From 5ae52038fa8132aff51b4d5abb8f775f2c1b2951 Mon Sep 17 00:00:00 2001
From: Peter Barker <pbarker@barker.dropbear.id.au>
Date: Wed, 30 May 2018 10:47:08 +1000
Subject: [PATCH] Copter: make setting of home boolean in preparation for
 sanity checks

---
 ArduCopter/Copter.h        | 4 ++--
 ArduCopter/GCS_Mavlink.cpp | 8 ++++++--
 ArduCopter/GCS_Mavlink.h   | 4 ++--
 ArduCopter/commands.cpp    | 8 ++++++--
 ArduCopter/mode_auto.cpp   | 8 ++++++--
 ArduCopter/motors.cpp      | 4 +++-
 6 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/ArduCopter/Copter.h b/ArduCopter/Copter.h
index a8c11f88ec..074285fedf 100644
--- a/ArduCopter/Copter.h
+++ b/ArduCopter/Copter.h
@@ -673,8 +673,8 @@ private:
     // commands.cpp
     void update_home_from_EKF();
     void set_home_to_current_location_inflight();
-    bool set_home_to_current_location(bool lock);
-    bool set_home(const Location& loc, bool lock);
+    bool set_home_to_current_location(bool lock) WARN_IF_UNUSED;
+    bool set_home(const Location& loc, bool lock) WARN_IF_UNUSED;
     bool far_from_EKF_origin(const Location& loc);
 
     // compassmot.cpp
diff --git a/ArduCopter/GCS_Mavlink.cpp b/ArduCopter/GCS_Mavlink.cpp
index 7ee9bc34aa..105208c1c7 100644
--- a/ArduCopter/GCS_Mavlink.cpp
+++ b/ArduCopter/GCS_Mavlink.cpp
@@ -1249,7 +1249,9 @@ void GCS_MAVLINK_Copter::handleMessage(mavlink_message_t* msg)
         mavlink_set_home_position_t packet;
         mavlink_msg_set_home_position_decode(msg, &packet);
         if((packet.latitude == 0) && (packet.longitude == 0) && (packet.altitude == 0)) {
-            copter.set_home_to_current_location(true);
+            if (!copter.set_home_to_current_location(true)) {
+                // silently ignored
+            }
         } else {
             // sanity check location
             if (!check_latlng(packet.latitude, packet.longitude)) {
@@ -1259,7 +1261,9 @@ void GCS_MAVLINK_Copter::handleMessage(mavlink_message_t* msg)
             new_home_loc.lat = packet.latitude;
             new_home_loc.lng = packet.longitude;
             new_home_loc.alt = packet.altitude / 10;
-            copter.set_home(new_home_loc, true);
+            if (!copter.set_home(new_home_loc, true)) {
+                // silently ignored
+            }
         }
         break;
     }
diff --git a/ArduCopter/GCS_Mavlink.h b/ArduCopter/GCS_Mavlink.h
index 53961c8d5d..bf777b16b9 100644
--- a/ArduCopter/GCS_Mavlink.h
+++ b/ArduCopter/GCS_Mavlink.h
@@ -38,8 +38,8 @@ protected:
 
     void handle_mount_message(const mavlink_message_t* msg) override;
 
-    bool set_home_to_current_location(bool lock) override;
-    bool set_home(const Location& loc, bool lock) override;
+    bool set_home_to_current_location(bool lock) override WARN_IF_UNUSED;
+    bool set_home(const Location& loc, bool lock) override WARN_IF_UNUSED;
 
 private:
 
diff --git a/ArduCopter/commands.cpp b/ArduCopter/commands.cpp
index c1d88b2d70..7ca6fabd84 100644
--- a/ArduCopter/commands.cpp
+++ b/ArduCopter/commands.cpp
@@ -13,7 +13,9 @@ void Copter::update_home_from_EKF()
         set_home_to_current_location_inflight();
     } else {
         // move home to current ekf location (this will set home_state to HOME_SET)
-        set_home_to_current_location(false);
+        if (!set_home_to_current_location(false)) {
+            // ignore failure
+        }
     }
 }
 
@@ -75,7 +77,9 @@ bool Copter::set_home(const Location& loc, bool lock)
     const bool home_was_set = ahrs.home_is_set();
 
     // set ahrs home (used for RTL)
-    ahrs.set_home(loc);
+    if (!ahrs.set_home(loc)) {
+        return false;
+    }
 
     // init inav and compass declination
     if (!home_was_set) {
diff --git a/ArduCopter/mode_auto.cpp b/ArduCopter/mode_auto.cpp
index 5ef019fbf2..a03ecefcdd 100644
--- a/ArduCopter/mode_auto.cpp
+++ b/ArduCopter/mode_auto.cpp
@@ -1360,9 +1360,13 @@ void Copter::ModeAuto::do_change_speed(const AP_Mission::Mission_Command& cmd)
 void Copter::ModeAuto::do_set_home(const AP_Mission::Mission_Command& cmd)
 {
     if (cmd.p1 == 1 || (cmd.content.location.lat == 0 && cmd.content.location.lng == 0 && cmd.content.location.alt == 0)) {
-        copter.set_home_to_current_location(false);
+        if (!copter.set_home_to_current_location(false)) {
+            // ignore failure
+        }
     } else {
-        copter.set_home(cmd.content.location, false);
+        if (!copter.set_home(cmd.content.location, false)) {
+            // ignore failure
+        }
     }
 }
 
diff --git a/ArduCopter/motors.cpp b/ArduCopter/motors.cpp
index f461839c9f..fdc9fd7193 100644
--- a/ArduCopter/motors.cpp
+++ b/ArduCopter/motors.cpp
@@ -188,7 +188,9 @@ bool Copter::init_arm_motors(const AP_Arming::ArmingMethod method, const bool do
         arming_altitude_m = 0;        
     } else if (!ahrs.home_is_locked()) {
         // Reset home position if it has already been set before (but not locked)
-        set_home_to_current_location(false);
+        if (!set_home_to_current_location(false)) {
+            // ignore failure
+        }
 
         // remember the height when we armed
         arming_altitude_m = inertial_nav.get_altitude() * 0.01;