utilities.py

import struct

def readLogFile(filename, verbose=True):
  
  f = open(filename, 'rb')

  print('Opened'),
  print(filename)

  keys = f.readline().decode('utf8').rstrip('\n').split(',')
  fmt = f.readline().decode('utf8').rstrip('\n')

  # The byte number of one record
  sz = struct.calcsize(fmt)
  # The type number of one record
  ncols = len(fmt)

  if verbose:
    print('Keys:'),
    print(keys)
    print('Format:'),
    print(fmt)
    print('Size:'),
    print(sz)
    print('Columns:'),
    print(ncols)

  lenChunk = sz
  log = list()
  chunkIndex = 0
  while (lenChunk):
    check = f.read(2)
    lenChunk = 0
    if (check == b'\xaa\xbb'):
      mychunk = f.read(sz)
      lenChunk = len(mychunk)
      chunks = [mychunk]
      if verbose:
        print("num chunks:")
        print(len(chunks))

      for chunk in chunks:
        print("len(chunk)=", len(chunk), " sz = ", sz)
        if len(chunk) == sz:
          print("chunk #", chunkIndex)
          chunkIndex = chunkIndex + 1
          values = struct.unpack(fmt, chunk)
          record = list()
          for i in range(ncols):
            record.append(values[i])
            if verbose:
              print("    ", keys[i], "=", values[i])

          log.append(record)
    else:
      print("Error, expected aabb terminal")
  return log