| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| #ifndef PALLOC_ALLOCATOR_H |
| #define PALLOC_ALLOCATOR_H |
| |
| // these extern declarations are to avoid including postgres.h in C++ code |
| extern "C" { |
| extern void *palloc(unsigned long long size); |
| extern void pfree(void *pointer); |
| } |
| |
| #include <new> |
| #include <utility> |
| |
| template <class T> class palloc_allocator { |
| public: |
| typedef T value_type; |
| typedef value_type* pointer; |
| typedef const value_type* const_pointer; |
| typedef value_type& reference; |
| typedef const value_type& const_reference; |
| typedef std::size_t size_type; |
| typedef std::ptrdiff_t difference_type; |
| |
| template <class U> |
| struct rebind { typedef palloc_allocator<U> other; }; |
| |
| palloc_allocator() = default; |
| template <class U> |
| palloc_allocator(const palloc_allocator<U>&) {} |
| |
| pointer address(reference x) const { return &x; } |
| const_pointer address(const_reference x) const { |
| return &x; |
| } |
| |
| pointer allocate(size_type n, const_pointer = 0) { |
| void* p = palloc(n * sizeof(T)); |
| if (!p) throw std::bad_alloc(); |
| return static_cast<pointer>(p); |
| } |
| |
| void deallocate(pointer p, size_type) { if (p) pfree(p); } |
| |
| size_type max_size() const { |
| return static_cast<size_type>(-1) / sizeof(T); |
| } |
| |
| template<typename... Args> |
| void construct(pointer p, Args&&... args) { |
| new(p) value_type(std::forward<Args>(args)...); |
| } |
| void destroy(pointer p) { p->~value_type(); } |
| }; |
| |
| template<> class palloc_allocator<void> { |
| public: |
| typedef void value_type; |
| typedef void* pointer; |
| typedef const void* const_pointer; |
| |
| template <class U> |
| struct rebind { typedef palloc_allocator<U> other; }; |
| }; |
| |
| |
| template <class T> |
| inline bool operator==(const palloc_allocator<T>&, const palloc_allocator<T>&) { |
| return true; |
| } |
| |
| template <class T> |
| inline bool operator!=(const palloc_allocator<T>&, const palloc_allocator<T>&) { |
| return false; |
| } |
| |
| #endif |