forked from STI/Astroport.ONE
966 lines
41 KiB
Python
966 lines
41 KiB
Python
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import sys, types
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from .lock import allocate_lock
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from .error import CDefError
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from . import model
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try:
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callable
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except NameError:
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# Python 3.1
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from collections import Callable
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callable = lambda x: isinstance(x, Callable)
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try:
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basestring
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except NameError:
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# Python 3.x
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basestring = str
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_unspecified = object()
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class FFI(object):
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r'''
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The main top-level class that you instantiate once, or once per module.
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Example usage:
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ffi = FFI()
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ffi.cdef("""
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int printf(const char *, ...);
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""")
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C = ffi.dlopen(None) # standard library
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-or-
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C = ffi.verify() # use a C compiler: verify the decl above is right
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C.printf("hello, %s!\n", ffi.new("char[]", "world"))
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'''
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def __init__(self, backend=None):
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"""Create an FFI instance. The 'backend' argument is used to
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select a non-default backend, mostly for tests.
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"""
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if backend is None:
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# You need PyPy (>= 2.0 beta), or a CPython (>= 2.6) with
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# _cffi_backend.so compiled.
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import _cffi_backend as backend
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from . import __version__
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if backend.__version__ != __version__:
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# bad version! Try to be as explicit as possible.
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if hasattr(backend, '__file__'):
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# CPython
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raise Exception("Version mismatch: this is the 'cffi' package version %s, located in %r. When we import the top-level '_cffi_backend' extension module, we get version %s, located in %r. The two versions should be equal; check your installation." % (
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__version__, __file__,
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backend.__version__, backend.__file__))
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else:
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# PyPy
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raise Exception("Version mismatch: this is the 'cffi' package version %s, located in %r. This interpreter comes with a built-in '_cffi_backend' module, which is version %s. The two versions should be equal; check your installation." % (
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__version__, __file__, backend.__version__))
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# (If you insist you can also try to pass the option
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# 'backend=backend_ctypes.CTypesBackend()', but don't
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# rely on it! It's probably not going to work well.)
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from . import cparser
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self._backend = backend
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self._lock = allocate_lock()
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self._parser = cparser.Parser()
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self._cached_btypes = {}
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self._parsed_types = types.ModuleType('parsed_types').__dict__
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self._new_types = types.ModuleType('new_types').__dict__
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self._function_caches = []
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self._libraries = []
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self._cdefsources = []
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self._included_ffis = []
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self._windows_unicode = None
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self._init_once_cache = {}
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self._cdef_version = None
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self._embedding = None
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self._typecache = model.get_typecache(backend)
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if hasattr(backend, 'set_ffi'):
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backend.set_ffi(self)
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for name in list(backend.__dict__):
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if name.startswith('RTLD_'):
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setattr(self, name, getattr(backend, name))
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#
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with self._lock:
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self.BVoidP = self._get_cached_btype(model.voidp_type)
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self.BCharA = self._get_cached_btype(model.char_array_type)
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if isinstance(backend, types.ModuleType):
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# _cffi_backend: attach these constants to the class
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if not hasattr(FFI, 'NULL'):
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FFI.NULL = self.cast(self.BVoidP, 0)
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FFI.CData, FFI.CType = backend._get_types()
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else:
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# ctypes backend: attach these constants to the instance
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self.NULL = self.cast(self.BVoidP, 0)
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self.CData, self.CType = backend._get_types()
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self.buffer = backend.buffer
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def cdef(self, csource, override=False, packed=False, pack=None):
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"""Parse the given C source. This registers all declared functions,
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types, and global variables. The functions and global variables can
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then be accessed via either 'ffi.dlopen()' or 'ffi.verify()'.
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The types can be used in 'ffi.new()' and other functions.
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If 'packed' is specified as True, all structs declared inside this
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cdef are packed, i.e. laid out without any field alignment at all.
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Alternatively, 'pack' can be a small integer, and requests for
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alignment greater than that are ignored (pack=1 is equivalent to
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packed=True).
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"""
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self._cdef(csource, override=override, packed=packed, pack=pack)
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def embedding_api(self, csource, packed=False, pack=None):
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self._cdef(csource, packed=packed, pack=pack, dllexport=True)
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if self._embedding is None:
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self._embedding = ''
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def _cdef(self, csource, override=False, **options):
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if not isinstance(csource, str): # unicode, on Python 2
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if not isinstance(csource, basestring):
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raise TypeError("cdef() argument must be a string")
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csource = csource.encode('ascii')
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with self._lock:
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self._cdef_version = object()
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self._parser.parse(csource, override=override, **options)
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self._cdefsources.append(csource)
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if override:
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for cache in self._function_caches:
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cache.clear()
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finishlist = self._parser._recomplete
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if finishlist:
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self._parser._recomplete = []
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for tp in finishlist:
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tp.finish_backend_type(self, finishlist)
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def dlopen(self, name, flags=0):
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"""Load and return a dynamic library identified by 'name'.
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The standard C library can be loaded by passing None.
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Note that functions and types declared by 'ffi.cdef()' are not
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linked to a particular library, just like C headers; in the
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library we only look for the actual (untyped) symbols.
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"""
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if not (isinstance(name, basestring) or
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name is None or
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isinstance(name, self.CData)):
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raise TypeError("dlopen(name): name must be a file name, None, "
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"or an already-opened 'void *' handle")
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with self._lock:
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lib, function_cache = _make_ffi_library(self, name, flags)
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self._function_caches.append(function_cache)
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self._libraries.append(lib)
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return lib
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def dlclose(self, lib):
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"""Close a library obtained with ffi.dlopen(). After this call,
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access to functions or variables from the library will fail
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(possibly with a segmentation fault).
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"""
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type(lib).__cffi_close__(lib)
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def _typeof_locked(self, cdecl):
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# call me with the lock!
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key = cdecl
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if key in self._parsed_types:
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return self._parsed_types[key]
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#
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if not isinstance(cdecl, str): # unicode, on Python 2
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cdecl = cdecl.encode('ascii')
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#
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type = self._parser.parse_type(cdecl)
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really_a_function_type = type.is_raw_function
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if really_a_function_type:
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type = type.as_function_pointer()
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btype = self._get_cached_btype(type)
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result = btype, really_a_function_type
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self._parsed_types[key] = result
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return result
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def _typeof(self, cdecl, consider_function_as_funcptr=False):
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# string -> ctype object
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try:
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result = self._parsed_types[cdecl]
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except KeyError:
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with self._lock:
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result = self._typeof_locked(cdecl)
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#
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btype, really_a_function_type = result
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if really_a_function_type and not consider_function_as_funcptr:
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raise CDefError("the type %r is a function type, not a "
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"pointer-to-function type" % (cdecl,))
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return btype
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def typeof(self, cdecl):
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"""Parse the C type given as a string and return the
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corresponding <ctype> object.
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It can also be used on 'cdata' instance to get its C type.
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"""
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if isinstance(cdecl, basestring):
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return self._typeof(cdecl)
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if isinstance(cdecl, self.CData):
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return self._backend.typeof(cdecl)
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if isinstance(cdecl, types.BuiltinFunctionType):
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res = _builtin_function_type(cdecl)
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if res is not None:
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return res
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if (isinstance(cdecl, types.FunctionType)
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and hasattr(cdecl, '_cffi_base_type')):
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with self._lock:
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return self._get_cached_btype(cdecl._cffi_base_type)
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raise TypeError(type(cdecl))
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def sizeof(self, cdecl):
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"""Return the size in bytes of the argument. It can be a
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string naming a C type, or a 'cdata' instance.
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"""
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if isinstance(cdecl, basestring):
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BType = self._typeof(cdecl)
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return self._backend.sizeof(BType)
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else:
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return self._backend.sizeof(cdecl)
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def alignof(self, cdecl):
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"""Return the natural alignment size in bytes of the C type
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given as a string.
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"""
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if isinstance(cdecl, basestring):
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cdecl = self._typeof(cdecl)
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return self._backend.alignof(cdecl)
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def offsetof(self, cdecl, *fields_or_indexes):
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"""Return the offset of the named field inside the given
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structure or array, which must be given as a C type name.
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You can give several field names in case of nested structures.
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You can also give numeric values which correspond to array
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items, in case of an array type.
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"""
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if isinstance(cdecl, basestring):
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cdecl = self._typeof(cdecl)
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return self._typeoffsetof(cdecl, *fields_or_indexes)[1]
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def new(self, cdecl, init=None):
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"""Allocate an instance according to the specified C type and
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return a pointer to it. The specified C type must be either a
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pointer or an array: ``new('X *')`` allocates an X and returns
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a pointer to it, whereas ``new('X[n]')`` allocates an array of
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n X'es and returns an array referencing it (which works
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mostly like a pointer, like in C). You can also use
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``new('X[]', n)`` to allocate an array of a non-constant
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length n.
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The memory is initialized following the rules of declaring a
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global variable in C: by default it is zero-initialized, but
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an explicit initializer can be given which can be used to
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fill all or part of the memory.
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When the returned <cdata> object goes out of scope, the memory
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is freed. In other words the returned <cdata> object has
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ownership of the value of type 'cdecl' that it points to. This
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means that the raw data can be used as long as this object is
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kept alive, but must not be used for a longer time. Be careful
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about that when copying the pointer to the memory somewhere
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else, e.g. into another structure.
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"""
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if isinstance(cdecl, basestring):
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cdecl = self._typeof(cdecl)
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return self._backend.newp(cdecl, init)
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def new_allocator(self, alloc=None, free=None,
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should_clear_after_alloc=True):
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"""Return a new allocator, i.e. a function that behaves like ffi.new()
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but uses the provided low-level 'alloc' and 'free' functions.
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'alloc' is called with the size as argument. If it returns NULL, a
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MemoryError is raised. 'free' is called with the result of 'alloc'
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as argument. Both can be either Python function or directly C
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functions. If 'free' is None, then no free function is called.
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If both 'alloc' and 'free' are None, the default is used.
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If 'should_clear_after_alloc' is set to False, then the memory
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returned by 'alloc' is assumed to be already cleared (or you are
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fine with garbage); otherwise CFFI will clear it.
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"""
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compiled_ffi = self._backend.FFI()
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allocator = compiled_ffi.new_allocator(alloc, free,
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should_clear_after_alloc)
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def allocate(cdecl, init=None):
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if isinstance(cdecl, basestring):
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cdecl = self._typeof(cdecl)
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return allocator(cdecl, init)
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return allocate
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def cast(self, cdecl, source):
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"""Similar to a C cast: returns an instance of the named C
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type initialized with the given 'source'. The source is
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casted between integers or pointers of any type.
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"""
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if isinstance(cdecl, basestring):
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cdecl = self._typeof(cdecl)
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return self._backend.cast(cdecl, source)
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def string(self, cdata, maxlen=-1):
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"""Return a Python string (or unicode string) from the 'cdata'.
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If 'cdata' is a pointer or array of characters or bytes, returns
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the null-terminated string. The returned string extends until
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the first null character, or at most 'maxlen' characters. If
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'cdata' is an array then 'maxlen' defaults to its length.
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If 'cdata' is a pointer or array of wchar_t, returns a unicode
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string following the same rules.
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If 'cdata' is a single character or byte or a wchar_t, returns
|
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it as a string or unicode string.
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If 'cdata' is an enum, returns the value of the enumerator as a
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string, or 'NUMBER' if the value is out of range.
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"""
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return self._backend.string(cdata, maxlen)
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def unpack(self, cdata, length):
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"""Unpack an array of C data of the given length,
|
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returning a Python string/unicode/list.
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If 'cdata' is a pointer to 'char', returns a byte string.
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It does not stop at the first null. This is equivalent to:
|
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ffi.buffer(cdata, length)[:]
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|
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If 'cdata' is a pointer to 'wchar_t', returns a unicode string.
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'length' is measured in wchar_t's; it is not the size in bytes.
|
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|
|
||
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If 'cdata' is a pointer to anything else, returns a list of
|
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'length' items. This is a faster equivalent to:
|
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[cdata[i] for i in range(length)]
|
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"""
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return self._backend.unpack(cdata, length)
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#def buffer(self, cdata, size=-1):
|
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# """Return a read-write buffer object that references the raw C data
|
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|
# pointed to by the given 'cdata'. The 'cdata' must be a pointer or
|
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|
# an array. Can be passed to functions expecting a buffer, or directly
|
||
|
# manipulated with:
|
||
|
#
|
||
|
# buf[:] get a copy of it in a regular string, or
|
||
|
# buf[idx] as a single character
|
||
|
# buf[:] = ...
|
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|
# buf[idx] = ... change the content
|
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# """
|
||
|
# note that 'buffer' is a type, set on this instance by __init__
|
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|
|
||
|
def from_buffer(self, cdecl, python_buffer=_unspecified,
|
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|
require_writable=False):
|
||
|
"""Return a cdata of the given type pointing to the data of the
|
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|
given Python object, which must support the buffer interface.
|
||
|
Note that this is not meant to be used on the built-in types
|
||
|
str or unicode (you can build 'char[]' arrays explicitly)
|
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|
but only on objects containing large quantities of raw data
|
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|
in some other format, like 'array.array' or numpy arrays.
|
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|
|
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The first argument is optional and default to 'char[]'.
|
||
|
"""
|
||
|
if python_buffer is _unspecified:
|
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cdecl, python_buffer = self.BCharA, cdecl
|
||
|
elif isinstance(cdecl, basestring):
|
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|
cdecl = self._typeof(cdecl)
|
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|
return self._backend.from_buffer(cdecl, python_buffer,
|
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|
require_writable)
|
||
|
|
||
|
def memmove(self, dest, src, n):
|
||
|
"""ffi.memmove(dest, src, n) copies n bytes of memory from src to dest.
|
||
|
|
||
|
Like the C function memmove(), the memory areas may overlap;
|
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|
apart from that it behaves like the C function memcpy().
|
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|
|
||
|
'src' can be any cdata ptr or array, or any Python buffer object.
|
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|
'dest' can be any cdata ptr or array, or a writable Python buffer
|
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|
object. The size to copy, 'n', is always measured in bytes.
|
||
|
|
||
|
Unlike other methods, this one supports all Python buffer including
|
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|
byte strings and bytearrays---but it still does not support
|
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|
non-contiguous buffers.
|
||
|
"""
|
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return self._backend.memmove(dest, src, n)
|
||
|
|
||
|
def callback(self, cdecl, python_callable=None, error=None, onerror=None):
|
||
|
"""Return a callback object or a decorator making such a
|
||
|
callback object. 'cdecl' must name a C function pointer type.
|
||
|
The callback invokes the specified 'python_callable' (which may
|
||
|
be provided either directly or via a decorator). Important: the
|
||
|
callback object must be manually kept alive for as long as the
|
||
|
callback may be invoked from the C level.
|
||
|
"""
|
||
|
def callback_decorator_wrap(python_callable):
|
||
|
if not callable(python_callable):
|
||
|
raise TypeError("the 'python_callable' argument "
|
||
|
"is not callable")
|
||
|
return self._backend.callback(cdecl, python_callable,
|
||
|
error, onerror)
|
||
|
if isinstance(cdecl, basestring):
|
||
|
cdecl = self._typeof(cdecl, consider_function_as_funcptr=True)
|
||
|
if python_callable is None:
|
||
|
return callback_decorator_wrap # decorator mode
|
||
|
else:
|
||
|
return callback_decorator_wrap(python_callable) # direct mode
|
||
|
|
||
|
def getctype(self, cdecl, replace_with=''):
|
||
|
"""Return a string giving the C type 'cdecl', which may be itself
|
||
|
a string or a <ctype> object. If 'replace_with' is given, it gives
|
||
|
extra text to append (or insert for more complicated C types), like
|
||
|
a variable name, or '*' to get actually the C type 'pointer-to-cdecl'.
|
||
|
"""
|
||
|
if isinstance(cdecl, basestring):
|
||
|
cdecl = self._typeof(cdecl)
|
||
|
replace_with = replace_with.strip()
|
||
|
if (replace_with.startswith('*')
|
||
|
and '&[' in self._backend.getcname(cdecl, '&')):
|
||
|
replace_with = '(%s)' % replace_with
|
||
|
elif replace_with and not replace_with[0] in '[(':
|
||
|
replace_with = ' ' + replace_with
|
||
|
return self._backend.getcname(cdecl, replace_with)
|
||
|
|
||
|
def gc(self, cdata, destructor, size=0):
|
||
|
"""Return a new cdata object that points to the same
|
||
|
data. Later, when this new cdata object is garbage-collected,
|
||
|
'destructor(old_cdata_object)' will be called.
|
||
|
|
||
|
The optional 'size' gives an estimate of the size, used to
|
||
|
trigger the garbage collection more eagerly. So far only used
|
||
|
on PyPy. It tells the GC that the returned object keeps alive
|
||
|
roughly 'size' bytes of external memory.
|
||
|
"""
|
||
|
return self._backend.gcp(cdata, destructor, size)
|
||
|
|
||
|
def _get_cached_btype(self, type):
|
||
|
assert self._lock.acquire(False) is False
|
||
|
# call me with the lock!
|
||
|
try:
|
||
|
BType = self._cached_btypes[type]
|
||
|
except KeyError:
|
||
|
finishlist = []
|
||
|
BType = type.get_cached_btype(self, finishlist)
|
||
|
for type in finishlist:
|
||
|
type.finish_backend_type(self, finishlist)
|
||
|
return BType
|
||
|
|
||
|
def verify(self, source='', tmpdir=None, **kwargs):
|
||
|
"""Verify that the current ffi signatures compile on this
|
||
|
machine, and return a dynamic library object. The dynamic
|
||
|
library can be used to call functions and access global
|
||
|
variables declared in this 'ffi'. The library is compiled
|
||
|
by the C compiler: it gives you C-level API compatibility
|
||
|
(including calling macros). This is unlike 'ffi.dlopen()',
|
||
|
which requires binary compatibility in the signatures.
|
||
|
"""
|
||
|
from .verifier import Verifier, _caller_dir_pycache
|
||
|
#
|
||
|
# If set_unicode(True) was called, insert the UNICODE and
|
||
|
# _UNICODE macro declarations
|
||
|
if self._windows_unicode:
|
||
|
self._apply_windows_unicode(kwargs)
|
||
|
#
|
||
|
# Set the tmpdir here, and not in Verifier.__init__: it picks
|
||
|
# up the caller's directory, which we want to be the caller of
|
||
|
# ffi.verify(), as opposed to the caller of Veritier().
|
||
|
tmpdir = tmpdir or _caller_dir_pycache()
|
||
|
#
|
||
|
# Make a Verifier() and use it to load the library.
|
||
|
self.verifier = Verifier(self, source, tmpdir, **kwargs)
|
||
|
lib = self.verifier.load_library()
|
||
|
#
|
||
|
# Save the loaded library for keep-alive purposes, even
|
||
|
# if the caller doesn't keep it alive itself (it should).
|
||
|
self._libraries.append(lib)
|
||
|
return lib
|
||
|
|
||
|
def _get_errno(self):
|
||
|
return self._backend.get_errno()
|
||
|
def _set_errno(self, errno):
|
||
|
self._backend.set_errno(errno)
|
||
|
errno = property(_get_errno, _set_errno, None,
|
||
|
"the value of 'errno' from/to the C calls")
|
||
|
|
||
|
def getwinerror(self, code=-1):
|
||
|
return self._backend.getwinerror(code)
|
||
|
|
||
|
def _pointer_to(self, ctype):
|
||
|
with self._lock:
|
||
|
return model.pointer_cache(self, ctype)
|
||
|
|
||
|
def addressof(self, cdata, *fields_or_indexes):
|
||
|
"""Return the address of a <cdata 'struct-or-union'>.
|
||
|
If 'fields_or_indexes' are given, returns the address of that
|
||
|
field or array item in the structure or array, recursively in
|
||
|
case of nested structures.
|
||
|
"""
|
||
|
try:
|
||
|
ctype = self._backend.typeof(cdata)
|
||
|
except TypeError:
|
||
|
if '__addressof__' in type(cdata).__dict__:
|
||
|
return type(cdata).__addressof__(cdata, *fields_or_indexes)
|
||
|
raise
|
||
|
if fields_or_indexes:
|
||
|
ctype, offset = self._typeoffsetof(ctype, *fields_or_indexes)
|
||
|
else:
|
||
|
if ctype.kind == "pointer":
|
||
|
raise TypeError("addressof(pointer)")
|
||
|
offset = 0
|
||
|
ctypeptr = self._pointer_to(ctype)
|
||
|
return self._backend.rawaddressof(ctypeptr, cdata, offset)
|
||
|
|
||
|
def _typeoffsetof(self, ctype, field_or_index, *fields_or_indexes):
|
||
|
ctype, offset = self._backend.typeoffsetof(ctype, field_or_index)
|
||
|
for field1 in fields_or_indexes:
|
||
|
ctype, offset1 = self._backend.typeoffsetof(ctype, field1, 1)
|
||
|
offset += offset1
|
||
|
return ctype, offset
|
||
|
|
||
|
def include(self, ffi_to_include):
|
||
|
"""Includes the typedefs, structs, unions and enums defined
|
||
|
in another FFI instance. Usage is similar to a #include in C,
|
||
|
where a part of the program might include types defined in
|
||
|
another part for its own usage. Note that the include()
|
||
|
method has no effect on functions, constants and global
|
||
|
variables, which must anyway be accessed directly from the
|
||
|
lib object returned by the original FFI instance.
|
||
|
"""
|
||
|
if not isinstance(ffi_to_include, FFI):
|
||
|
raise TypeError("ffi.include() expects an argument that is also of"
|
||
|
" type cffi.FFI, not %r" % (
|
||
|
type(ffi_to_include).__name__,))
|
||
|
if ffi_to_include is self:
|
||
|
raise ValueError("self.include(self)")
|
||
|
with ffi_to_include._lock:
|
||
|
with self._lock:
|
||
|
self._parser.include(ffi_to_include._parser)
|
||
|
self._cdefsources.append('[')
|
||
|
self._cdefsources.extend(ffi_to_include._cdefsources)
|
||
|
self._cdefsources.append(']')
|
||
|
self._included_ffis.append(ffi_to_include)
|
||
|
|
||
|
def new_handle(self, x):
|
||
|
return self._backend.newp_handle(self.BVoidP, x)
|
||
|
|
||
|
def from_handle(self, x):
|
||
|
return self._backend.from_handle(x)
|
||
|
|
||
|
def release(self, x):
|
||
|
self._backend.release(x)
|
||
|
|
||
|
def set_unicode(self, enabled_flag):
|
||
|
"""Windows: if 'enabled_flag' is True, enable the UNICODE and
|
||
|
_UNICODE defines in C, and declare the types like TCHAR and LPTCSTR
|
||
|
to be (pointers to) wchar_t. If 'enabled_flag' is False,
|
||
|
declare these types to be (pointers to) plain 8-bit characters.
|
||
|
This is mostly for backward compatibility; you usually want True.
|
||
|
"""
|
||
|
if self._windows_unicode is not None:
|
||
|
raise ValueError("set_unicode() can only be called once")
|
||
|
enabled_flag = bool(enabled_flag)
|
||
|
if enabled_flag:
|
||
|
self.cdef("typedef wchar_t TBYTE;"
|
||
|
"typedef wchar_t TCHAR;"
|
||
|
"typedef const wchar_t *LPCTSTR;"
|
||
|
"typedef const wchar_t *PCTSTR;"
|
||
|
"typedef wchar_t *LPTSTR;"
|
||
|
"typedef wchar_t *PTSTR;"
|
||
|
"typedef TBYTE *PTBYTE;"
|
||
|
"typedef TCHAR *PTCHAR;")
|
||
|
else:
|
||
|
self.cdef("typedef char TBYTE;"
|
||
|
"typedef char TCHAR;"
|
||
|
"typedef const char *LPCTSTR;"
|
||
|
"typedef const char *PCTSTR;"
|
||
|
"typedef char *LPTSTR;"
|
||
|
"typedef char *PTSTR;"
|
||
|
"typedef TBYTE *PTBYTE;"
|
||
|
"typedef TCHAR *PTCHAR;")
|
||
|
self._windows_unicode = enabled_flag
|
||
|
|
||
|
def _apply_windows_unicode(self, kwds):
|
||
|
defmacros = kwds.get('define_macros', ())
|
||
|
if not isinstance(defmacros, (list, tuple)):
|
||
|
raise TypeError("'define_macros' must be a list or tuple")
|
||
|
defmacros = list(defmacros) + [('UNICODE', '1'),
|
||
|
('_UNICODE', '1')]
|
||
|
kwds['define_macros'] = defmacros
|
||
|
|
||
|
def _apply_embedding_fix(self, kwds):
|
||
|
# must include an argument like "-lpython2.7" for the compiler
|
||
|
def ensure(key, value):
|
||
|
lst = kwds.setdefault(key, [])
|
||
|
if value not in lst:
|
||
|
lst.append(value)
|
||
|
#
|
||
|
if '__pypy__' in sys.builtin_module_names:
|
||
|
import os
|
||
|
if sys.platform == "win32":
|
||
|
# we need 'libpypy-c.lib'. Current distributions of
|
||
|
# pypy (>= 4.1) contain it as 'libs/python27.lib'.
|
||
|
pythonlib = "python{0[0]}{0[1]}".format(sys.version_info)
|
||
|
if hasattr(sys, 'prefix'):
|
||
|
ensure('library_dirs', os.path.join(sys.prefix, 'libs'))
|
||
|
else:
|
||
|
# we need 'libpypy-c.{so,dylib}', which should be by
|
||
|
# default located in 'sys.prefix/bin' for installed
|
||
|
# systems.
|
||
|
if sys.version_info < (3,):
|
||
|
pythonlib = "pypy-c"
|
||
|
else:
|
||
|
pythonlib = "pypy3-c"
|
||
|
if hasattr(sys, 'prefix'):
|
||
|
ensure('library_dirs', os.path.join(sys.prefix, 'bin'))
|
||
|
# On uninstalled pypy's, the libpypy-c is typically found in
|
||
|
# .../pypy/goal/.
|
||
|
if hasattr(sys, 'prefix'):
|
||
|
ensure('library_dirs', os.path.join(sys.prefix, 'pypy', 'goal'))
|
||
|
else:
|
||
|
if sys.platform == "win32":
|
||
|
template = "python%d%d"
|
||
|
if hasattr(sys, 'gettotalrefcount'):
|
||
|
template += '_d'
|
||
|
else:
|
||
|
try:
|
||
|
import sysconfig
|
||
|
except ImportError: # 2.6
|
||
|
from cffi._shimmed_dist_utils import sysconfig
|
||
|
template = "python%d.%d"
|
||
|
if sysconfig.get_config_var('DEBUG_EXT'):
|
||
|
template += sysconfig.get_config_var('DEBUG_EXT')
|
||
|
pythonlib = (template %
|
||
|
(sys.hexversion >> 24, (sys.hexversion >> 16) & 0xff))
|
||
|
if hasattr(sys, 'abiflags'):
|
||
|
pythonlib += sys.abiflags
|
||
|
ensure('libraries', pythonlib)
|
||
|
if sys.platform == "win32":
|
||
|
ensure('extra_link_args', '/MANIFEST')
|
||
|
|
||
|
def set_source(self, module_name, source, source_extension='.c', **kwds):
|
||
|
import os
|
||
|
if hasattr(self, '_assigned_source'):
|
||
|
raise ValueError("set_source() cannot be called several times "
|
||
|
"per ffi object")
|
||
|
if not isinstance(module_name, basestring):
|
||
|
raise TypeError("'module_name' must be a string")
|
||
|
if os.sep in module_name or (os.altsep and os.altsep in module_name):
|
||
|
raise ValueError("'module_name' must not contain '/': use a dotted "
|
||
|
"name to make a 'package.module' location")
|
||
|
self._assigned_source = (str(module_name), source,
|
||
|
source_extension, kwds)
|
||
|
|
||
|
def set_source_pkgconfig(self, module_name, pkgconfig_libs, source,
|
||
|
source_extension='.c', **kwds):
|
||
|
from . import pkgconfig
|
||
|
if not isinstance(pkgconfig_libs, list):
|
||
|
raise TypeError("the pkgconfig_libs argument must be a list "
|
||
|
"of package names")
|
||
|
kwds2 = pkgconfig.flags_from_pkgconfig(pkgconfig_libs)
|
||
|
pkgconfig.merge_flags(kwds, kwds2)
|
||
|
self.set_source(module_name, source, source_extension, **kwds)
|
||
|
|
||
|
def distutils_extension(self, tmpdir='build', verbose=True):
|
||
|
from cffi._shimmed_dist_utils import mkpath
|
||
|
from .recompiler import recompile
|
||
|
#
|
||
|
if not hasattr(self, '_assigned_source'):
|
||
|
if hasattr(self, 'verifier'): # fallback, 'tmpdir' ignored
|
||
|
return self.verifier.get_extension()
|
||
|
raise ValueError("set_source() must be called before"
|
||
|
" distutils_extension()")
|
||
|
module_name, source, source_extension, kwds = self._assigned_source
|
||
|
if source is None:
|
||
|
raise TypeError("distutils_extension() is only for C extension "
|
||
|
"modules, not for dlopen()-style pure Python "
|
||
|
"modules")
|
||
|
mkpath(tmpdir)
|
||
|
ext, updated = recompile(self, module_name,
|
||
|
source, tmpdir=tmpdir, extradir=tmpdir,
|
||
|
source_extension=source_extension,
|
||
|
call_c_compiler=False, **kwds)
|
||
|
if verbose:
|
||
|
if updated:
|
||
|
sys.stderr.write("regenerated: %r\n" % (ext.sources[0],))
|
||
|
else:
|
||
|
sys.stderr.write("not modified: %r\n" % (ext.sources[0],))
|
||
|
return ext
|
||
|
|
||
|
def emit_c_code(self, filename):
|
||
|
from .recompiler import recompile
|
||
|
#
|
||
|
if not hasattr(self, '_assigned_source'):
|
||
|
raise ValueError("set_source() must be called before emit_c_code()")
|
||
|
module_name, source, source_extension, kwds = self._assigned_source
|
||
|
if source is None:
|
||
|
raise TypeError("emit_c_code() is only for C extension modules, "
|
||
|
"not for dlopen()-style pure Python modules")
|
||
|
recompile(self, module_name, source,
|
||
|
c_file=filename, call_c_compiler=False, **kwds)
|
||
|
|
||
|
def emit_python_code(self, filename):
|
||
|
from .recompiler import recompile
|
||
|
#
|
||
|
if not hasattr(self, '_assigned_source'):
|
||
|
raise ValueError("set_source() must be called before emit_c_code()")
|
||
|
module_name, source, source_extension, kwds = self._assigned_source
|
||
|
if source is not None:
|
||
|
raise TypeError("emit_python_code() is only for dlopen()-style "
|
||
|
"pure Python modules, not for C extension modules")
|
||
|
recompile(self, module_name, source,
|
||
|
c_file=filename, call_c_compiler=False, **kwds)
|
||
|
|
||
|
def compile(self, tmpdir='.', verbose=0, target=None, debug=None):
|
||
|
"""The 'target' argument gives the final file name of the
|
||
|
compiled DLL. Use '*' to force distutils' choice, suitable for
|
||
|
regular CPython C API modules. Use a file name ending in '.*'
|
||
|
to ask for the system's default extension for dynamic libraries
|
||
|
(.so/.dll/.dylib).
|
||
|
|
||
|
The default is '*' when building a non-embedded C API extension,
|
||
|
and (module_name + '.*') when building an embedded library.
|
||
|
"""
|
||
|
from .recompiler import recompile
|
||
|
#
|
||
|
if not hasattr(self, '_assigned_source'):
|
||
|
raise ValueError("set_source() must be called before compile()")
|
||
|
module_name, source, source_extension, kwds = self._assigned_source
|
||
|
return recompile(self, module_name, source, tmpdir=tmpdir,
|
||
|
target=target, source_extension=source_extension,
|
||
|
compiler_verbose=verbose, debug=debug, **kwds)
|
||
|
|
||
|
def init_once(self, func, tag):
|
||
|
# Read _init_once_cache[tag], which is either (False, lock) if
|
||
|
# we're calling the function now in some thread, or (True, result).
|
||
|
# Don't call setdefault() in most cases, to avoid allocating and
|
||
|
# immediately freeing a lock; but still use setdefaut() to avoid
|
||
|
# races.
|
||
|
try:
|
||
|
x = self._init_once_cache[tag]
|
||
|
except KeyError:
|
||
|
x = self._init_once_cache.setdefault(tag, (False, allocate_lock()))
|
||
|
# Common case: we got (True, result), so we return the result.
|
||
|
if x[0]:
|
||
|
return x[1]
|
||
|
# Else, it's a lock. Acquire it to serialize the following tests.
|
||
|
with x[1]:
|
||
|
# Read again from _init_once_cache the current status.
|
||
|
x = self._init_once_cache[tag]
|
||
|
if x[0]:
|
||
|
return x[1]
|
||
|
# Call the function and store the result back.
|
||
|
result = func()
|
||
|
self._init_once_cache[tag] = (True, result)
|
||
|
return result
|
||
|
|
||
|
def embedding_init_code(self, pysource):
|
||
|
if self._embedding:
|
||
|
raise ValueError("embedding_init_code() can only be called once")
|
||
|
# fix 'pysource' before it gets dumped into the C file:
|
||
|
# - remove empty lines at the beginning, so it starts at "line 1"
|
||
|
# - dedent, if all non-empty lines are indented
|
||
|
# - check for SyntaxErrors
|
||
|
import re
|
||
|
match = re.match(r'\s*\n', pysource)
|
||
|
if match:
|
||
|
pysource = pysource[match.end():]
|
||
|
lines = pysource.splitlines() or ['']
|
||
|
prefix = re.match(r'\s*', lines[0]).group()
|
||
|
for i in range(1, len(lines)):
|
||
|
line = lines[i]
|
||
|
if line.rstrip():
|
||
|
while not line.startswith(prefix):
|
||
|
prefix = prefix[:-1]
|
||
|
i = len(prefix)
|
||
|
lines = [line[i:]+'\n' for line in lines]
|
||
|
pysource = ''.join(lines)
|
||
|
#
|
||
|
compile(pysource, "cffi_init", "exec")
|
||
|
#
|
||
|
self._embedding = pysource
|
||
|
|
||
|
def def_extern(self, *args, **kwds):
|
||
|
raise ValueError("ffi.def_extern() is only available on API-mode FFI "
|
||
|
"objects")
|
||
|
|
||
|
def list_types(self):
|
||
|
"""Returns the user type names known to this FFI instance.
|
||
|
This returns a tuple containing three lists of names:
|
||
|
(typedef_names, names_of_structs, names_of_unions)
|
||
|
"""
|
||
|
typedefs = []
|
||
|
structs = []
|
||
|
unions = []
|
||
|
for key in self._parser._declarations:
|
||
|
if key.startswith('typedef '):
|
||
|
typedefs.append(key[8:])
|
||
|
elif key.startswith('struct '):
|
||
|
structs.append(key[7:])
|
||
|
elif key.startswith('union '):
|
||
|
unions.append(key[6:])
|
||
|
typedefs.sort()
|
||
|
structs.sort()
|
||
|
unions.sort()
|
||
|
return (typedefs, structs, unions)
|
||
|
|
||
|
|
||
|
def _load_backend_lib(backend, name, flags):
|
||
|
import os
|
||
|
if not isinstance(name, basestring):
|
||
|
if sys.platform != "win32" or name is not None:
|
||
|
return backend.load_library(name, flags)
|
||
|
name = "c" # Windows: load_library(None) fails, but this works
|
||
|
# on Python 2 (backward compatibility hack only)
|
||
|
first_error = None
|
||
|
if '.' in name or '/' in name or os.sep in name:
|
||
|
try:
|
||
|
return backend.load_library(name, flags)
|
||
|
except OSError as e:
|
||
|
first_error = e
|
||
|
import ctypes.util
|
||
|
path = ctypes.util.find_library(name)
|
||
|
if path is None:
|
||
|
if name == "c" and sys.platform == "win32" and sys.version_info >= (3,):
|
||
|
raise OSError("dlopen(None) cannot work on Windows for Python 3 "
|
||
|
"(see http://bugs.python.org/issue23606)")
|
||
|
msg = ("ctypes.util.find_library() did not manage "
|
||
|
"to locate a library called %r" % (name,))
|
||
|
if first_error is not None:
|
||
|
msg = "%s. Additionally, %s" % (first_error, msg)
|
||
|
raise OSError(msg)
|
||
|
return backend.load_library(path, flags)
|
||
|
|
||
|
def _make_ffi_library(ffi, libname, flags):
|
||
|
backend = ffi._backend
|
||
|
backendlib = _load_backend_lib(backend, libname, flags)
|
||
|
#
|
||
|
def accessor_function(name):
|
||
|
key = 'function ' + name
|
||
|
tp, _ = ffi._parser._declarations[key]
|
||
|
BType = ffi._get_cached_btype(tp)
|
||
|
value = backendlib.load_function(BType, name)
|
||
|
library.__dict__[name] = value
|
||
|
#
|
||
|
def accessor_variable(name):
|
||
|
key = 'variable ' + name
|
||
|
tp, _ = ffi._parser._declarations[key]
|
||
|
BType = ffi._get_cached_btype(tp)
|
||
|
read_variable = backendlib.read_variable
|
||
|
write_variable = backendlib.write_variable
|
||
|
setattr(FFILibrary, name, property(
|
||
|
lambda self: read_variable(BType, name),
|
||
|
lambda self, value: write_variable(BType, name, value)))
|
||
|
#
|
||
|
def addressof_var(name):
|
||
|
try:
|
||
|
return addr_variables[name]
|
||
|
except KeyError:
|
||
|
with ffi._lock:
|
||
|
if name not in addr_variables:
|
||
|
key = 'variable ' + name
|
||
|
tp, _ = ffi._parser._declarations[key]
|
||
|
BType = ffi._get_cached_btype(tp)
|
||
|
if BType.kind != 'array':
|
||
|
BType = model.pointer_cache(ffi, BType)
|
||
|
p = backendlib.load_function(BType, name)
|
||
|
addr_variables[name] = p
|
||
|
return addr_variables[name]
|
||
|
#
|
||
|
def accessor_constant(name):
|
||
|
raise NotImplementedError("non-integer constant '%s' cannot be "
|
||
|
"accessed from a dlopen() library" % (name,))
|
||
|
#
|
||
|
def accessor_int_constant(name):
|
||
|
library.__dict__[name] = ffi._parser._int_constants[name]
|
||
|
#
|
||
|
accessors = {}
|
||
|
accessors_version = [False]
|
||
|
addr_variables = {}
|
||
|
#
|
||
|
def update_accessors():
|
||
|
if accessors_version[0] is ffi._cdef_version:
|
||
|
return
|
||
|
#
|
||
|
for key, (tp, _) in ffi._parser._declarations.items():
|
||
|
if not isinstance(tp, model.EnumType):
|
||
|
tag, name = key.split(' ', 1)
|
||
|
if tag == 'function':
|
||
|
accessors[name] = accessor_function
|
||
|
elif tag == 'variable':
|
||
|
accessors[name] = accessor_variable
|
||
|
elif tag == 'constant':
|
||
|
accessors[name] = accessor_constant
|
||
|
else:
|
||
|
for i, enumname in enumerate(tp.enumerators):
|
||
|
def accessor_enum(name, tp=tp, i=i):
|
||
|
tp.check_not_partial()
|
||
|
library.__dict__[name] = tp.enumvalues[i]
|
||
|
accessors[enumname] = accessor_enum
|
||
|
for name in ffi._parser._int_constants:
|
||
|
accessors.setdefault(name, accessor_int_constant)
|
||
|
accessors_version[0] = ffi._cdef_version
|
||
|
#
|
||
|
def make_accessor(name):
|
||
|
with ffi._lock:
|
||
|
if name in library.__dict__ or name in FFILibrary.__dict__:
|
||
|
return # added by another thread while waiting for the lock
|
||
|
if name not in accessors:
|
||
|
update_accessors()
|
||
|
if name not in accessors:
|
||
|
raise AttributeError(name)
|
||
|
accessors[name](name)
|
||
|
#
|
||
|
class FFILibrary(object):
|
||
|
def __getattr__(self, name):
|
||
|
make_accessor(name)
|
||
|
return getattr(self, name)
|
||
|
def __setattr__(self, name, value):
|
||
|
try:
|
||
|
property = getattr(self.__class__, name)
|
||
|
except AttributeError:
|
||
|
make_accessor(name)
|
||
|
setattr(self, name, value)
|
||
|
else:
|
||
|
property.__set__(self, value)
|
||
|
def __dir__(self):
|
||
|
with ffi._lock:
|
||
|
update_accessors()
|
||
|
return accessors.keys()
|
||
|
def __addressof__(self, name):
|
||
|
if name in library.__dict__:
|
||
|
return library.__dict__[name]
|
||
|
if name in FFILibrary.__dict__:
|
||
|
return addressof_var(name)
|
||
|
make_accessor(name)
|
||
|
if name in library.__dict__:
|
||
|
return library.__dict__[name]
|
||
|
if name in FFILibrary.__dict__:
|
||
|
return addressof_var(name)
|
||
|
raise AttributeError("cffi library has no function or "
|
||
|
"global variable named '%s'" % (name,))
|
||
|
def __cffi_close__(self):
|
||
|
backendlib.close_lib()
|
||
|
self.__dict__.clear()
|
||
|
#
|
||
|
if isinstance(libname, basestring):
|
||
|
try:
|
||
|
if not isinstance(libname, str): # unicode, on Python 2
|
||
|
libname = libname.encode('utf-8')
|
||
|
FFILibrary.__name__ = 'FFILibrary_%s' % libname
|
||
|
except UnicodeError:
|
||
|
pass
|
||
|
library = FFILibrary()
|
||
|
return library, library.__dict__
|
||
|
|
||
|
def _builtin_function_type(func):
|
||
|
# a hack to make at least ffi.typeof(builtin_function) work,
|
||
|
# if the builtin function was obtained by 'vengine_cpy'.
|
||
|
import sys
|
||
|
try:
|
||
|
module = sys.modules[func.__module__]
|
||
|
ffi = module._cffi_original_ffi
|
||
|
types_of_builtin_funcs = module._cffi_types_of_builtin_funcs
|
||
|
tp = types_of_builtin_funcs[func]
|
||
|
except (KeyError, AttributeError, TypeError):
|
||
|
return None
|
||
|
else:
|
||
|
with ffi._lock:
|
||
|
return ffi._get_cached_btype(tp)
|