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allocator.h
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1// Copyright 2007-2010 Baptiste Lepilleur and The JsonCpp Authors
2// Distributed under MIT license, or public domain if desired and
3// recognized in your jurisdiction.
4// See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
5
6#ifndef JSON_ALLOCATOR_H_INCLUDED
7#define JSON_ALLOCATOR_H_INCLUDED
8
9#include <cstring>
10#include <memory>
11
12#pragma pack(push)
13#pragma pack()
14
15namespace Json {
16template <typename T> class SecureAllocator {
17public:
18 // Type definitions
19 using value_type = T;
20 using pointer = T*;
21 using const_pointer = const T*;
22 using reference = T&;
23 using const_reference = const T&;
24 using size_type = std::size_t;
25 using difference_type = std::ptrdiff_t;
26
31 // allocate using "global operator new"
32 return static_cast<pointer>(::operator new(n * sizeof(T)));
33 }
34
41 // memset_s is used because memset may be optimized away by the compiler
42 memset_s(p, n * sizeof(T), 0, n * sizeof(T));
43 // free using "global operator delete"
44 ::operator delete(p);
45 }
46
50 template <typename... Args> void construct(pointer p, Args&&... args) {
51 // construct using "placement new" and "perfect forwarding"
52 ::new (static_cast<void*>(p)) T(std::forward<Args>(args)...);
53 }
54
55 size_type max_size() const { return size_t(-1) / sizeof(T); }
56
57 pointer address(reference x) const { return std::addressof(x); }
58
59 const_pointer address(const_reference x) const { return std::addressof(x); }
60
64 void destroy(pointer p) {
65 // destroy using "explicit destructor"
66 p->~T();
67 }
68
69 // Boilerplate
71 template <typename U> SecureAllocator(const SecureAllocator<U>&) {}
72 template <typename U> struct rebind { using other = SecureAllocator<U>; };
73};
74
75template <typename T, typename U>
77 return true;
78}
79
80template <typename T, typename U>
82 return false;
83}
84
85} // namespace Json
86
87#pragma pack(pop)
88
89#endif // JSON_ALLOCATOR_H_INCLUDED
size_type max_size() const
Definition: allocator.h:55
const_pointer address(const_reference x) const
Definition: allocator.h:59
pointer address(reference x) const
Definition: allocator.h:57
const T & const_reference
Definition: allocator.h:23
std::ptrdiff_t difference_type
Definition: allocator.h:25
const T * const_pointer
Definition: allocator.h:21
std::size_t size_type
Definition: allocator.h:24
void destroy(pointer p)
Destroy an item in-place at pointer P.
Definition: allocator.h:64
void deallocate(pointer p, size_type n)
Release memory which was allocated for N items at pointer P.
Definition: allocator.h:40
pointer allocate(size_type n)
Allocate memory for N items using the standard allocator.
Definition: allocator.h:30
void construct(pointer p, Args &&... args)
Construct an item in-place at pointer P.
Definition: allocator.h:50
SecureAllocator(const SecureAllocator< U > &)
Definition: allocator.h:71
JSON (JavaScript Object Notation).
Definition: allocator.h:15
bool operator==(const SecureAllocator< T > &, const SecureAllocator< U > &)
Definition: allocator.h:76
bool operator!=(const SecureAllocator< T > &, const SecureAllocator< U > &)
Definition: allocator.h:81