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/lldb-python.h"
11 
12 #include "lldb/Target/StopInfo.h"
13 
14 // C Includes
15 // C++ Includes
16 #include <string>
17 
18 // Other libraries and framework includes
19 // Project includes
20 #include "lldb/Core/Log.h"
21 #include "lldb/Breakpoint/Breakpoint.h"
22 #include "lldb/Breakpoint/BreakpointLocation.h"
23 #include "lldb/Breakpoint/StoppointCallbackContext.h"
24 #include "lldb/Breakpoint/Watchpoint.h"
25 #include "lldb/Core/Debugger.h"
26 #include "lldb/Core/StreamString.h"
27 #include "lldb/Expression/ClangUserExpression.h"
28 #include "lldb/Target/Target.h"
29 #include "lldb/Target/Thread.h"
30 #include "lldb/Target/ThreadPlan.h"
31 #include "lldb/Target/Process.h"
32 #include "lldb/Target/UnixSignals.h"
33 
34 using namespace lldb;
35 using namespace lldb_private;
36 
37 StopInfo::StopInfo (Thread &thread, uint64_t value) :
38     m_thread_wp (thread.shared_from_this()),
39     m_stop_id (thread.GetProcess()->GetStopID()),
40     m_resume_id (thread.GetProcess()->GetResumeID()),
41     m_value (value),
42     m_override_should_notify (eLazyBoolCalculate),
43     m_override_should_stop (eLazyBoolCalculate)
44 {
45 }
46 
47 bool
48 StopInfo::IsValid () const
49 {
50     ThreadSP thread_sp (m_thread_wp.lock());
51     if (thread_sp)
52         return thread_sp->GetProcess()->GetStopID() == m_stop_id;
53     return false;
54 }
55 
56 void
57 StopInfo::MakeStopInfoValid ()
58 {
59     ThreadSP thread_sp (m_thread_wp.lock());
60     if (thread_sp)
61     {
62         m_stop_id = thread_sp->GetProcess()->GetStopID();
63         m_resume_id = thread_sp->GetProcess()->GetResumeID();
64     }
65 }
66 
67 bool
68 StopInfo::HasTargetRunSinceMe ()
69 {
70     ThreadSP thread_sp (m_thread_wp.lock());
71 
72     if (thread_sp)
73     {
74         lldb::StateType ret_type = thread_sp->GetProcess()->GetPrivateState();
75         if (ret_type == eStateRunning)
76         {
77             return true;
78         }
79         else if (ret_type == eStateStopped)
80         {
81             // This is a little tricky.  We want to count "run and stopped again before you could
82             // ask this question as a "TRUE" answer to HasTargetRunSinceMe.  But we don't want to
83             // include any running of the target done for expressions.  So we track both resumes,
84             // and resumes caused by expressions, and check if there are any resumes NOT caused
85             // by expressions.
86 
87             uint32_t curr_resume_id = thread_sp->GetProcess()->GetResumeID();
88             uint32_t last_user_expression_id = thread_sp->GetProcess()->GetLastUserExpressionResumeID ();
89             if (curr_resume_id == m_resume_id)
90             {
91                 return false;
92             }
93             else if (curr_resume_id > last_user_expression_id)
94             {
95                 return true;
96             }
97         }
98     }
99     return false;
100 }
101 
102 //----------------------------------------------------------------------
103 // StopInfoBreakpoint
104 //----------------------------------------------------------------------
105 
106 namespace lldb_private
107 {
108 class StopInfoBreakpoint : public StopInfo
109 {
110 public:
111 
112     StopInfoBreakpoint (Thread &thread, break_id_t break_id) :
113         StopInfo (thread, break_id),
114         m_description(),
115         m_should_stop (false),
116         m_should_stop_is_valid (false),
117         m_should_perform_action (true),
118         m_address (LLDB_INVALID_ADDRESS),
119         m_break_id(LLDB_INVALID_BREAK_ID),
120         m_was_one_shot (false)
121     {
122         StoreBPInfo();
123     }
124 
125     StopInfoBreakpoint (Thread &thread, break_id_t break_id, bool should_stop) :
126         StopInfo (thread, break_id),
127         m_description(),
128         m_should_stop (should_stop),
129         m_should_stop_is_valid (true),
130         m_should_perform_action (true),
131         m_address (LLDB_INVALID_ADDRESS),
132         m_break_id(LLDB_INVALID_BREAK_ID),
133         m_was_one_shot (false)
134     {
135         StoreBPInfo();
136     }
137 
138     void
139     StoreBPInfo ()
140     {
141         ThreadSP thread_sp (m_thread_wp.lock());
142         if (thread_sp)
143         {
144             BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value));
145             if (bp_site_sp)
146             {
147                 if (bp_site_sp->GetNumberOfOwners() == 1)
148                 {
149                     BreakpointLocationSP bp_loc_sp = bp_site_sp->GetOwnerAtIndex(0);
150                     if (bp_loc_sp)
151                     {
152                         m_break_id = bp_loc_sp->GetBreakpoint().GetID();
153                         m_was_one_shot = bp_loc_sp->GetBreakpoint().IsOneShot();
154                     }
155                 }
156                 m_address = bp_site_sp->GetLoadAddress();
157             }
158         }
159     }
160 
161     virtual ~StopInfoBreakpoint ()
162     {
163     }
164 
165     virtual StopReason
166     GetStopReason () const
167     {
168         return eStopReasonBreakpoint;
169     }
170 
171     virtual bool
172     ShouldStopSynchronous (Event *event_ptr)
173     {
174         ThreadSP thread_sp (m_thread_wp.lock());
175         if (thread_sp)
176         {
177             if (!m_should_stop_is_valid)
178             {
179                 // Only check once if we should stop at a breakpoint
180                 BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value));
181                 if (bp_site_sp)
182                 {
183                     ExecutionContext exe_ctx (thread_sp->GetStackFrameAtIndex(0));
184                     StoppointCallbackContext context (event_ptr, exe_ctx, true);
185                     m_should_stop = bp_site_sp->ShouldStop (&context);
186                 }
187                 else
188                 {
189                     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
190 
191                     if (log)
192                         log->Printf ("Process::%s could not find breakpoint site id: %" PRId64 "...", __FUNCTION__, m_value);
193 
194                     m_should_stop = true;
195                 }
196                 m_should_stop_is_valid = true;
197             }
198             return m_should_stop;
199         }
200         return false;
201     }
202 
203     virtual bool
204     DoShouldNotify (Event *event_ptr)
205     {
206         ThreadSP thread_sp (m_thread_wp.lock());
207         if (thread_sp)
208         {
209             BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value));
210             if (bp_site_sp)
211             {
212                 bool all_internal = true;
213 
214                 for (uint32_t i = 0; i < bp_site_sp->GetNumberOfOwners(); i++)
215                 {
216                     if (!bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint().IsInternal())
217                     {
218                         all_internal = false;
219                         break;
220                     }
221                 }
222                 return all_internal == false;
223             }
224         }
225         return true;
226     }
227 
228     virtual const char *
229     GetDescription ()
230     {
231         if (m_description.empty())
232         {
233             ThreadSP thread_sp (m_thread_wp.lock());
234             if (thread_sp)
235             {
236                 BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value));
237                 if (bp_site_sp)
238                 {
239                     StreamString strm;
240                     // If we have just hit an internal breakpoint, and it has a kind description, print that instead of the
241                     // full breakpoint printing:
242                     if (bp_site_sp->IsInternal())
243                     {
244                         size_t num_owners = bp_site_sp->GetNumberOfOwners();
245                         for (size_t idx = 0; idx < num_owners; idx++)
246                         {
247                             const char *kind = bp_site_sp->GetOwnerAtIndex(idx)->GetBreakpoint().GetBreakpointKind();
248                             if (kind != NULL)
249                             {
250                                 m_description.assign (kind);
251                                 return kind;
252                             }
253                         }
254                     }
255 
256                     strm.Printf("breakpoint ");
257                     bp_site_sp->GetDescription(&strm, eDescriptionLevelBrief);
258                     m_description.swap (strm.GetString());
259                 }
260                 else
261                 {
262                     StreamString strm;
263                     if (m_break_id != LLDB_INVALID_BREAK_ID)
264                     {
265                         BreakpointSP break_sp = thread_sp->GetProcess()->GetTarget().GetBreakpointByID(m_break_id);
266                         if (break_sp)
267                         {
268                             if (break_sp->IsInternal())
269                             {
270                                 const char *kind = break_sp->GetBreakpointKind();
271                                 if (kind)
272                                     strm.Printf ("internal %s breakpoint(%d).", kind, m_break_id);
273                                 else
274                                     strm.Printf ("internal breakpoint(%d).", m_break_id);
275                             }
276                             else
277                             {
278                                 strm.Printf ("breakpoint %d.", m_break_id);
279                             }
280                         }
281                         else
282                         {
283                             if (m_was_one_shot)
284                                 strm.Printf ("one-shot breakpoint %d", m_break_id);
285                             else
286                                 strm.Printf ("breakpoint %d which has been deleted.", m_break_id);
287                         }
288                     }
289                     else if (m_address == LLDB_INVALID_ADDRESS)
290                         strm.Printf("breakpoint site %" PRIi64 " which has been deleted - unknown address", m_value);
291                     else
292                         strm.Printf("breakpoint site %" PRIi64 " which has been deleted - was at 0x%" PRIx64, m_value, m_address);
293 
294                     m_description.swap (strm.GetString());
295                 }
296             }
297         }
298         return m_description.c_str();
299     }
300 
301 protected:
302     bool
303     ShouldStop (Event *event_ptr)
304     {
305         // This just reports the work done by PerformAction or the synchronous stop.  It should
306         // only ever get called after they have had a chance to run.
307         assert (m_should_stop_is_valid);
308         return m_should_stop;
309     }
310 
311     virtual void
312     PerformAction (Event *event_ptr)
313     {
314         if (!m_should_perform_action)
315             return;
316         m_should_perform_action = false;
317 
318         ThreadSP thread_sp (m_thread_wp.lock());
319 
320         if (thread_sp)
321         {
322             Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_BREAKPOINTS);
323 
324             if (!thread_sp->IsValid())
325             {
326                 // This shouldn't ever happen, but just in case, don't do more harm.
327                 if (log)
328                 {
329                     log->Printf ("PerformAction got called with an invalid thread.");
330                 }
331                 m_should_stop = true;
332                 m_should_stop_is_valid = true;
333                 return;
334             }
335 
336             BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value));
337 
338             if (bp_site_sp)
339             {
340                 size_t num_owners = bp_site_sp->GetNumberOfOwners();
341 
342                 if (num_owners == 0)
343                 {
344                     m_should_stop = true;
345                 }
346                 else
347                 {
348                     // We go through each location, and test first its condition.  If the condition says to stop,
349                     // then we run the callback for that location.  If that callback says to stop as well, then
350                     // we set m_should_stop to true; we are going to stop.
351                     // But we still want to give all the breakpoints whose conditions say we are going to stop a
352                     // chance to run their callbacks.
353                     // Of course if any callback restarts the target by putting "continue" in the callback, then
354                     // we're going to restart, without running the rest of the callbacks.  And in this case we will
355                     // end up not stopping even if another location said we should stop.  But that's better than not
356                     // running all the callbacks.
357 
358                     m_should_stop = false;
359 
360                     ExecutionContext exe_ctx (thread_sp->GetStackFrameAtIndex(0));
361                     Process *process  = exe_ctx.GetProcessPtr();
362                     if (process->GetModIDRef().IsLastResumeForUserExpression())
363                     {
364                         // If we are in the middle of evaluating an expression, don't run asynchronous breakpoint commands or
365                         // expressions.  That could lead to infinite recursion if the command or condition re-calls the function
366                         // with this breakpoint.
367                         // TODO: We can keep a list of the breakpoints we've seen while running expressions in the nested
368                         // PerformAction calls that can arise when the action runs a function that hits another breakpoint,
369                         // and only stop running commands when we see the same breakpoint hit a second time.
370 
371                         m_should_stop_is_valid = true;
372                         if (log)
373                             log->Printf ("StopInfoBreakpoint::PerformAction - Hit a breakpoint while running an expression,"
374                                          " not running commands to avoid recursion.");
375                         bool ignoring_breakpoints = process->GetIgnoreBreakpointsInExpressions();
376                         if (ignoring_breakpoints)
377                         {
378                             m_should_stop = false;
379                             // Internal breakpoints will always stop.
380                             for (size_t j = 0; j < num_owners; j++)
381                             {
382                                 lldb::BreakpointLocationSP bp_loc_sp = bp_site_sp->GetOwnerAtIndex(j);
383                                 if (bp_loc_sp->GetBreakpoint().IsInternal())
384                                 {
385                                     m_should_stop = true;
386                                     break;
387                                 }
388                             }
389                         }
390                         else
391                         {
392                             m_should_stop = true;
393                         }
394                         if (log)
395                             log->Printf ("StopInfoBreakpoint::PerformAction - in expression, continuing: %s.",
396                                          m_should_stop ? "true" : "false");
397                         process->GetTarget().GetDebugger().GetAsyncOutputStream()->Printf("Warning: hit breakpoint while "
398                                                "running function, skipping commands and conditions to prevent recursion.");
399                         return;
400                     }
401 
402                     StoppointCallbackContext context (event_ptr, exe_ctx, false);
403 
404                     // Let's copy the breakpoint locations out of the site and store them in a local list.  That way if
405                     // one of the breakpoint actions changes the site, then we won't be operating on a bad list.
406 
407                     BreakpointLocationCollection site_locations;
408                     for (size_t j = 0; j < num_owners; j++)
409                         site_locations.Add(bp_site_sp->GetOwnerAtIndex(j));
410 
411                     for (size_t j = 0; j < num_owners; j++)
412                     {
413                         lldb::BreakpointLocationSP bp_loc_sp = site_locations.GetByIndex(j);
414 
415                         // If another action disabled this breakpoint or its location, then don't run the actions.
416                         if (!bp_loc_sp->IsEnabled() || !bp_loc_sp->GetBreakpoint().IsEnabled())
417                             continue;
418 
419                         // The breakpoint site may have many locations associated with it, not all of them valid for
420                         // this thread.  Skip the ones that aren't:
421                         if (!bp_loc_sp->ValidForThisThread(thread_sp.get()))
422                         {
423                             if (log)
424                             {
425                                 StreamString s;
426                                 bp_loc_sp->GetDescription(&s, eDescriptionLevelBrief);
427                                 log->Printf ("Breakpoint %s hit on thread 0x%llx but it was not for this thread, continuing.", s.GetData(), thread_sp->GetID());
428                             }
429                             continue;
430                         }
431                         // First run the condition for the breakpoint.  If that says we should stop, then we'll run
432                         // the callback for the breakpoint.  If the callback says we shouldn't stop that will win.
433 
434                         if (bp_loc_sp->GetConditionText() != NULL)
435                         {
436                             Error condition_error;
437                             bool condition_says_stop = bp_loc_sp->ConditionSaysStop(exe_ctx, condition_error);
438 
439                             if (!condition_error.Success())
440                             {
441                                 Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger();
442                                 StreamSP error_sp = debugger.GetAsyncErrorStream ();
443                                 error_sp->Printf ("Stopped due to an error evaluating condition of breakpoint ");
444                                 bp_loc_sp->GetDescription (error_sp.get(), eDescriptionLevelBrief);
445                                 error_sp->Printf (": \"%s\"",
446                                                   bp_loc_sp->GetConditionText());
447                                 error_sp->EOL();
448                                 const char *err_str = condition_error.AsCString("<Unknown Error>");
449                                 if (log)
450                                     log->Printf("Error evaluating condition: \"%s\"\n", err_str);
451 
452                                 error_sp->PutCString (err_str);
453                                 error_sp->EOL();
454                                 error_sp->Flush();
455                             }
456                             else
457                             {
458                                 if (log)
459                                 {
460                                     StreamString s;
461                                     bp_loc_sp->GetDescription(&s, eDescriptionLevelBrief);
462                                     log->Printf ("Condition evaluated for breakpoint %s on thread 0x%llx conditon_says_stop: %i.", s.GetData(), thread_sp->GetID(), condition_says_stop);
463                                 }
464                                 if (!condition_says_stop)
465                                     continue;
466                             }
467                         }
468 
469                         bool callback_says_stop;
470 
471                         // FIXME: For now the callbacks have to run in async mode - the first time we restart we need
472                         // to get out of there.  So set it here.
473                         // When we figure out how to nest breakpoint hits then this will change.
474 
475                         Debugger &debugger = thread_sp->CalculateTarget()->GetDebugger();
476                         bool old_async = debugger.GetAsyncExecution();
477                         debugger.SetAsyncExecution (true);
478 
479                         callback_says_stop = bp_loc_sp->InvokeCallback (&context);
480 
481                         debugger.SetAsyncExecution (old_async);
482 
483                         if (callback_says_stop)
484                             m_should_stop = true;
485 
486                         // If we are going to stop for this breakpoint, then remove the breakpoint.
487                         if (callback_says_stop && bp_loc_sp && bp_loc_sp->GetBreakpoint().IsOneShot())
488                         {
489                             thread_sp->GetProcess()->GetTarget().RemoveBreakpointByID (bp_loc_sp->GetBreakpoint().GetID());
490                         }
491 
492                         // Also make sure that the callback hasn't continued the target.
493                         // If it did, when we'll set m_should_start to false and get out of here.
494                         if (HasTargetRunSinceMe ())
495                         {
496                             m_should_stop = false;
497                             break;
498                         }
499                     }
500                 }
501                 // We've figured out what this stop wants to do, so mark it as valid so we don't compute it again.
502                 m_should_stop_is_valid = true;
503 
504             }
505             else
506             {
507                 m_should_stop = true;
508                 m_should_stop_is_valid = true;
509                 Log * log_process(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
510 
511                 if (log_process)
512                     log_process->Printf ("Process::%s could not find breakpoint site id: %" PRId64 "...", __FUNCTION__, m_value);
513             }
514             if (log)
515                 log->Printf ("Process::%s returning from action with m_should_stop: %d.", __FUNCTION__, m_should_stop);
516         }
517     }
518 
519 private:
520     std::string m_description;
521     bool m_should_stop;
522     bool m_should_stop_is_valid;
523     bool m_should_perform_action; // Since we are trying to preserve the "state" of the system even if we run functions
524                                   // etc. behind the users backs, we need to make sure we only REALLY perform the action once.
525     lldb::addr_t m_address;       // We use this to capture the breakpoint site address when we create the StopInfo,
526                                   // in case somebody deletes it between the time the StopInfo is made and the
527                                   // description is asked for.
528     lldb::break_id_t m_break_id;
529     bool m_was_one_shot;
530 };
531 
532 
533 //----------------------------------------------------------------------
534 // StopInfoWatchpoint
535 //----------------------------------------------------------------------
536 
537 class StopInfoWatchpoint : public StopInfo
538 {
539 public:
540     // Make sure watchpoint is properly disabled and subsequently enabled while performing watchpoint actions.
541     class WatchpointSentry {
542     public:
543         WatchpointSentry(Process *p, Watchpoint *w):
544             process(p),
545             watchpoint(w)
546         {
547             if (process && watchpoint)
548             {
549                 const bool notify = false;
550                 watchpoint->TurnOnEphemeralMode();
551                 process->DisableWatchpoint(watchpoint, notify);
552             }
553         }
554         ~WatchpointSentry()
555         {
556             if (process && watchpoint)
557             {
558                 if (!watchpoint->IsDisabledDuringEphemeralMode())
559                 {
560                     const bool notify = false;
561                     process->EnableWatchpoint(watchpoint, notify);
562                 }
563                 watchpoint->TurnOffEphemeralMode();
564             }
565         }
566     private:
567         Process *process;
568         Watchpoint *watchpoint;
569     };
570 
571     StopInfoWatchpoint (Thread &thread, break_id_t watch_id) :
572         StopInfo(thread, watch_id),
573         m_description(),
574         m_should_stop(false),
575         m_should_stop_is_valid(false)
576     {
577     }
578 
579     virtual ~StopInfoWatchpoint ()
580     {
581     }
582 
583     virtual StopReason
584     GetStopReason () const
585     {
586         return eStopReasonWatchpoint;
587     }
588 
589     virtual const char *
590     GetDescription ()
591     {
592         if (m_description.empty())
593         {
594             StreamString strm;
595             strm.Printf("watchpoint %" PRIi64, m_value);
596             m_description.swap (strm.GetString());
597         }
598         return m_description.c_str();
599     }
600 
601 protected:
602     virtual bool
603     ShouldStopSynchronous (Event *event_ptr)
604     {
605         // ShouldStop() method is idempotent and should not affect hit count.
606         // See Process::RunPrivateStateThread()->Process()->HandlePrivateEvent()
607         // -->Process()::ShouldBroadcastEvent()->ThreadList::ShouldStop()->
608         // Thread::ShouldStop()->ThreadPlanBase::ShouldStop()->
609         // StopInfoWatchpoint::ShouldStop() and
610         // Event::DoOnRemoval()->Process::ProcessEventData::DoOnRemoval()->
611         // StopInfoWatchpoint::PerformAction().
612         if (m_should_stop_is_valid)
613             return m_should_stop;
614 
615         ThreadSP thread_sp (m_thread_wp.lock());
616         if (thread_sp)
617         {
618             WatchpointSP wp_sp (thread_sp->CalculateTarget()->GetWatchpointList().FindByID(GetValue()));
619             if (wp_sp)
620             {
621                 // Check if we should stop at a watchpoint.
622                 ExecutionContext exe_ctx (thread_sp->GetStackFrameAtIndex(0));
623                 StoppointCallbackContext context (event_ptr, exe_ctx, true);
624                 m_should_stop = wp_sp->ShouldStop (&context);
625             }
626             else
627             {
628                 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
629 
630                 if (log)
631                     log->Printf ("Process::%s could not find watchpoint location id: %" PRId64 "...",
632                                  __FUNCTION__, GetValue());
633 
634                 m_should_stop = true;
635             }
636         }
637         m_should_stop_is_valid = true;
638         return m_should_stop;
639     }
640 
641     bool
642     ShouldStop (Event *event_ptr)
643     {
644         // This just reports the work done by PerformAction or the synchronous stop.  It should
645         // only ever get called after they have had a chance to run.
646         assert (m_should_stop_is_valid);
647         return m_should_stop;
648     }
649 
650     virtual void
651     PerformAction (Event *event_ptr)
652     {
653         Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_WATCHPOINTS);
654         // We're going to calculate if we should stop or not in some way during the course of
655         // this code.  Also by default we're going to stop, so set that here.
656         m_should_stop = true;
657 
658         ThreadSP thread_sp (m_thread_wp.lock());
659         if (thread_sp)
660         {
661 
662             WatchpointSP wp_sp (thread_sp->CalculateTarget()->GetWatchpointList().FindByID(GetValue()));
663             if (wp_sp)
664             {
665                 ExecutionContext exe_ctx (thread_sp->GetStackFrameAtIndex(0));
666                 Process* process = exe_ctx.GetProcessPtr();
667 
668                 // This sentry object makes sure the current watchpoint is disabled while performing watchpoint actions,
669                 // and it is then enabled after we are finished.
670                 WatchpointSentry sentry(process, wp_sp.get());
671 
672                 {
673                     // check if this process is running on an architecture where watchpoints trigger
674                     // before the associated instruction runs. if so, disable the WP, single-step and then
675                     // re-enable the watchpoint
676                     if (process)
677                     {
678                         uint32_t num;
679                         bool wp_triggers_after;
680                         if (process->GetWatchpointSupportInfo(num, wp_triggers_after).Success())
681                         {
682                             if (!wp_triggers_after)
683                             {
684                                 StopInfoSP stored_stop_info_sp = thread_sp->GetStopInfo();
685                                 assert (stored_stop_info_sp.get() == this);
686 
687                                 ThreadPlanSP new_plan_sp(thread_sp->QueueThreadPlanForStepSingleInstruction(false, // step-over
688                                                                                                         false,     // abort_other_plans
689                                                                                                         true));    // stop_other_threads
690                                 new_plan_sp->SetIsMasterPlan (true);
691                                 new_plan_sp->SetOkayToDiscard (false);
692                                 new_plan_sp->SetPrivate (true);
693                                 process->GetThreadList().SetSelectedThreadByID (thread_sp->GetID());
694                                 process->Resume ();
695                                 process->WaitForProcessToStop (NULL);
696                                 process->GetThreadList().SetSelectedThreadByID (thread_sp->GetID());
697                                 thread_sp->SetStopInfo(stored_stop_info_sp);
698                             }
699                         }
700                     }
701                 }
702 
703                 if (m_should_stop && wp_sp->GetConditionText() != NULL)
704                 {
705                     // We need to make sure the user sees any parse errors in their condition, so we'll hook the
706                     // constructor errors up to the debugger's Async I/O.
707                     ExecutionResults result_code;
708                     EvaluateExpressionOptions expr_options;
709                     expr_options.SetUnwindOnError(true);
710                     expr_options.SetIgnoreBreakpoints(true);
711                     ValueObjectSP result_value_sp;
712                     Error error;
713                     result_code = ClangUserExpression::Evaluate (exe_ctx,
714                                                                  expr_options,
715                                                                  wp_sp->GetConditionText(),
716                                                                  NULL,
717                                                                  result_value_sp,
718                                                                  error);
719                     if (result_code == eExecutionCompleted)
720                     {
721                         if (result_value_sp)
722                         {
723                             Scalar scalar_value;
724                             if (result_value_sp->ResolveValue (scalar_value))
725                             {
726                                 if (scalar_value.ULongLong(1) == 0)
727                                 {
728                                     // We have been vetoed.  This takes precedence over querying
729                                     // the watchpoint whether it should stop (aka ignore count and
730                                     // friends).  See also StopInfoWatchpoint::ShouldStop() as well
731                                     // as Process::ProcessEventData::DoOnRemoval().
732                                     m_should_stop = false;
733                                 }
734                                 else
735                                     m_should_stop = true;
736                                 if (log)
737                                     log->Printf("Condition successfully evaluated, result is %s.\n",
738                                                 m_should_stop ? "true" : "false");
739                             }
740                             else
741                             {
742                                 m_should_stop = true;
743                                 if (log)
744                                     log->Printf("Failed to get an integer result from the expression.");
745                             }
746                         }
747                     }
748                     else
749                     {
750                         Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger();
751                         StreamSP error_sp = debugger.GetAsyncErrorStream ();
752                         error_sp->Printf ("Stopped due to an error evaluating condition of watchpoint ");
753                         wp_sp->GetDescription (error_sp.get(), eDescriptionLevelBrief);
754                         error_sp->Printf (": \"%s\"",
755                                           wp_sp->GetConditionText());
756                         error_sp->EOL();
757                         const char *err_str = error.AsCString("<Unknown Error>");
758                         if (log)
759                             log->Printf("Error evaluating condition: \"%s\"\n", err_str);
760 
761                         error_sp->PutCString (err_str);
762                         error_sp->EOL();
763                         error_sp->Flush();
764                         // If the condition fails to be parsed or run, we should stop.
765                         m_should_stop = true;
766                     }
767                 }
768 
769                 // If the condition says to stop, we run the callback to further decide whether to stop.
770                 if (m_should_stop)
771                 {
772                     StoppointCallbackContext context (event_ptr, exe_ctx, false);
773                     bool stop_requested = wp_sp->InvokeCallback (&context);
774                     // Also make sure that the callback hasn't continued the target.
775                     // If it did, when we'll set m_should_stop to false and get out of here.
776                     if (HasTargetRunSinceMe ())
777                         m_should_stop = false;
778 
779                     if (m_should_stop && !stop_requested)
780                     {
781                         // We have been vetoed by the callback mechanism.
782                         m_should_stop = false;
783                     }
784                 }
785                 // Finally, if we are going to stop, print out the new & old values:
786                 if (m_should_stop)
787                 {
788                     wp_sp->CaptureWatchedValue(exe_ctx);
789 
790                     Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger();
791                     StreamSP output_sp = debugger.GetAsyncOutputStream ();
792                     wp_sp->DumpSnapshots(output_sp.get());
793                     output_sp->EOL();
794                     output_sp->Flush();
795                 }
796 
797             }
798             else
799             {
800                 Log * log_process(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
801 
802                 if (log_process)
803                     log_process->Printf ("Process::%s could not find watchpoint id: %" PRId64 "...", __FUNCTION__, m_value);
804             }
805             if (log)
806                 log->Printf ("Process::%s returning from action with m_should_stop: %d.", __FUNCTION__, m_should_stop);
807 
808             m_should_stop_is_valid = true;
809         }
810     }
811 
812 private:
813     std::string m_description;
814     bool m_should_stop;
815     bool m_should_stop_is_valid;
816 };
817 
818 
819 
820 //----------------------------------------------------------------------
821 // StopInfoUnixSignal
822 //----------------------------------------------------------------------
823 
824 class StopInfoUnixSignal : public StopInfo
825 {
826 public:
827 
828     StopInfoUnixSignal (Thread &thread, int signo) :
829         StopInfo (thread, signo)
830     {
831     }
832 
833     virtual ~StopInfoUnixSignal ()
834     {
835     }
836 
837 
838     virtual StopReason
839     GetStopReason () const
840     {
841         return eStopReasonSignal;
842     }
843 
844     virtual bool
845     ShouldStopSynchronous (Event *event_ptr)
846     {
847         ThreadSP thread_sp (m_thread_wp.lock());
848         if (thread_sp)
849             return thread_sp->GetProcess()->GetUnixSignals().GetShouldStop (m_value);
850         return false;
851     }
852 
853     virtual bool
854     ShouldStop (Event *event_ptr)
855     {
856         ThreadSP thread_sp (m_thread_wp.lock());
857         if (thread_sp)
858             return thread_sp->GetProcess()->GetUnixSignals().GetShouldStop (m_value);
859         return false;
860     }
861 
862 
863     // If should stop returns false, check if we should notify of this event
864     virtual bool
865     DoShouldNotify (Event *event_ptr)
866     {
867         ThreadSP thread_sp (m_thread_wp.lock());
868         if (thread_sp)
869         {
870             bool should_notify = thread_sp->GetProcess()->GetUnixSignals().GetShouldNotify (m_value);
871             if (should_notify)
872             {
873                 StreamString strm;
874                 strm.Printf ("thread %d received signal: %s",
875                              thread_sp->GetIndexID(),
876                              thread_sp->GetProcess()->GetUnixSignals().GetSignalAsCString (m_value));
877                 Process::ProcessEventData::AddRestartedReason(event_ptr, strm.GetData());
878             }
879             return should_notify;
880         }
881         return true;
882     }
883 
884 
885     virtual void
886     WillResume (lldb::StateType resume_state)
887     {
888         ThreadSP thread_sp (m_thread_wp.lock());
889         if (thread_sp)
890         {
891             if (thread_sp->GetProcess()->GetUnixSignals().GetShouldSuppress(m_value) == false)
892                 thread_sp->SetResumeSignal(m_value);
893         }
894     }
895 
896     virtual const char *
897     GetDescription ()
898     {
899         if (m_description.empty())
900         {
901             ThreadSP thread_sp (m_thread_wp.lock());
902             if (thread_sp)
903             {
904                 StreamString strm;
905                 const char *signal_name = thread_sp->GetProcess()->GetUnixSignals().GetSignalAsCString (m_value);
906                 if (signal_name)
907                     strm.Printf("signal %s", signal_name);
908                 else
909                     strm.Printf("signal %" PRIi64, m_value);
910                 m_description.swap (strm.GetString());
911             }
912         }
913         return m_description.c_str();
914     }
915 };
916 
917 //----------------------------------------------------------------------
918 // StopInfoTrace
919 //----------------------------------------------------------------------
920 
921 class StopInfoTrace : public StopInfo
922 {
923 public:
924 
925     StopInfoTrace (Thread &thread) :
926         StopInfo (thread, LLDB_INVALID_UID)
927     {
928     }
929 
930     virtual ~StopInfoTrace ()
931     {
932     }
933 
934     virtual StopReason
935     GetStopReason () const
936     {
937         return eStopReasonTrace;
938     }
939 
940     virtual const char *
941     GetDescription ()
942     {
943         if (m_description.empty())
944         return "trace";
945         else
946             return m_description.c_str();
947     }
948 };
949 
950 
951 //----------------------------------------------------------------------
952 // StopInfoException
953 //----------------------------------------------------------------------
954 
955 class StopInfoException : public StopInfo
956 {
957 public:
958 
959     StopInfoException (Thread &thread, const char *description) :
960         StopInfo (thread, LLDB_INVALID_UID)
961     {
962         if (description)
963             SetDescription (description);
964     }
965 
966     virtual
967     ~StopInfoException ()
968     {
969     }
970 
971     virtual StopReason
972     GetStopReason () const
973     {
974         return eStopReasonException;
975     }
976 
977     virtual const char *
978     GetDescription ()
979     {
980         if (m_description.empty())
981             return "exception";
982         else
983             return m_description.c_str();
984     }
985 };
986 
987 
988 //----------------------------------------------------------------------
989 // StopInfoThreadPlan
990 //----------------------------------------------------------------------
991 
992 class StopInfoThreadPlan : public StopInfo
993 {
994 public:
995 
996     StopInfoThreadPlan (ThreadPlanSP &plan_sp, ValueObjectSP &return_valobj_sp) :
997         StopInfo (plan_sp->GetThread(), LLDB_INVALID_UID),
998         m_plan_sp (plan_sp),
999         m_return_valobj_sp (return_valobj_sp)
1000     {
1001     }
1002 
1003     virtual ~StopInfoThreadPlan ()
1004     {
1005     }
1006 
1007     virtual StopReason
1008     GetStopReason () const
1009     {
1010         return eStopReasonPlanComplete;
1011     }
1012 
1013     virtual const char *
1014     GetDescription ()
1015     {
1016         if (m_description.empty())
1017         {
1018             StreamString strm;
1019             m_plan_sp->GetDescription (&strm, eDescriptionLevelBrief);
1020             m_description.swap (strm.GetString());
1021         }
1022         return m_description.c_str();
1023     }
1024 
1025     ValueObjectSP
1026     GetReturnValueObject()
1027     {
1028         return m_return_valobj_sp;
1029     }
1030 
1031 protected:
1032     virtual bool
1033     ShouldStop (Event *event_ptr)
1034     {
1035         if (m_plan_sp)
1036             return m_plan_sp->ShouldStop(event_ptr);
1037         else
1038             return StopInfo::ShouldStop(event_ptr);
1039     }
1040 
1041 private:
1042     ThreadPlanSP m_plan_sp;
1043     ValueObjectSP m_return_valobj_sp;
1044 };
1045 
1046 class StopInfoExec : public StopInfo
1047 {
1048 public:
1049 
1050     StopInfoExec (Thread &thread) :
1051         StopInfo (thread, LLDB_INVALID_UID),
1052         m_performed_action (false)
1053     {
1054     }
1055 
1056     virtual
1057     ~StopInfoExec ()
1058     {
1059     }
1060 
1061     virtual StopReason
1062     GetStopReason () const
1063     {
1064         return eStopReasonExec;
1065     }
1066 
1067     virtual const char *
1068     GetDescription ()
1069     {
1070         return "exec";
1071     }
1072 protected:
1073 
1074     virtual void
1075     PerformAction (Event *event_ptr)
1076     {
1077         // Only perform the action once
1078         if (m_performed_action)
1079             return;
1080         m_performed_action = true;
1081         ThreadSP thread_sp (m_thread_wp.lock());
1082         if (thread_sp)
1083             thread_sp->GetProcess()->DidExec();
1084     }
1085 
1086     bool m_performed_action;
1087 };
1088 
1089 } // namespace lldb_private
1090 
1091 StopInfoSP
1092 StopInfo::CreateStopReasonWithBreakpointSiteID (Thread &thread, break_id_t break_id)
1093 {
1094     return StopInfoSP (new StopInfoBreakpoint (thread, break_id));
1095 }
1096 
1097 StopInfoSP
1098 StopInfo::CreateStopReasonWithBreakpointSiteID (Thread &thread, break_id_t break_id, bool should_stop)
1099 {
1100     return StopInfoSP (new StopInfoBreakpoint (thread, break_id, should_stop));
1101 }
1102 
1103 StopInfoSP
1104 StopInfo::CreateStopReasonWithWatchpointID (Thread &thread, break_id_t watch_id)
1105 {
1106     return StopInfoSP (new StopInfoWatchpoint (thread, watch_id));
1107 }
1108 
1109 StopInfoSP
1110 StopInfo::CreateStopReasonWithSignal (Thread &thread, int signo)
1111 {
1112     return StopInfoSP (new StopInfoUnixSignal (thread, signo));
1113 }
1114 
1115 StopInfoSP
1116 StopInfo::CreateStopReasonToTrace (Thread &thread)
1117 {
1118     return StopInfoSP (new StopInfoTrace (thread));
1119 }
1120 
1121 StopInfoSP
1122 StopInfo::CreateStopReasonWithPlan (ThreadPlanSP &plan_sp, ValueObjectSP return_valobj_sp)
1123 {
1124     return StopInfoSP (new StopInfoThreadPlan (plan_sp, return_valobj_sp));
1125 }
1126 
1127 StopInfoSP
1128 StopInfo::CreateStopReasonWithException (Thread &thread, const char *description)
1129 {
1130     return StopInfoSP (new StopInfoException (thread, description));
1131 }
1132 
1133 StopInfoSP
1134 StopInfo::CreateStopReasonWithExec (Thread &thread)
1135 {
1136     return StopInfoSP (new StopInfoExec (thread));
1137 }
1138 
1139 ValueObjectSP
1140 StopInfo::GetReturnValueObject(StopInfoSP &stop_info_sp)
1141 {
1142     if (stop_info_sp && stop_info_sp->GetStopReason() == eStopReasonPlanComplete)
1143     {
1144         StopInfoThreadPlan *plan_stop_info = static_cast<StopInfoThreadPlan *>(stop_info_sp.get());
1145         return plan_stop_info->GetReturnValueObject();
1146     }
1147     else
1148         return ValueObjectSP();
1149 }
1150