1 /*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #ifndef ART_LIBARTBASE_BASE_DCHECKED_VECTOR_H_
18 #define ART_LIBARTBASE_BASE_DCHECKED_VECTOR_H_
19
20 #include <algorithm>
21 #include <type_traits>
22 #include <vector>
23
24 #include <android-base/logging.h>
25
26 namespace art {
27
28 // Template class serving as a replacement for std::vector<> but adding
29 // DCHECK()s for the subscript operator, front(), back(), pop_back(),
30 // and for insert()/emplace()/erase() positions.
31 //
32 // Note: The element accessor at() is specified as throwing std::out_of_range
33 // but we do not use exceptions, so this accessor is deliberately hidden.
34 // Note: The common pattern &v[0] used to retrieve pointer to the data is not
35 // valid for an empty dchecked_vector<>. Use data() to avoid checking empty().
36 template <typename T, typename Alloc = std::allocator<T>>
37 class dchecked_vector : private std::vector<T, Alloc> {
38 private:
39 // std::vector<> has a slightly different specialization for bool. We don't provide that.
40 static_assert(!std::is_same<T, bool>::value, "Not implemented for bool.");
41 using Base = std::vector<T, Alloc>;
42
43 public:
44 using typename Base::value_type;
45 using typename Base::allocator_type;
46 using typename Base::reference;
47 using typename Base::const_reference;
48 using typename Base::pointer;
49 using typename Base::const_pointer;
50 using typename Base::iterator;
51 using typename Base::const_iterator;
52 using typename Base::reverse_iterator;
53 using typename Base::const_reverse_iterator;
54 using typename Base::size_type;
55 using typename Base::difference_type;
56
57 // Construct/copy/destroy.
dchecked_vector()58 dchecked_vector()
59 : Base() { }
dchecked_vector(const allocator_type & alloc)60 explicit dchecked_vector(const allocator_type& alloc)
61 : Base(alloc) { }
62 explicit dchecked_vector(size_type n, const allocator_type& alloc = allocator_type())
Base(n,alloc)63 : Base(n, alloc) { }
64 dchecked_vector(size_type n,
65 const value_type& value,
66 const allocator_type& alloc = allocator_type())
Base(n,value,alloc)67 : Base(n, value, alloc) { }
68 template <typename InputIterator>
69 dchecked_vector(InputIterator first,
70 InputIterator last,
71 const allocator_type& alloc = allocator_type())
Base(first,last,alloc)72 : Base(first, last, alloc) { }
dchecked_vector(const dchecked_vector & src)73 dchecked_vector(const dchecked_vector& src)
74 : Base(src) { }
dchecked_vector(const dchecked_vector & src,const allocator_type & alloc)75 dchecked_vector(const dchecked_vector& src, const allocator_type& alloc)
76 : Base(src, alloc) { }
dchecked_vector(dchecked_vector && src)77 dchecked_vector(dchecked_vector&& src)
78 : Base(std::move(src)) { }
dchecked_vector(dchecked_vector && src,const allocator_type & alloc)79 dchecked_vector(dchecked_vector&& src, const allocator_type& alloc)
80 : Base(std::move(src), alloc) { }
81 dchecked_vector(std::initializer_list<value_type> il,
82 const allocator_type& alloc = allocator_type())
Base(il,alloc)83 : Base(il, alloc) { }
84 ~dchecked_vector() = default;
85 dchecked_vector& operator=(const dchecked_vector& src) {
86 Base::operator=(src);
87 return *this;
88 }
89 dchecked_vector& operator=(dchecked_vector&& src) {
90 Base::operator=(std::move(src));
91 return *this;
92 }
93 dchecked_vector& operator=(std::initializer_list<value_type> il) {
94 Base::operator=(il);
95 return *this;
96 }
97
98 // Iterators.
99 using Base::begin;
100 using Base::end;
101 using Base::rbegin;
102 using Base::rend;
103 using Base::cbegin;
104 using Base::cend;
105 using Base::crbegin;
106 using Base::crend;
107
108 // Capacity.
109 using Base::size;
110 using Base::max_size;
111 using Base::resize;
112 using Base::capacity;
113 using Base::empty;
114 using Base::reserve;
115 using Base::shrink_to_fit;
116
117 // Element access: inherited.
118 // Note: Deliberately not providing at().
119 using Base::data;
120
121 // Element access: subscript operator. Check index.
122 reference operator[](size_type n) {
123 DCHECK_LT(n, size());
124 return Base::operator[](n);
125 }
126 const_reference operator[](size_type n) const {
127 DCHECK_LT(n, size());
128 return Base::operator[](n);
129 }
130
131 // Element access: front(), back(). Check not empty.
front()132 reference front() { DCHECK(!empty()); return Base::front(); }
front()133 const_reference front() const { DCHECK(!empty()); return Base::front(); }
back()134 reference back() { DCHECK(!empty()); return Base::back(); }
back()135 const_reference back() const { DCHECK(!empty()); return Base::back(); }
136
137 // Modifiers: inherited.
138 using Base::assign;
139 using Base::push_back;
140 using Base::clear;
141 using Base::emplace_back;
142
143 // Modifiers: pop_back(). Check not empty.
pop_back()144 void pop_back() { DCHECK(!empty()); Base::pop_back(); }
145
146 // Modifiers: swap(). Swap only with another dchecked_vector instead of a plain vector.
swap(dchecked_vector & other)147 void swap(dchecked_vector& other) { Base::swap(other); }
148
149 // Modifiers: insert(). Check position.
insert(const_iterator position,const value_type & value)150 iterator insert(const_iterator position, const value_type& value) {
151 DCHECK(cbegin() <= position && position <= cend());
152 return Base::insert(position, value);
153 }
insert(const_iterator position,size_type n,const value_type & value)154 iterator insert(const_iterator position, size_type n, const value_type& value) {
155 DCHECK(cbegin() <= position && position <= cend());
156 return Base::insert(position, n, value);
157 }
158 template <typename InputIterator>
insert(const_iterator position,InputIterator first,InputIterator last)159 iterator insert(const_iterator position, InputIterator first, InputIterator last) {
160 DCHECK(cbegin() <= position && position <= cend());
161 return Base::insert(position, first, last);
162 }
insert(const_iterator position,value_type && value)163 iterator insert(const_iterator position, value_type&& value) {
164 DCHECK(cbegin() <= position && position <= cend());
165 return Base::insert(position, std::move(value));
166 }
insert(const_iterator position,std::initializer_list<value_type> il)167 iterator insert(const_iterator position, std::initializer_list<value_type> il) {
168 DCHECK(cbegin() <= position && position <= cend());
169 return Base::insert(position, il);
170 }
171
172 // Modifiers: erase(). Check position.
erase(const_iterator position)173 iterator erase(const_iterator position) {
174 DCHECK(cbegin() <= position && position < cend());
175 return Base::erase(position);
176 }
erase(const_iterator first,const_iterator last)177 iterator erase(const_iterator first, const_iterator last) {
178 DCHECK(cbegin() <= first && first <= cend());
179 DCHECK(first <= last && last <= cend());
180 return Base::erase(first, last);
181 }
182
183 // Modifiers: emplace(). Check position.
184 template <typename... Args>
emplace(const_iterator position,Args &&...args)185 iterator emplace(const_iterator position, Args&&... args) {
186 DCHECK(cbegin() <= position && position <= cend());
187 Base::emplace(position, std::forward(args...));
188 }
189
190 // Allocator.
191 using Base::get_allocator;
192 };
193
194 // Non-member swap(), found by argument-dependent lookup for an unqualified call.
195 template <typename T, typename Alloc>
swap(dchecked_vector<T,Alloc> & lhs,dchecked_vector<T,Alloc> & rhs)196 void swap(dchecked_vector<T, Alloc>& lhs, dchecked_vector<T, Alloc>& rhs) {
197 lhs.swap(rhs);
198 }
199
200 // Non-member relational operators.
201 template <typename T, typename Alloc>
202 bool operator==(const dchecked_vector<T, Alloc>& lhs, const dchecked_vector<T, Alloc>& rhs) {
203 return lhs.size() == rhs.size() && std::equal(lhs.begin(), lhs.end(), rhs.begin());
204 }
205 template <typename T, typename Alloc>
206 bool operator!=(const dchecked_vector<T, Alloc>& lhs, const dchecked_vector<T, Alloc>& rhs) {
207 return !(lhs == rhs);
208 }
209 template <typename T, typename Alloc>
210 bool operator<(const dchecked_vector<T, Alloc>& lhs, const dchecked_vector<T, Alloc>& rhs) {
211 return std::lexicographical_compare(lhs.begin(), lhs.end(), rhs.begin(), rhs.end());
212 }
213 template <typename T, typename Alloc>
214 bool operator<=(const dchecked_vector<T, Alloc>& lhs, const dchecked_vector<T, Alloc>& rhs) {
215 return !(rhs < lhs);
216 }
217 template <typename T, typename Alloc>
218 bool operator>(const dchecked_vector<T, Alloc>& lhs, const dchecked_vector<T, Alloc>& rhs) {
219 return rhs < lhs;
220 }
221 template <typename T, typename Alloc>
222 bool operator>=(const dchecked_vector<T, Alloc>& lhs, const dchecked_vector<T, Alloc>& rhs) {
223 return !(lhs < rhs);
224 }
225
226 } // namespace art
227
228 #endif // ART_LIBARTBASE_BASE_DCHECKED_VECTOR_H_
229