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// Copyright 2007-2010 Baptiste Lepilleur and The JsonCpp Authors
// Distributed under MIT license, or public domain if desired and
// recognized in your jurisdiction.
// See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
#ifndef JSON_ALLOCATOR_H_INCLUDED
#define JSON_ALLOCATOR_H_INCLUDED
#include <cstring>
#include <memory>
#pragma pack(push, 8)
namespace Json {
template <typename T> class SecureAllocator {
public:
// Type definitions
using value_type = T;
using pointer = T*;
using const_pointer = const T*;
using reference = T&;
using const_reference = const T&;
using size_type = std::size_t;
using difference_type = std::ptrdiff_t;
/**
* Allocate memory for N items using the standard allocator.
*/
pointer allocate(size_type n) {
// allocate using "global operator new"
return static_cast<pointer>(::operator new(n * sizeof(T)));
}
/**
* Release memory which was allocated for N items at pointer P.
*
* The memory block is filled with zeroes before being released.
* The pointer argument is tagged as "volatile" to prevent the
* compiler optimizing out this critical step.
*/
void deallocate(volatile pointer p, size_type n) {
std::memset(p, 0, n * sizeof(T));
// free using "global operator delete"
::operator delete(p);
}
/**
* Construct an item in-place at pointer P.
*/
template <typename... Args> void construct(pointer p, Args&&... args) {
// construct using "placement new" and "perfect forwarding"
::new (static_cast<void*>(p)) T(std::forward<Args>(args)...);
}
size_type max_size() const { return size_t(-1) / sizeof(T); }
pointer address(reference x) const { return std::addressof(x); }
const_pointer address(const_reference x) const { return std::addressof(x); }
/**
* Destroy an item in-place at pointer P.
*/
void destroy(pointer p) {
// destroy using "explicit destructor"
p->~T();
}
// Boilerplate
SecureAllocator() {}
template <typename U> SecureAllocator(const SecureAllocator<U>&) {}
template <typename U> struct rebind { using other = SecureAllocator<U>; };
};
template <typename T, typename U>
bool operator==(const SecureAllocator<T>&, const SecureAllocator<U>&) {
return true;
}
template <typename T, typename U>
bool operator!=(const SecureAllocator<T>&, const SecureAllocator<U>&) {
return false;
}
} // namespace Json
#pragma pack(pop)
#endif // JSON_ALLOCATOR_H_INCLUDED