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1069 строки
40 KiB
C++
1069 строки
40 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim:set ts=2 sw=2 sts=2 et cindent: */
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/* ***** BEGIN LICENSE BLOCK *****
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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*
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* The contents of this file are subject to the Mozilla Public License Version
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* 1.1 (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.mozilla.org/MPL/
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*
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* Software distributed under the License is distributed on an "AS IS" basis,
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* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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* for the specific language governing rights and limitations under the
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* License.
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*
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* The Original Code is C++ array template.
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*
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* The Initial Developer of the Original Code is Google Inc.
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* Portions created by the Initial Developer are Copyright (C) 2005
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* the Initial Developer. All Rights Reserved.
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*
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* Contributor(s):
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* Darin Fisher <darin@meer.net>
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*
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* Alternatively, the contents of this file may be used under the terms of
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* either the GNU General Public License Version 2 or later (the "GPL"), or
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* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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* in which case the provisions of the GPL or the LGPL are applicable instead
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* of those above. If you wish to allow use of your version of this file only
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* under the terms of either the GPL or the LGPL, and not to allow others to
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* use your version of this file under the terms of the MPL, indicate your
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* decision by deleting the provisions above and replace them with the notice
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* and other provisions required by the GPL or the LGPL. If you do not delete
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* the provisions above, a recipient may use your version of this file under
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* the terms of any one of the MPL, the GPL or the LGPL.
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*
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* ***** END LICENSE BLOCK ***** */
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#ifndef nsTArray_h__
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#define nsTArray_h__
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#include "prtypes.h"
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#include "nsQuickSort.h"
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#include "nsDebug.h"
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#include "nsTraceRefcnt.h"
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#include NEW_H
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//
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// This class serves as a base class for nsTArray. It shouldn't be used
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// directly. It holds common implementation code that does not depend on the
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// element type of the nsTArray.
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//
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class NS_COM_GLUE nsTArray_base {
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public:
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typedef PRUint32 size_type;
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typedef PRUint32 index_type;
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// A special value that is used to indicate an invalid or unknown index
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// into the array.
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enum {
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NoIndex = index_type(-1)
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};
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// @return The number of elements in the array.
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size_type Length() const {
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return mHdr->mLength;
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}
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// @return True if the array is empty or false otherwise.
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PRBool IsEmpty() const {
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return Length() == 0;
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}
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// @return The number of elements that can fit in the array without forcing
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// the array to be re-allocated. The length of an array is always less
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// than or equal to its capacity.
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size_type Capacity() const {
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return mHdr->mCapacity;
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}
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#ifdef DEBUG
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void* DebugGetHeader() const {
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return mHdr;
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}
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#endif
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protected:
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nsTArray_base();
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~nsTArray_base();
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// Resize the storage if necessary to achieve the requested capacity.
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// @param capacity The requested number of array elements.
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// @param elementSize The size of an array element.
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// @return False if insufficient memory is available; true otherwise.
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PRBool EnsureCapacity(size_type capacity, size_type elementSize);
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// Resize the storage to the minimum required amount.
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// @param elementSize The size of an array element.
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void ShrinkCapacity(size_type elementSize);
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// This method may be called to resize a "gap" in the array by shifting
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// elements around. It updates mLength appropriately. If the resulting
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// array has zero elements, then the array's memory is free'd.
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// @param start The starting index of the gap.
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// @param oldLen The current length of the gap.
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// @param newLen The desired length of the gap.
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// @param elementSize The size of an array element.
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void ShiftData(index_type start, size_type oldLen, size_type newLen,
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size_type elementSize);
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// This method increments the length member of the array's header.
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// Note that mHdr may actually be sEmptyHdr in the case where a
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// zero-length array is inserted into our array. But then n should
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// always be 0.
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void IncrementLength(PRUint32 n) {
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NS_ASSERTION(mHdr != &sEmptyHdr || n == 0, "bad data pointer");
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mHdr->mLength += n;
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}
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// This method inserts blank slots into the array.
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// @param index the place to insert the new elements. This must be no
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// greater than the current length of the array.
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// @param count the number of slots to insert
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// @param elementSize the size of an array element.
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PRBool InsertSlotsAt(index_type index, size_type count,
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size_type elementSize);
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protected:
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// NOTE: This method isn't heavily optimized if either array is an
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// nsAutoTArray.
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PRBool SwapArrayElements(nsTArray_base& other, size_type elementSize);
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// Helper function for SwapArrayElements. Ensures that if the array
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// is an nsAutoTArray that it doesn't use the built-in buffer.
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PRBool EnsureNotUsingAutoArrayBuffer(size_type elemSize);
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// We prefix mData with a structure of this type. This is done to minimize
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// the size of the nsTArray object when it is empty.
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struct Header {
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PRUint32 mLength;
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PRUint32 mCapacity : 31;
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PRUint32 mIsAutoArray : 1;
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};
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// Returns true if this nsTArray is an nsAutoTArray with a built-in buffer.
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PRBool IsAutoArray() {
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return mHdr->mIsAutoArray;
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}
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// Dummy struct to get the compiler to simulate the alignment of
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// nsAutoTArray's and nsAutoTPtrArray's mAutoBuf.
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struct AutoArray {
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Header *mHdr;
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PRUint64 aligned;
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};
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// Returns a Header for the built-in buffer of this nsAutoTArray.
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Header* GetAutoArrayBuffer() {
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NS_ASSERTION(IsAutoArray(), "Should be an auto array to call this");
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return reinterpret_cast<Header*>(&(reinterpret_cast<AutoArray*>(&mHdr))->aligned);
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}
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// Returns true if this is an nsAutoTArray and it currently uses the
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// built-in buffer to store its elements.
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PRBool UsesAutoArrayBuffer() {
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return mHdr->mIsAutoArray && mHdr == GetAutoArrayBuffer();
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}
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// This is not const since we may actually write to it. However we will
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// always write to it the same data that it already contains. See
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// IncrementLength
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static Header sEmptyHdr;
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// The array's elements (prefixed with a Header). This pointer is never
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// null. If the array is empty, then this will point to sEmptyHdr.
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Header *mHdr;
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};
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//
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// This class defines convenience functions for element specific operations.
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// Specialize this template if necessary.
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//
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template<class E>
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class nsTArrayElementTraits {
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public:
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// Invoke the default constructor in place.
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static inline void Construct(E *e) {
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// Do NOT call "E()"! That triggers C++ "default initialization"
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// which zeroes out POD ("plain old data") types such as regular ints.
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// We don't want that because it can be a performance issue and people
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// don't expect it; nsTArray should work like a regular C/C++ array in
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// this respect.
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new (static_cast<void *>(e)) E;
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}
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// Invoke the copy-constructor in place.
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template<class A>
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static inline void Construct(E *e, const A &arg) {
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new (static_cast<void *>(e)) E(arg);
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}
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// Invoke the destructor in place.
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static inline void Destruct(E *e) {
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e->~E();
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}
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};
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// This class exists because VC6 cannot handle static template functions.
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// Otherwise, the Compare method would be defined directly on nsTArray.
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template <class E, class Comparator>
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class nsQuickSortComparator {
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public:
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typedef E elem_type;
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// This function is meant to be used with the NS_QuickSort function. It
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// maps the callback API expected by NS_QuickSort to the Comparator API
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// used by nsTArray. See nsTArray::Sort.
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static int Compare(const void* e1, const void* e2, void *data) {
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const Comparator* c = reinterpret_cast<const Comparator*>(data);
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const elem_type* a = static_cast<const elem_type*>(e1);
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const elem_type* b = static_cast<const elem_type*>(e2);
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return c->LessThan(*a, *b) ? -1 : (c->Equals(*a, *b) ? 0 : 1);
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}
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};
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// The default comparator used by nsTArray
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template<class A, class B>
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class nsDefaultComparator {
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public:
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PRBool Equals(const A& a, const B& b) const {
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return a == b;
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}
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PRBool LessThan(const A& a, const B& b) const {
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return a < b;
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}
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};
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//
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// The templatized array class that dynamically resizes its storage as elements
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// are added. This class is designed to behave a bit like std::vector.
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//
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// The template parameter specifies the type of the elements (elem_type), and
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// has the following requirements:
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//
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// elem_type MUST define a copy-constructor.
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// elem_type MAY define operator< for sorting.
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// elem_type MAY define operator== for searching.
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//
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// For methods taking a Comparator instance, the Comparator must be a class
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// defining the following methods:
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//
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// class Comparator {
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// public:
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// /** @return True if the elements are equals; false otherwise. */
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// PRBool Equals(const elem_type& a, const elem_type& b) const;
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//
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// /** @return True if (a < b); false otherwise. */
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// PRBool LessThan(const elem_type& a, const elem_type& b) const;
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// };
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//
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// The Equals method is used for searching, and the LessThan method is used
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// for sorting.
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//
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template<class E>
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class nsTArray : public nsTArray_base {
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public:
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typedef E elem_type;
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typedef nsTArray<E> self_type;
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typedef nsTArrayElementTraits<E> elem_traits;
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//
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// Finalization method
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//
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~nsTArray() { Clear(); }
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//
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// Initialization methods
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//
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nsTArray() {}
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// Initialize this array and pre-allocate some number of elements.
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explicit nsTArray(size_type capacity) {
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SetCapacity(capacity);
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}
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// The array's copy-constructor performs a 'deep' copy of the given array.
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// @param other The array object to copy.
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nsTArray(const self_type& other) {
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AppendElements(other);
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}
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// The array's assignment operator performs a 'deep' copy of the given
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// array. It is optimized to reuse existing storage if possible.
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// @param other The array object to copy.
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nsTArray& operator=(const self_type& other) {
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ReplaceElementsAt(0, Length(), other.Elements(), other.Length());
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return *this;
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}
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// Return true if this array has the same length and the same
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// elements as |other|.
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bool operator==(const self_type& other) const {
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size_type len = Length();
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if (len != other.Length())
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return false;
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// XXX std::equal would be as fast or faster here
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for (index_type i = 0; i < len; ++i)
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if (!(operator[](i) == other[i]))
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return false;
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return true;
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}
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//
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// Accessor methods
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//
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// This method provides direct access to the array elements.
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// @return A pointer to the first element of the array. If the array is
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// empty, then this pointer must not be dereferenced.
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elem_type* Elements() {
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return reinterpret_cast<elem_type *>(mHdr + 1);
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}
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// This method provides direct, readonly access to the array elements.
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// @return A pointer to the first element of the array. If the array is
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// empty, then this pointer must not be dereferenced.
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const elem_type* Elements() const {
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return reinterpret_cast<const elem_type *>(mHdr + 1);
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}
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// This method provides direct access to the i'th element of the array.
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// The given index must be within the array bounds.
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// @param i The index of an element in the array.
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// @return A reference to the i'th element of the array.
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elem_type& ElementAt(index_type i) {
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NS_ASSERTION(i < Length(), "invalid array index");
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return Elements()[i];
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}
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// This method provides direct, readonly access to the i'th element of the
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// array. The given index must be within the array bounds.
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// @param i The index of an element in the array.
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// @return A const reference to the i'th element of the array.
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const elem_type& ElementAt(index_type i) const {
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NS_ASSERTION(i < Length(), "invalid array index");
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return Elements()[i];
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}
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// This method provides direct access to the i'th element of the array in
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// a bounds safe manner. If the requested index is out of bounds the
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// provided default value is returned.
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// @param i The index of an element in the array.
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// @param def The value to return if the index is out of bounds.
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elem_type& SafeElementAt(index_type i, elem_type& def) {
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return i < Length() ? Elements()[i] : def;
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}
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// This method provides direct access to the i'th element of the array in
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// a bounds safe manner. If the requested index is out of bounds the
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// provided default value is returned.
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// @param i The index of an element in the array.
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// @param def The value to return if the index is out of bounds.
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const elem_type& SafeElementAt(index_type i, const elem_type& def) const {
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return i < Length() ? Elements()[i] : def;
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}
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// Shorthand for ElementAt(i)
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elem_type& operator[](index_type i) {
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return ElementAt(i);
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}
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// Shorthand for ElementAt(i)
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const elem_type& operator[](index_type i) const {
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return ElementAt(i);
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}
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//
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// Search methods
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//
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// This method searches for the first element in this array that is equal
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// to the given element.
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// @param item The item to search for.
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// @param comp The Comparator used to determine element equality.
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// @return PR_TRUE if the element was found.
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template<class Item, class Comparator>
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PRBool Contains(const Item& item, const Comparator& comp) const {
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return IndexOf(item, 0, comp) != NoIndex;
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}
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// This method searches for the first element in this array that is equal
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// to the given element. This method assumes that 'operator==' is defined
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// for elem_type.
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// @param item The item to search for.
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// @return PR_TRUE if the element was found.
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template<class Item>
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PRBool Contains(const Item& item) const {
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return IndexOf(item) != NoIndex;
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}
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// This method searches for the offset of the first element in this
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// array that is equal to the given element.
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// @param item The item to search for.
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// @param start The index to start from.
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// @param comp The Comparator used to determine element equality.
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// @return The index of the found element or NoIndex if not found.
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template<class Item, class Comparator>
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index_type IndexOf(const Item& item, index_type start,
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const Comparator& comp) const {
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const elem_type* iter = Elements() + start, *end = Elements() + Length();
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for (; iter != end; ++iter) {
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if (comp.Equals(*iter, item))
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return iter - Elements();
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}
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return NoIndex;
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}
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// This method searches for the offset of the first element in this
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// array that is equal to the given element. This method assumes
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// that 'operator==' is defined for elem_type.
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// @param item The item to search for.
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// @param start The index to start from.
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// @return The index of the found element or NoIndex if not found.
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template<class Item>
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index_type IndexOf(const Item& item, index_type start = 0) const {
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return IndexOf(item, start, nsDefaultComparator<elem_type, Item>());
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}
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// This method searches for the offset of the last element in this
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// array that is equal to the given element.
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// @param item The item to search for.
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// @param start The index to start from. If greater than or equal to the
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// length of the array, then the entire array is searched.
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// @param comp The Comparator used to determine element equality.
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// @return The index of the found element or NoIndex if not found.
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template<class Item, class Comparator>
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index_type LastIndexOf(const Item& item, index_type start,
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const Comparator& comp) const {
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if (start >= Length())
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start = Length() - 1;
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const elem_type* end = Elements() - 1, *iter = end + start + 1;
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for (; iter != end; --iter) {
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if (comp.Equals(*iter, item))
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return iter - Elements();
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}
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return NoIndex;
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}
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// This method searches for the offset of the last element in this
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// array that is equal to the given element. This method assumes
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// that 'operator==' is defined for elem_type.
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// @param item The item to search for.
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// @param start The index to start from. If greater than or equal to the
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// length of the array, then the entire array is searched.
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// @return The index of the found element or NoIndex if not found.
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template<class Item>
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index_type LastIndexOf(const Item& item,
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index_type start = NoIndex) const {
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return LastIndexOf(item, start, nsDefaultComparator<elem_type, Item>());
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}
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// This method searches for the offset for the element in this array
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// that is equal to the given element. The array is assumed to be sorted.
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// @param item The item to search for.
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// @param comp The Comparator used.
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// @return The index of the found element or NoIndex if not found.
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template<class Item, class Comparator>
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index_type BinaryIndexOf(const Item& item, const Comparator& comp) const {
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index_type low = 0, high = Length();
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while (high > low) {
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index_type mid = (high + low) >> 1;
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if (comp.Equals(ElementAt(mid), item))
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return mid;
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if (comp.LessThan(ElementAt(mid), item))
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low = mid + 1;
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else
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high = mid;
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}
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return NoIndex;
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}
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// This method searches for the offset for the element in this array
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// that is equal to the given element. The array is assumed to be sorted.
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// This method assumes that 'operator==' and 'operator<' are defined.
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// @param item The item to search for.
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// @return The index of the found element or NoIndex if not found.
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template<class Item>
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index_type BinaryIndexOf(const Item& item) const {
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return BinaryIndexOf(item, nsDefaultComparator<elem_type, Item>());
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}
|
|
|
|
//
|
|
// Mutation methods
|
|
//
|
|
|
|
// This method replaces a range of elements in this array.
|
|
// @param start The starting index of the elements to replace.
|
|
// @param count The number of elements to replace. This may be zero to
|
|
// insert elements without removing any existing elements.
|
|
// @param array The values to copy into this array. Must be non-null,
|
|
// and these elements must not already exist in the array
|
|
// being modified.
|
|
// @param arrayLen The number of values to copy into this array.
|
|
// @return A pointer to the new elements in the array, or null if
|
|
// the operation failed due to insufficient memory.
|
|
template<class Item>
|
|
elem_type *ReplaceElementsAt(index_type start, size_type count,
|
|
const Item* array, size_type arrayLen) {
|
|
// Adjust memory allocation up-front to catch errors.
|
|
if (!EnsureCapacity(Length() + arrayLen - count, sizeof(elem_type)))
|
|
return nsnull;
|
|
DestructRange(start, count);
|
|
ShiftData(start, count, arrayLen, sizeof(elem_type));
|
|
AssignRange(start, arrayLen, array);
|
|
return Elements() + start;
|
|
}
|
|
|
|
// A variation on the ReplaceElementsAt method defined above.
|
|
template<class Item>
|
|
elem_type *ReplaceElementsAt(index_type start, size_type count,
|
|
const nsTArray<Item>& array) {
|
|
return ReplaceElementsAt(start, count, array.Elements(), array.Length());
|
|
}
|
|
|
|
// A variation on the ReplaceElementsAt method defined above.
|
|
template<class Item>
|
|
elem_type *ReplaceElementsAt(index_type start, size_type count,
|
|
const Item& item) {
|
|
return ReplaceElementsAt(start, count, &item, 1);
|
|
}
|
|
|
|
// A variation on the ReplaceElementsAt method defined above.
|
|
template<class Item>
|
|
elem_type *InsertElementsAt(index_type index, const Item* array,
|
|
size_type arrayLen) {
|
|
return ReplaceElementsAt(index, 0, array, arrayLen);
|
|
}
|
|
|
|
// A variation on the ReplaceElementsAt method defined above.
|
|
template<class Item>
|
|
elem_type *InsertElementsAt(index_type index, const nsTArray<Item>& array) {
|
|
return ReplaceElementsAt(index, 0, array.Elements(), array.Length());
|
|
}
|
|
|
|
// A variation on the ReplaceElementsAt method defined above.
|
|
template<class Item>
|
|
elem_type *InsertElementAt(index_type index, const Item& item) {
|
|
return ReplaceElementsAt(index, 0, &item, 1);
|
|
}
|
|
|
|
// Insert a new element without copy-constructing. This is useful to avoid
|
|
// temporaries.
|
|
// @return A pointer to the newly inserted element, or null on OOM.
|
|
elem_type* InsertElementAt(index_type index) {
|
|
if (!EnsureCapacity(Length() + 1, sizeof(elem_type)))
|
|
return nsnull;
|
|
ShiftData(index, 0, 1, sizeof(elem_type));
|
|
elem_type *elem = Elements() + index;
|
|
elem_traits::Construct(elem);
|
|
return elem;
|
|
}
|
|
|
|
// This method searches for the least index of the greatest
|
|
// element less than or equal to |item|. If |item| is inserted at
|
|
// this index, the array will remain sorted. True is returned iff
|
|
// this index is also equal to |item|. In this case, the returned
|
|
// index may point to the start of multiple copies of |item|.
|
|
// @param item The item to search for.
|
|
// @param comp The Comparator used.
|
|
// @outparam idx The index of greatest element <= to |item|
|
|
// @return True iff |item == array[*idx]|.
|
|
// @precondition The array is sorted
|
|
template<class Item, class Comparator>
|
|
PRBool
|
|
GreatestIndexLtEq(const Item& item,
|
|
const Comparator& comp,
|
|
index_type* idx NS_OUTPARAM) const {
|
|
// Nb: we could replace all the uses of "BinaryIndexOf" with this
|
|
// function, but BinaryIndexOf will be oh-so-slightly faster so
|
|
// it's not strictly desired to do.
|
|
|
|
// invariant: low <= [idx] < high
|
|
index_type low = 0, high = Length();
|
|
while (high > low) {
|
|
index_type mid = (high + low) >> 1;
|
|
if (comp.Equals(ElementAt(mid), item)) {
|
|
// we might have the array [..., 2, 4, 4, 4, 4, 4, 5, ...]
|
|
// and be searching for "4". it's arbitrary where mid ends
|
|
// up here, so we back it up to the first instance to maintain
|
|
// the "least index ..." we promised above.
|
|
do {
|
|
--mid;
|
|
} while (NoIndex != mid && comp.Equals(ElementAt(mid), item));
|
|
*idx = ++mid;
|
|
return PR_TRUE;
|
|
}
|
|
if (comp.LessThan(ElementAt(mid), item))
|
|
// invariant: low <= idx < high
|
|
low = mid + 1;
|
|
else
|
|
// invariant: low <= idx < high
|
|
high = mid;
|
|
}
|
|
// low <= idx < high, so insert at high ("shifting" high up by
|
|
// 1) to maintain invariant.
|
|
// (or insert at low, since low==high; just a matter of taste here.)
|
|
*idx = high;
|
|
return PR_FALSE;
|
|
}
|
|
|
|
// A variation on the GreatestIndexLtEq method defined above.
|
|
template<class Item, class Comparator>
|
|
PRBool
|
|
GreatestIndexLtEq(const Item& item,
|
|
index_type& idx,
|
|
const Comparator& comp) const {
|
|
return GreatestIndexLtEq(item, comp, &idx);
|
|
}
|
|
|
|
// A variation on the GreatestIndexLtEq method defined above.
|
|
template<class Item>
|
|
PRBool
|
|
GreatestIndexLtEq(const Item& item,
|
|
index_type& idx) const {
|
|
return GreatestIndexLtEq(item, nsDefaultComparator<elem_type, Item>(), &idx);
|
|
}
|
|
|
|
// Inserts |item| at such an index to guarantee that if the array
|
|
// was previously sorted, it will remain sorted after this
|
|
// insertion.
|
|
template<class Item, class Comparator>
|
|
elem_type *InsertElementSorted(const Item& item, const Comparator& comp) {
|
|
index_type index;
|
|
GreatestIndexLtEq(item, comp, &index);
|
|
return InsertElementAt(index, item);
|
|
}
|
|
|
|
// A variation on the InsertElementSorted metod defined above.
|
|
template<class Item>
|
|
elem_type *InsertElementSorted(const Item& item) {
|
|
return InsertElementSorted(item, nsDefaultComparator<elem_type, Item>());
|
|
}
|
|
|
|
// This method appends elements to the end of this array.
|
|
// @param array The elements to append to this array.
|
|
// @param arrayLen The number of elements to append to this array.
|
|
// @return A pointer to the new elements in the array, or null if
|
|
// the operation failed due to insufficient memory.
|
|
template<class Item>
|
|
elem_type *AppendElements(const Item* array, size_type arrayLen) {
|
|
if (!EnsureCapacity(Length() + arrayLen, sizeof(elem_type)))
|
|
return nsnull;
|
|
index_type len = Length();
|
|
AssignRange(len, arrayLen, array);
|
|
IncrementLength(arrayLen);
|
|
return Elements() + len;
|
|
}
|
|
|
|
// A variation on the AppendElements method defined above.
|
|
template<class Item>
|
|
elem_type *AppendElements(const nsTArray<Item>& array) {
|
|
return AppendElements(array.Elements(), array.Length());
|
|
}
|
|
|
|
// A variation on the AppendElements method defined above.
|
|
template<class Item>
|
|
elem_type *AppendElement(const Item& item) {
|
|
return AppendElements(&item, 1);
|
|
}
|
|
|
|
// Append new elements without copy-constructing. This is useful to avoid
|
|
// temporaries.
|
|
// @return A pointer to the newly appended elements, or null on OOM.
|
|
elem_type *AppendElements(size_type count) {
|
|
if (!EnsureCapacity(Length() + count, sizeof(elem_type)))
|
|
return nsnull;
|
|
elem_type *elems = Elements() + Length();
|
|
size_type i;
|
|
for (i = 0; i < count; ++i) {
|
|
elem_traits::Construct(elems + i);
|
|
}
|
|
IncrementLength(count);
|
|
return elems;
|
|
}
|
|
|
|
// Append a new element without copy-constructing. This is useful to avoid
|
|
// temporaries.
|
|
// @return A pointer to the newly appended element, or null on OOM.
|
|
elem_type *AppendElement() {
|
|
return AppendElements(1);
|
|
}
|
|
|
|
// Move all elements from another array to the end of this array without
|
|
// calling copy constructors or destructors.
|
|
// @return A pointer to the newly appended elements, or null on OOM.
|
|
template<class Item>
|
|
elem_type *MoveElementsFrom(nsTArray<Item>& array) {
|
|
NS_PRECONDITION(&array != this, "argument must be different array");
|
|
index_type len = Length();
|
|
index_type otherLen = array.Length();
|
|
if (!EnsureCapacity(len + otherLen, sizeof(elem_type)))
|
|
return nsnull;
|
|
memcpy(Elements() + len, array.Elements(), otherLen * sizeof(elem_type));
|
|
IncrementLength(otherLen);
|
|
array.ShiftData(0, otherLen, 0, sizeof(elem_type));
|
|
return Elements() + len;
|
|
}
|
|
|
|
// This method removes a range of elements from this array.
|
|
// @param start The starting index of the elements to remove.
|
|
// @param count The number of elements to remove.
|
|
void RemoveElementsAt(index_type start, size_type count) {
|
|
NS_ASSERTION(count == 0 || start < Length(), "Invalid start index");
|
|
NS_ASSERTION(start + count <= Length(), "Invalid length");
|
|
DestructRange(start, count);
|
|
ShiftData(start, count, 0, sizeof(elem_type));
|
|
}
|
|
|
|
// A variation on the RemoveElementsAt method defined above.
|
|
void RemoveElementAt(index_type index) {
|
|
RemoveElementsAt(index, 1);
|
|
}
|
|
|
|
// A variation on the RemoveElementsAt method defined above.
|
|
void Clear() {
|
|
RemoveElementsAt(0, Length());
|
|
}
|
|
|
|
// This helper function combines IndexOf with RemoveElementAt to "search
|
|
// and destroy" the first element that is equal to the given element.
|
|
// @param item The item to search for.
|
|
// @param comp The Comparator used to determine element equality.
|
|
// @return PR_TRUE if the element was found
|
|
template<class Item, class Comparator>
|
|
PRBool RemoveElement(const Item& item, const Comparator& comp) {
|
|
index_type i = IndexOf(item, 0, comp);
|
|
if (i == NoIndex)
|
|
return PR_FALSE;
|
|
|
|
RemoveElementAt(i);
|
|
return PR_TRUE;
|
|
}
|
|
|
|
// A variation on the RemoveElement method defined above that assumes
|
|
// that 'operator==' is defined for elem_type.
|
|
template<class Item>
|
|
PRBool RemoveElement(const Item& item) {
|
|
return RemoveElement(item, nsDefaultComparator<elem_type, Item>());
|
|
}
|
|
|
|
// This helper function combines GreatestIndexLtEq with
|
|
// RemoveElementAt to "search and destroy" the first element that
|
|
// is equal to the given element.
|
|
// @param item The item to search for.
|
|
// @param comp The Comparator used to determine element equality.
|
|
// @return PR_TRUE if the element was found
|
|
template<class Item, class Comparator>
|
|
PRBool RemoveElementSorted(const Item& item, const Comparator& comp) {
|
|
index_type index;
|
|
PRBool found = GreatestIndexLtEq(item, comp, &index);
|
|
if (found)
|
|
RemoveElementAt(index);
|
|
return found;
|
|
}
|
|
|
|
// A variation on the RemoveElementSorted method defined above.
|
|
template<class Item>
|
|
PRBool RemoveElementSorted(const Item& item) {
|
|
return RemoveElementSorted(item, nsDefaultComparator<elem_type, Item>());
|
|
}
|
|
|
|
// This method causes the elements contained in this array and the given
|
|
// array to be swapped.
|
|
// NOTE: This method isn't heavily optimized if either array is an
|
|
// nsAutoTArray.
|
|
PRBool SwapElements(self_type& other) {
|
|
return SwapArrayElements(other, sizeof(elem_type));
|
|
}
|
|
|
|
//
|
|
// Allocation
|
|
//
|
|
|
|
// This method may increase the capacity of this array object by the
|
|
// specified amount. This method may be called in advance of several
|
|
// AppendElement operations to minimize heap re-allocations. This method
|
|
// will not reduce the number of elements in this array.
|
|
// @param capacity The desired capacity of this array.
|
|
// @return True if the operation succeeded; false if we ran out of memory
|
|
PRBool SetCapacity(size_type capacity) {
|
|
return EnsureCapacity(capacity, sizeof(elem_type));
|
|
}
|
|
|
|
// This method modifies the length of the array. If the new length is
|
|
// larger than the existing length of the array, then new elements will be
|
|
// constructed using elem_type's default constructor. Otherwise, this call
|
|
// removes elements from the array (see also RemoveElementsAt).
|
|
// @param newLen The desired length of this array.
|
|
// @return True if the operation succeeded; false otherwise.
|
|
// See also TruncateLength if the new length is guaranteed to be
|
|
// smaller than the old.
|
|
PRBool SetLength(size_type newLen) {
|
|
size_type oldLen = Length();
|
|
if (newLen > oldLen) {
|
|
return InsertElementsAt(oldLen, newLen - oldLen) != nsnull;
|
|
}
|
|
|
|
TruncateLength(newLen);
|
|
return PR_TRUE;
|
|
}
|
|
|
|
// This method modifies the length of the array, but may only be
|
|
// called when the new length is shorter than the old. It can
|
|
// therefore be called when elem_type has no default constructor,
|
|
// unlike SetLength. It removes elements from the array (see also
|
|
// RemoveElementsAt).
|
|
// @param newLen The desired length of this array.
|
|
void TruncateLength(size_type newLen) {
|
|
size_type oldLen = Length();
|
|
NS_ABORT_IF_FALSE(newLen <= oldLen,
|
|
"caller should use SetLength instead");
|
|
RemoveElementsAt(newLen, oldLen - newLen);
|
|
}
|
|
|
|
// This method ensures that the array has length at least the given
|
|
// length. If the current length is shorter than the given length,
|
|
// then new elements will be constructed using elem_type's default
|
|
// constructor.
|
|
// @param minLen The desired minimum length of this array.
|
|
// @return True if the operation succeeded; false otherwise.
|
|
PRBool EnsureLengthAtLeast(size_type minLen) {
|
|
size_type oldLen = Length();
|
|
if (minLen > oldLen) {
|
|
return InsertElementsAt(oldLen, minLen - oldLen) != nsnull;
|
|
}
|
|
return PR_TRUE;
|
|
}
|
|
|
|
// This method inserts elements into the array, constructing
|
|
// them using elem_type's default constructor.
|
|
// @param index the place to insert the new elements. This must be no
|
|
// greater than the current length of the array.
|
|
// @param count the number of elements to insert
|
|
elem_type *InsertElementsAt(index_type index, size_type count) {
|
|
if (!nsTArray_base::InsertSlotsAt(index, count, sizeof(elem_type))) {
|
|
return nsnull;
|
|
}
|
|
|
|
// Initialize the extra array elements
|
|
elem_type *iter = Elements() + index, *end = iter + count;
|
|
for (; iter != end; ++iter) {
|
|
elem_traits::Construct(iter);
|
|
}
|
|
|
|
return Elements() + index;
|
|
}
|
|
|
|
// This method inserts elements into the array, constructing them
|
|
// elem_type's copy constructor (or whatever one-arg constructor
|
|
// happens to match the Item type).
|
|
// @param index the place to insert the new elements. This must be no
|
|
// greater than the current length of the array.
|
|
// @param count the number of elements to insert.
|
|
// @param item the value to use when constructing the new elements.
|
|
template<class Item>
|
|
elem_type *InsertElementsAt(index_type index, size_type count,
|
|
const Item& item) {
|
|
if (!nsTArray_base::InsertSlotsAt(index, count, sizeof(elem_type))) {
|
|
return nsnull;
|
|
}
|
|
|
|
// Initialize the extra array elements
|
|
elem_type *iter = Elements() + index, *end = iter + count;
|
|
for (; iter != end; ++iter) {
|
|
elem_traits::Construct(iter, item);
|
|
}
|
|
|
|
return Elements() + index;
|
|
}
|
|
|
|
// This method may be called to minimize the memory used by this array.
|
|
void Compact() {
|
|
ShrinkCapacity(sizeof(elem_type));
|
|
}
|
|
|
|
//
|
|
// Sorting
|
|
//
|
|
|
|
// This method sorts the elements of the array. It uses the LessThan
|
|
// method defined on the given Comparator object to collate elements.
|
|
// @param comp The Comparator used to collate elements.
|
|
template<class Comparator>
|
|
void Sort(const Comparator& comp) {
|
|
NS_QuickSort(Elements(), Length(), sizeof(elem_type),
|
|
nsQuickSortComparator<elem_type, Comparator>::Compare,
|
|
const_cast<Comparator*>(&comp));
|
|
}
|
|
|
|
// A variation on the Sort method defined above that assumes that
|
|
// 'operator<' is defined for elem_type.
|
|
void Sort() {
|
|
Sort(nsDefaultComparator<elem_type, elem_type>());
|
|
}
|
|
|
|
//
|
|
// Binary Heap
|
|
//
|
|
|
|
// Sorts the array into a binary heap.
|
|
// @param comp The Comparator used to create the heap
|
|
template<class Comparator>
|
|
void MakeHeap(const Comparator& comp) {
|
|
if (!Length()) {
|
|
return;
|
|
}
|
|
index_type index = (Length() - 1) / 2;
|
|
do {
|
|
SiftDown(index, comp);
|
|
} while (index--);
|
|
}
|
|
|
|
// A variation on the MakeHeap method defined above.
|
|
void MakeHeap() {
|
|
MakeHeap(nsDefaultComparator<elem_type, elem_type>());
|
|
}
|
|
|
|
// Adds an element to the heap
|
|
// @param item The item to add
|
|
// @param comp The Comparator used to sift-up the item
|
|
template<class Item, class Comparator>
|
|
elem_type *PushHeap(const Item& item, const Comparator& comp) {
|
|
if (!nsTArray_base::InsertSlotsAt(Length(), 1, sizeof(elem_type))) {
|
|
return nsnull;
|
|
}
|
|
// Sift up the new node
|
|
elem_type *elem = Elements();
|
|
index_type index = Length() - 1;
|
|
index_type parent_index = (index - 1) / 2;
|
|
while (index && comp.LessThan(elem[parent_index], item)) {
|
|
elem[index] = elem[parent_index];
|
|
index = parent_index;
|
|
parent_index = (index - 1) / 2;
|
|
}
|
|
elem[index] = item;
|
|
return &elem[index];
|
|
}
|
|
|
|
// A variation on the PushHeap method defined above.
|
|
template<class Item>
|
|
elem_type *PushHeap(const Item& item) {
|
|
return PushHeap(item, nsDefaultComparator<elem_type, Item>());
|
|
}
|
|
|
|
// Delete the root of the heap and restore the heap
|
|
// @param comp The Comparator used to restore the heap
|
|
template<class Comparator>
|
|
void PopHeap(const Comparator& comp) {
|
|
if (!Length()) {
|
|
return;
|
|
}
|
|
index_type last_index = Length() - 1;
|
|
elem_type *elem = Elements();
|
|
elem[0] = elem[last_index];
|
|
TruncateLength(last_index);
|
|
if (Length()) {
|
|
SiftDown(0, comp);
|
|
}
|
|
}
|
|
|
|
// A variation on the PopHeap method defined above.
|
|
void PopHeap() {
|
|
PopHeap(nsDefaultComparator<elem_type, elem_type>());
|
|
}
|
|
|
|
protected:
|
|
|
|
// This method invokes elem_type's destructor on a range of elements.
|
|
// @param start The index of the first element to destroy.
|
|
// @param count The number of elements to destroy.
|
|
void DestructRange(index_type start, size_type count) {
|
|
elem_type *iter = Elements() + start, *end = iter + count;
|
|
for (; iter != end; ++iter) {
|
|
elem_traits::Destruct(iter);
|
|
}
|
|
}
|
|
|
|
// This method invokes elem_type's copy-constructor on a range of elements.
|
|
// @param start The index of the first element to construct.
|
|
// @param count The number of elements to construct.
|
|
// @param values The array of elements to copy.
|
|
template<class Item>
|
|
void AssignRange(index_type start, size_type count,
|
|
const Item *values) {
|
|
elem_type *iter = Elements() + start, *end = iter + count;
|
|
for (; iter != end; ++iter, ++values) {
|
|
elem_traits::Construct(iter, *values);
|
|
}
|
|
}
|
|
|
|
// This method sifts an item down to its proper place in a binary heap
|
|
// @param index The index of the node to start sifting down from
|
|
// @param comp The Comparator used to sift down
|
|
template<class Comparator>
|
|
void SiftDown(index_type index, const Comparator& comp) {
|
|
elem_type *elem = Elements();
|
|
elem_type item = elem[index];
|
|
index_type end = Length() - 1;
|
|
while ((index * 2) < end) {
|
|
const index_type left = (index * 2) + 1;
|
|
const index_type right = (index * 2) + 2;
|
|
const index_type parent_index = index;
|
|
if (comp.LessThan(item, elem[left])) {
|
|
if (left < end &&
|
|
comp.LessThan(elem[left], elem[right])) {
|
|
index = right;
|
|
} else {
|
|
index = left;
|
|
}
|
|
} else if (left < end &&
|
|
comp.LessThan(item, elem[right])) {
|
|
index = right;
|
|
} else {
|
|
break;
|
|
}
|
|
elem[parent_index] = elem[index];
|
|
}
|
|
elem[index] = item;
|
|
}
|
|
};
|
|
|
|
template<class E, PRUint32 N>
|
|
class nsAutoTArray : public nsTArray<E> {
|
|
public:
|
|
typedef nsTArray<E> base_type;
|
|
typedef typename base_type::Header Header;
|
|
typedef typename base_type::elem_type elem_type;
|
|
|
|
nsAutoTArray() {
|
|
base_type::mHdr = reinterpret_cast<Header*>(&mAutoBuf);
|
|
base_type::mHdr->mLength = 0;
|
|
base_type::mHdr->mCapacity = N;
|
|
base_type::mHdr->mIsAutoArray = 1;
|
|
|
|
NS_ASSERTION(base_type::GetAutoArrayBuffer() ==
|
|
reinterpret_cast<Header*>(&mAutoBuf),
|
|
"GetAutoArrayBuffer needs to be fixed");
|
|
}
|
|
|
|
protected:
|
|
union {
|
|
char mAutoBuf[sizeof(Header) + N * sizeof(elem_type)];
|
|
PRUint64 dummy;
|
|
};
|
|
};
|
|
|
|
// specialization for N = 0. this makes the inheritance model easier for
|
|
// templated users of nsAutoTArray.
|
|
template<class E>
|
|
class nsAutoTArray<E, 0> : public nsTArray<E> {
|
|
public:
|
|
nsAutoTArray() {}
|
|
};
|
|
|
|
#endif // nsTArray_h__
|