Autobuild: Combine and simplify Linux build scripts

.github/autobuild/linux_deb.sh

@@ -0,0 +1,49 @@
+#!/bin/bash
+set -eu
+
+if [[ ! ${jamulus_buildversionstring:-} =~ [0-9]+\.[0-9]+\.[0-9]+ ]]; then
+    echo "Environment variable jamulus_buildversionstring has to be set to a valid version string"
+    exit 1
+fi
+
+setup() {
+    echo "Update system..."
+    sudo apt-get -qq update
+
+    echo "Install dependencies..."
+    sudo apt-get -qq --no-install-recommends -y install devscripts build-essential debhelper libjack-jackd2-dev qtbase5-dev qttools5-dev-tools
+}
+
+build_app_as_deb() {
+    ./linux/deploy_deb.sh
+}
+
+pass_artifacts_to_job() {
+    mkdir deploy
+
+    # rename headless first, so wildcard pattern matches only one file each
+    artifact_deploy_filename_1="jamulus_headless_${jamulus_buildversionstring}_ubuntu_amd64.deb"
+    echo "Moving headless build artifact to deploy/${artifact_deploy_filename_1}"
+    mv ../jamulus-headless*_amd64.deb "./deploy/${artifact_deploy_filename_1}"
+    echo "::set-output name=artifact_1::${artifact_deploy_filename_1}"
+
+    artifact_deploy_filename_2="jamulus_${jamulus_buildversionstring}_ubuntu_amd64.deb"
+    echo "Moving regular build artifact to deploy/${artifact_deploy_filename_2}"
+    mv ../jamulus*_amd64.deb "./deploy/${artifact_deploy_filename_2}"
+    echo "::set-output name=artifact_2::${artifact_deploy_filename_2}"
+}
+
+case "${1:-}" in
+    setup)
+        setup
+        ;;
+    build)
+        build_app_as_deb
+        ;;
+    get-artifacts)
+        pass_artifacts_to_job
+        ;;
+    *)
+        echo "Unknown stage '${1:-}'"
+        exit 1
+esac

.github/workflows/autobuild.yml

@@ -97,9 +97,9 @@ jobs:
           - config_name:            Linux .deb (artifacts+codeQL)
             target_os:              linux
             building_on_os:         ubuntu-18.04
-            cmd1_prebuild:          "./autobuild/linux/autobuild_deb_1_prepare.sh"
-            cmd2_build:             "./autobuild/linux/autobuild_deb_2_build.sh"
-            cmd3_postbuild:         "./autobuild/linux/autobuild_deb_3_copy_files.sh"
+            cmd1_prebuild:          ./.github/autobuild/linux_deb.sh setup
+            cmd2_build:             ./.github/autobuild/linux_deb.sh build
+            cmd3_postbuild:         ./.github/autobuild/linux_deb.sh get-artifacts
             run_codeql:             true
 
           - config_name:            MacOS (artifacts+codeQL)