http://www.ousob.com --- Legacy Redefined OuSob - File: /wwwroot/clipx/usr/include/wvstreams/xplc/utils.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- * * XPLC - Cross-Platform Lightweight Components * Copyright (C) 2000-2003, Pierre Phaneuf * Copyright (C) 2001, Stéphane Lajoie * Copyright (C) 2002-2004, Net Integration Technologies, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License * as published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 * USA * * As a special exception, you may use this file as part of a free * software library without restriction. Specifically, if other files * instantiate templates or use macros or inline functions from this * file, or you compile this file and link it with other files to * produce an executable, this file does not by itself cause the * resulting executable to be covered by the GNU Lesser General Public * License. This exception does not however invalidate any other * reasons why the executable file might be covered by the GNU Lesser * General Public License. */ #ifndef __XPLC_UTILS_H__ #define __XPLC_UTILS_H__ #if defined(__GNUC__) && __GNUC__ > 3 # pragma GCC system_header #endif /** \file * * Various utility functions, macros and templates. */ #include <stddef.h> #include <xplc/core.h> #include <xplc/IWeakRef.h> /** * Utility structure used for the interface map. */ struct UUID_Info { //@{ const UUID* iid; ptrdiff_t delta; //@} }; /** * Start the interface map for "component". */ #define UUID_MAP_BEGIN(component) const UUID_Info component::xplc_iobject_uuids[] = { /** * Add an entry to an interface map. */ #define UUID_MAP_ENTRY(iface) { &iface##_IID, reinterpret_cast<ptrdiff_t>(static_cast<iface*>(reinterpret_cast<ThisXPLCComponent*>(1))) - 1 }, /** * Add an entry to an interface map for an ambiguous interface. The * second parameter is the interface that should be used to * disambiguate. */ #define UUID_MAP_ENTRY_2(iface, iface2) { &iface##_IID, reinterpret_cast<ptrdiff_t>(static_cast<iface2*>(reinterpret_cast<ThisXPLCComponent*>(1))) - 1 }, /** * Marks the end of an interface map. */ #define UUID_MAP_END { 0, 0 } }; class WeakRef; /** * Helper internal structure. Used for implementing IMPLEMENT_IOBJECT. */ struct IObjectImplInternal { /** * Holds the reference count. */ unsigned int refcount; /** * Pointer to a weak reference object. This object is lazily * instantiated, so the pointer is NULL until a weak reference is * needed. */ WeakRef* weakref; IObjectImplInternal(): refcount(1), weakref(0) { } /** * Used to implement IObject::getInterface(). */ IObject* getInterface(void* self, const UUID& uuid, const UUID_Info* uuidlist); }; #ifndef xplcdelete /** * Internal macro. This macro is needed to cooperate correctly with * the "delete detector". */ #define xplcdelete delete #endif /** * Helper macro to implement the IObject methods automatically. Put * this at the beginning of your class, specifiying the class name as * the parameter, and it will automatically implement all the IObject * methods. You also need to define an interface map. * * \sa UUID_MAP_BEGIN, UUID_MAP_ENTRY, UUID_MAP_ENTRY_2, UUID_MAP_END */ #define IMPLEMENT_IOBJECT(component) \ private: \ IObjectImplInternal xplc_iobject_internal; \ static const UUID_Info xplc_iobject_uuids[]; \ typedef component ThisXPLCComponent; \ public: \ virtual unsigned int addRef() { \ return ++xplc_iobject_internal.refcount; \ } \ virtual unsigned int release() { \ if(--xplc_iobject_internal.refcount) \ return xplc_iobject_internal.refcount; \ /* protect against re-entering the destructor */ \ xplc_iobject_internal.refcount = 1; \ if(xplc_iobject_internal.weakref) { \ xplc_iobject_internal.weakref->release(); \ xplc_iobject_internal.weakref->object = 0; \ } \ xplcdelete this; \ return 0; \ } \ virtual IObject* getInterface(const UUID& uuid) { \ return xplc_iobject_internal.getInterface(this, uuid, xplc_iobject_uuids); \ } \ virtual IWeakRef* getWeakRef() { \ if(!xplc_iobject_internal.weakref) \ xplc_iobject_internal.weakref = new WeakRef(reinterpret_cast<IObject*>(reinterpret_cast<ptrdiff_t>(this) + xplc_iobject_uuids->delta)); \ xplc_iobject_internal.weakref->addRef(); \ return xplc_iobject_internal.weakref; \ } /** \class WeakRef * * Common implementation of a weak reference. */ class WeakRef: public IWeakRef { IMPLEMENT_IOBJECT(WeakRef); public: /** The object that the weak reference is pointing at. */ IObject* object; virtual IObject* getObject() { if(object) object->addRef(); return object; } /** * Initialize a weak reference. */ WeakRef(IObject* aObj): object(aObj) { } }; /** * %XPLC equivalent to dynamic_cast. This templated function is a * typesafe way to call the getInterface method of a component and * cast it properly. If the component does not support the interface, * a NULL pointer will be returned. */ template<class Interface> Interface* get(IObject* aObj) { if(!aObj) return 0; return static_cast<Interface*>(aObj->getInterface(XPLC_IID<Interface>::get())); } /** * A version of get() that releases its parameter. This templated * function is very similar to the "get" one, except that it * automatically releases the inbound reference, without regard * whether the getInterface actually yielded something. */ template<class Interface> Interface* mutate(IObject* aObj) { Interface* rv; if(!aObj) return 0; rv = static_cast<Interface*>(aObj->getInterface(XPLC_IID<Interface>::get())); aObj->release(); return rv; } #endif /* __XPLC_UTILS_H__ */