scripts/qmp-shell: move to python/qemu/qmp/qmp_shell.py

The script will be unavailable for a commit or two, which will help
preserve development history attached to the new file. A forwarder will
be added shortly afterwards.

With qmp_shell in the python qemu.qmp package, now it is fully type
checked, linted, etc. via the Python CI. It will be quite a bit harder
to accidentally break it again in the future.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210607200649.1840382-41-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>

1 files changed, 0 insertions, 538 deletions

diff --git a/scripts/qmp/qmp-shell b/scripts/qmp/qmp-shell
deleted file mode 100755
index 15aedb80c2..0000000000
--- a/scripts/qmp/qmp-shell
+++ /dev/null
@@ -1,538 +0,0 @@
-#!/usr/bin/env python3
-#
-# Copyright (C) 2009, 2010 Red Hat Inc.
-#
-# Authors:
-#  Luiz Capitulino <lcapitulino@redhat.com>
-#
-# This work is licensed under the terms of the GNU GPL, version 2.  See
-# the COPYING file in the top-level directory.
-#
-
-"""
-Low-level QEMU shell on top of QMP.
-
-usage: qmp-shell [-h] [-H] [-N] [-v] [-p] qmp_server
-
-positional arguments:
-  qmp_server            < UNIX socket path | TCP address:port >
-
-optional arguments:
-  -h, --help            show this help message and exit
-  -H, --hmp             Use HMP interface
-  -N, --skip-negotiation
-                        Skip negotiate (for qemu-ga)
-  -v, --verbose         Verbose (echo commands sent and received)
-  -p, --pretty          Pretty-print JSON
-
-
-Start QEMU with:
-
-# qemu [...] -qmp unix:./qmp-sock,server
-
-Run the shell:
-
-$ qmp-shell ./qmp-sock
-
-Commands have the following format:
-
-   < command-name > [ arg-name1=arg1 ] ... [ arg-nameN=argN ]
-
-For example:
-
-(QEMU) device_add driver=e1000 id=net1
-{'return': {}}
-(QEMU)
-
-key=value pairs also support Python or JSON object literal subset notations,
-without spaces. Dictionaries/objects {} are supported as are arrays [].
-
-   example-command arg-name1={'key':'value','obj'={'prop':"value"}}
-
-Both JSON and Python formatting should work, including both styles of
-string literal quotes. Both paradigms of literal values should work,
-including null/true/false for JSON and None/True/False for Python.
-
-
-Transactions have the following multi-line format:
-
-   transaction(
-   action-name1 [ arg-name1=arg1 ] ... [arg-nameN=argN ]
-   ...
-   action-nameN [ arg-name1=arg1 ] ... [arg-nameN=argN ]
-   )
-
-One line transactions are also supported:
-
-   transaction( action-name1 ... )
-
-For example:
-
-    (QEMU) transaction(
-    TRANS> block-dirty-bitmap-add node=drive0 name=bitmap1
-    TRANS> block-dirty-bitmap-clear node=drive0 name=bitmap0
-    TRANS> )
-    {"return": {}}
-    (QEMU)
-
-Use the -v and -p options to activate the verbose and pretty-print options,
-which will echo back the properly formatted JSON-compliant QMP that is being
-sent to QEMU, which is useful for debugging and documentation generation.
-"""
-
-import argparse
-import ast
-import json
-import logging
-import os
-import re
-import readline
-import sys
-from typing import (
-    Iterator,
-    List,
-    NoReturn,
-    Optional,
-    Sequence,
-)
-
-
-sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..', 'python'))
-from qemu import qmp
-from qemu.qmp import QMPMessage
-
-
-LOG = logging.getLogger(__name__)
-
-
-class QMPCompleter:
-    """
-    QMPCompleter provides a readline library tab-complete behavior.
-    """
-    # NB: Python 3.9+ will probably allow us to subclass list[str] directly,
-    # but pylint as of today does not know that List[str] is simply 'list'.
-    def __init__(self) -> None:
-        self._matches: List[str] = []
-
-    def append(self, value: str) -> None:
-        """Append a new valid completion to the list of possibilities."""
-        return self._matches.append(value)
-
-    def complete(self, text: str, state: int) -> Optional[str]:
-        """readline.set_completer() callback implementation."""
-        for cmd in self._matches:
-            if cmd.startswith(text):
-                if state == 0:
-                    return cmd
-                state -= 1
-        return None
-
-
-class QMPShellError(qmp.QMPError):
-    """
-    QMP Shell Base error class.
-    """
-
-
-class FuzzyJSON(ast.NodeTransformer):
-    """
-    This extension of ast.NodeTransformer filters literal "true/false/null"
-    values in a Python AST and replaces them by proper "True/False/None" values
-    that Python can properly evaluate.
-    """
-
-    @classmethod
-    def visit_Name(cls,  # pylint: disable=invalid-name
-                   node: ast.Name) -> ast.AST:
-        """
-        Transform Name nodes with certain values into Constant (keyword) nodes.
-        """
-        if node.id == 'true':
-            return ast.Constant(value=True)
-        if node.id == 'false':
-            return ast.Constant(value=False)
-        if node.id == 'null':
-            return ast.Constant(value=None)
-        return node
-
-
-class QMPShell(qmp.QEMUMonitorProtocol):
-    """
-    QMPShell provides a basic readline-based QMP shell.
-
-    :param address: Address of the QMP server.
-    :param pretty: Pretty-print QMP messages.
-    :param verbose: Echo outgoing QMP messages to console.
-    """
-    def __init__(self, address: qmp.SocketAddrT,
-                 pretty: bool = False, verbose: bool = False):
-        super().__init__(address)
-        self._greeting: Optional[QMPMessage] = None
-        self._completer = QMPCompleter()
-        self._transmode = False
-        self._actions: List[QMPMessage] = []
-        self._histfile = os.path.join(os.path.expanduser('~'),
-                                      '.qmp-shell_history')
-        self.pretty = pretty
-        self.verbose = verbose
-
-    def close(self) -> None:
-        # Hook into context manager of parent to save shell history.
-        self._save_history()
-        super().close()
-
-    def _fill_completion(self) -> None:
-        cmds = self.cmd('query-commands')
-        if 'error' in cmds:
-            return
-        for cmd in cmds['return']:
-            self._completer.append(cmd['name'])
-
-    def _completer_setup(self) -> None:
-        self._completer = QMPCompleter()
-        self._fill_completion()
-        readline.set_history_length(1024)
-        readline.set_completer(self._completer.complete)
-        readline.parse_and_bind("tab: complete")
-        # NB: default delimiters conflict with some command names
-        # (eg. query-), clearing everything as it doesn't seem to matter
-        readline.set_completer_delims('')
-        try:
-            readline.read_history_file(self._histfile)
-        except FileNotFoundError:
-            pass
-        except IOError as err:
-            msg = f"Failed to read history '{self._histfile}': {err!s}"
-            LOG.warning(msg)
-
-    def _save_history(self) -> None:
-        try:
-            readline.write_history_file(self._histfile)
-        except IOError as err:
-            msg = f"Failed to save history file '{self._histfile}': {err!s}"
-            LOG.warning(msg)
-
-    @classmethod
-    def _parse_value(cls, val: str) -> object:
-        try:
-            return int(val)
-        except ValueError:
-            pass
-
-        if val.lower() == 'true':
-            return True
-        if val.lower() == 'false':
-            return False
-        if val.startswith(('{', '[')):
-            # Try first as pure JSON:
-            try:
-                return json.loads(val)
-            except ValueError:
-                pass
-            # Try once again as FuzzyJSON:
-            try:
-                tree = ast.parse(val, mode='eval')
-                transformed = FuzzyJSON().visit(tree)
-                return ast.literal_eval(transformed)
-            except (SyntaxError, ValueError):
-                pass
-        return val
-
-    def _cli_expr(self,
-                  tokens: Sequence[str],
-                  parent: qmp.QMPObject) -> None:
-        for arg in tokens:
-            (key, sep, val) = arg.partition('=')
-            if sep != '=':
-                raise QMPShellError(
-                    f"Expected a key=value pair, got '{arg!s}'"
-                )
-
-            value = self._parse_value(val)
-            optpath = key.split('.')
-            curpath = []
-            for path in optpath[:-1]:
-                curpath.append(path)
-                obj = parent.get(path, {})
-                if not isinstance(obj, dict):
-                    msg = 'Cannot use "{:s}" as both leaf and non-leaf key'
-                    raise QMPShellError(msg.format('.'.join(curpath)))
-                parent[path] = obj
-                parent = obj
-            if optpath[-1] in parent:
-                if isinstance(parent[optpath[-1]], dict):
-                    msg = 'Cannot use "{:s}" as both leaf and non-leaf key'
-                    raise QMPShellError(msg.format('.'.join(curpath)))
-                raise QMPShellError(f'Cannot set "{key}" multiple times')
-            parent[optpath[-1]] = value
-
-    def _build_cmd(self, cmdline: str) -> Optional[QMPMessage]:
-        """
-        Build a QMP input object from a user provided command-line in the
-        following format:
-
-            < command-name > [ arg-name1=arg1 ] ... [ arg-nameN=argN ]
-        """
-        argument_regex = r'''(?:[^\s"']|"(?:\\.|[^"])*"|'(?:\\.|[^'])*')+'''
-        cmdargs = re.findall(argument_regex, cmdline)
-        qmpcmd: QMPMessage
-
-        # Transactional CLI entry:
-        if cmdargs and cmdargs[0] == 'transaction(':
-            self._transmode = True
-            self._actions = []
-            cmdargs.pop(0)
-
-        # Transactional CLI exit:
-        if cmdargs and cmdargs[0] == ')' and self._transmode:
-            self._transmode = False
-            if len(cmdargs) > 1:
-                msg = 'Unexpected input after close of Transaction sub-shell'
-                raise QMPShellError(msg)
-            qmpcmd = {
-                'execute': 'transaction',
-                'arguments': {'actions': self._actions}
-            }
-            return qmpcmd
-
-        # No args, or no args remaining
-        if not cmdargs:
-            return None
-
-        if self._transmode:
-            # Parse and cache this Transactional Action
-            finalize = False
-            action = {'type': cmdargs[0], 'data': {}}
-            if cmdargs[-1] == ')':
-                cmdargs.pop(-1)
-                finalize = True
-            self._cli_expr(cmdargs[1:], action['data'])
-            self._actions.append(action)
-            return self._build_cmd(')') if finalize else None
-
-        # Standard command: parse and return it to be executed.
-        qmpcmd = {'execute': cmdargs[0], 'arguments': {}}
-        self._cli_expr(cmdargs[1:], qmpcmd['arguments'])
-        return qmpcmd
-
-    def _print(self, qmp_message: object) -> None:
-        jsobj = json.dumps(qmp_message,
-                           indent=4 if self.pretty else None,
-                           sort_keys=self.pretty)
-        print(str(jsobj))
-
-    def _execute_cmd(self, cmdline: str) -> bool:
-        try:
-            qmpcmd = self._build_cmd(cmdline)
-        except QMPShellError as err:
-            print(
-                f"Error while parsing command line: {err!s}\n"
-                "command format: <command-name> "
-                "[arg-name1=arg1] ... [arg-nameN=argN",
-                file=sys.stderr
-            )
-            return True
-        # For transaction mode, we may have just cached the action:
-        if qmpcmd is None:
-            return True
-        if self.verbose:
-            self._print(qmpcmd)
-        resp = self.cmd_obj(qmpcmd)
-        if resp is None:
-            print('Disconnected')
-            return False
-        self._print(resp)
-        return True
-
-    def connect(self, negotiate: bool = True) -> None:
-        self._greeting = super().connect(negotiate)
-        self._completer_setup()
-
-    def show_banner(self,
-                    msg: str = 'Welcome to the QMP low-level shell!') -> None:
-        """
-        Print to stdio a greeting, and the QEMU version if available.
-        """
-        print(msg)
-        if not self._greeting:
-            print('Connected')
-            return
-        version = self._greeting['QMP']['version']['qemu']
-        print("Connected to QEMU {major}.{minor}.{micro}\n".format(**version))
-
-    @property
-    def prompt(self) -> str:
-        """
-        Return the current shell prompt, including a trailing space.
-        """
-        if self._transmode:
-            return 'TRANS> '
-        return '(QEMU) '
-
-    def read_exec_command(self) -> bool:
-        """
-        Read and execute a command.
-
-        @return True if execution was ok, return False if disconnected.
-        """
-        try:
-            cmdline = input(self.prompt)
-        except EOFError:
-            print()
-            return False
-
-        if cmdline == '':
-            for event in self.get_events():
-                print(event)
-            self.clear_events()
-            return True
-
-        return self._execute_cmd(cmdline)
-
-    def repl(self) -> Iterator[None]:
-        """
-        Return an iterator that implements the REPL.
-        """
-        self.show_banner()
-        while self.read_exec_command():
-            yield
-        self.close()
-
-
-class HMPShell(QMPShell):
-    """
-    HMPShell provides a basic readline-based HMP shell, tunnelled via QMP.
-
-    :param address: Address of the QMP server.
-    :param pretty: Pretty-print QMP messages.
-    :param verbose: Echo outgoing QMP messages to console.
-    """
-    def __init__(self, address: qmp.SocketAddrT,
-                 pretty: bool = False, verbose: bool = False):
-        super().__init__(address, pretty, verbose)
-        self._cpu_index = 0
-
-    def _cmd_completion(self) -> None:
-        for cmd in self._cmd_passthrough('help')['return'].split('\r\n'):
-            if cmd and cmd[0] != '[' and cmd[0] != '\t':
-                name = cmd.split()[0]  # drop help text
-                if name == 'info':
-                    continue
-                if name.find('|') != -1:
-                    # Command in the form 'foobar|f' or 'f|foobar', take the
-                    # full name
-                    opt = name.split('|')
-                    if len(opt[0]) == 1:
-                        name = opt[1]
-                    else:
-                        name = opt[0]
-                self._completer.append(name)
-                self._completer.append('help ' + name)  # help completion
-
-    def _info_completion(self) -> None:
-        for cmd in self._cmd_passthrough('info')['return'].split('\r\n'):
-            if cmd:
-                self._completer.append('info ' + cmd.split()[1])
-
-    def _other_completion(self) -> None:
-        # special cases
-        self._completer.append('help info')
-
-    def _fill_completion(self) -> None:
-        self._cmd_completion()
-        self._info_completion()
-        self._other_completion()
-
-    def _cmd_passthrough(self, cmdline: str,
-                         cpu_index: int = 0) -> QMPMessage:
-        return self.cmd_obj({
-            'execute': 'human-monitor-command',
-            'arguments': {
-                'command-line': cmdline,
-                'cpu-index': cpu_index
-            }
-        })
-
-    def _execute_cmd(self, cmdline: str) -> bool:
-        if cmdline.split()[0] == "cpu":
-            # trap the cpu command, it requires special setting
-            try:
-                idx = int(cmdline.split()[1])
-                if 'return' not in self._cmd_passthrough('info version', idx):
-                    print('bad CPU index')
-                    return True
-                self._cpu_index = idx
-            except ValueError:
-                print('cpu command takes an integer argument')
-                return True
-        resp = self._cmd_passthrough(cmdline, self._cpu_index)
-        if resp is None:
-            print('Disconnected')
-            return False
-        assert 'return' in resp or 'error' in resp
-        if 'return' in resp:
-            # Success
-            if len(resp['return']) > 0:
-                print(resp['return'], end=' ')
-        else:
-            # Error
-            print('%s: %s' % (resp['error']['class'], resp['error']['desc']))
-        return True
-
-    def show_banner(self, msg: str = 'Welcome to the HMP shell!') -> None:
-        QMPShell.show_banner(self, msg)
-
-
-def die(msg: str) -> NoReturn:
-    """Write an error to stderr, then exit with a return code of 1."""
-    sys.stderr.write('ERROR: %s\n' % msg)
-    sys.exit(1)
-
-
-def main() -> None:
-    """
-    qmp-shell entry point: parse command line arguments and start the REPL.
-    """
-    parser = argparse.ArgumentParser()
-    parser.add_argument('-H', '--hmp', action='store_true',
-                        help='Use HMP interface')
-    parser.add_argument('-N', '--skip-negotiation', action='store_true',
-                        help='Skip negotiate (for qemu-ga)')
-    parser.add_argument('-v', '--verbose', action='store_true',
-                        help='Verbose (echo commands sent and received)')
-    parser.add_argument('-p', '--pretty', action='store_true',
-                        help='Pretty-print JSON')
-
-    default_server = os.environ.get('QMP_SOCKET')
-    parser.add_argument('qmp_server', action='store',
-                        default=default_server,
-                        help='< UNIX socket path | TCP address:port >')
-
-    args = parser.parse_args()
-    if args.qmp_server is None:
-        parser.error("QMP socket or TCP address must be specified")
-
-    shell_class = HMPShell if args.hmp else QMPShell
-
-    try:
-        address = shell_class.parse_address(args.qmp_server)
-    except qmp.QMPBadPortError:
-        parser.error(f"Bad port number: {args.qmp_server}")
-        return  # pycharm doesn't know error() is noreturn
-
-    with shell_class(address, args.pretty, args.verbose) as qemu:
-        try:
-            qemu.connect(negotiate=not args.skip_negotiation)
-        except qmp.QMPConnectError:
-            die("Didn't get QMP greeting message")
-        except qmp.QMPCapabilitiesError:
-            die("Couldn't negotiate capabilities")
-        except OSError as err:
-            die(f"Couldn't connect to {args.qmp_server}: {err!s}")
-
-        for _ in qemu.repl():
-            pass
-
-
-if __name__ == '__main__':
-    main()