squawk/core/archive.cpp
2019-04-21 22:17:04 +03:00

395 lines
11 KiB
C++

/*
* <one line to give the program's name and a brief idea of what it does.>
* Copyright (C) 2019 Yury Gubich <blue@macaw.me>
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include "archive.h"
#include <sys/stat.h>
#include <sys/types.h>
#include <QStandardPaths>
#include <QDebug>
#include <QDataStream>
#include <QDir>
Core::Archive::Archive(const QString& p_jid, QObject* parent):
QObject(parent),
jid(p_jid),
opened(false),
fromTheBeginning(false),
environment(),
main(),
order()
{
}
Core::Archive::~Archive()
{
close();
}
void Core::Archive::open(const QString& account)
{
if (!opened) {
mdb_env_create(&environment);
QString path(QStandardPaths::writableLocation(QStandardPaths::CacheLocation));
path += "/" + account + "/" + jid;
QDir cache(path);
if (!cache.exists()) {
bool res = cache.mkpath(path);
if (!res) {
throw Directory(path.toStdString());
}
}
mdb_env_set_maxdbs(environment, 3);
mdb_env_open(environment, path.toStdString().c_str(), 0, 0664);
MDB_txn *txn;
mdb_txn_begin(environment, NULL, 0, &txn);
mdb_dbi_open(txn, "main", MDB_CREATE, &main);
mdb_dbi_open(txn, "order", MDB_CREATE | MDB_INTEGERKEY, &order);
mdb_dbi_open(txn, "order", MDB_CREATE, &stats);
mdb_txn_commit(txn);
fromTheBeginning = _isFromTheBeginning();
opened = true;
}
}
void Core::Archive::close()
{
if (opened) {
mdb_dbi_close(environment, stats);
mdb_dbi_close(environment, order);
mdb_dbi_close(environment, main);
mdb_env_close(environment);
opened = false;
}
}
bool Core::Archive::addElement(const Shared::Message& message)
{
if (!opened) {
throw Closed("addElement", jid.toStdString());
}
QByteArray ba;
QDataStream ds(&ba, QIODevice::WriteOnly);
message.serialize(ds);
quint64 stamp = message.getTime().toMSecsSinceEpoch();
const std::string& id = message.getId().toStdString();
MDB_val lmdbKey, lmdbData;
lmdbKey.mv_size = id.size();
lmdbKey.mv_data = (char*)id.c_str();
lmdbData.mv_size = ba.size();
lmdbData.mv_data = (uint8_t*)ba.data();
MDB_txn *txn;
mdb_txn_begin(environment, NULL, 0, &txn);
int rc;
rc = mdb_put(txn, main, &lmdbKey, &lmdbData, MDB_NOOVERWRITE);
if (rc == 0) {
MDB_val orderKey;
orderKey.mv_size = 8;
orderKey.mv_data = (uint8_t*) &stamp;
rc = mdb_put(txn, order, &orderKey, &lmdbKey, 0);
if (rc) {
qDebug() << "An element couldn't be inserted into the index" << mdb_strerror(rc);
mdb_txn_abort(txn);
return false;
} else {
rc = mdb_txn_commit(txn);
if (rc) {
qDebug() << "A transaction error: " << mdb_strerror(rc);
return false;
}
return true;
}
} else {
qDebug() << "An element couldn't been added to the archive, skipping" << mdb_strerror(rc);
mdb_txn_abort(txn);
return false;
}
}
void Core::Archive::clear()
{
if (!opened) {
throw Closed("clear", jid.toStdString());
}
MDB_txn *txn;
mdb_txn_begin(environment, NULL, 0, &txn);
mdb_drop(txn, main, 0);
mdb_drop(txn, order, 0);
mdb_txn_commit(txn);
}
Shared::Message Core::Archive::getElement(const QString& id)
{
if (!opened) {
throw Closed("getElement", jid.toStdString());
}
std::string strKey = id.toStdString();
MDB_val lmdbKey, lmdbData;
lmdbKey.mv_size = strKey.size();
lmdbKey.mv_data = (char*)strKey.c_str();
MDB_txn *txn;
int rc;
mdb_txn_begin(environment, NULL, MDB_RDONLY, &txn);
rc = mdb_get(txn, main, &lmdbKey, &lmdbData);
if (rc) {
qDebug() <<"Get error: " << mdb_strerror(rc);
mdb_txn_abort(txn);
throw NotFound(id.toStdString(), jid.toStdString());
} else {
QByteArray ba((char*)lmdbData.mv_data, lmdbData.mv_size);
QDataStream ds(&ba, QIODevice::ReadOnly);
Shared::Message msg;
msg.deserialize(ds);
mdb_txn_abort(txn);
return msg;
}
}
Shared::Message Core::Archive::newest()
{
QString id = newestId();
return getElement(id);
}
QString Core::Archive::newestId()
{
if (!opened) {
throw Closed("newestId", jid.toStdString());
}
MDB_txn *txn;
int rc;
rc = mdb_txn_begin(environment, NULL, MDB_RDONLY, &txn);
MDB_cursor* cursor;
rc = mdb_cursor_open(txn, order, &cursor);
MDB_val lmdbKey, lmdbData;
rc = mdb_cursor_get(cursor, &lmdbKey, &lmdbData, MDB_LAST);
if (rc) {
qDebug() << "Error geting newestId " << mdb_strerror(rc);
mdb_cursor_close(cursor);
mdb_txn_abort(txn);
throw new Empty(jid.toStdString());
} else {
std::string sId((char*)lmdbData.mv_data, lmdbData.mv_size);
mdb_cursor_close(cursor);
mdb_txn_abort(txn);
return sId.c_str();
}
}
Shared::Message Core::Archive::oldest()
{
return getElement(oldestId());
}
QString Core::Archive::oldestId()
{
if (!opened) {
throw Closed("oldestId", jid.toStdString());
}
MDB_txn *txn;
int rc;
rc = mdb_txn_begin(environment, NULL, MDB_RDONLY, &txn);
MDB_cursor* cursor;
rc = mdb_cursor_open(txn, order, &cursor);
MDB_val lmdbKey, lmdbData;
rc = mdb_cursor_get(cursor, &lmdbKey, &lmdbData, MDB_FIRST);
if (rc) {
qDebug() << "Error geting oldestId " << mdb_strerror(rc);
mdb_cursor_close(cursor);
mdb_txn_abort(txn);
throw new Empty(jid.toStdString());
} else {
std::string sId((char*)lmdbData.mv_data, lmdbData.mv_size);
mdb_cursor_close(cursor);
mdb_txn_abort(txn);
return sId.c_str();
}
}
long unsigned int Core::Archive::size() const
{
if (!opened) {
throw Closed("size", jid.toStdString());
}
MDB_txn *txn;
int rc;
rc = mdb_txn_begin(environment, NULL, MDB_RDONLY, &txn);
MDB_stat stat;
mdb_stat(txn, order, &stat);
mdb_txn_abort(txn);
return stat.ms_entries;
}
std::list<Shared::Message> Core::Archive::getBefore(int count, const QString& id)
{
if (!opened) {
throw Closed("getBefore", jid.toStdString());
}
std::list<Shared::Message> res;
MDB_cursor* cursor;
MDB_txn *txn;
MDB_val lmdbKey, lmdbData;
int rc;
rc = mdb_txn_begin(environment, NULL, MDB_RDONLY, &txn);
if (id == "") {
rc = mdb_cursor_open(txn, order, &cursor);
rc = mdb_cursor_get(cursor, &lmdbKey, &lmdbData, MDB_LAST);
if (rc) {
qDebug() << "Error geting before newest newest " << mdb_strerror(rc);
mdb_cursor_close(cursor);
mdb_txn_abort(txn);
throw new Empty(jid.toStdString());
} else {
std::string sId((char*)lmdbData.mv_data, lmdbData.mv_size);
}
} else {
lmdbKey.mv_size = id.size();
lmdbKey.mv_data = (char*)id.toStdString().c_str();
rc = mdb_get(txn, main, &lmdbKey, &lmdbData);
if (rc) {
qDebug() <<"Error getting before: " << mdb_strerror(rc);
mdb_txn_abort(txn);
throw NotFound(id.toStdString(), jid.toStdString());
} else {
QByteArray ba((char*)lmdbData.mv_data, lmdbData.mv_size);
QDataStream ds(&ba, QIODevice::ReadOnly);
Shared::Message msg;
msg.deserialize(ds);
quint64 stamp = msg.getTime().toMSecsSinceEpoch();
lmdbKey.mv_data = (quint8*)&stamp;
lmdbKey.mv_size = 8;
rc = mdb_cursor_open(txn, order, &cursor);
rc = mdb_cursor_get(cursor, &lmdbKey, &lmdbData, MDB_SET);
if (rc) {
qDebug() << "Error getting before " << mdb_strerror(rc);
mdb_cursor_close(cursor);
mdb_txn_abort(txn);
throw new NotFound(id.toStdString(), jid.toStdString());
} else {
rc = mdb_cursor_get(cursor, &lmdbKey, &lmdbData, MDB_PREV);
if (rc) {
qDebug() << "Error getting before " << mdb_strerror(rc);
mdb_cursor_close(cursor);
mdb_txn_abort(txn);
throw new NotFound(id.toStdString(), jid.toStdString());
}
}
}
}
do {
QByteArray ba((char*)lmdbData.mv_data, lmdbData.mv_size);
QDataStream ds(&ba, QIODevice::ReadOnly);
res.emplace_back();
Shared::Message& msg = res.back();
msg.deserialize(ds);
--count;
} while (count > 0 && mdb_cursor_get(cursor, &lmdbKey, &lmdbData, MDB_PREV) == 0);
mdb_cursor_close(cursor);
mdb_txn_abort(txn);
return res;
}
bool Core::Archive::_isFromTheBeginning()
{
std::string strKey = "beginning";
MDB_val lmdbKey, lmdbData;
lmdbKey.mv_size = strKey.size();
lmdbKey.mv_data = (char*)strKey.c_str();
MDB_txn *txn;
int rc;
mdb_txn_begin(environment, NULL, MDB_RDONLY, &txn);
rc = mdb_get(txn, stats, &lmdbKey, &lmdbData);
if (rc == MDB_NOTFOUND) {
mdb_txn_abort(txn);
return false;
} else if (rc) {
qDebug() <<"isFromTheBeginning error: " << mdb_strerror(rc);
mdb_txn_abort(txn);
throw NotFound(strKey, jid.toStdString());
} else {
uint8_t value = *(uint8_t*)(lmdbData.mv_data);
bool is;
if (value == 144) {
is = false;
} else if (value == 72) {
is = true;
} else {
qDebug() <<"isFromTheBeginning error: stored value doesn't match any magic number, the answer is most probably wrong";
}
return is;
}
}
bool Core::Archive::isFromTheBeginning()
{
if (!opened) {
throw Closed("isFromTheBeginning", jid.toStdString());
}
return fromTheBeginning;
}
bool Core::Archive::setFromTheBeginning(bool is)
{
if (!opened) {
throw Closed("setFromTheBeginning", jid.toStdString());
}
if (fromTheBeginning != is) {
fromTheBeginning = is;
const std::string& id = "beginning";
uint8_t value = 144;
if (is) {
value = 72;
}
MDB_val lmdbKey, lmdbData;
lmdbKey.mv_size = id.size();
lmdbKey.mv_data = (char*)id.c_str();
lmdbData.mv_size = sizeof value;
lmdbData.mv_data = &value;
MDB_txn *txn;
mdb_txn_begin(environment, NULL, 0, &txn);
int rc;
rc = mdb_put(txn, stats, &lmdbKey, &lmdbData, 0);
if (rc != 0) {
qDebug() << "Couldn't store beginning key into stat database:" << mdb_strerror(rc);
mdb_txn_abort(txn);
}
}
}