[Python-3000-checkins] r63981 - in python/branches/py3k: Lib/ctypes/__init__.py Lib/ctypes/test/test_errno.py Modules/_ctypes/_ctypes.c Modules/_ctypes/callbacks.c Modules/_ctypes/callproc.c Modules/_ctypes/ctypes.h
thomas.heller
python-3000-checkins at python.org
Fri Jun 6 11:31:41 CEST 2008
Author: thomas.heller
Date: Fri Jun 6 11:31:40 2008
New Revision: 63981
Log:
Merged revisions 63977 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r63977 | thomas.heller | 2008-06-06 10:33:46 +0200 (Fri, 06 Jun 2008) | 31 lines
Issue #1798: Add ctypes calling convention that allows safe access of errno.
ctypes maintains thread-local storage that has space for two error
numbers: private copies of the system 'errno' value and, on Windows,
the system error code accessed by the GetLastError() and
SetLastError() api functions.
Foreign functions created with CDLL(..., use_errno=True), when called,
swap the system 'errno' value with the private copy just before the
actual function call, and swapped again immediately afterwards. The
'use_errno' parameter defaults to False, in this case 'ctypes_errno'
is not touched.
On Windows, foreign functions created with CDLL(...,
use_last_error=True) or WinDLL(..., use_last_error=True) swap the
system LastError value with the ctypes private copy.
The values are also swapped immeditately before and after ctypes
callback functions are called, if the callbacks are constructed using
the new optional use_errno parameter set to True: CFUNCTYPE(...,
use_errno=TRUE) or WINFUNCTYPE(..., use_errno=True).
New ctypes functions are provided to access the ctypes private copies
from Python:
- ctypes.set_errno(value) and ctypes.set_last_error(value) store
'value' in the private copy and returns the previous value.
- ctypes.get_errno() and ctypes.get_last_error() returns the current
ctypes private copies value.
........
Added:
python/branches/py3k/Lib/ctypes/test/test_errno.py
- copied unchanged from r63977, /python/trunk/Lib/ctypes/test/test_errno.py
Modified:
python/branches/py3k/ (props changed)
python/branches/py3k/Lib/ctypes/__init__.py
python/branches/py3k/Modules/_ctypes/_ctypes.c
python/branches/py3k/Modules/_ctypes/callbacks.c
python/branches/py3k/Modules/_ctypes/callproc.c
python/branches/py3k/Modules/_ctypes/ctypes.h
Modified: python/branches/py3k/Lib/ctypes/__init__.py
==============================================================================
--- python/branches/py3k/Lib/ctypes/__init__.py (original)
+++ python/branches/py3k/Lib/ctypes/__init__.py Fri Jun 6 11:31:40 2008
@@ -30,7 +30,9 @@
DEFAULT_MODE = RTLD_GLOBAL
from _ctypes import FUNCFLAG_CDECL as _FUNCFLAG_CDECL, \
- FUNCFLAG_PYTHONAPI as _FUNCFLAG_PYTHONAPI
+ FUNCFLAG_PYTHONAPI as _FUNCFLAG_PYTHONAPI, \
+ FUNCFLAG_USE_ERRNO as _FUNCFLAG_USE_ERRNO, \
+ FUNCFLAG_USE_LASTERROR as _FUNCFLAG_USE_LASTERROR
"""
WINOLEAPI -> HRESULT
@@ -70,8 +72,9 @@
return create_string_buffer(init, size)
_c_functype_cache = {}
-def CFUNCTYPE(restype, *argtypes):
- """CFUNCTYPE(restype, *argtypes) -> function prototype.
+def CFUNCTYPE(restype, *argtypes, **kw):
+ """CFUNCTYPE(restype, *argtypes,
+ use_errno=False, use_last_error=False) -> function prototype.
restype: the result type
argtypes: a sequence specifying the argument types
@@ -85,14 +88,21 @@
prototype((ordinal number, dll object)[, paramflags]) -> foreign function exported by ordinal
prototype((function name, dll object)[, paramflags]) -> foreign function exported by name
"""
+ flags = _FUNCFLAG_CDECL
+ if kw.pop("use_errno", False):
+ flags |= _FUNCFLAG_USE_ERRNO
+ if kw.pop("use_last_error", False):
+ flags |= _FUNCFLAG_USE_LASTERROR
+ if kw:
+ raise ValueError("unexpected keyword argument(s) %s" % kw.keys())
try:
- return _c_functype_cache[(restype, argtypes)]
+ return _c_functype_cache[(restype, argtypes, flags)]
except KeyError:
class CFunctionType(_CFuncPtr):
_argtypes_ = argtypes
_restype_ = restype
- _flags_ = _FUNCFLAG_CDECL
- _c_functype_cache[(restype, argtypes)] = CFunctionType
+ _flags_ = flags
+ _c_functype_cache[(restype, argtypes, flags)] = CFunctionType
return CFunctionType
if _os.name in ("nt", "ce"):
@@ -103,16 +113,23 @@
_FUNCFLAG_STDCALL = _FUNCFLAG_CDECL
_win_functype_cache = {}
- def WINFUNCTYPE(restype, *argtypes):
+ def WINFUNCTYPE(restype, *argtypes, **kw):
# docstring set later (very similar to CFUNCTYPE.__doc__)
+ flags = _FUNCFLAG_STDCALL
+ if kw.pop("use_errno", False):
+ flags |= _FUNCFLAG_USE_ERRNO
+ if kw.pop("use_last_error", False):
+ flags |= _FUNCFLAG_USE_LASTERROR
+ if kw:
+ raise ValueError("unexpected keyword argument(s) %s" % kw.keys())
try:
- return _win_functype_cache[(restype, argtypes)]
+ return _win_functype_cache[(restype, argtypes, flags)]
except KeyError:
class WinFunctionType(_CFuncPtr):
_argtypes_ = argtypes
_restype_ = restype
- _flags_ = _FUNCFLAG_STDCALL
- _win_functype_cache[(restype, argtypes)] = WinFunctionType
+ _flags_ = flags
+ _win_functype_cache[(restype, argtypes, flags)] = WinFunctionType
return WinFunctionType
if WINFUNCTYPE.__doc__:
WINFUNCTYPE.__doc__ = CFUNCTYPE.__doc__.replace("CFUNCTYPE", "WINFUNCTYPE")
@@ -121,6 +138,7 @@
from _ctypes import dlopen as _dlopen
from _ctypes import sizeof, byref, addressof, alignment, resize
+from _ctypes import get_errno, set_errno
from _ctypes import _SimpleCData
def _check_size(typ, typecode=None):
@@ -310,12 +328,24 @@
Calling the functions releases the Python GIL during the call and
reacquires it afterwards.
"""
- class _FuncPtr(_CFuncPtr):
- _flags_ = _FUNCFLAG_CDECL
- _restype_ = c_int # default, can be overridden in instances
+ _func_flags_ = _FUNCFLAG_CDECL
+ _func_restype_ = c_int
- def __init__(self, name, mode=DEFAULT_MODE, handle=None):
+ def __init__(self, name, mode=DEFAULT_MODE, handle=None,
+ use_errno=False,
+ use_last_error=False):
self._name = name
+ flags = self._func_flags_
+ if use_errno:
+ flags |= _FUNCFLAG_USE_ERRNO
+ if use_last_error:
+ flags |= _FUNCFLAG_USE_LASTERROR
+
+ class _FuncPtr(_CFuncPtr):
+ _flags_ = flags
+ _restype_ = self._func_restype_
+ self._FuncPtr = _FuncPtr
+
if handle is None:
self._handle = _dlopen(self._name, mode)
else:
@@ -345,9 +375,7 @@
access Python API functions. The GIL is not released, and
Python exceptions are handled correctly.
"""
- class _FuncPtr(_CFuncPtr):
- _flags_ = _FUNCFLAG_CDECL | _FUNCFLAG_PYTHONAPI
- _restype_ = c_int # default, can be overridden in instances
+ _func_flags_ = _FUNCFLAG_CDECL | _FUNCFLAG_PYTHONAPI
if _os.name in ("nt", "ce"):
@@ -355,9 +383,7 @@
"""This class represents a dll exporting functions using the
Windows stdcall calling convention.
"""
- class _FuncPtr(_CFuncPtr):
- _flags_ = _FUNCFLAG_STDCALL
- _restype_ = c_int # default, can be overridden in instances
+ _func_flags_ = _FUNCFLAG_STDCALL
# XXX Hm, what about HRESULT as normal parameter?
# Mustn't it derive from c_long then?
@@ -381,9 +407,8 @@
HRESULT error values are automatically raised as WindowsError
exceptions.
"""
- class _FuncPtr(_CFuncPtr):
- _flags_ = _FUNCFLAG_STDCALL
- _restype_ = HRESULT
+ _func_flags_ = _FUNCFLAG_STDCALL
+ _func_restype_ = HRESULT
class LibraryLoader(object):
def __init__(self, dlltype):
@@ -421,6 +446,7 @@
GetLastError = windll.kernel32.GetLastError
else:
GetLastError = windll.coredll.GetLastError
+ from _ctypes import get_last_error, set_last_error
def WinError(code=None, descr=None):
if code is None:
Modified: python/branches/py3k/Modules/_ctypes/_ctypes.c
==============================================================================
--- python/branches/py3k/Modules/_ctypes/_ctypes.c (original)
+++ python/branches/py3k/Modules/_ctypes/_ctypes.c Fri Jun 6 11:31:40 2008
@@ -3340,7 +3340,7 @@
thunk = AllocFunctionCallback(callable,
dict->argtypes,
dict->restype,
- dict->flags & FUNCFLAG_CDECL);
+ dict->flags);
if (!thunk)
return NULL;
@@ -5333,6 +5333,8 @@
PyModule_AddObject(m, "FUNCFLAG_STDCALL", PyLong_FromLong(FUNCFLAG_STDCALL));
#endif
PyModule_AddObject(m, "FUNCFLAG_CDECL", PyLong_FromLong(FUNCFLAG_CDECL));
+ PyModule_AddObject(m, "FUNCFLAG_USE_ERRNO", PyLong_FromLong(FUNCFLAG_USE_ERRNO));
+ PyModule_AddObject(m, "FUNCFLAG_USE_LASTERROR", PyLong_FromLong(FUNCFLAG_USE_LASTERROR));
PyModule_AddObject(m, "FUNCFLAG_PYTHONAPI", PyLong_FromLong(FUNCFLAG_PYTHONAPI));
PyModule_AddStringConstant(m, "__version__", "1.1.0");
Modified: python/branches/py3k/Modules/_ctypes/callbacks.c
==============================================================================
--- python/branches/py3k/Modules/_ctypes/callbacks.c (original)
+++ python/branches/py3k/Modules/_ctypes/callbacks.c Fri Jun 6 11:31:40 2008
@@ -185,12 +185,15 @@
SETFUNC setfunc,
PyObject *callable,
PyObject *converters,
+ int flags,
void **pArgs)
{
Py_ssize_t i;
PyObject *result;
PyObject *arglist = NULL;
Py_ssize_t nArgs;
+ PyObject *error_object = NULL;
+ int *space;
#ifdef WITH_THREAD
PyGILState_STATE state = PyGILState_Ensure();
#endif
@@ -267,8 +270,41 @@
#define CHECK(what, x) \
if (x == NULL) _AddTraceback(what, "_ctypes/callbacks.c", __LINE__ - 1), PyErr_Print()
+ if (flags & (FUNCFLAG_USE_ERRNO | FUNCFLAG_USE_LASTERROR)) {
+ error_object = get_error_object(&space);
+ if (error_object == NULL)
+ goto Done;
+ if (flags & FUNCFLAG_USE_ERRNO) {
+ int temp = space[0];
+ space[0] = errno;
+ errno = temp;
+ }
+#ifdef MS_WIN32
+ if (flags & FUNCFLAG_USE_LASTERROR) {
+ int temp = space[1];
+ space[1] = GetLastError();
+ SetLastError(temp);
+ }
+#endif
+ }
+
result = PyObject_CallObject(callable, arglist);
CHECK("'calling callback function'", result);
+
+#ifdef MS_WIN32
+ if (flags & FUNCFLAG_USE_LASTERROR) {
+ int temp = space[1];
+ space[1] = GetLastError();
+ SetLastError(temp);
+ }
+#endif
+ if (flags & FUNCFLAG_USE_ERRNO) {
+ int temp = space[0];
+ space[0] = errno;
+ errno = temp;
+ }
+ Py_XDECREF(error_object);
+
if ((restype != &ffi_type_void) && result) {
PyObject *keep;
assert(setfunc);
@@ -319,6 +355,7 @@
p->setfunc,
p->callable,
p->converters,
+ p->flags,
args);
}
@@ -348,7 +385,7 @@
CThunkObject *AllocFunctionCallback(PyObject *callable,
PyObject *converters,
PyObject *restype,
- int is_cdecl)
+ int flags)
{
int result;
CThunkObject *p;
@@ -368,6 +405,7 @@
goto error;
}
+ p->flags = flags;
for (i = 0; i < nArgs; ++i) {
PyObject *cnv = PySequence_GetItem(converters, i);
if (cnv == NULL)
@@ -395,7 +433,7 @@
cc = FFI_DEFAULT_ABI;
#if defined(MS_WIN32) && !defined(_WIN32_WCE) && !defined(MS_WIN64)
- if (is_cdecl == 0)
+ if ((flags & FUNCFLAG_CDECL) == 0)
cc = FFI_STDCALL;
#endif
result = ffi_prep_cif(&p->cif, cc,
Modified: python/branches/py3k/Modules/_ctypes/callproc.c
==============================================================================
--- python/branches/py3k/Modules/_ctypes/callproc.c (original)
+++ python/branches/py3k/Modules/_ctypes/callproc.c Fri Jun 6 11:31:40 2008
@@ -78,7 +78,129 @@
#define DONT_USE_SEH
#endif
+/*
+ ctypes maintains thread-local storage that has space for two error numbers:
+ private copies of the system 'errno' value and, on Windows, the system error code
+ accessed by the GetLastError() and SetLastError() api functions.
+
+ Foreign functions created with CDLL(..., use_errno=True), when called, swap
+ the system 'errno' value with the private copy just before the actual
+ function call, and swapped again immediately afterwards. The 'use_errno'
+ parameter defaults to False, in this case 'ctypes_errno' is not touched.
+
+ On Windows, foreign functions created with CDLL(..., use_last_error=True) or
+ WinDLL(..., use_last_error=True) swap the system LastError value with the
+ ctypes private copy.
+
+ The values are also swapped immeditately before and after ctypes callback
+ functions are called, if the callbacks are constructed using the new
+ optional use_errno parameter set to True: CFUNCTYPE(..., use_errno=TRUE) or
+ WINFUNCTYPE(..., use_errno=True).
+
+ New ctypes functions are provided to access the ctypes private copies from
+ Python:
+
+ - ctypes.set_errno(value) and ctypes.set_last_error(value) store 'value' in
+ the private copy and returns the previous value.
+
+ - ctypes.get_errno() and ctypes.get_last_error() returns the current ctypes
+ private copies value.
+*/
+
+/*
+ This function creates and returns a thread-local Python object that has
+ space to store two integer error numbers; once created the Python object is
+ kept alive in the thread state dictionary as long as the thread itself.
+*/
+PyObject *
+get_error_object(int **pspace)
+{
+ PyObject *dict = PyThreadState_GetDict();
+ PyObject *errobj;
+ if (dict == 0) {
+ PyErr_SetString(PyExc_RuntimeError,
+ "cannot get thread state");
+ return NULL;
+ }
+ errobj = PyDict_GetItemString(dict, "ctypes.error_object");
+ if (errobj)
+ Py_INCREF(errobj);
+ else {
+ void *space = PyMem_Malloc(sizeof(int) * 2);
+ if (space == NULL)
+ return NULL;
+ memset(space, 0, sizeof(int) * 2);
+ errobj = PyCObject_FromVoidPtr(space, PyMem_Free);
+ if (errobj == NULL)
+ return NULL;
+ if (-1 == PyDict_SetItemString(dict, "ctypes.error_object",
+ errobj)) {
+ Py_DECREF(errobj);
+ return NULL;
+ }
+ }
+ *pspace = (int *)PyCObject_AsVoidPtr(errobj);
+ return errobj;
+}
+
+static PyObject *
+get_error_internal(PyObject *self, PyObject *args, int index)
+{
+ int *space;
+ PyObject *errobj = get_error_object(&space);
+ PyObject *result;
+
+ if (errobj == NULL)
+ return NULL;
+ result = PyLong_FromLong(space[index]);
+ Py_DECREF(errobj);
+ return result;
+}
+
+static PyObject *
+set_error_internal(PyObject *self, PyObject *args, int index)
+{
+ int new_errno, old_errno;
+ PyObject *errobj;
+ int *space;
+
+ if (!PyArg_ParseTuple(args, "i", &new_errno))
+ return NULL;
+ errobj = get_error_object(&space);
+ if (errobj == NULL)
+ return NULL;
+ old_errno = space[index];
+ space[index] = new_errno;
+ Py_DECREF(errobj);
+ return PyLong_FromLong(old_errno);
+}
+
+static PyObject *
+get_errno(PyObject *self, PyObject *args)
+{
+ return get_error_internal(self, args, 0);
+}
+
+static PyObject *
+set_errno(PyObject *self, PyObject *args)
+{
+ return set_error_internal(self, args, 0);
+}
+
#ifdef MS_WIN32
+
+static PyObject *
+get_last_error(PyObject *self, PyObject *args)
+{
+ return get_error_internal(self, args, 1);
+}
+
+static PyObject *
+set_last_error(PyObject *self, PyObject *args)
+{
+ return set_error_internal(self, args, 1);
+}
+
PyObject *ComError;
static TCHAR *FormatError(DWORD code)
@@ -614,6 +736,8 @@
#ifdef WITH_THREAD
PyThreadState *_save = NULL; /* For Py_BLOCK_THREADS and Py_UNBLOCK_THREADS */
#endif
+ PyObject *error_object = NULL;
+ int *space;
ffi_cif cif;
int cc;
#ifdef MS_WIN32
@@ -645,11 +769,26 @@
return -1;
}
+ if (flags & (FUNCFLAG_USE_ERRNO | FUNCFLAG_USE_LASTERROR)) {
+ error_object = get_error_object(&space);
+ if (error_object == NULL)
+ return -1;
+ }
#ifdef WITH_THREAD
if ((flags & FUNCFLAG_PYTHONAPI) == 0)
Py_UNBLOCK_THREADS
#endif
+ if (flags & FUNCFLAG_USE_ERRNO) {
+ int temp = space[0];
+ space[0] = errno;
+ errno = temp;
+ }
#ifdef MS_WIN32
+ if (flags & FUNCFLAG_USE_LASTERROR) {
+ int temp = space[1];
+ space[1] = GetLastError();
+ SetLastError(temp);
+ }
#ifndef DONT_USE_SEH
__try {
#endif
@@ -664,7 +803,18 @@
;
}
#endif
+ if (flags & FUNCFLAG_USE_LASTERROR) {
+ int temp = space[1];
+ space[1] = GetLastError();
+ SetLastError(temp);
+ }
#endif
+ if (flags & FUNCFLAG_USE_ERRNO) {
+ int temp = space[0];
+ space[0] = errno;
+ errno = temp;
+ }
+ Py_XDECREF(error_object);
#ifdef WITH_THREAD
if ((flags & FUNCFLAG_PYTHONAPI) == 0)
Py_BLOCK_THREADS
@@ -1658,6 +1808,8 @@
}
PyMethodDef module_methods[] = {
+ {"get_errno", get_errno, METH_NOARGS},
+ {"set_errno", set_errno, METH_VARARGS},
{"POINTER", POINTER, METH_O },
{"pointer", pointer, METH_O },
{"_unpickle", unpickle, METH_VARARGS },
@@ -1667,6 +1819,8 @@
{"set_conversion_mode", set_conversion_mode, METH_VARARGS, set_conversion_mode_doc},
#endif
#ifdef MS_WIN32
+ {"get_last_error", get_last_error, METH_NOARGS},
+ {"set_last_error", set_last_error, METH_VARARGS},
{"CopyComPointer", copy_com_pointer, METH_VARARGS, copy_com_pointer_doc},
{"FormatError", format_error, METH_VARARGS, format_error_doc},
{"LoadLibrary", load_library, METH_VARARGS, load_library_doc},
Modified: python/branches/py3k/Modules/_ctypes/ctypes.h
==============================================================================
--- python/branches/py3k/Modules/_ctypes/ctypes.h (original)
+++ python/branches/py3k/Modules/_ctypes/ctypes.h Fri Jun 6 11:31:40 2008
@@ -56,6 +56,7 @@
PyObject_VAR_HEAD
ffi_closure *pcl; /* the C callable */
ffi_cif cif;
+ int flags;
PyObject *converters;
PyObject *callable;
PyObject *restype;
@@ -154,7 +155,7 @@
extern CThunkObject *AllocFunctionCallback(PyObject *callable,
PyObject *converters,
PyObject *restype,
- int stdcall);
+ int flags);
/* a table entry describing a predefined ctypes type */
struct fielddesc {
char code;
@@ -280,6 +281,8 @@
#define FUNCFLAG_CDECL 0x1
#define FUNCFLAG_HRESULT 0x2
#define FUNCFLAG_PYTHONAPI 0x4
+#define FUNCFLAG_USE_ERRNO 0x8
+#define FUNCFLAG_USE_LASTERROR 0x10
#define TYPEFLAG_ISPOINTER 0x100
#define TYPEFLAG_HASPOINTER 0x200
@@ -356,6 +359,7 @@
extern int IsSimpleSubType(PyObject *obj);
extern PyObject *_pointer_type_cache;
+PyObject *get_error_object(int **pspace);
#ifdef MS_WIN32
extern PyObject *ComError;
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