literals.h

/***************************************************************
 *
 * Copyright (C) 1990-2007, Condor Team, Computer Sciences Department,
 * University of Wisconsin-Madison, WI.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you
 * may not use this file except in compliance with the License.  You may
 * obtain a copy of the License at
 * 
 *    http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 ***************************************************************/


#ifndef __CLASSAD_LITERALS_H__
#define __CLASSAD_LITERALS_H__

#include <vector>

BEGIN_NAMESPACE( classad )

typedef std::vector<ExprTree*> ArgumentList;

class Literal : public ExprTree 
{
    public:
        virtual ~Literal ();

        Literal(const Literal &literal);

        Literal &operator=(const Literal &literal);

        static Literal* MakeAbsTime( abstime_t *now=NULL );

        /* Creates an absolute time literal, from the string timestr, 
         *parsing it as the regular expression:
         D* dddd [D* dd [D* dd [D* dd [D* dd [D* dd D*]]]]] [-dddd | +dddd | z | Z]
         D => non-digit, d=> digit
         Ex - 2003-01-25T09:00:00-0600
        */
        static Literal* MakeAbsTime( std::string timestr);

        static Literal* MakeRelTime( time_t secs=-1 );

        static Literal* MakeRelTime( time_t t1, time_t t2 );

        /* Creates a relative time literal, from the string timestr, 
         *parsing it as [[[days+]hh:]mm:]ss
         * Ex - 1+00:02:00
        */      
        static Literal* MakeRelTime(std::string str);

        static Literal* MakeReal(std::string realstr);

        virtual ExprTree* Copy( ) const;

        void CopyFrom(const Literal &literal);

        static Literal*MakeLiteral( const Value& v, Value::NumberFactor f=
                    Value::NO_FACTOR );

        void GetComponents( Value& v, Value::NumberFactor &f ) const;

        void GetValue( Value& v ) const;
        
        /* Takes the number of seconds since the epoch as argument - epochsecs, 
         *and returns the timezone offset(relative to GMT) in the currect locality
         */
        static int findOffset(time_t epochsecs);

        virtual bool SameAs(const ExprTree *tree) const;

        friend bool operator==(Literal &literal1, Literal &literal2);

    protected:
        Literal ();

    private:
        friend class FunctionCall;
        friend class ClassAd;
        friend class ExprList;
        friend class Operation;

        virtual void _SetParentScope( const ClassAd* ){ }
        virtual bool _Flatten( EvalState&, Value&, ExprTree*&, int* ) const;
        virtual bool _Evaluate (EvalState &, Value &) const;
        virtual bool _Evaluate (EvalState &, Value &, ExprTree *&) const;

        // literal specific information
        Value               value;
        Value::NumberFactor factor;
};

END_NAMESPACE // classad

#endif//__CLASSAD_LITERALS_H__