codekingpro/portable-devtools

1#ifndef GREENLET_ALLOCATOR_HPP
2#define GREENLET_ALLOCATOR_HPP
3
4#define PY_SSIZE_T_CLEAN
5#include <Python.h>
6#include <memory>
7#include "greenlet_compiler_compat.hpp"
8#include "greenlet_cpython_compat.hpp"
9
10
11namespace greenlet
12{
13    // This allocator is stateless; all instances are identical.
14    // It can *ONLY* be used when we're sure we're holding the GIL
15    // (Python's allocators require the GIL).
16    template <class T>
17    struct PythonAllocator : public std::allocator<T> {
18
19        PythonAllocator(const PythonAllocator& UNUSED(other))
20            : std::allocator<T>()
21        {
22        }
23
24        PythonAllocator(const std::allocator<T> other)
25            : std::allocator<T>(other)
26        {}
27
28        template <class U>
29        PythonAllocator(const std::allocator<U>& other)
30            : std::allocator<T>(other)
31        {
32        }
33
34        PythonAllocator() : std::allocator<T>() {}
35
36        T* allocate(size_t number_objects, const void* UNUSED(hint)=0)
37        {
38            void* p;
39            if (number_objects == 1) {
40#ifdef Py_GIL_DISABLED
41                p = PyMem_Malloc(sizeof(T) * number_objects);
42#else
43                p = PyObject_Malloc(sizeof(T));
44#endif
45            }
46            else {
47                p = PyMem_Malloc(sizeof(T) * number_objects);
48            }
49            return static_cast<T*>(p);
50        }
51
52        void deallocate(T* t, size_t n)
53        {
54            void* p = t;
55            if (n == 1) {
56#ifdef Py_GIL_DISABLED
57                PyMem_Free(p);
58#else
59                PyObject_Free(p);
60#endif
61            }
62            else {
63                PyMem_Free(p);
64            }
65        }
66        // This member is deprecated in C++17 and removed in C++20
67        template< class U >
68        struct rebind {
69            typedef PythonAllocator<U> other;
70        };
71
72    };
73
74}
75
76#endif
77