libcxx/include/__memory_resource/synchronized_pool_resource.h

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef _LIBCPP___MEMORY_RESOURCE_SYNCHRONIZED_POOL_RESOURCE_H
  10 #define _LIBCPP___MEMORY_RESOURCE_SYNCHRONIZED_POOL_RESOURCE_H
  11
  12 #include <__config>
  13 #include <__cstddef/size_t.h>
  14 #include <__memory_resource/memory_resource.h>
  15 #include <__memory_resource/pool_options.h>
  16 #include <__memory_resource/unsynchronized_pool_resource.h>
  17 #include <__mutex/mutex.h>
  18 #include <__mutex/unique_lock.h>
  19
  20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  21 #  pragma GCC system_header
  22 #endif
  23
  24 #if _LIBCPP_STD_VER >= 17
  25
  26 _LIBCPP_BEGIN_NAMESPACE_STD
  27
  28 namespace pmr {
  29
  30 // [mem.res.pool.overview]
  31
  32 class _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI synchronized_pool_resource : public memory_resource {
  33 public:
  34   _LIBCPP_HIDE_FROM_ABI synchronized_pool_resource(const pool_options& __opts, memory_resource* __upstream)
  35       : __unsync_(__opts, __upstream) {}
  36
  37   _LIBCPP_HIDE_FROM_ABI synchronized_pool_resource()
  38       : synchronized_pool_resource(pool_options(), get_default_resource()) {}
  39
  40   _LIBCPP_HIDE_FROM_ABI explicit synchronized_pool_resource(memory_resource* __upstream)
  41       : synchronized_pool_resource(pool_options(), __upstream) {}
  42
  43   _LIBCPP_HIDE_FROM_ABI explicit synchronized_pool_resource(const pool_options& __opts)
  44       : synchronized_pool_resource(__opts, get_default_resource()) {}
  45
  46   synchronized_pool_resource(const synchronized_pool_resource&) = delete;
  47
  48   _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~synchronized_pool_resource() override = default;
  49
  50   synchronized_pool_resource& operator=(const synchronized_pool_resource&) = delete;
  51
  52   _LIBCPP_HIDE_FROM_ABI void release() {
  53 #  if _LIBCPP_HAS_THREADS
  54     unique_lock<mutex> __lk(__mut_);
  55 #  endif
  56     __unsync_.release();
  57   }
  58
  59   _LIBCPP_HIDE_FROM_ABI memory_resource* upstream_resource() const { return __unsync_.upstream_resource(); }
  60
  61   _LIBCPP_HIDE_FROM_ABI pool_options options() const { return __unsync_.options(); }
  62
  63 protected:
  64   _LIBCPP_HIDE_FROM_ABI_VIRTUAL void* do_allocate(size_t __bytes, size_t __align) override {
  65 #  if _LIBCPP_HAS_THREADS
  66     unique_lock<mutex> __lk(__mut_);
  67 #  endif
  68     return __unsync_.allocate(__bytes, __align);
  69   }
  70
  71   _LIBCPP_HIDE_FROM_ABI_VIRTUAL void do_deallocate(void* __p, size_t __bytes, size_t __align) override {
  72 #  if _LIBCPP_HAS_THREADS
  73     unique_lock<mutex> __lk(__mut_);
  74 #  endif
  75     return __unsync_.deallocate(__p, __bytes, __align);
  76   }
  77
  78   bool do_is_equal(const memory_resource& __other) const noexcept override; // key function
  79
  80 private:
  81 #  if _LIBCPP_HAS_THREADS
  82   mutex __mut_;
  83 #  endif
  84   unsynchronized_pool_resource __unsync_;
  85 };
  86
  87 } // namespace pmr
  88
  89 _LIBCPP_END_NAMESPACE_STD
  90
  91 #endif // _LIBCPP_STD_VER >= 17
  92
  93 #endif // _LIBCPP___MEMORY_RESOURCE_SYNCHRONIZED_POOL_RESOURCE_H