diff options
Diffstat (limited to 'netlib')
| -rw-r--r-- | netlib/strutils.py | 80 | ||||
| -rw-r--r-- | netlib/websockets/frame.py | 2 | 
2 files changed, 53 insertions, 29 deletions
diff --git a/netlib/strutils.py b/netlib/strutils.py index cfcdf485..809f5e17 100644 --- a/netlib/strutils.py +++ b/netlib/strutils.py @@ -1,4 +1,4 @@ -import unicodedata +import re  import codecs  import six @@ -28,51 +28,71 @@ def native(s, *encoding_opts):      return s -def clean_bin(s, keep_spacing=True): -    # type: (Union[bytes, six.text_type], bool) -> six.text_type +# Translate control characters to "safe" characters. This implementation initially +# replaced them with the matching control pictures (http://unicode.org/charts/PDF/U2400.pdf), +# but that turned out to render badly with monospace fonts. We are back to "." therefore. +_control_char_trans = { +    x: ord(".")  # x + 0x2400 for unicode control group pictures +    for x in range(32) +} +_control_char_trans[127] = ord(".")  # 0x2421 +_control_char_trans_newline = _control_char_trans.copy() +for x in ("\r", "\n", "\t"): +    del _control_char_trans_newline[ord(x)] + + +if six.PY2: +    pass +else: +    _control_char_trans = str.maketrans(_control_char_trans) +    _control_char_trans_newline = str.maketrans(_control_char_trans_newline) + + +def escape_control_characters(text, keep_spacing=True):      """ -        Cleans binary data to make it safe to display. +    Replace all unicode C1 control characters from the given text with their respective control pictures. +    For example, a null byte is replaced with the unicode character "\u2400". -        Args: -            keep_spacing: If False, tabs and newlines will also be replaced. +    Args: +        keep_spacing: If True, tabs and newlines will not be replaced.      """ -    if isinstance(s, six.text_type): -        if keep_spacing: -            keep = u" \n\r\t" -        else: -            keep = u" " +    # type: (six.text_type) -> six.text_type +    if not isinstance(text, six.text_type): +        raise ValueError("text type must be unicode but is {}".format(type(text).__name__)) + +    trans = _control_char_trans_newline if keep_spacing else _control_char_trans +    if six.PY2:          return u"".join( -            ch if (unicodedata.category(ch)[0] not in "CZ" or ch in keep) else u"." -            for ch in s -        ) -    else: -        if keep_spacing: -            keep = (9, 10, 13)  # \t, \n, \r, -        else: -            keep = () -        return "".join( -            chr(ch) if (31 < ch < 127 or ch in keep) else "." -            for ch in six.iterbytes(s) +            six.unichr(trans.get(ord(ch), ord(ch))) +            for ch in text          ) +    return text.translate(trans) -def bytes_to_escaped_str(data): +def bytes_to_escaped_str(data, keep_spacing=False):      """      Take bytes and return a safe string that can be displayed to the user.      Single quotes are always escaped, double quotes are never escaped:          "'" + bytes_to_escaped_str(...) + "'"      gives a valid Python string. + +    Args: +        keep_spacing: If True, tabs and newlines will not be escaped.      """ -    # TODO: We may want to support multi-byte characters without escaping them. -    # One way to do would be calling .decode("utf8", "backslashreplace") first -    # and then escaping UTF8 control chars (see clean_bin).      if not isinstance(data, bytes):          raise ValueError("data must be bytes, but is {}".format(data.__class__.__name__))      # We always insert a double-quote here so that we get a single-quoted string back      # https://stackoverflow.com/questions/29019340/why-does-python-use-different-quotes-for-representing-strings-depending-on-their -    return repr(b'"' + data).lstrip("b")[2:-1] +    ret = repr(b'"' + data).lstrip("b")[2:-1] +    if keep_spacing: +        ret = re.sub( +            r"(?<!\\)(\\\\)*\\([nrt])", +            lambda m: (m.group(1) or "") + dict(n="\n", r="\r", t="\t")[m.group(2)], +            ret +        ) +    return ret  def escaped_str_to_bytes(data): @@ -136,4 +156,8 @@ def hexdump(s):          part = s[i:i + 16]          x = " ".join("{:0=2x}".format(i) for i in six.iterbytes(part))          x = x.ljust(47)  # 16*2 + 15 -        yield (offset, x, clean_bin(part, False)) +        part_repr = escape_control_characters( +            part.decode("ascii", "replace").replace(u"\ufffd", u"."), +            False +        ) +        yield (offset, x, part_repr) diff --git a/netlib/websockets/frame.py b/netlib/websockets/frame.py index 671e1605..7d355699 100644 --- a/netlib/websockets/frame.py +++ b/netlib/websockets/frame.py @@ -255,7 +255,7 @@ class Frame(object):      def __repr__(self):          ret = repr(self.header)          if self.payload: -            ret = ret + "\nPayload:\n" + strutils.clean_bin(self.payload) +            ret = ret + "\nPayload:\n" + strutils.bytes_to_escaped_str(self.payload)          return ret      def human_readable(self):  | 
