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//------------------------------------------------------------------------------
// <copyright file="OdbcEnvironment.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
using System;
using System.Data;
using System.Data.Common;
using System.Threading;
namespace System.Data.Odbc {
sealed internal class OdbcEnvironment {
static private object _globalEnvironmentHandle;
static private object _globalEnvironmentHandleLock = new object();
private OdbcEnvironment () {} // default const.
static internal OdbcEnvironmentHandle GetGlobalEnvironmentHandle() {
OdbcEnvironmentHandle globalEnvironmentHandle = _globalEnvironmentHandle as OdbcEnvironmentHandle;
if(null == globalEnvironmentHandle) {
ADP.CheckVersionMDAC(true);
lock(_globalEnvironmentHandleLock) {
globalEnvironmentHandle = _globalEnvironmentHandle as OdbcEnvironmentHandle;
if(null == globalEnvironmentHandle) {
globalEnvironmentHandle = new OdbcEnvironmentHandle();
_globalEnvironmentHandle = globalEnvironmentHandle;
}
}
}
return globalEnvironmentHandle;
}
static internal void ReleaseObjectPool() {
object globalEnvironmentHandle = Interlocked.Exchange(ref _globalEnvironmentHandle, null);
if(null != globalEnvironmentHandle) {
(globalEnvironmentHandle as OdbcEnvironmentHandle).Dispose(); // internally refcounted so will happen correctly
}
}
}
}
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