我们从Python开源项目中，提取了以下15个代码示例，用于说明如何使用ctypes._SimpleCData()。
def synchronized(obj, lock=None): assert not isinstance(obj, SynchronizedBase), 'object already synchronized' if isinstance(obj, ctypes._SimpleCData): return Synchronized(obj, lock) elif isinstance(obj, ctypes.Array): if obj._type_ is ctypes.c_char: return SynchronizedString(obj, lock) return SynchronizedArray(obj, lock) else: cls = type(obj) try: scls = class_cache[cls] except KeyError: names = [field[0] for field in cls._fields_] d = dict((name, make_property(name)) for name in names) classname = 'Synchronized' + cls.__name__ scls = class_cache[cls] = type(classname, (SynchronizedBase,), d) return scls(obj, lock) # # Functions for pickling/unpickling #
def synchronized(obj, lock=None, ctx=None): assert not isinstance(obj, SynchronizedBase), 'object already synchronized' ctx = ctx or get_context() if isinstance(obj, ctypes._SimpleCData): return Synchronized(obj, lock, ctx) elif isinstance(obj, ctypes.Array): if obj._type_ is ctypes.c_char: return SynchronizedString(obj, lock, ctx) return SynchronizedArray(obj, lock, ctx) else: cls = type(obj) try: scls = class_cache[cls] except KeyError: names = [field[0] for field in cls._fields_] d = dict((name, make_property(name)) for name in names) classname = 'Synchronized' + cls.__name__ scls = class_cache[cls] = type(classname, (SynchronizedBase,), d) return scls(obj, lock, ctx) # # Functions for pickling/unpickling #
def test_itemsize(self): for size in [1, 2, 4, 8]: a = Array((1,), 'i', size) ct = a._ctype self.assertTrue(issubclass(ct, ctypes._SimpleCData)) self.assertEqual(sizeof(ct), size)
def _ioc_type_size(size): if isinstance(size, type) and issubclass(size, ctypes._SimpleCData): return ctypes.sizeof(size) elif isinstance(size, int): return size else: raise TypeError('Invalid type for size: {size_type}'.format(size_type=size.__class__.__name__))
def check_ctypes_datatype(datatype): valid_datatypes = ( ctypes._SimpleCData, ctypes.Union, ctypes.BigEndianStructure, ctypes.LittleEndianStructure, ctypes.Structure, ) for t in valid_datatypes: if issubclass(datatype, t): return raise TypeError('datatype must be a ctypes data type, but was {}'.format(datatype.__name__))
def ioctl_fn_ptr_r(request, datatype, return_python=None): """ Create a helper function for invoking a ioctl() read call. This function creates a helper function for creating a ioctl() read function. It will call the ioctl() function with a pointer to data, and return the contents of the data after the call. If the datatype is a integer type (int, long, etc), it will be returned as a python int or long. :param request: The ioctl request to call. :param datatype: The data type of the data returned by the ioctl() call. :param return_python: Whether we should attempt to convert the return data to a Python value. Defaults to True for fundamental ctypes data types. :return: A function for invoking the specified ioctl(). :Example: :: import ctypes import os import ioctl import ioctl.linux RNDGETENTCNT = ioctl.linux.IOR('R', 0x00, ctypes.c_int) rndgetentcnt = ioctl.ioctl_fn_ptr_r(RNDGETENTCNT, ctypes.c_int) fd = os.open('/dev/random', os.O_RDONLY) entropy_avail = rndgetentcnt(fd) """ check_request(request) check_ctypes_datatype(datatype) if return_python is not None and not isinstance(return_python, bool): raise TypeError('return_python must be None or a boolean, but was {}'.format(return_python.__class__.__name__)) if return_python is None: return_python = issubclass(datatype, ctypes._SimpleCData) def fn(fd): check_fd(fd) value = datatype() ioctl(fd, request, ctypes.byref(value)) if return_python: return value.value else: return value return fn
def ioctl_fn_ptr_wr(request, datatype, return_python=None): """ Create a helper function for invoking a ioctl() read & write call. This function creates a helper function for a ioctl() operation that both reads and writes data. Typically the case is a ioctl() operation that receives a pointer to data, performs an operation and updates the data at the pointer. E.g. if you have a ioctl() call like:: int timeout = 45; ioctl(fd, WDIOF_SETTIMEOUT, &timeout); printf("Actual timeout: %d\n", timeout); :param request: The ioctl request to call. :param datatype: The data type of the data to be passed to the ioctl() call. :param return_python: Whether we should attempt to convert the return data to a Python value. Defaults to True for fundamental ctypes data types. :return: A function for invoking the specified ioctl(). :Example: :: import ctypes import os import ioctl WDIOF_SETTIMEOUT = 0x0080 wdiof_settimeout = ioctl.ioctl_fn_ptr_wr(WDIOF_SETTIMEOUT, ctypes.c_int) fd = os.open('/dev/watchdog', os.O_RDONLY) actual_timeout = wdiof_settimeout(fd, 60) """ check_request(request) check_ctypes_datatype(datatype) if return_python is not None and not isinstance(return_python, bool): raise TypeError('return_python must be None or a boolean, but was {}'.format(return_python.__class__.__name__)) if return_python is None: return_python = issubclass(datatype, ctypes._SimpleCData) def fn(fd, value): check_fd(fd) value = datatype(value) ioctl(fd, request, ctypes.byref(value)) if return_python: return value.value else: return value return fn
