DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Implementation

Mercurial (dcc6d7a0dc00)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/**
 * MODULE NOTES:
 *
 * The Deque is a very small, very efficient container object
 * than can hold elements of type void*, offering the following features:
 *    Its interface supports pushing and popping of elements.
 *    It can iterate (via an interator class) its elements.
 *    When full, it can efficiently resize dynamically.
 *
 *
 * NOTE: The only bit of trickery here is that this deque is
 * built upon a ring-buffer. Like all ring buffers, the first
 * element may not be at index[0]. The mOrigin member determines
 * where the first child is. This point is quietly hidden from
 * customers of this class.
 *
 */

#ifndef _NSDEQUE
#define _NSDEQUE

#include "nscore.h"
#include "nsDebug.h"
#include "mozilla/Attributes.h"
#include "mozilla/fallible.h"
#include "mozilla/MemoryReporting.h"

/**
 * The nsDequeFunctor class is used when you want to create
 * callbacks between the deque and your generic code.
 * Use these objects in a call to ForEach();
 *
 */

class nsDequeFunctor
{
public:
  virtual void* operator()(void* aObject) = 0;
  virtual ~nsDequeFunctor() {}
};

/******************************************************
 * Here comes the nsDeque class itself...
 ******************************************************/

/**
 * The deque (double-ended queue) class is a common container type,
 * whose behavior mimics a line in your favorite checkout stand.
 * Classic CS describes the common behavior of a queue as FIFO.
 * A deque allows insertion and removal at both ends of
 * the container.
 *
 * The deque stores pointers to items.
 */

class nsDequeIterator;

class nsDeque
{
  typedef mozilla::fallible_t fallible_t;
public:
  explicit nsDeque(nsDequeFunctor* aDeallocator = nullptr);
  ~nsDeque();

  /**
   * Returns the number of elements currently stored in
   * this deque.
   *
   * @return  number of elements currently in the deque
   */
  inline size_t GetSize() const { return mSize; }

  /**
   * Appends new member at the end of the deque.
   *
   * @param   item to store in deque
   */
  void Push(void* aItem)
  {
    if (!Push(aItem, mozilla::fallible)) {
      NS_ABORT_OOM(mSize * sizeof(void*));
    }
  }

  MOZ_WARN_UNUSED_RESULT bool Push(void* aItem, const fallible_t&);

  /**
   * Inserts new member at the front of the deque.
   *
   * @param   item to store in deque
   */
  void PushFront(void* aItem)
  {
    if (!PushFront(aItem, mozilla::fallible)) {
      NS_ABORT_OOM(mSize * sizeof(void*));
    }
  }

  MOZ_WARN_UNUSED_RESULT bool PushFront(void* aItem, const fallible_t&);

  /**
   * Remove and return the last item in the container.
   *
   * @return  the item that was the last item in container
   */
  void* Pop();

  /**
   * Remove and return the first item in the container.
   *
   * @return  the item that was first item in container
   */
  void* PopFront();

  /**
   * Retrieve the bottom item without removing it.
   *
   * @return  the first item in container
   */

  void* Peek();
  /**
   * Return topmost item without removing it.
   *
   * @return  the first item in container
   */
  void* PeekFront();

  /**
   * Retrieve a member from the deque without removing it.
   *
   * @param   index of desired item
   * @return  element in list
   */
  void* ObjectAt(size_t aIndex) const;

  /**
   * Remove and delete all items from container.
   * Deletes are handled by the deallocator nsDequeFunctor
   * which is specified at deque construction.
   */
  void Erase();

  /**
   * Call this method when you want to iterate all the
   * members of the container, passing a functor along
   * to call your code.
   *
   * @param   aFunctor object to call for each member
   */
  void ForEach(nsDequeFunctor& aFunctor) const;

  size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
  size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;

protected:
  size_t         mSize;
  size_t         mCapacity;
  size_t         mOrigin;
  nsDequeFunctor* mDeallocator;
  void*           mBuffer[8];
  void**          mData;

private:

  /**
   * Copy constructor (PRIVATE)
   *
   * @param aOther another deque
   */
  nsDeque(const nsDeque& aOther);

  /**
   * Deque assignment operator (PRIVATE)
   *
   * @param aOther another deque
   * @return *this
   */
  nsDeque& operator=(const nsDeque& aOther);

  bool GrowCapacity();
  void SetDeallocator(nsDequeFunctor* aDeallocator);

  /**
   * Remove all items from container without destroying them.
   */
  void Empty();
};
#endif