/** Swap the value held at key, and return the old value
* @param key the key to change the value of
* @param new_value the new value to set to
* @param cb the delegate to call at completion
*/
override public IAsyncResult BeginSwap(MemBlock key, MemBlock new_value, AsyncCallback cb,
object state)
{
MemBlock old_v = null;
lock ( _sync ) {
old_v = _ht[key] as MemBlock;
_ht[key] = new_value;
}
IAsyncResult r = new LhtAsResult(state, old_v);
cb(r);
return(r);
}
/** Begin a Read of a Key
* @param key the key to read
* @param result_cb the delegate to call when the read completes
*/
override public IAsyncResult BeginRead(MemBlock key, AsyncCallback cb,
object state)
{
MemBlock old_v = null;
lock ( _sync ) {
//We have to hold the lock to be consistent with CompareSwap and Swap
old_v = _ht[key] as MemBlock;
}
IAsyncResult r = new LhtAsResult(state, old_v);
cb(r);
return(r);
}
/** Begin a Compare-and-Swap operation
* @param key the key to change
* @param new_value the value to replace if the old value is given
* @param old_value the value we are checking for (may be null)
* @param cb the delegate to call on completion
* Note the swap succeeds if and only if the return value
* of EndCompareSwap == old_value
*/
override public IAsyncResult BeginCompareSwap(MemBlock key, MemBlock new_value,
MemBlock old_value, AsyncCallback cb,
object state)
{
MemBlock old_v = null;
lock ( _sync ) {
old_v = _ht[key] as MemBlock;
if ((old_v == null) && (old_value == null))
{
//Looks good:
_ht[key] = new_value;
}
else if (old_v.Equals(old_value))
{
//Use Equals method to check for equality
_ht[key] = new_value;
}
}
IAsyncResult r = new LhtAsResult(state, old_v);
cb(r);
return(r);
}
/** Swap the value held at key, and return the old value
* @param key the key to change the value of
* @param new_value the new value to set to
* @param cb the delegate to call at completion
*/
override public IAsyncResult BeginSwap(MemBlock key, MemBlock new_value, AsyncCallback cb,
object state) {
MemBlock old_v = null;
lock( _sync ) {
old_v = _ht[key] as MemBlock;
_ht[key] = new_value;
}
IAsyncResult r = new LhtAsResult(state, old_v);
cb(r);
return r;
}
/** Begin a Read of a Key
* @param key the key to read
* @param result_cb the delegate to call when the read completes
*/
override public IAsyncResult BeginRead(MemBlock key, AsyncCallback cb,
object state) {
MemBlock old_v = null;
lock( _sync ) {
//We have to hold the lock to be consistent with CompareSwap and Swap
old_v = _ht[key] as MemBlock;
}
IAsyncResult r = new LhtAsResult(state, old_v);
cb(r);
return r;
}
/** Begin a Compare-and-Swap operation
* @param key the key to change
* @param new_value the value to replace if the old value is given
* @param old_value the value we are checking for (may be null)
* @param cb the delegate to call on completion
* Note the swap succeeds if and only if the return value
* of EndCompareSwap == old_value
*/
override public IAsyncResult BeginCompareSwap(MemBlock key, MemBlock new_value,
MemBlock old_value, AsyncCallback cb,
object state) {
MemBlock old_v = null;
lock( _sync ) {
old_v = _ht[key] as MemBlock;
if ( (old_v == null) && (old_value == null)) {
//Looks good:
_ht[key] = new_value;
}
else if( old_v.Equals(old_value) ) {
//Use Equals method to check for equality
_ht[key] = new_value;
}
}
IAsyncResult r = new LhtAsResult(state, old_v);
cb(r);
return r;
}
/** End a Swap
* @return the old value held by the key
*/
override public MemBlock EndSwap(IAsyncResult r)
{
LhtAsResult res = (LhtAsResult)r;
return(res.Result);
}