1 //===-- ExecutionContext.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 // C Includes
11 // C++ Includes
12 // Other libraries and framework includes
13 // Project includes
14 #include "lldb/Target/ExecutionContext.h"
15 #include "lldb/Target/ExecutionContextScope.h"
16 #include "lldb/Target/Process.h"
17 #include "lldb/Target/StackFrame.h"
18 #include "lldb/Target/Target.h"
19 #include "lldb/Target/Thread.h"
20 #include "lldb/Utility/State.h"
21 
22 using namespace lldb_private;
23 
24 ExecutionContext::ExecutionContext()
25     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {}
26 
27 ExecutionContext::ExecutionContext(const ExecutionContext &rhs)
28     : m_target_sp(rhs.m_target_sp), m_process_sp(rhs.m_process_sp),
29       m_thread_sp(rhs.m_thread_sp), m_frame_sp(rhs.m_frame_sp) {}
30 
31 ExecutionContext::ExecutionContext(const lldb::TargetSP &target_sp,
32                                    bool get_process)
33     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
34   if (target_sp)
35     SetContext(target_sp, get_process);
36 }
37 
38 ExecutionContext::ExecutionContext(const lldb::ProcessSP &process_sp)
39     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
40   if (process_sp)
41     SetContext(process_sp);
42 }
43 
44 ExecutionContext::ExecutionContext(const lldb::ThreadSP &thread_sp)
45     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
46   if (thread_sp)
47     SetContext(thread_sp);
48 }
49 
50 ExecutionContext::ExecutionContext(const lldb::StackFrameSP &frame_sp)
51     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
52   if (frame_sp)
53     SetContext(frame_sp);
54 }
55 
56 ExecutionContext::ExecutionContext(const lldb::TargetWP &target_wp,
57                                    bool get_process)
58     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
59   lldb::TargetSP target_sp(target_wp.lock());
60   if (target_sp)
61     SetContext(target_sp, get_process);
62 }
63 
64 ExecutionContext::ExecutionContext(const lldb::ProcessWP &process_wp)
65     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
66   lldb::ProcessSP process_sp(process_wp.lock());
67   if (process_sp)
68     SetContext(process_sp);
69 }
70 
71 ExecutionContext::ExecutionContext(const lldb::ThreadWP &thread_wp)
72     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
73   lldb::ThreadSP thread_sp(thread_wp.lock());
74   if (thread_sp)
75     SetContext(thread_sp);
76 }
77 
78 ExecutionContext::ExecutionContext(const lldb::StackFrameWP &frame_wp)
79     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
80   lldb::StackFrameSP frame_sp(frame_wp.lock());
81   if (frame_sp)
82     SetContext(frame_sp);
83 }
84 
85 ExecutionContext::ExecutionContext(Target *t,
86                                    bool fill_current_process_thread_frame)
87     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
88   if (t) {
89     m_target_sp = t->shared_from_this();
90     if (fill_current_process_thread_frame) {
91       m_process_sp = t->GetProcessSP();
92       if (m_process_sp) {
93         m_thread_sp = m_process_sp->GetThreadList().GetSelectedThread();
94         if (m_thread_sp)
95           m_frame_sp = m_thread_sp->GetSelectedFrame();
96       }
97     }
98   }
99 }
100 
101 ExecutionContext::ExecutionContext(Process *process, Thread *thread,
102                                    StackFrame *frame)
103     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
104   if (process) {
105     m_process_sp = process->shared_from_this();
106     m_target_sp = process->GetTarget().shared_from_this();
107   }
108   if (thread)
109     m_thread_sp = thread->shared_from_this();
110   if (frame)
111     m_frame_sp = frame->shared_from_this();
112 }
113 
114 ExecutionContext::ExecutionContext(const ExecutionContextRef &exe_ctx_ref)
115     : m_target_sp(exe_ctx_ref.GetTargetSP()),
116       m_process_sp(exe_ctx_ref.GetProcessSP()),
117       m_thread_sp(exe_ctx_ref.GetThreadSP()),
118       m_frame_sp(exe_ctx_ref.GetFrameSP()) {}
119 
120 ExecutionContext::ExecutionContext(const ExecutionContextRef *exe_ctx_ref_ptr,
121                                    bool thread_and_frame_only_if_stopped)
122     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
123   if (exe_ctx_ref_ptr) {
124     m_target_sp = exe_ctx_ref_ptr->GetTargetSP();
125     m_process_sp = exe_ctx_ref_ptr->GetProcessSP();
126     if (!thread_and_frame_only_if_stopped ||
127         (m_process_sp && StateIsStoppedState(m_process_sp->GetState(), true))) {
128       m_thread_sp = exe_ctx_ref_ptr->GetThreadSP();
129       m_frame_sp = exe_ctx_ref_ptr->GetFrameSP();
130     }
131   }
132 }
133 
134 ExecutionContext::ExecutionContext(const ExecutionContextRef *exe_ctx_ref_ptr,
135                                    std::unique_lock<std::recursive_mutex> &lock)
136     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
137   if (exe_ctx_ref_ptr) {
138     m_target_sp = exe_ctx_ref_ptr->GetTargetSP();
139     if (m_target_sp) {
140       lock = std::unique_lock<std::recursive_mutex>(m_target_sp->GetAPIMutex());
141 
142       m_process_sp = exe_ctx_ref_ptr->GetProcessSP();
143       m_thread_sp = exe_ctx_ref_ptr->GetThreadSP();
144       m_frame_sp = exe_ctx_ref_ptr->GetFrameSP();
145     }
146   }
147 }
148 
149 ExecutionContext::ExecutionContext(const ExecutionContextRef &exe_ctx_ref,
150                                    std::unique_lock<std::recursive_mutex> &lock)
151     : m_target_sp(exe_ctx_ref.GetTargetSP()), m_process_sp(), m_thread_sp(),
152       m_frame_sp() {
153   if (m_target_sp) {
154     lock = std::unique_lock<std::recursive_mutex>(m_target_sp->GetAPIMutex());
155 
156     m_process_sp = exe_ctx_ref.GetProcessSP();
157     m_thread_sp = exe_ctx_ref.GetThreadSP();
158     m_frame_sp = exe_ctx_ref.GetFrameSP();
159   }
160 }
161 
162 ExecutionContext::ExecutionContext(ExecutionContextScope *exe_scope_ptr)
163     : m_target_sp(), m_process_sp(), m_thread_sp(), m_frame_sp() {
164   if (exe_scope_ptr)
165     exe_scope_ptr->CalculateExecutionContext(*this);
166 }
167 
168 ExecutionContext::ExecutionContext(ExecutionContextScope &exe_scope_ref) {
169   exe_scope_ref.CalculateExecutionContext(*this);
170 }
171 
172 void ExecutionContext::Clear() {
173   m_target_sp.reset();
174   m_process_sp.reset();
175   m_thread_sp.reset();
176   m_frame_sp.reset();
177 }
178 
179 ExecutionContext::~ExecutionContext() = default;
180 
181 uint32_t ExecutionContext::GetAddressByteSize() const {
182   if (m_target_sp && m_target_sp->GetArchitecture().IsValid())
183     return m_target_sp->GetArchitecture().GetAddressByteSize();
184   if (m_process_sp)
185     return m_process_sp->GetAddressByteSize();
186   return sizeof(void *);
187 }
188 
189 lldb::ByteOrder ExecutionContext::GetByteOrder() const {
190   if (m_target_sp && m_target_sp->GetArchitecture().IsValid())
191     m_target_sp->GetArchitecture().GetByteOrder();
192   if (m_process_sp)
193     m_process_sp->GetByteOrder();
194   return endian::InlHostByteOrder();
195 }
196 
197 RegisterContext *ExecutionContext::GetRegisterContext() const {
198   if (m_frame_sp)
199     return m_frame_sp->GetRegisterContext().get();
200   else if (m_thread_sp)
201     return m_thread_sp->GetRegisterContext().get();
202   return nullptr;
203 }
204 
205 Target *ExecutionContext::GetTargetPtr() const {
206   if (m_target_sp)
207     return m_target_sp.get();
208   if (m_process_sp)
209     return &m_process_sp->GetTarget();
210   return nullptr;
211 }
212 
213 Process *ExecutionContext::GetProcessPtr() const {
214   if (m_process_sp)
215     return m_process_sp.get();
216   if (m_target_sp)
217     return m_target_sp->GetProcessSP().get();
218   return nullptr;
219 }
220 
221 ExecutionContextScope *ExecutionContext::GetBestExecutionContextScope() const {
222   if (m_frame_sp)
223     return m_frame_sp.get();
224   if (m_thread_sp)
225     return m_thread_sp.get();
226   if (m_process_sp)
227     return m_process_sp.get();
228   return m_target_sp.get();
229 }
230 
231 Target &ExecutionContext::GetTargetRef() const {
232 #if defined(LLDB_CONFIGURATION_DEBUG) || defined(LLDB_CONFIGURATION_RELEASE)
233   assert(m_target_sp);
234 #endif
235   return *m_target_sp;
236 }
237 
238 Process &ExecutionContext::GetProcessRef() const {
239 #if defined(LLDB_CONFIGURATION_DEBUG) || defined(LLDB_CONFIGURATION_RELEASE)
240   assert(m_process_sp);
241 #endif
242   return *m_process_sp;
243 }
244 
245 Thread &ExecutionContext::GetThreadRef() const {
246 #if defined(LLDB_CONFIGURATION_DEBUG) || defined(LLDB_CONFIGURATION_RELEASE)
247   assert(m_thread_sp);
248 #endif
249   return *m_thread_sp;
250 }
251 
252 StackFrame &ExecutionContext::GetFrameRef() const {
253 #if defined(LLDB_CONFIGURATION_DEBUG) || defined(LLDB_CONFIGURATION_RELEASE)
254   assert(m_frame_sp);
255 #endif
256   return *m_frame_sp;
257 }
258 
259 void ExecutionContext::SetTargetSP(const lldb::TargetSP &target_sp) {
260   m_target_sp = target_sp;
261 }
262 
263 void ExecutionContext::SetProcessSP(const lldb::ProcessSP &process_sp) {
264   m_process_sp = process_sp;
265 }
266 
267 void ExecutionContext::SetThreadSP(const lldb::ThreadSP &thread_sp) {
268   m_thread_sp = thread_sp;
269 }
270 
271 void ExecutionContext::SetFrameSP(const lldb::StackFrameSP &frame_sp) {
272   m_frame_sp = frame_sp;
273 }
274 
275 void ExecutionContext::SetTargetPtr(Target *target) {
276   if (target)
277     m_target_sp = target->shared_from_this();
278   else
279     m_target_sp.reset();
280 }
281 
282 void ExecutionContext::SetProcessPtr(Process *process) {
283   if (process)
284     m_process_sp = process->shared_from_this();
285   else
286     m_process_sp.reset();
287 }
288 
289 void ExecutionContext::SetThreadPtr(Thread *thread) {
290   if (thread)
291     m_thread_sp = thread->shared_from_this();
292   else
293     m_thread_sp.reset();
294 }
295 
296 void ExecutionContext::SetFramePtr(StackFrame *frame) {
297   if (frame)
298     m_frame_sp = frame->shared_from_this();
299   else
300     m_frame_sp.reset();
301 }
302 
303 void ExecutionContext::SetContext(const lldb::TargetSP &target_sp,
304                                   bool get_process) {
305   m_target_sp = target_sp;
306   if (get_process && target_sp)
307     m_process_sp = target_sp->GetProcessSP();
308   else
309     m_process_sp.reset();
310   m_thread_sp.reset();
311   m_frame_sp.reset();
312 }
313 
314 void ExecutionContext::SetContext(const lldb::ProcessSP &process_sp) {
315   m_process_sp = process_sp;
316   if (process_sp)
317     m_target_sp = process_sp->GetTarget().shared_from_this();
318   else
319     m_target_sp.reset();
320   m_thread_sp.reset();
321   m_frame_sp.reset();
322 }
323 
324 void ExecutionContext::SetContext(const lldb::ThreadSP &thread_sp) {
325   m_frame_sp.reset();
326   m_thread_sp = thread_sp;
327   if (thread_sp) {
328     m_process_sp = thread_sp->GetProcess();
329     if (m_process_sp)
330       m_target_sp = m_process_sp->GetTarget().shared_from_this();
331     else
332       m_target_sp.reset();
333   } else {
334     m_target_sp.reset();
335     m_process_sp.reset();
336   }
337 }
338 
339 void ExecutionContext::SetContext(const lldb::StackFrameSP &frame_sp) {
340   m_frame_sp = frame_sp;
341   if (frame_sp) {
342     m_thread_sp = frame_sp->CalculateThread();
343     if (m_thread_sp) {
344       m_process_sp = m_thread_sp->GetProcess();
345       if (m_process_sp)
346         m_target_sp = m_process_sp->GetTarget().shared_from_this();
347       else
348         m_target_sp.reset();
349     } else {
350       m_target_sp.reset();
351       m_process_sp.reset();
352     }
353   } else {
354     m_target_sp.reset();
355     m_process_sp.reset();
356     m_thread_sp.reset();
357   }
358 }
359 
360 ExecutionContext &ExecutionContext::operator=(const ExecutionContext &rhs) {
361   if (this != &rhs) {
362     m_target_sp = rhs.m_target_sp;
363     m_process_sp = rhs.m_process_sp;
364     m_thread_sp = rhs.m_thread_sp;
365     m_frame_sp = rhs.m_frame_sp;
366   }
367   return *this;
368 }
369 
370 bool ExecutionContext::operator==(const ExecutionContext &rhs) const {
371   // Check that the frame shared pointers match, or both are valid and their
372   // stack IDs match since sometimes we get new objects that represent the same
373   // frame within a thread.
374   if ((m_frame_sp == rhs.m_frame_sp) ||
375       (m_frame_sp && rhs.m_frame_sp &&
376        m_frame_sp->GetStackID() == rhs.m_frame_sp->GetStackID())) {
377     // Check that the thread shared pointers match, or both are valid and their
378     // thread IDs match since sometimes we get new objects that represent the
379     // same thread within a process.
380     if ((m_thread_sp == rhs.m_thread_sp) ||
381         (m_thread_sp && rhs.m_thread_sp &&
382          m_thread_sp->GetID() == rhs.m_thread_sp->GetID())) {
383       // Processes and targets don't change much
384       return m_process_sp == rhs.m_process_sp && m_target_sp == rhs.m_target_sp;
385     }
386   }
387   return false;
388 }
389 
390 bool ExecutionContext::operator!=(const ExecutionContext &rhs) const {
391   return !(*this == rhs);
392 }
393 
394 bool ExecutionContext::HasTargetScope() const {
395   return ((bool)m_target_sp && m_target_sp->IsValid());
396 }
397 
398 bool ExecutionContext::HasProcessScope() const {
399   return (HasTargetScope() && ((bool)m_process_sp && m_process_sp->IsValid()));
400 }
401 
402 bool ExecutionContext::HasThreadScope() const {
403   return (HasProcessScope() && ((bool)m_thread_sp && m_thread_sp->IsValid()));
404 }
405 
406 bool ExecutionContext::HasFrameScope() const {
407   return HasThreadScope() && m_frame_sp;
408 }
409 
410 ExecutionContextRef::ExecutionContextRef()
411     : m_target_wp(), m_process_wp(), m_thread_wp(),
412       m_tid(LLDB_INVALID_THREAD_ID), m_stack_id() {}
413 
414 ExecutionContextRef::ExecutionContextRef(const ExecutionContext *exe_ctx)
415     : m_target_wp(), m_process_wp(), m_thread_wp(),
416       m_tid(LLDB_INVALID_THREAD_ID), m_stack_id() {
417   if (exe_ctx)
418     *this = *exe_ctx;
419 }
420 
421 ExecutionContextRef::ExecutionContextRef(const ExecutionContext &exe_ctx)
422     : m_target_wp(), m_process_wp(), m_thread_wp(),
423       m_tid(LLDB_INVALID_THREAD_ID), m_stack_id() {
424   *this = exe_ctx;
425 }
426 
427 ExecutionContextRef::ExecutionContextRef(Target *target, bool adopt_selected)
428     : m_target_wp(), m_process_wp(), m_thread_wp(),
429       m_tid(LLDB_INVALID_THREAD_ID), m_stack_id() {
430   SetTargetPtr(target, adopt_selected);
431 }
432 
433 ExecutionContextRef::ExecutionContextRef(const ExecutionContextRef &rhs)
434     : m_target_wp(rhs.m_target_wp), m_process_wp(rhs.m_process_wp),
435       m_thread_wp(rhs.m_thread_wp), m_tid(rhs.m_tid),
436       m_stack_id(rhs.m_stack_id) {}
437 
438 ExecutionContextRef &ExecutionContextRef::
439 operator=(const ExecutionContextRef &rhs) {
440   if (this != &rhs) {
441     m_target_wp = rhs.m_target_wp;
442     m_process_wp = rhs.m_process_wp;
443     m_thread_wp = rhs.m_thread_wp;
444     m_tid = rhs.m_tid;
445     m_stack_id = rhs.m_stack_id;
446   }
447   return *this;
448 }
449 
450 ExecutionContextRef &ExecutionContextRef::
451 operator=(const ExecutionContext &exe_ctx) {
452   m_target_wp = exe_ctx.GetTargetSP();
453   m_process_wp = exe_ctx.GetProcessSP();
454   lldb::ThreadSP thread_sp(exe_ctx.GetThreadSP());
455   m_thread_wp = thread_sp;
456   if (thread_sp)
457     m_tid = thread_sp->GetID();
458   else
459     m_tid = LLDB_INVALID_THREAD_ID;
460   lldb::StackFrameSP frame_sp(exe_ctx.GetFrameSP());
461   if (frame_sp)
462     m_stack_id = frame_sp->GetStackID();
463   else
464     m_stack_id.Clear();
465   return *this;
466 }
467 
468 void ExecutionContextRef::Clear() {
469   m_target_wp.reset();
470   m_process_wp.reset();
471   ClearThread();
472   ClearFrame();
473 }
474 
475 ExecutionContextRef::~ExecutionContextRef() = default;
476 
477 void ExecutionContextRef::SetTargetSP(const lldb::TargetSP &target_sp) {
478   m_target_wp = target_sp;
479 }
480 
481 void ExecutionContextRef::SetProcessSP(const lldb::ProcessSP &process_sp) {
482   if (process_sp) {
483     m_process_wp = process_sp;
484     SetTargetSP(process_sp->GetTarget().shared_from_this());
485   } else {
486     m_process_wp.reset();
487     m_target_wp.reset();
488   }
489 }
490 
491 void ExecutionContextRef::SetThreadSP(const lldb::ThreadSP &thread_sp) {
492   if (thread_sp) {
493     m_thread_wp = thread_sp;
494     m_tid = thread_sp->GetID();
495     SetProcessSP(thread_sp->GetProcess());
496   } else {
497     ClearThread();
498     m_process_wp.reset();
499     m_target_wp.reset();
500   }
501 }
502 
503 void ExecutionContextRef::SetFrameSP(const lldb::StackFrameSP &frame_sp) {
504   if (frame_sp) {
505     m_stack_id = frame_sp->GetStackID();
506     SetThreadSP(frame_sp->GetThread());
507   } else {
508     ClearFrame();
509     ClearThread();
510     m_process_wp.reset();
511     m_target_wp.reset();
512   }
513 }
514 
515 void ExecutionContextRef::SetTargetPtr(Target *target, bool adopt_selected) {
516   Clear();
517   if (target) {
518     lldb::TargetSP target_sp(target->shared_from_this());
519     if (target_sp) {
520       m_target_wp = target_sp;
521       if (adopt_selected) {
522         lldb::ProcessSP process_sp(target_sp->GetProcessSP());
523         if (process_sp) {
524           m_process_wp = process_sp;
525           if (process_sp) {
526             // Only fill in the thread and frame if our process is stopped
527             // Don't just check the state, since we might be in the middle of
528             // resuming.
529             Process::StopLocker stop_locker;
530 
531             if (stop_locker.TryLock(&process_sp->GetRunLock()) &&
532                 StateIsStoppedState(process_sp->GetState(), true)) {
533               lldb::ThreadSP thread_sp(
534                   process_sp->GetThreadList().GetSelectedThread());
535               if (!thread_sp)
536                 thread_sp = process_sp->GetThreadList().GetThreadAtIndex(0);
537 
538               if (thread_sp) {
539                 SetThreadSP(thread_sp);
540                 lldb::StackFrameSP frame_sp(thread_sp->GetSelectedFrame());
541                 if (!frame_sp)
542                   frame_sp = thread_sp->GetStackFrameAtIndex(0);
543                 if (frame_sp)
544                   SetFrameSP(frame_sp);
545               }
546             }
547           }
548         }
549       }
550     }
551   }
552 }
553 
554 void ExecutionContextRef::SetProcessPtr(Process *process) {
555   if (process) {
556     SetProcessSP(process->shared_from_this());
557   } else {
558     m_process_wp.reset();
559     m_target_wp.reset();
560   }
561 }
562 
563 void ExecutionContextRef::SetThreadPtr(Thread *thread) {
564   if (thread) {
565     SetThreadSP(thread->shared_from_this());
566   } else {
567     ClearThread();
568     m_process_wp.reset();
569     m_target_wp.reset();
570   }
571 }
572 
573 void ExecutionContextRef::SetFramePtr(StackFrame *frame) {
574   if (frame)
575     SetFrameSP(frame->shared_from_this());
576   else
577     Clear();
578 }
579 
580 lldb::TargetSP ExecutionContextRef::GetTargetSP() const {
581   lldb::TargetSP target_sp(m_target_wp.lock());
582   if (target_sp && !target_sp->IsValid())
583     target_sp.reset();
584   return target_sp;
585 }
586 
587 lldb::ProcessSP ExecutionContextRef::GetProcessSP() const {
588   lldb::ProcessSP process_sp(m_process_wp.lock());
589   if (process_sp && !process_sp->IsValid())
590     process_sp.reset();
591   return process_sp;
592 }
593 
594 lldb::ThreadSP ExecutionContextRef::GetThreadSP() const {
595   lldb::ThreadSP thread_sp(m_thread_wp.lock());
596 
597   if (m_tid != LLDB_INVALID_THREAD_ID) {
598     // We check if the thread has been destroyed in cases where clients might
599     // still have shared pointer to a thread, but the thread is not valid
600     // anymore (not part of the process)
601     if (!thread_sp || !thread_sp->IsValid()) {
602       lldb::ProcessSP process_sp(GetProcessSP());
603       if (process_sp && process_sp->IsValid()) {
604         thread_sp = process_sp->GetThreadList().FindThreadByID(m_tid);
605         m_thread_wp = thread_sp;
606       }
607     }
608   }
609 
610   // Check that we aren't about to return an invalid thread sp.  We might
611   // return a nullptr thread_sp, but don't return an invalid one.
612 
613   if (thread_sp && !thread_sp->IsValid())
614     thread_sp.reset();
615 
616   return thread_sp;
617 }
618 
619 lldb::StackFrameSP ExecutionContextRef::GetFrameSP() const {
620   if (m_stack_id.IsValid()) {
621     lldb::ThreadSP thread_sp(GetThreadSP());
622     if (thread_sp)
623       return thread_sp->GetFrameWithStackID(m_stack_id);
624   }
625   return lldb::StackFrameSP();
626 }
627 
628 ExecutionContext
629 ExecutionContextRef::Lock(bool thread_and_frame_only_if_stopped) const {
630   return ExecutionContext(this, thread_and_frame_only_if_stopped);
631 }
632