Aegisub/aegisub/libaegisub/common/mru.cpp
Thomas Goyne ef3414931f Fix off-by-one error in MRU::GetEntry
Originally committed to SVN as r6009.
2011-12-22 21:11:01 +00:00

115 lines
3.1 KiB
C++

// Copyright (c) 2010, Amar Takhar <verm@aegisub.org>
//
// Permission to use, copy, modify, and distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
//
// $Id$
/// @file mru.cpp
/// @brief Most Recently Used (MRU) Lists
/// @ingroup libaegisub
#include "libaegisub/cajun/writer.h"
#include "libaegisub/access.h"
#include "libaegisub/io.h"
#include "libaegisub/json.h"
#include "libaegisub/log.h"
#include "libaegisub/mru.h"
namespace agi {
MRUManager::MRUManager(const std::string &config, const std::string &default_config): config_name(config) {
LOG_D("agi/mru") << "Loading MRU List";
json::Object root(json_util::file(config, default_config));
for (json::Object::const_iterator it(root.begin()); it != root.end(); ++it)
Load(it->first, it->second);
}
MRUManager::~MRUManager() {
}
MRUManager::MRUListMap &MRUManager::Find(std::string const& key) {
MRUMap::iterator index = mru.find(key);
if (index == mru.end())
throw MRUErrorInvalidKey("Invalid key value");
return index->second;
}
void MRUManager::Add(const std::string &key, const std::string &entry) {
MRUListMap &map = Find(key);
map.remove(entry);
map.push_front(entry);
Prune(map);
Flush();
}
void MRUManager::Remove(const std::string &key, const std::string &entry) {
Find(key).remove(entry);
Flush();
}
const MRUManager::MRUListMap* MRUManager::Get(const std::string &key) {
return &Find(key);
}
std::string const& MRUManager::GetEntry(const std::string &key, size_t entry) {
const MRUManager::MRUListMap *map = Get(key);
if (entry >= map->size())
throw MRUErrorIndexOutOfRange("Requested element index is out of range.");
MRUListMap::const_iterator index = map->begin();
advance(index, entry);
return *index;
}
void MRUManager::Flush() {
json::Object out;
for (MRUMap::const_iterator i = mru.begin(); i != mru.end(); ++i) {
json::Array &array = out[i->first];
copy(i->second.begin(), i->second.end(), std::back_inserter(array));
}
json::Writer::Write(out, io::Save(config_name).Get());
}
/// @brief Prune MRUListMap to the desired length.
/// This uses the user-set values for MRU list length.
inline void MRUManager::Prune(MRUListMap& map) {
map.resize(std::min<size_t>(16, map.size()));
}
/// @brief Load MRU Lists.
/// @param key List name.
/// @param array json::Array of values.
void MRUManager::Load(const std::string &key, const json::Array& array) {
try {
copy(array.begin(), array.end(), back_inserter(mru[key]));
}
catch (json::Exception const&) {
// Out of date MRU file; just discard the data and skip it
}
Prune(mru[key]);
}
}