CachedResponse ICachedClient.Execute(CachedRequest request)
{
var batch = new CachedRequest[1] { request };
var result = new CachedResponse[1] { new CachedResponse(request) };
ExecuteBatch(batch, result);
return result[0];
}
CachedResponse[] ExecuteBatch(CachedRequest[] batch)
{
var response = new CachedResponse[batch.Length];
for (int i = 0; i < batch.Length; i++)
response[i] = new CachedResponse(batch[i]);
ExecuteBatch(batch, response);
return response;
}
private int CalcStackStize(CachedRequest[] batch)
{
var bsize = 0;
foreach(var request in batch)
{
var key = request.Key;
bsize += _align8(sizeof(DataKey) + (key == null ? 0 : key.Length));
}
return bsize;
}
private void Encode(CachedRequest request, int opaque)
{
if (request == null)
throw new ArgumentNullException();
var opc = opaque == 0 ? request.Opcode : (int)QuietMap[request.Opcode];
_packet.Reset(opc);
if (opaque != 0) _packet.Opaque = (uint)opaque;
var key = request.Key;
switch ((Opcode)request.Opcode)
{
case Opcode.Get:
case Opcode.GetQ:
case Opcode.GetK:
case Opcode.GetKq:
case Opcode.Delete:
case Opcode.DeleteQ:
_packet.KeyLength = _packet.TotalBody = (uint)key.Length;
_packet.WriteTo(_output);
_output.WriteBytes(key, 0, key.Length);
break;
case Opcode.Set:
case Opcode.SetQ:
case Opcode.Add:
case Opcode.AddQ:
case Opcode.Replace:
case Opcode.ReplaceQ:
_packet.KeyLength = (uint)key.Length;
_packet.ExtLength = 8;
var data = request.Data;
var vsz = data != null ? data.Length : 0;
_packet.TotalBody = (uint)(key.Length + vsz + 8);
if (request.Cas != 0) _packet.Cas = request.Cas;
_packet.WriteTo(_output);
_output.WriteB32BE((uint)request.Flags);
_output.WriteB32BE(request.Expires);
_output.WriteBytes(key, 0, key.Length);
if (vsz > 0) _output.WriteBytes(data, 0, vsz);
break;
case Opcode.Noop:
case Opcode.Version:
case Opcode.Quit:
case Opcode.QuitQ:
_packet.WriteTo(_output);
break;
case Opcode.Flush:
case Opcode.FlushQ:
var expires = request.HasExpires;
if (expires) _packet.ExtLength = _packet.TotalBody = 4;
_packet.WriteTo(_output);
if (expires) _output.WriteB32BE(request.Expires);
break;
case Opcode.Inc:
case Opcode.IncQ:
case Opcode.Dec:
case Opcode.DecQ:
_packet.ExtLength = 20;
_packet.KeyLength = (uint)key.Length;
_packet.TotalBody = (uint)(20 + key.Length);
if (request.HasCas) _packet.Cas = request.Cas;
_packet.WriteTo(_output);
_output.WriteB64BE(request.Delta);
_output.WriteB64BE(request.Flags);
_output.WriteB32BE(request.Expires);
_output.WriteBytes(key, 0, key.Length);
break;
case Opcode.Append:
case Opcode.AppendQ:
case Opcode.Prepend:
case Opcode.PrependQ:
_packet.KeyLength = (uint)key.Length;
var pdata = request.Data;
_packet.TotalBody = (uint)(key.Length + pdata.Length);
if (request.Cas != 0) _packet.Cas = request.Cas;
_packet.WriteTo(_output);
_output.WriteBytes(key, 0, key.Length);
_output.WriteBytes(pdata, 0, pdata.Length);
break;
default:
throw new NotSupportedException();
}
}
public CachedResponse(CachedRequest request)
{
Request = request;
}
void IChannelSync.Dispatch(Message request, Message response)
{
var batch = new CachedRequest[1] { request as CachedRequest };
var result = new CachedResponse[1] { response as CachedResponse };
ExecuteBatch(batch, result);
}
public void ExecuteBatch(CachedRequest[] batch, CachedResponse[] result)
{
if (batch == null || batch.Length == 0)
return;
// calculate transient memory space requirements.
var bsize = CalcStackStize(batch);
uint opaque = 1;
DataKey* dataKey = null, last = null;
var db = stackalloc byte[bsize];
var cp = db;
// copy requests data into memcached protocol format.
foreach(var request in batch)
{
var dk = (DataKey*)cp;
_init_dk(dk, request.Opcode);
var key = request.Key;
if (key != null)
{
_set_key(dk, key, key.Length);
cp += _align8(sizeof(DataKey) + key.Length);
}
else cp += sizeof(DataKey);
dk->opaque = opaque++;
dk = SetDataKey(dk, request);
// append new request to dataKey list
if (last == null) dataKey = dk;
else last->next = dk;
last = dk;
}
// execute built-up request chain against cache.
ExecuteBatch(dataKey, 0);
// move cached results into responses fields.
foreach(var response in result)
{
// copy response data from datakey into message.
var status = dataKey->status;
response.Status = 0;
switch (status)
{
case 0:
response.Cas = dataKey->cas;
response.Flags = Pbs.SwapBytes(dataKey->flags);
var dtsize = dataKey->ValSize;
if (dtsize > 0)
{
response.Data = new byte[dtsize];
_memcopy(response.Data, dataKey->val_addr, dtsize);
}
break;
case iSpecialCommand:
if (IncDecOps.Has(dataKey->opcode))
{
response.Cas = dataKey->cas;
response.Counter = (ulong)dataKey->longval;
}
else
{
//todo: support for more stats.
if (dataKey->opcode == (byte)Opcode.Version)
response.Data = sLocalVersion;
}
break;
default:
response.Status = status;
break;
}
// advance datakey in sync with responses list.
dataKey = dataKey->next;
}
}
private DataKey* SetDataKey(DataKey* dk, CachedRequest rqs)
{
dk->cas = rqs.Cas;
dk->etime = rqs.Expires;
dk->flags = Pbs.SwapBytes((uint)rqs.Flags);
if (!IncDecOps.Has(dk->opcode))
{
var data = rqs.Data;
var size = rqs.DataCount;
if (size > 0)
{
dk->ValSize = size;
dk->val_addr = AllocValueMem(size);
fixed (byte* ds = data)
dk->AppendValue(ds + rqs.DataOffset, size, 0);
}
}
else
{
dk->longval = (long)rqs.Delta;
dk->def_val = (long)rqs.Flags;
}
return dk;
}
