source3/python/examples/tdbpack/oldtdbutil.py

   1 #!/usr/bin/python
   2 #############################################################
   3 # tdbutil
   4 #
   5 # Purpose:
   6 #   Contains functions that are used to pack and unpack data
   7 # from Samba's tdb databases.  Samba sometimes represents complex
   8 # data structures as a single value in a database.  These functions
   9 # allow other python scripts to package data types into a single python
  10 # string and unpackage them.
  11 #
  12 #
  13 # XXXXX: This code is no longer used; it's just here for testing
  14 # compatibility with the new (much faster) C implementation.
  15 #
  16 ##############################################################
  17 import string
  18
  19 def pack(format,list):
  20    retstring = ''
  21    listind = 0
  22
  23    # Cycle through format entries
  24    for type in format:
  25       # Null Terminated String
  26       if (type == 'f' or type == 'P'):
  27          retstring = retstring + list[listind] + "\000"
  28       # 4 Byte Number
  29       if (type == 'd'):
  30          retstring = retstring + PackNum(list[listind],4)
  31       # 2 Byte Number
  32       if (type == 'w'):
  33          retstring = retstring + PackNum(list[listind],2)
  34       # Pointer Value
  35       if (type == 'p'):
  36          if (list[listind]):
  37             retstring = retstring + PackNum(1,4)
  38          else:
  39             retstring = retstring + PackNum(0,4)
  40       # Buffer and Length
  41       if (type == 'B'):
  42          # length
  43          length = list[listind]
  44          retstring = retstring + PackNum(length,4)
  45          length = int(length)
  46          listind = listind + 1
  47          # buffer
  48          retstring = retstring + list[listind][:length]
  49
  50       listind = listind + 1
  51
  52    return retstring
  53
  54 def unpack(format,buffer):
  55    retlist = []
  56    bufind = 0
  57
  58    lasttype = ""
  59    for type in format:
  60       # Pointer Value
  61       if (type == 'p'):
  62          newvalue = UnpackNum(buffer[bufind:bufind+4])
  63          bufind = bufind + 4
  64          if (newvalue):
  65             newvalue = 1L
  66          else:
  67             newvalue = 0L
  68          retlist.append(newvalue)
  69       # Previous character till end of data
  70       elif (type == '$'):
  71          if (lasttype == 'f'):
  72             while (bufind < len(buffer)):
  73                newstring = ''
  74                while (buffer[bufind] != '\000'):
  75                   newstring = newstring + buffer[bufind]
  76                   bufind = bufind + 1
  77                bufind = bufind + 1
  78                retlist.append(newstring)
  79       # Null Terminated String
  80       elif (type == 'f' or type == 'P'):
  81          newstring = ''
  82          while (buffer[bufind] != '\000'):
  83             newstring = newstring + buffer[bufind]
  84             bufind = bufind + 1
  85          bufind = bufind + 1
  86          retlist.append(newstring)
  87       # 4 Byte Number
  88       elif (type == 'd'):
  89          newvalue = UnpackNum(buffer[bufind:bufind+4])
  90          bufind = bufind + 4
  91          retlist.append(newvalue)
  92       # 2 Byte Number
  93       elif (type == 'w'):
  94          newvalue = UnpackNum(buffer[bufind:bufind+2])
  95          bufind = bufind + 2
  96          retlist.append(newvalue)
  97       # Length and Buffer
  98       elif (type == 'B'):
  99          # Length
 100          length = UnpackNum(buffer[bufind:bufind+4])
 101          bufind = bufind + 4
 102          retlist.append(length)
 103          length = int(length)
 104          # Buffer
 105          retlist.append(buffer[bufind:bufind+length])
 106          bufind = bufind + length
 107
 108       lasttype = type
 109
 110    return ((retlist,buffer[bufind:]))
 111
 112 def PackNum(myint,size):
 113     retstring = ''
 114     size = size * 2
 115     hint = hex(myint)[2:]
 116
 117     # Check for long notation
 118     if (hint[-1:] == 'L'):
 119        hint = hint[:-1]
 120
 121     addon = size - len(hint)
 122     for i in range(0,addon):
 123        hint = '0' + hint
 124
 125     while (size > 0):
 126        val = string.atoi(hint[size-2:size],16)
 127        retstring = retstring + chr(val)
 128        size = size - 2
 129
 130     return retstring
 131
 132 def UnpackNum(buffer):
 133    size = len(buffer)
 134    mystring = ''
 135
 136    for i in range(size-1,-1,-1):
 137       val = hex(ord(buffer[i]))[2:]
 138       if (len(val) == 1):
 139          val = '0' + val
 140       mystring = mystring + val
 141    if (len(mystring) > 4):
 142       return string.atol(mystring,16)
 143    else:
 144       return string.atoi(mystring,16)