Set unique hostname at boot

Set hostname to rp-xxxxxx based on the last 6 digits of the MAC address.
This is the same as used by the official Red Pitaya software.

sw/buildroot_overlay/etc/init.d/S03set_hostname.sh

@@ -0,0 +1,45 @@
+#!/bin/sh
+#
+# Set unique host name rp-xxxxxx based on MAC address.
+#
+
+start() {
+
+    # Read "ethaddr" variable from U-Boot environment in EEPROM.
+    #
+    # Environment starts at address 0x1800 and is 1024 bytes long.
+    # The environment consists of "key=value" pairs, separated by 0x00 bytes.
+    #
+    ethaddr_pair="$( dd if=/sys/bus/i2c/devices/0-0050/eeprom bs=1k skip=6 count=1 status=none | tr '\000' '\n' | grep ^ethaddr= )"
+
+    if [ -z "${ethaddr_pair}" ]; then
+        echo "ERROR: ethaddr not found in EEPROM enviroment" >&2
+        exit 1
+    fi
+
+    ethaddr="${ethaddr_pair#ethaddr=}"
+
+    suffix="$( echo $ethaddr | cut -d: -f 4- | tr -d : | tr ABCEDF abcdef )"
+    hostname="rp-${suffix}"
+
+    echo "Setting hostname ${hostname}"
+
+    echo $hostname > /etc/hostname
+    /bin/hostname -F /etc/hostname
+
+    grep -v '^127\.0\.1\.1' /etc/hosts > /etc/hosts.new
+    echo "127.0.1.1 $hostname" >>/etc/hosts.new
+    mv /etc/hosts.new /etc/hosts
+}
+
+case "$1" in
+  start)
+    start
+    ;;
+  stop|restart|reload)
+    ;;
+  *)
+    echo "Usage: $0 start"
+    exit 1
+esac
+

sw/buildroot_overlay/opt/puzzlefw/lib/functions.sh

@@ -53,7 +53,7 @@ sync_config() {
 	# Atomically replace the old file on the SD card.
 	mv ${CONFIG_MOUNTPOINT}/${fname}.new ${CONFIG_MOUNTPOINT}/${fname}
 
-	# Replace the old file in te RAM filesystem.
+	# Replace the old file in the RAM filesystem.
 	mv ${CONFIG_DIR}/${fname}.new ${CONFIG_DIR}/${fname}
     done