1 //===-- BreakpointLocation.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 // C Includes
13 // C++ Includes
14 #include <string>
15 
16 // Other libraries and framework includes
17 // Project includes
18 #include "lldb/lldb-private-log.h"
19 #include "lldb/Breakpoint/BreakpointLocation.h"
20 #include "lldb/Breakpoint/BreakpointID.h"
21 #include "lldb/Breakpoint/StoppointCallbackContext.h"
22 #include "lldb/Core/Debugger.h"
23 #include "lldb/Core/Log.h"
24 #include "lldb/Core/Module.h"
25 #include "lldb/Core/StreamString.h"
26 #include "lldb/Symbol/CompileUnit.h"
27 #include "lldb/Symbol/Symbol.h"
28 #include "lldb/Target/Target.h"
29 #include "lldb/Target/Process.h"
30 #include "lldb/Target/Thread.h"
31 #include "lldb/Target/ThreadSpec.h"
32 
33 using namespace lldb;
34 using namespace lldb_private;
35 
36 BreakpointLocation::BreakpointLocation
37 (
38     break_id_t loc_id,
39     Breakpoint &owner,
40     const Address &addr,
41     lldb::tid_t tid,
42     bool hardware,
43     bool check_for_resolver
44 ) :
45     StoppointLocation (loc_id, addr.GetOpcodeLoadAddress(&owner.GetTarget()), hardware),
46     m_being_created(true),
47     m_should_resolve_indirect_functions (false),
48     m_is_reexported (false),
49     m_is_indirect (false),
50     m_address (addr),
51     m_owner (owner),
52     m_options_ap (),
53     m_bp_site_sp (),
54     m_condition_mutex ()
55 {
56     if (check_for_resolver)
57     {
58         Symbol *symbol = m_address.CalculateSymbolContextSymbol();
59         if (symbol && symbol->IsIndirect())
60         {
61             SetShouldResolveIndirectFunctions (true);
62         }
63     }
64 
65     SetThreadID (tid);
66     m_being_created = false;
67 }
68 
69 BreakpointLocation::~BreakpointLocation()
70 {
71     ClearBreakpointSite();
72 }
73 
74 lldb::addr_t
75 BreakpointLocation::GetLoadAddress () const
76 {
77     return m_address.GetOpcodeLoadAddress (&m_owner.GetTarget());
78 }
79 
80 Address &
81 BreakpointLocation::GetAddress ()
82 {
83     return m_address;
84 }
85 
86 Breakpoint &
87 BreakpointLocation::GetBreakpoint ()
88 {
89     return m_owner;
90 }
91 
92 bool
93 BreakpointLocation::IsEnabled () const
94 {
95     if (!m_owner.IsEnabled())
96         return false;
97     else if (m_options_ap.get() != NULL)
98         return m_options_ap->IsEnabled();
99     else
100         return true;
101 }
102 
103 void
104 BreakpointLocation::SetEnabled (bool enabled)
105 {
106     GetLocationOptions()->SetEnabled(enabled);
107     if (enabled)
108     {
109         ResolveBreakpointSite();
110     }
111     else
112     {
113         ClearBreakpointSite();
114     }
115     SendBreakpointLocationChangedEvent (enabled ? eBreakpointEventTypeEnabled : eBreakpointEventTypeDisabled);
116 }
117 
118 void
119 BreakpointLocation::SetThreadID (lldb::tid_t thread_id)
120 {
121     if (thread_id != LLDB_INVALID_THREAD_ID)
122         GetLocationOptions()->SetThreadID(thread_id);
123     else
124     {
125         // If we're resetting this to an invalid thread id, then
126         // don't make an options pointer just to do that.
127         if (m_options_ap.get() != NULL)
128             m_options_ap->SetThreadID (thread_id);
129     }
130     SendBreakpointLocationChangedEvent (eBreakpointEventTypeThreadChanged);
131 }
132 
133 lldb::tid_t
134 BreakpointLocation::GetThreadID ()
135 {
136     if (GetOptionsNoCreate()->GetThreadSpecNoCreate())
137         return GetOptionsNoCreate()->GetThreadSpecNoCreate()->GetTID();
138     else
139         return LLDB_INVALID_THREAD_ID;
140 }
141 
142 void
143 BreakpointLocation::SetThreadIndex (uint32_t index)
144 {
145     if (index != 0)
146         GetLocationOptions()->GetThreadSpec()->SetIndex(index);
147     else
148     {
149         // If we're resetting this to an invalid thread id, then
150         // don't make an options pointer just to do that.
151         if (m_options_ap.get() != NULL)
152             m_options_ap->GetThreadSpec()->SetIndex(index);
153     }
154     SendBreakpointLocationChangedEvent (eBreakpointEventTypeThreadChanged);
155 
156 }
157 
158 uint32_t
159 BreakpointLocation::GetThreadIndex() const
160 {
161     if (GetOptionsNoCreate()->GetThreadSpecNoCreate())
162         return GetOptionsNoCreate()->GetThreadSpecNoCreate()->GetIndex();
163     else
164         return 0;
165 }
166 
167 void
168 BreakpointLocation::SetThreadName (const char *thread_name)
169 {
170     if (thread_name != NULL)
171         GetLocationOptions()->GetThreadSpec()->SetName(thread_name);
172     else
173     {
174         // If we're resetting this to an invalid thread id, then
175         // don't make an options pointer just to do that.
176         if (m_options_ap.get() != NULL)
177             m_options_ap->GetThreadSpec()->SetName(thread_name);
178     }
179     SendBreakpointLocationChangedEvent (eBreakpointEventTypeThreadChanged);
180 }
181 
182 const char *
183 BreakpointLocation::GetThreadName () const
184 {
185     if (GetOptionsNoCreate()->GetThreadSpecNoCreate())
186         return GetOptionsNoCreate()->GetThreadSpecNoCreate()->GetName();
187     else
188         return NULL;
189 }
190 
191 void
192 BreakpointLocation::SetQueueName (const char *queue_name)
193 {
194     if (queue_name != NULL)
195         GetLocationOptions()->GetThreadSpec()->SetQueueName(queue_name);
196     else
197     {
198         // If we're resetting this to an invalid thread id, then
199         // don't make an options pointer just to do that.
200         if (m_options_ap.get() != NULL)
201             m_options_ap->GetThreadSpec()->SetQueueName(queue_name);
202     }
203     SendBreakpointLocationChangedEvent (eBreakpointEventTypeThreadChanged);
204 }
205 
206 const char *
207 BreakpointLocation::GetQueueName () const
208 {
209     if (GetOptionsNoCreate()->GetThreadSpecNoCreate())
210         return GetOptionsNoCreate()->GetThreadSpecNoCreate()->GetQueueName();
211     else
212         return NULL;
213 }
214 
215 bool
216 BreakpointLocation::InvokeCallback (StoppointCallbackContext *context)
217 {
218     if (m_options_ap.get() != NULL && m_options_ap->HasCallback())
219         return m_options_ap->InvokeCallback (context, m_owner.GetID(), GetID());
220     else
221         return m_owner.InvokeCallback (context, GetID());
222 }
223 
224 void
225 BreakpointLocation::SetCallback (BreakpointHitCallback callback, void *baton,
226                  bool is_synchronous)
227 {
228     // The default "Baton" class will keep a copy of "baton" and won't free
229     // or delete it when it goes goes out of scope.
230     GetLocationOptions()->SetCallback(callback, BatonSP (new Baton(baton)), is_synchronous);
231     SendBreakpointLocationChangedEvent (eBreakpointEventTypeCommandChanged);
232 }
233 
234 void
235 BreakpointLocation::SetCallback (BreakpointHitCallback callback, const BatonSP &baton_sp,
236                  bool is_synchronous)
237 {
238     GetLocationOptions()->SetCallback (callback, baton_sp, is_synchronous);
239     SendBreakpointLocationChangedEvent (eBreakpointEventTypeCommandChanged);
240 }
241 
242 
243 void
244 BreakpointLocation::ClearCallback ()
245 {
246     GetLocationOptions()->ClearCallback();
247 }
248 
249 void
250 BreakpointLocation::SetCondition (const char *condition)
251 {
252     GetLocationOptions()->SetCondition (condition);
253     SendBreakpointLocationChangedEvent (eBreakpointEventTypeConditionChanged);
254 }
255 
256 const char *
257 BreakpointLocation::GetConditionText (size_t *hash) const
258 {
259     return GetOptionsNoCreate()->GetConditionText(hash);
260 }
261 
262 bool
263 BreakpointLocation::ConditionSaysStop (ExecutionContext &exe_ctx, Error &error)
264 {
265     Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_BREAKPOINTS);
266 
267     Mutex::Locker evaluation_locker(m_condition_mutex);
268 
269     size_t condition_hash;
270     const char *condition_text = GetConditionText(&condition_hash);
271 
272     if (!condition_text)
273     {
274         m_user_expression_sp.reset();
275         return false;
276     }
277 
278     if (condition_hash != m_condition_hash ||
279         !m_user_expression_sp ||
280         !m_user_expression_sp->MatchesContext(exe_ctx))
281     {
282         m_user_expression_sp.reset(new ClangUserExpression(condition_text,
283                                                            NULL,
284                                                            lldb::eLanguageTypeUnknown,
285                                                            ClangUserExpression::eResultTypeAny));
286 
287         StreamString errors;
288 
289         if (!m_user_expression_sp->Parse(errors,
290                                          exe_ctx,
291                                          eExecutionPolicyOnlyWhenNeeded,
292                                          true,
293                                          false))
294         {
295             error.SetErrorStringWithFormat("Couldn't parse conditional expression:\n%s",
296                                            errors.GetData());
297             m_user_expression_sp.reset();
298             return false;
299         }
300 
301         m_condition_hash = condition_hash;
302     }
303 
304     // We need to make sure the user sees any parse errors in their condition, so we'll hook the
305     // constructor errors up to the debugger's Async I/O.
306 
307     ValueObjectSP result_value_sp;
308 
309     EvaluateExpressionOptions options;
310     options.SetUnwindOnError(true);
311     options.SetIgnoreBreakpoints(true);
312     options.SetTryAllThreads(true);
313 
314     Error expr_error;
315 
316     StreamString execution_errors;
317 
318     ClangExpressionVariableSP result_variable_sp;
319 
320     ExpressionResults result_code =
321     m_user_expression_sp->Execute(execution_errors,
322                                   exe_ctx,
323                                   options,
324                                   m_user_expression_sp,
325                                   result_variable_sp);
326 
327     bool ret;
328 
329     if (result_code == eExpressionCompleted)
330     {
331         if (!result_variable_sp)
332         {
333             error.SetErrorString("Expression did not return a result");
334             return false;
335         }
336 
337         result_value_sp = result_variable_sp->GetValueObject();
338 
339         if (result_value_sp)
340         {
341             Scalar scalar_value;
342             if (result_value_sp->ResolveValue (scalar_value))
343             {
344                 if (scalar_value.ULongLong(1) == 0)
345                     ret = false;
346                 else
347                     ret = true;
348                 if (log)
349                     log->Printf("Condition successfully evaluated, result is %s.\n",
350                                 ret ? "true" : "false");
351             }
352             else
353             {
354                 ret = false;
355                 error.SetErrorString("Failed to get an integer result from the expression");
356             }
357         }
358         else
359         {
360             ret = false;
361             error.SetErrorString("Failed to get any result from the expression");
362         }
363     }
364     else
365     {
366         ret = false;
367         error.SetErrorStringWithFormat("Couldn't execute expression:\n%s", execution_errors.GetData());
368     }
369 
370     return ret;
371 }
372 
373 uint32_t
374 BreakpointLocation::GetIgnoreCount ()
375 {
376     return GetOptionsNoCreate()->GetIgnoreCount();
377 }
378 
379 void
380 BreakpointLocation::SetIgnoreCount (uint32_t n)
381 {
382     GetLocationOptions()->SetIgnoreCount(n);
383     SendBreakpointLocationChangedEvent (eBreakpointEventTypeIgnoreChanged);
384 }
385 
386 void
387 BreakpointLocation::DecrementIgnoreCount()
388 {
389     if (m_options_ap.get() != NULL)
390     {
391         uint32_t loc_ignore = m_options_ap->GetIgnoreCount();
392         if (loc_ignore != 0)
393             m_options_ap->SetIgnoreCount(loc_ignore - 1);
394     }
395 }
396 
397 bool
398 BreakpointLocation::IgnoreCountShouldStop()
399 {
400     if (m_options_ap.get() != NULL)
401     {
402         uint32_t loc_ignore = m_options_ap->GetIgnoreCount();
403         if (loc_ignore != 0)
404         {
405             m_owner.DecrementIgnoreCount();
406             DecrementIgnoreCount();          // Have to decrement our owners' ignore count, since it won't get a
407                                              // chance to.
408             return false;
409         }
410     }
411     return true;
412 }
413 
414 const BreakpointOptions *
415 BreakpointLocation::GetOptionsNoCreate () const
416 {
417     if (m_options_ap.get() != NULL)
418         return m_options_ap.get();
419     else
420         return m_owner.GetOptions ();
421 }
422 
423 BreakpointOptions *
424 BreakpointLocation::GetLocationOptions ()
425 {
426     // If we make the copy we don't copy the callbacks because that is potentially
427     // expensive and we don't want to do that for the simple case where someone is
428     // just disabling the location.
429     if (m_options_ap.get() == NULL)
430         m_options_ap.reset(BreakpointOptions::CopyOptionsNoCallback(*m_owner.GetOptions ()));
431 
432     return m_options_ap.get();
433 }
434 
435 bool
436 BreakpointLocation::ValidForThisThread (Thread *thread)
437 {
438     return thread->MatchesSpec(GetOptionsNoCreate()->GetThreadSpecNoCreate());
439 }
440 
441 // RETURNS - true if we should stop at this breakpoint, false if we
442 // should continue.  Note, we don't check the thread spec for the breakpoint
443 // here, since if the breakpoint is not for this thread, then the event won't
444 // even get reported, so the check is redundant.
445 
446 bool
447 BreakpointLocation::ShouldStop (StoppointCallbackContext *context)
448 {
449     bool should_stop = true;
450     Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_BREAKPOINTS);
451 
452     // Do this first, if a location is disabled, it shouldn't increment its hit count.
453     if (!IsEnabled())
454         return false;
455 
456     if (!IgnoreCountShouldStop())
457         return false;
458 
459     if (!m_owner.IgnoreCountShouldStop())
460         return false;
461 
462     // We only run synchronous callbacks in ShouldStop:
463     context->is_synchronous = true;
464     should_stop = InvokeCallback (context);
465 
466     if (log)
467     {
468         StreamString s;
469         GetDescription (&s, lldb::eDescriptionLevelVerbose);
470         log->Printf ("Hit breakpoint location: %s, %s.\n", s.GetData(), should_stop ? "stopping" : "continuing");
471     }
472 
473     return should_stop;
474 }
475 
476 void
477 BreakpointLocation::BumpHitCount()
478 {
479     if (IsEnabled())
480     {
481         // Step our hit count, and also step the hit count of the owner.
482         IncrementHitCount();
483         m_owner.IncrementHitCount();
484     }
485 }
486 
487 void
488 BreakpointLocation::UndoBumpHitCount()
489 {
490     if (IsEnabled())
491     {
492         // Step our hit count, and also step the hit count of the owner.
493         DecrementHitCount();
494         m_owner.DecrementHitCount();
495     }
496 }
497 
498 bool
499 BreakpointLocation::IsResolved () const
500 {
501     return m_bp_site_sp.get() != NULL;
502 }
503 
504 lldb::BreakpointSiteSP
505 BreakpointLocation::GetBreakpointSite() const
506 {
507     return m_bp_site_sp;
508 }
509 
510 bool
511 BreakpointLocation::ResolveBreakpointSite ()
512 {
513     if (m_bp_site_sp)
514         return true;
515 
516     Process *process = m_owner.GetTarget().GetProcessSP().get();
517     if (process == NULL)
518         return false;
519 
520     lldb::break_id_t new_id = process->CreateBreakpointSite (shared_from_this(), m_owner.IsHardware());
521 
522     if (new_id == LLDB_INVALID_BREAK_ID)
523     {
524         Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_BREAKPOINTS);
525         if (log)
526             log->Warning ("Tried to add breakpoint site at 0x%" PRIx64 " but it was already present.\n",
527                           m_address.GetOpcodeLoadAddress (&m_owner.GetTarget()));
528         return false;
529     }
530 
531     return true;
532 }
533 
534 bool
535 BreakpointLocation::SetBreakpointSite (BreakpointSiteSP& bp_site_sp)
536 {
537     m_bp_site_sp = bp_site_sp;
538     return true;
539 }
540 
541 bool
542 BreakpointLocation::ClearBreakpointSite ()
543 {
544     if (m_bp_site_sp.get())
545     {
546         ProcessSP process_sp(m_owner.GetTarget().GetProcessSP());
547         // If the process exists, get it to remove the owner, it will remove the physical implementation
548         // of the breakpoint as well if there are no more owners.  Otherwise just remove this owner.
549         if (process_sp)
550             process_sp->RemoveOwnerFromBreakpointSite (GetBreakpoint().GetID(),
551                                                                            GetID(), m_bp_site_sp);
552         else
553             m_bp_site_sp->RemoveOwner(GetBreakpoint().GetID(), GetID());
554 
555         m_bp_site_sp.reset();
556         return true;
557     }
558     return false;
559 }
560 
561 void
562 BreakpointLocation::GetDescription (Stream *s, lldb::DescriptionLevel level)
563 {
564     SymbolContext sc;
565 
566     // If the description level is "initial" then the breakpoint is printing out our initial state,
567     // and we should let it decide how it wants to print our label.
568     if (level != eDescriptionLevelInitial)
569     {
570         s->Indent();
571         BreakpointID::GetCanonicalReference(s, m_owner.GetID(), GetID());
572     }
573 
574     if (level == lldb::eDescriptionLevelBrief)
575         return;
576 
577     if (level != eDescriptionLevelInitial)
578         s->PutCString(": ");
579 
580     if (level == lldb::eDescriptionLevelVerbose)
581         s->IndentMore();
582 
583     if (m_address.IsSectionOffset())
584     {
585         m_address.CalculateSymbolContext(&sc);
586 
587         if (level == lldb::eDescriptionLevelFull || level == eDescriptionLevelInitial)
588         {
589             if (IsReExported())
590                 s->PutCString ("re-exported target = ");
591             else
592                 s->PutCString("where = ");
593             sc.DumpStopContext (s, m_owner.GetTarget().GetProcessSP().get(), m_address, false, true, false, true, true);
594         }
595         else
596         {
597             if (sc.module_sp)
598             {
599                 s->EOL();
600                 s->Indent("module = ");
601                 sc.module_sp->GetFileSpec().Dump (s);
602             }
603 
604             if (sc.comp_unit != NULL)
605             {
606                 s->EOL();
607                 s->Indent("compile unit = ");
608                 static_cast<FileSpec*>(sc.comp_unit)->GetFilename().Dump (s);
609 
610                 if (sc.function != NULL)
611                 {
612                     s->EOL();
613                     s->Indent("function = ");
614                     s->PutCString (sc.function->GetMangled().GetName().AsCString("<unknown>"));
615                 }
616 
617                 if (sc.line_entry.line > 0)
618                 {
619                     s->EOL();
620                     s->Indent("location = ");
621                     sc.line_entry.DumpStopContext (s, true);
622                 }
623 
624             }
625             else
626             {
627                 // If we don't have a comp unit, see if we have a symbol we can print.
628                 if (sc.symbol)
629                 {
630                     s->EOL();
631                     if (IsReExported())
632                         s->Indent ("re-exported target = ");
633                     else
634                         s->Indent("symbol = ");
635                     s->PutCString(sc.symbol->GetMangled().GetName().AsCString("<unknown>"));
636                 }
637             }
638         }
639     }
640 
641     if (level == lldb::eDescriptionLevelVerbose)
642     {
643         s->EOL();
644         s->Indent();
645     }
646 
647     if (m_address.IsSectionOffset() && (level == eDescriptionLevelFull || level == eDescriptionLevelInitial))
648         s->Printf (", ");
649     s->Printf ("address = ");
650 
651     ExecutionContextScope *exe_scope = NULL;
652     Target *target = &m_owner.GetTarget();
653     if (target)
654         exe_scope = target->GetProcessSP().get();
655     if (exe_scope == NULL)
656         exe_scope = target;
657 
658     if (level == eDescriptionLevelInitial)
659         m_address.Dump(s, exe_scope, Address::DumpStyleLoadAddress, Address::DumpStyleFileAddress);
660     else
661         m_address.Dump(s, exe_scope, Address::DumpStyleLoadAddress, Address::DumpStyleModuleWithFileAddress);
662 
663     if (IsIndirect() && m_bp_site_sp)
664     {
665         Address resolved_address;
666         resolved_address.SetLoadAddress(m_bp_site_sp->GetLoadAddress(), target);
667         Symbol *resolved_symbol = resolved_address.CalculateSymbolContextSymbol();
668         if (resolved_symbol)
669         {
670             if (level == eDescriptionLevelFull || level == eDescriptionLevelInitial)
671                 s->Printf (", ");
672             else if (level == lldb::eDescriptionLevelVerbose)
673             {
674                 s->EOL();
675                 s->Indent();
676             }
677             s->Printf ("indirect target = %s", resolved_symbol->GetName().GetCString());
678         }
679     }
680 
681     if (level == lldb::eDescriptionLevelVerbose)
682     {
683         s->EOL();
684         s->Indent();
685         s->Printf("resolved = %s\n", IsResolved() ? "true" : "false");
686 
687         s->Indent();
688         s->Printf ("hit count = %-4u\n", GetHitCount());
689 
690         if (m_options_ap.get())
691         {
692             s->Indent();
693             m_options_ap->GetDescription (s, level);
694             s->EOL();
695         }
696         s->IndentLess();
697     }
698     else if (level != eDescriptionLevelInitial)
699     {
700         s->Printf(", %sresolved, hit count = %u ",
701                   (IsResolved() ? "" : "un"),
702                   GetHitCount());
703         if (m_options_ap.get())
704         {
705             m_options_ap->GetDescription (s, level);
706         }
707     }
708 }
709 
710 void
711 BreakpointLocation::Dump(Stream *s) const
712 {
713     if (s == NULL)
714         return;
715 
716     s->Printf("BreakpointLocation %u: tid = %4.4" PRIx64 "  load addr = 0x%8.8" PRIx64 "  state = %s  type = %s breakpoint  "
717               "hw_index = %i  hit_count = %-4u  ignore_count = %-4u",
718               GetID(),
719               GetOptionsNoCreate()->GetThreadSpecNoCreate()->GetTID(),
720               (uint64_t) m_address.GetOpcodeLoadAddress (&m_owner.GetTarget()),
721               (m_options_ap.get() ? m_options_ap->IsEnabled() : m_owner.IsEnabled()) ? "enabled " : "disabled",
722               IsHardware() ? "hardware" : "software",
723               GetHardwareIndex(),
724               GetHitCount(),
725               GetOptionsNoCreate()->GetIgnoreCount());
726 }
727 
728 void
729 BreakpointLocation::SendBreakpointLocationChangedEvent (lldb::BreakpointEventType eventKind)
730 {
731     if (!m_being_created
732         && !m_owner.IsInternal()
733         && m_owner.GetTarget().EventTypeHasListeners(Target::eBroadcastBitBreakpointChanged))
734     {
735         Breakpoint::BreakpointEventData *data = new Breakpoint::BreakpointEventData (eventKind,
736                                                                                      m_owner.shared_from_this());
737         data->GetBreakpointLocationCollection().Add (shared_from_this());
738         m_owner.GetTarget().BroadcastEvent (Target::eBroadcastBitBreakpointChanged, data);
739     }
740 }
741 
742 void
743 BreakpointLocation::SwapLocation (BreakpointLocationSP swap_from)
744 {
745     m_address = swap_from->m_address;
746     m_should_resolve_indirect_functions = swap_from->m_should_resolve_indirect_functions;
747     m_is_reexported = swap_from->m_is_reexported;
748     m_is_indirect = swap_from->m_is_indirect;
749     m_user_expression_sp.reset();
750 }
751