[mission] fix segmentation fault and add generic mission FP

conf/flight_plans/mission_fw.xml

@@ -0,0 +1,63 @@
+<!DOCTYPE flight_plan SYSTEM "flight_plan.dtd">
+
+<flight_plan alt="260" ground_alt="185" lat0="43.46223" lon0="1.27289" max_dist_from_home="1500" name="Basic" security_height="25">
+  <header/>
+  <waypoints>
+    <waypoint name="HOME" x="0" y="0"/>
+    <waypoint name="STDBY" x="49.5" y="100.1"/>
+    <waypoint alt="215.0" name="AF" x="177.4" y="45.1"/>
+    <waypoint alt="185.0" name="TD" x="28.8" y="57.0"/>
+    <waypoint name="_BASELEG" x="168.8" y="-13.8"/>
+    <waypoint name="CLIMB" x="-114.5" y="162.3"/>
+  </waypoints>
+  <exceptions/>
+  <blocks>
+    <block name="Wait GPS">
+      <set value="1" var="kill_throttle"/>
+      <while cond="!GpsFixValid()"/>
+    </block>
+    <block name="Geo init">
+      <while cond="LessThan(NavBlockTime(), 10)"/>
+      <call fun="NavSetGroundReferenceHere()"/>
+    </block>
+    <block name="Holding point">
+      <!--set var="nav_mode" value="NAV_MODE_ROLL"/-->
+      <set value="1" var="kill_throttle"/>
+      <attitude roll="0" throttle="0" vmode="throttle"/>
+    </block>
+    <block key="t" name="Takeoff" strip_button="Takeoff (wp CLIMB)" strip_icon="takeoff.png" group="home">
+      <exception cond="GetPosAlt() > ground_alt+25" deroute="Standby"/>
+      <set value="0" var="kill_throttle"/>
+      <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">
+      <circle radius="nav_radius" wp="STDBY"/>
+    </block>
+    <block name="Mission" strip_button="Mission">
+      <call fun="mission_run()"/>
+      <deroute block="Standby"/>
+    </block>
+    <block name="Land Right AF-TD" strip_button="Land right (wp AF-TD)" strip_icon="land-right.png" group="land">
+      <set value="DEFAULT_CIRCLE_RADIUS" var="nav_radius"/>
+      <deroute block="land"/>
+    </block>
+    <block name="Land Left AF-TD" strip_button="Land left (wp AF-TD)" strip_icon="land-left.png" group="land">
+      <set value="-DEFAULT_CIRCLE_RADIUS" var="nav_radius"/>
+      <deroute block="land"/>
+    </block>
+    <block name="land">
+      <call fun="nav_compute_baseleg(WP_AF, WP_TD, WP__BASELEG, nav_radius)"/>
+      <circle radius="nav_radius" until="NavCircleCount() > 0.5" wp="_BASELEG"/>
+      <circle radius="nav_radius" until="And(NavQdrCloseTo(DegOfRad(baseleg_out_qdr)-(nav_radius/fabs(nav_radius))*10), 10 > fabs(GetPosAlt() - WaypointAlt(WP__BASELEG)))" wp="_BASELEG"/>
+    </block>
+    <block name="final">
+      <exception cond="ground_alt + 10 > GetPosAlt()" deroute="flare"/>
+      <go from="AF" hmode="route" vmode="glide" wp="TD"/>
+    </block>
+    <block name="flare">
+      <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>
+  </blocks>
+</flight_plan>

sw/airborne/modules/mission/mission.c

@@ -76,13 +76,11 @@ bool_t mission_insert(enum MissionInsertMode insert, struct _mission_element * e
 
 }
 
-bool_t mission_get(struct _mission_element * element __attribute__((unused))) {
+struct _mission_element * mission_get(void) {
   if (mission.current_idx == mission.insert_idx) {
-    element = NULL;
+    return NULL;
-    return FALSE;
   }
-  element = &(mission.elements[mission.current_idx]);
+  return &(mission.elements[mission.current_idx]);
-  return TRUE;
 }
 
 

sw/airborne/modules/mission/mission.h

@@ -104,10 +104,9 @@ extern void mission_init(void);
 extern bool_t mission_insert(enum MissionInsertMode insert, struct _mission_element * element);
 
 /** Get current mission element
- * @param element pointer to the current mission element
+ * @return return a pointer to the next mission element or NULL if no more elements
- * @return TRUE if valid element, FALSE if mission queue is empty (add element is set to NULL)
  */
-extern bool_t mission_get(struct _mission_element * element);
+extern struct _mission_element * mission_get(void);
 
 /** Run mission
  *

sw/airborne/modules/mission/mission_fw_nav.c

@@ -105,7 +105,7 @@ static inline bool_t mission_nav_path(struct _mission_path * path) {
 int mission_run() {
   // current element
   struct _mission_element * el = NULL;
-  if (!mission_get(el)) {
+  if ((el = mission_get()) == NULL) {
     // TODO do something special like a waiting circle before ending the mission ?
     return FALSE; // end of mission
   }