dwlib.py

def canonicalize(instr):
    outt = []
    npos = pos = 0
    while pos <= len(instr):
        npos += 8
        s = instr[pos:npos]
        if not s:
            break
        hs = ''
        cs = ''
        for c in s:
            n = ord(c)
            hs += "%02x" % n
            cs += c if 32 < n < 127 else '.'
        outt.append((pos, hs, cs))
        pos = npos

    # print outt
    outh = outc = ''
    ostr = ["len: %s" % len(instr)]
    eight = sixteen = ppos = 0
    state = 0
    for pos, h, c in outt:
        outh += "%-16s" % h
        outc += "%-8s" % c
        eight = (pos % 8) == 0
        sixteen = (pos % 16) == 0

        if state == 0:
            ppos = pos
            outh += ' '
            outc += ' '
            state = 1
        elif state == 1:
            ostr.append("%04x: |%s| |%s|" % (ppos, outh, outc))
            outh = outc = ''
            state = 0
        # print pos, eight, sixteen
        # if eight and not sixteen:
        # 	outh += ' '
        # 	outc += ' '
        # if sixteen:
        # 	ppos = pos
        # if pos>0 and sixteen:
        # 	ostr.append("%04x: |%s| |%s|" % (ppos, outh, outc))
        # 	outh = outc = ''

    # print pos, outc, outh
    # if pos==0 or (eight and not sixteen):
    # if len(outc)<0:
    if len(instr) == 0:
        ostr.append("%04x: |%s| |%s|" % (ppos, ' ' * 33, ' ' * 17))
    elif state == 1:
        ostr.append(
            "%04x: |%s                | |%s        |" %
            (ppos, outh, outc))
        outh = outc = ''
    return '\n'.join(ostr)


def hexscii(s):
    d = ''
    sl = len(s)
    p = 0
    while p < sl:
        e = p + 2
        d += chr(int(s[p:e], 16))
        p = e
    return d


if __name__ == '__main__':
    strs = [
        '',
        'a',
        'a' * 8,
        'a' * 9,
        'a' * 16,
        'a' * 17,
        'a' * 23,
        'a' * 24,
        'a' * 31,
        'a' * 32,
    ]

    for s in strs:
        print "==="
        print canonicalize(s)


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