ts_102_221: Implement File Descriptor using construct
This automatically adds encoding support, which is needed for upcoming
CREATE FILE support.
Change-Id: Ia40dba4aab6ceb9d81fd170f7efa8dad1f9b43d0
diff --git a/pySim/ts_102_221.py b/pySim/ts_102_221.py
index 82776a0..022a4a7 100644
--- a/pySim/ts_102_221.py
+++ b/pySim/ts_102_221.py
@@ -18,6 +18,7 @@
"""
from construct import *
+from construct import Optional as COptional
from pySim.construct import *
from pySim.utils import *
from pySim.filesystem import *
@@ -87,34 +88,22 @@
# ETSI TS 102 221 11.1.1.4.3
class FileDescriptor(BER_TLV_IE, tag=0x82):
- def _from_bytes(self, in_bin: bytes):
- out = {}
- ft_dict = {
- 0: 'working_ef',
- 1: 'internal_ef',
- 7: 'df'
- }
- fs_dict = {
- 0: 'no_info_given',
- 1: 'transparent',
- 2: 'linear_fixed',
- 6: 'cyclic',
- 0x39: 'ber_tlv',
- }
- fdb = in_bin[0]
- ftype = (fdb >> 3) & 7
- if fdb & 0xbf == 0x39:
- fstruct = 0x39
- else:
- fstruct = fdb & 7
- out['shareable'] = True if fdb & 0x40 else False
- out['file_type'] = ft_dict[ftype] if ftype in ft_dict else ftype
- out['structure'] = fs_dict[fstruct] if fstruct in fs_dict else fstruct
- if len(in_bin) >= 5:
- out['record_len'] = int.from_bytes(in_bin[2:4], 'big')
- out['num_of_rec'] = int.from_bytes(in_bin[4:5], 'big')
- self.decoded = out
- return self.decoded
+ class BerTlvAdapter(Adapter):
+ def _parse(self, obj, context, path):
+ if obj == 0x39:
+ return 'ber_tlv'
+ raise ValidationError
+ def _build(self, obj, context, path):
+ if obj == 'ber_tlv':
+ return 0x39
+ raise ValidationError
+
+ FDB = Select(BitStruct(Const(0, Bit), 'shareable'/Flag, 'structure'/BerTlvAdapter(Const(0x39, BitsInteger(6)))),
+ BitStruct(Const(0, Bit), 'shareable'/Flag, 'file_type'/Enum(BitsInteger(3), working_ef=0, internal_ef=1, df=7),
+ 'structure'/Enum(BitsInteger(3), no_info_given=0, transparent=1, linear_fixed=2, cyclic=6))
+ )
+ _construct = Struct('file_descriptor_byte'/FDB, Const(b'\x21'),
+ 'record_len'/COptional(Int16ub), 'num_of_rec'/COptional(Int16ub))
# ETSI TS 102 221 11.1.1.4.4
class FileIdentifier(BER_TLV_IE, tag=0x83):
@@ -668,7 +657,7 @@
@cmd2.with_argparser(LinFixedEF.ShellCommands.read_recs_dec_parser)
def do_read_arr_records(self, opts):
"""Read + decode all EF.ARR records in flattened, human-friendly form."""
- num_of_rec = self._cmd.rs.selected_file_fcp['file_descriptor']['num_of_rec']
+ num_of_rec = self._cmd.rs.selected_file_num_of_rec()
# collect all results in list so they are rendered as JSON list when printing
data_list = []
for recnr in range(1, 1 + num_of_rec):