--- /dev/null
+"""
+magic is a wrapper around the libmagic file identification library.
+
+See README for more information.
+
+Usage:
+
+>>> from trace_maillog 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'
+>>>
+
+This Python module was taken from: https://github.com/ahupp/python-magic
+
+"""
+
+import sys
+import glob
+import os.path
+import ctypes
+import ctypes.util
+import threading
+
+from ctypes import c_char_p, c_int, c_size_t, c_void_p
+
+
+class MagicException(Exception):
+ def __init__(self, message):
+ super(MagicException, self).__init__(message)
+ self.message = message
+
+
+class Magic:
+ """
+ Magic is a wrapper around the libmagic C library.
+
+ """
+
+ def __init__(self, mime=False, magic_file=None, mime_encoding=False,
+ keep_going=False, uncompress=False):
+ """
+ Create a new libmagic wrapper.
+
+ 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
+ keep_going - don't stop at the first match, keep going
+ uncompress - Try to look inside compressed files.
+ """
+ self.flags = MAGIC_NONE
+ if mime:
+ self.flags |= MAGIC_MIME
+ if mime_encoding:
+ self.flags |= MAGIC_MIME_ENCODING
+ if keep_going:
+ self.flags |= MAGIC_CONTINUE
+
+ if uncompress:
+ self.flags |= MAGIC_COMPRESS
+
+ self.cookie = magic_open(self.flags)
+ self.lock = threading.Lock()
+
+ magic_load(self.cookie, magic_file)
+
+ def from_buffer(self, buf):
+ """
+ Identify the contents of `buf`
+ """
+ with self.lock:
+ try:
+ return maybe_decode(magic_buffer(self.cookie, buf))
+ except MagicException as e:
+ return self._handle509Bug(e)
+
+ def from_file(self, filename):
+ # raise FileNotFoundException or IOError if the file does not exist
+ with open(filename):
+ pass
+ with self.lock:
+ try:
+ return maybe_decode(magic_file(self.cookie, filename))
+ except MagicException as e:
+ return self._handle509Bug(e)
+
+ def _handle509Bug(self, e):
+ # libmagic 5.09 has a bug where it might fail to identify the
+ # mimetype of a file and returns null from magic_file (and
+ # likely _buffer), but also does not return an error message.
+ if e.message is None and (self.flags & MAGIC_MIME):
+ return "application/octet-stream"
+ else:
+ raise e
+
+ def __del__(self):
+ # no _thread_check here because there can be no other
+ # references to this object at this point.
+
+ # during shutdown magic_close may have been cleared already so
+ # make sure it exists before using it.
+
+ # the self.cookie check should be unnecessary and was an
+ # incorrect fix for a threading problem, however I'm leaving
+ # it in because it's harmless and I'm slightly afraid to
+ # remove it.
+ if self.cookie and magic_close:
+ magic_close(self.cookie)
+ self.cookie = None
+
+_instances = {}
+
+def _get_magic_type(mime):
+ i = _instances.get(mime)
+ if i is None:
+ i = _instances[mime] = Magic(mime=mime)
+ return i
+
+def from_file(filename, mime=False):
+ """"
+ Accepts a filename and returns the detected filetype. Return
+ value is the mimetype if mime=True, otherwise a human readable
+ name.
+
+ >>> magic.from_file("testdata/test.pdf", mime=True)
+ 'application/pdf'
+ """
+ m = _get_magic_type(mime)
+ return m.from_file(filename)
+
+def from_buffer(buffer, mime=False):
+ """
+ Accepts a binary string and returns the detected filetype. Return
+ value is the mimetype if mime=True, otherwise a human readable
+ name.
+
+ >>> magic.from_buffer(open("testdata/test.pdf").read(1024))
+ 'PDF document, version 1.2'
+ """
+ m = _get_magic_type(mime)
+ 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') or ctypes.util.find_library('cygmagic-1')
+
+# 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:
+ windows_dlls = ['magic1.dll','cygmagic-1.dll']
+ platform_to_lib = {'darwin': ['/opt/local/lib/libmagic.dylib',
+ '/usr/local/lib/libmagic.dylib'] +
+ # Assumes there will only be one version installed
+ glob.glob('/usr/local/Cellar/libmagic/*/lib/libmagic.dylib'),
+ 'win32': windows_dlls,
+ 'cygwin': windows_dlls,
+ 'linux': ['libmagic.so.1'], # fallback for some Linuxes (e.g. Alpine) where library search does not work
+ }
+ platform = 'linux' if sys.platform.startswith('linux') else sys.platform
+ for dll in platform_to_lib.get(platform, []):
+ try:
+ libmagic = ctypes.CDLL(dll)
+ break
+ 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
+
+def errorcheck_null(result, func, args):
+ if result is None:
+ err = magic_error(args[0])
+ raise MagicException(err)
+ else:
+ return result
+
+def errorcheck_negative_one(result, func, args):
+ if result is -1:
+ err = magic_error(args[0])
+ raise MagicException(err)
+ else:
+ return result
+
+
+# return str on python3. Don't want to unconditionally
+# decode because that results in unicode on python2
+def maybe_decode(s):
+ if str == bytes:
+ return s
+ else:
+ return s.decode('utf-8')
+
+def coerce_filename(filename):
+ if filename is None:
+ return None
+
+ # ctypes will implicitly convert unicode strings to bytes with
+ # .encode('ascii'). If you use the filesystem encoding
+ # then you'll get inconsistent behavior (crashes) depending on the user's
+ # LANG environment variable
+ is_unicode = (sys.version_info[0] <= 2 and
+ isinstance(filename, unicode)) or \
+ (sys.version_info[0] >= 3 and
+ isinstance(filename, str))
+ if is_unicode:
+ return filename.encode('utf-8')
+ else:
+ return filename
+
+magic_open = libmagic.magic_open
+magic_open.restype = magic_t
+magic_open.argtypes = [c_int]
+
+magic_close = libmagic.magic_close
+magic_close.restype = None
+magic_close.argtypes = [magic_t]
+
+magic_error = libmagic.magic_error
+magic_error.restype = c_char_p
+magic_error.argtypes = [magic_t]
+
+magic_errno = libmagic.magic_errno
+magic_errno.restype = c_int
+magic_errno.argtypes = [magic_t]
+
+_magic_file = libmagic.magic_file
+_magic_file.restype = c_char_p
+_magic_file.argtypes = [magic_t, c_char_p]
+_magic_file.errcheck = errorcheck_null
+
+def magic_file(cookie, filename):
+ return _magic_file(cookie, coerce_filename(filename))
+
+_magic_buffer = libmagic.magic_buffer
+_magic_buffer.restype = c_char_p
+_magic_buffer.argtypes = [magic_t, c_void_p, c_size_t]
+_magic_buffer.errcheck = errorcheck_null
+
+def magic_buffer(cookie, buf):
+ return _magic_buffer(cookie, buf, len(buf))
+
+
+_magic_load = libmagic.magic_load
+_magic_load.restype = c_int
+_magic_load.argtypes = [magic_t, c_char_p]
+_magic_load.errcheck = errorcheck_negative_one
+
+def magic_load(cookie, filename):
+ return _magic_load(cookie, coerce_filename(filename))
+
+magic_setflags = libmagic.magic_setflags
+magic_setflags.restype = c_int
+magic_setflags.argtypes = [magic_t, c_int]
+
+magic_check = libmagic.magic_check
+magic_check.restype = c_int
+magic_check.argtypes = [magic_t, c_char_p]
+
+magic_compile = libmagic.magic_compile
+magic_compile.restype = c_int
+magic_compile.argtypes = [magic_t, c_char_p]
+
+
+
+MAGIC_NONE = 0x000000 # No flags
+MAGIC_DEBUG = 0x000001 # Turn on debugging
+MAGIC_SYMLINK = 0x000002 # Follow symlinks
+MAGIC_COMPRESS = 0x000004 # Check inside compressed files
+MAGIC_DEVICES = 0x000008 # Look at the contents of devices
+MAGIC_MIME = 0x000010 # Return a mime string
+MAGIC_MIME_ENCODING = 0x000400 # Return the MIME encoding
+MAGIC_CONTINUE = 0x000020 # Return all matches
+MAGIC_CHECK = 0x000040 # Print warnings to stderr
+MAGIC_PRESERVE_ATIME = 0x000080 # Restore access time on exit
+MAGIC_RAW = 0x000100 # Don't translate unprintable chars
+MAGIC_ERROR = 0x000200 # Handle ENOENT etc as real errors
+
+MAGIC_NO_CHECK_COMPRESS = 0x001000 # Don't check for compressed files
+MAGIC_NO_CHECK_TAR = 0x002000 # Don't check for tar files
+MAGIC_NO_CHECK_SOFT = 0x004000 # Don't check magic entries
+MAGIC_NO_CHECK_APPTYPE = 0x008000 # Don't check application type
+MAGIC_NO_CHECK_ELF = 0x010000 # Don't check for elf details
+MAGIC_NO_CHECK_ASCII = 0x020000 # Don't check for ascii files
+MAGIC_NO_CHECK_TROFF = 0x040000 # Don't check ascii/troff
+MAGIC_NO_CHECK_FORTRAN = 0x080000 # Don't check ascii/fortran
+MAGIC_NO_CHECK_TOKENS = 0x100000 # Don't check ascii/tokens
projects / pixelpark / trace-maillog.git / commitdiff