tripwire-open-source/src/fco/fconametbl.h

185 lines
7.1 KiB
C++

//
// The developer of the original code and/or files is Tripwire, Inc.
// Portions created by Tripwire, Inc. are copyright (C) 2000 Tripwire,
// Inc. Tripwire is a registered trademark of Tripwire, Inc. All rights
// reserved.
//
// This program is free software. The contents of this file are subject
// to the terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2 of the License, or (at your
// option) any later version. You may redistribute it and/or modify it
// only in compliance with the GNU General Public License.
//
// This program is distributed in the hope that it will be useful.
// However, this program is distributed AS-IS WITHOUT ANY
// WARRANTY; INCLUDING THE IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS
// FOR A PARTICULAR PURPOSE. Please see the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
//
// Nothing in the GNU General Public License or any other license to use
// the code or files shall permit you to use Tripwire's trademarks,
// service marks, or other intellectual property without Tripwire's
// prior written consent.
//
// If you have any questions, please contact Tripwire, Inc. at either
// info@tripwire.org or www.tripwire.org.
//
///////////////////////////////////////////////////////////////////////////////
// fconametbl.h
//
// cFCONameTbl -- a hash table used in the implementation of cFCOName
#ifndef __FCONAMETBL_H
#define __FCONAMETBL_H
#ifndef __DEBUG_H
#include "core/debug.h"
#endif
#ifndef __REFCOUNTOBJ_H
#include "core/refcountobj.h"
#endif
#ifndef __HASHTABLE_H
#include "core/hashtable.h"
#endif
// uncomment this to allocate fconametblnodes from a pool.
/*
#ifndef __OBJECTPOOL_H
#include "objectpool.h"
#endif
*/
// end TODO
class cFCONameTbl_i;
///////////////////////////////////////////////////////////////////////////////
// cFCONameTblNode -- a node in the cFCONameTbl, this class has the following
// properties:
// (1) it is reference counted, so ambiguity over who owns it doesn't exist
// (2) it keeps track of a case-sensitive character string
// (3) it keeps a pointer to another cFCONameTblNode that is the lower-case
// version of the node (if the node is totally lower case, then mpLowerNode
// is NULL, but GetLowercaseNode() still returns a valid pointer)
// TODO -- make this serializable
///////////////////////////////////////////////////////////////////////////////
class cFCONameTblNode : public cRefCountObj
{
friend class cFCONameTbl;
public:
bool operator== (const cFCONameTblNode& rhs) const;
bool operator!= (const cFCONameTblNode& rhs) const;
// for efficency, op== is defined as (this == &rhs)
const cFCONameTblNode* GetLowercaseNode() const;
void SetLowercaseNode(cFCONameTblNode* pNewNode);
// gets and sets the lowercase node pointer. Might point to itself if the string
// this node contains is totally lower case.
TCHAR* GetString() const;
// gets the string associated with this node
void SetString(const TSTRING& newStr);
// sets the string associated with this node
// TODO -- this is a very dangerous operation to do; do we ever want the client
// to be able to do this (that is, should this method exist)?
// uncomment to allocate these from a pool
// static cObjectPoolBase msAllocator;
// void* operator new(size_t) { return msAllocator.Alloc(); }
// void operator delete(void* addr) { msAllocator.Free(addr); }
protected:
// these are protected to keep the client from creating nodes on the stack
// or delete()ing them.
cFCONameTblNode(const TSTRING& name, const cFCONameTblNode* node);
~cFCONameTblNode();
virtual void Delete() const;
// overridden from cRefCountObj; this is done so that if we are alloced
// from a memory pool, we can be deleted appropriately.
private:
cFCONameTblNode(const cFCONameTblNode& rhs); // not impl
cFCONameTblNode& operator= (const cFCONameTblNode& rhs);// not impl
TCHAR* mpString;
const cFCONameTblNode* mpLowerNode;
};
///////////////////////////////////////////////////////////////////////////////
// cFCONameTbl -- keeps a hash table of cFCONameTblNodes. This class does the following:
// (1) serves as a factory for cFCONameTableNodes, returning objects that have
// properly filled out mpLowerNode fields
// (2) Keeps track of all nodes created; two successive calls to create "aBc" will
// return the same pointer; a call to create "abc" will return a pointer to the
// Node("aBc")->GetLowercaseNode()
///////////////////////////////////////////////////////////////////////////////
class cFCONameTbl
{
public:
cFCONameTbl(int defSize = HASH_VERY_LARGE);
// defSize is the initial hash table size
~cFCONameTbl();
cFCONameTblNode* CreateNode(const TSTRING& nodeName);
// if the named node already exists in the table, it returns a pointer to the
// existing node; otherwise, it creates the node and its lower case representation,
// (if the lowercase node doesn't already exist),adds them to the table
// and returns a pointer to them. The returned object has been AddRef()ed
void Clear();
// clears out all the entries in the table
///////////////////////////////////////////////////////////////////////////////
// cCharCmp -- class used with the hash table that does a string compare
// of two TCHAR*s to determine equality
class cCharCmp
{
public:
bool operator()(const TCHAR* lhs, const TCHAR* rhs)
{
return (_tcscmp(lhs,rhs) == 0);
}
};
private:
// TODO -- it is not evident what type the KEY_TYPE should be for the hash tbl; if it is
// a string, we will be storing two copies of all the strings! If it is a const TCHAR*, then
// the equality operator won't work (maybe we should template the hash table with the operators
// needed for the hash as well)
cHashTable<const TCHAR*, cFCONameTblNode*, cCharCmp> mTable;
};
//#############################################################################
// inline implementation
//#############################################################################
////////////////////////
// cFCONameTblNode
////////////////////////
inline bool cFCONameTblNode::operator== (const cFCONameTblNode& rhs) const
{
return (this == &rhs);
}
inline bool cFCONameTblNode::operator!= (const cFCONameTblNode& rhs) const
{
return (this != &rhs);
}
inline const cFCONameTblNode* cFCONameTblNode::GetLowercaseNode() const
{
// if mpLowerNode == NULL, then we assume that we are the lowercase node.
if(! mpLowerNode)
return this;
return mpLowerNode;
}
inline TCHAR* cFCONameTblNode::GetString() const
{
return mpString;
}
#endif