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// This file is part of par2cmdline (a PAR 2.0 compatible file verification and
// repair tool). See http://parchive.sourceforge.net for details of PAR 2.0.
//
// Copyright (c) 2003 Peter Brian Clements
//
// par2cmdline is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// par2cmdline 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
#ifndef __RECOVERYPACKET_H__
#define __RECOVERYPACKET_H__
// The RecoveryPacket object is used to access a specific recovery
// packet within a recovery file (for when creating them, or using
// them during a repair operation).
// Because the actual recovery data for the packet may be large, the
// RecoveryPacket object only contains a copy of packet header and
// exponent value for the block and uses a DataBlock object for
// all accesses to the actual recovery data in the packet.
class RecoveryPacket
{
public:
RecoveryPacket(void);
~RecoveryPacket(void);
public:
// Create a recovery packet for a specified file.
void Create(DiskFile *diskfile, // Which file will the packet be stored in
u64 offset, // At what offset will the packet be stored
u64 blocksize, // How much recovery data will it contain
u32 exponent, // What exponent value will be used
const MD5Hash &setid); // What is the SetId
// Write some data to the recovery data block and update the recovery packet.
bool WriteData(u64 position, // Relative position within the data block
size_t size, // Size of data to write to block
const void *buffer); // Buffer containing the data to write
// Finish computing the hash of the recovery packet and write the header to disk.
bool WriteHeader(void);
public:
// Load a recovery packet from a specified file
bool Load(DiskFile *diskfile, u64 offset, PACKET_HEADER &header);
public:
// Get the lenght of the packet.
u64 PacketLength(void) const;
// The the exponent of the packet.
u32 Exponent(void) const;
// The length of the recovery data
u64 BlockSize(void) const;
// The data block
DataBlock* GetDataBlock(void);
protected:
DiskFile *diskfile; // The specific file that this packet is stored in
u64 offset; // The offset at which the packet is stored
RECOVERYBLOCKPACKET packet; // The packet (excluding the actual recovery data)
MD5Context *packetcontext; // MD5 Context used to compute the packet hash
DataBlock datablock; // The recovery data block.
};
inline u64 RecoveryPacket::PacketLength(void) const
{
return packet.header.length;
}
inline u32 RecoveryPacket::Exponent(void) const
{
return packet.exponent;
}
inline u64 RecoveryPacket::BlockSize(void) const
{
return packet.header.length - sizeof(packet);
}
inline DataBlock* RecoveryPacket::GetDataBlock(void)
{
return &datablock;
}
#endif // __RECOVERYPACKET_H__
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