Example #1
0
 def unpack_number(self):
     # variable length numbers, MSB first, 7 bits per byte, last byte is
     # flagged by MSB set
     raw = self.buffer[self.offset:self.offset + 10]
     number, consumed = decint(raw)
     self.advance(consumed)
     return number
Example #2
0
 def unpack_number(self):
     # variable length numbers, MSB first, 7 bits per byte, last byte is
     # flagged by MSB set
     raw = self.buffer[self.offset:self.offset+10]
     number, consumed = decint(raw)
     self.advance(consumed)
     return number
Example #3
0
 def __init__(self, records, codec):
     self.records = OrderedDict()
     record_offset = 0
     for raw in records:
         pos = 0
         while pos < len(raw):
             length, consumed = decint(raw[pos:])
             if length > 0:
                 try:
                     self.records[pos+record_offset] = raw[
                         pos+consumed:pos+consumed+length].decode(codec)
                 except:
                     byts = raw[pos:]
                     r = format_bytes(byts)
                     print ('CNCX entry at offset %d has unknown format %s'%(
                         pos+record_offset, r))
                     self.records[pos+record_offset] = r
                     pos = len(raw)
             pos += consumed+length
         record_offset += 0x10000
Example #4
0
 def __init__(self, records, codec):
     self.records = OrderedDict()
     record_offset = 0
     for raw in records:
         pos = 0
         while pos < len(raw):
             length, consumed = decint(raw[pos:])
             if length > 0:
                 try:
                     self.records[pos+record_offset] = raw[
                         pos+consumed:pos+consumed+length].decode(codec)
                 except:
                     byts = raw[pos:]
                     r = format_bytes(byts)
                     print ('CNCX entry at offset %d has unknown format %s'%(
                         pos+record_offset, r))
                     self.records[pos+record_offset] = r
                     pos = len(raw)
             pos += consumed+length
         record_offset += 0x10000
Example #5
0
def get_tag_map(control_byte_count, tagx, data, strict=False):
    ptags = []
    ans = {}
    control_bytes = list(bytearray(data[:control_byte_count]))
    data = data[control_byte_count:]

    for x in tagx:
        if x.eof == 0x01:
            control_bytes = control_bytes[1:]
            continue
        value = control_bytes[0] & x.bitmask
        if value != 0:
            value_count = value_bytes = None
            if value == x.bitmask:
                if count_set_bits(x.bitmask) > 1:
                    # If all bits of masked value are set and the mask has more
                    # than one bit, a variable width value will follow after
                    # the control bytes which defines the length of bytes (NOT
                    # the value count!) which will contain the corresponding
                    # variable width values.
                    value_bytes, consumed = decint(data)
                    data = data[consumed:]
                else:
                    value_count = 1
            else:
                # Shift bits to get the masked value.
                mask = x.bitmask
                while mask & 0b1 == 0:
                    mask >>= 1
                    value >>= 1
                value_count = value
            ptags.append(
                PTagX(x.tag, value_count, value_bytes, x.num_of_values))

    for x in ptags:
        values = []
        if x.value_count is not None:
            # Read value_count * values_per_entry variable width values.
            for _ in xrange(x.value_count * x.num_of_values):
                byts, consumed = decint(data)
                data = data[consumed:]
                values.append(byts)
        else:  # value_bytes is not None
            # Convert value_bytes to variable width values.
            total_consumed = 0
            while total_consumed < x.value_bytes:
                # Does this work for values_per_entry != 1?
                byts, consumed = decint(data)
                data = data[consumed:]
                total_consumed += consumed
                values.append(byts)
            if total_consumed != x.value_bytes:
                err = ("Error: Should consume %s bytes, but consumed %s" %
                       (x.value_bytes, total_consumed))
                if strict:
                    raise ValueError(err)
                else:
                    print(err)
        ans[x.tag] = values
    # Test that all bytes have been processed
    if data.replace(b'\0', b''):
        err = ("Warning: There are unprocessed index bytes left: %s" %
               format_bytes(data))
        if strict:
            raise ValueError(err)
        else:
            print(err)

    return ans
Example #6
0
def get_tag_map(control_byte_count, tagx, data, strict=False):
    ptags = []
    ans = {}
    control_bytes = list(bytearray(data[:control_byte_count]))
    data = data[control_byte_count:]

    for x in tagx:
        if x.eof == 0x01:
            control_bytes = control_bytes[1:]
            continue
        value = control_bytes[0] & x.bitmask
        if value != 0:
            value_count = value_bytes = None
            if value == x.bitmask:
                if count_set_bits(x.bitmask) > 1:
                    # If all bits of masked value are set and the mask has more
                    # than one bit, a variable width value will follow after
                    # the control bytes which defines the length of bytes (NOT
                    # the value count!) which will contain the corresponding
                    # variable width values.
                    value_bytes, consumed = decint(data)
                    data = data[consumed:]
                else:
                    value_count = 1
            else:
                # Shift bits to get the masked value.
                mask = x.bitmask
                while mask & 0b1 == 0:
                    mask >>= 1
                    value >>= 1
                value_count = value
            ptags.append(PTagX(x.tag, value_count, value_bytes,
                x.num_of_values))

    for x in ptags:
        values = []
        if x.value_count is not None:
            # Read value_count * values_per_entry variable width values.
            for _ in xrange(x.value_count * x.num_of_values):
                byts, consumed = decint(data)
                data = data[consumed:]
                values.append(byts)
        else: # value_bytes is not None
            # Convert value_bytes to variable width values.
            total_consumed = 0
            while total_consumed < x.value_bytes:
                # Does this work for values_per_entry != 1?
                byts, consumed = decint(data)
                data = data[consumed:]
                total_consumed += consumed
                values.append(byts)
            if total_consumed != x.value_bytes:
                err = ("Error: Should consume %s bytes, but consumed %s" %
                        (x.value_bytes, total_consumed))
                if strict:
                    raise ValueError(err)
                else:
                    print(err)
        ans[x.tag] = values
    # Test that all bytes have been processed
    if data.replace(b'\0', b''):
        err = ("Warning: There are unprocessed index bytes left: %s" %
                format_bytes(data))
        if strict:
            raise ValueError(err)
        else:
            print(err)

    return ans