StopInfo.cpp revision a539e5bd8dc9fcdf1e3dbffff86d9f6fd9750837
1//===-- StopInfo.cpp ---------------------------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "lldb/Target/StopInfo.h"
11
12// C Includes
13// C++ Includes
14#include <string>
15
16// Other libraries and framework includes
17// Project includes
18#include "lldb/Core/Log.h"
19#include "lldb/Breakpoint/Breakpoint.h"
20#include "lldb/Breakpoint/BreakpointLocation.h"
21#include "lldb/Breakpoint/StoppointCallbackContext.h"
22#include "lldb/Breakpoint/Watchpoint.h"
23#include "lldb/Core/Debugger.h"
24#include "lldb/Core/StreamString.h"
25#include "lldb/Expression/ClangUserExpression.h"
26#include "lldb/Target/Target.h"
27#include "lldb/Target/Thread.h"
28#include "lldb/Target/ThreadPlan.h"
29#include "lldb/Target/Process.h"
30#include "lldb/Target/UnixSignals.h"
31
32using namespace lldb;
33using namespace lldb_private;
34
35StopInfo::StopInfo (Thread &thread, uint64_t value) :
36    m_thread (thread),
37    m_stop_id (thread.GetProcess()->GetStopID()),
38    m_resume_id (thread.GetProcess()->GetResumeID()),
39    m_value (value)
40{
41}
42
43bool
44StopInfo::IsValid () const
45{
46    return m_thread.GetProcess()->GetStopID() == m_stop_id;
47}
48
49void
50StopInfo::MakeStopInfoValid ()
51{
52    m_stop_id = m_thread.GetProcess()->GetStopID();
53    m_resume_id = m_thread.GetProcess()->GetResumeID();
54}
55
56bool
57StopInfo::HasTargetRunSinceMe ()
58{
59    lldb::StateType ret_type = m_thread.GetProcess()->GetPrivateState();
60    if (ret_type == eStateRunning)
61    {
62        return true;
63    }
64    else if (ret_type == eStateStopped)
65    {
66        // This is a little tricky.  We want to count "run and stopped again before you could
67        // ask this question as a "TRUE" answer to HasTargetRunSinceMe.  But we don't want to
68        // include any running of the target done for expressions.  So we track both resumes,
69        // and resumes caused by expressions, and check if there are any resumes NOT caused
70        // by expressions.
71
72        uint32_t curr_resume_id = m_thread.GetProcess()->GetResumeID();
73        uint32_t last_user_expression_id = m_thread.GetProcess()->GetLastUserExpressionResumeID ();
74        if (curr_resume_id == m_resume_id)
75        {
76            return false;
77        }
78        else if (curr_resume_id > last_user_expression_id)
79        {
80            return true;
81        }
82    }
83    return false;
84}
85
86//----------------------------------------------------------------------
87// StopInfoBreakpoint
88//----------------------------------------------------------------------
89
90namespace lldb_private
91{
92class StopInfoBreakpoint : public StopInfo
93{
94public:
95
96    StopInfoBreakpoint (Thread &thread, break_id_t break_id) :
97        StopInfo (thread, break_id),
98        m_description(),
99        m_should_stop (false),
100        m_should_stop_is_valid (false),
101        m_should_perform_action (true),
102        m_address (LLDB_INVALID_ADDRESS)
103    {
104        BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
105        if (bp_site_sp)
106        {
107          m_address = bp_site_sp->GetLoadAddress();
108        }
109    }
110
111    StopInfoBreakpoint (Thread &thread, break_id_t break_id, bool should_stop) :
112        StopInfo (thread, break_id),
113        m_description(),
114        m_should_stop (should_stop),
115        m_should_stop_is_valid (true),
116        m_should_perform_action (true),
117        m_address (LLDB_INVALID_ADDRESS)
118    {
119        BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
120        if (bp_site_sp)
121        {
122          m_address = bp_site_sp->GetLoadAddress();
123        }
124    }
125
126    virtual ~StopInfoBreakpoint ()
127    {
128    }
129
130    virtual StopReason
131    GetStopReason () const
132    {
133        return eStopReasonBreakpoint;
134    }
135
136    virtual bool
137    ShouldStopSynchronous (Event *event_ptr)
138    {
139        if (!m_should_stop_is_valid)
140        {
141            // Only check once if we should stop at a breakpoint
142            BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
143            if (bp_site_sp)
144            {
145                ExecutionContext exe_ctx (m_thread.GetStackFrameAtIndex(0));
146                StoppointCallbackContext context (event_ptr, exe_ctx, true);
147                m_should_stop = bp_site_sp->ShouldStop (&context);
148            }
149            else
150            {
151                LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
152
153                if (log)
154                    log->Printf ("Process::%s could not find breakpoint site id: %lld...", __FUNCTION__, m_value);
155
156                m_should_stop = true;
157            }
158            m_should_stop_is_valid = true;
159        }
160        return m_should_stop;
161    }
162
163    bool
164    ShouldStop (Event *event_ptr)
165    {
166        // This just reports the work done by PerformAction or the synchronous stop.  It should
167        // only ever get called after they have had a chance to run.
168        assert (m_should_stop_is_valid);
169        return m_should_stop;
170    }
171
172    virtual void
173    PerformAction (Event *event_ptr)
174    {
175        if (!m_should_perform_action)
176            return;
177        m_should_perform_action = false;
178
179        LogSP log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_BREAKPOINTS);
180
181        BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
182
183        if (bp_site_sp)
184        {
185            size_t num_owners = bp_site_sp->GetNumberOfOwners();
186
187            if (num_owners == 0)
188            {
189                m_should_stop = true;
190            }
191            else
192            {
193                // We go through each location, and test first its condition.  If the condition says to stop,
194                // then we run the callback for that location.  If that callback says to stop as well, then
195                // we set m_should_stop to true; we are going to stop.
196                // But we still want to give all the breakpoints whose conditions say we are going to stop a
197                // chance to run their callbacks.
198                // Of course if any callback restarts the target by putting "continue" in the callback, then
199                // we're going to restart, without running the rest of the callbacks.  And in this case we will
200                // end up not stopping even if another location said we should stop.  But that's better than not
201                // running all the callbacks.
202
203                m_should_stop = false;
204
205                ExecutionContext exe_ctx (m_thread.GetStackFrameAtIndex(0));
206                StoppointCallbackContext context (event_ptr, exe_ctx, false);
207
208                for (size_t j = 0; j < num_owners; j++)
209                {
210                    lldb::BreakpointLocationSP bp_loc_sp = bp_site_sp->GetOwnerAtIndex(j);
211
212                    // First run the condition for the breakpoint.  If that says we should stop, then we'll run
213                    // the callback for the breakpoint.  If the callback says we shouldn't stop that will win.
214
215                    bool condition_says_stop = true;
216                    if (bp_loc_sp->GetConditionText() != NULL)
217                    {
218                        // We need to make sure the user sees any parse errors in their condition, so we'll hook the
219                        // constructor errors up to the debugger's Async I/O.
220
221                        ValueObjectSP result_valobj_sp;
222
223                        ExecutionResults result_code;
224                        ValueObjectSP result_value_sp;
225                        const bool discard_on_error = true;
226                        Error error;
227                        result_code = ClangUserExpression::EvaluateWithError (exe_ctx,
228                                                                              eExecutionPolicyOnlyWhenNeeded,
229                                                                              lldb::eLanguageTypeUnknown,
230                                                                              ClangUserExpression::eResultTypeAny,
231                                                                              discard_on_error,
232                                                                              bp_loc_sp->GetConditionText(),
233                                                                              NULL,
234                                                                              result_value_sp,
235                                                                              error);
236                        if (result_code == eExecutionCompleted)
237                        {
238                            if (result_value_sp)
239                            {
240                                Scalar scalar_value;
241                                if (result_value_sp->ResolveValue (scalar_value))
242                                {
243                                    if (scalar_value.ULongLong(1) == 0)
244                                        condition_says_stop = false;
245                                    else
246                                        condition_says_stop = true;
247                                    if (log)
248                                        log->Printf("Condition successfully evaluated, result is %s.\n",
249                                                    m_should_stop ? "true" : "false");
250                                }
251                                else
252                                {
253                                    condition_says_stop = true;
254                                    if (log)
255                                        log->Printf("Failed to get an integer result from the expression.");
256                                }
257                            }
258                        }
259                        else
260                        {
261                            Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger();
262                            StreamSP error_sp = debugger.GetAsyncErrorStream ();
263                            error_sp->Printf ("Stopped due to an error evaluating condition of breakpoint ");
264                            bp_loc_sp->GetDescription (error_sp.get(), eDescriptionLevelBrief);
265                            error_sp->Printf (": \"%s\"",
266                                              bp_loc_sp->GetConditionText());
267                            error_sp->EOL();
268                            const char *err_str = error.AsCString("<Unknown Error>");
269                            if (log)
270                                log->Printf("Error evaluating condition: \"%s\"\n", err_str);
271
272                            error_sp->PutCString (err_str);
273                            error_sp->EOL();
274                            error_sp->Flush();
275                            // If the condition fails to be parsed or run, we should stop.
276                            condition_says_stop = true;
277                        }
278                    }
279
280                    // If this location's condition says we should aren't going to stop,
281                    // then don't run the callback for this location.
282                    if (!condition_says_stop)
283                        continue;
284
285                    bool callback_says_stop;
286
287                    // FIXME: For now the callbacks have to run in async mode - the first time we restart we need
288                    // to get out of there.  So set it here.
289                    // When we figure out how to nest breakpoint hits then this will change.
290
291                    Debugger &debugger = m_thread.CalculateTarget()->GetDebugger();
292                    bool old_async = debugger.GetAsyncExecution();
293                    debugger.SetAsyncExecution (true);
294
295                    callback_says_stop = bp_loc_sp->InvokeCallback (&context);
296
297                    debugger.SetAsyncExecution (old_async);
298
299                    if (callback_says_stop)
300                        m_should_stop = true;
301
302                    // Also make sure that the callback hasn't continued the target.
303                    // If it did, when we'll set m_should_start to false and get out of here.
304                    if (HasTargetRunSinceMe ())
305                    {
306                        m_should_stop = false;
307                        break;
308                    }
309                }
310            }
311            // We've figured out what this stop wants to do, so mark it as valid so we don't compute it again.
312            m_should_stop_is_valid = true;
313
314        }
315        else
316        {
317            m_should_stop = true;
318            m_should_stop_is_valid = true;
319            LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
320
321            if (log)
322                log->Printf ("Process::%s could not find breakpoint site id: %lld...", __FUNCTION__, m_value);
323        }
324        if (log)
325            log->Printf ("Process::%s returning from action with m_should_stop: %d.", __FUNCTION__, m_should_stop);
326    }
327
328    virtual bool
329    ShouldNotify (Event *event_ptr)
330    {
331        BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
332        if (bp_site_sp)
333        {
334            bool all_internal = true;
335
336            for (uint32_t i = 0; i < bp_site_sp->GetNumberOfOwners(); i++)
337            {
338                if (!bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint().IsInternal())
339                {
340                    all_internal = false;
341                    break;
342                }
343            }
344            return all_internal == false;
345        }
346        return true;
347    }
348
349    virtual const char *
350    GetDescription ()
351    {
352        if (m_description.empty())
353        {
354            BreakpointSiteSP bp_site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (m_value));
355            if (bp_site_sp)
356            {
357                StreamString strm;
358                strm.Printf("breakpoint ");
359                bp_site_sp->GetDescription(&strm, eDescriptionLevelBrief);
360                m_description.swap (strm.GetString());
361            }
362            else
363            {
364                StreamString strm;
365                if (m_address == LLDB_INVALID_ADDRESS)
366                    strm.Printf("breakpoint site %lli which has been deleted - unknown address", m_value);
367                else
368                    strm.Printf("breakpoint site %lli which has been deleted - was at 0x%llx", m_value, m_address);
369                m_description.swap (strm.GetString());
370            }
371        }
372        return m_description.c_str();
373    }
374
375private:
376    std::string m_description;
377    bool m_should_stop;
378    bool m_should_stop_is_valid;
379    bool m_should_perform_action; // Since we are trying to preserve the "state" of the system even if we run functions
380                                  // etc. behind the users backs, we need to make sure we only REALLY perform the action once.
381    lldb::addr_t m_address;       // We use this to capture the breakpoint site address when we create the StopInfo,
382                                  // in case somebody deletes it between the time the StopInfo is made and the
383                                  // description is asked for.
384};
385
386
387//----------------------------------------------------------------------
388// StopInfoWatchpoint
389//----------------------------------------------------------------------
390
391class StopInfoWatchpoint : public StopInfo
392{
393public:
394
395    StopInfoWatchpoint (Thread &thread, break_id_t watch_id) :
396        StopInfo(thread, watch_id),
397        m_description(),
398        m_should_stop(false),
399        m_should_stop_is_valid(false)
400    {
401    }
402
403    virtual ~StopInfoWatchpoint ()
404    {
405    }
406
407    virtual StopReason
408    GetStopReason () const
409    {
410        return eStopReasonWatchpoint;
411    }
412
413    virtual bool
414    ShouldStop (Event *event_ptr)
415    {
416        // ShouldStop() method is idempotent and should not affect hit count.
417        // See Process::RunPrivateStateThread()->Process()->HandlePrivateEvent()
418        // -->Process()::ShouldBroadcastEvent()->ThreadList::ShouldStop()->
419        // Thread::ShouldStop()->ThreadPlanBase::ShouldStop()->
420        // StopInfoWatchpoint::ShouldStop() and
421        // Event::DoOnRemoval()->Process::ProcessEventData::DoOnRemoval()->
422        // StopInfoWatchpoint::PerformAction().
423        if (m_should_stop_is_valid)
424            return m_should_stop;
425
426        WatchpointSP wp_sp =
427            m_thread.CalculateTarget()->GetWatchpointList().FindByID(GetValue());
428        if (wp_sp)
429        {
430            // Check if we should stop at a watchpoint.
431            ExecutionContext exe_ctx (m_thread.GetStackFrameAtIndex(0));
432            StoppointCallbackContext context (event_ptr, exe_ctx, true);
433            m_should_stop = wp_sp->ShouldStop (&context);
434        }
435        else
436        {
437            LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
438
439            if (log)
440                log->Printf ("Process::%s could not find watchpoint location id: %lld...",
441                             __FUNCTION__, GetValue());
442
443            m_should_stop = true;
444        }
445        m_should_stop_is_valid = true;
446        return m_should_stop;
447    }
448
449    // Make sure watchpoint is properly disabled and subsequently enabled while performing watchpoint actions.
450    class WatchpointSentry {
451    public:
452        WatchpointSentry(Process *p, Watchpoint *w):
453            process(p),
454            watchpoint(w)
455        {
456            if (process && watchpoint)
457            {
458                watchpoint->TurnOnEphemeralMode();
459                process->DisableWatchpoint(watchpoint);
460            }
461        }
462        ~WatchpointSentry()
463        {
464            if (process && watchpoint)
465            {
466                if (!watchpoint->IsDisabledDuringEphemeralMode())
467                    process->EnableWatchpoint(watchpoint);
468                watchpoint->TurnOffEphemeralMode();
469            }
470        }
471    private:
472        Process *process;
473        Watchpoint *watchpoint;
474    };
475
476    // Perform any action that is associated with this stop.  This is done as the
477    // Event is removed from the event queue.
478    virtual void
479    PerformAction (Event *event_ptr)
480    {
481        LogSP log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_WATCHPOINTS);
482        // We're going to calculate if we should stop or not in some way during the course of
483        // this code.  Also by default we're going to stop, so set that here.
484        m_should_stop = true;
485
486        WatchpointSP wp_sp =
487            m_thread.CalculateTarget()->GetWatchpointList().FindByID(GetValue());
488        if (wp_sp)
489        {
490            ExecutionContext exe_ctx (m_thread.GetStackFrameAtIndex(0));
491            Process* process = exe_ctx.GetProcessPtr();
492
493            // This sentry object makes sure the current watchpoint is disabled while performing watchpoint actions,
494            // and it is then enabled after we are finished.
495            WatchpointSentry sentry(process, wp_sp.get());
496
497            {
498                // check if this process is running on an architecture where watchpoints trigger
499				// before the associated instruction runs. if so, disable the WP, single-step and then
500				// re-enable the watchpoint
501                if (process)
502                {
503                    uint32_t num; bool wp_triggers_after;
504                    if (process->GetWatchpointSupportInfo(num, wp_triggers_after).Success())
505                    {
506                        if (!wp_triggers_after)
507                        {
508                            ThreadPlan *new_plan = m_thread.QueueThreadPlanForStepSingleInstruction(false, // step-over
509                                                                                                    false, // abort_other_plans
510                                                                                                    true); // stop_other_threads
511                            new_plan->SetIsMasterPlan (true);
512                            new_plan->SetOkayToDiscard (false);
513                            process->GetThreadList().SetSelectedThreadByID (m_thread.GetID());
514                            process->Resume ();
515                            process->WaitForProcessToStop (NULL);
516                            process->GetThreadList().SetSelectedThreadByID (m_thread.GetID());
517                            MakeStopInfoValid(); // make sure we do not fail to stop because of the single-step taken above
518                        }
519                    }
520                }
521            }
522
523            // Record the snapshot of our watchpoint.
524            VariableSP var_sp;
525            ValueObjectSP valobj_sp;
526            StackFrame *frame = exe_ctx.GetFramePtr();
527            if (frame)
528            {
529                bool snapshot_taken = true;
530                if (!wp_sp->IsWatchVariable())
531                {
532                    // We are not watching a variable, just read from the process memory for the watched location.
533                    assert (process);
534                    Error error;
535                    uint64_t val = process->ReadUnsignedIntegerFromMemory(wp_sp->GetLoadAddress(),
536                                                                          wp_sp->GetByteSize(),
537                                                                          0,
538                                                                          error);
539                    if (log)
540                    {
541                        if (error.Success())
542                            log->Printf("Watchpoint snapshot val taken: 0x%llx\n", val);
543                        else
544                            log->Printf("Watchpoint snapshot val taking failed.\n");
545                    }
546                    wp_sp->SetNewSnapshotVal(val);
547                }
548                else if (!wp_sp->GetWatchSpec().empty())
549                {
550                    // Use our frame to evaluate the variable expression.
551                    Error error;
552                    uint32_t expr_path_options = StackFrame::eExpressionPathOptionCheckPtrVsMember |
553                                                 StackFrame::eExpressionPathOptionsAllowDirectIVarAccess;
554                    valobj_sp = frame->GetValueForVariableExpressionPath (wp_sp->GetWatchSpec().c_str(),
555                                                                          eNoDynamicValues,
556                                                                          expr_path_options,
557                                                                          var_sp,
558                                                                          error);
559                    if (valobj_sp)
560                    {
561                        // We're in business.
562                        StreamString ss;
563                        ValueObject::DumpValueObject(ss, valobj_sp.get());
564                        wp_sp->SetNewSnapshot(ss.GetString());
565                    }
566                    else
567                    {
568                        // The variable expression has become out of scope?
569                        // Let us forget about this stop info.
570                        if (log)
571                            log->Printf("Snapshot attempt failed.  Variable expression has become out of scope?");
572                        snapshot_taken = false;
573                        m_should_stop = false;
574                        wp_sp->IncrementFalseAlarmsAndReviseHitCount();
575                    }
576
577                    if (log && snapshot_taken)
578                        log->Printf("Watchpoint snapshot taken: '%s'\n", wp_sp->GetNewSnapshot().c_str());
579                }
580
581                // Now dump the snapshots we have taken.
582                if (snapshot_taken)
583                {
584                    Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger();
585                    StreamSP output_sp = debugger.GetAsyncOutputStream ();
586                    wp_sp->DumpSnapshots(output_sp.get());
587                    output_sp->EOL();
588                    output_sp->Flush();
589                }
590            }
591
592            if (m_should_stop && wp_sp->GetConditionText() != NULL)
593            {
594                // We need to make sure the user sees any parse errors in their condition, so we'll hook the
595                // constructor errors up to the debugger's Async I/O.
596                ExecutionResults result_code;
597                ValueObjectSP result_value_sp;
598                const bool discard_on_error = true;
599                Error error;
600                result_code = ClangUserExpression::EvaluateWithError (exe_ctx,
601                                                                      eExecutionPolicyOnlyWhenNeeded,
602                                                                      lldb::eLanguageTypeUnknown,
603                                                                      ClangUserExpression::eResultTypeAny,
604                                                                      discard_on_error,
605                                                                      wp_sp->GetConditionText(),
606                                                                      NULL,
607                                                                      result_value_sp,
608                                                                      error,
609                                                                      500000);
610                if (result_code == eExecutionCompleted)
611                {
612                    if (result_value_sp)
613                    {
614                        Scalar scalar_value;
615                        if (result_value_sp->ResolveValue (scalar_value))
616                        {
617                            if (scalar_value.ULongLong(1) == 0)
618                            {
619                                // We have been vetoed.  This takes precedence over querying
620                                // the watchpoint whether it should stop (aka ignore count and
621                                // friends).  See also StopInfoWatchpoint::ShouldStop() as well
622                                // as Process::ProcessEventData::DoOnRemoval().
623                                m_should_stop = false;
624                            }
625                            else
626                                m_should_stop = true;
627                            if (log)
628                                log->Printf("Condition successfully evaluated, result is %s.\n",
629                                            m_should_stop ? "true" : "false");
630                        }
631                        else
632                        {
633                            m_should_stop = true;
634                            if (log)
635                                log->Printf("Failed to get an integer result from the expression.");
636                        }
637                    }
638                }
639                else
640                {
641                    Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger();
642                    StreamSP error_sp = debugger.GetAsyncErrorStream ();
643                    error_sp->Printf ("Stopped due to an error evaluating condition of watchpoint ");
644                    wp_sp->GetDescription (error_sp.get(), eDescriptionLevelBrief);
645                    error_sp->Printf (": \"%s\"",
646                                      wp_sp->GetConditionText());
647                    error_sp->EOL();
648                    const char *err_str = error.AsCString("<Unknown Error>");
649                    if (log)
650                        log->Printf("Error evaluating condition: \"%s\"\n", err_str);
651
652                    error_sp->PutCString (err_str);
653                    error_sp->EOL();
654                    error_sp->Flush();
655                    // If the condition fails to be parsed or run, we should stop.
656                    m_should_stop = true;
657                }
658            }
659
660            // If the condition says to stop, we run the callback to further decide whether to stop.
661            if (m_should_stop)
662            {
663                StoppointCallbackContext context (event_ptr, exe_ctx, false);
664                bool stop_requested = wp_sp->InvokeCallback (&context);
665                // Also make sure that the callback hasn't continued the target.
666                // If it did, when we'll set m_should_stop to false and get out of here.
667                if (HasTargetRunSinceMe ())
668                    m_should_stop = false;
669
670                if (m_should_stop && !stop_requested)
671                {
672                    // We have been vetoed by the callback mechanism.
673                    m_should_stop = false;
674                }
675            }
676        }
677        else
678        {
679            LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
680
681            if (log)
682                log->Printf ("Process::%s could not find watchpoint id: %lld...", __FUNCTION__, m_value);
683        }
684        if (log)
685            log->Printf ("Process::%s returning from action with m_should_stop: %d.", __FUNCTION__, m_should_stop);
686    }
687
688    virtual const char *
689    GetDescription ()
690    {
691        if (m_description.empty())
692        {
693            StreamString strm;
694            strm.Printf("watchpoint %lli", m_value);
695            m_description.swap (strm.GetString());
696        }
697        return m_description.c_str();
698    }
699
700private:
701    std::string m_description;
702    bool m_should_stop;
703    bool m_should_stop_is_valid;
704};
705
706
707
708//----------------------------------------------------------------------
709// StopInfoUnixSignal
710//----------------------------------------------------------------------
711
712class StopInfoUnixSignal : public StopInfo
713{
714public:
715
716    StopInfoUnixSignal (Thread &thread, int signo) :
717        StopInfo (thread, signo)
718    {
719    }
720
721    virtual ~StopInfoUnixSignal ()
722    {
723    }
724
725
726    virtual StopReason
727    GetStopReason () const
728    {
729        return eStopReasonSignal;
730    }
731
732    virtual bool
733    ShouldStop (Event *event_ptr)
734    {
735        return m_thread.GetProcess()->GetUnixSignals().GetShouldStop (m_value);
736    }
737
738
739    // If should stop returns false, check if we should notify of this event
740    virtual bool
741    ShouldNotify (Event *event_ptr)
742    {
743        return m_thread.GetProcess()->GetUnixSignals().GetShouldNotify (m_value);
744    }
745
746
747    virtual void
748    WillResume (lldb::StateType resume_state)
749    {
750        if (m_thread.GetProcess()->GetUnixSignals().GetShouldSuppress(m_value) == false)
751            m_thread.SetResumeSignal(m_value);
752    }
753
754    virtual const char *
755    GetDescription ()
756    {
757        if (m_description.empty())
758        {
759            StreamString strm;
760            const char *signal_name = m_thread.GetProcess()->GetUnixSignals().GetSignalAsCString (m_value);
761            if (signal_name)
762                strm.Printf("signal %s", signal_name);
763            else
764                strm.Printf("signal %lli", m_value);
765            m_description.swap (strm.GetString());
766        }
767        return m_description.c_str();
768    }
769};
770
771//----------------------------------------------------------------------
772// StopInfoTrace
773//----------------------------------------------------------------------
774
775class StopInfoTrace : public StopInfo
776{
777public:
778
779    StopInfoTrace (Thread &thread) :
780        StopInfo (thread, LLDB_INVALID_UID)
781    {
782    }
783
784    virtual ~StopInfoTrace ()
785    {
786    }
787
788    virtual StopReason
789    GetStopReason () const
790    {
791        return eStopReasonTrace;
792    }
793
794    virtual const char *
795    GetDescription ()
796    {
797        if (m_description.empty())
798        return "trace";
799        else
800            return m_description.c_str();
801    }
802};
803
804
805//----------------------------------------------------------------------
806// StopInfoException
807//----------------------------------------------------------------------
808
809class StopInfoException : public StopInfo
810{
811public:
812
813    StopInfoException (Thread &thread, const char *description) :
814        StopInfo (thread, LLDB_INVALID_UID)
815    {
816        if (description)
817            SetDescription (description);
818    }
819
820    virtual
821    ~StopInfoException ()
822    {
823    }
824
825    virtual StopReason
826    GetStopReason () const
827    {
828        return eStopReasonException;
829    }
830
831    virtual const char *
832    GetDescription ()
833    {
834        if (m_description.empty())
835            return "exception";
836        else
837            return m_description.c_str();
838    }
839};
840
841
842//----------------------------------------------------------------------
843// StopInfoThreadPlan
844//----------------------------------------------------------------------
845
846class StopInfoThreadPlan : public StopInfo
847{
848public:
849
850    StopInfoThreadPlan (ThreadPlanSP &plan_sp, ValueObjectSP &return_valobj_sp) :
851        StopInfo (plan_sp->GetThread(), LLDB_INVALID_UID),
852        m_plan_sp (plan_sp),
853        m_return_valobj_sp (return_valobj_sp)
854    {
855    }
856
857    virtual ~StopInfoThreadPlan ()
858    {
859    }
860
861    virtual StopReason
862    GetStopReason () const
863    {
864        return eStopReasonPlanComplete;
865    }
866
867    virtual const char *
868    GetDescription ()
869    {
870        if (m_description.empty())
871        {
872            StreamString strm;
873            m_plan_sp->GetDescription (&strm, eDescriptionLevelBrief);
874            m_description.swap (strm.GetString());
875        }
876        return m_description.c_str();
877    }
878
879    ValueObjectSP
880    GetReturnValueObject()
881    {
882        return m_return_valobj_sp;
883    }
884
885private:
886    ThreadPlanSP m_plan_sp;
887    ValueObjectSP m_return_valobj_sp;
888};
889} // namespace lldb_private
890
891StopInfoSP
892StopInfo::CreateStopReasonWithBreakpointSiteID (Thread &thread, break_id_t break_id)
893{
894    return StopInfoSP (new StopInfoBreakpoint (thread, break_id));
895}
896
897StopInfoSP
898StopInfo::CreateStopReasonWithBreakpointSiteID (Thread &thread, break_id_t break_id, bool should_stop)
899{
900    return StopInfoSP (new StopInfoBreakpoint (thread, break_id, should_stop));
901}
902
903StopInfoSP
904StopInfo::CreateStopReasonWithWatchpointID (Thread &thread, break_id_t watch_id)
905{
906    return StopInfoSP (new StopInfoWatchpoint (thread, watch_id));
907}
908
909StopInfoSP
910StopInfo::CreateStopReasonWithSignal (Thread &thread, int signo)
911{
912    return StopInfoSP (new StopInfoUnixSignal (thread, signo));
913}
914
915StopInfoSP
916StopInfo::CreateStopReasonToTrace (Thread &thread)
917{
918    return StopInfoSP (new StopInfoTrace (thread));
919}
920
921StopInfoSP
922StopInfo::CreateStopReasonWithPlan (ThreadPlanSP &plan_sp, ValueObjectSP return_valobj_sp)
923{
924    return StopInfoSP (new StopInfoThreadPlan (plan_sp, return_valobj_sp));
925}
926
927StopInfoSP
928StopInfo::CreateStopReasonWithException (Thread &thread, const char *description)
929{
930    return StopInfoSP (new StopInfoException (thread, description));
931}
932
933ValueObjectSP
934StopInfo::GetReturnValueObject(StopInfoSP &stop_info_sp)
935{
936    if (stop_info_sp && stop_info_sp->GetStopReason() == eStopReasonPlanComplete)
937    {
938        StopInfoThreadPlan *plan_stop_info = static_cast<StopInfoThreadPlan *>(stop_info_sp.get());
939        return plan_stop_info->GetReturnValueObject();
940    }
941    else
942        return ValueObjectSP();
943}
944