Robert O'Callahan 4f297566b3 [lldb] Implement basic support for reverse-continue (#99736)
This commit only adds support for the
`SBProcess::ReverseContinue()` API. A user-accessible command for this
will follow in a later commit.

This feature depends on a gdbserver implementation (e.g. `rr`) providing
support for the `bc` and `bs` packets. `lldb-server` does not support
those packets, and there is no plan to change that. So, for testing
purposes, `lldbreverse.py` wraps `lldb-server` with a Python
implementation of *very limited* record-and-replay functionality for use
by *tests only*.

The majority of this PR is test infrastructure (about 700 of the 950
lines added).
2024-10-10 16:08:19 -07:00

176 lines
6.4 KiB
Python

import logging
import os
import os.path
import random
import lldb
from lldbsuite.test.lldbtest import *
from lldbsuite.test.gdbclientutils import *
import lldbgdbserverutils
from lldbsuite.support import seven
class GDBProxyTestBase(TestBase):
"""
Base class for gdbserver proxy tests.
This class will setup and start a mock GDB server for the test to use.
It pases through requests to a regular lldb-server/debugserver and
forwards replies back to the LLDB under test.
"""
"""The gdbserver that we implement."""
server = None
"""The inner lldb-server/debugserver process that we proxy requests into."""
monitor_server = None
monitor_sock = None
server_socket_class = TCPServerSocket
DEFAULT_TIMEOUT = 20 * (10 if ("ASAN_OPTIONS" in os.environ) else 1)
_verbose_log_handler = None
_log_formatter = logging.Formatter(fmt="%(asctime)-15s %(levelname)-8s %(message)s")
def setUpBaseLogging(self):
self.logger = logging.getLogger(__name__)
if len(self.logger.handlers) > 0:
return # We have set up this handler already
self.logger.propagate = False
self.logger.setLevel(logging.DEBUG)
# log all warnings to stderr
handler = logging.StreamHandler()
handler.setLevel(logging.WARNING)
handler.setFormatter(self._log_formatter)
self.logger.addHandler(handler)
def setUp(self):
TestBase.setUp(self)
self.setUpBaseLogging()
if self.isVerboseLoggingRequested():
# If requested, full logs go to a log file
log_file_name = self.getLogBasenameForCurrentTest() + "-proxy.log"
self._verbose_log_handler = logging.FileHandler(
log_file_name
)
self._verbose_log_handler.setFormatter(self._log_formatter)
self._verbose_log_handler.setLevel(logging.DEBUG)
self.logger.addHandler(self._verbose_log_handler)
lldb_server_exe = lldbgdbserverutils.get_lldb_server_exe()
if lldb_server_exe is None:
self.debug_monitor_exe = lldbgdbserverutils.get_debugserver_exe()
self.assertTrue(self.debug_monitor_exe is not None)
self.debug_monitor_extra_args = []
else:
self.debug_monitor_exe = lldb_server_exe
self.debug_monitor_extra_args = ["gdbserver"]
self.server = MockGDBServer(self.server_socket_class())
self.server.responder = self
def tearDown(self):
# TestBase.tearDown will kill the process, but we need to kill it early
# so its client connection closes and we can stop the server before
# finally calling the base tearDown.
if self.process() is not None:
self.process().Kill()
self.server.stop()
self.logger.removeHandler(self._verbose_log_handler)
self._verbose_log_handler = None
TestBase.tearDown(self)
def isVerboseLoggingRequested(self):
# We will report our detailed logs if the user requested that the "gdb-remote" channel is
# logged.
return any(("gdb-remote" in channel) for channel in lldbtest_config.channels)
def connect(self, target):
"""
Create a process by connecting to the mock GDB server.
"""
self.prep_debug_monitor_and_inferior()
self.server.start()
listener = self.dbg.GetListener()
error = lldb.SBError()
process = target.ConnectRemote(
listener, self.server.get_connect_url(), "gdb-remote", error
)
self.assertTrue(error.Success(), error.description)
self.assertTrue(process, PROCESS_IS_VALID)
return process
def get_next_port(self):
return 12000 + random.randint(0, 3999)
def prep_debug_monitor_and_inferior(self):
inferior_exe_path = self.getBuildArtifact("a.out")
self.connect_to_debug_monitor([inferior_exe_path])
self.assertIsNotNone(self.monitor_server)
self.initial_handshake()
def initial_handshake(self):
self.monitor_server.send_packet(seven.bitcast_to_bytes("+"))
reply = seven.bitcast_to_string(self.monitor_server.get_normal_packet())
self.assertEqual(reply, "+")
self.monitor_server.send_packet(seven.bitcast_to_bytes("QStartNoAckMode"))
reply = seven.bitcast_to_string(self.monitor_server.get_normal_packet())
self.assertEqual(reply, "+")
reply = seven.bitcast_to_string(self.monitor_server.get_normal_packet())
self.assertEqual(reply, "OK")
self.monitor_server.send_packet(seven.bitcast_to_bytes("+"))
reply = seven.bitcast_to_string(self.monitor_server.get_normal_packet())
self.assertEqual(reply, "+")
def get_debug_monitor_command_line_args(self, connect_address, launch_args):
return self.debug_monitor_extra_args + ["--reverse-connect", connect_address] + launch_args
def launch_debug_monitor(self, launch_args):
family, type, proto, _, addr = socket.getaddrinfo(
"localhost", 0, proto=socket.IPPROTO_TCP
)[0]
sock = socket.socket(family, type, proto)
sock.settimeout(self.DEFAULT_TIMEOUT)
sock.bind(addr)
sock.listen(1)
addr = sock.getsockname()
connect_address = "[{}]:{}".format(*addr)
commandline_args = self.get_debug_monitor_command_line_args(
connect_address, launch_args
)
# Start the server.
self.logger.info(f"Spawning monitor {commandline_args}")
monitor_process = self.spawnSubprocess(
self.debug_monitor_exe, commandline_args, install_remote=False
)
self.assertIsNotNone(monitor_process)
self.monitor_sock = sock.accept()[0]
self.monitor_sock.settimeout(self.DEFAULT_TIMEOUT)
return monitor_process
def connect_to_debug_monitor(self, launch_args):
monitor_process = self.launch_debug_monitor(launch_args)
self.monitor_server = lldbgdbserverutils.Server(self.monitor_sock, monitor_process)
def respond(self, packet):
"""Subclasses can override this to change how packets are handled."""
return self.pass_through(packet)
def pass_through(self, packet):
self.logger.info(f"Sending packet {packet}")
self.monitor_server.send_packet(seven.bitcast_to_bytes(packet))
reply = seven.bitcast_to_string(self.monitor_server.get_normal_packet())
self.logger.info(f"Received reply {reply}")
return reply