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-rw-r--r--python/qemu/qmp/qom_fuse.py206
1 files changed, 206 insertions, 0 deletions
diff --git a/python/qemu/qmp/qom_fuse.py b/python/qemu/qmp/qom_fuse.py
new file mode 100644
index 0000000000..43f4671fdb
--- /dev/null
+++ b/python/qemu/qmp/qom_fuse.py
@@ -0,0 +1,206 @@
+"""
+QEMU Object Model FUSE filesystem tool
+
+This script offers a simple FUSE filesystem within which the QOM tree
+may be browsed, queried and edited using traditional shell tooling.
+
+This script requires the 'fusepy' python package.
+
+
+usage: qom-fuse [-h] [--socket SOCKET] <mount>
+
+Mount a QOM tree as a FUSE filesystem
+
+positional arguments:
+ <mount> Mount point
+
+optional arguments:
+ -h, --help show this help message and exit
+ --socket SOCKET, -s SOCKET
+ QMP socket path or address (addr:port). May also be
+ set via QMP_SOCKET environment variable.
+"""
+##
+# Copyright IBM, Corp. 2012
+# Copyright (C) 2020 Red Hat, Inc.
+#
+# Authors:
+# Anthony Liguori <aliguori@us.ibm.com>
+# Markus Armbruster <armbru@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2 or later.
+# See the COPYING file in the top-level directory.
+##
+
+import argparse
+from errno import ENOENT, EPERM
+import stat
+import sys
+from typing import (
+ IO,
+ Dict,
+ Iterator,
+ Mapping,
+ Optional,
+ Union,
+)
+
+import fuse
+from fuse import FUSE, FuseOSError, Operations
+
+from . import QMPResponseError
+from .qom_common import QOMCommand
+
+
+fuse.fuse_python_api = (0, 2)
+
+
+class QOMFuse(QOMCommand, Operations):
+ """
+ QOMFuse implements both fuse.Operations and QOMCommand.
+
+ Operations implements the FS, and QOMCommand implements the CLI command.
+ """
+ name = 'fuse'
+ help = 'Mount a QOM tree as a FUSE filesystem'
+ fuse: FUSE
+
+ @classmethod
+ def configure_parser(cls, parser: argparse.ArgumentParser) -> None:
+ super().configure_parser(parser)
+ parser.add_argument(
+ 'mount',
+ metavar='<mount>',
+ action='store',
+ help="Mount point",
+ )
+
+ def __init__(self, args: argparse.Namespace):
+ super().__init__(args)
+ self.mount = args.mount
+ self.ino_map: Dict[str, int] = {}
+ self.ino_count = 1
+
+ def run(self) -> int:
+ print(f"Mounting QOMFS to '{self.mount}'", file=sys.stderr)
+ self.fuse = FUSE(self, self.mount, foreground=True)
+ return 0
+
+ def get_ino(self, path: str) -> int:
+ """Get an inode number for a given QOM path."""
+ if path in self.ino_map:
+ return self.ino_map[path]
+ self.ino_map[path] = self.ino_count
+ self.ino_count += 1
+ return self.ino_map[path]
+
+ def is_object(self, path: str) -> bool:
+ """Is the given QOM path an object?"""
+ try:
+ self.qom_list(path)
+ return True
+ except QMPResponseError:
+ return False
+
+ def is_property(self, path: str) -> bool:
+ """Is the given QOM path a property?"""
+ path, prop = path.rsplit('/', 1)
+ if path == '':
+ path = '/'
+ try:
+ for item in self.qom_list(path):
+ if item.name == prop:
+ return True
+ return False
+ except QMPResponseError:
+ return False
+
+ def is_link(self, path: str) -> bool:
+ """Is the given QOM path a link?"""
+ path, prop = path.rsplit('/', 1)
+ if path == '':
+ path = '/'
+ try:
+ for item in self.qom_list(path):
+ if item.name == prop and item.link:
+ return True
+ return False
+ except QMPResponseError:
+ return False
+
+ def read(self, path: str, size: int, offset: int, fh: IO[bytes]) -> bytes:
+ if not self.is_property(path):
+ raise FuseOSError(ENOENT)
+
+ path, prop = path.rsplit('/', 1)
+ if path == '':
+ path = '/'
+ try:
+ data = str(self.qmp.command('qom-get', path=path, property=prop))
+ data += '\n' # make values shell friendly
+ except QMPResponseError as err:
+ raise FuseOSError(EPERM) from err
+
+ if offset > len(data):
+ return b''
+
+ return bytes(data[offset:][:size], encoding='utf-8')
+
+ def readlink(self, path: str) -> Union[bool, str]:
+ if not self.is_link(path):
+ return False
+ path, prop = path.rsplit('/', 1)
+ prefix = '/'.join(['..'] * (len(path.split('/')) - 1))
+ return prefix + str(self.qmp.command('qom-get', path=path,
+ property=prop))
+
+ def getattr(self, path: str,
+ fh: Optional[IO[bytes]] = None) -> Mapping[str, object]:
+ if self.is_link(path):
+ value = {
+ 'st_mode': 0o755 | stat.S_IFLNK,
+ 'st_ino': self.get_ino(path),
+ 'st_dev': 0,
+ 'st_nlink': 2,
+ 'st_uid': 1000,
+ 'st_gid': 1000,
+ 'st_size': 4096,
+ 'st_atime': 0,
+ 'st_mtime': 0,
+ 'st_ctime': 0
+ }
+ elif self.is_object(path):
+ value = {
+ 'st_mode': 0o755 | stat.S_IFDIR,
+ 'st_ino': self.get_ino(path),
+ 'st_dev': 0,
+ 'st_nlink': 2,
+ 'st_uid': 1000,
+ 'st_gid': 1000,
+ 'st_size': 4096,
+ 'st_atime': 0,
+ 'st_mtime': 0,
+ 'st_ctime': 0
+ }
+ elif self.is_property(path):
+ value = {
+ 'st_mode': 0o644 | stat.S_IFREG,
+ 'st_ino': self.get_ino(path),
+ 'st_dev': 0,
+ 'st_nlink': 1,
+ 'st_uid': 1000,
+ 'st_gid': 1000,
+ 'st_size': 4096,
+ 'st_atime': 0,
+ 'st_mtime': 0,
+ 'st_ctime': 0
+ }
+ else:
+ raise FuseOSError(ENOENT)
+ return value
+
+ def readdir(self, path: str, fh: IO[bytes]) -> Iterator[str]:
+ yield '.'
+ yield '..'
+ for item in self.qom_list(path):
+ yield item.name