text: //===-- ThreadGDBRemote.cpp -------------------------------------*- C++ -*-===//
  //
  //                     The LLVM Compiler Infrastructure
  //
  // This file is distributed under the University of Illinois Open Source
  // License. See LICENSE.TXT for details.
  //
  //===----------------------------------------------------------------------===//
  
  
  #include "ThreadGDBRemote.h"
  
  #include "lldb/Breakpoint/Watchpoint.h"
  #include "lldb/Core/ArchSpec.h"
  #include "lldb/Core/DataExtractor.h"
  #include "lldb/Core/State.h"
  #include "lldb/Core/StreamString.h"
  #include "lldb/Target/Platform.h"
  #include "lldb/Target/Process.h"
  #include "lldb/Target/RegisterContext.h"
  #include "lldb/Target/StopInfo.h"
  #include "lldb/Target/SystemRuntime.h"
  #include "lldb/Target/Target.h"
  #include "lldb/Target/UnixSignals.h"
  #include "lldb/Target/Unwind.h"
  
  #include "ProcessGDBRemote.h"
  #include "ProcessGDBRemoteLog.h"
  #include "Utility/StringExtractorGDBRemote.h"
  
  using namespace lldb;
  using namespace lldb_private;
  using namespace lldb_private::process_gdb_remote;
  
  //----------------------------------------------------------------------
  // Thread Registers
  //----------------------------------------------------------------------
  
  ThreadGDBRemote::ThreadGDBRemote (Process &process, lldb::tid_t tid) :
      Thread(process, tid),
      m_thread_name (),
      m_dispatch_queue_name (),
      m_thread_dispatch_qaddr (LLDB_INVALID_ADDRESS),
      m_queue_kind(eQueueKindUnknown),
      m_queue_serial(0)
  {
      ProcessGDBRemoteLog::LogIf(GDBR_LOG_THREAD, "%p: ThreadGDBRemote::ThreadGDBRemote (pid = %i, tid = 0x%4.4x)",
                                 this, 
                                 process.GetID(),
                                 GetID());
  }
  
  ThreadGDBRemote::~ThreadGDBRemote ()
  {
      ProcessSP process_sp(GetProcess());
      ProcessGDBRemoteLog::LogIf(GDBR_LOG_THREAD, "%p: ThreadGDBRemote::~ThreadGDBRemote (pid = %i, tid = 0x%4.4x)", 
                                 this, 
                                 process_sp ? process_sp->GetID() : LLDB_INVALID_PROCESS_ID, 
                                 GetID());
      DestroyThread();
  }
  
  const char *
  ThreadGDBRemote::GetName ()
  {
      if (m_thread_name.empty())
          return NULL;
      return m_thread_name.c_str();
  }
  
  void
  ThreadGDBRemote::ClearQueueInfo ()
  {
      m_dispatch_queue_name.clear();
      m_queue_kind = eQueueKindUnknown;
      m_queue_serial = 0;
  }
  
  void
  ThreadGDBRemote::SetQueueInfo (std::string &&queue_name, QueueKind queue_kind, uint64_t queue_serial)
  {
      m_dispatch_queue_name = queue_name;
      m_queue_kind = queue_kind;
      m_queue_serial = queue_serial;
  }
  
  
  const char *
  ThreadGDBRemote::GetQueueName ()
  {
      // If our cached queue info is valid, then someone called ThreadGDBRemote::SetQueueInfo(...)
      // with valid information that was gleaned from the stop reply packet. In this case we trust
      // that the info is valid in m_dispatch_queue_name without refetching it
      if (CachedQueueInfoIsValid())
      {
          if (m_dispatch_queue_name.empty())
              return nullptr;
          else
              return m_dispatch_queue_name.c_str();
      }
      // Always re-fetch the dispatch queue name since it can change
  
      if (m_thread_dispatch_qaddr != 0 || m_thread_dispatch_qaddr != LLDB_INVALID_ADDRESS)
      {
          ProcessSP process_sp (GetProcess());
          if (process_sp)
          {
              SystemRuntime *runtime = process_sp->GetSystemRuntime ();
              if (runtime)
                  m_dispatch_queue_name = runtime->GetQueueNameFromThreadQAddress (m_thread_dispatch_qaddr);
              else
                  m_dispatch_queue_name.clear();
  
              if (!m_dispatch_queue_name.empty())
                  return m_dispatch_queue_name.c_str();
          }
      }
      return NULL;
  }
  
  queue_id_t
  ThreadGDBRemote::GetQueueID ()
  {
      // If our cached queue info is valid, then someone called ThreadGDBRemote::SetQueueInfo(...)
      // with valid information that was gleaned from the stop reply packet. In this case we trust
      // that the info is valid in m_dispatch_queue_name without refetching it
      if (CachedQueueInfoIsValid())
          return m_queue_serial;
  
      if (m_thread_dispatch_qaddr != 0 || m_thread_dispatch_qaddr != LLDB_INVALID_ADDRESS)
      {
          ProcessSP process_sp (GetProcess());
          if (process_sp)
          {
              SystemRuntime *runtime = process_sp->GetSystemRuntime ();
              if (runtime)
              {
                  return runtime->GetQueueIDFromThreadQAddress (m_thread_dispatch_qaddr);
              }
          }
      }
      return LLDB_INVALID_QUEUE_ID;
  }
  
  QueueSP
  ThreadGDBRemote::GetQueue ()
  {
      queue_id_t queue_id = GetQueueID();
      QueueSP queue;
      if (queue_id != LLDB_INVALID_QUEUE_ID)
      {
          ProcessSP process_sp (GetProcess());
          if (process_sp)
          {
              queue = process_sp->GetQueueList().FindQueueByID (queue_id);
          }
      }
      return queue;
  }
  
  addr_t
  ThreadGDBRemote::GetQueueLibdispatchQueueAddress ()
  {
      addr_t dispatch_queue_t_addr = LLDB_INVALID_ADDRESS;
      if (m_thread_dispatch_qaddr != 0 || m_thread_dispatch_qaddr != LLDB_INVALID_ADDRESS)
      {
          ProcessSP process_sp (GetProcess());
          if (process_sp)
          {
              SystemRuntime *runtime = process_sp->GetSystemRuntime ();
              if (runtime)
              {
                  dispatch_queue_t_addr = runtime->GetLibdispatchQueueAddressFromThreadQAddress (m_thread_dispatch_qaddr);
              }
          }
      }
      return dispatch_queue_t_addr;
  }
  
  StructuredData::ObjectSP
  ThreadGDBRemote::FetchThreadExtendedInfo ()
  {
      StructuredData::ObjectSP object_sp;
      const lldb::user_id_t tid = GetProtocolID();
      Log *log(GetLogIfAnyCategoriesSet (GDBR_LOG_THREAD));
      if (log)
          log->Printf ("Fetching extended information for thread %4.4" PRIx64, tid);
      ProcessSP process_sp (GetProcess());
      if (process_sp)
      {
          ProcessGDBRemote *gdb_process = static_cast<ProcessGDBRemote *>(process_sp.get());
          object_sp = gdb_process->GetExtendedInfoForThread (tid);
      }
      return object_sp;
  }
  
  void
  ThreadGDBRemote::WillResume (StateType resume_state)
  {
      int signo = GetResumeSignal();
      const lldb::user_id_t tid = GetProtocolID();
      Log *log(GetLogIfAnyCategoriesSet (GDBR_LOG_THREAD));
      if (log)
          log->Printf ("Resuming thread: %4.4" PRIx64 " with state: %s.", tid, StateAsCString(resume_state));
  
      ProcessSP process_sp (GetProcess());
      if (process_sp)
      {
          ProcessGDBRemote *gdb_process = static_cast<ProcessGDBRemote *>(process_sp.get());
          switch (resume_state)
          {
          case eStateSuspended:
          case eStateStopped:
              // Don't append anything for threads that should stay stopped.
              break;
  
          case eStateRunning:
              if (gdb_process->GetUnixSignals()->SignalIsValid(signo))
                  gdb_process->m_continue_C_tids.push_back(std::make_pair(tid, signo));
              else
                  gdb_process->m_continue_c_tids.push_back(tid);
              break;
  
          case eStateStepping:
              if (gdb_process->GetUnixSignals()->SignalIsValid(signo))
                  gdb_process->m_continue_S_tids.push_back(std::make_pair(tid, signo));
              else
                  gdb_process->m_continue_s_tids.push_back(tid);
              break;
  
          default:
              break;
          }
      }
  }
  
  void
  ThreadGDBRemote::RefreshStateAfterStop()
  {
      // Invalidate all registers in our register context. We don't set "force" to
      // true because the stop reply packet might have had some register values
      // that were expedited and these will already be copied into the register
      // context by the time this function gets called. The GDBRemoteRegisterContext
      // class has been made smart enough to detect when it needs to invalidate
      // which registers are valid by putting hooks in the register read and 
      // register supply functions where they check the process stop ID and do
      // the right thing.
      const bool force = false;
      GetRegisterContext()->InvalidateIfNeeded (force);
  }
  
  bool
  ThreadGDBRemote::ThreadIDIsValid (lldb::tid_t thread)
  {
      return thread != 0;
  }
  
  void
  ThreadGDBRemote::Dump(Log *log, uint32_t index)
  {
  }
  
  
  bool
  ThreadGDBRemote::ShouldStop (bool &step_more)
  {
      return true;
  }
  lldb::RegisterContextSP
  ThreadGDBRemote::GetRegisterContext ()
  {
      if (m_reg_context_sp.get() == NULL)
          m_reg_context_sp = CreateRegisterContextForFrame (NULL);
      return m_reg_context_sp;
  }
  
  lldb::RegisterContextSP
  ThreadGDBRemote::CreateRegisterContextForFrame (StackFrame *frame)
  {
      lldb::RegisterContextSP reg_ctx_sp;
      uint32_t concrete_frame_idx = 0;
      
      if (frame)
          concrete_frame_idx = frame->GetConcreteFrameIndex ();
  
      
      if (concrete_frame_idx == 0)
      {
          ProcessSP process_sp (GetProcess());
          if (process_sp)
          {
              ProcessGDBRemote *gdb_process = static_cast<ProcessGDBRemote *>(process_sp.get());
              // read_all_registers_at_once will be true if 'p' packet is not supported.
              bool read_all_registers_at_once = !gdb_process->GetGDBRemote().GetpPacketSupported (GetID());
              reg_ctx_sp.reset (new GDBRemoteRegisterContext (*this, concrete_frame_idx, gdb_process->m_register_info, read_all_registers_at_once));
          }
      }
      else
      {
          Unwind *unwinder = GetUnwinder ();
          if (unwinder)
              reg_ctx_sp = unwinder->CreateRegisterContextForFrame (frame);
      }
      return reg_ctx_sp;
  }
  
  bool
  ThreadGDBRemote::PrivateSetRegisterValue (uint32_t reg, StringExtractor &response)
  {
      GDBRemoteRegisterContext *gdb_reg_ctx = static_cast<GDBRemoteRegisterContext *>(GetRegisterContext ().get());
      assert (gdb_reg_ctx);
      return gdb_reg_ctx->PrivateSetRegisterValue (reg, response);
  }
  
  bool
  ThreadGDBRemote::CalculateStopInfo ()
  {
      ProcessSP process_sp (GetProcess());
      if (process_sp)
          return static_cast<ProcessGDBRemote *>(process_sp.get())->CalculateThreadStopInfo(this);
      return false;
  }
  
  
  