scripts/qemu.py

   1 # QEMU library
   2 #
   3 # Copyright (C) 2015-2016 Red Hat Inc.
   4 # Copyright (C) 2012 IBM Corp.
   5 #
   6 # Authors:
   7 #  Fam Zheng <famz@redhat.com>
   8 #
   9 # This work is licensed under the terms of the GNU GPL, version 2.  See
  10 # the COPYING file in the top-level directory.
  11 #
  12 # Based on qmp.py.
  13 #
  14
  15 import errno
  16 import string
  17 import os
  18 import sys
  19 import subprocess
  20 import qmp.qmp
  21
  22
  23 class QEMUMachine(object):
  24     '''A QEMU VM'''
  25
  26     def __init__(self, binary, args=[], wrapper=[], name=None, test_dir="/var/tmp",
  27                  monitor_address=None, socket_scm_helper=None, debug=False):
  28         if name is None:
  29             name = "qemu-%d" % os.getpid()
  30         if monitor_address is None:
  31             monitor_address = os.path.join(test_dir, name + "-monitor.sock")
  32         self._monitor_address = monitor_address
  33         self._qemu_log_path = os.path.join(test_dir, name + ".log")
  34         self._popen = None
  35         self._binary = binary
  36         self._args = list(args) # Force copy args in case we modify them
  37         self._wrapper = wrapper
  38         self._events = []
  39         self._iolog = None
  40         self._socket_scm_helper = socket_scm_helper
  41         self._debug = debug
  42
  43     # This can be used to add an unused monitor instance.
  44     def add_monitor_telnet(self, ip, port):
  45         args = 'tcp:%s:%d,server,nowait,telnet' % (ip, port)
  46         self._args.append('-monitor')
  47         self._args.append(args)
  48
  49     def add_fd(self, fd, fdset, opaque, opts=''):
  50         '''Pass a file descriptor to the VM'''
  51         options = ['fd=%d' % fd,
  52                    'set=%d' % fdset,
  53                    'opaque=%s' % opaque]
  54         if opts:
  55             options.append(opts)
  56
  57         self._args.append('-add-fd')
  58         self._args.append(','.join(options))
  59         return self
  60
  61     def send_fd_scm(self, fd_file_path):
  62         # In iotest.py, the qmp should always use unix socket.
  63         assert self._qmp.is_scm_available()
  64         if self._socket_scm_helper is None:
  65             print >>sys.stderr, "No path to socket_scm_helper set"
  66             return -1
  67         if os.path.exists(self._socket_scm_helper) == False:
  68             print >>sys.stderr, "%s does not exist" % self._socket_scm_helper
  69             return -1
  70         fd_param = ["%s" % self._socket_scm_helper,
  71                     "%d" % self._qmp.get_sock_fd(),
  72                     "%s" % fd_file_path]
  73         devnull = open('/dev/null', 'rb')
  74         p = subprocess.Popen(fd_param, stdin=devnull, stdout=sys.stdout,
  75                              stderr=sys.stderr)
  76         return p.wait()
  77
  78     @staticmethod
  79     def _remove_if_exists(path):
  80         '''Remove file object at path if it exists'''
  81         try:
  82             os.remove(path)
  83         except OSError as exception:
  84             if exception.errno == errno.ENOENT:
  85                 return
  86             raise
  87
  88     def get_pid(self):
  89         if not self._popen:
  90             return None
  91         return self._popen.pid
  92
  93     def _load_io_log(self):
  94         with open(self._qemu_log_path, "r") as fh:
  95             self._iolog = fh.read()
  96
  97     def _base_args(self):
  98         if isinstance(self._monitor_address, tuple):
  99             moncdev = "socket,id=mon,host=%s,port=%s" % (
 100                 self._monitor_address[0],
 101                 self._monitor_address[1])
 102         else:
 103             moncdev = 'socket,id=mon,path=%s' % self._monitor_address
 104         return ['-chardev', moncdev,
 105                 '-mon', 'chardev=mon,mode=control',
 106                 '-display', 'none', '-vga', 'none']
 107
 108     def _pre_launch(self):
 109         self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address, server=True,
 110                                                 debug=self._debug)
 111
 112     def _post_launch(self):
 113         self._qmp.accept()
 114
 115     def _post_shutdown(self):
 116         if not isinstance(self._monitor_address, tuple):
 117             self._remove_if_exists(self._monitor_address)
 118         self._remove_if_exists(self._qemu_log_path)
 119
 120     def launch(self):
 121         '''Launch the VM and establish a QMP connection'''
 122         devnull = open('/dev/null', 'rb')
 123         qemulog = open(self._qemu_log_path, 'wb')
 124         try:
 125             self._pre_launch()
 126             args = self._wrapper + [self._binary] + self._base_args() + self._args
 127             self._popen = subprocess.Popen(args, stdin=devnull, stdout=qemulog,
 128                                            stderr=subprocess.STDOUT, shell=False)
 129             self._post_launch()
 130         except:
 131             if self._popen:
 132                 self._popen.kill()
 133             self._load_io_log()
 134             self._post_shutdown()
 135             self._popen = None
 136             raise
 137
 138     def shutdown(self):
 139         '''Terminate the VM and clean up'''
 140         if not self._popen is None:
 141             try:
 142                 self._qmp.cmd('quit')
 143                 self._qmp.close()
 144             except:
 145                 self._popen.kill()
 146
 147             exitcode = self._popen.wait()
 148             if exitcode < 0:
 149                 sys.stderr.write('qemu received signal %i: %s\n' % (-exitcode, ' '.join(self._args)))
 150             self._load_io_log()
 151             self._post_shutdown()
 152             self._popen = None
 153
 154     underscore_to_dash = string.maketrans('_', '-')
 155     def qmp(self, cmd, conv_keys=True, **args):
 156         '''Invoke a QMP command and return the result dict'''
 157         qmp_args = dict()
 158         for k in args.keys():
 159             if conv_keys:
 160                 qmp_args[k.translate(self.underscore_to_dash)] = args[k]
 161             else:
 162                 qmp_args[k] = args[k]
 163
 164         return self._qmp.cmd(cmd, args=qmp_args)
 165
 166     def command(self, cmd, conv_keys=True, **args):
 167         reply = self.qmp(cmd, conv_keys, **args)
 168         if reply is None:
 169             raise Exception("Monitor is closed")
 170         if "error" in reply:
 171             raise Exception(reply["error"]["desc"])
 172         return reply["return"]
 173
 174     def get_qmp_event(self, wait=False):
 175         '''Poll for one queued QMP events and return it'''
 176         if len(self._events) > 0:
 177             return self._events.pop(0)
 178         return self._qmp.pull_event(wait=wait)
 179
 180     def get_qmp_events(self, wait=False):
 181         '''Poll for queued QMP events and return a list of dicts'''
 182         events = self._qmp.get_events(wait=wait)
 183         events.extend(self._events)
 184         del self._events[:]
 185         self._qmp.clear_events()
 186         return events
 187
 188     def event_wait(self, name, timeout=60.0, match=None):
 189         # Test if 'match' is a recursive subset of 'event'
 190         def event_match(event, match=None):
 191             if match is None:
 192                 return True
 193
 194             for key in match:
 195                 if key in event:
 196                     if isinstance(event[key], dict):
 197                         if not event_match(event[key], match[key]):
 198                             return False
 199                     elif event[key] != match[key]:
 200                         return False
 201                 else:
 202                     return False
 203
 204             return True
 205
 206         # Search cached events
 207         for event in self._events:
 208             if (event['event'] == name) and event_match(event, match):
 209                 self._events.remove(event)
 210                 return event
 211
 212         # Poll for new events
 213         while True:
 214             event = self._qmp.pull_event(wait=timeout)
 215             if (event['event'] == name) and event_match(event, match):
 216                 return event
 217             self._events.append(event)
 218
 219         return None
 220
 221     def get_log(self):
 222         return self._iolog