Add two scenarios by Vladimir Marangozov that show how to use your own
allocator.
diff --git a/Include/mymalloc.h b/Include/mymalloc.h
index df3113b..e00ef24 100644
--- a/Include/mymalloc.h
+++ b/Include/mymalloc.h
@@ -95,7 +95,10 @@
The PyCore_* macros can be defined to make the interpreter use a
custom allocator. Note that they are for internal use only. Both
- the core and extension modules should use the PyMem_* API. */
+ the core and extension modules should use the PyMem_* API.
+
+ See the comment block at the end of this file for two scenarios
+ showing how to use this to use a different allocator. */
#ifndef PyCore_MALLOC_FUNC
#undef PyCore_REALLOC_FUNC
@@ -200,4 +203,43 @@
}
#endif
+/* SCENARIOS
+
+ Here are two scenarios by Vladimir Marangozov (the author of the
+ memory allocation redesign).
+
+ 1) Scenario A
+
+ Suppose you want to use a debugging malloc library that collects info on
+ where the malloc calls originate from. Assume the interface is:
+
+ d_malloc(size_t n, char* src_file, unsigned long src_line) c.s.
+
+ In this case, you would define (for example in config.h) :
+
+ #define PyCore_MALLOC_FUNC d_malloc
+ ...
+ #define PyCore_MALLOC_PROTO Py_PROTO((size_t, char *, unsigned long))
+ ...
+ #define NEED_TO_DECLARE_MALLOC_AND_FRIEND
+
+ #define PyCore_MALLOC(n) PyCore_MALLOC_FUNC((n), __FILE__, __LINE__)
+ ...
+
+ 2) Scenario B
+
+ Suppose you want to use malloc hooks (defined & initialized in a 3rd party
+ malloc library) instead of malloc functions. In this case, you would
+ define:
+
+ #define PyCore_MALLOC_FUNC (*malloc_hook)
+ ...
+ #define NEED_TO_DECLARE_MALLOC_AND_FRIEND
+
+ and ignore the previous definitions about PyCore_MALLOC_FUNC, etc.
+
+
+*/
+
+
#endif /* !Py_MYMALLOC_H */