#!/bin/sh
#
# To use:
# 
# 1) Put somewhere convenient and rename "openocd"
# 2) Tweak the OPENOCD_CFG_DIR to point to the location where
#    you keep the configuration file (stm32f3-discovery.cfg).
#    That file will also need to be modified to point to the 
#    other two configuration / procedure files.  Hey, it ain't
#    pretty, but it works.
# 4) Tweak OPENOCD_BIN to specify the path to the openocd
#    daemon executable (version 0.9 or later required for SWD)
# 5) Tweak OPENOCD_DEBUG_ARGS to set the desired debug level. 
#

OPENOCD_CFG_DIR="$HOME/dev/stm32/openocd"
OPENOCD_CFG="${OPENOCD_CFG_DIR}/stm32f3-discovery.cfg"
OPENOCD_ARGS="-f ${OPENOCD_CFG}"
OPENOCD_BIN="/usr/local/bin/openocd"
OPENOCD_DEBUG_ARGS="-d3"
OPENOCD_PID_FILE="/tmp/openocd.pid"

if [ ! -d ${OPENOCD_PATH} ]; then
    echo "OpenOCD path does not exist: ${OPENOCD_PATH}"
    exit 1
fi

if [ ! -x ${OPENOCD_BIN} ]; then
    echo "OpenOCD does not exist: ${OPENOCD_BIN}"
    exit 1
fi

if [ ! -f ${OPENOCD_CFG} ]; then
    echo "OpenOCD config file does not exist: ${OPENOCD_CFG}"
    exit 1
fi

# backgrounded tasks always return 0 so we have to check to 
# make sure the daemon is running before we try to write the
# pid, otherwise we're creating a false paper trail.
start_daemon() {
    cmd=$1
    $cmd &
    OCDPID=$!
    sleep 1
    pid=$(pgrep -f "$OPENOCD_BIN")
    if [ -n "$pid" ]; then
	echo $OCDPID > $OPENOCD_PID_FILE
	echo "OpenOCD daemon started, PID = $OCDPID"
    else
	echo "Trouble starting OpenOCD.  Can't find pid in process table."
    fi
}

case "$1" in
    start)
    echo "Starting OpenOCD."
    start_daemon "$OPENOCD_BIN $OPENOCD_ARGS"
    ;;
    
    debug)
    echo "Starting OpenOCD with $OPENOCD_DEBUG_ARGS."
    start_daemon "$OPENOCD_BIN $OPENOCD_DEBUG_ARGS"
    ;;
    
    stop)
    if [ -f "$OPENOCD_PID_FILE" ]; then
	PID=$(head -n 1 "$OPENOCD_PID_FILE")
    fi
    
    if [ -n "$PID" ]; then
	kill -15 $PID
	sleep 2
	rm -f $PID
    else
	echo "OpenOCD daemon not running (could not find pid)"
    fi
    ;;

    restart)
    $0 stop
    $0 start
    ;;
    
    *)
    echo "Usage: openocd {start|stop|restart}" >&2
    exit 1
    ;;
esac