[graceful reboot] Add watchdog, add execution of pre_reboot_hook, fix…

… --force flag bug (sonic-net#3204)

Signed-off-by: vadymhlushko-mlnx <vadymh@nvidia.com>

scripts/reboot

@@ -1,4 +1,10 @@
 #!/bin/bash
+
+declare -r EXIT_SUCCESS=0
+declare -r EXIT_ERROR=1
+declare -r WATCHDOG_UTIL="/usr/local/bin/watchdogutil"
+declare -r PRE_REBOOT_HOOK="pre_reboot_hook"
+
 DEVPATH="/usr/share/sonic/device"
 PLAT_REBOOT="platform_reboot"
 PLATFORM_UPDATE_REBOOT_CAUSE="platform_update_reboot_cause"
@@ -34,6 +40,8 @@ PLATFORM_FWUTIL_AU_REBOOT_HANDLE="platform_fw_au_reboot_handle"
 REBOOT_SCRIPT_NAME=$(basename $0)
 REBOOT_TYPE="${REBOOT_SCRIPT_NAME}"
 TAG_LATEST=no
+REBOOT_FLAGS=""
+FORCE_REBOOT="no"
 
 function debug()
 {
@@ -123,7 +131,7 @@ function show_help_and_exit()
     echo "        -h, -? : getting this help"
     echo "        -f     : execute reboot force"
 
-    exit 0
+    exit ${EXIT_SUCCESS}
 }
 
 function setup_reboot_variables()
@@ -166,7 +174,7 @@ function check_conflict_boot_in_fw_update()
     FW_AU_TASK_FILE=$(compgen -G ${FW_AU_TASK_FILE_REGEX}) || true
     if [[ -n "${FW_AU_TASK_FILE}" ]] && [[ ! -f "${FW_AU_TASK_FILE_EXP}" ]]; then
         VERBOSE=yes debug "Firmware auto update scheduled for a different reboot: ${FW_AU_TASK_FILE}"
-        exit 1
+        exit ${EXIT_ERROR}
     fi
 }
 
@@ -183,6 +191,10 @@ function parse_options()
             t )
                 TAG_LATEST=no
                 ;;
+            f )
+                REBOOT_FLAGS+=" -f"
+                FORCE_REBOOT="yes"
+                ;;
         esac
     done
 }
@@ -192,7 +204,7 @@ parse_options $@
 # Exit if not superuser
 if [[ "$EUID" -ne 0 ]]; then
     echo "This command must be run as root" >&2
-    exit 1
+    exit ${EXIT_ERROR}
 fi
 
 debug "User requested rebooting device ..."
@@ -242,6 +254,23 @@ if [ -x ${DEVPATH}/${PLATFORM}/${PLATFORM_UPDATE_REBOOT_CAUSE} ]; then
     ${DEVPATH}/${PLATFORM}/${PLATFORM_UPDATE_REBOOT_CAUSE}
 fi
 
+if [ -x ${DEVPATH}/${PLATFORM}/${PRE_REBOOT_HOOK} ]; then
+    debug "Executing the pre-reboot script"
+    ${DEVPATH}/${PLATFORM}/${PRE_REBOOT_HOOK}
+    EXIT_CODE=$?
+    if [[ ${EXIT_CODE} != ${EXIT_SUCCESS} ]]; then
+        if [[ "${FORCE_REBOOT}" != "yes" ]]; then
+            echo "Reboot is interrupted: use -f (force) to override"
+            exit ${EXIT_ERROR}
+        fi
+    fi
+fi
+
+if [ -x ${WATCHDOG_UTIL} ]; then
+    debug "Enabling the Watchdog before reboot"
+    ${WATCHDOG_UTIL} arm
+fi
+
 if [ -x ${DEVPATH}/${PLATFORM}/${PLAT_REBOOT} ]; then
     VERBOSE=yes debug "Rebooting with platform ${PLATFORM} specific tool ..."
     ${DEVPATH}/${PLATFORM}/${PLAT_REBOOT} $@
@@ -260,4 +289,4 @@ if [ -x ${DEVPATH}/${PLATFORM}/${PLAT_REBOOT} ]; then
 fi
 
 VERBOSE=yes debug "Issuing OS-level reboot ..." >&2
-exec /sbin/reboot $@
+exec /sbin/reboot ${REBOOT_FLAGS}