3 files changed, 73 insertions, 60 deletions

diff --git a/glucometerutils/drivers/otultraeasy.py b/glucometerutils/drivers/otultraeasy.py
index 57c7ea2..0063ec1 100644
--- a/glucometerutils/drivers/otultraeasy.py
+++ b/glucometerutils/drivers/otultraeasy.py
@@ -15,7 +15,7 @@ Expected device path: /dev/ttyUSB0 or similar serial port device.
 
 __author__ = 'Diego Elio Pettenò'
 __email__ = 'flameeyes@flameeyes.eu'
-__copyright__ = 'Copyright © 2014-2017, Diego Elio Pettenò'
+__copyright__ = 'Copyright © 2014-2018, Diego Elio Pettenò'
 __license__ = 'MIT'
 
 import binascii
@@ -27,36 +27,12 @@ import construct
 from glucometerutils import common
 from glucometerutils.support import construct_extras
 from glucometerutils.support import lifescan
+from glucometerutils.support import lifescan_binary_protocol
 from glucometerutils.support import serial
 
 
 _INVALID_RECORD = 501
 
-
-_PACKET = construct.Struct(
-    construct.RawCopy(
-        construct.Embedded(
-            construct.Struct(
-                construct.Const(b'\x02'),  # stx
-                'length' / construct.Rebuild(
-                    construct.Byte, lambda ctx: len(ctx.message) + 6),
-                construct.EmbeddedBitStruct(
-                    construct.Padding(3),
-                    'more' / construct.Default(construct.Flag, False),
-                    'disconnect' / construct.Flag,
-                    'acknowledge' / construct.Flag,
-                    'expect_receive' / construct.Flag,
-                    'sequence_number' / construct.Flag,
-                ),
-                'message' / construct.Bytes(length=lambda ctx: ctx.length - 6),
-                construct.Const(b'\x03'),  # etx
-            ),
-        ),
-    ),
-    'checksum' / construct.Checksum(
-        construct.Int16ul, lifescan.crc_ccitt, construct.this.data),
-)
-
 _COMMAND_SUCCESS = construct.Const(b'\x05\x06')
 
 _VERSION_REQUEST = construct.Const(b'\x05\x0d\x02')
@@ -130,7 +106,8 @@ class Device(serial.SerialDevice):
 
         self.sent_counter_ = False
         self.expect_receive_ = False
-        self.buffered_reader_ = construct.Rebuffered(_PACKET, tailcutoff=1024)
+        self.buffered_reader_ = construct.Rebuffered(
+            lifescan_binary_protocol.PACKET, tailcutoff=1024)
 
     def connect(self):
         try:
@@ -143,13 +120,15 @@ class Device(serial.SerialDevice):
         self.connect()
 
     def _send_packet(self, message, acknowledge=False, disconnect=False):
-        pkt = _PACKET.build(
+        pkt = lifescan_binary_protocol.PACKET.build(
             {'value': {
                 'message': message,
-                'sequence_number': self.sent_counter_,
-                'expect_receive': self.expect_receive_,
-                'acknowledge': acknowledge,
-                'disconnect': disconnect,
+                'link_control': {
+                    'sequence_number': self.sent_counter_,
+                    'expect_receive': self.expect_receive_,
+                    'acknowledge': acknowledge,
+                    'disconnect': disconnect,
+                },
             }})
         logging.debug('sending packet: %s', binascii.hexlify(pkt))
 
diff --git a/glucometerutils/drivers/otverio2015.py b/glucometerutils/drivers/otverio2015.py
index 2c5b52f..d0b8a9c 100644
--- a/glucometerutils/drivers/otverio2015.py
+++ b/glucometerutils/drivers/otverio2015.py
@@ -22,7 +22,7 @@ https://flameeyes.github.io/glucometer-protocols/lifescan/onetouch-verio-2015
 
 __author__ = 'Diego Elio Pettenò'
 __email__ = 'flameeyes@flameeyes.eu'
-__copyright__ = 'Copyright © 2016-2017, Diego Elio Pettenò'
+__copyright__ = 'Copyright © 2016-2018, Diego Elio Pettenò'
 __license__ = 'MIT'
 
 import binascii
@@ -35,38 +35,17 @@ from pyscsi.pyscsi.scsi_device import SCSIDevice
 
 from glucometerutils import common
 from glucometerutils import exceptions
-from glucometerutils.support import construct_extras
 from glucometerutils.support import lifescan
+from glucometerutils.support import lifescan_binary_protocol
 
 # This device uses SCSI blocks as registers.
 _REGISTER_SIZE = 512
 
 _PACKET = construct.Padded(
-    512, construct.Struct(
-        construct.RawCopy(
-            construct.Embedded(
-                construct.Struct(
-                    construct.Const(b'\x02'),  # stx
-                    'length' / construct.Rebuild(
-                        construct.Int16ul, lambda ctx: len(ctx.message) + 6),
-                    'message' / construct.Bytes(
-                        length=lambda ctx: ctx.length - 6),
-                    construct.Const(b'\x03'),  # etx
-                ),
-            ),
-        ),
-        'checksum' / construct.Checksum(
-            construct.Int16ul, lifescan.crc_ccitt, construct.this.data),
-    ),
-)
+    _REGISTER_SIZE, construct.Embedded(lifescan_binary_protocol.PACKET))
 
 _COMMAND_SUCCESS = construct.Const(b'\x04\x06')
 
-# Device-specific timestamp. All timestamp reported by this device are seconds
-# since this date.
-_TIMESTAMP = construct_extras.Timestamp(
-    construct.Int32ul, epoch=946684800)  # 2010-01-01 00:00
-
 _QUERY_REQUEST = construct.Struct(
     construct.Const(b'\x04\xe6\x02'),
     'selector' / construct.Enum(
@@ -101,12 +80,12 @@ _READ_RTC_REQUEST = construct.Const(b'\x04\x20\x02')
 
 _READ_RTC_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
-    'timestamp' / _TIMESTAMP,
+    'timestamp' / lifescan_binary_protocol.VERIO_TIMESTAMP,
 )
 
 _WRITE_RTC_REQUEST = construct.Struct(
     construct.Const(b'\x04\x20\x01'),
-    'timestamp' / _TIMESTAMP,
+    'timestamp' / lifescan_binary_protocol.VERIO_TIMESTAMP,
 )
 
 _MEMORY_ERASE_REQUEST = construct.Const(b'\x04\x1a')
@@ -135,7 +114,7 @@ _READ_RECORD_RESPONSE = construct.Struct(
     'inverse_counter' / construct.Int16ul,
     construct.Padding(1),
     'lifetime_counter' / construct.Int16ul,
-    'timestamp' / _TIMESTAMP,
+    'timestamp' / lifescan_binary_protocol.VERIO_TIMESTAMP,
     'value' / construct.Int16ul,
     'meal' / construct.SymmetricMapping(
         construct.Byte, _MEAL_FLAG),
@@ -186,7 +165,10 @@ class Device(object):
         """
         try:
             request = request_format.build(request_obj)
-            request_raw = _PACKET.build({'value': {'message': request}})
+            request_raw = _PACKET.build({'value': {
+                'message': request,
+                'link_control': {},  # Verio does not use link_control.
+            }})
             logging.debug(
                 'Request sent: %s', binascii.hexlify(request_raw))
             self.scsi_.write10(lba, 1, request_raw)
diff --git a/glucometerutils/support/lifescan_binary_protocol.py b/glucometerutils/support/lifescan_binary_protocol.py
new file mode 100644
index 0000000..68b030d
--- /dev/null
+++ b/glucometerutils/support/lifescan_binary_protocol.py
@@ -0,0 +1,52 @@
+# -*- coding: utf-8 -*-
+"""Support module for the LifeScan binary protocol.
+
+A number of LifeScan devices use a semi-compatible binary protocol to talk host
+and device, which is (vastly) compatible.
+
+This module implements an interface to send and receive these messages.
+"""
+
+__author__ = 'Diego Elio Pettenò'
+__email__ = 'flameeyes@flameeyes.eu'
+__copyright__ = 'Copyright © 2014-2018, Diego Elio Pettenò'
+__license__ = 'MIT'
+
+import construct
+
+from glucometerutils.support import construct_extras
+from glucometerutils.support import lifescan
+
+
+PACKET = construct.Struct(
+    construct.RawCopy(
+        construct.Embedded(
+            construct.Struct(
+                construct.Const(b'\x02'),  # stx
+                'length' / construct.Rebuild(
+                    construct.Byte, lambda ctx: len(ctx.message) + 6),
+                # The following structure is only used by some of the devices.
+                'link_control' / construct.BitStruct(
+                    construct.Padding(3),
+                    'more' / construct.Default(
+                        construct.Flag, False),
+                    'disconnect' / construct.Default(
+                        construct.Flag, False),
+                    'acknowledge' / construct.Default(
+                        construct.Flag, False),
+                    'expect_receive' / construct.Default(
+                        construct.Flag, False),
+                    'sequence_number' / construct.Default(
+                        construct.Flag, False),
+                ),
+                'message' / construct.Bytes(length=lambda ctx: ctx.length - 6),
+                construct.Const(b'\x03'),  # etx
+            ),
+        ),
+    ),
+    'checksum' / construct.Checksum(
+        construct.Int16ul, lifescan.crc_ccitt, construct.this.data),
+)
+
+VERIO_TIMESTAMP = construct_extras.Timestamp(
+    construct.Int32ul, epoch=946684800)  # 2010-01-01 00:00