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 414b2e57..4beb6ffd 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): |