gh-85283: Add PyMem_RawMalloc() to the limited C API (#108570)

Add PyMem_RawMalloc(), PyMem_RawCalloc(), PyMem_RawRealloc() and
PyMem_RawFree() to the limited C API.

These functions were added by Python 3.4 and are needed to port
stdlib extensions to the limited C API, like grp and pwd.

Co-authored-by: Erlend E. Aasland <erlend@python.org>

Doc/data/stable_abi.dat

@@ -388,6 +388,10 @@ function,PyMapping_Values,3.2,,
 function,PyMem_Calloc,3.7,,
 function,PyMem_Free,3.2,,
 function,PyMem_Malloc,3.2,,
+function,PyMem_RawCalloc,3.13,,
+function,PyMem_RawFree,3.13,,
+function,PyMem_RawMalloc,3.13,,
+function,PyMem_RawRealloc,3.13,,
 function,PyMem_Realloc,3.2,,
 type,PyMemberDef,3.2,,full-abi
 var,PyMemberDescr_Type,3.2,,

Doc/whatsnew/3.13.rst

@@ -1053,6 +1053,11 @@ New Features
   parameter names.
   (Contributed by Serhiy Storchaka in :gh:`110815`.)
 
+* Add :c:func:`PyMem_RawMalloc`, :c:func:`PyMem_RawCalloc`,
+  :c:func:`PyMem_RawRealloc` and :c:func:`PyMem_RawFree` to the limited C API
+  (version 3.13).
+  (Contributed by Victor Stinner in :gh:`85283`.)
+
 Porting to Python 3.13
 ----------------------
 

Include/cpython/pymem.h

@@ -2,12 +2,6 @@
 #  error "this header file must not be included directly"
 #endif
 
-PyAPI_FUNC(void *) PyMem_RawMalloc(size_t size);
-PyAPI_FUNC(void *) PyMem_RawCalloc(size_t nelem, size_t elsize);
-PyAPI_FUNC(void *) PyMem_RawRealloc(void *ptr, size_t new_size);
-PyAPI_FUNC(void) PyMem_RawFree(void *ptr);
-
-
 typedef enum {
     /* PyMem_RawMalloc(), PyMem_RawRealloc() and PyMem_RawFree() */
     PYMEM_DOMAIN_RAW,

Include/pymem.h

@@ -87,6 +87,17 @@ PyAPI_FUNC(void) PyMem_Free(void *ptr);
 #define PyMem_DEL(p)              PyMem_Free((p))
 
 
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030d0000
+// Memory allocator which doesn't require the GIL to be held.
+// Usually, it's just a thin wrapper to functions of the standard C library:
+// malloc(), calloc(), realloc() and free(). The difference is that
+// tracemalloc can track these memory allocations.
+PyAPI_FUNC(void *) PyMem_RawMalloc(size_t size);
+PyAPI_FUNC(void *) PyMem_RawCalloc(size_t nelem, size_t elsize);
+PyAPI_FUNC(void *) PyMem_RawRealloc(void *ptr, size_t new_size);
+PyAPI_FUNC(void) PyMem_RawFree(void *ptr);
+#endif
+
 #ifndef Py_LIMITED_API
 #  define Py_CPYTHON_PYMEM_H
 #  include "cpython/pymem.h"

Lib/test/test_stable_abi_ctypes.py

@@ -418,6 +418,10 @@ SYMBOL_NAMES = (
     "PyMem_Calloc",
     "PyMem_Free",
     "PyMem_Malloc",
+    "PyMem_RawCalloc",
+    "PyMem_RawFree",
+    "PyMem_RawMalloc",
+    "PyMem_RawRealloc",
     "PyMem_Realloc",
     "PyMemberDescr_Type",
     "PyMember_GetOne",

Misc/NEWS.d/next/C API/2023-08-28-17-34-10.gh-issue-85283.f1zXcc.rst

@@ -0,0 +1,3 @@
+Add :c:func:`PyMem_RawMalloc`, :c:func:`PyMem_RawCalloc`,
+:c:func:`PyMem_RawRealloc` and :c:func:`PyMem_RawFree` to the limited C API.
+Patch by Victor Stinner.

Misc/stable_abi.toml

@@ -2466,3 +2466,11 @@
     added = '3.13'
 [function.PyUnicode_EqualToUTF8AndSize]
     added = '3.13'
+[function.PyMem_RawMalloc]
+    added = '3.13'
+[function.PyMem_RawCalloc]
+    added = '3.13'
+[function.PyMem_RawRealloc]
+    added = '3.13'
+[function.PyMem_RawFree]
+    added = '3.13'

PC/python3dll.c

@@ -373,6 +373,10 @@ EXPORT_FUNC(PyMarshal_WriteObjectToString)
 EXPORT_FUNC(PyMem_Calloc)
 EXPORT_FUNC(PyMem_Free)
 EXPORT_FUNC(PyMem_Malloc)
+EXPORT_FUNC(PyMem_RawCalloc)
+EXPORT_FUNC(PyMem_RawFree)
+EXPORT_FUNC(PyMem_RawMalloc)
+EXPORT_FUNC(PyMem_RawRealloc)
 EXPORT_FUNC(PyMem_Realloc)
 EXPORT_FUNC(PyMember_GetOne)
 EXPORT_FUNC(PyMember_SetOne)