third_party/llvm-project/lldb/source/Host/common/NativeProcessProtocol.cpp - cobalt - Git at Google

 //===-- NativeProcessProtocol.cpp -------------------------------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//

 #include "lldb/Host/common/NativeProcessProtocol.h"
 #include "lldb/Core/State.h"
 #include "lldb/Host/Host.h"
 #include "lldb/Host/common/NativeRegisterContext.h"
 #include "lldb/Host/common/NativeThreadProtocol.h"
 #include "lldb/Host/common/SoftwareBreakpoint.h"
 #include "lldb/Utility/LLDBAssert.h"
 #include "lldb/Utility/Log.h"
 #include "lldb/lldb-enumerations.h"

 using namespace lldb;
 using namespace lldb_private;

 // -----------------------------------------------------------------------------
 // NativeProcessProtocol Members
 // -----------------------------------------------------------------------------

 NativeProcessProtocol::NativeProcessProtocol(lldb::pid_t pid, int terminal_fd,
                                              NativeDelegate &delegate)
     : m_pid(pid), m_terminal_fd(terminal_fd) {
   bool registered = RegisterNativeDelegate(delegate);
   assert(registered);
   (void)registered;
 }

 lldb_private::Status NativeProcessProtocol::Interrupt() {
   Status error;
 #if !defined(SIGSTOP)
   error.SetErrorString("local host does not support signaling");
   return error;
 #else
   return Signal(SIGSTOP);
 #endif
 }

 Status NativeProcessProtocol::IgnoreSignals(llvm::ArrayRef<int> signals) {
   m_signals_to_ignore.clear();
   m_signals_to_ignore.insert(signals.begin(), signals.end());
   return Status();
 }

 lldb_private::Status
 NativeProcessProtocol::GetMemoryRegionInfo(lldb::addr_t load_addr,
                                            MemoryRegionInfo &range_info) {
   // Default: not implemented.
   return Status("not implemented");
 }

 llvm::Optional<WaitStatus> NativeProcessProtocol::GetExitStatus() {
   if (m_state == lldb::eStateExited)
     return m_exit_status;

   return llvm::None;
 }

 bool NativeProcessProtocol::SetExitStatus(WaitStatus status,
                                           bool bNotifyStateChange) {
   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
   LLDB_LOG(log, "status = {0}, notify = {1}", status, bNotifyStateChange);

   // Exit status already set
   if (m_state == lldb::eStateExited) {
     if (m_exit_status)
       LLDB_LOG(log, "exit status already set to {0}", *m_exit_status);
     else
       LLDB_LOG(log, "state is exited, but status not set");
     return false;
   }

   m_state = lldb::eStateExited;
   m_exit_status = status;

   if (bNotifyStateChange)
     SynchronouslyNotifyProcessStateChanged(lldb::eStateExited);

   return true;
 }

 NativeThreadProtocol *NativeProcessProtocol::GetThreadAtIndex(uint32_t idx) {
   std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
   if (idx < m_threads.size())
     return m_threads[idx].get();
   return nullptr;
 }

 NativeThreadProtocol *
 NativeProcessProtocol::GetThreadByIDUnlocked(lldb::tid_t tid) {
   for (const auto &thread : m_threads) {
     if (thread->GetID() == tid)
       return thread.get();
   }
   return nullptr;
 }

 NativeThreadProtocol *NativeProcessProtocol::GetThreadByID(lldb::tid_t tid) {
   std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
   return GetThreadByIDUnlocked(tid);
 }

 bool NativeProcessProtocol::IsAlive() const {
   return m_state != eStateDetached && m_state != eStateExited &&
          m_state != eStateInvalid && m_state != eStateUnloaded;
 }

 const NativeWatchpointList::WatchpointMap &
 NativeProcessProtocol::GetWatchpointMap() const {
   return m_watchpoint_list.GetWatchpointMap();
 }

 llvm::Optional<std::pair<uint32_t, uint32_t>>
 NativeProcessProtocol::GetHardwareDebugSupportInfo() const {
   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));

   // get any thread
   NativeThreadProtocol *thread(
       const_cast<NativeProcessProtocol *>(this)->GetThreadAtIndex(0));
   if (!thread) {
     LLDB_LOG(log, "failed to find a thread to grab a NativeRegisterContext!");
     return llvm::None;
   }

   NativeRegisterContext &reg_ctx = thread->GetRegisterContext();
   return std::make_pair(reg_ctx.NumSupportedHardwareBreakpoints(),
                         reg_ctx.NumSupportedHardwareWatchpoints());
 }

 Status NativeProcessProtocol::SetWatchpoint(lldb::addr_t addr, size_t size,
                                             uint32_t watch_flags,
                                             bool hardware) {
   // This default implementation assumes setting the watchpoint for the process
   // will require setting the watchpoint for each of the threads.  Furthermore,
   // it will track watchpoints set for the process and will add them to each
   // thread that is attached to via the (FIXME implement) OnThreadAttached ()
   // method.

   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));

   // Update the thread list
   UpdateThreads();

   // Keep track of the threads we successfully set the watchpoint for.  If one
   // of the thread watchpoint setting operations fails, back off and remove the
   // watchpoint for all the threads that were successfully set so we get back
   // to a consistent state.
   std::vector<NativeThreadProtocol *> watchpoint_established_threads;

   // Tell each thread to set a watchpoint.  In the event that hardware
   // watchpoints are requested but the SetWatchpoint fails, try to set a
   // software watchpoint as a fallback.  It's conceivable that if there are
   // more threads than hardware watchpoints available, some of the threads will
   // fail to set hardware watchpoints while software ones may be available.
   std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
   for (const auto &thread : m_threads) {
     assert(thread && "thread list should not have a NULL thread!");

     Status thread_error =
         thread->SetWatchpoint(addr, size, watch_flags, hardware);
     if (thread_error.Fail() && hardware) {
       // Try software watchpoints since we failed on hardware watchpoint
       // setting and we may have just run out of hardware watchpoints.
       thread_error = thread->SetWatchpoint(addr, size, watch_flags, false);
       if (thread_error.Success())
         LLDB_LOG(log,
                  "hardware watchpoint requested but software watchpoint set");
     }

     if (thread_error.Success()) {
       // Remember that we set this watchpoint successfully in case we need to
       // clear it later.
       watchpoint_established_threads.push_back(thread.get());
     } else {
       // Unset the watchpoint for each thread we successfully set so that we
       // get back to a consistent state of "not set" for the watchpoint.
       for (auto unwatch_thread_sp : watchpoint_established_threads) {
         Status remove_error = unwatch_thread_sp->RemoveWatchpoint(addr);
         if (remove_error.Fail())
           LLDB_LOG(log, "RemoveWatchpoint failed for pid={0}, tid={1}: {2}",
                    GetID(), unwatch_thread_sp->GetID(), remove_error);
       }

       return thread_error;
     }
   }
   return m_watchpoint_list.Add(addr, size, watch_flags, hardware);
 }

 Status NativeProcessProtocol::RemoveWatchpoint(lldb::addr_t addr) {
   // Update the thread list
   UpdateThreads();

   Status overall_error;

   std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
   for (const auto &thread : m_threads) {
     assert(thread && "thread list should not have a NULL thread!");

     const Status thread_error = thread->RemoveWatchpoint(addr);
     if (thread_error.Fail()) {
       // Keep track of the first thread error if any threads fail. We want to
       // try to remove the watchpoint from every thread, though, even if one or
       // more have errors.
       if (!overall_error.Fail())
         overall_error = thread_error;
     }
   }
   const Status error = m_watchpoint_list.Remove(addr);
   return overall_error.Fail() ? overall_error : error;
 }

 const HardwareBreakpointMap &
 NativeProcessProtocol::GetHardwareBreakpointMap() const {
   return m_hw_breakpoints_map;
 }

 Status NativeProcessProtocol::SetHardwareBreakpoint(lldb::addr_t addr,
                                                     size_t size) {
   // This default implementation assumes setting a hardware breakpoint for this
   // process will require setting same hardware breakpoint for each of its
   // existing threads. New thread will do the same once created.
   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));

   // Update the thread list
   UpdateThreads();

   // Exit here if target does not have required hardware breakpoint capability.
   auto hw_debug_cap = GetHardwareDebugSupportInfo();

   if (hw_debug_cap == llvm::None || hw_debug_cap->first == 0 ||
       hw_debug_cap->first <= m_hw_breakpoints_map.size())
     return Status("Target does not have required no of hardware breakpoints");

   // Vector below stores all thread pointer for which we have we successfully
   // set this hardware breakpoint. If any of the current process threads fails
   // to set this hardware breakpoint then roll back and remove this breakpoint
   // for all the threads that had already set it successfully.
   std::vector<NativeThreadProtocol *> breakpoint_established_threads;

   // Request to set a hardware breakpoint for each of current process threads.
   std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
   for (const auto &thread : m_threads) {
     assert(thread && "thread list should not have a NULL thread!");

     Status thread_error = thread->SetHardwareBreakpoint(addr, size);
     if (thread_error.Success()) {
       // Remember that we set this breakpoint successfully in case we need to
       // clear it later.
       breakpoint_established_threads.push_back(thread.get());
     } else {
       // Unset the breakpoint for each thread we successfully set so that we
       // get back to a consistent state of "not set" for this hardware
       // breakpoint.
       for (auto rollback_thread_sp : breakpoint_established_threads) {
         Status remove_error =
             rollback_thread_sp->RemoveHardwareBreakpoint(addr);
         if (remove_error.Fail())
           LLDB_LOG(log,
                    "RemoveHardwareBreakpoint failed for pid={0}, tid={1}: {2}",
                    GetID(), rollback_thread_sp->GetID(), remove_error);
       }

       return thread_error;
     }
   }

   // Register new hardware breakpoint into hardware breakpoints map of current
   // process.
   m_hw_breakpoints_map[addr] = {addr, size};

   return Status();
 }

 Status NativeProcessProtocol::RemoveHardwareBreakpoint(lldb::addr_t addr) {
   // Update the thread list
   UpdateThreads();

   Status error;

   std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
   for (const auto &thread : m_threads) {
     assert(thread && "thread list should not have a NULL thread!");
     error = thread->RemoveHardwareBreakpoint(addr);
   }

   // Also remove from hardware breakpoint map of current process.
   m_hw_breakpoints_map.erase(addr);

   return error;
 }

 bool NativeProcessProtocol::RegisterNativeDelegate(
     NativeDelegate &native_delegate) {
   std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
   if (std::find(m_delegates.begin(), m_delegates.end(), &native_delegate) !=
       m_delegates.end())
     return false;

   m_delegates.push_back(&native_delegate);
   native_delegate.InitializeDelegate(this);
   return true;
 }

 bool NativeProcessProtocol::UnregisterNativeDelegate(
     NativeDelegate &native_delegate) {
   std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);

   const auto initial_size = m_delegates.size();
   m_delegates.erase(
       remove(m_delegates.begin(), m_delegates.end(), &native_delegate),
       m_delegates.end());

   // We removed the delegate if the count of delegates shrank after removing
   // all copies of the given native_delegate from the vector.
   return m_delegates.size() < initial_size;
 }

 void NativeProcessProtocol::SynchronouslyNotifyProcessStateChanged(
     lldb::StateType state) {
   Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));

   std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
   for (auto native_delegate : m_delegates)
     native_delegate->ProcessStateChanged(this, state);

   if (log) {
     if (!m_delegates.empty()) {
       log->Printf("NativeProcessProtocol::%s: sent state notification [%s] "
                   "from process %" PRIu64,
                   __FUNCTION__, lldb_private::StateAsCString(state), GetID());
     } else {
       log->Printf("NativeProcessProtocol::%s: would send state notification "
                   "[%s] from process %" PRIu64 ", but no delegates",
                   __FUNCTION__, lldb_private::StateAsCString(state), GetID());
     }
   }
 }

 void NativeProcessProtocol::NotifyDidExec() {
   Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
   if (log)
     log->Printf("NativeProcessProtocol::%s - preparing to call delegates",
                 __FUNCTION__);

   {
     std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
     for (auto native_delegate : m_delegates)
       native_delegate->DidExec(this);
   }
 }

 Status NativeProcessProtocol::SetSoftwareBreakpoint(lldb::addr_t addr,
                                                     uint32_t size_hint) {
   Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_BREAKPOINTS));
   if (log)
     log->Printf("NativeProcessProtocol::%s addr = 0x%" PRIx64, __FUNCTION__,
                 addr);

   return m_breakpoint_list.AddRef(
       addr, size_hint, false,
       [this](lldb::addr_t addr, size_t size_hint, bool /* hardware */,
              NativeBreakpointSP &breakpoint_sp) -> Status {
         return SoftwareBreakpoint::CreateSoftwareBreakpoint(
             *this, addr, size_hint, breakpoint_sp);
       });
 }

 Status NativeProcessProtocol::RemoveBreakpoint(lldb::addr_t addr,
                                                bool hardware) {
   if (hardware)
     return RemoveHardwareBreakpoint(addr);
   else
     return m_breakpoint_list.DecRef(addr);
 }

 Status NativeProcessProtocol::EnableBreakpoint(lldb::addr_t addr) {
   return m_breakpoint_list.EnableBreakpoint(addr);
 }

 Status NativeProcessProtocol::DisableBreakpoint(lldb::addr_t addr) {
   return m_breakpoint_list.DisableBreakpoint(addr);
 }

 lldb::StateType NativeProcessProtocol::GetState() const {
   std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
   return m_state;
 }

 void NativeProcessProtocol::SetState(lldb::StateType state,
                                      bool notify_delegates) {
   std::lock_guard<std::recursive_mutex> guard(m_state_mutex);

   if (state == m_state)
     return;

   m_state = state;

   if (StateIsStoppedState(state, false)) {
     ++m_stop_id;

     // Give process a chance to do any stop id bump processing, such as
     // clearing cached data that is invalidated each time the process runs.
     // Note if/when we support some threads running, we'll end up needing to
     // manage this per thread and per process.
     DoStopIDBumped(m_stop_id);
   }

   // Optionally notify delegates of the state change.
   if (notify_delegates)
     SynchronouslyNotifyProcessStateChanged(state);
 }

 uint32_t NativeProcessProtocol::GetStopID() const {
   std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
   return m_stop_id;
 }

 void NativeProcessProtocol::DoStopIDBumped(uint32_t /* newBumpId */) {
   // Default implementation does nothing.
 }

 NativeProcessProtocol::Factory::~Factory() = default;
	//===-- NativeProcessProtocol.cpp -------------------------------- C++ --===//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file is distributed under the University of Illinois Open Source
	// License. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//

	#include "lldb/Host/common/NativeProcessProtocol.h"
	#include "lldb/Core/State.h"
	#include "lldb/Host/Host.h"
	#include "lldb/Host/common/NativeRegisterContext.h"
	#include "lldb/Host/common/NativeThreadProtocol.h"
	#include "lldb/Host/common/SoftwareBreakpoint.h"
	#include "lldb/Utility/LLDBAssert.h"
	#include "lldb/Utility/Log.h"
	#include "lldb/lldb-enumerations.h"

	using namespace lldb;
	using namespace lldb_private;

	// -----------------------------------------------------------------------------
	// NativeProcessProtocol Members
	// -----------------------------------------------------------------------------

	NativeProcessProtocol::NativeProcessProtocol(lldb::pid_t pid, int terminal_fd,
	NativeDelegate &delegate)
	: m_pid(pid), m_terminal_fd(terminal_fd) {
	bool registered = RegisterNativeDelegate(delegate);
	assert(registered);
	(void)registered;
	}

	lldb_private::Status NativeProcessProtocol::Interrupt() {
	Status error;
	#if !defined(SIGSTOP)
	error.SetErrorString("local host does not support signaling");
	return error;
	#else
	return Signal(SIGSTOP);
	#endif
	}

	Status NativeProcessProtocol::IgnoreSignals(llvm::ArrayRef<int> signals) {
	m_signals_to_ignore.clear();
	m_signals_to_ignore.insert(signals.begin(), signals.end());
	return Status();
	}

	lldb_private::Status
	NativeProcessProtocol::GetMemoryRegionInfo(lldb::addr_t load_addr,
	MemoryRegionInfo &range_info) {
	// Default: not implemented.
	return Status("not implemented");
	}

	llvm::Optional<WaitStatus> NativeProcessProtocol::GetExitStatus() {
	if (m_state == lldb::eStateExited)
	return m_exit_status;

	return llvm::None;
	}

	bool NativeProcessProtocol::SetExitStatus(WaitStatus status,
	bool bNotifyStateChange) {
	Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
	LLDB_LOG(log, "status = {0}, notify = {1}", status, bNotifyStateChange);

	// Exit status already set
	if (m_state == lldb::eStateExited) {
	if (m_exit_status)
	LLDB_LOG(log, "exit status already set to {0}", *m_exit_status);
	else
	LLDB_LOG(log, "state is exited, but status not set");
	return false;
	}

	m_state = lldb::eStateExited;
	m_exit_status = status;

	if (bNotifyStateChange)
	SynchronouslyNotifyProcessStateChanged(lldb::eStateExited);

	return true;
	}

	NativeThreadProtocol *NativeProcessProtocol::GetThreadAtIndex(uint32_t idx) {
	std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
	if (idx < m_threads.size())
	return m_threads[idx].get();
	return nullptr;
	}

	NativeThreadProtocol *
	NativeProcessProtocol::GetThreadByIDUnlocked(lldb::tid_t tid) {
	for (const auto &thread : m_threads) {
	if (thread->GetID() == tid)
	return thread.get();
	}
	return nullptr;
	}

	NativeThreadProtocol *NativeProcessProtocol::GetThreadByID(lldb::tid_t tid) {
	std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
	return GetThreadByIDUnlocked(tid);
	}

	bool NativeProcessProtocol::IsAlive() const {
	return m_state != eStateDetached && m_state != eStateExited &&
	m_state != eStateInvalid && m_state != eStateUnloaded;
	}

	const NativeWatchpointList::WatchpointMap &
	NativeProcessProtocol::GetWatchpointMap() const {
	return m_watchpoint_list.GetWatchpointMap();
	}

	llvm::Optional<std::pair<uint32_t, uint32_t>>
	NativeProcessProtocol::GetHardwareDebugSupportInfo() const {
	Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));

	// get any thread
	NativeThreadProtocol *thread(
	const_cast<NativeProcessProtocol *>(this)->GetThreadAtIndex(0));
	if (!thread) {
	LLDB_LOG(log, "failed to find a thread to grab a NativeRegisterContext!");
	return llvm::None;
	}

	NativeRegisterContext &reg_ctx = thread->GetRegisterContext();
	return std::make_pair(reg_ctx.NumSupportedHardwareBreakpoints(),
	reg_ctx.NumSupportedHardwareWatchpoints());
	}

	Status NativeProcessProtocol::SetWatchpoint(lldb::addr_t addr, size_t size,
	uint32_t watch_flags,
	bool hardware) {
	// This default implementation assumes setting the watchpoint for the process
	// will require setting the watchpoint for each of the threads. Furthermore,
	// it will track watchpoints set for the process and will add them to each
	// thread that is attached to via the (FIXME implement) OnThreadAttached ()
	// method.

	Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));

	// Update the thread list
	UpdateThreads();

	// Keep track of the threads we successfully set the watchpoint for. If one
	// of the thread watchpoint setting operations fails, back off and remove the
	// watchpoint for all the threads that were successfully set so we get back
	// to a consistent state.
	std::vector<NativeThreadProtocol *> watchpoint_established_threads;

	// Tell each thread to set a watchpoint. In the event that hardware
	// watchpoints are requested but the SetWatchpoint fails, try to set a
	// software watchpoint as a fallback. It's conceivable that if there are
	// more threads than hardware watchpoints available, some of the threads will
	// fail to set hardware watchpoints while software ones may be available.
	std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
	for (const auto &thread : m_threads) {
	assert(thread && "thread list should not have a NULL thread!");

	Status thread_error =
	thread->SetWatchpoint(addr, size, watch_flags, hardware);
	if (thread_error.Fail() && hardware) {
	// Try software watchpoints since we failed on hardware watchpoint
	// setting and we may have just run out of hardware watchpoints.
	thread_error = thread->SetWatchpoint(addr, size, watch_flags, false);
	if (thread_error.Success())
	LLDB_LOG(log,
	"hardware watchpoint requested but software watchpoint set");
	}

	if (thread_error.Success()) {
	// Remember that we set this watchpoint successfully in case we need to
	// clear it later.
	watchpoint_established_threads.push_back(thread.get());
	} else {
	// Unset the watchpoint for each thread we successfully set so that we
	// get back to a consistent state of "not set" for the watchpoint.
	for (auto unwatch_thread_sp : watchpoint_established_threads) {
	Status remove_error = unwatch_thread_sp->RemoveWatchpoint(addr);
	if (remove_error.Fail())
	LLDB_LOG(log, "RemoveWatchpoint failed for pid={0}, tid={1}: {2}",
	GetID(), unwatch_thread_sp->GetID(), remove_error);
	}

	return thread_error;
	}
	}
	return m_watchpoint_list.Add(addr, size, watch_flags, hardware);
	}

	Status NativeProcessProtocol::RemoveWatchpoint(lldb::addr_t addr) {
	// Update the thread list
	UpdateThreads();

	Status overall_error;

	std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
	for (const auto &thread : m_threads) {
	assert(thread && "thread list should not have a NULL thread!");

	const Status thread_error = thread->RemoveWatchpoint(addr);
	if (thread_error.Fail()) {
	// Keep track of the first thread error if any threads fail. We want to
	// try to remove the watchpoint from every thread, though, even if one or
	// more have errors.
	if (!overall_error.Fail())
	overall_error = thread_error;
	}
	}
	const Status error = m_watchpoint_list.Remove(addr);
	return overall_error.Fail() ? overall_error : error;
	}

	const HardwareBreakpointMap &
	NativeProcessProtocol::GetHardwareBreakpointMap() const {
	return m_hw_breakpoints_map;
	}

	Status NativeProcessProtocol::SetHardwareBreakpoint(lldb::addr_t addr,
	size_t size) {
	// This default implementation assumes setting a hardware breakpoint for this
	// process will require setting same hardware breakpoint for each of its
	// existing threads. New thread will do the same once created.
	Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));

	// Update the thread list
	UpdateThreads();

	// Exit here if target does not have required hardware breakpoint capability.
	auto hw_debug_cap = GetHardwareDebugSupportInfo();

	if (hw_debug_cap == llvm::None \|\| hw_debug_cap->first == 0 \|\|
	hw_debug_cap->first <= m_hw_breakpoints_map.size())
	return Status("Target does not have required no of hardware breakpoints");

	// Vector below stores all thread pointer for which we have we successfully
	// set this hardware breakpoint. If any of the current process threads fails
	// to set this hardware breakpoint then roll back and remove this breakpoint
	// for all the threads that had already set it successfully.
	std::vector<NativeThreadProtocol *> breakpoint_established_threads;

	// Request to set a hardware breakpoint for each of current process threads.
	std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
	for (const auto &thread : m_threads) {
	assert(thread && "thread list should not have a NULL thread!");

	Status thread_error = thread->SetHardwareBreakpoint(addr, size);
	if (thread_error.Success()) {
	// Remember that we set this breakpoint successfully in case we need to
	// clear it later.
	breakpoint_established_threads.push_back(thread.get());
	} else {
	// Unset the breakpoint for each thread we successfully set so that we
	// get back to a consistent state of "not set" for this hardware
	// breakpoint.
	for (auto rollback_thread_sp : breakpoint_established_threads) {
	Status remove_error =
	rollback_thread_sp->RemoveHardwareBreakpoint(addr);
	if (remove_error.Fail())
	LLDB_LOG(log,
	"RemoveHardwareBreakpoint failed for pid={0}, tid={1}: {2}",
	GetID(), rollback_thread_sp->GetID(), remove_error);
	}

	return thread_error;
	}
	}

	// Register new hardware breakpoint into hardware breakpoints map of current
	// process.
	m_hw_breakpoints_map[addr] = {addr, size};

	return Status();
	}

	Status NativeProcessProtocol::RemoveHardwareBreakpoint(lldb::addr_t addr) {
	// Update the thread list
	UpdateThreads();

	Status error;

	std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
	for (const auto &thread : m_threads) {
	assert(thread && "thread list should not have a NULL thread!");
	error = thread->RemoveHardwareBreakpoint(addr);
	}

	// Also remove from hardware breakpoint map of current process.
	m_hw_breakpoints_map.erase(addr);

	return error;
	}

	bool NativeProcessProtocol::RegisterNativeDelegate(
	NativeDelegate &native_delegate) {
	std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
	if (std::find(m_delegates.begin(), m_delegates.end(), &native_delegate) !=
	m_delegates.end())
	return false;

	m_delegates.push_back(&native_delegate);
	native_delegate.InitializeDelegate(this);
	return true;
	}

	bool NativeProcessProtocol::UnregisterNativeDelegate(
	NativeDelegate &native_delegate) {
	std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);

	const auto initial_size = m_delegates.size();
	m_delegates.erase(
	remove(m_delegates.begin(), m_delegates.end(), &native_delegate),
	m_delegates.end());

	// We removed the delegate if the count of delegates shrank after removing
	// all copies of the given native_delegate from the vector.
	return m_delegates.size() < initial_size;
	}

	void NativeProcessProtocol::SynchronouslyNotifyProcessStateChanged(
	lldb::StateType state) {
	Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));

	std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
	for (auto native_delegate : m_delegates)
	native_delegate->ProcessStateChanged(this, state);

	if (log) {
	if (!m_delegates.empty()) {
	log->Printf("NativeProcessProtocol::%s: sent state notification [%s] "
	"from process %" PRIu64,
	__FUNCTION__, lldb_private::StateAsCString(state), GetID());
	} else {
	log->Printf("NativeProcessProtocol::%s: would send state notification "
	"[%s] from process %" PRIu64 ", but no delegates",
	__FUNCTION__, lldb_private::StateAsCString(state), GetID());
	}
	}
	}

	void NativeProcessProtocol::NotifyDidExec() {
	Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
	if (log)
	log->Printf("NativeProcessProtocol::%s - preparing to call delegates",
	__FUNCTION__);

	{
	std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
	for (auto native_delegate : m_delegates)
	native_delegate->DidExec(this);
	}
	}

	Status NativeProcessProtocol::SetSoftwareBreakpoint(lldb::addr_t addr,
	uint32_t size_hint) {
	Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_BREAKPOINTS));
	if (log)
	log->Printf("NativeProcessProtocol::%s addr = 0x%" PRIx64, __FUNCTION__,
	addr);

	return m_breakpoint_list.AddRef(
	addr, size_hint, false,
	[this](lldb::addr_t addr, size_t size_hint, bool /* hardware */,
	NativeBreakpointSP &breakpoint_sp) -> Status {
	return SoftwareBreakpoint::CreateSoftwareBreakpoint(
	*this, addr, size_hint, breakpoint_sp);
	});
	}

	Status NativeProcessProtocol::RemoveBreakpoint(lldb::addr_t addr,
	bool hardware) {
	if (hardware)
	return RemoveHardwareBreakpoint(addr);
	else
	return m_breakpoint_list.DecRef(addr);
	}

	Status NativeProcessProtocol::EnableBreakpoint(lldb::addr_t addr) {
	return m_breakpoint_list.EnableBreakpoint(addr);
	}

	Status NativeProcessProtocol::DisableBreakpoint(lldb::addr_t addr) {
	return m_breakpoint_list.DisableBreakpoint(addr);
	}

	lldb::StateType NativeProcessProtocol::GetState() const {
	std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
	return m_state;
	}

	void NativeProcessProtocol::SetState(lldb::StateType state,
	bool notify_delegates) {
	std::lock_guard<std::recursive_mutex> guard(m_state_mutex);

	if (state == m_state)
	return;

	m_state = state;

	if (StateIsStoppedState(state, false)) {
	++m_stop_id;

	// Give process a chance to do any stop id bump processing, such as
	// clearing cached data that is invalidated each time the process runs.
	// Note if/when we support some threads running, we'll end up needing to
	// manage this per thread and per process.
	DoStopIDBumped(m_stop_id);
	}

	// Optionally notify delegates of the state change.
	if (notify_delegates)
	SynchronouslyNotifyProcessStateChanged(state);
	}

	uint32_t NativeProcessProtocol::GetStopID() const {
	std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
	return m_stop_id;
	}

	void NativeProcessProtocol::DoStopIDBumped(uint32_t /* newBumpId */) {
	// Default implementation does nothing.
	}

	NativeProcessProtocol::Factory::~Factory() = default;