scripts/qmp/qom-fuse

   1 #!/usr/bin/env python3
   2 ##
   3 # QEMU Object Model test tools
   4 #
   5 # Copyright IBM, Corp. 2012
   6 # Copyright (C) 2020 Red Hat, Inc.
   7 #
   8 # Authors:
   9 #  Anthony Liguori   <aliguori@us.ibm.com>
  10 #  Markus Armbruster <armbru@redhat.com>
  11 #
  12 # This work is licensed under the terms of the GNU GPL, version 2 or later.  See
  13 # the COPYING file in the top-level directory.
  14 ##
  15
  16 import fuse, stat
  17 from fuse import FUSE, FuseOSError, Operations
  18 import os, posix, sys
  19 from errno import *
  20
  21 sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..', 'python'))
  22 from qemu.qmp import QEMUMonitorProtocol
  23
  24 fuse.fuse_python_api = (0, 2)
  25
  26 class QOMFS(Operations):
  27     def __init__(self, qmp):
  28         self.qmp = qmp
  29         self.qmp.connect()
  30         self.ino_map = {}
  31         self.ino_count = 1
  32
  33     def get_ino(self, path):
  34         if path in self.ino_map:
  35             return self.ino_map[path]
  36         self.ino_map[path] = self.ino_count
  37         self.ino_count += 1
  38         return self.ino_map[path]
  39
  40     def is_object(self, path):
  41         try:
  42             items = self.qmp.command('qom-list', path=path)
  43             return True
  44         except:
  45             return False
  46
  47     def is_property(self, path):
  48         path, prop = path.rsplit('/', 1)
  49         if path == '':
  50             path = '/'
  51         try:
  52             for item in self.qmp.command('qom-list', path=path):
  53                 if item['name'] == prop:
  54                     return True
  55             return False
  56         except:
  57             return False
  58
  59     def is_link(self, path):
  60         path, prop = path.rsplit('/', 1)
  61         if path == '':
  62             path = '/'
  63         try:
  64             for item in self.qmp.command('qom-list', path=path):
  65                 if item['name'] == prop:
  66                     if item['type'].startswith('link<'):
  67                         return True
  68                     return False
  69             return False
  70         except:
  71             return False
  72
  73     def read(self, path, length, offset, fh):
  74         if not self.is_property(path):
  75             return -ENOENT
  76
  77         path, prop = path.rsplit('/', 1)
  78         if path == '':
  79             path = '/'
  80         try:
  81             data = self.qmp.command('qom-get', path=path, property=prop)
  82             data += '\n' # make values shell friendly
  83         except:
  84             raise FuseOSError(EPERM)
  85
  86         if offset > len(data):
  87             return ''
  88
  89         return bytes(data[offset:][:length], encoding='utf-8')
  90
  91     def readlink(self, path):
  92         if not self.is_link(path):
  93             return False
  94         path, prop = path.rsplit('/', 1)
  95         prefix = '/'.join(['..'] * (len(path.split('/')) - 1))
  96         return prefix + str(self.qmp.command('qom-get', path=path,
  97                                              property=prop))
  98
  99     def getattr(self, path, fh=None):
 100         if self.is_link(path):
 101             value = { 'st_mode': 0o755 | stat.S_IFLNK,
 102                       'st_ino': self.get_ino(path),
 103                       'st_dev': 0,
 104                       'st_nlink': 2,
 105                       'st_uid': 1000,
 106                       'st_gid': 1000,
 107                       'st_size': 4096,
 108                       'st_atime': 0,
 109                       'st_mtime': 0,
 110                       'st_ctime': 0 }
 111         elif self.is_object(path):
 112             value = { 'st_mode': 0o755 | stat.S_IFDIR,
 113                       'st_ino': self.get_ino(path),
 114                       'st_dev': 0,
 115                       'st_nlink': 2,
 116                       'st_uid': 1000,
 117                       'st_gid': 1000,
 118                       'st_size': 4096,
 119                       'st_atime': 0,
 120                       'st_mtime': 0,
 121                       'st_ctime': 0 }
 122         elif self.is_property(path):
 123             value = { 'st_mode': 0o644 | stat.S_IFREG,
 124                       'st_ino': self.get_ino(path),
 125                       'st_dev': 0,
 126                       'st_nlink': 1,
 127                       'st_uid': 1000,
 128                       'st_gid': 1000,
 129                       'st_size': 4096,
 130                       'st_atime': 0,
 131                       'st_mtime': 0,
 132                       'st_ctime': 0 }
 133         else:
 134             raise FuseOSError(ENOENT)
 135         return value
 136
 137     def readdir(self, path, fh):
 138         yield '.'
 139         yield '..'
 140         for item in self.qmp.command('qom-list', path=path):
 141             yield str(item['name'])
 142
 143 if __name__ == '__main__':
 144     import os
 145
 146     fuse = FUSE(QOMFS(QEMUMonitorProtocol(os.environ['QMP_SOCKET'])),
 147                 sys.argv[1], foreground=True)