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authorPeter Maydell <peter.maydell@linaro.org>2022-01-22 12:03:22 +0000
committerPeter Maydell <peter.maydell@linaro.org>2022-01-22 12:03:22 +0000
commitaeb0ae95b7f18c66158792641cb6ba0cde5789ab (patch)
tree295ec2800a9340195c95f52c94520aa479f89ce0 /python/qemu/utils/qom_fuse.py
parent5e9d14f2bea6df89c0675df953f9c839560d2266 (diff)
parent05908602429cf9d6fce9b60704b8395f6d295441 (diff)
downloadfocaccia-qemu-aeb0ae95b7f18c66158792641cb6ba0cde5789ab.tar.gz
focaccia-qemu-aeb0ae95b7f18c66158792641cb6ba0cde5789ab.zip
Merge remote-tracking branch 'remotes/jsnow-gitlab/tags/python-pull-request' into staging
Python patches

A few fixes to the Python CI tests, a few fixes to the (async) QMP
library, and a set of patches that begin to shift us towards using the
new qmp lib.

# gpg: Signature made Sat 22 Jan 2022 00:07:58 GMT
# gpg:                using RSA key F9B7ABDBBCACDF95BE76CBD07DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>" [full]
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jsnow-gitlab/tags/python-pull-request:
  scripts/render-block-graph: switch to AQMP
  scripts/cpu-x86-uarch-abi: switch to AQMP
  scripts/cpu-x86-uarch-abi: fix CLI parsing
  python: move qmp-shell under the AQMP package
  python: move qmp utilities to python/qemu/utils
  python/qmp: switch qmp-shell to AQMP
  python/qmp: switch qom tools to AQMP
  python/qmp: switch qemu-ga-client to AQMP
  python/qemu-ga-client: don't use deprecated CLI syntax in usage comment
  python/aqmp: rename AQMPError to QMPError
  python/aqmp: add SocketAddrT to package root
  python/aqmp: copy type definitions from qmp
  python/aqmp: handle asyncio.TimeoutError on execute()
  python/aqmp: add __del__ method to legacy interface
  python/aqmp: fix docstring typo
  python: use avocado's "new" runner
  python: pin setuptools below v60.0.0

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'python/qemu/utils/qom_fuse.py')
-rw-r--r--python/qemu/utils/qom_fuse.py207
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diff --git a/python/qemu/utils/qom_fuse.py b/python/qemu/utils/qom_fuse.py
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+++ b/python/qemu/utils/qom_fuse.py
@@ -0,0 +1,207 @@
+"""
+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 qemu.aqmp import ExecuteError
+
+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 ExecuteError:
+            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 ExecuteError:
+            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 ExecuteError:
+            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 ExecuteError 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