1 //===-- ValueObjectDynamicValue.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 
11 #include "lldb/Core/ValueObjectDynamicValue.h"
12 
13 // C Includes
14 // C++ Includes
15 // Other libraries and framework includes
16 // Project includes
17 #include "lldb/Core/Log.h"
18 #include "lldb/Core/Module.h"
19 #include "lldb/Core/ValueObjectList.h"
20 #include "lldb/Core/Value.h"
21 #include "lldb/Core/ValueObject.h"
22 
23 #include "lldb/Symbol/CompilerType.h"
24 #include "lldb/Symbol/ObjectFile.h"
25 #include "lldb/Symbol/SymbolContext.h"
26 #include "lldb/Symbol/Type.h"
27 #include "lldb/Symbol/Variable.h"
28 
29 #include "lldb/Target/ExecutionContext.h"
30 #include "lldb/Target/LanguageRuntime.h"
31 #include "lldb/Target/Process.h"
32 #include "lldb/Target/RegisterContext.h"
33 #include "lldb/Target/Target.h"
34 #include "lldb/Target/Thread.h"
35 
36 using namespace lldb_private;
37 
38 ValueObjectDynamicValue::ValueObjectDynamicValue (ValueObject &parent, lldb::DynamicValueType use_dynamic) :
39     ValueObject(parent),
40     m_address (),
41     m_dynamic_type_info(),
42     m_use_dynamic (use_dynamic)
43 {
44     SetName (parent.GetName());
45 }
46 
47 ValueObjectDynamicValue::~ValueObjectDynamicValue()
48 {
49     m_owning_valobj_sp.reset();
50 }
51 
52 CompilerType
53 ValueObjectDynamicValue::GetCompilerTypeImpl ()
54 {
55     const bool success = UpdateValueIfNeeded(false);
56     if (success)
57     {
58         if (m_dynamic_type_info.HasType())
59             return m_value.GetCompilerType();
60         else
61             return m_parent->GetCompilerType();
62     }
63     return m_parent->GetCompilerType();
64 }
65 
66 ConstString
67 ValueObjectDynamicValue::GetTypeName()
68 {
69     const bool success = UpdateValueIfNeeded(false);
70     if (success)
71     {
72         if (m_dynamic_type_info.HasName())
73             return m_dynamic_type_info.GetName();
74     }
75     return m_parent->GetTypeName();
76 }
77 
78 TypeImpl
79 ValueObjectDynamicValue::GetTypeImpl ()
80 {
81     const bool success = UpdateValueIfNeeded(false);
82     if (success && m_type_impl.IsValid())
83     {
84         return m_type_impl;
85     }
86     return m_parent->GetTypeImpl();
87 }
88 
89 ConstString
90 ValueObjectDynamicValue::GetQualifiedTypeName()
91 {
92     const bool success = UpdateValueIfNeeded(false);
93     if (success)
94     {
95         if (m_dynamic_type_info.HasName())
96             return m_dynamic_type_info.GetName();
97     }
98     return m_parent->GetQualifiedTypeName();
99 }
100 
101 ConstString
102 ValueObjectDynamicValue::GetDisplayTypeName()
103 {
104     const bool success = UpdateValueIfNeeded(false);
105     if (success)
106     {
107         if (m_dynamic_type_info.HasType())
108             return GetCompilerType().GetDisplayTypeName();
109         if (m_dynamic_type_info.HasName())
110             return m_dynamic_type_info.GetName();
111     }
112     return m_parent->GetDisplayTypeName();
113 }
114 
115 size_t
116 ValueObjectDynamicValue::CalculateNumChildren()
117 {
118     const bool success = UpdateValueIfNeeded(false);
119     if (success && m_dynamic_type_info.HasType())
120         return GetCompilerType().GetNumChildren (true);
121     else
122         return m_parent->GetNumChildren();
123 }
124 
125 uint64_t
126 ValueObjectDynamicValue::GetByteSize()
127 {
128     const bool success = UpdateValueIfNeeded(false);
129     if (success && m_dynamic_type_info.HasType())
130         return m_value.GetValueByteSize(nullptr);
131     else
132         return m_parent->GetByteSize();
133 }
134 
135 lldb::ValueType
136 ValueObjectDynamicValue::GetValueType() const
137 {
138     return m_parent->GetValueType();
139 }
140 
141 
142 static TypeAndOrName
143 FixupTypeAndOrName (const TypeAndOrName& type_andor_name,
144                     ValueObject& parent)
145 {
146     TypeAndOrName ret(type_andor_name);
147     if (type_andor_name.HasType())
148     {
149         // The type will always be the type of the dynamic object.  If our parent's type was a pointer,
150         // then our type should be a pointer to the type of the dynamic object.  If a reference, then the original type
151         // should be okay...
152         CompilerType orig_type = type_andor_name.GetCompilerType();
153         CompilerType corrected_type = orig_type;
154         if (parent.IsPointerType())
155             corrected_type = orig_type.GetPointerType ();
156         else if (parent.IsPointerOrReferenceType())
157             corrected_type = orig_type.GetLValueReferenceType();
158         ret.SetCompilerType(corrected_type);
159     }
160     else /*if (m_dynamic_type_info.HasName())*/
161     {
162         // If we are here we need to adjust our dynamic type name to include the correct & or * symbol
163         std::string corrected_name (type_andor_name.GetName().GetCString());
164         if (parent.IsPointerType())
165             corrected_name.append(" *");
166         else if (parent.IsPointerOrReferenceType())
167             corrected_name.append(" &");
168         // the parent type should be a correctly pointer'ed or referenc'ed type
169         ret.SetCompilerType(parent.GetCompilerType());
170         ret.SetName(corrected_name.c_str());
171     }
172     return ret;
173 }
174 
175 bool
176 ValueObjectDynamicValue::UpdateValue ()
177 {
178     SetValueIsValid (false);
179     m_error.Clear();
180 
181     if (!m_parent->UpdateValueIfNeeded(false))
182     {
183         // The dynamic value failed to get an error, pass the error along
184         if (m_error.Success() && m_parent->GetError().Fail())
185             m_error = m_parent->GetError();
186         return false;
187     }
188 
189     // Setting our type_sp to NULL will route everything back through our
190     // parent which is equivalent to not using dynamic values.
191     if (m_use_dynamic == lldb::eNoDynamicValues)
192     {
193         m_dynamic_type_info.Clear();
194         return true;
195     }
196 
197     ExecutionContext exe_ctx (GetExecutionContextRef());
198     Target *target = exe_ctx.GetTargetPtr();
199     if (target)
200     {
201         m_data.SetByteOrder(target->GetArchitecture().GetByteOrder());
202         m_data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
203     }
204 
205     // First make sure our Type and/or Address haven't changed:
206     Process *process = exe_ctx.GetProcessPtr();
207     if (!process)
208         return false;
209 
210     TypeAndOrName class_type_or_name;
211     Address dynamic_address;
212     bool found_dynamic_type = false;
213     Value::ValueType value_type;
214 
215     lldb::LanguageType known_type = m_parent->GetObjectRuntimeLanguage();
216     if (known_type != lldb::eLanguageTypeUnknown && known_type != lldb::eLanguageTypeC)
217     {
218         LanguageRuntime *runtime = process->GetLanguageRuntime (known_type);
219         if (runtime)
220             found_dynamic_type = runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address, value_type);
221     }
222     else
223     {
224         LanguageRuntime *cpp_runtime = process->GetLanguageRuntime (lldb::eLanguageTypeC_plus_plus);
225         if (cpp_runtime)
226             found_dynamic_type = cpp_runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address, value_type);
227 
228         if (!found_dynamic_type)
229         {
230             LanguageRuntime *objc_runtime = process->GetLanguageRuntime (lldb::eLanguageTypeObjC);
231             if (objc_runtime)
232                 found_dynamic_type = objc_runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address, value_type);
233         }
234     }
235 
236     // Getting the dynamic value may have run the program a bit, and so marked us as needing updating, but we really
237     // don't...
238 
239     m_update_point.SetUpdated();
240 
241     if (found_dynamic_type)
242     {
243         if (class_type_or_name.HasType())
244         {
245             m_type_impl = TypeImpl(m_parent->GetCompilerType(),FixupTypeAndOrName(class_type_or_name, *m_parent).GetCompilerType());
246         }
247         else
248         {
249             m_type_impl.Clear();
250         }
251     }
252     else
253     {
254         m_type_impl.Clear();
255     }
256 
257     // If we don't have a dynamic type, then make ourselves just a echo of our parent.
258     // Or we could return false, and make ourselves an echo of our parent?
259     if (!found_dynamic_type)
260     {
261         if (m_dynamic_type_info)
262             SetValueDidChange(true);
263         ClearDynamicTypeInformation();
264         m_dynamic_type_info.Clear();
265         m_value = m_parent->GetValue();
266         m_error = m_value.GetValueAsData (&exe_ctx, m_data, 0, GetModule().get());
267         return m_error.Success();
268     }
269 
270     Value old_value(m_value);
271 
272     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_TYPES));
273 
274     bool has_changed_type = false;
275 
276     if (!m_dynamic_type_info)
277     {
278         m_dynamic_type_info = class_type_or_name;
279         has_changed_type = true;
280     }
281     else if (class_type_or_name != m_dynamic_type_info)
282     {
283         // We are another type, we need to tear down our children...
284         m_dynamic_type_info = class_type_or_name;
285         SetValueDidChange (true);
286         has_changed_type = true;
287     }
288 
289     if (has_changed_type)
290         ClearDynamicTypeInformation ();
291 
292     if (!m_address.IsValid() || m_address != dynamic_address)
293     {
294         if (m_address.IsValid())
295             SetValueDidChange (true);
296 
297         // We've moved, so we should be fine...
298         m_address = dynamic_address;
299         lldb::TargetSP target_sp (GetTargetSP());
300         lldb::addr_t load_address = m_address.GetLoadAddress(target_sp.get());
301         m_value.GetScalar() = load_address;
302     }
303 
304     m_dynamic_type_info = FixupTypeAndOrName(m_dynamic_type_info, *m_parent);
305 
306     //m_value.SetContext (Value::eContextTypeClangType, corrected_type);
307     m_value.SetCompilerType (m_dynamic_type_info.GetCompilerType());
308 
309     m_value.SetValueType(value_type);
310 
311     if (has_changed_type && log)
312         log->Printf("[%s %p] has a new dynamic type %s", GetName().GetCString(),
313                     static_cast<void*>(this), GetTypeName().GetCString());
314 
315     if (m_address.IsValid() && m_dynamic_type_info)
316     {
317         // The variable value is in the Scalar value inside the m_value.
318         // We can point our m_data right to it.
319         m_error = m_value.GetValueAsData (&exe_ctx, m_data, 0, GetModule().get());
320         if (m_error.Success())
321         {
322             if (!CanProvideValue())
323             {
324                 // this value object represents an aggregate type whose
325                 // children have values, but this object does not. So we
326                 // say we are changed if our location has changed.
327                 SetValueDidChange (m_value.GetValueType() != old_value.GetValueType() || m_value.GetScalar() != old_value.GetScalar());
328             }
329 
330             SetValueIsValid (true);
331             return true;
332         }
333     }
334 
335     // We get here if we've failed above...
336     SetValueIsValid (false);
337     return false;
338 }
339 
340 
341 
342 bool
343 ValueObjectDynamicValue::IsInScope ()
344 {
345     return m_parent->IsInScope();
346 }
347 
348 bool
349 ValueObjectDynamicValue::SetValueFromCString (const char *value_str, Error& error)
350 {
351     if (!UpdateValueIfNeeded(false))
352     {
353         error.SetErrorString("unable to read value");
354         return false;
355     }
356 
357     uint64_t my_value = GetValueAsUnsigned(UINT64_MAX);
358     uint64_t parent_value = m_parent->GetValueAsUnsigned(UINT64_MAX);
359 
360     if (my_value == UINT64_MAX || parent_value == UINT64_MAX)
361     {
362         error.SetErrorString("unable to read value");
363         return false;
364     }
365 
366     // if we are at an offset from our parent, in order to set ourselves correctly we would need
367     // to change the new value so that it refers to the correct dynamic type. we choose not to deal
368     // with that - if anything more than a value overwrite is required, you should be using the
369     // expression parser instead of the value editing facility
370     if (my_value != parent_value)
371     {
372         // but NULL'ing out a value should always be allowed
373         if (strcmp(value_str,"0"))
374         {
375             error.SetErrorString("unable to modify dynamic value, use 'expression' command");
376             return false;
377         }
378     }
379 
380     bool ret_val = m_parent->SetValueFromCString(value_str,error);
381     SetNeedsUpdate();
382     return ret_val;
383 }
384 
385 bool
386 ValueObjectDynamicValue::SetData (DataExtractor &data, Error &error)
387 {
388     if (!UpdateValueIfNeeded(false))
389     {
390         error.SetErrorString("unable to read value");
391         return false;
392     }
393 
394     uint64_t my_value = GetValueAsUnsigned(UINT64_MAX);
395     uint64_t parent_value = m_parent->GetValueAsUnsigned(UINT64_MAX);
396 
397     if (my_value == UINT64_MAX || parent_value == UINT64_MAX)
398     {
399         error.SetErrorString("unable to read value");
400         return false;
401     }
402 
403     // if we are at an offset from our parent, in order to set ourselves correctly we would need
404     // to change the new value so that it refers to the correct dynamic type. we choose not to deal
405     // with that - if anything more than a value overwrite is required, you should be using the
406     // expression parser instead of the value editing facility
407     if (my_value != parent_value)
408     {
409         // but NULL'ing out a value should always be allowed
410         lldb::offset_t offset = 0;
411 
412         if (data.GetPointer(&offset) != 0)
413         {
414             error.SetErrorString("unable to modify dynamic value, use 'expression' command");
415             return false;
416         }
417     }
418 
419     bool ret_val = m_parent->SetData(data, error);
420     SetNeedsUpdate();
421     return ret_val;
422 }
423 
424 bool
425 ValueObjectDynamicValue::GetDeclaration (Declaration &decl)
426 {
427     if (m_parent)
428         return m_parent->GetDeclaration(decl);
429 
430     return ValueObject::GetDeclaration(decl);
431 }
432