aria2/src/IteratableChunkChecksumVali...

161 lines
4.9 KiB
C++

/* <!-- copyright */
/*
* aria2 - The high speed download utility
*
* Copyright (C) 2006 Tatsuhiro Tsujikawa
*
* This program 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.
*
* This program 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
*
* In addition, as a special exception, the copyright holders give
* permission to link the code of portions of this program with the
* OpenSSL library under certain conditions as described in each
* individual source file, and distribute linked combinations
* including the two.
* You must obey the GNU General Public License in all respects
* for all of the code used other than OpenSSL. If you modify
* file(s) with this exception, you may extend this exception to your
* version of the file(s), but you are not obligated to do so. If you
* do not wish to do so, delete this exception statement from your
* version. If you delete this exception statement from all source
* files in the program, then also delete it here.
*/
/* copyright --> */
#include "IteratableChunkChecksumValidator.h"
#include <cstring>
#include <cstdlib>
#include "util.h"
#include "message.h"
#include "DiskAdaptor.h"
#include "FileEntry.h"
#include "RecoverableException.h"
#include "DownloadContext.h"
#include "PieceStorage.h"
#include "BitfieldMan.h"
#include "LogFactory.h"
#include "Logger.h"
#include "MessageDigest.h"
#include "fmt.h"
#include "DlAbortEx.h"
namespace aria2 {
IteratableChunkChecksumValidator::IteratableChunkChecksumValidator
(const SharedHandle<DownloadContext>& dctx,
const PieceStorageHandle& pieceStorage)
: dctx_(dctx),
pieceStorage_(pieceStorage),
bitfield_(new BitfieldMan(dctx_->getPieceLength(),
dctx_->getTotalLength())),
currentIndex_(0)
{}
IteratableChunkChecksumValidator::~IteratableChunkChecksumValidator() {}
void IteratableChunkChecksumValidator::validateChunk()
{
if(!finished()) {
std::string actualChecksum;
try {
actualChecksum = calculateActualChecksum();
if(actualChecksum == dctx_->getPieceHashes()[currentIndex_]) {
bitfield_->setBit(currentIndex_);
} else {
A2_LOG_INFO
(fmt(EX_INVALID_CHUNK_CHECKSUM,
static_cast<unsigned long>(currentIndex_),
util::itos(getCurrentOffset(), true).c_str(),
util::toHex(dctx_->getPieceHashes()[currentIndex_]).c_str(),
util::toHex(actualChecksum).c_str()));
bitfield_->unsetBit(currentIndex_);
}
} catch(RecoverableException& ex) {
A2_LOG_DEBUG_EX(fmt("Caught exception while validating piece index=%lu."
" Some part of file may be missing."
" Continue operation.",
static_cast<unsigned long>(currentIndex_)),
ex);
bitfield_->unsetBit(currentIndex_);
}
++currentIndex_;
if(finished()) {
pieceStorage_->setBitfield(bitfield_->getBitfield(), bitfield_->getBitfieldLength());
}
}
}
std::string IteratableChunkChecksumValidator::calculateActualChecksum()
{
off_t offset = getCurrentOffset();
size_t length;
// When validating last piece
if(currentIndex_+1 == dctx_->getNumPieces()) {
length = dctx_->getTotalLength()-offset;
} else {
length = dctx_->getPieceLength();
}
return digest(offset, length);
}
void IteratableChunkChecksumValidator::init()
{
ctx_ = MessageDigest::create(dctx_->getPieceHashType());
bitfield_->clearAllBit();
currentIndex_ = 0;
}
std::string IteratableChunkChecksumValidator::digest(off_t offset, size_t length)
{
unsigned char buf[4096];
ctx_->reset();
off_t max = offset+length;
while(offset < max) {
size_t r = pieceStorage_->getDiskAdaptor()->readData
(buf, std::min(static_cast<off_t>(sizeof(buf)), max-offset), offset);
if(r == 0) {
throw DL_ABORT_EX
(fmt(EX_FILE_READ, dctx_->getBasePath().c_str(),
"data is too short"));
}
ctx_->update(buf, r);
offset += r;
}
return ctx_->digest();
}
bool IteratableChunkChecksumValidator::finished() const
{
if(currentIndex_ >= dctx_->getNumPieces()) {
return true;
} else {
return false;
}
}
off_t IteratableChunkChecksumValidator::getCurrentOffset() const
{
return (off_t)currentIndex_*dctx_->getPieceLength();
}
uint64_t IteratableChunkChecksumValidator::getTotalLength() const
{
return dctx_->getTotalLength();
}
} // namespace aria2