helper for running qemu

run-qemu

#!/bin/bash

if [ -n "$V" ]; then
    set -x
fi

PORT_BASE=59401

make_port_number() {
    echo $((PORT_BASE + RANDOM % 100))
}

usage() {
    local self
    self=$(basename "$0")
    echo "usage: $self <image-path> <additional-qemu-options>"
    echo
    echo "Environment variables:"
    echo "    SNAPSHOT    defaults, to '-snapshot', passed verbatim to qemu,"
    echo "                optionally set to 'n' to disable snapshot"
    echo "    GUI         defaults to 'n', passed verbatim to qemu,"
    echo "                optionally set to 'y' to enable graphical console"
    echo "    V           enable verbose mode"
    echo "    ARCH        architecture, used in qemu-system-\${ARCH}"
}

case "$1" in
    -h|--help)
        usage
        exit 0
        ;;
esac

IMAGE=$1
shift

if [ -z "$IMAGE" ] || [ ! -e "$IMAGE" ]; then
    echo "error: image path not provided, see --help"
    exit 1
fi

SNAPSHOT=${SNAPSHOT-"-snapshot"}
if [ "$SNAPSHOT" = "n" ]; then
    SNAPSHOT=
fi

GUI=${GUI:-n}
case "$GUI" in
    n)
        GUI_ARGS="-nographic"
        ;;
    spice)
        SPICE_SOCKET=/tmp/vm_spice.$(make_port_number)
        GUI_ARGS="-vga qxl \
            -device virtio-serial-pci
            -device virtserialport,chardev=spicechannel0,name=com.redhat.0 \
            -chardev spicevmc,id=spicechannel0,name=vdagent \
            -spice unix,addr=$SPICE_SOCKET,disable-ticketing"
        ;;
    virtio)
        GUI_ARGS="-vga virtio -display gtk,gl=on"
        ;;
    y)
        GUI_ARGS=
        ;;
    *)
        echo "unsupported GUI option '$GUI'"
        exit 1
        ;;
esac

DISKIF=${DISKIF:-virtio}
NETIF=${NETIF:-virtio-net-pci}

SSH_PORT="${SSH_PORT:-$(make_port_number)}"
SERIAL_PORT=$(make_port_number)
MONITOR_PORT=$(make_port_number)
ARCH=${ARCH:=x86_64}

echo "ports"
echo "   SSH:     ssh -p $SSH_PORT localhost"
echo "   serial:  telnet localhost $SERIAL_PORT"
echo "   monitor: telnet localhost $MONITOR_PORT"
if [ "$GUI" = "spice" ]; then
    echo "   spice:   spice+unix://$SPICE_SOCKET"
fi


exec qemu-system-${ARCH} \
                   -enable-kvm \
                   $SNAPSHOT \
                   -m 2048 \
                   -device ${NETIF},netdev=mynet0 \
                   -netdev user,id=mynet0,hostfwd=tcp:127.0.0.1:${SSH_PORT}-:22 \
                   -serial telnet:127.0.0.1:${SERIAL_PORT},server,nowait \
                   -monitor telnet:127.0.0.1:${MONITOR_PORT},server,nowait \
                   $GUI_ARGS \
                   -object rng-random,filename=/dev/urandom,id=rng0 -device virtio-rng-pci,rng=rng0 \
                   -drive file="$IMAGE",if="$DISKIF",index=0 \
                   "$@"

# -hda "$IMAGE" \
#-drive file="$IMAGE",if=virtio,index=0 \
#