diff options
Diffstat (limited to 'cffi/verifier.py')
| -rw-r--r-- | cffi/verifier.py | 306 |
1 files changed, 306 insertions, 0 deletions
diff --git a/cffi/verifier.py b/cffi/verifier.py new file mode 100644 index 0000000..59b78c2 --- /dev/null +++ b/cffi/verifier.py @@ -0,0 +1,306 @@ +# +# DEPRECATED: implementation for ffi.verify() +# +import sys, os, binascii, shutil, io +from . import __version_verifier_modules__ +from . import ffiplatform +from .error import VerificationError + +if sys.version_info >= (3, 3): + import importlib.machinery + def _extension_suffixes(): + return importlib.machinery.EXTENSION_SUFFIXES[:] +else: + import imp + def _extension_suffixes(): + return [suffix for suffix, _, type in imp.get_suffixes() + if type == imp.C_EXTENSION] + + +if sys.version_info >= (3,): + NativeIO = io.StringIO +else: + class NativeIO(io.BytesIO): + def write(self, s): + if isinstance(s, unicode): + s = s.encode('ascii') + super(NativeIO, self).write(s) + + +class Verifier(object): + + def __init__(self, ffi, preamble, tmpdir=None, modulename=None, + ext_package=None, tag='', force_generic_engine=False, + source_extension='.c', flags=None, relative_to=None, **kwds): + if ffi._parser._uses_new_feature: + raise VerificationError( + "feature not supported with ffi.verify(), but only " + "with ffi.set_source(): %s" % (ffi._parser._uses_new_feature,)) + self.ffi = ffi + self.preamble = preamble + if not modulename: + flattened_kwds = ffiplatform.flatten(kwds) + vengine_class = _locate_engine_class(ffi, force_generic_engine) + self._vengine = vengine_class(self) + self._vengine.patch_extension_kwds(kwds) + self.flags = flags + self.kwds = self.make_relative_to(kwds, relative_to) + # + if modulename: + if tag: + raise TypeError("can't specify both 'modulename' and 'tag'") + else: + key = '\x00'.join([sys.version[:3], __version_verifier_modules__, + preamble, flattened_kwds] + + ffi._cdefsources) + if sys.version_info >= (3,): + key = key.encode('utf-8') + k1 = hex(binascii.crc32(key[0::2]) & 0xffffffff) + k1 = k1.lstrip('0x').rstrip('L') + k2 = hex(binascii.crc32(key[1::2]) & 0xffffffff) + k2 = k2.lstrip('0').rstrip('L') + modulename = '_cffi_%s_%s%s%s' % (tag, self._vengine._class_key, + k1, k2) + suffix = _get_so_suffixes()[0] + self.tmpdir = tmpdir or _caller_dir_pycache() + self.sourcefilename = os.path.join(self.tmpdir, modulename + source_extension) + self.modulefilename = os.path.join(self.tmpdir, modulename + suffix) + self.ext_package = ext_package + self._has_source = False + self._has_module = False + + def write_source(self, file=None): + """Write the C source code. It is produced in 'self.sourcefilename', + which can be tweaked beforehand.""" + with self.ffi._lock: + if self._has_source and file is None: + raise VerificationError( + "source code already written") + self._write_source(file) + + def compile_module(self): + """Write the C source code (if not done already) and compile it. + This produces a dynamic link library in 'self.modulefilename'.""" + with self.ffi._lock: + if self._has_module: + raise VerificationError("module already compiled") + if not self._has_source: + self._write_source() + self._compile_module() + + def load_library(self): + """Get a C module from this Verifier instance. + Returns an instance of a FFILibrary class that behaves like the + objects returned by ffi.dlopen(), but that delegates all + operations to the C module. If necessary, the C code is written + and compiled first. + """ + with self.ffi._lock: + if not self._has_module: + self._locate_module() + if not self._has_module: + if not self._has_source: + self._write_source() + self._compile_module() + return self._load_library() + + def get_module_name(self): + basename = os.path.basename(self.modulefilename) + # kill both the .so extension and the other .'s, as introduced + # by Python 3: 'basename.cpython-33m.so' + basename = basename.split('.', 1)[0] + # and the _d added in Python 2 debug builds --- but try to be + # conservative and not kill a legitimate _d + if basename.endswith('_d') and hasattr(sys, 'gettotalrefcount'): + basename = basename[:-2] + return basename + + def get_extension(self): + ffiplatform._hack_at_distutils() # backward compatibility hack + if not self._has_source: + with self.ffi._lock: + if not self._has_source: + self._write_source() + sourcename = ffiplatform.maybe_relative_path(self.sourcefilename) + modname = self.get_module_name() + return ffiplatform.get_extension(sourcename, modname, **self.kwds) + + def generates_python_module(self): + return self._vengine._gen_python_module + + def make_relative_to(self, kwds, relative_to): + if relative_to and os.path.dirname(relative_to): + dirname = os.path.dirname(relative_to) + kwds = kwds.copy() + for key in ffiplatform.LIST_OF_FILE_NAMES: + if key in kwds: + lst = kwds[key] + if not isinstance(lst, (list, tuple)): + raise TypeError("keyword '%s' should be a list or tuple" + % (key,)) + lst = [os.path.join(dirname, fn) for fn in lst] + kwds[key] = lst + return kwds + + # ---------- + + def _locate_module(self): + if not os.path.isfile(self.modulefilename): + if self.ext_package: + try: + pkg = __import__(self.ext_package, None, None, ['__doc__']) + except ImportError: + return # cannot import the package itself, give up + # (e.g. it might be called differently before installation) + path = pkg.__path__ + else: + path = None + filename = self._vengine.find_module(self.get_module_name(), path, + _get_so_suffixes()) + if filename is None: + return + self.modulefilename = filename + self._vengine.collect_types() + self._has_module = True + + def _write_source_to(self, file): + self._vengine._f = file + try: + self._vengine.write_source_to_f() + finally: + del self._vengine._f + + def _write_source(self, file=None): + if file is not None: + self._write_source_to(file) + else: + # Write our source file to an in memory file. + f = NativeIO() + self._write_source_to(f) + source_data = f.getvalue() + + # Determine if this matches the current file + if os.path.exists(self.sourcefilename): + with open(self.sourcefilename, "r") as fp: + needs_written = not (fp.read() == source_data) + else: + needs_written = True + + # Actually write the file out if it doesn't match + if needs_written: + _ensure_dir(self.sourcefilename) + with open(self.sourcefilename, "w") as fp: + fp.write(source_data) + + # Set this flag + self._has_source = True + + def _compile_module(self): + # compile this C source + tmpdir = os.path.dirname(self.sourcefilename) + outputfilename = ffiplatform.compile(tmpdir, self.get_extension()) + try: + same = ffiplatform.samefile(outputfilename, self.modulefilename) + except OSError: + same = False + if not same: + _ensure_dir(self.modulefilename) + shutil.move(outputfilename, self.modulefilename) + self._has_module = True + + def _load_library(self): + assert self._has_module + if self.flags is not None: + return self._vengine.load_library(self.flags) + else: + return self._vengine.load_library() + +# ____________________________________________________________ + +_FORCE_GENERIC_ENGINE = False # for tests + +def _locate_engine_class(ffi, force_generic_engine): + if _FORCE_GENERIC_ENGINE: + force_generic_engine = True + if not force_generic_engine: + if '__pypy__' in sys.builtin_module_names: + force_generic_engine = True + else: + try: + import _cffi_backend + except ImportError: + _cffi_backend = '?' + if ffi._backend is not _cffi_backend: + force_generic_engine = True + if force_generic_engine: + from . import vengine_gen + return vengine_gen.VGenericEngine + else: + from . import vengine_cpy + return vengine_cpy.VCPythonEngine + +# ____________________________________________________________ + +_TMPDIR = None + +def _caller_dir_pycache(): + if _TMPDIR: + return _TMPDIR + result = os.environ.get('CFFI_TMPDIR') + if result: + return result + filename = sys._getframe(2).f_code.co_filename + return os.path.abspath(os.path.join(os.path.dirname(filename), + '__pycache__')) + +def set_tmpdir(dirname): + """Set the temporary directory to use instead of __pycache__.""" + global _TMPDIR + _TMPDIR = dirname + +def cleanup_tmpdir(tmpdir=None, keep_so=False): + """Clean up the temporary directory by removing all files in it + called `_cffi_*.{c,so}` as well as the `build` subdirectory.""" + tmpdir = tmpdir or _caller_dir_pycache() + try: + filelist = os.listdir(tmpdir) + except OSError: + return + if keep_so: + suffix = '.c' # only remove .c files + else: + suffix = _get_so_suffixes()[0].lower() + for fn in filelist: + if fn.lower().startswith('_cffi_') and ( + fn.lower().endswith(suffix) or fn.lower().endswith('.c')): + try: + os.unlink(os.path.join(tmpdir, fn)) + except OSError: + pass + clean_dir = [os.path.join(tmpdir, 'build')] + for dir in clean_dir: + try: + for fn in os.listdir(dir): + fn = os.path.join(dir, fn) + if os.path.isdir(fn): + clean_dir.append(fn) + else: + os.unlink(fn) + except OSError: + pass + +def _get_so_suffixes(): + suffixes = _extension_suffixes() + if not suffixes: + # bah, no C_EXTENSION available. Occurs on pypy without cpyext + if sys.platform == 'win32': + suffixes = [".pyd"] + else: + suffixes = [".so"] + + return suffixes + +def _ensure_dir(filename): + dirname = os.path.dirname(filename) + if dirname and not os.path.isdir(dirname): + os.makedirs(dirname) |