#!/bin/bash

#Copyright 2020-present Open Networking Foundation
#
#Licensed under the Apache License, Version 2.0 (the "License");
#you may not use this file except in compliance with the License.
#You may obtain a copy of the License at
#
#http://www.apache.org/licenses/LICENSE-2.0
#
#Unless required by applicable law or agreed to in writing, software
#distributed under the License is distributed on an "AS IS" BASIS,
#WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#See the License for the specific language governing permissions and
#limitations under the License.

# This script is a watchdog to monitor openolt and dev_mgmt_daemon processes
# It restarts the processes when they crash
# When OLT is working in in-band mode, it just monitors the dev_mgmt_daemon
# process to start with. Once the openolt processes is also up, it starts
# monitoring both the processes.
# When OLT is working in out-of-band, it monitors both the processes to start
# with. When either of the processes crash, it restarts both the processes.

PID_MONITOR_INTERVAL=1 # in seconds
MAX_WAIT_TIMER_FOR_OPENOLT_PROCESS_TO_START=120

WATCHDOG_LOG_FILE="/var/log/openolt_process_watchdog.log"

BRCM_DIR="/broadcom"

# inband config file
INBAND_CONFIG_FILE="${BRCM_DIR}/inband.config"

OLT_MODEL=$(cat /sys/devices/virtual/dmi/id/board_name)

ASF16_MODEL="ASXvOLT16"

# vlan id for asfvolt16
ASFVOLT16_VLAN_ID_ETH2=

# vlan id for asgvolt64
ASGVOLT64_VLAN_ID_ETH1=


#------------------------------------------------------------------------------
# Function Name: LOG
# Description:
#    Logs to WATCHDOG_LOG_FILE
#
# Globals:
#    None
#
# Arguments:
#    string to be logged
#
# Returns:
#    None
#------------------------------------------------------------------------------
LOG() {
    echo `date`" $1" >> ${WATCHDOG_LOG_FILE}
}

#------------------------------------------------------------------------------
# Function Name: get_vlan_ids
# Description:
#    This function facilitates to fetch vlan id from inband configuration file
#    located at /broadcom/inband.config
#
# Globals:
#    INBAND_CONFIG_FILE, ASFVOLT16_VLAN_ID_ETH2, ASFVOLT16_VLAN_ID_ETH3,
#    ASGVOLT64_VLAN_ID_ETH1, ASGVOLT64_VLAN_ID_ETH2
#
# Arguments:
#    None
#
# Returns:
#    None
#------------------------------------------------------------------------------
get_vlan_ids() {
    # Read inband.config file to fetch vlan id information
    if [ -f ${INBAND_CONFIG_FILE} ]; then
        if [ "${OLT_MODEL}" = ${ASF16_MODEL} ]; then
            ASFVOLT16_VLAN_ID_ETH2=$(awk '/asfvolt16_vlan_id_eth2/{print $0}' ${INBAND_CONFIG_FILE} | awk -F "=" '{print $2}')
        else
            ASGVOLT64_VLAN_ID_ETH1=$(awk '/asgvolt64_vlan_id_eth1/{print $0}' ${INBAND_CONFIG_FILE} | awk -F "=" '{print $2}')
        fi

        if [ -z ${ASFVOLT16_VLAN_ID_ETH2} ] && [ -z ${ASGVOLT64_VLAN_ID_ETH1} ]; then
            LOG "ERROR: vlan ids not valid"
            exit 1
        fi
    else
        LOG "ERROR: ${INBAND_CONFIG_FILE} not found, using default value 4093"
    fi
}

#------------------------------------------------------------------------------
# Function Name: monitor_openolt_and_dev_mgmt_daemon_process
# Description:
#    Monitors openolt and dev_mgmt_daemon processes in an infinite loop.
#    Restarts both the processes if either of them exits
#
# Globals:
#    None
#
# Arguments:
#    None
#
# Returns:
#
#------------------------------------------------------------------------------
monitor_openolt_and_dev_mgmt_daemon_process() {
    LOG "start monitor openolt and dev_mgmt_daemon processes"

    get_vlan_ids
    if [ "${OLT_MODEL}" = ${ASF16_MODEL} ]; then
        INBAND_IF="eth2.${ASFVOLT16_VLAN_ID_ETH2}"
    else
        INBAND_IF="eth1.${ASGVOLT64_VLAN_ID_ETH1}"
    fi

    # This is builtin bash variable that tracks the number of seconds
    # elapsed since the shell started. We can reset to 0 and the timer
    # starts from here
    SECONDS=0
    while true; do

        DEV_MGMT_DAEMON_PID=`pidof /broadcom/dev_mgmt_daemon`
        OPENOLT_PID=$(pidof /broadcom/openolt)
        if [ -z ${OPENOLT_PID} ] || [ -z ${DEV_MGMT_DAEMON_PID} ];then

            if [ -z ${DEV_MGMT_DAEMON_PID} ]; then
               LOG "dev_mgmt_daemon processes not available"
            fi

            if [ -z ${OPENOLT_PID} ]; then
                LOG "openolt processes not available"
            fi

            # Reboot OLT so that everything recovers in the right state
            reboot -n
            exit 1
        fi

        sleep ${PID_MONITOR_INTERVAL}

        if [ $(is_olt_in_inband_mode; echo $?) -eq 1 ]; then
            INBAND_IF_IP_ADDR=`ip -o -4 addr list ${INBAND_IF} | awk '{print $4}' | cut -d/ -f1`

            if [ -z ${INBAND_IF_IP_ADDR} ] && [ ${SECONDS} -gt 60 ]; then
                # If the in-band interface does not have an IP for more than 60s, reboot the OLT
                LOG "in-band interface ${INBAND_IF} does not have IP for more than 60s, rebooting OLT"
                reboot -n
                exit 1
            elif [ ${#INBAND_IF_IP_ADDR} -gt 0 ]; then
                # This is case where we have an IP address on the in-band interface

                # Reset timer if the in-band interface has an IP address
                SECONDS=0
            fi
        fi
    done
}

#------------------------------------------------------------------------------
# Function Name: monitor_dev_mgmt_daemon_process
# Description:
#    Monitors dev_mgmt_daemon in an infinite loop. The loop breaks if openolt
#    agent process starts
#
# Globals:
#    None
#
# Arguments:
#    None
#
# Returns:
#
#------------------------------------------------------------------------------
monitor_dev_mgmt_daemon_process() {

    # This is builtin bash variable that tracks the number of seconds
    # elapsed since the shell started. We can reset to 0 and the timer
    # starts from here
    SECONDS=0
    while true; do
        DEV_MGMT_DAEMON_PID=$(pidof /broadcom/dev_mgmt_daemon)
        if [ -z ${DEV_MGMT_DAEMON_PID} ];then
            # Reboot OLT so that everything recovers in the right state
            LOG "dev_mgmt_daemon process crashed or not available in in-band mode of OLT, rebooting OLT"
            reboot -n
        fi

        sleep ${PID_MONITOR_INTERVAL}

        OPENOLT_PID=$(pidof /broadcom/openolt)
        if [ ${OPENOLT_PID} ]; then
            LOG "openolt process has started. start monitoring both dev_mgmt_daemon and openolt processes"
            break
        elif [ ${SECONDS} -ge ${MAX_WAIT_TIMER_FOR_OPENOLT_PROCESS_TO_START} ]; then
            # Typically the openolt process is supposed to start within MAX_WAIT_TIMER_FOR_OPENOLT_PROCESS_TO_START
            # If that does not happen, reboot the OLT.
            LOG "openolt process did not start for more than ${MAX_WAIT_TIMER_FOR_OPENOLT_PROCESS_TO_START} seconds, rebooting OLT"
            reboot -n
            exit 1
        fi
    done
}

#------------------------------------------------------------------------------
# Function Name: is_olt_in_inband_mode
# Description:
#    Checks if OLT is working in in-band mode
#    Presence of in-band startup scripts indicates in-band mode. These scripts
#    are not packaged as part of the debian package or the ONL when OLT is working
#    in out-of-band mode.
#
# Globals:
#    None
#
# Arguments:
#    None
#
# Returns:
#
#------------------------------------------------------------------------------
is_olt_in_inband_mode() {
    ! [ -f "/etc/init.d/start_inband_oltservices.sh" ]
}


# Execution starts here
LOG "---- watchdog started ----"

# Source watchdog configuration
 . /opt/openolt/watchdog.config

if [ ${enable_watchdog} = "yes" ]; then
    LOG "watchdog is enabled"
else
    LOG "watchdog is disabled - exiting"
    exit 0
fi

# If OLT is working in out-of-band start with monitoring only dev_mgmt_daemon process
if [ $(is_olt_in_inband_mode; echo $?) -eq 1 ]; then
    LOG "openolt working in in-band mode, starting to monitor dev_mgmt_daemon process first"
    monitor_dev_mgmt_daemon_process
    # If we are here, that means the openolt process has just started and we now need to
    # monitor both dev_mgmt_daemon and openolt process
else
    sleep ${watchdog_startup_timer} # Allow some time for openolt and dev_mgmt_daemon process to start
    LOG "openolt working in out-of-band mode"
fi

monitor_openolt_and_dev_mgmt_daemon_process