consistent usage/help with other releng scripts

releng/run_all_auto

@@ -13,10 +13,13 @@ PASSED_OPTIONS="$@"
 RELENG_XORRISO=
 CLEANUP_LOG=0
 
-not_in_releng_exit() {
+# It is not a good idea to include inc/releng_getopts.inc with the
+# master script as it calls the subordinate scripts and they include
+# this file too, and we want to avoid sharing variable with subshells
+if [ ! -f inc/releng_getopts.inc ]; then
   printf "\nPlease execute the tests from releng directory.\n\n"
   exit 1
-}
+fi
 
 # To catch the exit value of a command in a pipe
 return_value_file="$GEN_DATA_DIR"/run_all_"$$"_return_value
@@ -52,17 +55,45 @@ count_lines()
  return 0
 }
 
-# It is not a good idea to include inc/releng_getopts.inc with the
-# master script as it calls the subordinate scripts and they include
-# this file too, and we want to avoid sharing variable with subshells
-if [ ! -f inc/releng_getopts.inc ]; then
-  not_in_releng_exit
-fi
+#############################################
+print_usage()
+{
+cat << HLP
+
+${SELF} runs executables from releng directory starting with auto_*,
+and passing them its own options. stdout/stderr output is stored in:
+./${CLOG}
+
+Usage: ${SELF} -x path/to/xorriso [-k] [-c] [-h]
+   -x  absolute or relative path to xorriso binary to be run.
+   -k  keep self-generated data in ./${GEN_DATA_DIR}.
+   -c  cleanup self-generated data kept from previous run and exit.
+   -h  print this help text
+				   
+Examples:
+# run xorriso and keep the self-generated data
+ $ ./${SELF} -x path/to/xorriso -k
+
+# clean up self-generated data from previous run
+ $ ./${SELF} -c
+
+HLP
+}
 
 #############################################
+if [ ! "${1}" ]; then
+ print_usage
+ exit 0
+fi
 next_is=
 for i in "$@"
 do
+  if test x"$i" = x"-h" -o x"$i" = x"--h" -o x"$i" = x"-help" -o x"$i" = x"--help"
+  then :
+       print_usage
+       exit 0
+  fi
+
   if test "$next_is" = "ignore"
   then :
   elif test "$next_is" = "x"
@@ -85,24 +116,6 @@ then
        exit 31
 fi
 
-if [ ! "${1}" ]; then
-cat << HLP
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-${SELF} runs executables from CWD starting 
-with auto_*, passing them its own options.
-stdout/stderr output stored in:
- ${CLOG}
-
-examples:
-# run xorriso and keep the self-generated data
- $ ./${SELF} -x path/to/xorriso [-k]
-
-# clean up self-generated data from previous run
- $ ./${SELF} -c
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-HLP
- exit 31
-fi
 
 ########################################################
  if [ -f "${CLOG}" ]; then