| // Copyright (C) 2001-2005 Open Source Telecom Corporation. |
| // Copyright (C) 2006-2010 David Sugar, Tycho Softworks. |
| // |
| // This program is free software; you can redistribute it and/or modify |
| // it under 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. |
| // |
| // This program 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 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. |
| // |
| // As a special exception to the GNU General Public License, permission is |
| // granted for additional uses of the text contained in its release |
| // of Common C++. |
| // |
| // The exception is that, if you link the Common C++ library with other |
| // files to produce an executable, this does not by itself cause the |
| // resulting executable to be covered by the GNU General Public License. |
| // Your use of that executable is in no way restricted on account of |
| // linking the Common C++ library code into it. |
| // |
| // This exception does not however invalidate any other reasons why |
| // the executable file might be covered by the GNU General Public License. |
| // |
| // This exception applies only to the code released under the |
| // name Common C++. If you copy code from other releases into a copy of |
| // Common C++, as the General Public License permits, the exception does |
| // not apply to the code that you add in this way. To avoid misleading |
| // anyone as to the status of such modified files, you must delete |
| // this exception notice from them. |
| // |
| // If you write modifications of your own for Common C++, it is your choice |
| // whether to permit this exception to apply to your modifications. |
| // If you do not wish that, delete this exception notice. |
| |
| /** |
| * @file objmap.h |
| * @short Template for creating hash indexed objects. |
| **/ |
| |
| #ifndef CCXX_OBJMAP_H |
| #define CCXX_OBJMAP_H |
| |
| #include <cc++/strchar.h> |
| |
| #ifdef CCXX_NAMESPACES |
| namespace ost { |
| #endif |
| |
| /** |
| * Used to create and manage a hash index of objects through a common |
| * type. The objects can be examined and a specific instance located |
| * by a hash key. |
| * |
| * @author David Sugar <dyfet@gnutelephony.org> |
| * @short hash indexed searchable template chain. |
| */ |
| template <class T, class K, unsigned S> |
| class objMap { |
| protected: |
| static T *objIndex[S]; |
| T* objNext; |
| const K objKey; |
| |
| virtual unsigned keyIndex(K k) |
| { |
| unsigned idx = 0; |
| unsigned char *p = (unsigned char *)&k; |
| unsigned len = sizeof(K); |
| |
| while(len--) { |
| idx ^= (idx << 1) ^ *p; |
| ++p; |
| } |
| return idx % S; |
| } |
| |
| inline unsigned getSize(void) |
| {return S;} |
| |
| objMap(const K key) |
| { |
| unsigned idx = keyIndex(key); |
| objKey = key; |
| objNext = objIndex[idx]; |
| objIndex[idx] = (T *)this; |
| } |
| public: |
| static T *getObject(keystring key); |
| }; |
| |
| template <class T, unsigned S> |
| class keyMap : public objMap<T, keystring, S> |
| { |
| keyMap(keystring key) : objMap<T, keystring, S>(key) {}; |
| |
| unsigned keyIndex(keystring k) |
| { |
| unsigned idx = 0; |
| while(*k) { |
| idx = (idx << 1) ^ (unsigned)*k; |
| ++k; |
| } |
| return idx % S; |
| } |
| }; |
| |
| template <class T, class K, unsigned S> |
| T *objMap<T, K, S>::objIndex[S](0); |
| |
| template <class T, class K, unsigned S> |
| T *objMap<T, K, S>::getObject(const keystring key) |
| { |
| T *obj = objIndex[keyIndex(key)]; |
| while(obj) { |
| if(key == obj->objKey) |
| break; |
| obj = obj->objNext; |
| } |
| return obj; |
| } |
| |
| #ifdef CCXX_NAMESPACES |
| } // namespace |
| #endif |
| |
| #endif |