mapnik/plugins/input/postgis/resultset.hpp
2024-07-22 10:20:47 +01:00

121 lines
3.4 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2024 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
*
*****************************************************************************/
#ifndef POSTGIS_RESULTSET_HPP
#define POSTGIS_RESULTSET_HPP
extern "C" {
#include "libpq-fe.h"
}
class IResultSet
{
public:
// virtual IResultSet& operator=(const IResultSet& rhs) = 0;
virtual ~IResultSet() {}
virtual void close() = 0;
virtual int getNumFields() const = 0;
virtual bool next() = 0;
virtual const char* getFieldName(int index) const = 0;
virtual int getFieldLength(int index) const = 0;
virtual int getFieldLength(const char* name) const = 0;
virtual int getTypeOID(int index) const = 0;
virtual int getTypeOID(const char* name) const = 0;
virtual bool isNull(int index) const = 0;
virtual const char* getValue(int index) const = 0;
virtual const char* getValue(const char* name) const = 0;
};
class ResultSet : public IResultSet,
private mapnik::util::noncopyable
{
public:
ResultSet(PGresult* res)
: res_(res)
, pos_(-1)
{
numTuples_ = PQntuples(res_);
}
virtual void close()
{
PQclear(res_);
res_ = 0;
}
virtual ~ResultSet() { PQclear(res_); }
virtual int getNumFields() const { return PQnfields(res_); }
int pos() const { return pos_; }
int size() const { return numTuples_; }
virtual bool next() { return (++pos_ < numTuples_); }
virtual const char* getFieldName(int index) const { return PQfname(res_, index); }
virtual int getFieldLength(int index) const { return PQgetlength(res_, pos_, index); }
virtual int getFieldLength(const char* name) const
{
int col = PQfnumber(res_, name);
if (col >= 0)
{
return PQgetlength(res_, pos_, col);
}
return 0;
}
virtual int getTypeOID(int index) const { return PQftype(res_, index); }
virtual int getTypeOID(const char* name) const
{
int col = PQfnumber(res_, name);
if (col >= 0)
{
return PQftype(res_, col);
}
return 0;
}
virtual bool isNull(int index) const { return static_cast<bool>(PQgetisnull(res_, pos_, index)); }
virtual const char* getValue(int index) const { return PQgetvalue(res_, pos_, index); }
virtual const char* getValue(const char* name) const
{
int col = PQfnumber(res_, name);
if (col >= 0)
{
return getValue(col);
}
return 0;
}
private:
PGresult* res_;
int pos_;
int numTuples_;
};
#endif // POSTGIS_RESULTSET_HPP