recursive locks, since this is
// using the same ScopeContext/key, the lock acquisition is only done once
using (var w2 = d.GetScopedWriteLock(scopeProvider))
{
Assert.AreSame(w1, w2);
d.SetLocked(1, "one");
}
}
}
public void WriteLocking()
{
var d = new SnapDictionary <int, string>();
d.Test.CollectAuto = false;
// gen 1
d.Set(1, "one");
Assert.AreEqual(1, d.Test.GetValues(1).Length);
Assert.AreEqual(1, d.Test.LiveGen);
Assert.IsTrue(d.Test.NextGen);
var s1 = d.CreateSnapshot();
Assert.AreEqual(1, s1.Gen);
Assert.AreEqual(1, d.Test.LiveGen);
Assert.IsFalse(d.Test.NextGen);
Assert.AreEqual("one", s1.Get(1));
// gen 2
Assert.AreEqual(1, d.Test.GetValues(1).Length);
d.Set(1, "uno");
Assert.AreEqual(2, d.Test.GetValues(1).Length);
Assert.AreEqual(2, d.Test.LiveGen);
Assert.IsTrue(d.Test.NextGen);
var s2 = d.CreateSnapshot();
Assert.AreEqual(2, s2.Gen);
Assert.AreEqual(2, d.Test.LiveGen);
Assert.IsFalse(d.Test.NextGen);
Assert.AreEqual("uno", s2.Get(1));
using (d.GetScopedWriteLock(GetScopeProvider()))
{
// gen 3
Assert.AreEqual(2, d.Test.GetValues(1).Length);
d.SetLocked(1, "ein");
Assert.AreEqual(3, d.Test.GetValues(1).Length);
Assert.AreEqual(3, d.Test.LiveGen);
Assert.IsTrue(d.Test.NextGen);
var s3 = d.CreateSnapshot();
Assert.AreEqual(2, s3.Gen);
Assert.AreEqual(3, d.Test.LiveGen);
Assert.IsTrue(d.Test.NextGen); // has NOT changed when (non) creating snapshot
Assert.AreEqual("uno", s3.Get(1));
}
var s4 = d.CreateSnapshot();
Assert.AreEqual(3, s4.Gen);
Assert.AreEqual(3, d.Test.LiveGen);
Assert.IsFalse(d.Test.NextGen);
Assert.AreEqual("ein", s4.Get(1));
}
internal static void Set <TKey, TValue>(this SnapDictionary <TKey, TValue> d, TKey key, TValue value)
where TValue : class
{
using (d.GetScopedWriteLock(GetScopeProvider()))
{
d.SetLocked(key, value);
}
}
public void ScopeLocking1()
{
var d = new SnapDictionary <int, string>();
d.Test.CollectAuto = false;
// gen 1
d.Set(1, "one");
var s1 = d.CreateSnapshot();
Assert.AreEqual(1, s1.Gen);
Assert.AreEqual("one", s1.Get(1));
d.Set(1, "uno");
var s2 = d.CreateSnapshot();
Assert.AreEqual(2, s2.Gen);
Assert.AreEqual("uno", s2.Get(1));
var scopeContext = new ScopeContext();
var scopeProvider = GetScopeProvider(scopeContext);
using (d.GetScopedWriteLock(scopeProvider))
{
// creating a snapshot in a write-lock does NOT return the "current" content
// it uses the previous snapshot, so new snapshot created only on release
d.SetLocked(1, "ein");
var s3 = d.CreateSnapshot();
Assert.AreEqual(2, s3.Gen);
Assert.AreEqual("uno", s3.Get(1));
// but live snapshot contains changes
var ls = d.Test.LiveSnapshot;
Assert.AreEqual("ein", ls.Get(1));
Assert.AreEqual(3, ls.Gen);
}
var s4 = d.CreateSnapshot();
Assert.AreEqual(2, s4.Gen);
Assert.AreEqual("uno", s4.Get(1));
scopeContext.ScopeExit(true);
var s5 = d.CreateSnapshot();
Assert.AreEqual(3, s5.Gen);
Assert.AreEqual("ein", s5.Get(1));
}
public void DontPanic()
{
var d = new SnapDictionary <int, string>();
d.Test.CollectAuto = false;
Assert.IsNull(d.Test.GenObj);
// gen 1
d.Set(1, "one");
Assert.IsTrue(d.Test.NextGen);
Assert.AreEqual(1, d.Test.LiveGen);
Assert.IsNull(d.Test.GenObj);
var s1 = d.CreateSnapshot();
Assert.IsFalse(d.Test.NextGen);
Assert.AreEqual(1, d.Test.LiveGen);
Assert.IsNotNull(d.Test.GenObj);
Assert.AreEqual(1, d.Test.GenObj.Gen);
Assert.AreEqual(1, s1.Gen);
Assert.AreEqual("one", s1.Get(1));
d.Set(1, "uno");
Assert.IsTrue(d.Test.NextGen);
Assert.AreEqual(2, d.Test.LiveGen);
Assert.IsNotNull(d.Test.GenObj);
Assert.AreEqual(1, d.Test.GenObj.Gen);
var scopeContext = new ScopeContext();
var scopeProvider = GetScopeProvider(scopeContext);
// scopeProvider.Context == scopeContext -> writer is scoped
// writer is scope contextual and scoped
// when disposed, nothing happens
// when the context exists, the writer is released
using (d.GetScopedWriteLock(scopeProvider))
{
d.SetLocked(1, "ein");
Assert.IsTrue(d.Test.NextGen);
Assert.AreEqual(3, d.Test.LiveGen);
Assert.IsNotNull(d.Test.GenObj);
Assert.AreEqual(2, d.Test.GenObj.Gen);
}
// writer has not released
Assert.IsTrue(d.Test.IsLocked);
Assert.IsNotNull(d.Test.GenObj);
Assert.AreEqual(2, d.Test.GenObj.Gen);
// nothing changed
Assert.IsTrue(d.Test.NextGen);
Assert.AreEqual(3, d.Test.LiveGen);
// panic!
var s2 = d.CreateSnapshot();
Assert.IsTrue(d.Test.IsLocked);
Assert.IsNotNull(d.Test.GenObj);
Assert.AreEqual(2, d.Test.GenObj.Gen);
Assert.AreEqual(3, d.Test.LiveGen);
Assert.IsTrue(d.Test.NextGen);
// release writer
scopeContext.ScopeExit(true);
Assert.IsFalse(d.Test.IsLocked);
Assert.IsNotNull(d.Test.GenObj);
Assert.AreEqual(2, d.Test.GenObj.Gen);
Assert.AreEqual(3, d.Test.LiveGen);
Assert.IsTrue(d.Test.NextGen);
var s3 = d.CreateSnapshot();
Assert.IsFalse(d.Test.IsLocked);
Assert.IsNotNull(d.Test.GenObj);
Assert.AreEqual(3, d.Test.GenObj.Gen);
Assert.AreEqual(3, d.Test.LiveGen);
Assert.IsFalse(d.Test.NextGen);
}
public void ScopeLocking2()
{
var d = new SnapDictionary <int, string>();
var t = d.Test;
t.CollectAuto = false;
// gen 1
d.Set(1, "one");
var s1 = d.CreateSnapshot();
Assert.AreEqual(1, s1.Gen);
Assert.AreEqual("one", s1.Get(1));
d.Set(1, "uno");
var s2 = d.CreateSnapshot();
Assert.AreEqual(2, s2.Gen);
Assert.AreEqual("uno", s2.Get(1));
Assert.AreEqual(2, t.LiveGen);
Assert.IsFalse(t.NextGen);
var scopeContext = new ScopeContext();
var scopeProvider = GetScopeProvider(scopeContext);
using (d.GetScopedWriteLock(scopeProvider))
{
// creating a snapshot in a write-lock does NOT return the "current" content
// it uses the previous snapshot, so new snapshot created only on release
d.SetLocked(1, "ein");
var s3 = d.CreateSnapshot();
Assert.AreEqual(2, s3.Gen);
Assert.AreEqual("uno", s3.Get(1));
// we made some changes, so a next gen is required
Assert.AreEqual(3, t.LiveGen);
Assert.IsTrue(t.NextGen);
Assert.IsTrue(t.IsLocked);
// but live snapshot contains changes
var ls = t.LiveSnapshot;
Assert.AreEqual("ein", ls.Get(1));
Assert.AreEqual(3, ls.Gen);
}
// nothing is committed until scope exits
Assert.AreEqual(3, t.LiveGen);
Assert.IsTrue(t.NextGen);
Assert.IsTrue(t.IsLocked);
// no changes until exit
var s4 = d.CreateSnapshot();
Assert.AreEqual(2, s4.Gen);
Assert.AreEqual("uno", s4.Get(1));
scopeContext.ScopeExit(false);
// now things have changed
Assert.AreEqual(2, t.LiveGen);
Assert.IsFalse(t.NextGen);
Assert.IsFalse(t.IsLocked);
// no changes since not completed
var s5 = d.CreateSnapshot();
Assert.AreEqual(2, s5.Gen);
Assert.AreEqual("uno", s5.Get(1));
}