1 //////////////////////////////////////////////////////////////////////////////
2 //
3 // (C) Copyright Ion Gaztanaga 2015-2015. Distributed under the Boost
4 // Software License, Version 1.0. (See accompanying file
5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 //
7 // See http://www.boost.org/libs/container for documentation.
8 //
9 //////////////////////////////////////////////////////////////////////////////
10 
11 #define BOOST_CONTAINER_SOURCE
12 #include <boost/container/pmr/memory_resource.hpp>
13 #include <boost/container/pmr/global_resource.hpp>
14 #include <boost/core/no_exceptions_support.hpp>
15 #include <boost/container/throw_exception.hpp>
16 #include <boost/container/detail/dlmalloc.hpp>  //For global lock
17 #include <boost/container/detail/singleton.hpp>
18 
19 #include <cstddef>
20 #include <new>
21 
22 namespace boost {
23 namespace container {
24 namespace pmr {
25 
26 class new_delete_resource_imp
27    : public memory_resource
28 {
29    public:
30 
~new_delete_resource_imp()31    ~new_delete_resource_imp() BOOST_OVERRIDE
32    {}
33 
do_allocate(std::size_t bytes,std::size_t alignment)34    void* do_allocate(std::size_t bytes, std::size_t alignment) BOOST_OVERRIDE
35    {  (void)bytes; (void)alignment; return new char[bytes];  }
36 
do_deallocate(void * p,std::size_t bytes,std::size_t alignment)37    void do_deallocate(void* p, std::size_t bytes, std::size_t alignment) BOOST_OVERRIDE
38    {  (void)bytes; (void)alignment; delete[]((char*)p);  }
39 
do_is_equal(const memory_resource & other) const40    bool do_is_equal(const memory_resource& other) const BOOST_NOEXCEPT BOOST_OVERRIDE
41    {  return &other == this;   }
42 };
43 
44 struct null_memory_resource_imp
45    : public memory_resource
46 {
47    public:
48 
~null_memory_resource_impboost::container::pmr::null_memory_resource_imp49    ~null_memory_resource_imp() BOOST_OVERRIDE
50    {}
51 
do_allocateboost::container::pmr::null_memory_resource_imp52    void* do_allocate(std::size_t bytes, std::size_t alignment) BOOST_OVERRIDE
53    {
54       (void)bytes; (void)alignment;
55       #if defined(BOOST_CONTAINER_USER_DEFINED_THROW_CALLBACKS) || defined(BOOST_NO_EXCEPTIONS)
56       throw_bad_alloc();
57       #else
58       throw std::bad_alloc();
59       #endif
60 
61       return 0;
62    }
63 
do_deallocateboost::container::pmr::null_memory_resource_imp64    void do_deallocate(void* p, std::size_t bytes, std::size_t alignment) BOOST_OVERRIDE
65    {  (void)p;  (void)bytes; (void)alignment;  }
66 
do_is_equalboost::container::pmr::null_memory_resource_imp67    bool do_is_equal(const memory_resource& other) const BOOST_NOEXCEPT BOOST_OVERRIDE
68    {  return &other == this;   }
69 };
70 
new_delete_resource()71 BOOST_CONTAINER_DECL memory_resource* new_delete_resource() BOOST_NOEXCEPT
72 {
73    return &boost::container::dtl::singleton_default<new_delete_resource_imp>::instance();
74 }
75 
null_memory_resource()76 BOOST_CONTAINER_DECL memory_resource* null_memory_resource() BOOST_NOEXCEPT
77 {
78    return &boost::container::dtl::singleton_default<null_memory_resource_imp>::instance();
79 }
80 
81 static memory_resource *default_memory_resource =
82    &boost::container::dtl::singleton_default<new_delete_resource_imp>::instance();
83 
set_default_resource(memory_resource * r)84 BOOST_CONTAINER_DECL memory_resource* set_default_resource(memory_resource* r) BOOST_NOEXCEPT
85 {
86    //TO-DO: synchronizes-with part using atomics
87    if(dlmalloc_global_sync_lock()){
88       memory_resource *previous = default_memory_resource;
89       if(!previous){
90          //function called before main, default_memory_resource is not initialized yet
91          previous = new_delete_resource();
92       }
93       default_memory_resource = r ? r : new_delete_resource();
94       dlmalloc_global_sync_unlock();
95       return previous;
96    }
97    else{
98       return new_delete_resource();
99    }
100 }
101 
get_default_resource()102 BOOST_CONTAINER_DECL memory_resource* get_default_resource() BOOST_NOEXCEPT
103 {
104    //TO-DO: synchronizes-with part using atomics
105    if(dlmalloc_global_sync_lock()){
106       memory_resource *current = default_memory_resource;
107       if(!current){
108          //function called before main, default_memory_resource is not initialized yet
109          current = new_delete_resource();
110       }
111       dlmalloc_global_sync_unlock();
112       return current;
113    }
114    else{
115       return new_delete_resource();
116    }
117 }
118 
119 }  //namespace pmr {
120 }  //namespace container {
121 }  //namespace boost {
122