mdw@git.distorted.org.uk Git - catacomb/blob - utils/split-pieces

   1 #! /usr/bin/python
   2
   3 from sys import argv, exit
   4 from itertools import cycle, izip
   5 import re as RX
   6
   7 def bad_usage():
   8   exit('usage: split-pieces { scaf WD | qf P WD/N|WD,WD,... } N N ...')
   9
  10 ARGC = 1
  11 def getarg(must = True):
  12   global ARGC
  13   if ARGC < len(argv): ARGC += 1; return argv[ARGC - 1]
  14   elif must: bad_usage()
  15   else: return None
  16
  17 class ScafConvert (object):
  18   def __init__(me, piecewd):
  19     me.piecewd = piecewd
  20     me.fmt = '0x%%0%dx' % ((piecewd + 3)/4)
  21     me.mask = (1 << piecewd) - 1
  22   @classmethod
  23   def parse(cls):
  24     return ScafConvert(int(getarg()))
  25   def hack(me, n):
  26     nn = []
  27     while n:
  28       nn.append(me.fmt % (n&me.mask))
  29       n >>= me.piecewd
  30     return nn
  31   def unhack(me, nn):
  32     return sum(n << i*me.piecewd for i, n in enumerate(nn))
  33
  34 class BaseQfConvert (object):
  35   def __init__(me, p, wdseq):
  36     me.p = p
  37     me.wdseq = wdseq
  38   @classmethod
  39   def parse(cls):
  40     p = eval(getarg())
  41     arg = getarg()
  42     if '/' in arg:
  43       wd, n = map(int, arg.split('/'))
  44       seq = [(wd*(i + 1) + n - 1)/n - (wd*i + n - 1)/n for i in xrange(n)]
  45     else:
  46       seq = map(int, arg.split(','))
  47     print ";; piece widths = %r" % seq
  48     return cls(p, seq)
  49   def hack(me, n):
  50     if me.SIGNEDP and 2*n >= me.p: n -= me.p
  51     nn = []
  52     wds = cycle(me.wdseq)
  53     while n:
  54       wd = wds.next()
  55       lim = 1 << wd; m = lim - 1
  56       d = n&m; n >>= wd
  57       if me.SIGNEDP and d >= lim/2: d -= lim; n += 1
  58       nn.append(me.fmt(d))
  59     return nn
  60   def unhack(me, nn):
  61     a = o = 0
  62     for n, w in izip(nn, cycle(me.wdseq)):
  63       a += n << o
  64       o += w
  65     if a < 0: a += me.p
  66     return a
  67
  68 class SignedQfConvert (BaseQfConvert):
  69   SIGNEDP = True
  70   def fmt(me, n): return str(n)
  71
  72 class UnsignedQfConvert (BaseQfConvert):
  73   SIGNEDP = False
  74   def fmt(me, n): return '0x%x' % n
  75
  76 R_split = RX.compile(r',\s*|\s+')
  77 def spliteval(arg): return map(eval, R_split.split(arg.strip()))
  78
  79 convmap = { 'scaf': ScafConvert,
  80             'unscaf': ScafConvert,
  81             'qf': SignedQfConvert,
  82             'unqf': SignedQfConvert,
  83             'uqf': UnsignedQfConvert,
  84             'unuqf': UnsignedQfConvert }
  85 op = getarg()
  86 cvt = convmap[op].parse()
  87 if op.startswith('un'): prepare, conv, format = spliteval, cvt.unhack, str
  88 else: prepare, conv, format = eval, cvt.hack, lambda vv: ', '.join(vv)
  89
  90 while True:
  91   val = getarg(must = False)
  92   if val is None: break
  93   print format(conv(prepare(val)))