CoolVLViewer/indra/llmessage/llxfer.h

/**
 * @file llxfer.h
 * @brief definition of LLXfer class for a single xfer
 *
 * $LicenseInfo:firstyear=2001&license=viewergpl$
 *
 * Copyright (c) 2001-2009, Linden Research, Inc.
 *
 * Second Life Viewer Source Code
 * The source code in this file ("Source Code") is provided by Linden Lab
 * to you under the terms of the GNU General Public License, version 2.0
 * ("GPL"), unless you have obtained a separate licensing agreement
 * ("Other License"), formally executed by you and Linden Lab.  Terms of
 * the GPL can be found in doc/GPL-license.txt in this distribution, or
 * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
 *
 * There are special exceptions to the terms and conditions of the GPL as
 * it is applied to this Source Code. View the full text of the exception
 * in the file doc/FLOSS-exception.txt in this software distribution, or
 * online at
 * http://secondlifegrid.net/programs/open_source/licensing/flossexception
 *
 * By copying, modifying or distributing this software, you acknowledge
 * that you have read and understood your obligations described above,
 * and agree to abide by those obligations.
 *
 * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
 * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
 * COMPLETENESS OR PERFORMANCE.
 * $/LicenseInfo$
 */

#ifndef LL_LLXFER_H
#define LL_LLXFER_H

#include "llextendedstatus.h"
#include "lltimer.h"
#include "llmessage.h"

// Size of chunks read from/written to disk
constexpr U32 LL_MAX_XFER_FILE_BUFFER	= 65536;

constexpr S32 LL_XFER_LARGE_PAYLOAD		= 7680;
constexpr S32 LL_ERR_FILE_EMPTY			= -44;
constexpr int LL_ERR_FILE_NOT_FOUND		= -43;
constexpr int LL_ERR_CANNOT_OPEN_FILE	= -42;
constexpr int LL_ERR_EOF				= -39;

typedef enum ELLXferStatus {
	e_LL_XFER_UNINITIALIZED,
	e_LL_XFER_REGISTERED,	// a buffer which has been registered as available for a request
	e_LL_XFER_PENDING,		// a transfer which has been requested but is waiting for a free slot
	e_LL_XFER_IN_PROGRESS,
	e_LL_XFER_COMPLETE,
	e_LL_XFER_ABORTED,
	e_LL_XFER_NONE
} ELLXferStatus;

class LLXfer
{
protected:
	LOG_CLASS(LLXfer);

public:
	LLXfer(S32 chunk_size);
	virtual ~LLXfer();

	void init(S32 chunk_size);
	virtual void cleanup();

	virtual S32 startSend(U64 xfer_id, const LLHost& remote_host);
	virtual void closeFileHandle();
	virtual S32 reopenFileHandle();
	virtual void sendPacket(S32 packet_num);
	virtual void sendNextPacket();
	virtual void resendLastPacket();
	virtual S32 processEOF();
	virtual S32 startDownload();
	virtual S32 receiveData(char* datap, S32 data_size);
	virtual void abort(S32);

	virtual S32 suck(S32 start_position);
	virtual S32 flush();

	virtual S32 encodePacketNum(S32 packet_num, bool is_eof);
	virtual void setXferSize(S32 data_size);
	virtual S32  getMaxBufferSize();

	virtual std::string getFileName();

	virtual U32 getXferTypeTag();

	friend std::ostream& operator<<(std::ostream& os, LLXfer& hh);

public:
	static constexpr U32 XFER_FILE = 1;
	static constexpr U32 XFER_VFILE = 2;
	static constexpr U32 XFER_MEM = 3;

	U64					mID;
	S32					mPacketNum;

	LLHost				mRemoteHost;
	S32					mXferSize;

	char*				mBuffer;
	// Size of valid data, not actual allocated buffer size:
	U32					mBufferLength;
	U32					mBufferStartOffset;
	bool				mBufferContainsEOF;

	ELLXferStatus		mStatus;

	void				(*mCallback)(void**, S32, LLExtStat);
	void**				mCallbackDataHandle;
	S32					mCallbackResult;

	LLTimer				ACKTimer;
	S32					mRetries;

	bool				mWaitingForACK;

protected:
	S32					mChunkSize;
};

#endif