mapnik/plugins/input/postgis/connection.hpp
2011-05-10 14:22:47 +00:00

146 lines
4 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2006 Artem Pavlenko
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*****************************************************************************/
//$Id: connection.hpp 17 2005-03-08 23:58:43Z pavlenko $
#ifndef CONNECTION_HPP
#define CONNECTION_HPP
#include <mapnik/datasource.hpp>
extern "C"
{
#include "libpq-fe.h"
}
#include "resultset.hpp"
class Connection
{
private:
PGconn *conn_;
int cursorId;
bool closed_;
public:
Connection(std::string const& connection_str)
:cursorId(0),
closed_(false)
{
conn_=PQconnectdb(connection_str.c_str());
if (PQstatus(conn_) != CONNECTION_OK)
{
std::ostringstream s("Postgis Plugin: PSQL error");
if (conn_ )
{
std::string msg = PQerrorMessage( conn_ );
if ( ! msg.empty() )
{
s << ":\n" << msg.substr( 0, msg.size() - 1 );
}
}
throw mapnik::datasource_exception( s.str() );
}
}
bool execute(const std::string& sql) const
{
PGresult *result=PQexec(conn_,sql.c_str());
bool ok=(result && PQresultStatus(result)==PGRES_COMMAND_OK);
PQclear(result);
return ok;
}
boost::shared_ptr<ResultSet> executeQuery(const std::string& sql,int type=0) const
{
PGresult *result=0;
if (type==1)
{
result=PQexecParams(conn_,sql.c_str(),0,0,0,0,0,1);
}
else
{
result=PQexec(conn_,sql.c_str());
}
if(!result || PQresultStatus(result) != PGRES_TUPLES_OK)
{
std::ostringstream s("Postgis Plugin: PSQL error");
if (conn_ )
{
std::string msg = PQerrorMessage( conn_ );
if ( ! msg.empty() )
{
s << ":\n" << msg.substr( 0, msg.size() - 1 );
}
s << "\nFull sql was: '" << sql << "'\n";
}
if (result)
PQclear(result);
throw mapnik::datasource_exception( s.str() );
}
return boost::shared_ptr<ResultSet>(new ResultSet(result));
}
std::string client_encoding() const
{
return PQparameterStatus(conn_,"client_encoding");
}
bool isOK() const
{
return (PQstatus(conn_)!=CONNECTION_BAD);
}
void close()
{
if (!closed_)
{
PQfinish(conn_);
#ifdef MAPNIK_DEBUG
std::clog << "PostGIS: datasource closed, also closing connection - " << conn_ << std::endl;
#endif
closed_ = true;
}
}
std::string new_cursor_name()
{
std::ostringstream s;
s << "mapnik_" << (cursorId++);
return s.str();
}
~Connection()
{
if (!closed_)
{
PQfinish(conn_);
#ifdef MAPNIK_DEBUG
std::clog << "PostGIS: postgresql connection closed - " << conn_ << std::endl;
#endif
closed_ = true;
}
}
};
#endif //CONNECTION_HPP