Operators.h

// -*- mode: c++; c-basic-offset:4 -*-

// This file is part of libdap, A C++ implementation of the OPeNDAP Data
// Access Protocol.

// Copyright (c) 2002,2003 OPeNDAP, Inc.
// Author: James Gallagher <jgallagher@opendap.org>
//
// 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 Street, Fifth Floor, Boston, MA  02110-1301  USA
//
// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.

// (c) COPYRIGHT URI/MIT 1999
// Please read the full copyright statement in the file COPYRIGHT_URI.
//
// Authors:
//      jhrg,jimg       James Gallagher <jgallagher@gso.uri.edu>

// Templates for relational operations.
//
// jhrg 3/24/99

#ifndef _operators_h
#define _operators_h

#include "GNURegex.h"  // GNU Regex class used for string =~ op.
#include "ce_expr.tab.hh"

#pragma GCC diagnostic ignored "-Wsign-compare"

namespace libdap {

template<class T1, class T2>
bool Cmp(int op, T1 v1, T2 v2)
{
    DBGN(cerr << __PRETTY_FUNCTION__ << v1 << " " << op << " " << v2 << endl);

    switch (op) {
        case SCAN_EQUAL:
            return v1 == v2;
        case SCAN_NOT_EQUAL:
            return v1 != v2;
        case SCAN_GREATER:
            return v1 > v2;
        case SCAN_GREATER_EQL:
            return v1 >= v2;
        case SCAN_LESS:
            return v1 < v2;
        case SCAN_LESS_EQL:
            return v1 <= v2;
        case SCAN_REGEXP:
            throw Error(malformed_expr, "Regular expressions are supported for strings only.");
        default:
            throw Error(malformed_expr, "Unrecognized operator.");
    }
}

#if 0
template<class T>
static inline unsigned long long dap_floor_zero(T i)
{
    return (unsigned long long) ((i < 0) ? 0 : i);
}
#endif

#if 0
// Hack
template<class T>
static inline T dap_floor_zero(T i)
{
    return i;
}

template<class UT1, class T2>
bool USCmp(int op, UT1 v1, T2 v2)
{
    DBGN(cerr << __PRETTY_FUNCTION__ << v1 << " " << op << " " << v2 << endl);

    switch (op) {
        case SCAN_EQUAL:
            return v1 == dap_floor_zero<T2>(v2);
        case SCAN_NOT_EQUAL:
            return v1 != dap_floor_zero<T2>(v2);
        case SCAN_GREATER:
            return v1 > dap_floor_zero<T2>(v2);
        case SCAN_GREATER_EQL:
            return v1 >= dap_floor_zero<T2>(v2);
        case SCAN_LESS:
            return v1 < dap_floor_zero<T2>(v2);
        case SCAN_LESS_EQL:
            return v1 <= dap_floor_zero<T2>(v2);
        case SCAN_REGEXP:
            throw Error(malformed_expr, "Regular expressions are supported for strings only.");
        default:
            throw Error(malformed_expr, "Unrecognized operator.");
    }
}

template<class T1, class UT2>
bool SUCmp(int op, T1 v1, UT2 v2)
{
    DBGN(cerr << __PRETTY_FUNCTION__ << v1 << " " << op << " " << v2 << endl);

    switch (op) {
        case SCAN_EQUAL:
            return dap_floor_zero<T1>(v1) == v2;
        case SCAN_NOT_EQUAL:
            return dap_floor_zero<T1>(v1) != v2;
        case SCAN_GREATER:
            return dap_floor_zero<T1>(v1) > v2;
        case SCAN_GREATER_EQL:
            return dap_floor_zero<T1>(v1) >= v2;
        case SCAN_LESS:
            return dap_floor_zero<T1>(v1) < v2;
        case SCAN_LESS_EQL:
            return dap_floor_zero<T1>(v1) <= v2;
        case SCAN_REGEXP:
            throw Error(malformed_expr, "Regular expressions are supported for strings only.");
        default:
            throw Error(malformed_expr, "Unrecognized operator.");
    }
}
#endif

template<class T1, class T2>
bool StrCmp(int op, T1 v1, T2 v2)
{
    switch (op) {
        case SCAN_EQUAL:
            return v1 == v2;
        case SCAN_NOT_EQUAL:
            return v1 != v2;
        case SCAN_GREATER:
            return v1 > v2;
        case SCAN_GREATER_EQL:
            return v1 >= v2;
        case SCAN_LESS:
            return v1 < v2;
        case SCAN_LESS_EQL:
            return v1 <= v2;
        case SCAN_REGEXP: {
            Regex r(v2.c_str());
            return r.match(v1.c_str(), v1.length()) > 0;
        }
        default:
            throw Error(malformed_expr, "Unrecognized operator.");
    }
}

} // namespace libdap

#endif // _operators_h