llvm-project/lldb/source/Target/StopInfo.cpp

802 lines
28 KiB
C++

//===-- StopInfo.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/Target/StopInfo.h"
// C Includes
// C++ Includes
#include <string>
// Other libraries and framework includes
// Project includes
#include "lldb/Core/Log.h"
#include "lldb/Breakpoint/Breakpoint.h"
#include "lldb/Breakpoint/BreakpointLocation.h"
#include "lldb/Breakpoint/StoppointCallbackContext.h"
#include "lldb/Breakpoint/Watchpoint.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Core/StreamString.h"
#include "lldb/Expression/ClangUserExpression.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
#include "lldb/Target/ThreadPlan.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/UnixSignals.h"
using namespace lldb;
using namespace lldb_private;
StopInfo::StopInfo (Thread &thread, uint64_t value) :
m_thread (thread),
m_stop_id (thread.GetProcess()->GetStopID()),
m_resume_id (thread.GetProcess()->GetResumeID()),
m_value (value)
{
}
bool
StopInfo::IsValid () const
{
return m_thread.GetProcess()->GetStopID() == m_stop_id;
}
void
StopInfo::MakeStopInfoValid ()
{
m_stop_id = m_thread.GetProcess()->GetStopID();
m_resume_id = m_thread.GetProcess()->GetResumeID();
}
bool
StopInfo::HasTargetRunSinceMe ()
{
lldb::StateType ret_type = m_thread.GetProcess()->GetPrivateState();
if (ret_type == eStateRunning)
{
return true;
}
else if (ret_type == eStateStopped)
{
// This is a little tricky. We want to count "run and stopped again before you could
// ask this question as a "TRUE" answer to HasTargetRunSinceMe. But we don't want to
// include any running of the target done for expressions. So we track both resumes,
// and resumes caused by expressions, and check if there are any resumes NOT caused
// by expressions.
uint32_t curr_resume_id = m_thread.GetProcess()->GetResumeID();
uint32_t last_user_expression_id = m_thread.GetProcess()->GetLastUserExpressionResumeID ();
if (curr_resume_id == m_resume_id)
{
return false;
}
else if (curr_resume_id > last_user_expression_id)
{
return true;
}
}
return false;
}
//----------------------------------------------------------------------
// StopInfoBreakpoint
//----------------------------------------------------------------------
namespace lldb_private
{
class StopInfoBreakpoint : public StopInfo
{
public:
StopInfoBreakpoint (Thread &thread, break_id_t break_id) :
StopInfo (thread, break_id),
m_description(),
m_should_stop (false),
m_should_stop_is_valid (false),
m_should_perform_action (true),
m_address (LLDB_INVALID_ADDRESS)
{
BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
if (bp_site_sp)
{
m_address = bp_site_sp->GetLoadAddress();
}
}
StopInfoBreakpoint (Thread &thread, break_id_t break_id, bool should_stop) :
StopInfo (thread, break_id),
m_description(),
m_should_stop (should_stop),
m_should_stop_is_valid (true),
m_should_perform_action (true),
m_address (LLDB_INVALID_ADDRESS)
{
BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
if (bp_site_sp)
{
m_address = bp_site_sp->GetLoadAddress();
}
}
virtual ~StopInfoBreakpoint ()
{
}
virtual StopReason
GetStopReason () const
{
return eStopReasonBreakpoint;
}
virtual bool
ShouldStop (Event *event_ptr)
{
if (!m_should_stop_is_valid)
{
// Only check once if we should stop at a breakpoint
BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
if (bp_site_sp)
{
ExecutionContext exe_ctx (m_thread.GetStackFrameAtIndex(0));
StoppointCallbackContext context (event_ptr, exe_ctx, true);
m_should_stop = bp_site_sp->ShouldStop (&context);
}
else
{
LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
if (log)
log->Printf ("Process::%s could not find breakpoint site id: %lld...", __FUNCTION__, m_value);
m_should_stop = true;
}
m_should_stop_is_valid = true;
}
return m_should_stop;
}
virtual void
PerformAction (Event *event_ptr)
{
if (!m_should_perform_action)
return;
m_should_perform_action = false;
LogSP log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_BREAKPOINTS);
BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
if (bp_site_sp)
{
size_t num_owners = bp_site_sp->GetNumberOfOwners();
if (num_owners == 0)
{
m_should_stop = true;
}
else
{
// We go through each location, and test first its condition. If the condition says to stop,
// then we run the callback for that location. If that callback says to stop as well, then
// we set m_should_stop to true; we are going to stop.
// But we still want to give all the breakpoints whose conditions say we are going to stop a
// chance to run their callbacks.
// Of course if any callback restarts the target by putting "continue" in the callback, then
// we're going to restart, without running the rest of the callbacks. And in this case we will
// end up not stopping even if another location said we should stop. But that's better than not
// running all the callbacks.
m_should_stop = false;
ExecutionContext exe_ctx (m_thread.GetStackFrameAtIndex(0));
StoppointCallbackContext context (event_ptr, exe_ctx, false);
for (size_t j = 0; j < num_owners; j++)
{
lldb::BreakpointLocationSP bp_loc_sp = bp_site_sp->GetOwnerAtIndex(j);
// First run the condition for the breakpoint. If that says we should stop, then we'll run
// the callback for the breakpoint. If the callback says we shouldn't stop that will win.
bool condition_says_stop = true;
if (bp_loc_sp->GetConditionText() != NULL)
{
// We need to make sure the user sees any parse errors in their condition, so we'll hook the
// constructor errors up to the debugger's Async I/O.
ValueObjectSP result_valobj_sp;
ExecutionResults result_code;
ValueObjectSP result_value_sp;
const bool discard_on_error = true;
Error error;
result_code = ClangUserExpression::EvaluateWithError (exe_ctx,
eExecutionPolicyAlways,
lldb::eLanguageTypeUnknown,
ClangUserExpression::eResultTypeAny,
discard_on_error,
bp_loc_sp->GetConditionText(),
NULL,
result_value_sp,
error);
if (result_code == eExecutionCompleted)
{
if (result_value_sp)
{
Scalar scalar_value;
if (result_value_sp->ResolveValue (scalar_value))
{
if (scalar_value.ULongLong(1) == 0)
condition_says_stop = false;
else
condition_says_stop = true;
if (log)
log->Printf("Condition successfully evaluated, result is %s.\n",
m_should_stop ? "true" : "false");
}
else
{
condition_says_stop = true;
if (log)
log->Printf("Failed to get an integer result from the expression.");
}
}
}
else
{
Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger();
StreamSP error_sp = debugger.GetAsyncErrorStream ();
error_sp->Printf ("Stopped due to an error evaluating condition of breakpoint ");
bp_loc_sp->GetDescription (error_sp.get(), eDescriptionLevelBrief);
error_sp->Printf (": \"%s\"",
bp_loc_sp->GetConditionText());
error_sp->EOL();
const char *err_str = error.AsCString("<Unknown Error>");
if (log)
log->Printf("Error evaluating condition: \"%s\"\n", err_str);
error_sp->PutCString (err_str);
error_sp->EOL();
error_sp->Flush();
// If the condition fails to be parsed or run, we should stop.
condition_says_stop = true;
}
}
// If this location's condition says we should aren't going to stop,
// then don't run the callback for this location.
if (!condition_says_stop)
continue;
bool callback_says_stop;
// FIXME: For now the callbacks have to run in async mode - the first time we restart we need
// to get out of there. So set it here.
// When we figure out how to nest breakpoint hits then this will change.
Debugger &debugger = m_thread.CalculateTarget()->GetDebugger();
bool old_async = debugger.GetAsyncExecution();
debugger.SetAsyncExecution (true);
callback_says_stop = bp_loc_sp->InvokeCallback (&context);
debugger.SetAsyncExecution (old_async);
if (callback_says_stop)
m_should_stop = true;
// Also make sure that the callback hasn't continued the target.
// If it did, when we'll set m_should_start to false and get out of here.
if (HasTargetRunSinceMe ())
{
m_should_stop = false;
break;
}
}
}
// We've figured out what this stop wants to do, so mark it as valid so we don't compute it again.
m_should_stop_is_valid = true;
}
else
{
m_should_stop = true;
m_should_stop_is_valid = true;
LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
if (log)
log->Printf ("Process::%s could not find breakpoint site id: %lld...", __FUNCTION__, m_value);
}
if (log)
log->Printf ("Process::%s returning from action with m_should_stop: %d.", __FUNCTION__, m_should_stop);
}
virtual bool
ShouldNotify (Event *event_ptr)
{
BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
if (bp_site_sp)
{
bool all_internal = true;
for (uint32_t i = 0; i < bp_site_sp->GetNumberOfOwners(); i++)
{
if (!bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint().IsInternal())
{
all_internal = false;
break;
}
}
return all_internal == false;
}
return true;
}
virtual const char *
GetDescription ()
{
if (m_description.empty())
{
BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
if (bp_site_sp)
{
StreamString strm;
strm.Printf("breakpoint ");
bp_site_sp->GetDescription(&strm, eDescriptionLevelBrief);
m_description.swap (strm.GetString());
}
else
{
StreamString strm;
if (m_address == LLDB_INVALID_ADDRESS)
strm.Printf("breakpoint site %lli which has been deleted - unknown address", m_value);
else
strm.Printf("breakpoint site %lli which has been deleted - was at 0x%llx", m_value, m_address);
m_description.swap (strm.GetString());
}
}
return m_description.c_str();
}
private:
std::string m_description;
bool m_should_stop;
bool m_should_stop_is_valid;
bool m_should_perform_action; // Since we are trying to preserve the "state" of the system even if we run functions
// etc. behind the users backs, we need to make sure we only REALLY perform the action once.
lldb::addr_t m_address; // We use this to capture the breakpoint site address when we create the StopInfo,
// in case somebody deletes it between the time the StopInfo is made and the
// description is asked for.
};
//----------------------------------------------------------------------
// StopInfoWatchpoint
//----------------------------------------------------------------------
class StopInfoWatchpoint : public StopInfo
{
public:
StopInfoWatchpoint (Thread &thread, break_id_t watch_id) :
StopInfo(thread, watch_id),
m_description(),
m_should_stop(false),
m_should_stop_is_valid(false)
{
}
virtual ~StopInfoWatchpoint ()
{
}
virtual StopReason
GetStopReason () const
{
return eStopReasonWatchpoint;
}
virtual bool
ShouldStop (Event *event_ptr)
{
// ShouldStop() method is idempotent and should not affect hit count.
// See Process::RunPrivateStateThread()->Process()->HandlePrivateEvent()
// -->Process()::ShouldBroadcastEvent()->ThreadList::ShouldStop()->
// Thread::ShouldStop()->ThreadPlanBase::ShouldStop()->
// StopInfoWatchpoint::ShouldStop() and
// Event::DoOnRemoval()->Process::ProcessEventData::DoOnRemoval()->
// StopInfoWatchpoint::PerformAction().
if (m_should_stop_is_valid)
return m_should_stop;
WatchpointSP wp_sp =
m_thread.CalculateTarget()->GetWatchpointList().FindByID(GetValue());
if (wp_sp)
{
// Check if we should stop at a watchpoint.
ExecutionContext exe_ctx (m_thread.GetStackFrameAtIndex(0));
StoppointCallbackContext context (event_ptr, exe_ctx, true);
m_should_stop = wp_sp->ShouldStop (&context);
}
else
{
LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
if (log)
log->Printf ("Process::%s could not find watchpoint location id: %lld...",
__FUNCTION__, GetValue());
m_should_stop = true;
}
m_should_stop_is_valid = true;
return m_should_stop;
}
// Perform any action that is associated with this stop. This is done as the
// Event is removed from the event queue.
virtual void
PerformAction (Event *event_ptr)
{
LogSP log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_BREAKPOINTS);
// We're going to calculate if we should stop or not in some way during the course of
// this code. Also by default we're going to stop, so set that here.
m_should_stop = true;
WatchpointSP wp_sp =
m_thread.CalculateTarget()->GetWatchpointList().FindByID(GetValue());
if (wp_sp)
{
ExecutionContext exe_ctx (m_thread.GetStackFrameAtIndex(0));
StoppointCallbackContext context (event_ptr, exe_ctx, false);
bool stop_requested = wp_sp->InvokeCallback (&context);
// Also make sure that the callback hasn't continued the target.
// If it did, when we'll set m_should_start to false and get out of here.
if (HasTargetRunSinceMe ())
m_should_stop = false;
if (m_should_stop && !stop_requested)
{
// We have been vetoed.
m_should_stop = false;
}
if (m_should_stop && wp_sp->GetConditionText() != NULL)
{
// We need to make sure the user sees any parse errors in their condition, so we'll hook the
// constructor errors up to the debugger's Async I/O.
ExecutionResults result_code;
ValueObjectSP result_value_sp;
const bool discard_on_error = true;
Error error;
result_code = ClangUserExpression::EvaluateWithError (exe_ctx,
eExecutionPolicyAlways,
lldb::eLanguageTypeUnknown,
ClangUserExpression::eResultTypeAny,
discard_on_error,
wp_sp->GetConditionText(),
NULL,
result_value_sp,
error);
if (result_code == eExecutionCompleted)
{
if (result_value_sp)
{
Scalar scalar_value;
if (result_value_sp->ResolveValue (scalar_value))
{
if (scalar_value.ULongLong(1) == 0)
{
// We have been vetoed. This takes precedence over querying
// the watchpoint whether it should stop (aka ignore count and
// friends). See also StopInfoWatchpoint::ShouldStop() as well
// as Process::ProcessEventData::DoOnRemoval().
m_should_stop = false;
}
else
m_should_stop = true;
if (log)
log->Printf("Condition successfully evaluated, result is %s.\n",
m_should_stop ? "true" : "false");
}
else
{
m_should_stop = true;
if (log)
log->Printf("Failed to get an integer result from the expression.");
}
}
}
else
{
Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger();
StreamSP error_sp = debugger.GetAsyncErrorStream ();
error_sp->Printf ("Stopped due to an error evaluating condition of watchpoint ");
wp_sp->GetDescription (error_sp.get(), eDescriptionLevelBrief);
error_sp->Printf (": \"%s\"",
wp_sp->GetConditionText());
error_sp->EOL();
const char *err_str = error.AsCString("<Unknown Error>");
if (log)
log->Printf("Error evaluating condition: \"%s\"\n", err_str);
error_sp->PutCString (err_str);
error_sp->EOL();
error_sp->Flush();
// If the condition fails to be parsed or run, we should stop.
m_should_stop = true;
}
}
}
else
{
LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
if (log)
log->Printf ("Process::%s could not find watchpoint id: %lld...", __FUNCTION__, m_value);
}
if (log)
log->Printf ("Process::%s returning from action with m_should_stop: %d.", __FUNCTION__, m_should_stop);
}
virtual const char *
GetDescription ()
{
if (m_description.empty())
{
StreamString strm;
strm.Printf("watchpoint %lli", m_value);
m_description.swap (strm.GetString());
}
return m_description.c_str();
}
private:
std::string m_description;
bool m_should_stop;
bool m_should_stop_is_valid;
};
//----------------------------------------------------------------------
// StopInfoUnixSignal
//----------------------------------------------------------------------
class StopInfoUnixSignal : public StopInfo
{
public:
StopInfoUnixSignal (Thread &thread, int signo) :
StopInfo (thread, signo)
{
}
virtual ~StopInfoUnixSignal ()
{
}
virtual StopReason
GetStopReason () const
{
return eStopReasonSignal;
}
virtual bool
ShouldStop (Event *event_ptr)
{
return m_thread.GetProcess()->GetUnixSignals().GetShouldStop (m_value);
}
// If should stop returns false, check if we should notify of this event
virtual bool
ShouldNotify (Event *event_ptr)
{
return m_thread.GetProcess()->GetUnixSignals().GetShouldNotify (m_value);
}
virtual void
WillResume (lldb::StateType resume_state)
{
if (m_thread.GetProcess()->GetUnixSignals().GetShouldSuppress(m_value) == false)
m_thread.SetResumeSignal(m_value);
}
virtual const char *
GetDescription ()
{
if (m_description.empty())
{
StreamString strm;
const char *signal_name = m_thread.GetProcess()->GetUnixSignals().GetSignalAsCString (m_value);
if (signal_name)
strm.Printf("signal %s", signal_name);
else
strm.Printf("signal %lli", m_value);
m_description.swap (strm.GetString());
}
return m_description.c_str();
}
};
//----------------------------------------------------------------------
// StopInfoTrace
//----------------------------------------------------------------------
class StopInfoTrace : public StopInfo
{
public:
StopInfoTrace (Thread &thread) :
StopInfo (thread, LLDB_INVALID_UID)
{
}
virtual ~StopInfoTrace ()
{
}
virtual StopReason
GetStopReason () const
{
return eStopReasonTrace;
}
virtual const char *
GetDescription ()
{
if (m_description.empty())
return "trace";
else
return m_description.c_str();
}
};
//----------------------------------------------------------------------
// StopInfoException
//----------------------------------------------------------------------
class StopInfoException : public StopInfo
{
public:
StopInfoException (Thread &thread, const char *description) :
StopInfo (thread, LLDB_INVALID_UID)
{
if (description)
SetDescription (description);
}
virtual
~StopInfoException ()
{
}
virtual StopReason
GetStopReason () const
{
return eStopReasonException;
}
virtual const char *
GetDescription ()
{
if (m_description.empty())
return "exception";
else
return m_description.c_str();
}
};
//----------------------------------------------------------------------
// StopInfoThreadPlan
//----------------------------------------------------------------------
class StopInfoThreadPlan : public StopInfo
{
public:
StopInfoThreadPlan (ThreadPlanSP &plan_sp, ValueObjectSP &return_valobj_sp) :
StopInfo (plan_sp->GetThread(), LLDB_INVALID_UID),
m_plan_sp (plan_sp),
m_return_valobj_sp (return_valobj_sp)
{
}
virtual ~StopInfoThreadPlan ()
{
}
virtual StopReason
GetStopReason () const
{
return eStopReasonPlanComplete;
}
virtual const char *
GetDescription ()
{
if (m_description.empty())
{
StreamString strm;
m_plan_sp->GetDescription (&strm, eDescriptionLevelBrief);
m_description.swap (strm.GetString());
}
return m_description.c_str();
}
ValueObjectSP
GetReturnValueObject()
{
return m_return_valobj_sp;
}
private:
ThreadPlanSP m_plan_sp;
ValueObjectSP m_return_valobj_sp;
};
} // namespace lldb_private
StopInfoSP
StopInfo::CreateStopReasonWithBreakpointSiteID (Thread &thread, break_id_t break_id)
{
return StopInfoSP (new StopInfoBreakpoint (thread, break_id));
}
StopInfoSP
StopInfo::CreateStopReasonWithBreakpointSiteID (Thread &thread, break_id_t break_id, bool should_stop)
{
return StopInfoSP (new StopInfoBreakpoint (thread, break_id, should_stop));
}
StopInfoSP
StopInfo::CreateStopReasonWithWatchpointID (Thread &thread, break_id_t watch_id)
{
return StopInfoSP (new StopInfoWatchpoint (thread, watch_id));
}
StopInfoSP
StopInfo::CreateStopReasonWithSignal (Thread &thread, int signo)
{
return StopInfoSP (new StopInfoUnixSignal (thread, signo));
}
StopInfoSP
StopInfo::CreateStopReasonToTrace (Thread &thread)
{
return StopInfoSP (new StopInfoTrace (thread));
}
StopInfoSP
StopInfo::CreateStopReasonWithPlan (ThreadPlanSP &plan_sp, ValueObjectSP return_valobj_sp)
{
return StopInfoSP (new StopInfoThreadPlan (plan_sp, return_valobj_sp));
}
StopInfoSP
StopInfo::CreateStopReasonWithException (Thread &thread, const char *description)
{
return StopInfoSP (new StopInfoException (thread, description));
}
ValueObjectSP
StopInfo::GetReturnValueObject(StopInfoSP &stop_info_sp)
{
if (stop_info_sp && stop_info_sp->GetStopReason() == eStopReasonPlanComplete)
{
StopInfoThreadPlan *plan_stop_info = static_cast<StopInfoThreadPlan *>(stop_info_sp.get());
return plan_stop_info->GetReturnValueObject();
}
else
return ValueObjectSP();
}