twisted/conch/ssh/sexpy.py

   1 # Copyright (c) Twisted Matrix Laboratories.
   2 # See LICENSE for details.
   3
   4 #
   5
   6 def parse(s):
   7     s = s.strip()
   8     expr = []
   9     while s:
  10         if s[0] == '(':
  11             newSexp = []
  12             if expr:
  13                 expr[-1].append(newSexp)
  14             expr.append(newSexp)
  15             s = s[1:]
  16             continue
  17         if s[0] == ')':
  18             aList = expr.pop()
  19             s=s[1:]
  20             if not expr:
  21                 assert not s
  22                 return aList
  23             continue
  24         i = 0
  25         while s[i].isdigit(): i+=1
  26         assert i
  27         length = int(s[:i])
  28         data = s[i+1:i+1+length]
  29         expr[-1].append(data)
  30         s=s[i+1+length:]
  31     assert 0, "this should not happen"
  32
  33 def pack(sexp):
  34     s = ""
  35     for o in sexp:
  36         if type(o) in (type(()), type([])):
  37             s+='('
  38             s+=pack(o)
  39             s+=')'
  40         else:
  41             s+='%i:%s' % (len(o), o)
  42     return s