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#!/usr/bin/env python3
# -*- encoding: utf-8 -*-
""" vws - script to control QEMU/KVM virtual workstations """
# pylint: disable=too-many-lines
from configparser import ConfigParser
from argparse import ArgumentParser, Namespace
import fcntl
import socket
import select
import errno
import re
import os
import os.path
import sys
import time
import pwd

VERSION = 0.8
def find_vm(name):
    """ Search and return VM directory """
    search_path = [os.path.join(pwd.getpwuid(os.getuid()).pw_dir, "VWs"),
                   config.get("directories", "SharedVMs"),
                   config.get("directories", "AutostartVMs")]
    for dirname in search_path:
        if not os.access(dirname, os.X_OK):
            continue
        if (name in os.listdir(dirname) and
                os.access(os.path.join(dirname, name, "start"), os.X_OK)):
            return os.path.join(dirname, name)
    raise ValueError("Machine %s not found." % name)


def connect_vm(vm_dir):
    """ Connects to monitor of VM in vm_dir and returns connected socket"""
    sock = socket.socket(socket.AF_UNIX)
    monitor_path = os.path.join(vm_dir, "monitor")
    if not os.access(monitor_path, os.W_OK):
        return None
    try:
        sock.connect(monitor_path)
    except IOError as ex:
        if ex.errno == errno.ECONNREFUSED:
            # virtal machine is not running
            return None
        raise ex
    readfd, dummy_w, dummy_x = select.select([sock], [], [], 0.1)
    if sock in readfd:
        dummy_greeting = sock.recv(1024)
    return sock

def send_command(sock, command):
    """ Sends monitor command to given socket and returns answer """
    fcntl.flock(sock, fcntl.LOCK_EX)
    try:
        # There can be stray (qemu) prompt in the socket. Try to drain
        # it
        try:
            sock.recv(64, socket.MSG_DONTWAIT)
        except socket.error as ex:
            if ex.errno != errno.EAGAIN and ex.errno != errno.EWOULDBLOCK:
                raise ex
        sock.send(command + "\n")
        answer = ""
        while not answer.endswith("(qemu) "):
            chunk = sock.recv(1024)
            if chunk == '':
                raise IOError("Unexpected EOF from monitor")
            answer += chunk
    finally:
        fcntl.flock(sock, fcntl.LOCK_UN)
    return answer

def spiceurl(sock):
    """ Returns spice URI for given (as set of parsed args) VM """
    output = send_command(sock, "info spice")
    url = None
    for line in output.split("\n"):
        if url is not None:
            continue
        idx = line.find("address:")
        if idx != -1:
            url = line[idx+9:]
            if url.startswith('*:'):
                url = socket.getfqdn()+url[1:]
    if url is None:
        if output.rstrip().endswith('(qemu)'):
            return spiceurl(sock)
        print("ERROR parsing 'info spice' output:«%s»" % output, file=sys.stderr)
        return None
    return "spice://" + url.rstrip('\r')



def list_bridges():
    """ Return list of bridge network interfaces present in the system """
    lst = []
    with os.popen(config.get('tools', 'bridge_list'), "r") as f:
        for line in f:
            idx = line.find('\t')
            if idx <= 0:
                continue
            name = line[:idx]
            if name == "bridge name":
                continue
            lst.append(name)
    return lst

def parse_arp(iface):
    """
    Returns map which maps mac addresses to IPs for specified interface"
    """
    addr_map = {}
    pipe = os.popen("%s -n -u %s" % (config.get("tools", "arp"), iface), "r")
    for line in pipe:
        data = line.split()
        mac = data[2]
        if mac == "HWAddress":
            continue
        if mac == iface:
            # Foind line with (incomplete) entry
            continue
        addr_map[data[2]] = data[0]
    return addr_map

def validate_size(size):
    """ Checks if size argument has proper format """
    return re.match('\\d+[KMG]', size) is not None

def get_drives(vm_dir):
    """ Return list of drive files in the VW directory """
    result = []
    with open(vm_dir + "/start") as f:
        for line in f:
            if (re.match("\\s*-drive .*", line) and
                    line.find("media=disk") > -1):
                match = re.search("file=([^,\\s]*)", line)
                if match:
                    result.append(match.group(1))
    return result

def snapshot_mode(sock):
    """ Returns True if VM is running in snapshot mode """
    answer = send_command(sock, "info block")
    return re.search(": /tmp", answer) is not None

def read_netinfo(filename):
    """ Reads network information from start script """
    with open(filename, "r") as f:
        for line in f:
            match = re.search("-net nic,macaddr=(\\S+) -net ([^, ]+)", line)
            if match:
                f = {"mac":match.group(1)}
                if match.group(2) == "user":
                    f["iface"] = "user"
                elif match.group(2) == "bridge":
                    f["iface"] = re.search("br=(\\S+)", line).group(1)
                else:
                    f["iface"] = "unknown"
                return f
    return {"iface":"unknown", "mac":"?", "ip":"?"}
def get_netinfo(sock):
    """ Gets network information from the running VM """
    answer = send_command(sock, "info network")
    match = re.search("bridge\\.0:.*,br=(\\S+).*macaddr=(\\S+)", answer, re.S)
    if match:
        return {"iface":match.group(1), "mac":match.group(2)}
    match = re.search("user.0:.*net=([^,]+).*\n.*macaddr=(\\S+)", answer)
    if match:
        return {"iface":"user", "ip":match.group(1),
                "mac":match.group(2)}
    print(answer, file=sys.stderr)
    return {"iface":"unknown", "ip":"?", "mac":"?", "card":"?"}
#
# command implementation
#

def cmd_spiceuri(options):
    """ vws spiceuri """
    print(spiceurl(options.sock))

def fix_bridge_name(filename):
    """
    Checks if bridge listed in network configuration
    exists on this machine, and replaces it with default one
    from config, if not so
    """
    f = open(filename, "r+")
    data = f.read()
    idx0 = data.find("-net bridge,br=")
    if idx != -1:
        idx = data.find("=", idx0)
        idx += 1
        idx2 = data.find(" ", idx)
        bridgename = data[idx:idx2]
        if not bridgename in list_bridges():
            net = config.get("create options", "net")
            if net == "user":
                data = data[:idx0] + "-net user" + data[idx2:]
            else:
                data = data[:idx] + net + data[idx2:]
            f.seek(0)
            f.write(data)
            f.truncate()
    f.close()

def check_for_snapshot(vmdir):
    """
    Checks if there is snapshot of running vm which should be restored
    Returns either id of this snapshot or None
    """

    nxt = 0
    with os.popen("qemu-img info \"%s\"" %
                  (get_drives(vmdir)[0]), "r") as f:
        for line in f:
            if line == 'Snapshot list:\n':
                nxt = 2
            elif nxt == 2 and line.startswith('ID'):
                nxt = 1
            elif nxt == 1:
                nxt = 0
                snapshot_id = line[:line.index(' ')]
                return snapshot_id
    return None

def make_start_cmdline(options):
    """
    Append options passed from vws commandline to start script
    commandline
    """
    arg = ""
    if options.cdrom:
        arg = " -cdrom " + os.path.abspath(options.cdrom[0])
    if options.snapshot:
        arg = arg+" -snapshot"
    if options.args:
        arg = arg + " " + "".join(options.args)
    if options.password:
        os.environ["SPICE_PASSWORD"] = options.password[0]
    return arg
def cmd_start(options):
    """ vws start """
    if not "DISPLAY" in os.environ:
        # If cannot start GUI just don't do it.
        options.gui = False
    if options.stopped:
        arg = make_start_cmdline(options)
        cwd = os.getcwd()
        os.chdir(options.dir)
        # Check for snapshot
        snapshot_id = check_for_snapshot(options.dir)
        if snapshot_id is not None:
            arg = arg + " -loadvm " + snapshot_id
        # Check for correct brige name
        try:
            os.stat("monitor")
        except OSError:
            # We cannot find monitor socket. So this machine might be
            # never run on this host
            fix_bridge_name("start")
        os.system("./start%s" % arg)
        os.chdir(cwd)
        time.sleep(2)
        options.sock = connect_vm(options.dir)
        if snapshot_id:
            send_command(options.sock, "delvm " + snapshot_id)
    else:
        if options.snapshot or options.args or options.password:
            print("Cannot change qemu options. " +
                  "VM is already running", file=sys.stderr)
        if options.cdrom:
            options.file = options.cdrom[0]
            options.id = None
            cmd_cdrom(options)
    uri = spiceurl(options.sock)
    if options.gui:
        os.system((config.get('tools', 'viewer') + "&") % uri)
    elif not options.stopped:
        print("VM already running use uri %s" % uri, file=sys.stderr)

def cmd_stop(options):
    """ vws stop """
    if snapshot_mode(options.sock) or options.hard:
        try:
            send_command(options.sock, 'quit')
        except IOError as ex:
            # Expect IOError here
            if str(ex).find("EOF from monitor"):
                print("monitor socket closed")
            else:
                raise ex
    else:
        print(send_command(options.sock, 'system_powerdown'))

def cmd_monitor(options):
    """ vws monitor """
    try:
        print("(qemu) ", end="")
        sys.stdout.flush()
        while True:
            readfd, dummy_w, dummy_x = select.select([sys.stdin, options.sock],
                                                     [], [])
            if sys.stdin in readfd:
                cmd = sys.stdin.readline()
                # Check for eof
                if cmd == "":
                    break
                answer = send_command(options.sock, cmd.rstrip())
                idx = answer.index('\n')
                print(answer[idx+1:], end="")
                sys.stdout.flush()
            elif options.sock in readfd:
                print("UNSOLICITED MESSAGE %" +
                      options.sock.readline().rstrip())
    except KeyboardInterrupt:
        print("Keyboard interrupt")

def cmd_reset(options):
    """ vws reset """
    print(send_command(options.sock, 'system_reset'))


def cmd_save(options):
    """ vws save """
    answer = send_command(options.sock, 'savevm')
    if re.search("Error", answer):
        print(answer, file=sys.stderr)
        sys.exit(1)
    else:
        send_command(options.sock, 'quit')

def cmd_cdrom(options):
    """ vws cdrom """
    if options.id  is None:
        # Search for devices which could be interpreted as CDROM
        devlist = send_command(options.sock, "info block")
        for dev in  re.findall("([-\\w]+): [^\n]+\n    Removable device:",
                               devlist):
            if re.search("cd", dev):
                options.id = dev
                break
    if options.id is None:
        print("No CDROM device found among:\n" + devlist, file=sys.stderr)
        return 1
    if options.file == "":
        print("Please specify either --eject or iso image", file=sys.stderr)
        return 1
    if options.file is None:
        answer = send_command(options.sock, "eject " + options.id)
    else:
        answer = send_command(options.sock, "change %s %s" %
                              (options.id, os.path.abspath(options.file)))
    print(answer)
    return 0

def find_usb(options, devices):
    """ Search for pattern or address given in options in the
        given list of devices.
        List should be produced by get_host_devices() or
        get_vm_devices()
    """
    if hasattr("pattern", options):
        for dev in devices:
            if re.search(options.pattern, dev[1]):
                options.address = dev[0]
                break
    elif not hasattr("address", options):
        print("Address or search pattern for device " +
              "is not specified", file=sys.stderr)
        options.sock.close()
        sys.exit(1)
    return options.address

def get_host_devices():
    """ Parses output of lsusb into list of tuples "address" "descr" """
    # pylint: disable=global-statement, invalid-name
    global config
    f = os.popen(config.get('tools', "lsusb"), "r")
    lst = []
    for dev in f:
        match = re.match('Bus (\\d+) Device (\\d+): (.*)$', dev)
        if match:
            if match.group(3).endswith("root hub"):
                continue
            lst.append((match.group(1) + "." + match.group(2), match.group(3)))
    f.close()
    return lst

def get_vm_devices(sock):
    """ Parses output of info usb monitor command into list of devices"""
    answer = send_command(sock, "info usb")
    lst = []
    for dev in answer.split("\n"):
        match = re.match('Device (\\d+\\.\\d+), .*?, Product (.*)$', dev)
        if match:
            lst.append((match.group(1), match.group(2)))
    return lst

def cmd_usb_insert(options):
    """ vws usb insert """
    address = find_usb(options, get_host_devices())
    answer = send_command(options.sock, "usb_add host:%s" % address)
    print(answer)


def cmd_usb_list(_):
    """ vws usb list - just list all host devices """
    for addr, descr in get_host_devices():
        print("%s: %s" % (addr, descr))

def cmd_usb_attached(options):
    """ vws usb attached - list devices assigned to given vm """
    for dev in get_vm_devices(options.sock):
        print("Address %s : %s" % (dev[0], dev[1]))

def cmd_usb_remove(options):
    """ vws usb remove """
    address = find_usb(options, get_vm_devices(options.sock))
    answer = send_command(options.sock, "usb_del %s" % address)
    print(answer)

def make_vm_listing(vmname, dirname, vmtype):
    """ makes dict with vm properties for short index """
    f = {"name":vmname, "type":vmtype}
    sock = connect_vm(dirname)
    if sock is None:
        f.update({"state":"stopped", "uri":"-", "ip":"-"})
        f.update(read_netinfo(os.path.join(dirname, "start")))
    else:
        uri = spiceurl(sock)
        if uri is None:
            f.update({"state":"problem", "uri":"None", "ip":"-"})
            f.update(read_netinfo(os.path.join(dirname, "start")))
        else:
            f["uri"] = uri[uri.rindex(":")+1:]
            f.update(get_netinfo(sock))
            sock.shutdown(socket.SHUT_RDWR)
            sock.close()
            f["state"] = "running"
    return f

def matches(name, patterns):
    """ checks if name matches one of patterns """
    import fnmatch
    for pattern in patterns:
        if fnmatch.fnmatch(name, pattern):
            return True
    return False

def add_ip_address(listing):
    """ Adds IP addresses from ARP into VM listing """
    bridges = set()
    for vminfo in listing:
        if "ip" not in vminfo:
            bridges.add(vminfo["iface"])
    arp_data = {}
    for bridge in bridges:
        arp_data.update(parse_arp(bridge))
    for vminfo in listing:
        if "mac" in vminfo and not "ip" in vminfo:
            if vminfo["mac"] in arp_data:
                vminfo["ip"] = arp_data[vminfo["mac"]]
            else:
                vminfo["ip"] = "-"
def all_vms():
    """
    Returns list of tuples  vmname, vmtype, directory
    for all vms
    """
    search_path = [("private", os.path.join(pwd.getpwuid(os.getuid()).pw_dir,
                                            "VWs")),
                   ("shared", config.get("directories", "SharedVMs")),
                   ("autostart", config.get("directories", "AutostartVMs"))]
    vmlist = []
    for (vmtype, dirname) in search_path:
        if not os.access(dirname, os.X_OK):
            continue
        for vmname in os.listdir(dirname):
            if not os.access(os.path.join(dirname, vmname, "start"), os.X_OK):
                continue
            vmlist.append((vmname, vmtype, os.path.join(dirname, vmname)))
    return vmlist
def cmd_list(options):
    """ vws list """
    count = 0
    maxlen = 0
    vms = []
    for vmname, vmtype, dirname in all_vms():
        if not matches(vmname, options.pattern):
            continue
        count += 1
        if maxlen < len(vmname):
            maxlen = len(vmname)
        if options.state:
            vms.append(make_vm_listing(vmname, dirname, vmtype))
        else:
            vms.append({"name":vmname})
    if options.state:
        add_ip_address(vms)
    for f in sorted(vms, key=lambda x: x["name"]):
        if "state" in f:
            f["name"] = f["name"].ljust(maxlen)
            print(("%(name)s %(state)s   %(type)-9s %(uri)-4s %(iface)-5s " +
                   "%(mac)s %(ip)s ") % f)
        else:
            print(f["name"])
    if not count:
        sys.exit(1)

def cmd_screenshot(options):
    """ vws screenshot """
    from os.path import abspath
    filename = abspath(options.filename)
    print(send_command(options.sock, "screendump " + filename))

def cmd_record(options):
    """ vws record """
    from os.path import abspath
    filename = abspath(options.filename)
    print(send_command(options.sock, "wavcapture " + filename))

def cmd_stoprecord(options):
    """ vws stoprecord """
    answer = send_command(options.sock, "info capture")
    match = re.search('\\[(\\d+)\\]: ', answer)
    if not match:
        print("No sound recording in progress", file=sys.stderr)
        sys.exit(1)
    else:
        print(send_command(options.sock, "stopcapture " + match.group(1)))

def cmd_sendkey(options):
    """ vws sendkey """
    print(send_command(options.sock, "sendkey " + options.keyspec))

def cmd_version(_):
    """ vws cersion """
    print(VERSION)


def cmd_snapshot(options):
    """ vws snapshot - create snapshot """
    if not options.stopped:
        print("Cannot make snapshot of running VW", file=sys.stderr)
        sys.exit(1)
    drives = get_drives(options.dir)
    os.chdir(options.dir)
    newnames = {}
    for i in drives:
        name, ext = os.path.splitext(i)
        newnames[i] = name + "." + options.snapname + ext
        if os.path.exists(newnames[i]):
            print("Snapshot %s already exists", options.snapname,
                  file=sys.stderr)
            return 1
    for i in drives:
        os.rename(i, newnames[i])
        os.system("qemu-img create -f qcow2 -b \"%s\" \"%s\"" %
                  (newnames[i], i))
        os.chmod(i, 0o664)
    return 0

def cmd_snapshots(options):
    """ vws snapshots - list existing snapshots """
    os.chdir(options.dir)
    drives = get_drives(options.dir)
    lst = []
    info = {}
    with os.popen("qemu-img info --backing-chain " + drives[0], "r") as f:
        for line in f:
            if line.find(": ") != -1:
                var, val = line.strip().split(": ")
                if val != "":
                    info[var] = val
            elif line[0] == '\n':
                lst.append(info)
                info = {}
        lst.append(info)
    for snap in lst:
        print("%-30s  %+8s  %+8s" % (snap["image"], snap["virtual size"],
                                     snap["disk size"]))


def get_backing(drive):
    """ find if partucular virtual drive has backing file and returns
        its name
    """
    with os.popen('qemu-img info "%s"' % drive, "r") as f:
        for line in f:
            match = re.match("backing.file: (.*)$", line)
            if match:
                return match.group(1)
    return None

def cmd_revert(options):
    """ reverts to last snapshot:
      Removes latest snapshot images and creates new ones instead
      number of snapshots in the stack is not changed by this command
    """
    if not options.stopped:
        print("Cannot revert running VW to snapshot", file=sys.stderr)
        sys.exit(1)
    os.chdir(options.dir)
    for drive in get_drives(options.dir):
        # Check if first  has backing file
        backing = get_backing(drive)
        if not backing:
            print("Drive %s has no snapshots" % drive, file=sys.stderr)
            continue
        # Unlink current image
        os.unlink(drive)
        # create new image with same backing file
        os.system('qemu-img create -f qcow2 -b "%s" "%s"' % (backing, drive))
        os.chmod(drive, 0o664)

def cmd_commit(options):
    """
    Commits last snapshot changes into it's backing file
    There would be one snapshot less for virtual machine
    """
    if options.stopped:
        #
        # Stoppend vm - last snapshot is commited into its backing file.
        # Backing file is made current drive image
        #
        os.chdir(options.dir)
        found = 0
        for drive in get_drives(options.dir):
            backing = get_backing(drive)
            if backing is None:
                continue
            found = 1
            os.system('qemu-img commit "%s"'%drive)
            os.unlink(drive)
            os.rename(backing, drive)
        if not found:
            print("No snapshots exist for this VM", file=sys.stderr)
            sys.exit(1)
    else:
        if snapshot_mode(options.sock):
            send_command(options.sock, "commit")
        else:
            print("VM is not running in snapshot mode", file=sys.stderr)
            sys.exit(1)

def cmd_autostart(_):
    """
    Starts all VMs which are in the autostart directory
    """
    dirname = config.get("directories", "AutostartVMs")
    userinfo = pwd.getpwnam(config.get("permissions", "autostart_user"))
    if not userinfo:
        print("User %s doesn't exists %s" %
              config.get("permissions", "autostart_user"), file=sys.stderr)
        sys.exit(1)
    os.setgid(userinfo.pw_gid)
    os.setuid(userinfo.pw_uid)
    if not os.access(dirname, os.R_OK):
        return
    for name in os.listdir(dirname):
        if not os.access(os.path.join(dirname, name, "start"), os.X_OK):
            continue
        machine_dir = os.path.join(dirname, name)
        sock = connect_vm(machine_dir)
        if sock:
            # Machine already running
            sock.shutdown(socket.SHUT_RDWR)
            sock.close()
            continue
        start_opts = Namespace(machine=name, command='start',
                               dir=machine_dir, snapshot=False,
                               stopped=True, password=None,
                               args="", gui=False, cdrom=None)
        try:
            cmd_start(start_opts)
            print(name+" ", end="")
        finally:
            # pylint: disable=no-member
            if hasattr(start_opts, "sock") and start_opts.sock:
                start_opts.sock.shutdown(socket.SHUT_RDWR)
    print("")

def cmd_shutdown(options):
    """ Search for all running machines and stops all of them """
    dirlist = [config.get("directories", "AutostartVMs"),
               config.get("directories", "SharedVms")]
    if os.getresuid()[1] == 0:
        import grp
        dirlist += map(lambda x: os.path.expanduser("~"+x)+"/VWs",
                       grp.getgrnam(config.get("permissions",
                                               "vm_group")).gr_mem)
    else:
        dirlist.append(os.path.expanduser("~")+"/VWs")
    count = 1 #Fake positive values for there is not postcondition loop in the python
    forced_finish = time.time() + options.timeout
    while count > 0:
        count = 0
        if time.time() < forced_finish:
            command = "system_powerdown"
        else:
            command = "quit"
        for  _, _, dirname in all_vms():
            sock = connect_vm(dirname)
            if not sock:
                # not running
                continue
            count += 1
            try:
                send_command(sock, command)
            except IOError:
                #When hard_stopping,socket might be closed by way
                sock.shutdown(socket.SHUT_RDWR)
                sock.close()
        if not options.wait:
            return
        if count > 0:
            time.sleep(10)

TEMPLATE = """#!/bin/sh
# Get machine name from current directory name
NAME=$(basename $(pwd))
# if remote access is enabled, then there should be
# SPICE_PASSWORD=password
QEMU_AUDIO_DRV=spice
export QEMU_AUDIO_DRV
if [ -n "$SPICE_PASSWORD" ]; then
   SPICE_AUTH="password=$SPICE_PASSWORD"
else
   SPICE_AUTH="disable-ticketing,addr=127.0.0.1"
fi
SPICE_PORT=$(find_free_port 5900)
if [ "$1" = '-cdrom' ]; then
	shift
	CDROM=",file=$1"
	shift
fi
#set umask to make machine group-accessable
umask 002
{qemubinary} -name $NAME {accel} \\
-m {memory} \\
{drive} \\
{cdrom}$CDROM \\
{rtc}{net} \\
{usb} \\
{sound} \\
-chardev socket,server,nowait,path=monitor,id=monitor \\
-mon chardev=monitor,mode=readline \\
-vga {vga} \\
-spice port=$SPICE_PORT,$SPICE_AUTH \\
-device virtio-serial -chardev spicevmc,id=vdagent,name=vdagent \\
-device virtserialport,chardev=vdagent,name=com.redhat.spice.0 \\
-device ich9-usb-ehci1,id=usb \\
-device ich9-usb-uhci1,masterbus=usb.0,firstport=0,multifunction=on \\
-chardev spicevmc,name=usbredir,id=usbredirchardev1 \\
-device usb-redir,chardev=usbredirchardev1,id=usbredirdev1 \\
-daemonize -pidfile pid {extraargs}
chgrp {group} monitor pid
chmod 0660 monitor pid
"""

BADSIZE = "Invalid size of %s specifed %s. Should have K, M or G suffix"
NOACCEL = "KVM acceleration disabled due to "

def cmd_create(parsed_args):
    """ vws create - create new VM """
    if not parsed_args.image and not validate_size(parsed_args.size):
        raise ValueError(BADSIZE % ("disk", parsed_args.size))
    if not validate_size(parsed_args.mem):
        raise ValueError(BADSIZE % ("memory", parsed_args.size))
    drivename = "drive0.qcow2"
    options = {'qemubinary':'qemu-system-x86_64',
               "accel":"-enable-kvm",
               "memory":"1024M",
               "vga":'qxl',
               "drive":"-drive media=disk,index=0,if={interface},file={image}",
               "cdrom":"-drive media=cdrom,index=2,if=ide",
               "sound":"-soundhw hda",
               "group":config.get("permissions", "vm_group"),
               "usb":"-usb",
               "rtc":"",
               "extraargs":"${1:+\"$@\"}"}
    macaddr = ":".join(["%02x" % ord(x) for x in  chr(0x52) + os.urandom(5)])
    if parsed_args.shared:
        machinedir = os.path.join(config.get("directories", "SharedVMs"),
                                  parsed_args.machine)
        dirmode = 0o775
    else:
        machinedir = os.path.join(pwd.getpwuid(os.getuid()).pw_dir, "VWs",
                                  parsed_args.machine)
        dirmode = 0o775
    if parsed_args.net != 'user':
        bridges = list_bridges()
        if not parsed_args.net in bridges:
            raise ValueError("No such bridge %s. Available ones %s" %
                             (parsed_args.net, ", ".join(bridges)))
        options["net"] = ("-net nic,macaddr=%s -net bridge,br=%s" %
                          (macaddr, parsed_args.net))
    else:
        options["net"] = "-net nic,macaddr=%s -net user" % (macaddr,)
    options["qemubinary"] = 'qemu-system-' + parsed_args.arch
    options["vga"] = parsed_args.vga
    if not parsed_args.arch in ('i386', 'x86_64'):
        print(NOACCEL + "target architecture", file=sys.stderr)
        options.accel = ''
    elif not os.access("/dev/kvm", os.W_OK):
        print(NOACCEL + "unavailability on the host system", file=sys.stderr)
        options.accel = ''

    if not parsed_args.usb:
        options["usb"] = ''

    if not parsed_args.sound:
        options["sound"] = ''
    else:
        options["sound"] = '-soundhw ' + parsed_args.sound

    options["memory"] = parsed_args.mem
    if parsed_args.localtime:
        options["rtc"] = "-rtc base=localtime,clock=host \\\n"

    if os.path.exists(machinedir):
        if os.path.exists(os.path.join(machinedir, "start")):
            raise OSError("Virtual Worstation %s already exists" %
                          parsed_args.machine)
        else:
            raise OSError("Cannot create VW directory, " +
                          "something on the way")
    #  Creating directory for VM
    os.makedirs(machinedir, dirmode)
    parsed_args.dir = machinedir
    if parsed_args.shared:
        import grp
        gid = grp.getgrnam(config.get("permissions", "vm_group")).gr_gid
        uid = os.getuid()
        os.chown(machinedir, uid, gid)
        if config.getboolean("permissions", "setgid_vm"):
            os.chmod(machinedir, 0o2775)
    driveopts = {"interface":parsed_args.diskif, "image":drivename}
    if parsed_args.install:
        install_image = os.path.abspath(parsed_args.install)

    if parsed_args.image:
        # Copying image file
        print("Copying %s to %s" %
              (parsed_args.image, os.path.join(machinedir, drivename)),
              file=sys.stderr)
        os.system("qemu-img convert -O qcow2 -p %s %s" %
                  (parsed_args.image,
                   os.path.join(machinedir, drivename)))
        os.chdir(machinedir)
    else:
        print("Creating new image file of %s" % parsed_args.size,
              file=sys.stderr)
        os.chdir(machinedir)
        os.system("qemu-img create -f qcow2 %s %s" %
                  (drivename, parsed_args.size))
    os.chmod(drivename, 0o664)
    options["drive"] = options["drive"].format(**driveopts)

    if hasattr(parsed_args, "debug") and parsed_args.debug:
        print(repr(driveopts), repr(options["drive"]))
        print(repr(options))
    with open("start", "w") as script:
        script.write(TEMPLATE.format(**options))
    os.chmod('start', dirmode)
    # If installation media is specified vws start for new vm
    if parsed_args.install:
        start_opts = Namespace(machine=parsed_args.machine, password=None,
                               command='start', cdrom=[install_image],
                               dir=machinedir, stopped=True, snapshot=False,
                               args="", gui=True)
        try:
            cmd_start(start_opts)
        finally:
            # pylint: disable=no-member
            if hasattr(start_opts, "sock"):
                start_opts.sock.shutdown(socket.SHUT_RDWR)

#
# Utility functions for arg parsing
#
def new_command(cmd_parser, name, **kwargs):
    """
    Adds a subparser and adds a machine name argument to it
    """
    parser = cmd_parser.add_parser(name, **kwargs)
    parser.add_argument('machine', type=str, help='name of vm to operate on')
    return parser
#
# prepare defaults for config
#


config = ConfigParser(interpolation=None) # pylint: disable=invalid-name
def config_defaults(conf):
    """ Set default values for config options """
    arch = os.uname()[4]
    if re.match("i[3-9]86", arch):
        arch = "i386"
    elif arch.startswith("arm"):
        arch = "arm"
    conf.read_dict({'directories':{'SharedVMs':'/var/cache/vws/shared',
                                   'AutoStartVMs':'/var/cache/vws/autostart'},
                    'create options':{'net':'user', 'size':'20G', 'mem':'1G',
                                      'diskif':'virtio', 'sound':'hda',
                                      'arch':arch, 'vga':'qxl'},
                    'tools':{'viewer':'remote-viewer %s',
                             'bridge_list':'/sbin/brctl show',
                             'lsusb':'lsusb',
                             'arp':'/usr/sbin/arp'},
                    'permissions':{'vm_group':'kvm',
                                   'autostart_user':'root',
                                   'setgid_vm':'yes'}})

def read_config(conf):
    """ Read configration files """
    if os.getuid() != 0:
        conf.read(['/etc/vws.conf',
                   os.path.join(pwd.getpwuid(os.getuid()).pw_dir, '.vwsrc')])
    else:
        conf.read(['/etc/vws.conf'])
def main():
    """ Parse an arguments and execute everything """
    global config
    config_defaults(config)
    read_config(config)
    # Parse argument
    args = ArgumentParser(description="Manage Virtual Workstations")
    cmds = args.add_subparsers(dest='command', help="sub-command help")
    p = cmds.add_parser("list", help="List existing VWs",
                        description="List existing VWs")
    p.add_argument("-l", "--state", const=True, default=False, dest='state',
                   action='store_const', help='Show state of the machine')
    p.add_argument("--usb", action='store_const', const=True, default=False,
                   dest='usb', help='Show connected USB devices')
    p.add_argument("pattern", nargs='*', default='*', help="Name patterns")
    p = cmds.add_parser("version", help="show vws version")
    p = cmds.add_parser("autostart",
                        help="Autostart all VMs marked as autostartable")
    p = cmds.add_parser("shutdown", help="shut down all running VMs")
    p.add_argument("--wait", help="wait until all machines would be shoutdown",
                   action="store_const", const=True, default=False, dest="wait")
    p.add_argument("--timeout", type=int, default=90,
                   help="how long to way for VMs shutdown before forcing it off")
    # Power management
    p = new_command(cmds, 'start', help='Start VW and connect to console',
                    description="Start VW if not running and connect " +
                    "to the console")
    p.add_argument('--no-gui', dest='gui', action='store_const', const=False,
                   default=True, help='do not open console window')
    p.add_argument('--cdrom', metavar='filename.iso', dest='cdrom', nargs=1,
                   help='connect specified iso image to VMs cdrom on start')
    p.add_argument('--args', metavar='string', dest='args', nargs=1, default="",
                   help="Specify extra QEMU options")
    p.add_argument("--snapshot", action='store_const', const=True, default=False,
                   help="Run without modifying disk image")
    p.add_argument("--password", metavar='string', dest='password', nargs=1,
                   default=None, help="Set password for remote spice connection")
    p = new_command(cmds, 'stop', help='Shut down virtual machine',
                    description="Terminate the VW, gracefully or ungracefully")
    p.add_argument('--hard', help='Power off immediately', action='store_const',
                   dest='hard', const=True, default=False)
    new_command(cmds, 'save', help='Save VW state and stop emulation',
                description="Save VW state and stop emulation")
    new_command(cmds, 'reset', help='Reboot a guest OS',
                description="Reboot othe guuest OS")
    # Removable devices management
    p = new_command(cmds, 'cdrom', help='manage CDROM Drive',
                    description='"insert" an ISO image into emulated CD-ROM ' +
                    "or eject it")
    p.add_argument('--id', type=str, default=None,
                   help='Identifier of CDROM drive if VM has more than one')
    p.add_argument('file', nargs="?", default='',
                   help='ISO image or special file to connect to drive')
    p.add_argument('--eject', dest='file', action='store_const', const=None)
    usb = cmds.add_parser('usb', help='manage USB devices'
                         ).add_subparsers(dest='subcommand',
                                          help='manage USB devices')
    p = new_command(usb, 'insert', help='attach device to the virtual machine')
    p.add_argument('pattern', help='Pattern of device name to look up in lsusb')
    p.add_argument('--address', type=str, dest='address', nargs=1,
                   help='exact address bus:device')
    p = new_command(usb, 'remove', help='detach connected usb device')
    p.add_argument('pattern', help='Pattern of device name to look up in lsusb')
    p.add_argument('--address', type=str, dest='address', nargs=1,
                   help='exact address bus:device')
    p = new_command(usb, 'attached', help='list devices attached to vm')
    usb.add_parser('list', help='list devices available in the host system')
    # Snapshot management
    p = new_command(cmds, 'snapshot', help='Create new snapshot')
    p.add_argument('snapname', help='snapshot name')
    p = new_command(cmds, 'revert', help='Revert to snapshot')
    p.add_argument('snapname', help='name of snapshot to revert to')
    p = new_command(cmds, 'commit',
                    help='Commit snapshot changes into backing file')
    p = new_command(cmds, 'snapshots', help='List existing snapshots')
    # Screenshoits and recording
    p = new_command(cmds, 'screenshot', help='take a screenshot')
    p.add_argument('filename', help='PPM image filename to write screenshot to')
    p = new_command(cmds, 'record', help='Record audio output from VM')
    p.add_argument('filename', help='wav file to record autdio to')
    new_command(cmds, 'stoprecord', help='stop recording audio')
    p = new_command(cmds, 'sendkey', help='Send a keystroke to VM')
    p.add_argument('keyspec', help='key specification like ctrl-alt-delete')
    # Create new VM
    p = new_command(cmds, 'create', help="Create new VW")
    p.add_argument("--no-usb", help="Disable USB controller", action='store_const',
                   const=False, default=True, dest="usb")
    p.add_argument("--size", metavar='size', help="Size of primary disk images",
                   dest="size", default=config.get('create options', 'size'))
    p.add_argument("--arch", metavar='cputype', help="Emulated architecture",
                   dest="arch", default=config.get('create options', 'arch'))
    p.add_argument("--no-sound", help="Disable sound card", action='store_const',
                   const=None, default=config.get('create options', 'sound'),
                   dest="sound")
    p.add_argument('--localtime', action='store_const',
                   help="Show system clock as local time, not UTC to guest OS",
                   const=True, default=False, dest='localtime')
    p.add_argument("--sound", metavar='cardtype', dest='sound',
                   help="Specify sound card type",
                   default=config.get('create options', 'sound'))
    p.add_argument("--vga", metavar='cardtype',
                   help="specify video card type (cirrus,std,vmware,qxl) " +
                   "default " + config.get('create options', 'vga',),
                   dest="vga", default=config.get('create options', 'vga'))
    p.add_argument("--net", help="Network - 'user' or bridge name",
                   dest='net', default=config.get('create options', 'net'))
    p.add_argument("--mem", metavar='size', help="Size of memory",
                   dest="mem", default=config.get('create options', 'mem'))
    p.add_argument("--diskif", metavar='interface-type',
                   help="Disk interface (virtio, scsi, ide)",
                   choices=['virtio', 'scsi', 'ide'], dest="diskif",
                   default=config.get('create options', 'diskif'))
    p.add_argument('--shared', help='Create shared VW instead of private one',
                   action='store_const', const=True, dest='shared',
                   default=False)
    p.add_argument('--image', metavar='filename', dest='image', default=None,
                   help='Existing disk image to import')
    p.add_argument('--install', metavar='filename.iso', dest='install',
                   help='ISO image to install OS from', default=None)
    # Miscellenia
    p = new_command(cmds, 'monitor',
                    help='connect stdin/stdout to monitor of VM')
    p = new_command(cmds,
                    'spiceuri', help='Output spice URI of machine')

    parsed_args = args.parse_args(sys.argv[1:])

    os.umask(0o002)
    # Create command is totally different, so it is handled separately
    if parsed_args.command == 'create':
        try:
            cmd_create(parsed_args)
        except Exception as ex:
            print(str(ex), file=sys.stderr)
            if hasattr(parsed_args, "dir"):
                import shutil
                shutil.rmtree(parsed_args.dir)
                sys.exit(1)
        sys.exit(0)

    if parsed_args.command is None:
        args.print_help()
        sys.exit(0)
    funcname = "cmd_" + parsed_args.command
    if hasattr(parsed_args, "subcommand"):
        funcname += "_" + parsed_args.subcommand
    try:
        func = globals()[funcname]
    except KeyError:
        print("Operation %s is not implemented" % funcname, file=sys.stderr)
        sys.exit(3)

    parsed_args.stopped = False
    stopped_vm_commands = ['start', 'snapshot', 'revert', 'commit', 'snapshots']
    if hasattr(parsed_args, 'machine'):
        parsed_args.dir = find_vm(parsed_args.machine)
        parsed_args.sock = connect_vm(parsed_args.dir)
        if parsed_args.sock is None:
            if not parsed_args.command in stopped_vm_commands:
                print("Virtual machine %s is not running." % parsed_args.machine,
                      file=sys.stderr)
                sys.exit(1)
            else:
                parsed_args.stopped = True

    try:
        func(parsed_args)
    finally:
        if hasattr(parsed_args, 'sock') and parsed_args.sock is not None:
            parsed_args.sock.shutdown(socket.SHUT_RDWR)
            parsed_args.sock.close()

main()