/**
* @file llchainio.h
* @author Phoenix
* @date 2005-08-04
* @brief This class declares the interface for constructing io chains.
*
* $LicenseInfo:firstyear=2005&license=viewerlgpl$
* Second Life Viewer Source Code
* Copyright (C) 2010, Linden Research, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License only.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA
* $/LicenseInfo$
*/
#ifndef LL_LLCHAINIO_H
#define LL_LLCHAINIO_H
#include "llpumpio.h"
/**
* @class LLDeferredChain
* @brief This class allows easy addition of a chain which will sleep
* and then process another chain.
*/
class LLDeferredChain
{
public:
/**
* @brief Add a chain to a pump in a finite # of seconds
*
* @prarm pump The pump to work on.
* @prarm in_seconds The number of seconds from now when chain should start.
* @prarm chain The chain to add in in_seconds seconds.
* @prarm chain_timeout timeout for chain on the pump.
* @return Returns true if the operation was queued.
*/
static bool addToPump(
LLPumpIO* pump,
F32 in_seconds,
const LLPumpIO::chain_t& chain,
F32 chain_timeout);
};
/**
* @class LLChainIOFactory
* @brief This class is an abstract base class for building io chains.
*
* This declares an abstract base class for a chain factory. The
* factory is used to connect an input pipe to the first pipe in the
* chain, and an output pipe to the last pipe in the chain. This will
* allow easy construction for buffer based io like services to for
* API centered IO while abstracting the input and output to simple
* data passing.
* To use this class, you should derive a class which implements the
* build
method.
*/
class LLChainIOFactory
{
public:
// Constructor
LLChainIOFactory();
// Destructor
virtual ~LLChainIOFactory();
/**
* @brief Build the chian with in as the first and end as the last
*
* The caller of the LLChainIOFactory is responsible for managing
* the memory of the in pipe. All of the chains generated by the
* factory will be ref counted as usual, so the caller will also
* need to break the links in the chain.
* @param chain The chain which will have new pipes appended
* @param context A context for use by this factory if you choose
* @retrun Returns true if the call was successful.
*/
virtual bool build(LLPumpIO::chain_t& chain, LLSD context) const = 0;
protected:
};
/**
* @class LLSimpleIOFactory
* @brief Basic implementation for making a factory that returns a
* 'chain' of one object
*/
template
class LLSimpleIOFactory : public LLChainIOFactory
{
public:
virtual bool build(LLPumpIO::chain_t& chain, LLSD context) const
{
chain.push_back(LLIOPipe::ptr_t(new Pipe));
return true;
}
};
/**
* @class LLCloneIOFactory
* @brief Implementation for a facory which copies a particular pipe.
*/
template
class LLCloneIOFactory : public LLChainIOFactory
{
public:
LLCloneIOFactory(Pipe* original) :
mHandle(original),
mOriginal(original) {}
virtual bool build(LLPumpIO::chain_t& chain, LLSD context) const
{
chain.push_back(LLIOPipe::ptr_t(new Pipe(*mOriginal)));
return true;
}
protected:
LLIOPipe::ptr_t mHandle;
Pipe* mOriginal;
};
#endif // LL_LLCHAINIO_H