In C++, it's an error to pass a string literal to a char* function
without a const_cast(). Rather than require every C++ extension
module to put a cast around string literals, fix the API to state the
const-ness.
I focused on parts of the API where people usually pass literals:
PyArg_ParseTuple() and friends, Py_BuildValue(), PyMethodDef, the type
slots, etc. Predictably, there were a large set of functions that
needed to be fixed as a result of these changes. The most pervasive
change was to make the keyword args list passed to
PyArg_ParseTupleAndKewords() to be a const char *kwlist[].
One cast was required as a result of the changes: A type object
mallocs the memory for its tp_doc slot and later frees it.
PyTypeObject says that tp_doc is const char *; but if the type was
created by type_new(), we know it is safe to cast to char *.
* Modules/bz2module.c
(BZ2FileObject): Now the structure includes a pointer to a file object,
instead of "inheriting" one. Also, some members were copied from the
PyFileObject structure to avoid dealing with the internals of that
structure from outside fileobject.c.
(Util_GetLine,Util_DropReadAhead,Util_ReadAhead,Util_ReadAheadGetLineSkip,
BZ2File_write,BZ2File_writelines,BZ2File_init,BZ2File_dealloc,
BZ2Comp_dealloc,BZ2Decomp_dealloc):
These functions were adapted to the change above.
(BZ2File_seek,BZ2File_close): Use PyObject_CallMethod instead of
getting the function attribute locally.
(BZ2File_notsup): Removed, since it's not necessary anymore to overload
truncate(), and readinto() with dummy functions.
(BZ2File_methods): Added xreadlines() as an alias to BZ2File_getiter,
and removed truncate() and readinto().
(BZ2File_get_newlines,BZ2File_get_closed,BZ2File_get_mode,BZ2File_get_name,
BZ2File_getset):
Implemented getters for "newlines", "mode", and "name".
(BZ2File_members): Implemented "softspace" member.
(BZ2File_init): Reworked to create a file instance instead of initializing
itself as a file subclass. Also, pass "name" object untouched to the
file constructor, and use PyObject_CallFunction instead of building the
argument tuple locally.
(BZ2File_Type): Set tp_new to PyType_GenericNew, tp_members to
BZ2File_members, and tp_getset to BZ2File_getset.
(initbz2): Do not set BZ2File_Type.tp_base nor BZ2File_Type.tp_new.
* Doc/lib/libbz2.tex
Do not mention that BZ2File inherits from the file type.
The attached patch enables shared extension
modules to build cleanly under Cygwin without
moving the static initialization of certain function
pointers (i.e., ones exported from the Python
DLL core) to a module initialization function.
Additionally, this patch fixes the modules that
have been changed in the past to accommodate
Cygwin.
Neal Norwitz
Jeremy Hylton
Georg Brandl
Walter Dörwald
Gustavo Niemeyer
Skip Montanaro
Martin v. Löwis
Jason Tishler
Tim Peters