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"""create and manipulate C data types in Python"""
import os as _os, sys as _sys
__version__ = "1.1.0"
from _ctypes import Union, Structure, Array
from _ctypes import _Pointer
from _ctypes import CFuncPtr as _CFuncPtr
from _ctypes import __version__ as _ctypes_version
from _ctypes import RTLD_LOCAL, RTLD_GLOBAL
from _ctypes import ArgumentError
from struct import calcsize as _calcsize
if __version__ != _ctypes_version:
raise Exception("Version number mismatch", __version__, _ctypes_version)
if == "nt":
from _ctypes import FormatError
if == "posix" and _sys.platform == "darwin":
# On OS X 10.3, we use RTLD_GLOBAL as default mode
# because RTLD_LOCAL does not work at least on some
# libraries. OS X 10.3 is Darwin 7, so we check for
# that.
if int(_os.uname().release.split('.')[0]) < 8:
from _ctypes import FUNCFLAG_CDECL as _FUNCFLAG_CDECL, \
# WINOLEAPI_(type)
# STDMETHOD_(type, name)
def create_string_buffer(init, size=None):
"""create_string_buffer(aBytes) -> character array
create_string_buffer(anInteger) -> character array
create_string_buffer(aBytes, anInteger) -> character array
if isinstance(init, bytes):
if size is None:
size = len(init)+1
_sys.audit("ctypes.create_string_buffer", init, size)
buftype = c_char * size
buf = buftype()
buf.value = init
return buf
elif isinstance(init, int):
_sys.audit("ctypes.create_string_buffer", None, init)
buftype = c_char * init
buf = buftype()
return buf
raise TypeError(init)
def c_buffer(init, size=None):
## "deprecated, use create_string_buffer instead"
## import warnings
## warnings.warn("c_buffer is deprecated, use create_string_buffer instead",
## DeprecationWarning, stacklevel=2)
return create_string_buffer(init, size)
_c_functype_cache = {}
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
The function prototype can be called in different ways to create a
callable object:
prototype(integer address) -> foreign function
prototype(callable) -> create and return a C callable function from callable
prototype(integer index, method name[, paramflags]) -> foreign function calling a COM method
prototype((ordinal number, dll object)[, paramflags]) -> foreign function exported by ordinal
prototype((function name, dll object)[, paramflags]) -> foreign function exported by name
if kw.pop("use_errno", False):
if kw.pop("use_last_error", False):
if kw:
raise ValueError("unexpected keyword argument(s) %s" % kw.keys())
return _c_functype_cache[(restype, argtypes, flags)]
except KeyError:
class CFunctionType(_CFuncPtr):
_argtypes_ = argtypes
_restype_ = restype
_flags_ = flags
_c_functype_cache[(restype, argtypes, flags)] = CFunctionType
return CFunctionType
if == "nt":
from _ctypes import LoadLibrary as _dlopen
_win_functype_cache = {}
def WINFUNCTYPE(restype, *argtypes, **kw):
# docstring set later (very similar to CFUNCTYPE.__doc__)
if kw.pop("use_errno", False):
if kw.pop("use_last_error", False):
if kw:
raise ValueError("unexpected keyword argument(s) %s" % kw.keys())
return _win_functype_cache[(restype, argtypes, flags)]
except KeyError:
class WinFunctionType(_CFuncPtr):
_argtypes_ = argtypes
_restype_ = restype
_flags_ = flags
_win_functype_cache[(restype, argtypes, flags)] = WinFunctionType
return WinFunctionType
if WINFUNCTYPE.__doc__:
elif == "posix":
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):
# Check if sizeof(ctypes_type) against struct.calcsize. This
# should protect somewhat against a misconfigured libffi.
from struct import calcsize
if typecode is None:
# Most _type_ codes are the same as used in struct
typecode = typ._type_
actual, required = sizeof(typ), calcsize(typecode)
if actual != required:
raise SystemError("sizeof(%s) wrong: %d instead of %d" % \
(typ, actual, required))
class py_object(_SimpleCData):
_type_ = "O"
def __repr__(self):
return super().__repr__()
except ValueError:
return "%s(<NULL>)" % type(self).__name__
_check_size(py_object, "P")
class c_short(_SimpleCData):
_type_ = "h"
class c_ushort(_SimpleCData):
_type_ = "H"
class c_long(_SimpleCData):
_type_ = "l"
class c_ulong(_SimpleCData):
_type_ = "L"
if _calcsize("i") == _calcsize("l"):
# if int and long have the same size, make c_int an alias for c_long
c_int = c_long
c_uint = c_ulong
class c_int(_SimpleCData):
_type_ = "i"
class c_uint(_SimpleCData):
_type_ = "I"
class c_float(_SimpleCData):
_type_ = "f"
class c_double(_SimpleCData):
_type_ = "d"
class c_longdouble(_SimpleCData):
_type_ = "g"
if sizeof(c_longdouble) == sizeof(c_double):
c_longdouble = c_double
if _calcsize("l") == _calcsize("q"):
# if long and long long have the same size, make c_longlong an alias for c_long
c_longlong = c_long
c_ulonglong = c_ulong
class c_longlong(_SimpleCData):
_type_ = "q"
class c_ulonglong(_SimpleCData):
_type_ = "Q"
## def from_param(cls, val):
## return ('d', float(val), val)
## from_param = classmethod(from_param)
class c_ubyte(_SimpleCData):
_type_ = "B"
c_ubyte.__ctype_le__ = c_ubyte.__ctype_be__ = c_ubyte
# backward compatibility:
##c_uchar = c_ubyte
class c_byte(_SimpleCData):
_type_ = "b"
c_byte.__ctype_le__ = c_byte.__ctype_be__ = c_byte
class c_char(_SimpleCData):
_type_ = "c"
c_char.__ctype_le__ = c_char.__ctype_be__ = c_char
class c_char_p(_SimpleCData):
_type_ = "z"
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, c_void_p.from_buffer(self).value)
_check_size(c_char_p, "P")
class c_void_p(_SimpleCData):
_type_ = "P"
c_voidp = c_void_p # backwards compatibility (to a bug)
class c_bool(_SimpleCData):
_type_ = "?"
from _ctypes import POINTER, pointer, _pointer_type_cache
class c_wchar_p(_SimpleCData):
_type_ = "Z"
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, c_void_p.from_buffer(self).value)
class c_wchar(_SimpleCData):
_type_ = "u"
def _reset_cache():
if == "nt":
# _SimpleCData.c_wchar_p_from_param
POINTER(c_wchar).from_param = c_wchar_p.from_param
# _SimpleCData.c_char_p_from_param
POINTER(c_char).from_param = c_char_p.from_param
_pointer_type_cache[None] = c_void_p
def create_unicode_buffer(init, size=None):
"""create_unicode_buffer(aString) -> character array
create_unicode_buffer(anInteger) -> character array
create_unicode_buffer(aString, anInteger) -> character array
if isinstance(init, str):
if size is None:
if sizeof(c_wchar) == 2:
# UTF-16 requires a surrogate pair (2 wchar_t) for non-BMP
# characters (outside [U+0000; U+FFFF] range). +1 for trailing
# NUL character.
size = sum(2 if ord(c) > 0xFFFF else 1 for c in init) + 1
# 32-bit wchar_t (1 wchar_t per Unicode character). +1 for
# trailing NUL character.
size = len(init) + 1
_sys.audit("ctypes.create_unicode_buffer", init, size)
buftype = c_wchar * size
buf = buftype()
buf.value = init
return buf
elif isinstance(init, int):
_sys.audit("ctypes.create_unicode_buffer", None, init)
buftype = c_wchar * init
buf = buftype()
return buf
raise TypeError(init)
# XXX Deprecated
def SetPointerType(pointer, cls):
if _pointer_type_cache.get(cls, None) is not None:
raise RuntimeError("This type already exists in the cache")
if id(pointer) not in _pointer_type_cache:
raise RuntimeError("What's this???")
_pointer_type_cache[cls] = pointer
del _pointer_type_cache[id(pointer)]
# XXX Deprecated
def ARRAY(typ, len):
return typ * len
class CDLL(object):
"""An instance of this class represents a loaded dll/shared
library, exporting functions using the standard C calling
convention (named 'cdecl' on Windows).
The exported functions can be accessed as attributes, or by
indexing with the function name. Examples:
<obj>.qsort -> callable object
<obj>['qsort'] -> callable object
Calling the functions releases the Python GIL during the call and
reacquires it afterwards.
_func_flags_ = _FUNCFLAG_CDECL
_func_restype_ = c_int
# default values for repr
_name = '<uninitialized>'
_handle = 0
_FuncPtr = None
def __init__(self, name, mode=DEFAULT_MODE, handle=None,
self._name = name
flags = self._func_flags_
if use_errno:
if use_last_error:
if _sys.platform.startswith("aix"):
"""When the name contains ".a(" and ends with ")",
e.g., "libFOO.a(" - this is taken to be an
archive(member) syntax for dlopen(), and the mode is adjusted.
Otherwise, name is presented to dlopen() as a file argument.
if name and name.endswith(")") and ".a(" in name:
mode |= ( _os.RTLD_MEMBER | _os.RTLD_NOW )
if == "nt":
if winmode is not None:
mode = winmode
import nt
if '/' in name or '\\' in name:
self._name = nt._getfullpathname(self._name)
class _FuncPtr(_CFuncPtr):
_flags_ = flags
_restype_ = self._func_restype_
self._FuncPtr = _FuncPtr
if handle is None:
self._handle = _dlopen(self._name, mode)
self._handle = handle
def __repr__(self):
return "<%s '%s', handle %x at %#x>" % \
(self.__class__.__name__, self._name,
(self._handle & (_sys.maxsize*2 + 1)),
id(self) & (_sys.maxsize*2 + 1))
def __getattr__(self, name):
if name.startswith('__') and name.endswith('__'):
raise AttributeError(name)
func = self.__getitem__(name)
setattr(self, name, func)
return func
def __getitem__(self, name_or_ordinal):
func = self._FuncPtr((name_or_ordinal, self))
if not isinstance(name_or_ordinal, int):
func.__name__ = name_or_ordinal
return func
class PyDLL(CDLL):
"""This class represents the Python library itself. It allows
accessing Python API functions. The GIL is not released, and
Python exceptions are handled correctly.
if == "nt":
class WinDLL(CDLL):
"""This class represents a dll exporting functions using the
Windows stdcall calling convention.
_func_flags_ = _FUNCFLAG_STDCALL
# XXX Hm, what about HRESULT as normal parameter?
# Mustn't it derive from c_long then?
from _ctypes import _check_HRESULT, _SimpleCData
class HRESULT(_SimpleCData):
_type_ = "l"
# _check_retval_ is called with the function's result when it
# is used as restype. It checks for the FAILED bit, and
# raises an OSError if it is set.
# The _check_retval_ method is implemented in C, so that the
# method definition itself is not included in the traceback
# when it raises an error - that is what we want (and Python
# doesn't have a way to raise an exception in the caller's
# frame).
_check_retval_ = _check_HRESULT
class OleDLL(CDLL):
"""This class represents a dll exporting functions using the
Windows stdcall calling convention, and returning HRESULT.
HRESULT error values are automatically raised as OSError
_func_flags_ = _FUNCFLAG_STDCALL
_func_restype_ = HRESULT
class LibraryLoader(object):
def __init__(self, dlltype):
self._dlltype = dlltype
def __getattr__(self, name):
if name[0] == '_':
raise AttributeError(name)
dll = self._dlltype(name)
setattr(self, name, dll)
return dll
def __getitem__(self, name):
return getattr(self, name)
def LoadLibrary(self, name):
return self._dlltype(name)
cdll = LibraryLoader(CDLL)
pydll = LibraryLoader(PyDLL)
if == "nt":
pythonapi = PyDLL("python dll", None, _sys.dllhandle)
elif _sys.platform == "cygwin":
pythonapi = PyDLL("libpython%d.%d.dll" % _sys.version_info[:2])
pythonapi = PyDLL(None)
if == "nt":
windll = LibraryLoader(WinDLL)
oledll = LibraryLoader(OleDLL)
GetLastError = windll.kernel32.GetLastError
from _ctypes import get_last_error, set_last_error
def WinError(code=None, descr=None):
if code is None:
code = GetLastError()
if descr is None:
descr = FormatError(code).strip()
return OSError(None, descr, None, code)
if sizeof(c_uint) == sizeof(c_void_p):
c_size_t = c_uint
c_ssize_t = c_int
elif sizeof(c_ulong) == sizeof(c_void_p):
c_size_t = c_ulong
c_ssize_t = c_long
elif sizeof(c_ulonglong) == sizeof(c_void_p):
c_size_t = c_ulonglong
c_ssize_t = c_longlong
# functions
from _ctypes import _memmove_addr, _memset_addr, _string_at_addr, _cast_addr
## void *memmove(void *, const void *, size_t);
memmove = CFUNCTYPE(c_void_p, c_void_p, c_void_p, c_size_t)(_memmove_addr)
## void *memset(void *, int, size_t)
memset = CFUNCTYPE(c_void_p, c_void_p, c_int, c_size_t)(_memset_addr)
def PYFUNCTYPE(restype, *argtypes):
class CFunctionType(_CFuncPtr):
_argtypes_ = argtypes
_restype_ = restype
return CFunctionType
_cast = PYFUNCTYPE(py_object, c_void_p, py_object, py_object)(_cast_addr)
def cast(obj, typ):
return _cast(obj, obj, typ)
_string_at = PYFUNCTYPE(py_object, c_void_p, c_int)(_string_at_addr)
def string_at(ptr, size=-1):
"""string_at(addr[, size]) -> string
Return the string at addr."""
return _string_at(ptr, size)
from _ctypes import _wstring_at_addr
except ImportError:
_wstring_at = PYFUNCTYPE(py_object, c_void_p, c_int)(_wstring_at_addr)
def wstring_at(ptr, size=-1):
"""wstring_at(addr[, size]) -> string
Return the string at addr."""
return _wstring_at(ptr, size)
if == "nt": # COM stuff
def DllGetClassObject(rclsid, riid, ppv):
ccom = __import__("comtypes.server.inprocserver", globals(), locals(), ['*'])
except ImportError:
return -2147221231 # CLASS_E_CLASSNOTAVAILABLE
return ccom.DllGetClassObject(rclsid, riid, ppv)
def DllCanUnloadNow():
ccom = __import__("comtypes.server.inprocserver", globals(), locals(), ['*'])
except ImportError:
return 0 # S_OK
return ccom.DllCanUnloadNow()
from ctypes._endian import BigEndianStructure, LittleEndianStructure
# Fill in specifically-sized types
c_int8 = c_byte
c_uint8 = c_ubyte
for kind in [c_short, c_int, c_long, c_longlong]:
if sizeof(kind) == 2: c_int16 = kind
elif sizeof(kind) == 4: c_int32 = kind
elif sizeof(kind) == 8: c_int64 = kind
for kind in [c_ushort, c_uint, c_ulong, c_ulonglong]:
if sizeof(kind) == 2: c_uint16 = kind
elif sizeof(kind) == 4: c_uint32 = kind
elif sizeof(kind) == 8: c_uint64 = kind
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