[shortkey] allow to use Qt style for common key modifiers

this allow to avoid GTK style which makes the xml not valid because
of < and > characters (this makes some parsers fail)

conf/flight_plans/basic.xml

@@ -41,7 +41,7 @@
       <set value="0" var="autopilot_flight_time"/>
       <go from="HOME" throttle="1.0" vmode="throttle" wp="CLIMB" pitch="15"/>
     </block>
-    <block key="<Control>a" name="Standby" strip_button="Standby" strip_icon="home.png" group="home">
+    <block key="Ctrl+a" name="Standby" strip_button="Standby" strip_icon="home.png" group="home">
       <circle radius="nav_radius" wp="STDBY"/>
     </block>
     <block key="F8" name="Figure 8 around wp 1" strip_button="Figure 8 (wp 1-2)" strip_icon="eight.png" group="base_pattern">

conf/flight_plans/mission_fw.xml

@@ -31,7 +31,7 @@
       <set value="0" var="autopilot_flight_time"/>
       <go from="HOME" throttle="1.0" vmode="throttle" wp="CLIMB" pitch="15"/>
     </block>
-    <block key="<Control>a" name="Standby" strip_button="Standby" strip_icon="home.png" group="home">
+    <block key="Ctrl+a" name="Standby" strip_button="Standby" strip_icon="home.png" group="home">
       <circle radius="nav_radius" wp="STDBY"/>
     </block>
     <block name="Mission" strip_button="Mission">

conf/flight_plans/poles.xml

@@ -37,7 +37,7 @@
       <set value="0" var="autopilot_flight_time"/>
       <go from="HOME" pitch="15" throttle="1.0" vmode="throttle" wp="CLIMB"/>
     </block>
-    <block key="<Control>a" name="Standby" strip_button="Standby" strip_icon="home.png">
+    <block key="Ctrl+a" name="Standby" strip_button="Standby" strip_icon="home.png">
       <circle radius="nav_radius" wp="STDBY"/>
     </block>
     <block name="Poles 1" strip_button="Line (wp 1-2)" strip_icon="line.png">

conf/flight_plans/zamboni_survey_test.xml

@@ -75,7 +75,7 @@
       <go approaching_time="0" from="AF" hmode="route" throttle="0.0" vmode="throttle" wp="TD"/>
       <attitude roll="0.0" throttle="0.0" until="FALSE" vmode="throttle"/>
     </block>
-    <block group="home" key="<Control>a" name="Standby" strip_button="Standby" strip_icon="home.png">
+    <block group="home" key="Ctrl+a" name="Standby" strip_button="Standby" strip_icon="home.png">
       <circle radius="nav_radius" wp="STDBY"/>
     </block>
   </blocks>

sw/ground_segment/cockpit/live.ml

@@ -525,7 +525,7 @@ let create_ac = fun alert (geomap:G.widget) (acs_notebook:GPack.notebook) (ac_id
     let id = ExtXml.int_attrib block "no" in
     begin (* Is it a key short cut ? *)
       try
-        let key, modifiers = GtkData.AccelGroup.parse (Xml.attrib block "key") in
+        let key, modifiers = GtkData.AccelGroup.parse (Pprz.key_modifiers_of_string (Xml.attrib block "key")) in
         keys := (key, (modifiers, id)) :: !keys
       with
           _ -> ()

sw/ground_segment/cockpit/page_settings.ml

@@ -58,7 +58,7 @@ let search_index = fun value array ->
 
 
 let add_key = fun xml do_change keys ->
-  let key, modifiers = GtkData.AccelGroup.parse (Xml.attrib xml "key")
+  let key, modifiers = GtkData.AccelGroup.parse (Pprz.key_modifiers_of_string (Xml.attrib xml "key"))
   and value = ExtXml.float_attrib xml "value" in
   keys := (key, (modifiers, fun () -> do_change value)) :: !keys
 

sw/lib/ocaml/pprz.ml

@@ -241,6 +241,17 @@ let alt_unit_coef_of_xml = fun ?auto xml ->
     in
     coef
 
+let key_modifiers_of_string = fun key ->
+  let key_split = Str.split (Str.regexp "[A-Za-z]+\\+") key in
+  let keys = List.map (fun k ->
+    match k with
+    | "Ctrl" -> "<Control>"
+    | "Alt" -> "<Alt>"
+    | "Shift" -> "<Shift>"
+    | "Meta" -> "<Meta>"
+    | x -> x
+  ) key_split in
+  String.concat "" keys
 
 let pipe_regexp = Str.regexp "|"
 let field_of_xml = fun xml ->

sw/lib/ocaml/pprz.mli

@@ -109,6 +109,12 @@ val alt_unit_coef_of_xml : ?auto:string -> Xml.xml -> string
 (** Return coef for alternate unit
  *)
 
+val key_modifiers_of_string : string -> string
+(** Convert key modifiers from Qt style (without '<' or '>', separated with '+')
+ *  to GTK style.
+ *  Supported modifiers are Alt, Ctrl, Shift and Meta
+ *)
+
 exception Unknown_msg_name of string * string
 (** [Unknown_msg_name (name, class_name)] Raised if message [name] is not
 found in class [class_name]. *)