1 /* The idea of this file is that you bundle it with your extension, 2 #include it, program to Python 2.3's memory API and have your 3 extension build with any version of Python from 1.5.2 through to 4 2.3 (and hopefully beyond). */ 5 6 #ifndef Py_PYMEMCOMPAT_H 7 #define Py_PYMEMCOMPAT_H 8 9 #include "Python.h" 10 11 /* There are three "families" of memory API: the "raw memory", "object 12 memory" and "object" families. (This is ignoring the matter of the 13 cycle collector, about which more is said below). 14 15 Raw Memory: 16 17 PyMem_Malloc, PyMem_Realloc, PyMem_Free 18 19 Object Memory: 20 21 PyObject_Malloc, PyObject_Realloc, PyObject_Free 22 23 Object: 24 25 PyObject_New, PyObject_NewVar, PyObject_Del 26 27 The raw memory and object memory allocators both mimic the 28 malloc/realloc/free interface from ANSI C, but the object memory 29 allocator can (and, since 2.3, does by default) use a different 30 allocation strategy biased towards lots of "small" allocations. 31 32 The object family is used for allocating Python objects, and the 33 initializers take care of some basic initialization (setting the 34 refcount to 1 and filling out the ob_type field) as well as having 35 a somewhat different interface. 36 37 Do not mix the families! E.g. do not allocate memory with 38 PyMem_Malloc and free it with PyObject_Free. You may get away with 39 it quite a lot of the time, but there *are* scenarios where this 40 will break. You Have Been Warned. 41 42 Also, in many versions of Python there are an insane amount of 43 memory interfaces to choose from. Use the ones described above. */ 44 45 #if PY_VERSION_HEX < 0x01060000 46 /* raw memory interface already present */ 47 48 /* there is no object memory interface in 1.5.2 */ 49 #define PyObject_Malloc PyMem_Malloc 50 #define PyObject_Realloc PyMem_Realloc 51 #define PyObject_Free PyMem_Free 52 53 /* the object interface is there, but the names have changed */ 54 #define PyObject_New PyObject_NEW 55 #define PyObject_NewVar PyObject_NEW_VAR 56 #define PyObject_Del PyMem_Free 57 #endif 58 59 /* If your object is a container you probably want to support the 60 cycle collector, which was new in Python 2.0. 61 62 Unfortunately, the interface to the collector that was present in 63 Python 2.0 and 2.1 proved to be tricky to use, and so changed in 64 2.2 -- in a way that can't easily be papered over with macros. 65 66 This file contains macros that let you program to the 2.2 GC API. 67 Your module will compile against any Python since version 1.5.2, 68 but the type will only participate in the GC in versions 2.2 and 69 up. Some work is still necessary on your part to only fill out the 70 tp_traverse and tp_clear fields when they exist and set tp_flags 71 appropriately. 72 73 It is possible to support both the 2.0 and 2.2 GC APIs, but it's 74 not pretty and this comment block is too narrow to contain a 75 description of what's required... */ 76 77 #if PY_VERSION_HEX < 0x020200B1 78 #define PyObject_GC_New PyObject_New 79 #define PyObject_GC_NewVar PyObject_NewVar 80 #define PyObject_GC_Del PyObject_Del 81 #define PyObject_GC_Track(op) 82 #define PyObject_GC_UnTrack(op) 83 #endif 84 85 #endif /* !Py_PYMEMCOMPAT_H */ 86
