Enhance blink.sh

os-buildroot/override/root/blink.sh

@@ -1,10 +1,51 @@
 #!/bin/sh
-
 set -u
 
-if [ $# -ne 3 ]; then
-    echo "Usage: blink.sh RANGE_FROM RANGE_TO SLEEP"
-    exit 1
+VERBOSE=0
+PIN=""
+SLEEP=1
+GPIOS=""
+
+while getopts "hvr:p:s:" OPT; do
+    case "$OPT" in
+    h)
+        echo "Usage:   blink.sh [-hv] [-r PIN_RANGE_FROM-PIN_RANGE_TO] [-p PIN] [-s SLEEP_SEC]"
+        echo "Example: blink.sh -r 0-10 -p 12"
+        echo "         (blink from GPIO 0 to 10 and 12)"
+        exit 0
+        ;;
+    v)
+        VERBOSE=1
+        ;;
+    r)
+        RE='^([0-9]+)-([0-9]+)$'
+        if echo $OPTARG | grep -qvE $RE; then
+            echo "Error: invalid range: $OPTARG"
+            exit 1
+        fi
+        FROM=$(echo $OPTARG | sed -E "s/$RE/\\1/")
+        TO=$(echo $OPTARG | sed -E "s/$RE/\\2/")
+        GPIOS="$GPIOS$(seq -s " " $FROM $TO) "
+        ;;
+    p)
+        if echo $OPTARG | grep -qvE "^[0-9]+$"; then
+            echo "Error: invalid pin number: $OPTARG"
+            exit 1
+        fi
+        GPIOS="$GPIOS$OPTARG "
+        ;;
+    s)
+        if echo $OPTARG | grep -qvE "^[0-9]+$"; then
+            echo "Error: invalid sleep duration: $OPTARG"
+            exit 1
+        fi
+        SLEEP=$OPTARG
+        ;;
+    esac
+done
+
+if [ $VERBOSE -eq 1 ]; then
+    echo "Pins to iterate over: $GPIOS"
 fi
 
 if [ "$(id -u)" -ne "0" ]; then
@@ -12,10 +53,6 @@ if [ "$(id -u)" -ne "0" ]; then
     exit 1
 fi
 
-FROM=$1
-TO=$2
-SLEEP=$3
-GPIOS=$(seq $FROM $TO)
 AVAILABLE_GPIOS=""
 
 export_gpio() {
@@ -72,3 +109,4 @@ while [ 1 ]; do
 
     sleep $SLEEP
 done
+