tools/lldb-server/TestLldbGdbServer.py

"""
Test case for testing the gdbremote protocol.

Tests run against debugserver and lldb-server (llgs).
lldb-server tests run where the lldb-server exe is
available.

This class will be broken into smaller test case classes by
gdb remote packet functional areas.  For now it contains
the initial set of tests implemented.
"""

import unittest2
import gdbremote_testcase
import lldbgdbserverutils
from lldbsuite.support import seven
from lldbsuite.test.decorators import *
from lldbsuite.test.lldbtest import *
from lldbsuite.test.lldbdwarf import *
from lldbsuite.test import lldbutil


class LldbGdbServerTestCase(gdbremote_testcase.GdbRemoteTestCaseBase, DwarfOpcodeParser):

    mydir = TestBase.compute_mydir(__file__)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_exe_starts_debugserver(self):
        self.init_debugserver_test()
        server = self.connect_to_debug_monitor()

    @llgs_test
    def test_exe_starts_llgs(self):
        self.init_llgs_test()
        server = self.connect_to_debug_monitor()

    def start_no_ack_mode(self):
        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        self.add_no_ack_remote_stream()
        self.expect_gdbremote_sequence()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_start_no_ack_mode_debugserver(self):
        self.init_debugserver_test()
        self.start_no_ack_mode()

    @llgs_test
    def test_start_no_ack_mode_llgs(self):
        self.init_llgs_test()
        self.start_no_ack_mode()

    def thread_suffix_supported(self):
        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        self.add_no_ack_remote_stream()
        self.test_sequence.add_log_lines(
            ["lldb-server <  26> read packet: $QThreadSuffixSupported#e4",
             "lldb-server <   6> send packet: $OK#9a"],
            True)

        self.expect_gdbremote_sequence()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_thread_suffix_supported_debugserver(self):
        self.init_debugserver_test()
        self.thread_suffix_supported()

    @llgs_test
    def test_thread_suffix_supported_llgs(self):
        self.init_llgs_test()
        self.thread_suffix_supported()

    def list_threads_in_stop_reply_supported(self):
        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        self.add_no_ack_remote_stream()
        self.test_sequence.add_log_lines(
            ["lldb-server <  27> read packet: $QListThreadsInStopReply#21",
             "lldb-server <   6> send packet: $OK#9a"],
            True)
        self.expect_gdbremote_sequence()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_list_threads_in_stop_reply_supported_debugserver(self):
        self.init_debugserver_test()
        self.list_threads_in_stop_reply_supported()

    @llgs_test
    def test_list_threads_in_stop_reply_supported_llgs(self):
        self.init_llgs_test()
        self.list_threads_in_stop_reply_supported()

    def c_packet_works(self):
        launch_args = self.install_and_create_launch_args()

        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        self.add_no_ack_remote_stream()
        self.add_verified_launch_packets(launch_args)
        self.test_sequence.add_log_lines(
            ["read packet: $c#63",
             "send packet: $W00#00"],
            True)

        self.expect_gdbremote_sequence()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_c_packet_works_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.c_packet_works()

    @llgs_test
    def test_c_packet_works_llgs(self):
        self.init_llgs_test()
        self.build()
        self.c_packet_works()

    def inferior_print_exit(self):
        launch_args = self.install_and_create_launch_args()

        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        # build launch args
        launch_args += ["hello, world"]

        self.add_no_ack_remote_stream()
        self.add_verified_launch_packets(launch_args)
        self.test_sequence.add_log_lines(
            ["read packet: $vCont;c#a8",
             {"type": "output_match", "regex": self.maybe_strict_output_regex(r"hello, world\r\n")},
             "send packet: $W00#00"],
            True)

        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_inferior_print_exit_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.inferior_print_exit()

    @skipIfWindows # No pty support to test any inferior output
    @llgs_test
    @expectedFlakeyLinux("llvm.org/pr25652")
    def test_inferior_print_exit_llgs(self):
        self.init_llgs_test()
        self.build()
        self.inferior_print_exit()

    def first_launch_stop_reply_thread_matches_first_qC(self):
        launch_args = self.install_and_create_launch_args()

        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        # build launch args
        launch_args += ["hello, world"]

        self.add_no_ack_remote_stream()
        self.add_verified_launch_packets(launch_args)
        self.test_sequence.add_log_lines(["read packet: $qC#00",
                                          {"direction": "send",
                                           "regex": r"^\$QC([0-9a-fA-F]+)#",
                                           "capture": {1: "thread_id"}},
                                          "read packet: $?#00",
                                          {"direction": "send",
                                              "regex": r"^\$T[0-9a-fA-F]{2}thread:([0-9a-fA-F]+)",
                                              "expect_captures": {1: "thread_id"}}],
                                         True)
        self.expect_gdbremote_sequence()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_first_launch_stop_reply_thread_matches_first_qC_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.first_launch_stop_reply_thread_matches_first_qC()

    @llgs_test
    def test_first_launch_stop_reply_thread_matches_first_qC_llgs(self):
        self.init_llgs_test()
        self.build()
        self.first_launch_stop_reply_thread_matches_first_qC()

    def attach_commandline_continue_app_exits(self):
        procs = self.prep_debug_monitor_and_inferior()
        self.test_sequence.add_log_lines(
            ["read packet: $vCont;c#a8",
             "send packet: $W00#00"],
            True)
        self.expect_gdbremote_sequence()

        # Wait a moment for completed and now-detached inferior process to
        # clear.
        time.sleep(1)

        if not lldb.remote_platform:
            # Process should be dead now. Reap results.
            poll_result = procs["inferior"].poll()
            self.assertIsNotNone(poll_result)

        # Where possible, verify at the system level that the process is not
        # running.
        self.assertFalse(
            lldbgdbserverutils.process_is_running(
                procs["inferior"].pid, False))

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_attach_commandline_continue_app_exits_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_attach()
        self.attach_commandline_continue_app_exits()

    @llgs_test
    def test_attach_commandline_continue_app_exits_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_attach()
        self.attach_commandline_continue_app_exits()

    def qRegisterInfo_returns_one_valid_result(self):
        launch_args = self.install_and_create_launch_args()

        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        # Build the expected protocol stream
        self.add_no_ack_remote_stream()
        self.add_verified_launch_packets(launch_args)
        self.test_sequence.add_log_lines(
            ["read packet: $qRegisterInfo0#00",
             {"direction": "send", "regex": r"^\$(.+);#[0-9A-Fa-f]{2}", "capture": {1: "reginfo_0"}}],
            True)

        # Run the stream
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        reg_info_packet = context.get("reginfo_0")
        self.assertIsNotNone(reg_info_packet)
        self.assert_valid_reg_info(
            lldbgdbserverutils.parse_reg_info_response(reg_info_packet))

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qRegisterInfo_returns_one_valid_result_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.qRegisterInfo_returns_one_valid_result()

    @llgs_test
    def test_qRegisterInfo_returns_one_valid_result_llgs(self):
        self.init_llgs_test()
        self.build()
        self.qRegisterInfo_returns_one_valid_result()

    def qRegisterInfo_returns_all_valid_results(self):
        launch_args = self.install_and_create_launch_args()

        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        # Build the expected protocol stream.
        self.add_no_ack_remote_stream()
        self.add_verified_launch_packets(launch_args)
        self.add_register_info_collection_packets()

        # Run the stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Validate that each register info returned validates.
        for reg_info in self.parse_register_info_packets(context):
            self.assert_valid_reg_info(reg_info)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qRegisterInfo_returns_all_valid_results_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.qRegisterInfo_returns_all_valid_results()

    @llgs_test
    def test_qRegisterInfo_returns_all_valid_results_llgs(self):
        self.init_llgs_test()
        self.build()
        self.qRegisterInfo_returns_all_valid_results()

    def qRegisterInfo_contains_required_generics(self):
        launch_args = self.install_and_create_launch_args()

        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        # Build the expected protocol stream
        self.add_no_ack_remote_stream()
        self.add_verified_launch_packets(launch_args)
        self.add_register_info_collection_packets()

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Gather register info entries.
        reg_infos = self.parse_register_info_packets(context)

        # Collect all generic registers found.
        generic_regs = {
            reg_info['generic']: 1 for reg_info in reg_infos if 'generic' in reg_info}

        # Ensure we have a program counter register.
        self.assertTrue('pc' in generic_regs)

        # Ensure we have a frame pointer register. PPC64le's FP is the same as SP
        if self.getArchitecture() != 'powerpc64le':
            self.assertTrue('fp' in generic_regs)

        # Ensure we have a stack pointer register.
        self.assertTrue('sp' in generic_regs)

        # Ensure we have a flags register.
        self.assertTrue('flags' in generic_regs)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qRegisterInfo_contains_required_generics_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.qRegisterInfo_contains_required_generics()

    @llgs_test
    def test_qRegisterInfo_contains_required_generics_llgs(self):
        self.init_llgs_test()
        self.build()
        self.qRegisterInfo_contains_required_generics()

    def qRegisterInfo_contains_at_least_one_register_set(self):
        launch_args = self.install_and_create_launch_args()

        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        # Build the expected protocol stream
        self.add_no_ack_remote_stream()
        self.add_verified_launch_packets(launch_args)
        self.add_register_info_collection_packets()

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Gather register info entries.
        reg_infos = self.parse_register_info_packets(context)

        # Collect all register sets found.
        register_sets = {
            reg_info['set']: 1 for reg_info in reg_infos if 'set' in reg_info}
        self.assertTrue(len(register_sets) >= 1)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qRegisterInfo_contains_at_least_one_register_set_debugserver(
            self):
        self.init_debugserver_test()
        self.build()
        self.qRegisterInfo_contains_at_least_one_register_set()

    @llgs_test
    def test_qRegisterInfo_contains_at_least_one_register_set_llgs(self):
        self.init_llgs_test()
        self.build()
        self.qRegisterInfo_contains_at_least_one_register_set()

    def targetHasAVX(self):
        triple = self.dbg.GetSelectedPlatform().GetTriple()

        # TODO other platforms, please implement this function
        if not re.match(".*-.*-linux", triple):
            return True

        # Need to do something different for non-Linux/Android targets
        if lldb.remote_platform:
            self.runCmd('platform get-file "/proc/cpuinfo" "cpuinfo"')
            cpuinfo_path = "cpuinfo"
            self.addTearDownHook(lambda: os.unlink("cpuinfo"))
        else:
            cpuinfo_path = "/proc/cpuinfo"

        f = open(cpuinfo_path, 'r')
        cpuinfo = f.read()
        f.close()
        return " avx " in cpuinfo

    def qRegisterInfo_contains_avx_registers(self):
        launch_args = self.install_and_create_launch_args()

        server = self.connect_to_debug_monitor()
        self.assertIsNotNone(server)

        # Build the expected protocol stream
        self.add_no_ack_remote_stream()
        self.add_verified_launch_packets(launch_args)
        self.add_register_info_collection_packets()

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Gather register info entries.
        reg_infos = self.parse_register_info_packets(context)

        # Collect all generics found.
        register_sets = {
            reg_info['set']: 1 for reg_info in reg_infos if 'set' in reg_info}
        self.assertEqual(
            self.targetHasAVX(),
            "Advanced Vector Extensions" in register_sets)

    @expectedFailureAll(oslist=["windows"]) # no avx for now.
    @expectedFailureAll(oslist=["freebsd", "netbsd"])
    @llgs_test
    def test_qRegisterInfo_contains_avx_registers_llgs(self):
        self.init_llgs_test()
        self.build()
        self.qRegisterInfo_contains_avx_registers()

    def qThreadInfo_contains_thread(self):
        procs = self.prep_debug_monitor_and_inferior()
        self.add_threadinfo_collection_packets()

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Gather threadinfo entries.
        threads = self.parse_threadinfo_packets(context)
        self.assertIsNotNone(threads)

        # We should have exactly one thread.
        self.assertEqual(len(threads), 1)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qThreadInfo_contains_thread_launch_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qThreadInfo_contains_thread()

    @llgs_test
    def test_qThreadInfo_contains_thread_launch_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qThreadInfo_contains_thread()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qThreadInfo_contains_thread_attach_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_attach()
        self.qThreadInfo_contains_thread()

    @expectedFailureAll(oslist=["windows"]) # expect one more thread stopped
    @llgs_test
    def test_qThreadInfo_contains_thread_attach_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_attach()
        self.qThreadInfo_contains_thread()

    def qThreadInfo_matches_qC(self):
        procs = self.prep_debug_monitor_and_inferior()

        self.add_threadinfo_collection_packets()
        self.test_sequence.add_log_lines(
            ["read packet: $qC#00",
             {"direction": "send", "regex": r"^\$QC([0-9a-fA-F]+)#", "capture": {1: "thread_id"}}
             ], True)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Gather threadinfo entries.
        threads = self.parse_threadinfo_packets(context)
        self.assertIsNotNone(threads)

        # We should have exactly one thread from threadinfo.
        self.assertEqual(len(threads), 1)

        # We should have a valid thread_id from $QC.
        QC_thread_id_hex = context.get("thread_id")
        self.assertIsNotNone(QC_thread_id_hex)
        QC_thread_id = int(QC_thread_id_hex, 16)

        # Those two should be the same.
        self.assertEqual(threads[0], QC_thread_id)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qThreadInfo_matches_qC_launch_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qThreadInfo_matches_qC()

    @llgs_test
    def test_qThreadInfo_matches_qC_launch_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qThreadInfo_matches_qC()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qThreadInfo_matches_qC_attach_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_attach()
        self.qThreadInfo_matches_qC()

    @expectedFailureAll(oslist=["windows"]) # expect one more thread stopped
    @llgs_test
    def test_qThreadInfo_matches_qC_attach_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_attach()
        self.qThreadInfo_matches_qC()

    def p_returns_correct_data_size_for_each_qRegisterInfo(self):
        procs = self.prep_debug_monitor_and_inferior()
        self.add_register_info_collection_packets()

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Gather register info entries.
        reg_infos = self.parse_register_info_packets(context)
        self.assertIsNotNone(reg_infos)
        self.assertTrue(len(reg_infos) > 0)

        byte_order = self.get_target_byte_order()

        # Read value for each register.
        reg_index = 0
        for reg_info in reg_infos:
            # Skip registers that don't have a register set.  For x86, these are
            # the DRx registers, which have no LLDB-kind register number and thus
            # cannot be read via normal
            # NativeRegisterContext::ReadRegister(reg_info,...) calls.
            if not "set" in reg_info:
                continue

            # Clear existing packet expectations.
            self.reset_test_sequence()

            # Run the register query
            self.test_sequence.add_log_lines(
                ["read packet: $p{0:x}#00".format(reg_index),
                 {"direction": "send", "regex": r"^\$([0-9a-fA-F]+)#", "capture": {1: "p_response"}}],
                True)
            context = self.expect_gdbremote_sequence()
            self.assertIsNotNone(context)

            # Verify the response length.
            p_response = context.get("p_response")
            self.assertIsNotNone(p_response)

            if "dynamic_size_dwarf_expr_bytes" in reg_info:
                self.updateRegInfoBitsize(reg_info, byte_order)
            self.assertEqual(len(p_response), 2 * int(reg_info["bitsize"]) / 8)

            # Increment loop
            reg_index += 1

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_p_returns_correct_data_size_for_each_qRegisterInfo_launch_debugserver(
            self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.p_returns_correct_data_size_for_each_qRegisterInfo()

    @expectedFailureAll(oslist=["freebsd", "netbsd"])
    @llgs_test
    def test_p_returns_correct_data_size_for_each_qRegisterInfo_launch_llgs(
            self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.p_returns_correct_data_size_for_each_qRegisterInfo()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_p_returns_correct_data_size_for_each_qRegisterInfo_attach_debugserver(
            self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_attach()
        self.p_returns_correct_data_size_for_each_qRegisterInfo()

    @expectedFailureAll(oslist=["freebsd", "netbsd"])
    @llgs_test
    def test_p_returns_correct_data_size_for_each_qRegisterInfo_attach_llgs(
            self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_attach()
        self.p_returns_correct_data_size_for_each_qRegisterInfo()

    def Hg_switches_to_3_threads(self):
        # Startup the inferior with three threads (main + 2 new ones).
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=["thread:new", "thread:new"])

        # Let the inferior process have a few moments to start up the thread
        # when launched.  (The launch scenario has no time to run, so threads
        # won't be there yet.)
        self.run_process_then_stop(run_seconds=1)

        # Wait at most x seconds for 3 threads to be present.
        threads = self.wait_for_thread_count(3)
        self.assertEqual(len(threads), 3)

        # verify we can $H to each thead, and $qC matches the thread we set.
        for thread in threads:
            # Change to each thread, verify current thread id.
            self.reset_test_sequence()
            self.test_sequence.add_log_lines(
                ["read packet: $Hg{0:x}#00".format(thread),  # Set current thread.
                 "send packet: $OK#00",
                 "read packet: $qC#00",
                 {"direction": "send", "regex": r"^\$QC([0-9a-fA-F]+)#", "capture": {1: "thread_id"}}],
                True)

            context = self.expect_gdbremote_sequence()
            self.assertIsNotNone(context)

            # Verify the thread id.
            self.assertIsNotNone(context.get("thread_id"))
            self.assertEqual(int(context.get("thread_id"), 16), thread)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_Hg_switches_to_3_threads_launch_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.Hg_switches_to_3_threads()

    @expectedFailureAll(oslist=["windows"]) # expect 4 threads
    @llgs_test
    def test_Hg_switches_to_3_threads_launch_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.Hg_switches_to_3_threads()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_Hg_switches_to_3_threads_attach_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_attach()
        self.Hg_switches_to_3_threads()

    @expectedFailureAll(oslist=["windows"]) # expecting one more thread
    @llgs_test
    def test_Hg_switches_to_3_threads_attach_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_attach()
        self.Hg_switches_to_3_threads()

    def Hc_then_Csignal_signals_correct_thread(self, segfault_signo):
        # NOTE only run this one in inferior-launched mode: we can't grab inferior stdout when running attached,
        # and the test requires getting stdout from the exe.

        NUM_THREADS = 3

        # Startup the inferior with three threads (main + NUM_THREADS-1 worker threads).
        # inferior_args=["thread:print-ids"]
        inferior_args = ["thread:segfault"]
        for i in range(NUM_THREADS - 1):
            # if i > 0:
                # Give time between thread creation/segfaulting for the handler to work.
                # inferior_args.append("sleep:1")
            inferior_args.append("thread:new")
        inferior_args.append("sleep:10")

        # Launch/attach.  (In our case, this should only ever be launched since
        # we need inferior stdout/stderr).
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=inferior_args)
        self.test_sequence.add_log_lines(["read packet: $c#63"], True)
        context = self.expect_gdbremote_sequence()

        # Let the inferior process have a few moments to start up the thread when launched.
        # context = self.run_process_then_stop(run_seconds=1)

        # Wait at most x seconds for all threads to be present.
        # threads = self.wait_for_thread_count(NUM_THREADS)
        # self.assertEquals(len(threads), NUM_THREADS)

        signaled_tids = {}
        print_thread_ids = {}

        # Switch to each thread, deliver a signal, and verify signal delivery
        for i in range(NUM_THREADS - 1):
            # Run until SIGSEGV comes in.
            self.reset_test_sequence()
            self.test_sequence.add_log_lines([{"direction": "send",
                                               "regex": r"^\$T([0-9a-fA-F]{2})thread:([0-9a-fA-F]+);",
                                               "capture": {1: "signo",
                                                            2: "thread_id"}}],
                                             True)

            context = self.expect_gdbremote_sequence()
            self.assertIsNotNone(context)
            signo = context.get("signo")
            self.assertEqual(int(signo, 16), segfault_signo)

            # Ensure we haven't seen this tid yet.
            thread_id = int(context.get("thread_id"), 16)
            self.assertFalse(thread_id in signaled_tids)
            signaled_tids[thread_id] = 1

            # Send SIGUSR1 to the thread that signaled the SIGSEGV.
            self.reset_test_sequence()
            self.test_sequence.add_log_lines(
                [
                    # Set the continue thread.
                    # Set current thread.
                    "read packet: $Hc{0:x}#00".format(thread_id),
                    "send packet: $OK#00",

                    # Continue sending the signal number to the continue thread.
                    # The commented out packet is a way to do this same operation without using
                    # a $Hc (but this test is testing $Hc, so we'll stick with the former).
                    "read packet: $C{0:x}#00".format(lldbutil.get_signal_number('SIGUSR1')),
                    # "read packet: $vCont;C{0:x}:{1:x};c#00".format(lldbutil.get_signal_number('SIGUSR1'), thread_id),

                    # FIXME: Linux does not report the thread stop on the delivered signal (SIGUSR1 here).  MacOSX debugserver does.
                    # But MacOSX debugserver isn't guaranteeing the thread the signal handler runs on, so currently its an XFAIL.
                    # Need to rectify behavior here.  The linux behavior is more intuitive to me since we're essentially swapping out
                    # an about-to-be-delivered signal (for which we already sent a stop packet) to a different signal.
                    # {"direction":"send", "regex":r"^\$T([0-9a-fA-F]{2})thread:([0-9a-fA-F]+);", "capture":{1:"stop_signo", 2:"stop_thread_id"} },
                    #  "read packet: $c#63",
                    {"type": "output_match", "regex": r"^received SIGUSR1 on thread id: ([0-9a-fA-F]+)\r\nthread ([0-9a-fA-F]+): past SIGSEGV\r\n", "capture": {1: "print_thread_id", 2: "post_handle_thread_id"}},
                ],
                True)

            # Run the sequence.
            context = self.expect_gdbremote_sequence()
            self.assertIsNotNone(context)

            # Ensure the stop signal is the signal we delivered.
            # stop_signo = context.get("stop_signo")
            # self.assertIsNotNone(stop_signo)
            # self.assertEquals(int(stop_signo,16), lldbutil.get_signal_number('SIGUSR1'))

            # Ensure the stop thread is the thread to which we delivered the signal.
            # stop_thread_id = context.get("stop_thread_id")
            # self.assertIsNotNone(stop_thread_id)
            # self.assertEquals(int(stop_thread_id,16), thread_id)

            # Ensure we haven't seen this thread id yet.  The inferior's
            # self-obtained thread ids are not guaranteed to match the stub
            # tids (at least on MacOSX).
            print_thread_id = context.get("print_thread_id")
            self.assertIsNotNone(print_thread_id)
            print_thread_id = int(print_thread_id, 16)
            self.assertFalse(print_thread_id in print_thread_ids)

            # Now remember this print (i.e. inferior-reflected) thread id and
            # ensure we don't hit it again.
            print_thread_ids[print_thread_id] = 1

            # Ensure post signal-handle thread id matches the thread that
            # initially raised the SIGSEGV.
            post_handle_thread_id = context.get("post_handle_thread_id")
            self.assertIsNotNone(post_handle_thread_id)
            post_handle_thread_id = int(post_handle_thread_id, 16)
            self.assertEqual(post_handle_thread_id, print_thread_id)

    @expectedFailure
    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_Hc_then_Csignal_signals_correct_thread_launch_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        # Darwin debugserver translates some signals like SIGSEGV into some gdb
        # expectations about fixed signal numbers.
        self.Hc_then_Csignal_signals_correct_thread(self.TARGET_EXC_BAD_ACCESS)

    @skipIfWindows # no SIGSEGV support
    @expectedFailureAll(oslist=["freebsd", "netbsd"])
    @llgs_test
    def test_Hc_then_Csignal_signals_correct_thread_launch_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.Hc_then_Csignal_signals_correct_thread(
            lldbutil.get_signal_number('SIGSEGV'))

    def m_packet_reads_memory(self):
        # This is the memory we will write into the inferior and then ensure we
        # can read back with $m.
        MEMORY_CONTENTS = "Test contents 0123456789 ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz"

        # Start up the inferior.
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=[
                "set-message:%s" %
                MEMORY_CONTENTS,
                "get-data-address-hex:g_message",
                "sleep:5"])

        # Run the process
        self.test_sequence.add_log_lines(
            [
                # Start running after initial stop.
                "read packet: $c#63",
                # Match output line that prints the memory address of the message buffer within the inferior.
                # Note we require launch-only testing so we can get inferior otuput.
                {"type": "output_match", "regex": self.maybe_strict_output_regex(r"data address: 0x([0-9a-fA-F]+)\r\n"),
                 "capture": {1: "message_address"}},
                # Now stop the inferior.
                "read packet: {}".format(chr(3)),
                # And wait for the stop notification.
                {"direction": "send", "regex": r"^\$T([0-9a-fA-F]{2})thread:([0-9a-fA-F]+);", "capture": {1: "stop_signo", 2: "stop_thread_id"}}],
            True)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Grab the message address.
        self.assertIsNotNone(context.get("message_address"))
        message_address = int(context.get("message_address"), 16)

        # Grab contents from the inferior.
        self.reset_test_sequence()
        self.test_sequence.add_log_lines(
            ["read packet: $m{0:x},{1:x}#00".format(message_address, len(MEMORY_CONTENTS)),
             {"direction": "send", "regex": r"^\$(.+)#[0-9a-fA-F]{2}$", "capture": {1: "read_contents"}}],
            True)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Ensure what we read from inferior memory is what we wrote.
        self.assertIsNotNone(context.get("read_contents"))
        read_contents = seven.unhexlify(context.get("read_contents"))
        self.assertEqual(read_contents, MEMORY_CONTENTS)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_m_packet_reads_memory_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.m_packet_reads_memory()

    @skipIfWindows # No pty support to test any inferior output
    @llgs_test
    def test_m_packet_reads_memory_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.m_packet_reads_memory()

    def qMemoryRegionInfo_is_supported(self):
        # Start up the inferior.
        procs = self.prep_debug_monitor_and_inferior()

        # Ask if it supports $qMemoryRegionInfo.
        self.test_sequence.add_log_lines(
            ["read packet: $qMemoryRegionInfo#00",
             "send packet: $OK#00"
             ], True)
        self.expect_gdbremote_sequence()

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qMemoryRegionInfo_is_supported_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qMemoryRegionInfo_is_supported()

    @llgs_test
    @expectedFailureAll(oslist=["freebsd"])
    def test_qMemoryRegionInfo_is_supported_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qMemoryRegionInfo_is_supported()

    def qMemoryRegionInfo_reports_code_address_as_executable(self):
        # Start up the inferior.
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=["get-code-address-hex:hello", "sleep:5"])

        # Run the process
        self.test_sequence.add_log_lines(
            [
                # Start running after initial stop.
                "read packet: $c#63",
                # Match output line that prints the memory address of the message buffer within the inferior.
                # Note we require launch-only testing so we can get inferior otuput.
                {"type": "output_match", "regex": self.maybe_strict_output_regex(r"code address: 0x([0-9a-fA-F]+)\r\n"),
                 "capture": {1: "code_address"}},
                # Now stop the inferior.
                "read packet: {}".format(chr(3)),
                # And wait for the stop notification.
                {"direction": "send", "regex": r"^\$T([0-9a-fA-F]{2})thread:([0-9a-fA-F]+);", "capture": {1: "stop_signo", 2: "stop_thread_id"}}],
            True)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Grab the code address.
        self.assertIsNotNone(context.get("code_address"))
        code_address = int(context.get("code_address"), 16)

        # Grab memory region info from the inferior.
        self.reset_test_sequence()
        self.add_query_memory_region_packets(code_address)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)
        mem_region_dict = self.parse_memory_region_packet(context)

        # Ensure there are no errors reported.
        self.assertFalse("error" in mem_region_dict)

        # Ensure code address is readable and executable.
        self.assertTrue("permissions" in mem_region_dict)
        self.assertTrue("r" in mem_region_dict["permissions"])
        self.assertTrue("x" in mem_region_dict["permissions"])

        # Ensure the start address and size encompass the address we queried.
        self.assert_address_within_memory_region(code_address, mem_region_dict)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qMemoryRegionInfo_reports_code_address_as_executable_debugserver(
            self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qMemoryRegionInfo_reports_code_address_as_executable()

    @skipIfWindows # No pty support to test any inferior output
    @expectedFailureAll(oslist=["freebsd"])
    @llgs_test
    def test_qMemoryRegionInfo_reports_code_address_as_executable_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qMemoryRegionInfo_reports_code_address_as_executable()

    def qMemoryRegionInfo_reports_stack_address_as_readable_writeable(self):
        # Start up the inferior.
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=["get-stack-address-hex:", "sleep:5"])

        # Run the process
        self.test_sequence.add_log_lines(
            [
                # Start running after initial stop.
                "read packet: $c#63",
                # Match output line that prints the memory address of the message buffer within the inferior.
                # Note we require launch-only testing so we can get inferior otuput.
                {"type": "output_match", "regex": self.maybe_strict_output_regex(r"stack address: 0x([0-9a-fA-F]+)\r\n"),
                 "capture": {1: "stack_address"}},
                # Now stop the inferior.
                "read packet: {}".format(chr(3)),
                # And wait for the stop notification.
                {"direction": "send", "regex": r"^\$T([0-9a-fA-F]{2})thread:([0-9a-fA-F]+);", "capture": {1: "stop_signo", 2: "stop_thread_id"}}],
            True)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Grab the address.
        self.assertIsNotNone(context.get("stack_address"))
        stack_address = int(context.get("stack_address"), 16)

        # Grab memory region info from the inferior.
        self.reset_test_sequence()
        self.add_query_memory_region_packets(stack_address)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)
        mem_region_dict = self.parse_memory_region_packet(context)

        # Ensure there are no errors reported.
        self.assertFalse("error" in mem_region_dict)

        # Ensure address is readable and executable.
        self.assertTrue("permissions" in mem_region_dict)
        self.assertTrue("r" in mem_region_dict["permissions"])
        self.assertTrue("w" in mem_region_dict["permissions"])

        # Ensure the start address and size encompass the address we queried.
        self.assert_address_within_memory_region(
            stack_address, mem_region_dict)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qMemoryRegionInfo_reports_stack_address_as_readable_writeable_debugserver(
            self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qMemoryRegionInfo_reports_stack_address_as_readable_writeable()

    @skipIfWindows # No pty support to test any inferior output
    @expectedFailureAll(oslist=["freebsd"])
    @llgs_test
    def test_qMemoryRegionInfo_reports_stack_address_as_readable_writeable_llgs(
            self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qMemoryRegionInfo_reports_stack_address_as_readable_writeable()

    def qMemoryRegionInfo_reports_heap_address_as_readable_writeable(self):
        # Start up the inferior.
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=["get-heap-address-hex:", "sleep:5"])

        # Run the process
        self.test_sequence.add_log_lines(
            [
                # Start running after initial stop.
                "read packet: $c#63",
                # Match output line that prints the memory address of the message buffer within the inferior.
                # Note we require launch-only testing so we can get inferior otuput.
                {"type": "output_match", "regex": self.maybe_strict_output_regex(r"heap address: 0x([0-9a-fA-F]+)\r\n"),
                 "capture": {1: "heap_address"}},
                # Now stop the inferior.
                "read packet: {}".format(chr(3)),
                # And wait for the stop notification.
                {"direction": "send", "regex": r"^\$T([0-9a-fA-F]{2})thread:([0-9a-fA-F]+);", "capture": {1: "stop_signo", 2: "stop_thread_id"}}],
            True)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Grab the address.
        self.assertIsNotNone(context.get("heap_address"))
        heap_address = int(context.get("heap_address"), 16)

        # Grab memory region info from the inferior.
        self.reset_test_sequence()
        self.add_query_memory_region_packets(heap_address)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)
        mem_region_dict = self.parse_memory_region_packet(context)

        # Ensure there are no errors reported.
        self.assertFalse("error" in mem_region_dict)

        # Ensure address is readable and executable.
        self.assertTrue("permissions" in mem_region_dict)
        self.assertTrue("r" in mem_region_dict["permissions"])
        self.assertTrue("w" in mem_region_dict["permissions"])

        # Ensure the start address and size encompass the address we queried.
        self.assert_address_within_memory_region(heap_address, mem_region_dict)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qMemoryRegionInfo_reports_heap_address_as_readable_writeable_debugserver(
            self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qMemoryRegionInfo_reports_heap_address_as_readable_writeable()

    @skipIfWindows # No pty support to test any inferior output
    @expectedFailureAll(oslist=["freebsd"])
    @llgs_test
    def test_qMemoryRegionInfo_reports_heap_address_as_readable_writeable_llgs(
            self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qMemoryRegionInfo_reports_heap_address_as_readable_writeable()

    def breakpoint_set_and_remove_work(self, want_hardware=False):
        # Start up the inferior.
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=[
                "get-code-address-hex:hello",
                "sleep:1",
                "call-function:hello"])

        # Run the process
        self.add_register_info_collection_packets()
        self.add_process_info_collection_packets()
        self.test_sequence.add_log_lines(
            [  # Start running after initial stop.
                "read packet: $c#63",
                # Match output line that prints the memory address of the function call entry point.
                # Note we require launch-only testing so we can get inferior otuput.
                {"type": "output_match", "regex": self.maybe_strict_output_regex(r"code address: 0x([0-9a-fA-F]+)\r\n"),
                 "capture": {1: "function_address"}},
                # Now stop the inferior.
                "read packet: {}".format(chr(3)),
                # And wait for the stop notification.
                {"direction": "send", "regex": r"^\$T([0-9a-fA-F]{2})thread:([0-9a-fA-F]+);", "capture": {1: "stop_signo", 2: "stop_thread_id"}}],
            True)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Gather process info - we need endian of target to handle register
        # value conversions.
        process_info = self.parse_process_info_response(context)
        endian = process_info.get("endian")
        self.assertIsNotNone(endian)

        # Gather register info entries.
        reg_infos = self.parse_register_info_packets(context)
        (pc_lldb_reg_index, pc_reg_info) = self.find_pc_reg_info(reg_infos)
        self.assertIsNotNone(pc_lldb_reg_index)
        self.assertIsNotNone(pc_reg_info)

        # Grab the function address.
        self.assertIsNotNone(context.get("function_address"))
        function_address = int(context.get("function_address"), 16)

        # Get current target architecture
        target_arch = self.getArchitecture()

        # Set the breakpoint.
        if (target_arch == "arm") or (target_arch == "aarch64"):
            # TODO: Handle case when setting breakpoint in thumb code
            BREAKPOINT_KIND = 4
        else:
            BREAKPOINT_KIND = 1

        # Set default packet type to Z0 (software breakpoint)
        z_packet_type = 0

        # If hardware breakpoint is requested set packet type to Z1
        if want_hardware == True:
            z_packet_type = 1

        self.reset_test_sequence()
        self.add_set_breakpoint_packets(
            function_address,
            z_packet_type,
            do_continue=True,
            breakpoint_kind=BREAKPOINT_KIND)

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Verify the stop signal reported was the breakpoint signal number.
        stop_signo = context.get("stop_signo")
        self.assertIsNotNone(stop_signo)
        self.assertEqual(int(stop_signo, 16),
                         lldbutil.get_signal_number('SIGTRAP'))

        # Ensure we did not receive any output.  If the breakpoint was not set, we would
        # see output (from a launched process with captured stdio) printing a hello, world message.
        # That would indicate the breakpoint didn't take.
        self.assertEqual(len(context["O_content"]), 0)

        # Verify that the PC for the main thread is where we expect it - right at the breakpoint address.
        # This acts as a another validation on the register reading code.
        self.reset_test_sequence()
        self.test_sequence.add_log_lines(
            [
                # Print the PC.  This should match the breakpoint address.
                "read packet: $p{0:x}#00".format(pc_lldb_reg_index),
                # Capture $p results.
                {"direction": "send",
                 "regex": r"^\$([0-9a-fA-F]+)#",
                 "capture": {1: "p_response"}},
            ], True)

        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Verify the PC is where we expect.  Note response is in endianness of
        # the inferior.
        p_response = context.get("p_response")
        self.assertIsNotNone(p_response)

        # Convert from target endian to int.
        returned_pc = lldbgdbserverutils.unpack_register_hex_unsigned(
            endian, p_response)
        self.assertEqual(returned_pc, function_address)

        # Verify that a breakpoint remove and continue gets us the expected
        # output.
        self.reset_test_sequence()

        # Add breakpoint remove packets
        self.add_remove_breakpoint_packets(
            function_address,
            z_packet_type,
            breakpoint_kind=BREAKPOINT_KIND)

        self.test_sequence.add_log_lines(
            [
                # Continue running.
                "read packet: $c#63",
                # We should now receive the output from the call.
                {"type": "output_match", "regex": r"^hello, world\r\n$"},
                # And wait for program completion.
                {"direction": "send", "regex": r"^\$W00(.*)#[0-9a-fA-F]{2}$"},
            ], True)

        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_software_breakpoint_set_and_remove_work_debugserver(self):
        self.init_debugserver_test()
        if self.getArchitecture() == "arm":
            # TODO: Handle case when setting breakpoint in thumb code
            self.build(dictionary={'CFLAGS_EXTRAS': '-marm'})
        else:
            self.build()
        self.set_inferior_startup_launch()
        self.breakpoint_set_and_remove_work(want_hardware=False)

    @skipIfWindows # No pty support to test any inferior output
    @llgs_test
    @expectedFlakeyLinux("llvm.org/pr25652")
    def test_software_breakpoint_set_and_remove_work_llgs(self):
        self.init_llgs_test()
        if self.getArchitecture() == "arm":
            # TODO: Handle case when setting breakpoint in thumb code
            self.build(dictionary={'CFLAGS_EXTRAS': '-marm'})
        else:
            self.build()
        self.set_inferior_startup_launch()
        self.breakpoint_set_and_remove_work(want_hardware=False)

    @debugserver_test
    @skipUnlessPlatform(oslist=['linux'])
    @expectedFailureAndroid
    @skipIf(archs=no_match(['arm', 'aarch64']))
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_hardware_breakpoint_set_and_remove_work_debugserver(self):
        self.init_debugserver_test()
        if self.getArchitecture() == "arm":
            # TODO: Handle case when setting breakpoint in thumb code
            self.build(dictionary={'CFLAGS_EXTRAS': '-marm'})
        else:
            self.build()
        self.set_inferior_startup_launch()
        self.breakpoint_set_and_remove_work(want_hardware=True)

    @llgs_test
    @skipUnlessPlatform(oslist=['linux'])
    @skipIf(archs=no_match(['arm', 'aarch64']))
    def test_hardware_breakpoint_set_and_remove_work_llgs(self):
        self.init_llgs_test()
        if self.getArchitecture() == "arm":
            # TODO: Handle case when setting breakpoint in thumb code
            self.build(dictionary={'CFLAGS_EXTRAS': '-marm'})
        else:
            self.build()
        self.set_inferior_startup_launch()
        self.breakpoint_set_and_remove_work(want_hardware=True)

    def qSupported_returns_known_stub_features(self):
        # Start up the stub and start/prep the inferior.
        procs = self.prep_debug_monitor_and_inferior()
        self.add_qSupported_packets()

        # Run the packet stream.
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Retrieve the qSupported features.
        supported_dict = self.parse_qSupported_response(context)
        self.assertIsNotNone(supported_dict)
        self.assertTrue(len(supported_dict) > 0)

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_qSupported_returns_known_stub_features_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qSupported_returns_known_stub_features()

    @llgs_test
    def test_qSupported_returns_known_stub_features_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.qSupported_returns_known_stub_features()

    def written_M_content_reads_back_correctly(self):
        TEST_MESSAGE = "Hello, memory"

        # Start up the stub and start/prep the inferior.
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=[
                "set-message:xxxxxxxxxxxxxX",
                "get-data-address-hex:g_message",
                "sleep:1",
                "print-message:"])
        self.test_sequence.add_log_lines(
            [
                # Start running after initial stop.
                "read packet: $c#63",
                # Match output line that prints the memory address of the message buffer within the inferior.
                # Note we require launch-only testing so we can get inferior otuput.
                {"type": "output_match", "regex": self.maybe_strict_output_regex(r"data address: 0x([0-9a-fA-F]+)\r\n"),
                 "capture": {1: "message_address"}},
                # Now stop the inferior.
                "read packet: {}".format(chr(3)),
                # And wait for the stop notification.
                {"direction": "send", "regex": r"^\$T([0-9a-fA-F]{2})thread:([0-9a-fA-F]+);", "capture": {1: "stop_signo", 2: "stop_thread_id"}}],
            True)
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Grab the message address.
        self.assertIsNotNone(context.get("message_address"))
        message_address = int(context.get("message_address"), 16)

        # Hex-encode the test message, adding null termination.
        hex_encoded_message = seven.hexlify(TEST_MESSAGE)

        # Write the message to the inferior. Verify that we can read it with the hex-encoded (m)
        # and binary (x) memory read packets.
        self.reset_test_sequence()
        self.test_sequence.add_log_lines(
            ["read packet: $M{0:x},{1:x}:{2}#00".format(message_address, len(TEST_MESSAGE), hex_encoded_message),
             "send packet: $OK#00",
             "read packet: $m{0:x},{1:x}#00".format(message_address, len(TEST_MESSAGE)),
             "send packet: ${0}#00".format(hex_encoded_message),
             "read packet: $x{0:x},{1:x}#00".format(message_address, len(TEST_MESSAGE)),
             "send packet: ${0}#00".format(TEST_MESSAGE),
             "read packet: $m{0:x},4#00".format(message_address),
             "send packet: ${0}#00".format(hex_encoded_message[0:8]),
             "read packet: $x{0:x},4#00".format(message_address),
             "send packet: ${0}#00".format(TEST_MESSAGE[0:4]),
             "read packet: $c#63",
             {"type": "output_match", "regex": r"^message: (.+)\r\n$", "capture": {1: "printed_message"}},
             "send packet: $W00#00",
             ], True)
        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Ensure what we read from inferior memory is what we wrote.
        printed_message = context.get("printed_message")
        self.assertIsNotNone(printed_message)
        self.assertEqual(printed_message, TEST_MESSAGE + "X")

    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_written_M_content_reads_back_correctly_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.written_M_content_reads_back_correctly()

    @skipIfWindows # No pty support to test any inferior output
    @llgs_test
    @expectedFlakeyLinux("llvm.org/pr25652")
    def test_written_M_content_reads_back_correctly_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.written_M_content_reads_back_correctly()

    def P_writes_all_gpr_registers(self):
        # Start inferior debug session, grab all register info.
        procs = self.prep_debug_monitor_and_inferior(inferior_args=["sleep:2"])
        self.add_register_info_collection_packets()
        self.add_process_info_collection_packets()

        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        # Process register infos.
        reg_infos = self.parse_register_info_packets(context)
        self.assertIsNotNone(reg_infos)
        self.add_lldb_register_index(reg_infos)

        # Process endian.
        process_info = self.parse_process_info_response(context)
        endian = process_info.get("endian")
        self.assertIsNotNone(endian)

        # Pull out the register infos that we think we can bit flip
        # successfully,.
        gpr_reg_infos = [
            reg_info for reg_info in reg_infos if self.is_bit_flippable_register(reg_info)]
        self.assertTrue(len(gpr_reg_infos) > 0)

        # Write flipped bit pattern of existing value to each register.
        (successful_writes, failed_writes) = self.flip_all_bits_in_each_register_value(
            gpr_reg_infos, endian)
        self.trace("successful writes: {}, failed writes: {}".format(successful_writes, failed_writes))
        self.assertTrue(successful_writes > 0)

    # Note: as of this moment, a hefty number of the GPR writes are failing with E32 (everything except rax-rdx, rdi, rsi, rbp).
    # Come back to this.  I have the test rigged to verify that at least some
    # of the bit-flip writes work.
    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_P_writes_all_gpr_registers_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.P_writes_all_gpr_registers()

    @llgs_test
    def test_P_writes_all_gpr_registers_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.P_writes_all_gpr_registers()

    def P_and_p_thread_suffix_work(self):
        # Startup the inferior with three threads.
        procs = self.prep_debug_monitor_and_inferior(
            inferior_args=["thread:new", "thread:new"])
        self.add_thread_suffix_request_packets()
        self.add_register_info_collection_packets()
        self.add_process_info_collection_packets()

        context = self.expect_gdbremote_sequence()
        self.assertIsNotNone(context)

        process_info = self.parse_process_info_response(context)
        self.assertIsNotNone(process_info)
        endian = process_info.get("endian")
        self.assertIsNotNone(endian)

        reg_infos = self.parse_register_info_packets(context)
        self.assertIsNotNone(reg_infos)
        self.add_lldb_register_index(reg_infos)

        reg_index = self.select_modifiable_register(reg_infos)
        self.assertIsNotNone(reg_index)
        reg_byte_size = int(reg_infos[reg_index]["bitsize"]) // 8
        self.assertTrue(reg_byte_size > 0)

        # Run the process a bit so threads can start up, and collect register
        # info.
        context = self.run_process_then_stop(run_seconds=1)
        self.assertIsNotNone(context)

        # Wait for 3 threads to be present.
        threads = self.wait_for_thread_count(3)
        self.assertEqual(len(threads), 3)

        expected_reg_values = []
        register_increment = 1
        next_value = None

        # Set the same register in each of 3 threads to a different value.
        # Verify each one has the unique value.
        for thread in threads:
            # If we don't have a next value yet, start it with the initial read
            # value + 1
            if not next_value:
                # Read pre-existing register value.
                self.reset_test_sequence()
                self.test_sequence.add_log_lines(
                    ["read packet: $p{0:x};thread:{1:x}#00".format(reg_index, thread),
                     {"direction": "send", "regex": r"^\$([0-9a-fA-F]+)#", "capture": {1: "p_response"}},
                     ], True)
                context = self.expect_gdbremote_sequence()
                self.assertIsNotNone(context)

                # Set the next value to use for writing as the increment plus
                # current value.
                p_response = context.get("p_response")
                self.assertIsNotNone(p_response)
                next_value = lldbgdbserverutils.unpack_register_hex_unsigned(
                    endian, p_response)

            # Set new value using P and thread suffix.
            self.reset_test_sequence()
            self.test_sequence.add_log_lines(
                [
                    "read packet: $P{0:x}={1};thread:{2:x}#00".format(
                        reg_index,
                        lldbgdbserverutils.pack_register_hex(
                            endian,
                            next_value,
                            byte_size=reg_byte_size),
                        thread),
                    "send packet: $OK#00",
                ],
                True)
            context = self.expect_gdbremote_sequence()
            self.assertIsNotNone(context)

            # Save the value we set.
            expected_reg_values.append(next_value)

            # Increment value for next thread to use (we want them all
            # different so we can verify they wrote to each thread correctly
            # next.)
            next_value += register_increment

        # Revisit each thread and verify they have the expected value set for
        # the register we wrote.
        thread_index = 0
        for thread in threads:
            # Read pre-existing register value.
            self.reset_test_sequence()
            self.test_sequence.add_log_lines(
                ["read packet: $p{0:x};thread:{1:x}#00".format(reg_index, thread),
                 {"direction": "send", "regex": r"^\$([0-9a-fA-F]+)#", "capture": {1: "p_response"}},
                 ], True)
            context = self.expect_gdbremote_sequence()
            self.assertIsNotNone(context)

            # Get the register value.
            p_response = context.get("p_response")
            self.assertIsNotNone(p_response)
            read_value = lldbgdbserverutils.unpack_register_hex_unsigned(
                endian, p_response)

            # Make sure we read back what we wrote.
            self.assertEqual(read_value, expected_reg_values[thread_index])
            thread_index += 1

    # Note: as of this moment, a hefty number of the GPR writes are failing
    # with E32 (everything except rax-rdx, rdi, rsi, rbp).
    @debugserver_test
    @skipIfDarwinEmbedded # <rdar://problem/34539270> lldb-server tests not updated to work on ios etc yet
    def test_P_and_p_thread_suffix_work_debugserver(self):
        self.init_debugserver_test()
        self.build()
        self.set_inferior_startup_launch()
        self.P_and_p_thread_suffix_work()

    @skipIfWindows
    @llgs_test
    def test_P_and_p_thread_suffix_work_llgs(self):
        self.init_llgs_test()
        self.build()
        self.set_inferior_startup_launch()
        self.P_and_p_thread_suffix_work()