From 8742a56b3ed87c2ba6bd67400c1044256dd5578b Mon Sep 17 00:00:00 2001 From: Lance Stout Date: Mon, 30 Jul 2012 19:29:33 -0700 Subject: Actually commit file of byte and hash utilities. --- sleekxmpp/util/misc_ops.py | 122 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 sleekxmpp/util/misc_ops.py diff --git a/sleekxmpp/util/misc_ops.py b/sleekxmpp/util/misc_ops.py new file mode 100644 index 00000000..9ed535d9 --- /dev/null +++ b/sleekxmpp/util/misc_ops.py @@ -0,0 +1,122 @@ +import sys +import hashlib + + +def unicode(text): + if sys.version_info < (3, 0): + import __builtin__ + return __builtin__.unicode(text) + return str(text) + + +def bytes(text): + """ + Convert Unicode text to UTF-8 encoded bytes. + + Since Python 2.6+ and Python 3+ have similar but incompatible + signatures, this function unifies the two to keep code sane. + + :param text: Unicode text to convert to bytes + :rtype: bytes (Python3), str (Python2.6+) + """ + if sys.version_info < (3, 0): + import __builtin__ + return __builtin__.bytes(text) + else: + import builtins + if isinstance(text, builtins.bytes): + # We already have bytes, so do nothing + return text + if isinstance(text, list): + # Convert a list of integers to bytes + return builtins.bytes(text) + else: + # Convert UTF-8 text to bytes + return builtins.bytes(text, encoding='utf-8') + + +def quote(text): + """ + Enclose in quotes and escape internal slashes and double quotes. + + :param text: A Unicode or byte string. + """ + text = bytes(text) + return b'"' + text.replace(b'\\', b'\\\\').replace(b'"', b'\\"') + b'"' + + +def num_to_bytes(num): + """ + Convert an integer into a four byte sequence. + + :param integer num: An integer to convert to its byte representation. + """ + bval = b'' + bval += bytes(chr(0xFF & (num >> 24))) + bval += bytes(chr(0xFF & (num >> 16))) + bval += bytes(chr(0xFF & (num >> 8))) + bval += bytes(chr(0xFF & (num >> 0))) + return bval + + +def bytes_to_num(bval): + """ + Convert a four byte sequence to an integer. + + :param bytes bval: A four byte sequence to turn into an integer. + """ + num = 0 + num += ord(bval[0] << 24) + num += ord(bval[1] << 16) + num += ord(bval[2] << 8) + num += ord(bval[3]) + return num + + +def XOR(x, y): + """ + Return the results of an XOR operation on two equal length byte strings. + + :param bytes x: A byte string + :param bytes y: A byte string + :rtype: bytes + """ + result = b'' + for a, b in zip(x, y): + if sys.version_info < (3, 0): + result += chr((ord(a) ^ ord(b))) + else: + result += bytes([a ^ b]) + return result + + +def hash(name): + """ + Return a hash function implementing the given algorithm. + + :param name: The name of the hashing algorithm to use. + :type name: string + + :rtype: function + """ + name = name.lower() + if name.startswith('sha-'): + name = 'sha' + name[4:] + if name in dir(hashlib): + return getattr(hashlib, name) + return None + + +def hashes(): + """ + Return a list of available hashing algorithms. + + :rtype: list of strings + """ + t = [] + if 'md5' in dir(hashlib): + t = ['MD5'] + if 'md2' in dir(hashlib): + t += ['MD2'] + hashes = ['SHA-' + h[3:] for h in dir(hashlib) if h.startswith('sha')] + return t + hashes -- cgit v1.2.3