updated third-party magic library

This commit is contained in:
Bernardo Damele 2012-12-18 23:58:49 +00:00
parent 9e2f0131b9
commit aeda67e945

View File

@ -1,13 +1,23 @@
#!/usr/bin/env python """
magic is a wrapper around the libmagic file identification library.
See README for more information.
Usage:
>>> import magic
>>> magic.from_file("testdata/test.pdf")
'PDF document, version 1.2'
>>> magic.from_file("testdata/test.pdf", mime=True)
'application/pdf'
>>> magic.from_buffer(open("testdata/test.pdf").read(1024))
'PDF document, version 1.2'
>>>
"""
Adam Hupp <adam@hupp.org>
Reference: http://hupp.org/adam/hg/python-magic
License: PSF (http://www.python.org/psf/license/)
""" """
import sys
import os.path import os.path
import ctypes import ctypes
import ctypes.util import ctypes.util
@ -22,22 +32,26 @@ class Magic:
""" """
def __init__(self, mime=False, magic_file=None): def __init__(self, mime=False, magic_file=None, mime_encoding=False):
""" """
Create a new libmagic wrapper. Create a new libmagic wrapper.
mime - if True, mimetypes are returned instead of textual descriptions mime - if True, mimetypes are returned instead of textual descriptions
mime_encoding - if True, codec is returned
magic_file - use a mime database other than the system default magic_file - use a mime database other than the system default
""" """
flags = MAGIC_NONE flags = MAGIC_NONE
if mime: if mime:
flags |= MAGIC_MIME flags |= MAGIC_MIME
elif mime_encoding:
flags |= MAGIC_MIME_ENCODING
self.cookie = magic_open(flags) self.cookie = magic_open(flags)
magic_load(self.cookie, magic_file) magic_load(self.cookie, magic_file)
def from_buffer(self, buf): def from_buffer(self, buf):
""" """
Identify the contents of `buf` Identify the contents of `buf`
@ -56,10 +70,10 @@ class Magic:
return magic_file(self.cookie, filename) return magic_file(self.cookie, filename)
def __del__(self): def __del__(self):
try: # during shutdown magic_close may have been cleared already
if self.cookie and magic_close:
magic_close(self.cookie) magic_close(self.cookie)
except Exception, _: self.cookie = None
pass
_magic_mime = None _magic_mime = None
_magic = None _magic = None
@ -90,8 +104,32 @@ def from_buffer(buffer, mime=False):
m = _get_magic_type(mime) m = _get_magic_type(mime)
return m.from_buffer(buffer) return m.from_buffer(buffer)
libmagic = None
# Let's try to find magic or magic1
dll = ctypes.util.find_library('magic') or ctypes.util.find_library('magic1')
# This is necessary because find_library returns None if it doesn't find the library
if dll:
libmagic = ctypes.CDLL(dll)
if not libmagic or not libmagic._name:
import sys
platform_to_lib = {'darwin': ['/opt/local/lib/libmagic.dylib',
'/usr/local/lib/libmagic.dylib',
'/usr/local/Cellar/libmagic/5.10/lib/libmagic.dylib'],
'win32': ['magic1.dll']}
for dll in platform_to_lib.get(sys.platform, []):
try: try:
libmagic = ctypes.CDLL(ctypes.util.find_library('magic')) libmagic = ctypes.CDLL(dll)
except OSError:
pass
if not libmagic or not libmagic._name:
# It is better to raise an ImportError since we are importing magic module
raise ImportError('failed to find libmagic. Check your installation')
magic_t = ctypes.c_void_p magic_t = ctypes.c_void_p
@ -102,6 +140,11 @@ try:
else: else:
return result return result
def coerce_filename(filename):
if filename is None:
return None
return filename.encode(sys.getfilesystemencoding())
magic_open = libmagic.magic_open magic_open = libmagic.magic_open
magic_open.restype = magic_t magic_open.restype = magic_t
magic_open.argtypes = [c_int] magic_open.argtypes = [c_int]
@ -109,7 +152,6 @@ try:
magic_close = libmagic.magic_close magic_close = libmagic.magic_close
magic_close.restype = None magic_close.restype = None
magic_close.argtypes = [magic_t] magic_close.argtypes = [magic_t]
magic_close.errcheck = errorcheck
magic_error = libmagic.magic_error magic_error = libmagic.magic_error
magic_error.restype = c_char_p magic_error.restype = c_char_p
@ -119,23 +161,31 @@ try:
magic_errno.restype = c_int magic_errno.restype = c_int
magic_errno.argtypes = [magic_t] magic_errno.argtypes = [magic_t]
magic_file = libmagic.magic_file _magic_file = libmagic.magic_file
magic_file.restype = c_char_p _magic_file.restype = c_char_p
magic_file.argtypes = [magic_t, c_char_p] _magic_file.argtypes = [magic_t, c_char_p]
magic_file.errcheck = errorcheck _magic_file.errcheck = errorcheck
def magic_file(cookie, filename):
return _magic_file(cookie, coerce_filename(filename))
_magic_buffer = libmagic.magic_buffer _magic_buffer = libmagic.magic_buffer
_magic_buffer.restype = c_char_p _magic_buffer.restype = c_char_p
_magic_buffer.argtypes = [magic_t, c_void_p, c_size_t] _magic_buffer.argtypes = [magic_t, c_void_p, c_size_t]
_magic_buffer.errcheck = errorcheck _magic_buffer.errcheck = errorcheck
def magic_buffer(cookie, buf): def magic_buffer(cookie, buf):
return _magic_buffer(cookie, buf, len(buf)) return _magic_buffer(cookie, buf, len(buf))
magic_load = libmagic.magic_load
magic_load.restype = c_int _magic_load = libmagic.magic_load
magic_load.argtypes = [magic_t, c_char_p] _magic_load.restype = c_int
magic_load.errcheck = errorcheck _magic_load.argtypes = [magic_t, c_char_p]
_magic_load.errcheck = errorcheck
def magic_load(cookie, filename):
return _magic_load(cookie, coerce_filename(filename))
magic_setflags = libmagic.magic_setflags magic_setflags = libmagic.magic_setflags
magic_setflags.restype = c_int magic_setflags.restype = c_int
@ -148,8 +198,8 @@ try:
magic_compile = libmagic.magic_compile magic_compile = libmagic.magic_compile
magic_compile.restype = c_int magic_compile.restype = c_int
magic_compile.argtypes = [magic_t, c_char_p] magic_compile.argtypes = [magic_t, c_char_p]
except:
pass
MAGIC_NONE = 0x000000 # No flags MAGIC_NONE = 0x000000 # No flags
@ -163,6 +213,8 @@ MAGIC_DEVICES = 0x000008 # Look at the contents of devices
MAGIC_MIME = 0x000010 # Return a mime string MAGIC_MIME = 0x000010 # Return a mime string
MAGIC_MIME_ENCODING = 0x000400 # Return the MIME encoding
MAGIC_CONTINUE = 0x000020 # Return all matches MAGIC_CONTINUE = 0x000020 # Return all matches
MAGIC_CHECK = 0x000040 # Print warnings to stderr MAGIC_CHECK = 0x000040 # Print warnings to stderr