|
Description:
Simple routine for dumping any kind of string, ascii, encoded, or unicode, to a standard hex dump. Plus read/write of unicode and encoded strings.
Source: Text Source
"""
UnicodeHexDump.py
Simple routine for dumping any kind of string, ascii, encoded, or
unicode, to a standard hex dump.
Also two simple routines for reading and writing unicode strings
as encoded strings in a file.
Based on ASPN: Hex dumper -- Sebastien Keim & Raymond Hettinger
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/142812
Jack Trainor 2008
"""
""" dump any string to formatted hex output """
def dump(s):
import types
if type(s) == types.StringType:
return dumpString(s)
elif type(s) == types.UnicodeType:
return dumpUnicodeString(s)
FILTER = ''.join([(len(repr(chr(x))) == 3) and chr(x) or '.' for x in range(256)])
""" dump any string, ascii or encoded, to formatted hex output """
def dumpString(src, length=16):
result = []
for i in xrange(0, len(src), length):
chars = src[i:i+length]
hex = ' '.join(["%02x" % ord(x) for x in chars])
printable = ''.join(["%s" % ((ord(x) <= 127 and FILTER[ord(x)]) or '.') for x in chars])
result.append("%04x %-*s %s\n" % (i, length*3, hex, printable))
return ''.join(result)
""" dump unicode string to formatted hex output """
def dumpUnicodeString(src, length=8):
result = []
for i in xrange(0, len(src), length):
unichars = src[i:i+length]
hex = ' '.join(["%04x" % ord(x) for x in unichars])
printable = ''.join(["%s" % ((ord(x) <= 127 and FILTER[ord(x)]) or '.') for x in unichars])
result.append("%04x %-*s %s\n" % (i*2, length*5, hex, printable))
return ''.join(result)
""" read unicode string from encoded file """
def readFile(path, encoding, errors="replace"):
raw = open(path, 'rb').read()
uniText = raw.decode(encoding, errors)
return uniText
""" write unicode string to encoded file """
def writeFile(path, uniText, encoding, errors="replace"):
encText = uniText.encode(encoding, errors)
open(path, 'wb').write(encText)
def test():
TEST = u"Copyright: \u00a9\r\nRegistered: \u00ae\r\nAlpha: \u03b1\r\nOmega: \u03c9\r\n\Em dash: \u2015\r\n"
print dump("ascii " + TEST.encode("ascii", "replace"))
print dump("Latin-1 " + TEST.encode("Latin-1", "replace"))
print dump("utf8 " + TEST.encode("utf8", "replace"))
print dump("utf16 " + TEST.encode("utf16", "replace"))
print dump("utf-16-be " + TEST.encode("utf-16-be", "replace"))
print dump("utf-16-le " + TEST.encode("utf-16-le", "replace"))
print dump("unicode " + TEST)
DELETE_ME_TXT = "deleteme.txt"
writeFile(DELETE_ME_TXT, TEST, "utf8")
uniText = readFile(DELETE_ME_TXT, "utf8")
assert (uniText == TEST)
if __name__ == "__main__":
test()
Discussion:
Sometimes when I am working with encoded strings I want to touch bottom with the underlying hex so I know exactly what I am looking at--especially handy for learning the ins and outs of unicode and encoded strings in Python.
When I was learning unicode, I searched the Python documentation and the web for code samples and I was confused by how many ways there were to handle unicode and encoded strings, but the basics are really very simple: just use encode() and decode().
Hat tip to Sebastien Keim & Raymond Hettinger
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/142812
|
