Files
opensim/OpenSim/Framework/ExpiringCacheOS.cs
2025-10-18 22:07:51 +01:00

392 lines
13 KiB
C#

/*
* Copyright (c) Contributors, http://opensimulator.org/
* See CONTRIBUTORS.TXT for a full list of copyright holders.
*
* - Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* - Neither the name of the openmetaverse.org nor the names
* of its contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
// this is a lighter alternative to libomv, no sliding option
using System;
using System.Threading;
using System.Collections.Generic;
using Timer = System.Threading.Timer;
using System.Runtime.InteropServices;
namespace OpenSim.Framework
{
public sealed class ExpiringCacheOS<TKey1, TValue1> : IDisposable
{
private const int MINEXPIRECHECK = 500;
private Timer m_purgeTimer;
private ReaderWriterLockSlim m_rwLock;
private readonly Dictionary<TKey1, int> m_expireControl;
private readonly Dictionary<TKey1, TValue1> m_values;
TValue1[] valuesArrayCache = null;
private readonly double m_startTS;
private readonly int m_expire;
public ExpiringCacheOS()
{
m_expireControl = new Dictionary<TKey1, int>();
m_values = new Dictionary<TKey1, TValue1>();
m_rwLock = new ReaderWriterLockSlim();
m_expire = MINEXPIRECHECK;
m_startTS = Util.GetTimeStampMS();
}
public ExpiringCacheOS(int expireCheckTimeinMS)
{
m_expireControl = new Dictionary<TKey1, int>();
m_values = new Dictionary<TKey1, TValue1>();
m_rwLock = new ReaderWriterLockSlim();
m_startTS = Util.GetTimeStampMS();
m_expire = (expireCheckTimeinMS > MINEXPIRECHECK) ? m_expire = expireCheckTimeinMS : MINEXPIRECHECK;
}
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
private void CheckTimer()
{
m_purgeTimer ??= new Timer(Purge, null, m_expire, Timeout.Infinite);
}
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
private void DisposeTimer()
{
if (m_purgeTimer != null)
{
m_purgeTimer.Dispose();
m_purgeTimer = null;
}
}
~ExpiringCacheOS()
{
Dispose(false);
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
private void Dispose(bool disposing)
{
if (m_rwLock != null)
{
DisposeTimer();
m_rwLock.Dispose();
m_rwLock = null;
}
}
private void Purge(object ignored)
{
m_rwLock.EnterUpgradeableReadLock();
try
{
if (m_expireControl.Count == 0)
{
DisposeTimer();
return;
}
int now = (int)(Util.GetTimeStampMS() - m_startTS);
List<TKey1> expired = new List<TKey1>(m_expireControl.Count);
foreach(KeyValuePair<TKey1, int> kvp in m_expireControl)
{
int expire = kvp.Value;
if(expire > 0 && expire < now)
expired.Add(kvp.Key);
}
if(expired.Count > 0)
{
m_rwLock.EnterWriteLock();
try
{
valuesArrayCache = null;
foreach (TKey1 key in expired)
{
m_expireControl.Remove(key);
m_values.Remove(key);
}
}
finally { m_rwLock.ExitWriteLock(); }
if (m_expireControl.Count == 0)
DisposeTimer();
else
m_purgeTimer.Change(m_expire, Timeout.Infinite);
}
else
m_purgeTimer.Change(m_expire, Timeout.Infinite);
}
finally { m_rwLock.ExitUpgradeableReadLock(); }
}
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
public void AddOrUpdate(TKey1 key, TValue1 val)
{
Add(key, val);
}
public void Add(TKey1 key, TValue1 val)
{
int now = (int)(Util.GetTimeStampMS() - m_startTS) + m_expire;
m_rwLock.EnterWriteLock();
try
{
m_expireControl[key] = now;
m_values[key] = val;
valuesArrayCache = null;
CheckTimer();
}
finally { m_rwLock.ExitWriteLock(); }
}
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
public void AddOrUpdate(TKey1 key, TValue1 val, int expireSeconds)
{
Add(key, val, expireSeconds * 1000);
}
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
public void AddOrUpdate(TKey1 key, TValue1 val, double expireSeconds)
{
Add(key, val, (int)(expireSeconds * 1000));
}
public void Add(TKey1 key, TValue1 val, int expireMS)
{
int now;
if (expireMS > 0)
{
expireMS = (expireMS > m_expire) ? expireMS : m_expire;
now = (int)(Util.GetTimeStampMS() - m_startTS) + expireMS;
}
else
now = int.MinValue;
m_rwLock.EnterWriteLock();
try
{
m_expireControl[key] = now;
m_values[key] = val;
valuesArrayCache = null;
CheckTimer();
}
finally { m_rwLock.ExitWriteLock(); }
}
public bool Remove(TKey1 key)
{
m_rwLock.EnterWriteLock();
try
{
bool success = m_expireControl.Remove(key);
success |= m_values.Remove(key);
if(success)
valuesArrayCache = null;
if (m_expireControl.Count == 0)
DisposeTimer();
return success;
}
finally { m_rwLock.ExitWriteLock(); }
}
public void Clear()
{
m_rwLock.EnterWriteLock();
try
{
DisposeTimer();
m_expireControl.Clear();
m_values.Clear();
valuesArrayCache = null;
}
finally { m_rwLock.ExitWriteLock(); }
}
public int Count
{
get { return m_expireControl.Count; }
}
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
public bool Contains(TKey1 key)
{
return ContainsKey(key);
}
public bool ContainsKey(TKey1 key)
{
m_rwLock.EnterReadLock();
try
{
return m_expireControl.ContainsKey(key);
}
finally { m_rwLock.ExitReadLock(); }
}
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
public bool Contains(TKey1 key, int expireMS)
{
return ContainsKey(key, expireMS);
}
public bool ContainsKey(TKey1 key, int expireMS)
{
m_rwLock.EnterUpgradeableReadLock();
try
{
if(m_expireControl.ContainsKey(key))
{
m_rwLock.EnterWriteLock();
try
{
int now;
if(expireMS > 0)
{
expireMS = (expireMS > m_expire) ? expireMS : m_expire;
now = (int)(Util.GetTimeStampMS() - m_startTS) + expireMS;
}
else
now = int.MinValue;
m_expireControl[key] = now;
return true;
}
finally { m_rwLock.ExitWriteLock(); }
}
return false;
}
finally { m_rwLock.ExitUpgradeableReadLock(); }
}
public bool TryGetValue(TKey1 key, out TValue1 value)
{
m_rwLock.EnterReadLock();
try
{
return m_values.TryGetValue(key, out value);
}
finally { m_rwLock.ExitReadLock(); }
}
public bool TryGetValue(TKey1 key, int expireMS, out TValue1 value)
{
m_rwLock.EnterUpgradeableReadLock();
try
{
if(m_values.TryGetValue(key, out value))
{
m_rwLock.EnterWriteLock();
try
{
int now;
if(expireMS > 0)
{
expireMS = (expireMS > m_expire) ? expireMS : m_expire;
now = (int)(Util.GetTimeStampMS() - m_startTS) + expireMS;
}
else
now = int.MinValue;
m_expireControl[key] = now;
return true;
}
finally { m_rwLock.ExitWriteLock(); }
}
return false;
}
finally { m_rwLock.ExitUpgradeableReadLock(); }
}
public ref TValue1 TryGetOrDefaultValue(TKey1 key, out bool existed)
{
m_rwLock.ExitUpgradeableReadLock();
try
{
return ref CollectionsMarshal.GetValueRefOrAddDefault(m_values, key, out existed);
}
finally { m_rwLock.ExitUpgradeableReadLock(); }
}
public ref TValue1 TryGetOrDefaultValue(TKey1 key, int expireMS, out bool existed)
{
m_rwLock.EnterWriteLock();
try
{
ref TValue1 ret = ref CollectionsMarshal.GetValueRefOrAddDefault(m_values, key, out existed);
int now;
if (expireMS > 0)
{
expireMS = (expireMS > m_expire) ? expireMS : m_expire;
now = (int)(Util.GetTimeStampMS() - m_startTS) + expireMS;
}
else
now = int.MinValue;
m_expireControl[key] = now;
return ref ret;
}
finally { m_rwLock.EnterWriteLock(); }
}
public TValue1[] Values
{
get
{
m_rwLock.EnterUpgradeableReadLock();
try
{
if(valuesArrayCache == null)
{
valuesArrayCache = new TValue1[m_values.Count];
m_values.Values.CopyTo(valuesArrayCache, 0);
}
return valuesArrayCache;
}
finally { m_rwLock.ExitUpgradeableReadLock(); }
}
}
/*
public ICollection<TKey1> Keys
{
get
{
m_rwLock.EnterUpgradeableReadLock();
try
{
return m_values.Keys;
}
finally { m_rwLock.ExitUpgradeableReadLock(); }
}
}
*/
}
}