aria2/src/WrDiskCache.cc

130 lines
3.9 KiB
C++

/* <!-- copyright */
/*
* aria2 - The high speed download utility
*
* Copyright (C) 2012 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 "WrDiskCache.h"
#include <cassert>
#include "WrDiskCacheEntry.h"
#include "LogFactory.h"
#include "fmt.h"
namespace aria2 {
WrDiskCache::WrDiskCache(size_t limit) : limit_(limit), total_(0), clock_(0) {}
WrDiskCache::~WrDiskCache()
{
if (total_) {
A2_LOG_WARN(fmt("Write disk cache is not empty size=%lu",
static_cast<unsigned long>(total_)));
}
}
bool WrDiskCache::add(WrDiskCacheEntry* ent)
{
ent->setSizeKey(ent->getSize());
ent->setLastUpdate(++clock_);
std::pair<EntrySet::iterator, bool> rv = set_.insert(ent);
if (rv.second) {
total_ += ent->getSize();
ensureLimit();
return true;
}
else {
A2_LOG_WARN(fmt("Found duplicate cache entry a.{size=%lu,clock=%" PRId64
"} b{size=%lu,clock=%" PRId64 "}",
static_cast<unsigned long>((*rv.first)->getSize()),
(*rv.first)->getLastUpdate(),
static_cast<unsigned long>(ent->getSize()),
ent->getLastUpdate()));
return false;
}
}
bool WrDiskCache::remove(WrDiskCacheEntry* ent)
{
if (set_.erase(ent)) {
A2_LOG_DEBUG(fmt("Removed cache entry size=%lu, clock=%" PRId64,
static_cast<unsigned long>(ent->getSize()),
ent->getLastUpdate()));
total_ -= ent->getSize();
return true;
}
else {
return false;
}
}
bool WrDiskCache::update(WrDiskCacheEntry* ent, ssize_t delta)
{
if (!set_.erase(ent)) {
return false;
}
A2_LOG_DEBUG(fmt("Update cache entry size=%lu, delta=%ld, clock=%" PRId64,
static_cast<unsigned long>(ent->getSize()),
static_cast<long>(delta), ent->getLastUpdate()));
ent->setSizeKey(ent->getSize());
ent->setLastUpdate(++clock_);
set_.insert(ent);
if (delta < 0) {
assert(total_ >= static_cast<size_t>(-delta));
}
total_ += delta;
ensureLimit();
return true;
}
void WrDiskCache::ensureLimit()
{
while (total_ > limit_) {
auto i = set_.begin();
WrDiskCacheEntry* ent = *i;
A2_LOG_DEBUG(fmt("Force flush cache entry size=%lu, clock=%" PRId64,
static_cast<unsigned long>(ent->getSizeKey()),
ent->getLastUpdate()));
total_ -= ent->getSize();
ent->writeToDisk();
set_.erase(i);
ent->setSizeKey(ent->getSize());
ent->setLastUpdate(++clock_);
set_.insert(ent);
}
}
} // namespace aria2