Mavgen WLua: Handle multiplier attribute in XML parser

Mavparse: Handle attribute and store it in the internal classes

Mavgen WLua: Handle multiplier when displaying in Wireshark
Add a test case to demonstrate the behaviour
Remove unused uses of mavlink_type in Python code

generator/mavgen_wlua.py

@@ -47,6 +47,12 @@ def get_field_info(field):
         field_type = "ftypes." + mavlink_type.upper()
         tvb_func = "le_" + mavlink_type
 
+    # If a multiplier is defined, then add this to the displayed mavlink type
+    # and set the field type to DOUBLE to ensure that the full number is shown
+    if field.multiplier != "":
+        mavlink_type = mavlink_type + "*" + field.multiplier
+        field_type = "ftypes.DOUBLE"
+
     return mavlink_type, field_type, tvb_func, size, count
 
 
@@ -222,7 +228,7 @@ def generate_msg_fields(outf, msg, enums):
                 index_text = ''
 
             name = t.substitute("${fmsg}_${fname}${findex}", {'fmsg':msg.name, 'fname':f.name, 'findex':index_text})
-            label = t.substitute("${fname}${farray}", {'fname':f.name, 'farray':array_text, 'ftypename': mavlink_type})
+            label = t.substitute("${fname}${farray}", {'fname':f.name, 'farray':array_text})
             generate_field_or_param(outf, f, name, label, mavlink_type, field_type, enums)
 
     t.write(outf, '\n\n')
@@ -287,7 +293,7 @@ def generate_field_dissector(outf, msg, field, offset, enums, cmd=None, param=No
     assert cmd is None or isinstance(cmd, mavparse.MAVEnumEntry)
     assert param is None or isinstance(param, mavparse.MAVEnumParam)
 
-    mavlink_type, _, tvb_func, size, count = get_field_info(field)
+    _, _, tvb_func, size, count = get_field_info(field)
 
     enum_name = param.enum if param else field.enum
     enum_obj = enum_name and next((e for e in enums if e.name == enum_name), None)
@@ -319,6 +325,14 @@ def generate_field_dissector(outf, msg, field, offset, enums, cmd=None, param=No
     value = tvbrange:${ftvbfunc}()
     subtree = tree:add_le(f.${fvar}, tvbrange, value)
 """, {'foffset': offset + i * size, 'fbytes': size, 'ftvbfunc': tvb_func, 'fvar': field_var})
+        elif field.multiplier != "":
+            value_extracted = True
+            t.write(outf,
+"""
+    tvbrange = padded(offset + ${foffset}, ${fbytes})
+    value = tvbrange:${ftvbfunc}() * ${mult}
+    subtree = tree:add_le(f.${fvar}, tvbrange, value)
+""", {'foffset': offset + i * size, 'fbytes': size, 'ftvbfunc': tvb_func, 'fvar': field_var, 'mult': field.multiplier})
         else:
             value_extracted = False
             t.write(outf,

generator/mavparse.py

@@ -33,14 +33,15 @@ def __str__(self):
         return self.message
 
 class MAVField(object):
-    def __init__(self, name, type, print_format, xml, description='', enum='', display='', units='', instance=False):
+    def __init__(self, name, type, print_format, xml, description='', enum='', display='', units='', multiplier='', instance=False):
         self.name = name
         self.name_upper = name.upper()
         self.description = description
         self.array_length = 0
         self.enum = enum
         self.display = display
         self.units = units
+        self.multiplier = multiplier
         self.omit_arg = False
         self.const_value = None
         self.print_format = print_format
@@ -141,7 +142,7 @@ def base_fields(self):
         return len(self.fields[:self.extensions_start])
 
 class MAVEnumParam(object):
-    def __init__(self, index, description='', label='', units='', enum='', increment='', minValue='', maxValue='', reserved=False, default=''):
+    def __init__(self, index, description='', label='', units='', enum='', increment='', minValue='', maxValue='', reserved=False, default='', multiplier=''):
         self.index = index
         self.description = description
         self.label = label
@@ -152,6 +153,7 @@ def __init__(self, index, description='', label='', units='', enum='', increment
         self.maxValue = maxValue
         self.reserved = reserved
         self.default = default
+        self.multiplier = multiplier
         if self.reserved and not self.default:
             self.default = '0'
         self.set_description(description)
@@ -256,8 +258,9 @@ def start_element(name, attrs):
                 units = attrs.get('units', '')
                 if units:
                     units = '[' + units + ']'
+                multiplier = attrs.get('multiplier', '')
                 instance = attrs.get('instance', False)
-                new_field = MAVField(attrs['name'], attrs['type'], print_format, self, enum=enum, display=display, units=units, instance=instance)
+                new_field = MAVField(attrs['name'], attrs['type'], print_format, self, enum=enum, display=display, units=units, multiplier=multiplier, instance=instance)
                 if self.message[-1].extensions_start is None or self.allow_extensions:
                     self.message[-1].fields.append(new_field)
             elif in_element == "mavlink.enums.enum":
@@ -296,7 +299,7 @@ def start_element(name, attrs):
                                                         enum=attrs.get('enum', ''), increment=attrs.get('increment', ''), 
                                                         minValue=attrs.get('minValue', ''), 
                                                         maxValue=attrs.get('maxValue', ''), default=attrs.get('default', '0'), 
-                                                        reserved=attrs.get('reserved', False) ))
+                                                        reserved=attrs.get('reserved', False), multiplier=attrs.get('multiplier','') ))
 
         def is_target_system_field(m, f):
             if f.name == 'target_system':

tests/snapshottests/__snapshots__/test_wlua.ambr

@@ -530,6 +530,42 @@
           Message CRC: 0x4bdc
 
 
+    ''',
+  })
+# ---
+# name: test_wlua[common.xml-gps_raw_int.pcapng]
+  dict({
+    'returncode': 0,
+    'stderr': '',
+    'stdout': '''
+      Frame 1: 97 bytes on wire (776 bits), 97 bytes captured (776 bits) on in
+      Ethernet II, Src: 00:00:00:00:00:00, Dst: 00:00:00:00:00:00
+      Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1
+      User Datagram Protocol, Src Port: 52752, Dst Port: 14550
+      MAVLink Protocol (55)
+          Header
+              Magic value / version: MAVLink 2.0 (0xfd)
+              Payload length: 43
+              Incompatibility flag: 0x00 (0)
+              Compatibility flag: 0x00 (0)
+              Packet sequence: 58
+              System id: 1
+              Component id: MAV_COMP_ID_AUTOPILOT1 (1)
+              Message id: GPS_RAW_INT (24)
+          Payload: GPS_RAW_INT (24)
+              time_usec (uint64_t) [us]: 1583721000 (1583.721000 s)
+              fix_type (GPS_FIX_TYPE): GPS_FIX_TYPE_3D_FIX (3)
+              lat (int32_t) [degE7]: 514783466 (51.4783466 deg)
+              lon (int32_t) [degE7]: -25922214 (-2.5922214 deg)
+              alt (int32_t) [mm]: 56900
+              eph (uint16_t*1E-2): 2.33
+              epv (uint16_t*1E-2): 1.78
+              vel (uint16_t) [cm/s]: 0
+              cog (uint16_t) [cdeg]: 0
+              satellites_visible (uint8_t): 16
+          Message CRC: 0x1911
+
+
     ''',
   })
 # ---

tests/snapshottests/resources/common.xml

@@ -5042,8 +5042,8 @@
       <field type="int32_t" name="lat" units="degE7">Latitude (WGS84, EGM96 ellipsoid)</field>
       <field type="int32_t" name="lon" units="degE7">Longitude (WGS84, EGM96 ellipsoid)</field>
       <field type="int32_t" name="alt" units="mm">Altitude (MSL). Positive for up. Note that virtually all GPS modules provide the MSL altitude in addition to the WGS84 altitude.</field>
-      <field type="uint16_t" name="eph" invalid="UINT16_MAX">GPS HDOP horizontal dilution of position (unitless * 100). If unknown, set to: UINT16_MAX</field>
-      <field type="uint16_t" name="epv" invalid="UINT16_MAX">GPS VDOP vertical dilution of position (unitless * 100). If unknown, set to: UINT16_MAX</field>
+      <field type="uint16_t" name="eph" invalid="UINT16_MAX" multiplier="1E-2">GPS HDOP horizontal dilution of position (unitless * 100). If unknown, set to: UINT16_MAX</field>
+      <field type="uint16_t" name="epv" invalid="UINT16_MAX" multiplier="1E-2">GPS VDOP vertical dilution of position (unitless * 100). If unknown, set to: UINT16_MAX</field>
       <field type="uint16_t" name="vel" units="cm/s" invalid="UINT16_MAX">GPS ground speed. If unknown, set to: UINT16_MAX</field>
       <field type="uint16_t" name="cog" units="cdeg" invalid="UINT16_MAX">Course over ground (NOT heading, but direction of movement) in degrees * 100, 0.0..359.99 degrees. If unknown, set to: UINT16_MAX</field>
       <field type="uint8_t" name="satellites_visible" invalid="UINT8_MAX">Number of satellites visible. If unknown, set to UINT8_MAX</field>

tests/snapshottests/test_wlua.py

@@ -48,6 +48,8 @@ def snapshot(*args, **kwargs):
         ("common.xml", "gps_global_origin.pcapng"),
         # test command specific params in MISSION_ITEM_INT are shown
         ("common.xml", "mission_item_int.pcapng"),
+        # test multipliers on eph and epv params of GPS_RAW_INT are handled
+        ("common.xml", "gps_raw_int.pcapng"),
     ],
 )
 def test_wlua(request, tmp_path, snapshot, mdef, pcap):