Esempio n. 1
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 def __init__(self, parent, name, nbytes,
 description="Padding", pattern=None):
     """ pattern is None or repeated string """
     assert (pattern is None) or (isinstance(pattern, str))
     Bytes.__init__(self, parent, name, nbytes, description)
     self.pattern = pattern
     self._display_pattern = self.checkPattern()
Esempio n. 2
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 def __init__(self,
              parent,
              name,
              nbytes,
              description="Padding",
              pattern=None):
     """ pattern is None or repeated string """
     assert (pattern is None) or (isinstance(pattern, str))
     Bytes.__init__(self, parent, name, nbytes, description)
     self.pattern = pattern
     self._display_pattern = self.checkPattern()
Esempio n. 3
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 def __init__(self, parent, name, length, description=None,
 parser=None, filename=None, mime_type=None, parser_class=None):
     if filename:
         if not isinstance(filename, unicode):
             filename = makePrintable(filename, "ISO-8859-1")
         if not description:
             description = 'File "%s" (%s)' % (filename, humanFilesize(length))
     Bytes.__init__(self, parent, name, length, description)
     def createInputStream(cis, **args):
         tags = args.setdefault("tags",[])
         if parser_class:
             tags.append(( "class", parser_class ))
         if parser is not None:
             tags.append(( "id", parser.PARSER_TAGS["id"] ))
         if mime_type:
             tags.append(( "mime", mime_type ))
         if filename:
             tags.append(( "filename", filename ))
         return cis(**args)
     self.setSubIStream(createInputStream)
Esempio n. 4
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    def __init__(self, parent, name, format, description=None,
    strip=None, charset=None, nbytes=None, truncate=None):
        Bytes.__init__(self, parent, name, 1, description)

        # Is format valid?
        assert format in self.VALID_FORMATS

        # Store options
        self._format = format
        self._strip = strip
        self._truncate = truncate

        # Check charset and compute character size in bytes
        # (or None when it's not possible to guess character size)
        if not charset or charset in self.CHARSET_8BIT:
            self._character_size = 1   # one byte per character
        elif charset in self.UTF_CHARSET:
            self._character_size = None
        else:
            raise FieldError("Invalid charset for %s: \"%s\"" %
                (self.path, charset))
        self._charset = charset

        # It is a fixed string?
        if nbytes is not None:
            assert self._format == "fixed"
            # Arbitrary limits, just to catch some bugs...
            if not (1 <= nbytes <= 0xffff):
                raise FieldError("Invalid string size for %s: %s" %
                    (self.path, nbytes))
            self._content_size = nbytes   # content length in bytes
            self._size = nbytes * 8
            self._content_offset = 0
        else:
            # Format with a suffix: Find the end of the string
            if self._format in self.SUFFIX_FORMAT:
                self._content_offset = 0

                # Choose the suffix
                suffix = self.suffix_str

                # Find the suffix
                length = self._parent.stream.searchBytesLength(
                    suffix, False, self.absolute_address)
                if length is None:
                    raise FieldError("Unable to find end of string %s (format %s)!"
                        % (self.path, self._format))
                if 1 < len(suffix):
                    # Fix length for little endian bug with UTF-xx charset:
                    #   u"abc" -> "a\0b\0c\0\0\0" (UTF-16-LE)
                    #   search returns length=5, whereas real lenght is 6
                    length = alignValue(length, len(suffix))

                # Compute sizes
                self._content_size = length # in bytes
                self._size = (length + len(suffix)) * 8

            # Format with a prefix: Read prefixed length in bytes
            else:
                assert self._format in self.PASCAL_FORMATS

                # Get the prefix size
                prefix_size = self.PASCAL_FORMATS[self._format]
                self._content_offset = prefix_size

                # Read the prefix and compute sizes
                value = self._parent.stream.readBits(
                    self.absolute_address, prefix_size*8, self._parent.endian)
                self._content_size = value   # in bytes
                self._size = (prefix_size + value) * 8

        # For UTF-16 and UTF-32, choose the right charset using BOM
        if self._charset in self.UTF_CHARSET:
            # Charset requires a BOM?
            bomsize, endian  = self.UTF_CHARSET[self._charset]
            if endian == "BOM":
                # Read the BOM value
                nbytes = bomsize // 8
                bom = self._parent.stream.readBytes(self.absolute_address, nbytes)

                # Choose right charset using the BOM
                bom_endian = self.UTF_BOM[bomsize]
                if bom not in bom_endian:
                    raise FieldError("String %s has invalid BOM (%s)!"
                        % (self.path, repr(bom)))
                self._charset = bom_endian[bom]
                self._content_size -= nbytes
                self._content_offset += nbytes

        # Compute length in character if possible
        if self._character_size:
            self._length = self._content_size //  self._character_size
        else:
            self._length = None
Esempio n. 5
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 def __init__(self, parent):
     Bytes.__init__(self, parent, 'file', parent['size'].value, None)
Esempio n. 6
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    def __init__(self,
                 parent,
                 name,
                 format,
                 description=None,
                 strip=None,
                 charset=None,
                 nbytes=None,
                 truncate=None):
        Bytes.__init__(self, parent, name, 1, description)

        # Is format valid?
        assert format in self.VALID_FORMATS

        # Store options
        self._format = format
        self._strip = strip
        self._truncate = truncate

        # Check charset and compute character size in bytes
        # (or None when it's not possible to guess character size)
        if not charset or charset in self.CHARSET_8BIT:
            self._character_size = 1  # one byte per character
        elif charset in self.UTF_CHARSET:
            self._character_size = None
        else:
            raise FieldError("Invalid charset for %s: \"%s\"" %
                             (self.path, charset))
        self._charset = charset

        # It is a fixed string?
        if nbytes is not None:
            assert self._format == "fixed"
            # Arbitrary limits, just to catch some bugs...
            if not (1 <= nbytes <= 0xffff):
                raise FieldError("Invalid string size for %s: %s" %
                                 (self.path, nbytes))
            self._content_size = nbytes  # content length in bytes
            self._size = nbytes * 8
            self._content_offset = 0
        else:
            # Format with a suffix: Find the end of the string
            if self._format in self.SUFFIX_FORMAT:
                self._content_offset = 0

                # Choose the suffix
                suffix = self.suffix_str

                # Find the suffix
                length = self._parent.stream.searchBytesLength(
                    suffix, False, self.absolute_address)
                if length is None:
                    raise FieldError(
                        "Unable to find end of string %s (format %s)!" %
                        (self.path, self._format))
                if 1 < len(suffix):
                    # Fix length for little endian bug with UTF-xx charset:
                    #   u"abc" -> "a\0b\0c\0\0\0" (UTF-16-LE)
                    #   search returns length=5, whereas real lenght is 6
                    length = alignValue(length, len(suffix))

                # Compute sizes
                self._content_size = length  # in bytes
                self._size = (length + len(suffix)) * 8

            # Format with a prefix: Read prefixed length in bytes
            else:
                assert self._format in self.PASCAL_FORMATS

                # Get the prefix size
                prefix_size = self.PASCAL_FORMATS[self._format]
                self._content_offset = prefix_size

                # Read the prefix and compute sizes
                value = self._parent.stream.readBits(self.absolute_address,
                                                     prefix_size * 8,
                                                     self._parent.endian)
                self._content_size = value  # in bytes
                self._size = (prefix_size + value) * 8

        # For UTF-16 and UTF-32, choose the right charset using BOM
        if self._charset in self.UTF_CHARSET:
            # Charset requires a BOM?
            bomsize, endian = self.UTF_CHARSET[self._charset]
            if endian == "BOM":
                # Read the BOM value
                nbytes = bomsize // 8
                bom = self._parent.stream.readBytes(self.absolute_address,
                                                    nbytes)

                # Choose right charset using the BOM
                bom_endian = self.UTF_BOM[bomsize]
                if bom not in bom_endian:
                    raise FieldError("String %s has invalid BOM (%s)!" %
                                     (self.path, repr(bom)))
                self._charset = bom_endian[bom]
                self._content_size -= nbytes
                self._content_offset += nbytes

        # Compute length in character if possible
        if self._character_size:
            self._length = self._content_size // self._character_size
        else:
            self._length = None
Esempio n. 7
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 def __init__(self, parent, name):
     Bytes.__init__(self, parent, name, 16)