You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
108 lines
3.9 KiB
108 lines
3.9 KiB
/* The PyMem_ family: low-level memory allocation interfaces. |
|
See objimpl.h for the PyObject_ memory family. |
|
*/ |
|
|
|
#ifndef Py_PYMEM_H |
|
#define Py_PYMEM_H |
|
|
|
#include "pyport.h" |
|
|
|
#ifdef __cplusplus |
|
extern "C" { |
|
#endif |
|
|
|
/* BEWARE: |
|
|
|
Each interface exports both functions and macros. Extension modules should |
|
use the functions, to ensure binary compatibility across Python versions. |
|
Because the Python implementation is free to change internal details, and |
|
the macros may (or may not) expose details for speed, if you do use the |
|
macros you must recompile your extensions with each Python release. |
|
|
|
Never mix calls to PyMem_ with calls to the platform malloc/realloc/ |
|
calloc/free. For example, on Windows different DLLs may end up using |
|
different heaps, and if you use PyMem_Malloc you'll get the memory from the |
|
heap used by the Python DLL; it could be a disaster if you free()'ed that |
|
directly in your own extension. Using PyMem_Free instead ensures Python |
|
can return the memory to the proper heap. As another example, in |
|
PYMALLOC_DEBUG mode, Python wraps all calls to all PyMem_ and PyObject_ |
|
memory functions in special debugging wrappers that add additional |
|
debugging info to dynamic memory blocks. The system routines have no idea |
|
what to do with that stuff, and the Python wrappers have no idea what to do |
|
with raw blocks obtained directly by the system routines then. |
|
*/ |
|
|
|
/* |
|
* Raw memory interface |
|
* ==================== |
|
*/ |
|
|
|
/* Functions |
|
|
|
Functions supplying platform-independent semantics for malloc/realloc/ |
|
free. These functions make sure that allocating 0 bytes returns a distinct |
|
non-NULL pointer (whenever possible -- if we're flat out of memory, NULL |
|
may be returned), even if the platform malloc and realloc don't. |
|
Returned pointers must be checked for NULL explicitly. No action is |
|
performed on failure (no exception is set, no warning is printed, etc). |
|
*/ |
|
|
|
PyAPI_FUNC(void *) PyMem_Malloc(size_t); |
|
PyAPI_FUNC(void *) PyMem_Realloc(void *, size_t); |
|
PyAPI_FUNC(void) PyMem_Free(void *); |
|
|
|
/* Starting from Python 1.6, the wrappers Py_{Malloc,Realloc,Free} are |
|
no longer supported. They used to call PyErr_NoMemory() on failure. */ |
|
|
|
/* Macros. */ |
|
#ifdef PYMALLOC_DEBUG |
|
/* Redirect all memory operations to Python's debugging allocator. */ |
|
#define PyMem_MALLOC PyObject_MALLOC |
|
#define PyMem_REALLOC PyObject_REALLOC |
|
|
|
#else /* ! PYMALLOC_DEBUG */ |
|
|
|
/* PyMem_MALLOC(0) means malloc(1). Some systems would return NULL |
|
for malloc(0), which would be treated as an error. Some platforms |
|
would return a pointer with no memory behind it, which would break |
|
pymalloc. To solve these problems, allocate an extra byte. */ |
|
#define PyMem_MALLOC(n) malloc((n) ? (n) : 1) |
|
#define PyMem_REALLOC(p, n) realloc((p), (n) ? (n) : 1) |
|
|
|
#endif /* PYMALLOC_DEBUG */ |
|
|
|
/* In order to avoid breaking old code mixing PyObject_{New, NEW} with |
|
PyMem_{Del, DEL} and PyMem_{Free, FREE}, the PyMem "release memory" |
|
functions have to be redirected to the object deallocator. */ |
|
#define PyMem_FREE PyObject_FREE |
|
|
|
/* |
|
* Type-oriented memory interface |
|
* ============================== |
|
* |
|
* These are carried along for historical reasons. There's rarely a good |
|
* reason to use them anymore (you can just as easily do the multiply and |
|
* cast yourself). |
|
*/ |
|
|
|
#define PyMem_New(type, n) \ |
|
( (type *) PyMem_Malloc((n) * sizeof(type)) ) |
|
#define PyMem_NEW(type, n) \ |
|
( (type *) PyMem_MALLOC((n) * sizeof(type)) ) |
|
|
|
#define PyMem_Resize(p, type, n) \ |
|
( (p) = (type *) PyMem_Realloc((p), (n) * sizeof(type)) ) |
|
#define PyMem_RESIZE(p, type, n) \ |
|
( (p) = (type *) PyMem_REALLOC((p), (n) * sizeof(type)) ) |
|
|
|
/* In order to avoid breaking old code mixing PyObject_{New, NEW} with |
|
PyMem_{Del, DEL} and PyMem_{Free, FREE}, the PyMem "release memory" |
|
functions have to be redirected to the object deallocator. */ |
|
#define PyMem_Del PyObject_Free |
|
#define PyMem_DEL PyObject_FREE |
|
|
|
#ifdef __cplusplus |
|
} |
|
#endif |
|
|
|
#endif /* !Py_PYMEM_H */
|
|
|