[pypy-svn] r72862 - pypy/branch/cpython-extension/pypy/module/cpyext

[afa at codespeak.net]

Author: afa
Date: Thu Mar 25 23:46:25 2010
New Revision: 72862

Added:
   pypy/branch/cpython-extension/pypy/module/cpyext/c-api.txt   (contents, props changed)
Modified:
   pypy/branch/cpython-extension/pypy/module/cpyext/TODO
Log:
Update TODO, start a technical documentation


Modified: pypy/branch/cpython-extension/pypy/module/cpyext/TODO
==============================================================================
--- pypy/branch/cpython-extension/pypy/module/cpyext/TODO	(original)
+++ pypy/branch/cpython-extension/pypy/module/cpyext/TODO	Thu Mar 25 23:46:25 2010
@@ -1,52 +1,20 @@
- - Implement C API.
  - Complete the PyTypeObject initialization code.
+
  - Use a WeakKeyDictionary to count how often a PyObject is allocated for
    a given wrapped object and use this to assess whether optimizations are
    useful
+
  - lltype.free in PyObject_Del() sometimes raise an exception (but all
-   tests pass)
+   tests pass). FIXED?
    - Reported by Amaury
    - Alexander cannot reproduce it
 
+ - replace @cpython_api(external=False) by another explicit name: all
+   it does is a lltype function pointer, no C code involved.
 
-PyStringObject support
-======================
-
-The problem
------------
-
-PyString_AsString() should return a (non-movable) pointer
-to the underlying buffer, whereas pypy strings are movable.  C code
-may temporarily store this address and use it, as long as it owns a
-reference to the PyObject.  There is no "release" function to specify
-that the pointer is not needed any more.
-
-Note that the pointer may be used to fill the initial value of
-string. This is valid only when the string was just allocated, and is
-not used elsewhere.
-
-Proposed solution
------------------
-
-Our emulation of the PyStringObject contains an additional member: a
-pointer to a char buffer; it may be NULL.
-
-- A string allocated by pypy will be converted into a PyStringObject
-  with a NULL buffer.  When PyString_AsString() is called, memory is
-  allocated (with flavor='raw') and content is copied.
-
-- A string allocated with PyString_FromStringAndSize(NULL, size) will
-  allocate a buffer with the specified size, but the reference won't
-  be stored in the global map py_objects_r2w; there won't be a
-  corresponding object in pypy.  When from_ref() or Py_INCREF() is
-  called, the pypy string is created, and added in py_objects_r2w.
-  The buffer is then supposed to be immutable.
-
-- _PyString_Resize works only on not-yet-pypy'd strings, and returns a
-  similar object.
+ - refactor management of py_objects_r2w and py_objects_w2r, this can
+   probably be expressed in terms of _PyObject_GC_TRACK macros.
 
-- PyString_Size don't need to force the object. (in this case, another
-  "size" member is needed)
+ - Use the standard CPython attribute names: ob_type, ob_refcnt.
 
-- There could be an (expensive!) check in from_ref() that the buffer
-  still corresponds to the pypy gc-managed string.
+ - ob_type should be a PyTypeObject.

Added: pypy/branch/cpython-extension/pypy/module/cpyext/c-api.txt
==============================================================================
--- (empty file)
+++ pypy/branch/cpython-extension/pypy/module/cpyext/c-api.txt	Thu Mar 25 23:46:25 2010
@@ -0,0 +1,51 @@
+Reference Count
+===============
+
+XXX
+
+Borrowed References
+===================
+
+XXX
+
+PyStringObject support
+======================
+
+The problem
+-----------
+
+PyString_AsString() returns a (non-movable) pointer to the underlying
+buffer, whereas pypy strings are movable.  C code may temporarily
+store this address and use it, as long as it owns a reference to the
+PyObject.  There is no "release" function to specify that the pointer
+is not needed any more.
+
+Note that the pointer may be used to fill the initial value of
+string. This is valid only when the string was just allocated, and is
+not used elsewhere.
+
+Proposed solution
+-----------------
+
+Our emulation of the PyStringObject contains an additional member: a
+pointer to a char buffer; it may be NULL.
+
+- A string allocated by pypy will be converted into a PyStringObject
+  with a NULL buffer.  When PyString_AsString() is called, memory is
+  allocated (with flavor='raw') and content is copied.
+
+- A string allocated with PyString_FromStringAndSize(NULL, size) will
+  allocate a buffer with the specified size, but the reference won't
+  be stored in the global map py_objects_r2w; there won't be a
+  corresponding object in pypy.  When from_ref() or Py_INCREF() is
+  called, the pypy string is created, and added in py_objects_r2w.
+  The buffer is then supposed to be immutable.
+
+- _PyString_Resize works only on not-yet-pypy'd strings, and returns a
+  similar object.
+
+- PyString_Size don't need to force the object. (in this case, another
+  "size" member is needed)
+
+- There could be an (expensive!) check in from_ref() that the buffer
+  still corresponds to the pypy gc-managed string.