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#
# 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)
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