mirror of
https://github.com/nzbget/nzbget.git
synced 2026-01-10 06:57:44 -05:00
134 lines
4.1 KiB
C++
134 lines
4.1 KiB
C++
// 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
|
|
|
|
#include "nzbget.h"
|
|
#include "par2cmdline.h"
|
|
|
|
#ifdef _MSC_VER
|
|
#ifdef _DEBUG
|
|
#undef THIS_FILE
|
|
static char THIS_FILE[]=__FILE__;
|
|
#define new DEBUG_NEW
|
|
#endif
|
|
#endif
|
|
|
|
namespace Par2
|
|
{
|
|
|
|
RecoveryPacket::RecoveryPacket(void)
|
|
{
|
|
diskfile = NULL;
|
|
offset = 0;
|
|
packetcontext = NULL;
|
|
}
|
|
|
|
RecoveryPacket::~RecoveryPacket(void)
|
|
{
|
|
delete packetcontext;
|
|
}
|
|
|
|
// Create a recovery packet.
|
|
|
|
// The packet header can be almost completely filled in using the supplied
|
|
// information and computation of the hash of the packet started immediately.
|
|
// The hash will be updated as new data is written to the packet.
|
|
|
|
void RecoveryPacket::Create(DiskFile *_diskfile,
|
|
u64 _offset,
|
|
u64 _blocksize,
|
|
u32 _exponent,
|
|
const MD5Hash &_setid)
|
|
{
|
|
diskfile = _diskfile;
|
|
offset = _offset;
|
|
|
|
// Record everything we know in the packet.
|
|
packet.header.magic = packet_magic;
|
|
packet.header.length = sizeof(packet) + _blocksize;
|
|
//packet.header.hash; // Not known yet.
|
|
packet.header.setid = _setid;
|
|
packet.header.type = recoveryblockpacket_type;
|
|
packet.exponent = _exponent;
|
|
|
|
// Start computation of the packet hash
|
|
packetcontext = new MD5Context;
|
|
packetcontext->Update(&packet.header.setid,
|
|
sizeof(RECOVERYBLOCKPACKET)-offsetof(RECOVERYBLOCKPACKET, header.setid));
|
|
|
|
// Set the data block to immediatly follow the header on disk
|
|
datablock.SetLocation(_diskfile, _offset + sizeof(packet));
|
|
datablock.SetLength(_blocksize);
|
|
}
|
|
|
|
// Write data from the buffer to the data block on disk
|
|
bool RecoveryPacket::WriteData(u64 position,
|
|
size_t size,
|
|
const void *buffer)
|
|
{
|
|
// Update the packet hash
|
|
packetcontext->Update(buffer, size);
|
|
|
|
// Write the data to the data block
|
|
size_t wrote;
|
|
return datablock.WriteData(position, size, buffer, wrote);
|
|
}
|
|
|
|
// Write the header of the packet to disk
|
|
bool RecoveryPacket::WriteHeader(void)
|
|
{
|
|
// Finish computing the packet hash
|
|
packetcontext->Final(packet.header.hash);
|
|
|
|
// Write the header to disk
|
|
return diskfile->Write(offset, &packet, sizeof(packet));
|
|
}
|
|
|
|
// Load the recovery packet from disk.
|
|
//
|
|
// The header of the packet will already have been read from disk. The only
|
|
// thing that actually needs to be read is the exponent value.
|
|
// The recovery data is not read from disk at this point. Its location
|
|
// is recovered in the DataBlock object.
|
|
|
|
bool RecoveryPacket::Load(DiskFile *_diskfile,
|
|
u64 _offset,
|
|
PACKET_HEADER &_header)
|
|
{
|
|
diskfile = _diskfile;
|
|
offset = _offset;
|
|
|
|
// Is the packet actually large enough
|
|
if (_header.length <= sizeof(packet))
|
|
{
|
|
return false;
|
|
}
|
|
|
|
// Save the fixed header
|
|
packet.header = _header;
|
|
|
|
// Set the data block to immediatly follow the header on disk
|
|
datablock.SetLocation(diskfile, offset + sizeof(packet));
|
|
datablock.SetLength(packet.header.length - sizeof(packet));
|
|
|
|
// Read the rest of the packet header
|
|
return diskfile->Read(offset + sizeof(packet.header), &packet.exponent, sizeof(packet)-sizeof(packet.header));
|
|
}
|
|
|
|
} // end namespace Par2
|