Check submodules during each build

Makefile

@@ -109,6 +109,7 @@ endif
 # describe how to build a cmake config
 define cmake-build
 +@if [ $(PX4_CMAKE_GENERATOR) = "Ninja" ] && [ -e $(PWD)/build_$@/Makefile ]; then rm -rf $(PWD)/build_$@; fi
++Tools/check_submodules.sh 
 +@if [ ! -e $(PWD)/build_$@/CMakeCache.txt ]; then mkdir -p $(PWD)/build_$@ && cd $(PWD)/build_$@ && cmake .. -G$(PX4_CMAKE_GENERATOR) -DCONFIG=$(1); fi
 +$(PX4_MAKE) -C $(PWD)/build_$@ $(PX4_MAKE_ARGS) $(ARGS)
 endef

Tools/check_submodules.sh

@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+
+[ -n "$GIT_SUBMODULES_ARE_EVIL" ] && {
+    # GIT_SUBMODULES_ARE_EVIL is set, meaning user doesn't want submodules
+    echo "Skipping submodules. NUTTX_SRC is set to $NUTTX_SRC"
+    exit 0
+}
+
+GITSTATUS=$(git status)
+
+function check_git_submodule {
+
+if [ -d $1 ];
+	then
+	SUBMODULE_STATUS=$(git submodule summary "$1")
+	STATUSRETVAL=$(echo $SUBMODULE_STATUS | grep -A20 -i "$1" | grep "<")
+	if [ -z "$STATUSRETVAL" ]; then
+		echo "Checked $1 submodule, correct version found"
+	else
+		echo -e "\033[31mChecked $1 submodule, ACTION REQUIRED:"
+		echo ""
+		echo ""
+		echo -e "New commits required:"
+		echo -e "$SUBMODULE_STATUS\033[0m"
+		echo ""
+		echo ""
+		echo "   $1 submodule not at correct version. Did you intentionally change the submodule?"
+		echo "   If yes, hit 'y' and <ENTER> to continue the build. If not, hit <ENTER> to abort."
+		echo -e "   Hit 'u' and <ENTER> to update ALL submodules and resolve this (performs \033[94mgit submodule update --init --recursive\033[0m)."
+		echo -e "   Use \033[94mgit add $1 && git commit -m 'Updated $1'\033[0m to choose this submodule version (careful!)"
+		echo ""
+		read user_cmd
+		if [ "$user_cmd" == "y" ]
+		then
+			echo "Continuing build with manually overridden submodule.."
+		else
+			if [ "$user_cmd" == "u" ]
+			then
+				git submodule update --init --recursive
+				echo "Submodule fixed, continuing build.."
+			else
+				echo "Build aborted."
+				exit 1
+			fi
+		fi
+	fi
+else
+	git submodule update --init --recursive;
+	git submodule update;
+fi
+
+}
+
+check_git_submodule NuttX
+check_git_submodule Tools/gencpp
+check_git_submodule Tools/genmsg
+check_git_submodule Tools/jMAVSim
+check_git_submodule Tools/sitl_gazebo
+check_git_submodule cmake/cmake_hexagon
+check_git_submodule mavlink/include/mavlink/v1.0
+check_git_submodule src/lib/DriverFramework
+check_git_submodule src/lib/dspal
+check_git_submodule src/lib/ecl
+check_git_submodule src/lib/matrix
+check_git_submodule src/modules/uavcan/libuavcan
+check_git_submodule unittests/googletest
+
+exit 0