// 获得锁对象
RecordLock GetLock(string strID,
bool bAutoCreate = true)
{
// 加写锁
this._lockForWrite(m_nLockTimeout);
try
{
RecordLock reclock = (RecordLock)RecordLocks[strID];
if (reclock == null)
{
if (bAutoCreate == true)
{
reclock = new RecordLock();
reclock.m_strID = strID;
RecordLocks.Add(strID, reclock);
}
else
{
return(null);
}
}
Interlocked.Increment(ref reclock.m_nUseCount);
// Debug.WriteLine("record lock count " + RecordLocks.Count);
return(reclock);
}
finally
{
this._unlockForWrite();
}
}
// 写锁定
public void LockForWrite(string strID,
int nTimeOut)
{
RecordLock reclock = GetLock(strID);
// Interlocked.Increment(ref reclock.m_nUseCount);
// 加写锁
try
{
reclock._lockForWrite(nTimeOut);
}
catch (Exception ex)
{
Interlocked.Decrement(ref reclock.m_nUseCount);
// 是否还要删除?
throw ex;
}
}
public void UnlockForWrite(string strID)
{
RecordLock reclock = GetLock(strID, false);
if (reclock == null)
{
throw new Exception("id '" + strID + "' 没有找到对应的记录锁");
}
try
{
reclock._unlockForWrite();
}
finally
{
Interlocked.Decrement(ref reclock.m_nUseCount);
Interlocked.Decrement(ref reclock.m_nUseCount);
TryRemoveLock(reclock);
}
}
// 试图移走锁对象
// 应当在RecordLock:m_lock解锁以后进行
void TryRemoveLock(RecordLock reclock)
{
// 加写锁
this._lockForWrite(m_nLockTimeout);
try
{
int nRet = Interlocked.Increment(ref reclock.m_nUseCount);
if (nRet == 1) // 说明增量以前为0
{
this.RecordLocks.Remove(reclock.m_strID);
}
else
{
Interlocked.Decrement(ref reclock.m_nUseCount);
}
}
finally
{
this._unlockForWrite();
}
}
// 输出到文本
public string DumpText()
{
// 加读锁
this._lockForRead(m_nLockTimeout);
try
{
string strResult = "";
foreach (string key in RecordLocks.Keys)
{
RecordLock onelock = (RecordLock)this.RecordLocks[key];
strResult += "id='" + onelock.m_strID + "' usecount='" + Convert.ToString(onelock.m_nUseCount) + "' hashcode='" + onelock.GetLockHashCode() + "'\r\n";
}
return(strResult);
}
finally
{
this._unlockForRead();
}
}