Source: ../../policy/backend/iv_exec.hh
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// 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/iv_exec.hh,v 1.2 2005/03/25 02:54:12 pavlin Exp $
#ifndef __POLICY_BACKEND_IV_EXEC_HH__
#define __POLICY_BACKEND_IV_EXEC_HH__
#include "policy/common/dispatcher.hh"
#include "policy/common/varrw.hh"
#include "policy/common/policy_exception.hh"
#include "instruction.hh"
#include "set_manager.hh"
#include "regex.h"
#include "term_instr.hh"
#include "policy_instr.hh"
#include <stack>
/**
* @short Visitor that executes instructions
*
* The execution process may be optimized by not using visitors. Having
* instructions implement a method that returns a flow action directly.
*/
class IvExec : public InstrVisitor {
public:
/**
* A FlowAction is what has to be done with the route. DEFAULT is the
* default action which is normally "go to the next term", or if the last
* term, ACCEPT.
*/
enum FlowAction {
ACCEPT,
REJ,
DEFAULT
};
/**
* @short Run time errors, such as doing unsupported operations.
*
* The semantic check should get rid of these.
*/
class RuntimeError : public PolicyException {
public:
RuntimeError(const string& err) : PolicyException(err) {}
};
/**
* Execute the give policies with the given varrw [i.e. route].
*
* @param policies policies to execute.
* @param sman set manager to use for loading sets.
* @param varrw interface to read/write route variables.
* @param os if not null, an execution trace will be output to stream.
*/
IvExec(vector<PolicyInstr*>& policies, SetManager& sman,
VarRW& varrw,
ostream* os);
~IvExec();
/**
* Execute the policies.
*/
FlowAction run();
/**
* Execute a policy.
*
* @param pi policy to execute
*/
FlowAction runPolicy(PolicyInstr& pi);
/**
* Execute a term.
*
* @param ti term to execute.
*/
FlowAction runTerm(TermInstr& ti);
/**
* @param p push to execute.
*/
void visit(Push& p);
/**
* @param ps push of a set to execute.
*/
void visit(PushSet& ps);
/**
* @param x OnFalseExit to execute.
*/
void visit(OnFalseExit& x);
/**
* @param re Regex to execute.
*/
void visit(Regex& re);
/**
* @param l Load to execute.
*/
void visit(Load& l);
/**
* @param s Store to execute.
*/
void visit(Store& s);
/**
* @param a accept the route.
*/
void visit(Accept& a);
/**
* @param r reject the route.
*/
void visit(Reject& r);
/**
* @param nary N-ary instruction to execute.
*/
void visit(NaryInstr& nary);
/**
* @return String representation of flow action.
* @param fa Flow action to convert.
*/
static string fa2str(const FlowAction& fa);
private:
/**
* Do garbage collection.
*/
void clear_trash();
vector<PolicyInstr*>& _policies;
stack<const Element*> _stack;
SetManager& _sman;
VarRW& _varrw;
bool _finished;
Dispatcher _disp;
FlowAction _fa;
set<Element*> _trash;
ostream* _os;
// not impelmented
IvExec(const IvExec&);
IvExec& operator=(const IvExec&);
};
#endif // __POLICY_BACKEND_IV_EXEC_HH__
Generated by: pavlin on possum.icir.org on Wed Apr 13 21:53:13 2005, using kdoc $.