Fix launch.script to not exit prematurely

Use "return" instead of "exit" where possible, especially in
function definitions.

Also fixed the exit codes to match the LSB spec for some specific
conditions (fixes gh-3521).

Fixes gh-3199, fixes gh-3535

spring-boot-tools/spring-boot-loader-tools/src/main/resources/org/springframework/boot/loader/tools/launch.script

@@ -71,8 +71,8 @@ echoYellow() { echo $'\e[0;33m'$1$'\e[0m'; }
 
 # Utility functions
 checkPermissions() {
-  touch "$pid_file" &> /dev/null || { echoRed "Operation not permitted (cannot access pid file)"; exit 1; }
-  touch "$log_file" &> /dev/null || { echoRed "Operation not permitted (cannot access log file)"; exit 1; }
+  touch "$pid_file" &> /dev/null || { echoRed "Operation not permitted (cannot access pid file)"; return 4; }
+  touch "$log_file" &> /dev/null || { echoRed "Operation not permitted (cannot access log file)"; return 4; }
 }
 
 isRunning() {
@@ -115,40 +115,40 @@ command="$javaexe -jar -Dsun.misc.URLClassPath.disableJarChecking=true $JAVA_OPT
 start() {
   if [[ -f "$pid_file" ]]; then
     pid=$(cat "$pid_file")
-    isRunning $pid && { echoYellow "Already running [$pid]"; exit 0; }
+    isRunning $pid && { echoYellow "Already running [$pid]"; return 0; }
   fi
   pushd $(dirname "$jarfile") > /dev/null
   if [[ -n "$run_user" ]]; then
     mkdir "$PID_FOLDER" &> /dev/null
-    checkPermissions
+    checkPermissions || return $?
     chown "$run_user" "$PID_FOLDER"
     chown "$run_user" "$pid_file"
     chown "$run_user" "$log_file"
     su -c "$command &> \"$log_file\" & echo \$!" $run_user > "$pid_file"
     pid=$(cat "$pid_file")
   else
-    checkPermissions
+    checkPermissions || return $?
     $command &> "$log_file" &
     pid=$!
     disown $pid
     echo "$pid" > "$pid_file"
   fi
-  [[ -z $pid ]] && { echoRed "Failed to start"; exit 1; }
+  [[ -z $pid ]] && { echoRed "Failed to start"; return 1; }
   echoGreen "Started [$pid]"
 }
 
 stop() {
-  [[ -f $pid_file ]] || { echoRed "Not running (pidfile not found)"; exit 1; }
+  [[ -f $pid_file ]] || { echoRed "Not running (pidfile not found)"; return 1; }
   pid=$(cat "$pid_file")
   rm -f "$pid_file"
-  isRunning $pid || { echoRed "Not running (process ${pid} not found)"; exit 1; }
-  kill -HUP $pid &> /dev/null || { echoRed "Unable to kill process ${pid}"; exit 1; }
-  for i in $(seq 1 20); do
-    isRunning ${pid} || { echoGreen "Stopped [$pid]"; rm -f $pid_file; exit 0; }
+  isRunning $pid || { echoRed "Not running (process ${pid} not found)"; return 1; }
+  kill -HUP $pid &> /dev/null || { echoRed "Unable to kill process ${pid}"; return 3; }
+  for i in $(seq 1 60); do
+    isRunning ${pid} || { echoGreen "Stopped [$pid]"; rm -f $pid_file; return 0; }
     sleep 1
   done
   echoRed "Unable to kill process ${pid}";
-  exit 3;
+  return 3;
 }
 
 restart() {
@@ -157,31 +157,33 @@ restart() {
 }
 
 status() {
-  [[ -f $pid_file ]] || { echoRed "Not running"; exit 1; }
+  [[ -f $pid_file ]] || { echoRed "Not running"; return 1; }
   pid=$(cat "$pid_file")
-  isRunning $pid || { echoRed "Not running (process ${pid} not found)"; exit 1; }
+  isRunning $pid || { echoRed "Not running (process ${pid} not found)"; return 3; }
   echoGreen "Running [$pid]"
-  exit 0
+  return 0
 }
 
 run() {
   pushd $(dirname "$jarfile") > /dev/null
   exec $command
+  result = $?
   popd
+  return $result
 }
 
 # Call the appropriate action function
 case "$action" in
 start)
-  start "$@";;
+  start "$@"; exit $?;;
 stop)
-  stop "$@";;
+  stop "$@"; exit $?;;
 restart)
-  restart "$@";;
+  restart "$@"; exit $?;;
 status)
-  status "$@";;
+  status "$@"; exit $?;;
 run)
-  run "$@";;
+  run "$@"; exit $?;;
 *)
   echo "Usage: $0 {start|stop|restart|status|run}"; exit 1;
 esac