Source: ../../policy/backend/instruction.hh
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// -*- c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t -*-
// vim:set sts=4 ts=8:
// Copyright (c) 2001-2005 International Computer Science Institute
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software")
// to deal in the Software without restriction, subject to the conditions
// listed in the XORP LICENSE file. These conditions include: you must
// preserve this copyright notice, and you cannot mention the copyright
// holders in advertising related to the Software without their permission.
// The Software is provided WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED. This
// notice is a summary of the XORP LICENSE file; the license in that file is
// legally binding.
// $XORP: xorp/policy/backend/instruction.hh,v 1.6 2005/11/05 18:01:45 bms Exp $
#ifndef __POLICY_BACKEND_INSTRUCTION_HH__
#define __POLICY_BACKEND_INSTRUCTION_HH__
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "policy/common/element_base.hh"
#include "policy/common/operator_base.hh"
#include "policy/common/policy_exception.hh"
#include "policy/common/varrw.hh"
#include "instr_visitor.hh"
#include "instruction_base.hh"
#include <string>
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#if defined(HAVE_REGEX_H)
#include <regex.h>
#elif defined(HAVE_PCREPOSIX_H)
#include <pcre.h>
#include <pcreposix.h>
#endif
/**
* @short Push operation. Pushes a single element on the stack.
*
* The Push instruction owns the element.
*/
class Push : public Instruction {
public:
/**
* Element is owned by Push.
* Caller must not delete element.
*
* @param e element associated with push.
*/
Push(Element* e) : _elem(e) {}
~Push() { delete _elem; }
// semicolon for kdoc
INSTR_VISITABLE();
/**
* @return element associated with push.
*/
const Element& elem() const { return *_elem; }
private:
Element* _elem;
// not implemented
Push(const Push&);
Push& operator=(const Push&);
};
/**
* @short Push a set on the stack.
*
* The difference with a normal push, is that the operation does does not own
* the set element, but only contains the label of the set. The SetManager will
* match the set label with the actual element. [It is much like containing a
* pointer, and the SetManager deals with dereference].
*
* SetManager acts similar to VarRW [almost like a symbol-table].
*/
class PushSet : public Instruction {
public:
/**
* @param setid name of the set.
*/
PushSet(const string& setid) : _setid(setid) {}
INSTR_VISITABLE();
/**
* @return name of the set.
*/
const string& setid() const { return _setid; }
private:
string _setid;
};
/**
* @short Instruction that exits the current term if top of stack is false.
*
* This instruction checks if the top of the stack contains an ElemBool. If it
* is false, the current term is exited [execution continues at next term]. If
* not, normal execution continues.
*/
class OnFalseExit : public Instruction {
public:
INSTR_VISITABLE();
};
/**
* @short Instruction to read a variable via VarRW interface.
*/
class Load : public Instruction {
public:
/**
* @param var identifier of variable to load.
*/
Load(const VarRW::Id& var) : _var(var) {}
INSTR_VISITABLE();
/**
* @return identifier of variable to read.
*/
const VarRW::Id& var() const { return _var; }
private:
VarRW::Id _var;
};
/**
* @short Instruction to write a variable via VarRW interface.
*
* Argument is top most element on stack.
* 1 element popped from stack.
*/
class Store : public Instruction {
public:
/**
* @param var identifier of variable to store.
*/
Store(const VarRW::Id& var) : _var(var) {}
INSTR_VISITABLE();
/**
* @return identifier of variable to write.
*/
const VarRW::Id& var() const { return _var; }
private:
VarRW::Id _var;
};
/**
* @short Instruction to accept a route.
*/
class Accept : public Instruction {
public:
INSTR_VISITABLE();
};
/**
* @short Instruction to reject a route.
*/
class Reject : public Instruction {
public:
INSTR_VISITABLE();
};
/**
* @short An N-ary operation.
*
* Arguments are the N top-most elements of the stack.
* Top-most argument is first. Thus elements have to be pushed on stack in
* reverse order.
*
* Operation will pop N elements from the stack.
*/
class NaryInstr : public Instruction {
public:
/**
* Caller must not delete / modify operation.
*
* @param op operation of this instruction
*/
NaryInstr(Oper* op) : _op(op) {}
~NaryInstr() { delete _op; }
INSTR_VISITABLE();
/**
* @return operation associated with this instruction.
*/
const Oper& op() const { return *_op; }
private:
Oper* _op;
// not impl
NaryInstr(const NaryInstr&);
NaryInstr& operator=(const NaryInstr&);
};
#endif // __POLICY_BACKEND_INSTRUCTION_HH__
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