Actually commit file of byte and hash utilities.

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