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/*
* The Mana World Server
* Copyright 2004 The Mana World Development Team
*
* This file is part of The Mana World.
*
* The Mana World 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 any later version.
*
* The Mana World 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 The Mana World; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id$
*/
#include "dalexcept.h"
#include "mysqldataprovider.h"
namespace tmwserv
{
namespace dal
{
/**
* Constructor.
*/
MySqlDataProvider::MySqlDataProvider(void)
throw()
: mDb(0)
{
// NOOP
}
/**
* Destructor.
*/
MySqlDataProvider::~MySqlDataProvider(void)
throw()
{
// we are using the MySQL C API, there are no exceptions to catch.
// make sure that the database is closed.
// disconnect() calls mysql_close() which takes care of freeing
// the memory allocated for the handle.
if (mIsConnected) {
disconnect();
}
}
/**
* Get the database backend name.
*/
DbBackends
MySqlDataProvider::getDbBackend(void) const
throw()
{
return DB_BKEND_MYSQL;
}
/**
* Create a connection to the database.
*/
void
MySqlDataProvider::connect(const std::string& dbName,
const std::string& userName,
const std::string& password)
{
if (mIsConnected) {
return;
}
// allocate and initialize a new MySQL object suitable
// for mysql_real_connect().
mDb = mysql_init(NULL);
if (!mDb) {
throw DbConnectionFailure(
"unable to initialize the MySQL library: no memory");
}
// insert connection options here.
// actually establish the connection.
if (!mysql_real_connect(mDb, // handle to the connection
NULL, // localhost
userName.c_str(), // user name
password.c_str(), // user password
dbName.c_str(), // database name
0, // use default TCP port
NULL, // use defaut socket
0)) // client flags
{
std::string msg(mysql_error(mDb));
mysql_close(mDb);
throw DbConnectionFailure(msg);
}
mIsConnected = true;
}
/**
* Execute a SQL query.
*/
const RecordSet&
MySqlDataProvider::execSql(const std::string& sql,
const bool refresh)
{
if (!mIsConnected) {
throw std::runtime_error("not connected to database");
}
// do something only if the query is different from the previous
// or if the cache must be refreshed
// otherwise just return the recordset from cache.
if (refresh || (sql != mSql)) {
mRecordSet.clear();
// actually execute the query.
if (mysql_query(mDb, sql.c_str()) != 0) {
throw DbSqlQueryExecFailure(mysql_error(mDb));
}
if (mysql_field_count(mDb) > 0) {
MYSQL_RES* res;
// get the result of the query.
if (!(res = mysql_store_result(mDb))) {
throw DbSqlQueryExecFailure(mysql_error(mDb));
}
// set the field names.
unsigned int nFields = mysql_num_fields(res);
MYSQL_FIELD* fields = mysql_fetch_fields(res);
Row fieldNames;
for (unsigned int i = 0; i < nFields; ++i) {
fieldNames.push_back(fields[i].name);
}
mRecordSet.setColumnHeaders(fieldNames);
// populate the RecordSet.
MYSQL_ROW row;
while ((row = mysql_fetch_row(res))) {
Row r;
for (unsigned int i = 0; i < nFields; ++i) {
r.push_back(static_cast<char *>(row[i]));
}
mRecordSet.add(r);
}
// free memory
mysql_free_result(res);
}
}
return mRecordSet;
}
/**
* Close the connection to the database.
*/
void
MySqlDataProvider::disconnect(void)
{
if (!mIsConnected) {
return;
}
// mysql_close() closes the connection and deallocates the connection
// handle allocated by mysql_init().
mysql_close(mDb);
// deinitialize the MySQL client library.
mysql_library_end();
mDb = 0;
mIsConnected = false;
}
} // namespace dal
} // namespace tmwserv
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