base/memory/scoped_vector.h

   1 // Copyright (c) 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 BASE_MEMORY_SCOPED_VECTOR_H_
   6 #define BASE_MEMORY_SCOPED_VECTOR_H_
   7
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "base/logging.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/move.h"
  14 #include "base/stl_util.h"
  15
  16 // ScopedVector wraps a vector deleting the elements from its
  17 // destructor.
  18 template <class T>
  19 class ScopedVector {
  20   MOVE_ONLY_TYPE_FOR_CPP_03(ScopedVector, RValue)
  21
  22  public:
  23   typedef typename std::vector<T*>::allocator_type allocator_type;
  24   typedef typename std::vector<T*>::size_type size_type;
  25   typedef typename std::vector<T*>::difference_type difference_type;
  26   typedef typename std::vector<T*>::pointer pointer;
  27   typedef typename std::vector<T*>::const_pointer const_pointer;
  28   typedef typename std::vector<T*>::reference reference;
  29   typedef typename std::vector<T*>::const_reference const_reference;
  30   typedef typename std::vector<T*>::value_type value_type;
  31   typedef typename std::vector<T*>::iterator iterator;
  32   typedef typename std::vector<T*>::const_iterator const_iterator;
  33   typedef typename std::vector<T*>::reverse_iterator reverse_iterator;
  34   typedef typename std::vector<T*>::const_reverse_iterator
  35       const_reverse_iterator;
  36
  37   ScopedVector() {}
  38   ~ScopedVector() { clear(); }
  39   ScopedVector(RValue other) { swap(*other.object); }
  40
  41   ScopedVector& operator=(RValue rhs) {
  42     swap(*rhs.object);
  43     return *this;
  44   }
  45
  46   reference operator[](size_t index) { return v_[index]; }
  47   const_reference operator[](size_t index) const { return v_[index]; }
  48
  49   bool empty() const { return v_.empty(); }
  50   size_t size() const { return v_.size(); }
  51
  52   reverse_iterator rbegin() { return v_.rbegin(); }
  53   const_reverse_iterator rbegin() const { return v_.rbegin(); }
  54   reverse_iterator rend() { return v_.rend(); }
  55   const_reverse_iterator rend() const { return v_.rend(); }
  56
  57   iterator begin() { return v_.begin(); }
  58   const_iterator begin() const { return v_.begin(); }
  59   iterator end() { return v_.end(); }
  60   const_iterator end() const { return v_.end(); }
  61
  62   const_reference front() const { return v_.front(); }
  63   reference front() { return v_.front(); }
  64   const_reference back() const { return v_.back(); }
  65   reference back() { return v_.back(); }
  66
  67   void push_back(T* elem) { v_.push_back(elem); }
  68   void push_back(scoped_ptr<T> elem) { v_.push_back(elem.release()); }
  69
  70   void pop_back() {
  71     DCHECK(!empty());
  72     delete v_.back();
  73     v_.pop_back();
  74   }
  75
  76   std::vector<T*>& get() { return v_; }
  77   const std::vector<T*>& get() const { return v_; }
  78   void swap(std::vector<T*>& other) { v_.swap(other); }
  79   void swap(ScopedVector<T>& other) { v_.swap(other.v_); }
  80   void release(std::vector<T*>* out) {
  81     out->swap(v_);
  82     v_.clear();
  83   }
  84
  85   void reserve(size_t capacity) { v_.reserve(capacity); }
  86
  87   // Resize, deleting elements in the disappearing range if we are shrinking.
  88   void resize(size_t new_size) {
  89     if (v_.size() > new_size)
  90       STLDeleteContainerPointers(v_.begin() + new_size, v_.end());
  91     v_.resize(new_size);
  92   }
  93
  94   template<typename InputIterator>
  95   void assign(InputIterator begin, InputIterator end) {
  96     v_.assign(begin, end);
  97   }
  98
  99   void clear() { STLDeleteElements(&v_); }
 100
 101   // Like |clear()|, but doesn't delete any elements.
 102   void weak_clear() { v_.clear(); }
 103
 104   // Lets the ScopedVector take ownership of |x|.
 105   iterator insert(iterator position, T* x) {
 106     return v_.insert(position, x);
 107   }
 108
 109   iterator insert(iterator position, scoped_ptr<T> x) {
 110     return v_.insert(position, x.release());
 111   }
 112
 113   // Lets the ScopedVector take ownership of elements in [first,last).
 114   template<typename InputIterator>
 115   void insert(iterator position, InputIterator first, InputIterator last) {
 116     v_.insert(position, first, last);
 117   }
 118
 119   iterator erase(iterator position) {
 120     delete *position;
 121     return v_.erase(position);
 122   }
 123
 124   iterator erase(iterator first, iterator last) {
 125     STLDeleteContainerPointers(first, last);
 126     return v_.erase(first, last);
 127   }
 128
 129   // Like |erase()|, but doesn't delete the element at |position|.
 130   iterator weak_erase(iterator position) {
 131     return v_.erase(position);
 132   }
 133
 134   // Like |erase()|, but doesn't delete the elements in [first, last).
 135   iterator weak_erase(iterator first, iterator last) {
 136     return v_.erase(first, last);
 137   }
 138
 139  private:
 140   std::vector<T*> v_;
 141 };
 142
 143 #endif  // BASE_MEMORY_SCOPED_VECTOR_H_