xref: /openbmc/qemu/tests/vm/basevm.py (revision 954a6c4f)
1#
2# VM testing base class
3#
4# Copyright 2017-2019 Red Hat Inc.
5#
6# Authors:
7#  Fam Zheng <famz@redhat.com>
8#  Gerd Hoffmann <kraxel@redhat.com>
9#
10# This code is licensed under the GPL version 2 or later.  See
11# the COPYING file in the top-level directory.
12#
13
14import os
15import re
16import sys
17import socket
18import logging
19import time
20import datetime
21import subprocess
22import hashlib
23import argparse
24import atexit
25import tempfile
26import shutil
27import multiprocessing
28import traceback
29import shlex
30
31from qemu.machine import QEMUMachine
32from qemu.utils import get_info_usernet_hostfwd_port, kvm_available
33
34SSH_KEY_FILE = os.path.join(os.path.dirname(__file__),
35               "..", "keys", "id_rsa")
36SSH_PUB_KEY_FILE = os.path.join(os.path.dirname(__file__),
37                   "..", "keys", "id_rsa.pub")
38
39# This is the standard configuration.
40# Any or all of these can be overridden by
41# passing in a config argument to the VM constructor.
42DEFAULT_CONFIG = {
43    'cpu'             : "max",
44    'machine'         : 'pc',
45    'guest_user'      : "qemu",
46    'guest_pass'      : "qemupass",
47    'root_user'       : "root",
48    'root_pass'       : "qemupass",
49    'ssh_key_file'    : SSH_KEY_FILE,
50    'ssh_pub_key_file': SSH_PUB_KEY_FILE,
51    'memory'          : "4G",
52    'extra_args'      : [],
53    'qemu_args'       : "",
54    'dns'             : "",
55    'ssh_port'        : 0,
56    'install_cmds'    : "",
57    'boot_dev_type'   : "block",
58    'ssh_timeout'     : 1,
59}
60BOOT_DEVICE = {
61    'block' :  "-drive file={},if=none,id=drive0,cache=writeback "\
62               "-device virtio-blk,drive=drive0,bootindex=0",
63    'scsi'  :  "-device virtio-scsi-device,id=scsi "\
64               "-drive file={},format=raw,if=none,id=hd0 "\
65               "-device scsi-hd,drive=hd0,bootindex=0",
66}
67class BaseVM(object):
68
69    envvars = [
70        "https_proxy",
71        "http_proxy",
72        "ftp_proxy",
73        "no_proxy",
74    ]
75
76    # The script to run in the guest that builds QEMU
77    BUILD_SCRIPT = ""
78    # The guest name, to be overridden by subclasses
79    name = "#base"
80    # The guest architecture, to be overridden by subclasses
81    arch = "#arch"
82    # command to halt the guest, can be overridden by subclasses
83    poweroff = "poweroff"
84    # Time to wait for shutdown to finish.
85    shutdown_timeout_default = 30
86    # enable IPv6 networking
87    ipv6 = True
88    # This is the timeout on the wait for console bytes.
89    socket_timeout = 120
90    # Scale up some timeouts under TCG.
91    # 4 is arbitrary, but greater than 2,
92    # since we found we need to wait more than twice as long.
93    tcg_timeout_multiplier = 4
94    def __init__(self, args, config=None):
95        self._guest = None
96        self._genisoimage = args.genisoimage
97        self._build_path = args.build_path
98        self._efi_aarch64 = args.efi_aarch64
99        self._source_path = args.source_path
100        # Allow input config to override defaults.
101        self._config = DEFAULT_CONFIG.copy()
102
103        # 1GB per core, minimum of 4. This is only a default.
104        mem = max(4, args.jobs)
105        self._config['memory'] = f"{mem}G"
106
107        if config != None:
108            self._config.update(config)
109        self.validate_ssh_keys()
110        self._tmpdir = os.path.realpath(tempfile.mkdtemp(prefix="vm-test-",
111                                                         suffix=".tmp",
112                                                         dir="."))
113        atexit.register(shutil.rmtree, self._tmpdir)
114        # Copy the key files to a temporary directory.
115        # Also chmod the key file to agree with ssh requirements.
116        self._config['ssh_key'] = \
117            open(self._config['ssh_key_file']).read().rstrip()
118        self._config['ssh_pub_key'] = \
119            open(self._config['ssh_pub_key_file']).read().rstrip()
120        self._ssh_tmp_key_file = os.path.join(self._tmpdir, "id_rsa")
121        open(self._ssh_tmp_key_file, "w").write(self._config['ssh_key'])
122        subprocess.check_call(["chmod", "600", self._ssh_tmp_key_file])
123
124        self._ssh_tmp_pub_key_file = os.path.join(self._tmpdir, "id_rsa.pub")
125        open(self._ssh_tmp_pub_key_file,
126             "w").write(self._config['ssh_pub_key'])
127
128        self.debug = args.debug
129        self._console_log_path = None
130        if args.log_console:
131                self._console_log_path = \
132                         os.path.join(os.path.expanduser("~/.cache/qemu-vm"),
133                                      "{}.install.log".format(self.name))
134        self._stderr = sys.stderr
135        self._devnull = open(os.devnull, "w")
136        if self.debug:
137            self._stdout = sys.stdout
138        else:
139            self._stdout = self._devnull
140        netdev = "user,id=vnet,hostfwd=:127.0.0.1:{}-:22"
141        self._args = [ \
142            "-nodefaults", "-m", self._config['memory'],
143            "-cpu", self._config['cpu'],
144            "-netdev",
145            netdev.format(self._config['ssh_port']) +
146            (",ipv6=no" if not self.ipv6 else "") +
147            (",dns=" + self._config['dns'] if self._config['dns'] else ""),
148            "-device", "virtio-net-pci,netdev=vnet",
149            "-vnc", "127.0.0.1:0,to=20"]
150        if args.jobs and args.jobs > 1:
151            self._args += ["-smp", "%d" % args.jobs]
152        if kvm_available(self.arch):
153            self._shutdown_timeout = self.shutdown_timeout_default
154            self._args += ["-enable-kvm"]
155        else:
156            logging.info("KVM not available, not using -enable-kvm")
157            self._shutdown_timeout = \
158                self.shutdown_timeout_default * self.tcg_timeout_multiplier
159        self._data_args = []
160
161        if self._config['qemu_args'] != None:
162            qemu_args = self._config['qemu_args']
163            qemu_args = qemu_args.replace('\n',' ').replace('\r','')
164            # shlex groups quoted arguments together
165            # we need this to keep the quoted args together for when
166            # the QEMU command is issued later.
167            args = shlex.split(qemu_args)
168            self._config['extra_args'] = []
169            for arg in args:
170                if arg:
171                    # Preserve quotes around arguments.
172                    # shlex above takes them out, so add them in.
173                    if " " in arg:
174                        arg = '"{}"'.format(arg)
175                    self._config['extra_args'].append(arg)
176
177    def validate_ssh_keys(self):
178        """Check to see if the ssh key files exist."""
179        if 'ssh_key_file' not in self._config or\
180           not os.path.exists(self._config['ssh_key_file']):
181            raise Exception("ssh key file not found.")
182        if 'ssh_pub_key_file' not in self._config or\
183           not os.path.exists(self._config['ssh_pub_key_file']):
184               raise Exception("ssh pub key file not found.")
185
186    def wait_boot(self, wait_string=None):
187        """Wait for the standard string we expect
188           on completion of a normal boot.
189           The user can also choose to override with an
190           alternate string to wait for."""
191        if wait_string is None:
192            if self.login_prompt is None:
193                raise Exception("self.login_prompt not defined")
194            wait_string = self.login_prompt
195        # Intentionally bump up the default timeout under TCG,
196        # since the console wait below takes longer.
197        timeout = self.socket_timeout
198        if not kvm_available(self.arch):
199            timeout *= 8
200        self.console_init(timeout=timeout)
201        self.console_wait(wait_string)
202
203    def _download_with_cache(self, url, sha256sum=None, sha512sum=None):
204        def check_sha256sum(fname):
205            if not sha256sum:
206                return True
207            checksum = subprocess.check_output(["sha256sum", fname]).split()[0]
208            return sha256sum == checksum.decode("utf-8")
209
210        def check_sha512sum(fname):
211            if not sha512sum:
212                return True
213            checksum = subprocess.check_output(["sha512sum", fname]).split()[0]
214            return sha512sum == checksum.decode("utf-8")
215
216        cache_dir = os.path.expanduser("~/.cache/qemu-vm/download")
217        if not os.path.exists(cache_dir):
218            os.makedirs(cache_dir)
219        fname = os.path.join(cache_dir,
220                             hashlib.sha1(url.encode("utf-8")).hexdigest())
221        if os.path.exists(fname) and check_sha256sum(fname) and check_sha512sum(fname):
222            return fname
223        logging.debug("Downloading %s to %s...", url, fname)
224        subprocess.check_call(["wget", "-c", url, "-O", fname + ".download"],
225                              stdout=self._stdout, stderr=self._stderr)
226        os.rename(fname + ".download", fname)
227        return fname
228
229    def _ssh_do(self, user, cmd, check):
230        ssh_cmd = ["ssh",
231                   "-t",
232                   "-o", "StrictHostKeyChecking=no",
233                   "-o", "UserKnownHostsFile=" + os.devnull,
234                   "-o",
235                   "ConnectTimeout={}".format(self._config["ssh_timeout"]),
236                   "-p", str(self.ssh_port), "-i", self._ssh_tmp_key_file,
237                   "-o", "IdentitiesOnly=yes"]
238        # If not in debug mode, set ssh to quiet mode to
239        # avoid printing the results of commands.
240        if not self.debug:
241            ssh_cmd.append("-q")
242        for var in self.envvars:
243            ssh_cmd += ['-o', "SendEnv=%s" % var ]
244        assert not isinstance(cmd, str)
245        ssh_cmd += ["%s@127.0.0.1" % user] + list(cmd)
246        logging.debug("ssh_cmd: %s", " ".join(ssh_cmd))
247        r = subprocess.call(ssh_cmd)
248        if check and r != 0:
249            raise Exception("SSH command failed: %s" % cmd)
250        return r
251
252    def ssh(self, *cmd):
253        return self._ssh_do(self._config["guest_user"], cmd, False)
254
255    def ssh_root(self, *cmd):
256        return self._ssh_do(self._config["root_user"], cmd, False)
257
258    def ssh_check(self, *cmd):
259        self._ssh_do(self._config["guest_user"], cmd, True)
260
261    def ssh_root_check(self, *cmd):
262        self._ssh_do(self._config["root_user"], cmd, True)
263
264    def build_image(self, img):
265        raise NotImplementedError
266
267    def exec_qemu_img(self, *args):
268        cmd = [os.environ.get("QEMU_IMG", "qemu-img")]
269        cmd.extend(list(args))
270        subprocess.check_call(cmd)
271
272    def add_source_dir(self, src_dir):
273        name = "data-" + hashlib.sha1(src_dir.encode("utf-8")).hexdigest()[:5]
274        tarfile = os.path.join(self._tmpdir, name + ".tar")
275        logging.debug("Creating archive %s for src_dir dir: %s", tarfile, src_dir)
276        subprocess.check_call(["./scripts/archive-source.sh", tarfile],
277                              cwd=src_dir, stdin=self._devnull,
278                              stdout=self._stdout, stderr=self._stderr)
279        self._data_args += ["-drive",
280                            "file=%s,if=none,id=%s,cache=writeback,format=raw" % \
281                                    (tarfile, name),
282                            "-device",
283                            "virtio-blk,drive=%s,serial=%s,bootindex=1" % (name, name)]
284
285    def boot(self, img, extra_args=[]):
286        boot_dev = BOOT_DEVICE[self._config['boot_dev_type']]
287        boot_params = boot_dev.format(img)
288        args = self._args + boot_params.split(' ')
289        args += self._data_args + extra_args + self._config['extra_args']
290        logging.debug("QEMU args: %s", " ".join(args))
291        qemu_path = get_qemu_path(self.arch, self._build_path)
292
293        # Since console_log_path is only set when the user provides the
294        # log_console option, we will set drain_console=True so the
295        # console is always drained.
296        guest = QEMUMachine(binary=qemu_path, args=args,
297                            console_log=self._console_log_path,
298                            drain_console=True)
299        guest.set_machine(self._config['machine'])
300        guest.set_console()
301        try:
302            guest.launch()
303        except:
304            logging.error("Failed to launch QEMU, command line:")
305            logging.error(" ".join([qemu_path] + args))
306            logging.error("Log:")
307            logging.error(guest.get_log())
308            logging.error("QEMU version >= 2.10 is required")
309            raise
310        atexit.register(self.shutdown)
311        self._guest = guest
312        # Init console so we can start consuming the chars.
313        self.console_init()
314        usernet_info = guest.qmp("human-monitor-command",
315                                 command_line="info usernet").get("return")
316        self.ssh_port = get_info_usernet_hostfwd_port(usernet_info)
317        if not self.ssh_port:
318            raise Exception("Cannot find ssh port from 'info usernet':\n%s" % \
319                            usernet_info)
320
321    def console_init(self, timeout = None):
322        if timeout == None:
323            timeout = self.socket_timeout
324        vm = self._guest
325        vm.console_socket.settimeout(timeout)
326        self.console_raw_path = os.path.join(vm._temp_dir,
327                                             vm._name + "-console.raw")
328        self.console_raw_file = open(self.console_raw_path, 'wb')
329
330    def console_log(self, text):
331        for line in re.split("[\r\n]", text):
332            # filter out terminal escape sequences
333            line = re.sub("\x1b\[[0-9;?]*[a-zA-Z]", "", line)
334            line = re.sub("\x1b\([0-9;?]*[a-zA-Z]", "", line)
335            # replace unprintable chars
336            line = re.sub("\x1b", "<esc>", line)
337            line = re.sub("[\x00-\x1f]", ".", line)
338            line = re.sub("[\x80-\xff]", ".", line)
339            if line == "":
340                continue
341            # log console line
342            sys.stderr.write("con recv: %s\n" % line)
343
344    def console_wait(self, expect, expectalt = None):
345        vm = self._guest
346        output = ""
347        while True:
348            try:
349                chars = vm.console_socket.recv(1)
350                if self.console_raw_file:
351                    self.console_raw_file.write(chars)
352                    self.console_raw_file.flush()
353            except socket.timeout:
354                sys.stderr.write("console: *** read timeout ***\n")
355                sys.stderr.write("console: waiting for: '%s'\n" % expect)
356                if not expectalt is None:
357                    sys.stderr.write("console: waiting for: '%s' (alt)\n" % expectalt)
358                sys.stderr.write("console: line buffer:\n")
359                sys.stderr.write("\n")
360                self.console_log(output.rstrip())
361                sys.stderr.write("\n")
362                raise
363            output += chars.decode("latin1")
364            if expect in output:
365                break
366            if not expectalt is None and expectalt in output:
367                break
368            if "\r" in output or "\n" in output:
369                lines = re.split("[\r\n]", output)
370                output = lines.pop()
371                if self.debug:
372                    self.console_log("\n".join(lines))
373        if self.debug:
374            self.console_log(output)
375        if not expectalt is None and expectalt in output:
376            return False
377        return True
378
379    def console_consume(self):
380        vm = self._guest
381        output = ""
382        vm.console_socket.setblocking(0)
383        while True:
384            try:
385                chars = vm.console_socket.recv(1)
386            except:
387                break
388            output += chars.decode("latin1")
389            if "\r" in output or "\n" in output:
390                lines = re.split("[\r\n]", output)
391                output = lines.pop()
392                if self.debug:
393                    self.console_log("\n".join(lines))
394        if self.debug:
395            self.console_log(output)
396        vm.console_socket.setblocking(1)
397
398    def console_send(self, command):
399        vm = self._guest
400        if self.debug:
401            logline = re.sub("\n", "<enter>", command)
402            logline = re.sub("[\x00-\x1f]", ".", logline)
403            sys.stderr.write("con send: %s\n" % logline)
404        for char in list(command):
405            vm.console_socket.send(char.encode("utf-8"))
406            time.sleep(0.01)
407
408    def console_wait_send(self, wait, command):
409        self.console_wait(wait)
410        self.console_send(command)
411
412    def console_ssh_init(self, prompt, user, pw):
413        sshkey_cmd = "echo '%s' > .ssh/authorized_keys\n" \
414                     % self._config['ssh_pub_key'].rstrip()
415        self.console_wait_send("login:",    "%s\n" % user)
416        self.console_wait_send("Password:", "%s\n" % pw)
417        self.console_wait_send(prompt,      "mkdir .ssh\n")
418        self.console_wait_send(prompt,      sshkey_cmd)
419        self.console_wait_send(prompt,      "chmod 755 .ssh\n")
420        self.console_wait_send(prompt,      "chmod 644 .ssh/authorized_keys\n")
421
422    def console_sshd_config(self, prompt):
423        self.console_wait(prompt)
424        self.console_send("echo 'PermitRootLogin yes' >> /etc/ssh/sshd_config\n")
425        for var in self.envvars:
426            self.console_wait(prompt)
427            self.console_send("echo 'AcceptEnv %s' >> /etc/ssh/sshd_config\n" % var)
428
429    def print_step(self, text):
430        sys.stderr.write("### %s ...\n" % text)
431
432    def wait_ssh(self, wait_root=False, seconds=300, cmd="exit 0"):
433        # Allow more time for VM to boot under TCG.
434        if not kvm_available(self.arch):
435            seconds *= self.tcg_timeout_multiplier
436        starttime = datetime.datetime.now()
437        endtime = starttime + datetime.timedelta(seconds=seconds)
438        cmd_success = False
439        while datetime.datetime.now() < endtime:
440            if wait_root and self.ssh_root(cmd) == 0:
441                cmd_success = True
442                break
443            elif self.ssh(cmd) == 0:
444                cmd_success = True
445                break
446            seconds = (endtime - datetime.datetime.now()).total_seconds()
447            logging.debug("%ds before timeout", seconds)
448            time.sleep(1)
449        if not cmd_success:
450            raise Exception("Timeout while waiting for guest ssh")
451
452    def shutdown(self):
453        self._guest.shutdown(timeout=self._shutdown_timeout)
454
455    def wait(self):
456        self._guest.wait(timeout=self._shutdown_timeout)
457
458    def graceful_shutdown(self):
459        self.ssh_root(self.poweroff)
460        self._guest.wait(timeout=self._shutdown_timeout)
461
462    def qmp(self, *args, **kwargs):
463        return self._guest.qmp(*args, **kwargs)
464
465    def gen_cloud_init_iso(self):
466        cidir = self._tmpdir
467        mdata = open(os.path.join(cidir, "meta-data"), "w")
468        name = self.name.replace(".","-")
469        mdata.writelines(["instance-id: {}-vm-0\n".format(name),
470                          "local-hostname: {}-guest\n".format(name)])
471        mdata.close()
472        udata = open(os.path.join(cidir, "user-data"), "w")
473        print("guest user:pw {}:{}".format(self._config['guest_user'],
474                                           self._config['guest_pass']))
475        udata.writelines(["#cloud-config\n",
476                          "chpasswd:\n",
477                          "  list: |\n",
478                          "    root:%s\n" % self._config['root_pass'],
479                          "    %s:%s\n" % (self._config['guest_user'],
480                                           self._config['guest_pass']),
481                          "  expire: False\n",
482                          "users:\n",
483                          "  - name: %s\n" % self._config['guest_user'],
484                          "    sudo: ALL=(ALL) NOPASSWD:ALL\n",
485                          "    ssh-authorized-keys:\n",
486                          "    - %s\n" % self._config['ssh_pub_key'],
487                          "  - name: root\n",
488                          "    ssh-authorized-keys:\n",
489                          "    - %s\n" % self._config['ssh_pub_key'],
490                          "locale: en_US.UTF-8\n"])
491        proxy = os.environ.get("http_proxy")
492        if not proxy is None:
493            udata.writelines(["apt:\n",
494                              "  proxy: %s" % proxy])
495        udata.close()
496        subprocess.check_call([self._genisoimage, "-output", "cloud-init.iso",
497                               "-volid", "cidata", "-joliet", "-rock",
498                               "user-data", "meta-data"],
499                              cwd=cidir,
500                              stdin=self._devnull, stdout=self._stdout,
501                              stderr=self._stdout)
502        return os.path.join(cidir, "cloud-init.iso")
503
504def get_qemu_path(arch, build_path=None):
505    """Fetch the path to the qemu binary."""
506    # If QEMU environment variable set, it takes precedence
507    if "QEMU" in os.environ:
508        qemu_path = os.environ["QEMU"]
509    elif build_path:
510        qemu_path = os.path.join(build_path, arch + "-softmmu")
511        qemu_path = os.path.join(qemu_path, "qemu-system-" + arch)
512    else:
513        # Default is to use system path for qemu.
514        qemu_path = "qemu-system-" + arch
515    return qemu_path
516
517def get_qemu_version(qemu_path):
518    """Get the version number from the current QEMU,
519       and return the major number."""
520    output = subprocess.check_output([qemu_path, '--version'])
521    version_line = output.decode("utf-8")
522    version_num = re.split(' |\(', version_line)[3].split('.')[0]
523    return int(version_num)
524
525def parse_config(config, args):
526    """ Parse yaml config and populate our config structure.
527        The yaml config allows the user to override the
528        defaults for VM parameters.  In many cases these
529        defaults can be overridden without rebuilding the VM."""
530    if args.config:
531        config_file = args.config
532    elif 'QEMU_CONFIG' in os.environ:
533        config_file = os.environ['QEMU_CONFIG']
534    else:
535        return config
536    if not os.path.exists(config_file):
537        raise Exception("config file {} does not exist".format(config_file))
538    # We gracefully handle importing the yaml module
539    # since it might not be installed.
540    # If we are here it means the user supplied a .yml file,
541    # so if the yaml module is not installed we will exit with error.
542    try:
543        import yaml
544    except ImportError:
545        print("The python3-yaml package is needed "\
546              "to support config.yaml files")
547        # Instead of raising an exception we exit to avoid
548        # a raft of messy (expected) errors to stdout.
549        exit(1)
550    with open(config_file) as f:
551        yaml_dict = yaml.safe_load(f)
552
553    if 'qemu-conf' in yaml_dict:
554        config.update(yaml_dict['qemu-conf'])
555    else:
556        raise Exception("config file {} is not valid"\
557                        " missing qemu-conf".format(config_file))
558    return config
559
560def parse_args(vmcls):
561
562    def get_default_jobs():
563        if multiprocessing.cpu_count() > 1:
564            if kvm_available(vmcls.arch):
565                return multiprocessing.cpu_count() // 2
566            elif os.uname().machine == "x86_64" and \
567                 vmcls.arch in ["aarch64", "x86_64", "i386"]:
568                # MTTCG is available on these arches and we can allow
569                # more cores. but only up to a reasonable limit. User
570                # can always override these limits with --jobs.
571                return min(multiprocessing.cpu_count() // 2, 8)
572        else:
573            return 1
574
575    parser = argparse.ArgumentParser(
576        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
577        description="Utility for provisioning VMs and running builds",
578        epilog="""Remaining arguments are passed to the command.
579        Exit codes: 0 = success, 1 = command line error,
580        2 = environment initialization failed,
581        3 = test command failed""")
582    parser.add_argument("--debug", "-D", action="store_true",
583                        help="enable debug output")
584    parser.add_argument("--image", "-i", default="%s.img" % vmcls.name,
585                        help="image file name")
586    parser.add_argument("--force", "-f", action="store_true",
587                        help="force build image even if image exists")
588    parser.add_argument("--jobs", type=int, default=get_default_jobs(),
589                        help="number of virtual CPUs")
590    parser.add_argument("--verbose", "-V", action="store_true",
591                        help="Pass V=1 to builds within the guest")
592    parser.add_argument("--build-image", "-b", action="store_true",
593                        help="build image")
594    parser.add_argument("--build-qemu",
595                        help="build QEMU from source in guest")
596    parser.add_argument("--build-target",
597                        help="QEMU build target", default="check")
598    parser.add_argument("--build-path", default=None,
599                        help="Path of build directory, "\
600                        "for using build tree QEMU binary. ")
601    parser.add_argument("--source-path", default=None,
602                        help="Path of source directory, "\
603                        "for finding additional files. ")
604    parser.add_argument("--interactive", "-I", action="store_true",
605                        help="Interactively run command")
606    parser.add_argument("--snapshot", "-s", action="store_true",
607                        help="run tests with a snapshot")
608    parser.add_argument("--genisoimage", default="genisoimage",
609                        help="iso imaging tool")
610    parser.add_argument("--config", "-c", default=None,
611                        help="Provide config yaml for configuration. "\
612                        "See config_example.yaml for example.")
613    parser.add_argument("--efi-aarch64",
614                        default="/usr/share/qemu-efi-aarch64/QEMU_EFI.fd",
615                        help="Path to efi image for aarch64 VMs.")
616    parser.add_argument("--log-console", action="store_true",
617                        help="Log console to file.")
618    parser.add_argument("commands", nargs="*", help="""Remaining
619        commands after -- are passed to command inside the VM""")
620
621    return parser.parse_args()
622
623def main(vmcls, config=None):
624    try:
625        if config == None:
626            config = DEFAULT_CONFIG
627        args = parse_args(vmcls)
628        if not args.commands and not args.build_qemu and not args.build_image:
629            print("Nothing to do?")
630            return 1
631        config = parse_config(config, args)
632        logging.basicConfig(level=(logging.DEBUG if args.debug
633                                   else logging.WARN))
634        vm = vmcls(args, config=config)
635        if args.build_image:
636            if os.path.exists(args.image) and not args.force:
637                sys.stderr.writelines(["Image file exists: %s\n" % args.image,
638                                      "Use --force option to overwrite\n"])
639                return 1
640            return vm.build_image(args.image)
641        if args.build_qemu:
642            vm.add_source_dir(args.build_qemu)
643            cmd = [vm.BUILD_SCRIPT.format(
644                   configure_opts = " ".join(args.commands),
645                   jobs=int(args.jobs),
646                   target=args.build_target,
647                   verbose = "V=1" if args.verbose else "")]
648        else:
649            cmd = args.commands
650        img = args.image
651        if args.snapshot:
652            img += ",snapshot=on"
653        vm.boot(img)
654        vm.wait_ssh()
655    except Exception as e:
656        if isinstance(e, SystemExit) and e.code == 0:
657            return 0
658        sys.stderr.write("Failed to prepare guest environment\n")
659        traceback.print_exc()
660        return 2
661
662    exitcode = 0
663    if vm.ssh(*cmd) != 0:
664        exitcode = 3
665    if args.interactive:
666        vm.ssh()
667
668    if not args.snapshot:
669        vm.graceful_shutdown()
670
671    return exitcode
672