openmedialibrary_platform/Linux_i686/lib/python2.7/site-packages/cffi/verifier.py
2014-05-17 18:11:40 +00:00

243 lines
8.6 KiB
Python

import sys, os, binascii, imp, shutil
from . import __version__
from . import ffiplatform
class Verifier(object):
def __init__(self, ffi, preamble, tmpdir=None, modulename=None,
ext_package=None, tag='', force_generic_engine=False, **kwds):
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.kwds = kwds
#
if modulename:
if tag:
raise TypeError("can't specify both 'modulename' and 'tag'")
else:
key = '\x00'.join([sys.version[:3], __version__, 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 + '.c')
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 ffiplatform.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 ffiplatform.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):
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 _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(self, file=None):
must_close = (file is None)
if must_close:
_ensure_dir(self.sourcefilename)
file = open(self.sourcefilename, 'w')
self._vengine._f = file
try:
self._vengine.write_source_to_f()
finally:
del self._vengine._f
if must_close:
file.close()
if must_close:
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
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
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 = []
for suffix, mode, type in imp.get_suffixes():
if type == imp.C_EXTENSION:
suffixes.append(suffix)
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):
try:
os.makedirs(os.path.dirname(filename))
except OSError:
pass