cc/base/scoped_ptr_vector.h

   1 // Copyright 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CC_BASE_SCOPED_PTR_VECTOR_H_
   6 #define CC_BASE_SCOPED_PTR_VECTOR_H_
   7
   8 #include <algorithm>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/logging.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/stl_util.h"
  15
  16 namespace cc {
  17
  18 // This type acts like a vector<scoped_ptr> based on top of std::vector. The
  19 // ScopedPtrVector has ownership of all elements in the vector.
  20 template <typename T>
  21 class ScopedPtrVector {
  22  public:
  23   typedef typename std::vector<T*>::const_iterator const_iterator;
  24   typedef typename std::vector<T*>::reverse_iterator reverse_iterator;
  25   typedef typename std::vector<T*>::const_reverse_iterator
  26       const_reverse_iterator;
  27
  28 #if defined(OS_ANDROID)
  29   // On Android the iterator is not a class, so we can't block assignment.
  30   typedef typename std::vector<T*>::iterator iterator;
  31 #else
  32   // Ban setting values on the iterator directly. New pointers must be passed
  33   // to methods on the ScopedPtrVector class to appear in the vector.
  34   class iterator : public std::vector<T*>::iterator {
  35    public:
  36     iterator(const typename std::vector<T*>::iterator& other)
  37         : std::vector<T*>::iterator(other) {}
  38     T* const& operator*() { return std::vector<T*>::iterator::operator*(); }
  39   };
  40 #endif
  41
  42   ScopedPtrVector() {}
  43
  44   ~ScopedPtrVector() { clear(); }
  45
  46   size_t size() const {
  47     return data_.size();
  48   }
  49
  50   T* at(size_t index) const {
  51     DCHECK(index < size());
  52     return data_[index];
  53   }
  54
  55   T* operator[](size_t index) const {
  56     return at(index);
  57   }
  58
  59   T* front() const {
  60     DCHECK(!empty());
  61     return at(0);
  62   }
  63
  64   T* back() const {
  65     DCHECK(!empty());
  66     return at(size() - 1);
  67   }
  68
  69   bool empty() const {
  70     return data_.empty();
  71   }
  72
  73   scoped_ptr<T> take(iterator position) {
  74     if (position == end())
  75       return scoped_ptr<T>(NULL);
  76     DCHECK(position < end());
  77
  78     typename std::vector<T*>::iterator writable_position = position;
  79     scoped_ptr<T> ret(*writable_position);
  80     *writable_position = NULL;
  81     return ret.Pass();
  82   }
  83
  84   scoped_ptr<T> take_back() {
  85     DCHECK(!empty());
  86     if (empty())
  87       return scoped_ptr<T>(NULL);
  88     return take(end() - 1);
  89   }
  90
  91   void erase(iterator position) {
  92     if (position == end())
  93       return;
  94     typename std::vector<T*>::iterator writable_position = position;
  95     delete *writable_position;
  96     data_.erase(position);
  97   }
  98
  99   void erase(iterator first, iterator last) {
 100     DCHECK(first <= last);
 101     for (iterator it = first; it != last; ++it) {
 102       DCHECK(it < end());
 103
 104       typename std::vector<T*>::iterator writable_it = it;
 105       delete *writable_it;
 106     }
 107     data_.erase(first, last);
 108   }
 109
 110   void reserve(size_t size) {
 111     data_.reserve(size);
 112   }
 113
 114   void clear() {
 115     STLDeleteElements(&data_);
 116   }
 117
 118   void push_back(scoped_ptr<T> item) {
 119     data_.push_back(item.release());
 120   }
 121
 122   void pop_back() {
 123     delete data_.back();
 124     data_.pop_back();
 125   }
 126
 127   void insert(iterator position, scoped_ptr<T> item) {
 128     DCHECK(position <= end());
 129     data_.insert(position, item.release());
 130   }
 131
 132   void swap(ScopedPtrVector<T>& other) {
 133     data_.swap(other.data_);
 134   }
 135
 136   void swap(iterator a, iterator b) {
 137     DCHECK(a < end());
 138     DCHECK(b < end());
 139     if (a == end() || b == end() || a == b)
 140       return;
 141     typename std::vector<T*>::iterator writable_a = a;
 142     typename std::vector<T*>::iterator writable_b = b;
 143     std::swap(*writable_a, *writable_b);
 144   }
 145
 146   template<class Compare>
 147   inline void sort(Compare comp) {
 148     std::sort(data_.begin(), data_.end(), comp);
 149   }
 150
 151   iterator begin() { return static_cast<iterator>(data_.begin()); }
 152   const_iterator begin() const { return data_.begin(); }
 153   iterator end() { return static_cast<iterator>(data_.end()); }
 154   const_iterator end() const { return data_.end(); }
 155
 156   reverse_iterator rbegin() { return data_.rbegin(); }
 157   const_reverse_iterator rbegin() const { return data_.rbegin(); }
 158   reverse_iterator rend() { return data_.rend(); }
 159   const_reverse_iterator rend() const { return data_.rend(); }
 160
 161  private:
 162   std::vector<T*> data_;
 163
 164   DISALLOW_COPY_AND_ASSIGN(ScopedPtrVector);
 165 };
 166
 167 }  // namespace cc
 168
 169 #endif  // CC_BASE_SCOPED_PTR_VECTOR_H_