Import LLVM 10.0.0 release including clang, lld and lldb.

ok hackroom
tested by plenty

1 files changed, 285 insertions, 0 deletions

diff --git a/gnu/llvm/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationReplayServer.cpp b/gnu/llvm/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationReplayServer.cpp
new file mode 100644
index 00000000000..15c73e78bd4
--- /dev/null
+++ b/gnu/llvm/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationReplayServer.cpp
@@ -0,0 +1,285 @@
+//===-- GDBRemoteCommunicationReplayServer.cpp ------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <errno.h>
+
+#include "lldb/Host/Config.h"
+#include "llvm/ADT/ScopeExit.h"
+
+#include "GDBRemoteCommunicationReplayServer.h"
+#include "ProcessGDBRemoteLog.h"
+
+// C Includes
+// C++ Includes
+#include <cstring>
+
+// Project includes
+#include "lldb/Host/ThreadLauncher.h"
+#include "lldb/Utility/ConstString.h"
+#include "lldb/Utility/Event.h"
+#include "lldb/Utility/FileSpec.h"
+#include "lldb/Utility/StreamString.h"
+#include "lldb/Utility/StringExtractorGDBRemote.h"
+
+using namespace llvm;
+using namespace lldb;
+using namespace lldb_private;
+using namespace lldb_private::process_gdb_remote;
+
+/// Check if the given expected packet matches the actual packet.
+static bool unexpected(llvm::StringRef expected, llvm::StringRef actual) {
+  // The 'expected' string contains the raw data, including the leading $ and
+  // trailing checksum. The 'actual' string contains only the packet's content.
+  if (expected.contains(actual))
+    return false;
+  // Contains a PID which might be different.
+  if (expected.contains("vAttach"))
+    return false;
+  // Contains a ascii-hex-path.
+  if (expected.contains("QSetSTD"))
+    return false;
+  // Contains environment values.
+  if (expected.contains("QEnvironment"))
+    return false;
+
+  return true;
+}
+
+/// Check if we should reply to the given packet.
+static bool skip(llvm::StringRef data) {
+  assert(!data.empty() && "Empty packet?");
+
+  // We've already acknowledge the '+' packet so we're done here.
+  if (data == "+")
+    return true;
+
+  /// Don't 't reply to ^C. We need this because of stop reply packets, which
+  /// are only returned when the target halts. Reproducers synchronize these
+  /// 'asynchronous' replies, by recording them as a regular replies to the
+  /// previous packet (e.g. vCont). As a result, we should ignore real
+  /// asynchronous requests.
+  if (data.data()[0] == 0x03)
+    return true;
+
+  return false;
+}
+
+GDBRemoteCommunicationReplayServer::GDBRemoteCommunicationReplayServer()
+    : GDBRemoteCommunication("gdb-replay", "gdb-replay.rx_packet"),
+      m_async_broadcaster(nullptr, "lldb.gdb-replay.async-broadcaster"),
+      m_async_listener_sp(
+          Listener::MakeListener("lldb.gdb-replay.async-listener")),
+      m_async_thread_state_mutex(), m_skip_acks(false) {
+  m_async_broadcaster.SetEventName(eBroadcastBitAsyncContinue,
+                                   "async thread continue");
+  m_async_broadcaster.SetEventName(eBroadcastBitAsyncThreadShouldExit,
+                                   "async thread should exit");
+
+  const uint32_t async_event_mask =
+      eBroadcastBitAsyncContinue | eBroadcastBitAsyncThreadShouldExit;
+  m_async_listener_sp->StartListeningForEvents(&m_async_broadcaster,
+                                               async_event_mask);
+}
+
+GDBRemoteCommunicationReplayServer::~GDBRemoteCommunicationReplayServer() {
+  StopAsyncThread();
+}
+
+GDBRemoteCommunication::PacketResult
+GDBRemoteCommunicationReplayServer::GetPacketAndSendResponse(
+    Timeout<std::micro> timeout, Status &error, bool &interrupt, bool &quit) {
+  std::lock_guard<std::recursive_mutex> guard(m_async_thread_state_mutex);
+
+  StringExtractorGDBRemote packet;
+  PacketResult packet_result = WaitForPacketNoLock(packet, timeout, false);
+
+  if (packet_result != PacketResult::Success) {
+    if (!IsConnected()) {
+      error.SetErrorString("lost connection");
+      quit = true;
+    } else {
+      error.SetErrorString("timeout");
+    }
+    return packet_result;
+  }
+
+  m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncContinue);
+
+  // Check if we should reply to this packet.
+  if (skip(packet.GetStringRef()))
+    return PacketResult::Success;
+
+  // This completes the handshake. Since m_send_acks was true, we can unset it
+  // already.
+  if (packet.GetStringRef() == "QStartNoAckMode")
+    m_send_acks = false;
+
+  // A QEnvironment packet is sent for every environment variable. If the
+  // number of environment variables is different during replay, the replies
+  // become out of sync.
+  if (packet.GetStringRef().find("QEnvironment") == 0)
+    return SendRawPacketNoLock("$OK#9a");
+
+  Log *log(ProcessGDBRemoteLog::GetLogIfAllCategoriesSet(GDBR_LOG_PROCESS));
+  while (!m_packet_history.empty()) {
+    // Pop last packet from the history.
+    GDBRemotePacket entry = m_packet_history.back();
+    m_packet_history.pop_back();
+
+    // We've handled the handshake implicitly before. Skip the packet and move
+    // on.
+    if (entry.packet.data == "+")
+      continue;
+
+    if (entry.type == GDBRemotePacket::ePacketTypeSend) {
+      if (unexpected(entry.packet.data, packet.GetStringRef())) {
+        LLDB_LOG(log,
+                 "GDBRemoteCommunicationReplayServer expected packet: '{0}'",
+                 entry.packet.data);
+        LLDB_LOG(log, "GDBRemoteCommunicationReplayServer actual packet: '{0}'",
+                 packet.GetStringRef());
+#ifndef NDEBUG
+        // This behaves like a regular assert, but prints the expected and
+        // received packet before aborting.
+        printf("Reproducer expected packet: '%s'\n", entry.packet.data.c_str());
+        printf("Reproducer received packet: '%s'\n",
+               packet.GetStringRef().data());
+        llvm::report_fatal_error("Encountered unexpected packet during replay");
+#endif
+        return PacketResult::ErrorSendFailed;
+      }
+
+      // Ignore QEnvironment packets as they're handled earlier.
+      if (entry.packet.data.find("QEnvironment") == 1) {
+        assert(m_packet_history.back().type ==
+               GDBRemotePacket::ePacketTypeRecv);
+        m_packet_history.pop_back();
+      }
+
+      continue;
+    }
+
+    if (entry.type == GDBRemotePacket::ePacketTypeInvalid) {
+      LLDB_LOG(
+          log,
+          "GDBRemoteCommunicationReplayServer skipped invalid packet: '{0}'",
+          packet.GetStringRef());
+      continue;
+    }
+
+    LLDB_LOG(log,
+             "GDBRemoteCommunicationReplayServer replied to '{0}' with '{1}'",
+             packet.GetStringRef(), entry.packet.data);
+    return SendRawPacketNoLock(entry.packet.data);
+  }
+
+  quit = true;
+
+  return packet_result;
+}
+
+llvm::Error
+GDBRemoteCommunicationReplayServer::LoadReplayHistory(const FileSpec &path) {
+  auto error_or_file = MemoryBuffer::getFile(path.GetPath());
+  if (auto err = error_or_file.getError())
+    return errorCodeToError(err);
+
+  yaml::Input yin((*error_or_file)->getBuffer());
+  yin >> m_packet_history;
+
+  if (auto err = yin.error())
+    return errorCodeToError(err);
+
+  // We want to manipulate the vector like a stack so we need to reverse the
+  // order of the packets to have the oldest on at the back.
+  std::reverse(m_packet_history.begin(), m_packet_history.end());
+
+  return Error::success();
+}
+
+bool GDBRemoteCommunicationReplayServer::StartAsyncThread() {
+  std::lock_guard<std::recursive_mutex> guard(m_async_thread_state_mutex);
+  if (!m_async_thread.IsJoinable()) {
+    // Create a thread that watches our internal state and controls which
+    // events make it to clients (into the DCProcess event queue).
+    llvm::Expected<HostThread> async_thread = ThreadLauncher::LaunchThread(
+        "<lldb.gdb-replay.async>",
+        GDBRemoteCommunicationReplayServer::AsyncThread, this);
+    if (!async_thread) {
+      LLDB_LOG_ERROR(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST),
+                     async_thread.takeError(),
+                     "failed to launch host thread: {}");
+      return false;
+    }
+    m_async_thread = *async_thread;
+  }
+
+  // Wait for handshake.
+  m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncContinue);
+
+  return m_async_thread.IsJoinable();
+}
+
+void GDBRemoteCommunicationReplayServer::StopAsyncThread() {
+  std::lock_guard<std::recursive_mutex> guard(m_async_thread_state_mutex);
+
+  if (!m_async_thread.IsJoinable())
+    return;
+
+  // Request thread to stop.
+  m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncThreadShouldExit);
+
+  // Disconnect client.
+  Disconnect();
+
+  // Stop the thread.
+  m_async_thread.Join(nullptr);
+  m_async_thread.Reset();
+}
+
+void GDBRemoteCommunicationReplayServer::ReceivePacket(
+    GDBRemoteCommunicationReplayServer &server, bool &done) {
+  Status error;
+  bool interrupt;
+  auto packet_result = server.GetPacketAndSendResponse(std::chrono::seconds(1),
+                                                       error, interrupt, done);
+  if (packet_result != GDBRemoteCommunication::PacketResult::Success &&
+      packet_result !=
+          GDBRemoteCommunication::PacketResult::ErrorReplyTimeout) {
+    done = true;
+  } else {
+    server.m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncContinue);
+  }
+}
+
+thread_result_t GDBRemoteCommunicationReplayServer::AsyncThread(void *arg) {
+  GDBRemoteCommunicationReplayServer *server =
+      (GDBRemoteCommunicationReplayServer *)arg;
+  auto D = make_scope_exit([&]() { server->Disconnect(); });
+  EventSP event_sp;
+  bool done = false;
+  while (!done) {
+    if (server->m_async_listener_sp->GetEvent(event_sp, llvm::None)) {
+      const uint32_t event_type = event_sp->GetType();
+      if (event_sp->BroadcasterIs(&server->m_async_broadcaster)) {
+        switch (event_type) {
+        case eBroadcastBitAsyncContinue:
+          ReceivePacket(*server, done);
+          if (done)
+            return {};
+          break;
+        case eBroadcastBitAsyncThreadShouldExit:
+        default:
+          return {};
+        }
+      }
+    }
+  }
+
+  return {};
+}