python-2.5.2/win32/include/pyarena.h
changeset 0 ae805ac0140d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/python-2.5.2/win32/include/pyarena.h	Fri Apr 03 17:19:34 2009 +0100
@@ -0,0 +1,62 @@
+/* An arena-like memory interface for the compiler.
+ */
+
+#ifndef Py_PYARENA_H
+#define Py_PYARENA_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+  typedef struct _arena PyArena;
+
+  /* PyArena_New() and PyArena_Free() create a new arena and free it,
+     respectively.  Once an arena has been created, it can be used
+     to allocate memory via PyArena_Malloc().  Pointers to PyObject can
+     also be registered with the arena via PyArena_AddPyObject(), and the
+     arena will ensure that the PyObjects stay alive at least until
+     PyArena_Free() is called.  When an arena is freed, all the memory it
+     allocated is freed, the arena releases internal references to registered
+     PyObject*, and none of its pointers are valid.
+     XXX (tim) What does "none of its pointers are valid" mean?  Does it
+     XXX mean that pointers previously obtained via PyArena_Malloc() are
+     XXX no longer valid?  (That's clearly true, but not sure that's what
+     XXX the text is trying to say.)
+
+     PyArena_New() returns an arena pointer.  On error, it
+     returns a negative number and sets an exception.
+     XXX (tim):  Not true.  On error, PyArena_New() actually returns NULL,
+     XXX and looks like it may or may not set an exception (e.g., if the
+     XXX internal PyList_New(0) returns NULL, PyArena_New() passes that on
+     XXX and an exception is set; OTOH, if the internal
+     XXX block_new(DEFAULT_BLOCK_SIZE) returns NULL, that's passed on but
+     XXX an exception is not set in that case).
+  */
+  PyAPI_FUNC(PyArena *) PyArena_New(void);
+  PyAPI_FUNC(void) PyArena_Free(PyArena *);
+
+  /* Mostly like malloc(), return the address of a block of memory spanning
+   * `size` bytes, or return NULL (without setting an exception) if enough
+   * new memory can't be obtained.  Unlike malloc(0), PyArena_Malloc() with
+   * size=0 does not guarantee to return a unique pointer (the pointer
+   * returned may equal one or more other pointers obtained from
+   * PyArena_Malloc()).
+   * Note that pointers obtained via PyArena_Malloc() must never be passed to
+   * the system free() or realloc(), or to any of Python's similar memory-
+   * management functions.  PyArena_Malloc()-obtained pointers remain valid
+   * until PyArena_Free(ar) is called, at which point all pointers obtained
+   * from the arena `ar` become invalid simultaneously.
+   */
+  PyAPI_FUNC(void *) PyArena_Malloc(PyArena *, size_t size);
+
+  /* This routine isn't a proper arena allocation routine.  It takes
+   * a PyObject* and records it so that it can be DECREFed when the
+   * arena is freed.
+   */
+  PyAPI_FUNC(int) PyArena_AddPyObject(PyArena *, PyObject *);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* !Py_PYARENA_H */