Back to index

lightning-sunbird  0.9+nobinonly
txStack.h
Go to the documentation of this file.
00001 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
00002 /* ***** BEGIN LICENSE BLOCK *****
00003  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
00004  *
00005  * The contents of this file are subject to the Mozilla Public License Version
00006  * 1.1 (the "License"); you may not use this file except in compliance with
00007  * the License. You may obtain a copy of the License at
00008  * http://www.mozilla.org/MPL/
00009  *
00010  * Software distributed under the License is distributed on an "AS IS" basis,
00011  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
00012  * for the specific language governing rights and limitations under the
00013  * License.
00014  *
00015  * The Original Code is TransforMiiX XSLT processor code.
00016  *
00017  * The Initial Developer of the Original Code is
00018  * Netscape Communications Corporation.
00019  * Portions created by the Initial Developer are Copyright (C) 2002
00020  * the Initial Developer. All Rights Reserved.
00021  *
00022  * Contributor(s):
00023  *   Peter Van der Beken <peterv@propagandism.org>
00024  *
00025  * Alternatively, the contents of this file may be used under the terms of
00026  * either the GNU General Public License Version 2 or later (the "GPL"), or
00027  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
00028  * in which case the provisions of the GPL or the LGPL are applicable instead
00029  * of those above. If you wish to allow use of your version of this file only
00030  * under the terms of either the GPL or the LGPL, and not to allow others to
00031  * use your version of this file under the terms of the MPL, indicate your
00032  * decision by deleting the provisions above and replace them with the notice
00033  * and other provisions required by the GPL or the LGPL. If you do not delete
00034  * the provisions above, a recipient may use your version of this file under
00035  * the terms of any one of the MPL, the GPL or the LGPL.
00036  *
00037  * ***** END LICENSE BLOCK ***** */
00038 
00039 #ifndef txStack_h___
00040 #define txStack_h___
00041 
00042 #include "nsVoidArray.h"
00043 
00044 class txStack : private nsVoidArray
00045 {
00046 public:
00053     inline void* peek()
00054     {
00055         NS_ASSERTION(!isEmpty(), "peeking at empty stack");
00056         return ElementAt(Count() - 1);
00057     }
00058 
00065     inline nsresult push(void* aObject)
00066     {
00067         return InsertElementAt(aObject, Count()) ? NS_OK :
00068                                                    NS_ERROR_OUT_OF_MEMORY;
00069     }
00070 
00077     inline void* pop()
00078     {
00079         NS_ASSERTION(!isEmpty(), "popping from empty stack");
00080         const PRInt32 count = Count() - 1;
00081         void* object = ElementAt(count);
00082         RemoveElementsAt(count, 1);
00083         return object;
00084     }
00085 
00091     inline PRBool isEmpty()
00092     {
00093         return (Count() <= 0);
00094     }
00095 
00101     inline PRInt32 size()
00102     {
00103         return Count();
00104     }
00105 
00106 private:
00107     friend class txStackIterator;
00108 };
00109 
00110 class txStackIterator
00111 {
00112 public:
00118     inline
00119     txStackIterator(txStack* aStack) : mStack(aStack),
00120                                        mPosition(0)
00121     {
00122     }
00123 
00129     inline PRBool hasNext()
00130     {
00131         return (mPosition < mStack->Count());
00132     }
00133 
00139     inline void* next()
00140     {
00141         if (mPosition == mStack->Count()) {
00142             return nsnull;
00143         }
00144         return mStack->ElementAt(mPosition++);
00145     }
00146 
00147 private:
00148     txStack* mStack;
00149     PRInt32 mPosition;
00150 };
00151 
00152 #endif /* txStack_h___ */