xref: /freebsd/contrib/llvm-project/lldb/source/Symbol/ObjectFile.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1 //===-- ObjectFile.cpp ----------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/Symbol/ObjectFile.h"
10 #include "lldb/Core/Module.h"
11 #include "lldb/Core/ModuleSpec.h"
12 #include "lldb/Core/PluginManager.h"
13 #include "lldb/Core/Section.h"
14 #include "lldb/Symbol/CallFrameInfo.h"
15 #include "lldb/Symbol/ObjectContainer.h"
16 #include "lldb/Symbol/SymbolFile.h"
17 #include "lldb/Target/Process.h"
18 #include "lldb/Target/SectionLoadList.h"
19 #include "lldb/Target/Target.h"
20 #include "lldb/Utility/DataBuffer.h"
21 #include "lldb/Utility/DataBufferHeap.h"
22 #include "lldb/Utility/LLDBLog.h"
23 #include "lldb/Utility/Log.h"
24 #include "lldb/Utility/Timer.h"
25 #include "lldb/lldb-private.h"
26 
27 #include "llvm/Support/DJB.h"
28 
29 using namespace lldb;
30 using namespace lldb_private;
31 
32 char ObjectFile::ID;
33 size_t ObjectFile::g_initial_bytes_to_read = 512;
34 
35 static ObjectFileSP
CreateObjectFromContainer(const lldb::ModuleSP & module_sp,const FileSpec * file,lldb::offset_t file_offset,lldb::offset_t file_size,DataBufferSP data_sp,lldb::offset_t & data_offset)36 CreateObjectFromContainer(const lldb::ModuleSP &module_sp, const FileSpec *file,
37                           lldb::offset_t file_offset, lldb::offset_t file_size,
38                           DataBufferSP data_sp, lldb::offset_t &data_offset) {
39   ObjectContainerCreateInstance callback;
40   for (uint32_t idx = 0;
41        (callback = PluginManager::GetObjectContainerCreateCallbackAtIndex(
42             idx)) != nullptr;
43        ++idx) {
44     std::unique_ptr<ObjectContainer> object_container_up(callback(
45         module_sp, data_sp, data_offset, file, file_offset, file_size));
46     if (object_container_up)
47       return object_container_up->GetObjectFile(file);
48   }
49   return {};
50 }
51 
52 ObjectFileSP
FindPlugin(const lldb::ModuleSP & module_sp,const FileSpec * file,lldb::offset_t file_offset,lldb::offset_t file_size,DataBufferSP & data_sp,lldb::offset_t & data_offset)53 ObjectFile::FindPlugin(const lldb::ModuleSP &module_sp, const FileSpec *file,
54                        lldb::offset_t file_offset, lldb::offset_t file_size,
55                        DataBufferSP &data_sp, lldb::offset_t &data_offset) {
56   LLDB_SCOPED_TIMERF(
57       "ObjectFile::FindPlugin (module = %s, file = %p, file_offset = "
58       "0x%8.8" PRIx64 ", file_size = 0x%8.8" PRIx64 ")",
59       module_sp->GetFileSpec().GetPath().c_str(),
60       static_cast<const void *>(file), static_cast<uint64_t>(file_offset),
61       static_cast<uint64_t>(file_size));
62 
63   if (!module_sp)
64     return {};
65 
66   if (!file)
67     return {};
68 
69   if (!data_sp) {
70     const bool file_exists = FileSystem::Instance().Exists(*file);
71     // We have an object name which most likely means we have a .o file in
72     // a static archive (.a file). Try and see if we have a cached archive
73     // first without reading any data first
74     if (file_exists && module_sp->GetObjectName()) {
75       ObjectFileSP object_file_sp = CreateObjectFromContainer(
76           module_sp, file, file_offset, file_size, data_sp, data_offset);
77       if (object_file_sp)
78         return object_file_sp;
79     }
80     // Ok, we didn't find any containers that have a named object, now lets
81     // read the first 512 bytes from the file so the object file and object
82     // container plug-ins can use these bytes to see if they can parse this
83     // file.
84     if (file_size > 0) {
85       data_sp = FileSystem::Instance().CreateDataBuffer(
86           file->GetPath(), g_initial_bytes_to_read, file_offset);
87       data_offset = 0;
88     }
89   }
90 
91   if (!data_sp || data_sp->GetByteSize() == 0) {
92     // Check for archive file with format "/path/to/archive.a(object.o)"
93     llvm::SmallString<256> path_with_object;
94     module_sp->GetFileSpec().GetPath(path_with_object);
95 
96     FileSpec archive_file;
97     ConstString archive_object;
98     const bool must_exist = true;
99     if (ObjectFile::SplitArchivePathWithObject(path_with_object, archive_file,
100                                                archive_object, must_exist)) {
101       file_size = FileSystem::Instance().GetByteSize(archive_file);
102       if (file_size > 0) {
103         file = &archive_file;
104         module_sp->SetFileSpecAndObjectName(archive_file, archive_object);
105         // Check if this is a object container by iterating through all
106         // object container plugin instances and then trying to get an
107         // object file from the container plugins since we had a name.
108         // Also, don't read
109         // ANY data in case there is data cached in the container plug-ins
110         // (like BSD archives caching the contained objects within an
111         // file).
112         ObjectFileSP object_file_sp = CreateObjectFromContainer(
113             module_sp, file, file_offset, file_size, data_sp, data_offset);
114         if (object_file_sp)
115           return object_file_sp;
116         // We failed to find any cached object files in the container plug-
117         // ins, so lets read the first 512 bytes and try again below...
118         data_sp = FileSystem::Instance().CreateDataBuffer(
119             archive_file.GetPath(), g_initial_bytes_to_read, file_offset);
120       }
121     }
122   }
123 
124   if (data_sp && data_sp->GetByteSize() > 0) {
125     // Check if this is a normal object file by iterating through all
126     // object file plugin instances.
127     ObjectFileCreateInstance callback;
128     for (uint32_t idx = 0;
129          (callback = PluginManager::GetObjectFileCreateCallbackAtIndex(idx)) !=
130          nullptr;
131          ++idx) {
132       ObjectFileSP object_file_sp(callback(module_sp, data_sp, data_offset,
133                                            file, file_offset, file_size));
134       if (object_file_sp.get())
135         return object_file_sp;
136     }
137 
138     // Check if this is a object container by iterating through all object
139     // container plugin instances and then trying to get an object file
140     // from the container.
141     ObjectFileSP object_file_sp = CreateObjectFromContainer(
142         module_sp, file, file_offset, file_size, data_sp, data_offset);
143     if (object_file_sp)
144       return object_file_sp;
145   }
146 
147   // We didn't find it, so clear our shared pointer in case it contains
148   // anything and return an empty shared pointer
149   return {};
150 }
151 
FindPlugin(const lldb::ModuleSP & module_sp,const ProcessSP & process_sp,lldb::addr_t header_addr,WritableDataBufferSP data_sp)152 ObjectFileSP ObjectFile::FindPlugin(const lldb::ModuleSP &module_sp,
153                                     const ProcessSP &process_sp,
154                                     lldb::addr_t header_addr,
155                                     WritableDataBufferSP data_sp) {
156   ObjectFileSP object_file_sp;
157 
158   if (module_sp) {
159     LLDB_SCOPED_TIMERF("ObjectFile::FindPlugin (module = "
160                        "%s, process = %p, header_addr = "
161                        "0x%" PRIx64 ")",
162                        module_sp->GetFileSpec().GetPath().c_str(),
163                        static_cast<void *>(process_sp.get()), header_addr);
164     uint32_t idx;
165 
166     // Check if this is a normal object file by iterating through all object
167     // file plugin instances.
168     ObjectFileCreateMemoryInstance create_callback;
169     for (idx = 0;
170          (create_callback =
171               PluginManager::GetObjectFileCreateMemoryCallbackAtIndex(idx)) !=
172          nullptr;
173          ++idx) {
174       object_file_sp.reset(
175           create_callback(module_sp, data_sp, process_sp, header_addr));
176       if (object_file_sp.get())
177         return object_file_sp;
178     }
179   }
180 
181   // We didn't find it, so clear our shared pointer in case it contains
182   // anything and return an empty shared pointer
183   object_file_sp.reset();
184   return object_file_sp;
185 }
186 
IsObjectFile(lldb_private::FileSpec file_spec)187 bool ObjectFile::IsObjectFile(lldb_private::FileSpec file_spec) {
188   DataBufferSP data_sp;
189   offset_t data_offset = 0;
190   ModuleSP module_sp = std::make_shared<Module>(file_spec);
191   return static_cast<bool>(ObjectFile::FindPlugin(
192       module_sp, &file_spec, 0, FileSystem::Instance().GetByteSize(file_spec),
193       data_sp, data_offset));
194 }
195 
GetModuleSpecifications(const FileSpec & file,lldb::offset_t file_offset,lldb::offset_t file_size,ModuleSpecList & specs,DataBufferSP data_sp)196 size_t ObjectFile::GetModuleSpecifications(const FileSpec &file,
197                                            lldb::offset_t file_offset,
198                                            lldb::offset_t file_size,
199                                            ModuleSpecList &specs,
200                                            DataBufferSP data_sp) {
201   if (!data_sp)
202     data_sp = FileSystem::Instance().CreateDataBuffer(
203         file.GetPath(), g_initial_bytes_to_read, file_offset);
204   if (data_sp) {
205     if (file_size == 0) {
206       const lldb::offset_t actual_file_size =
207           FileSystem::Instance().GetByteSize(file);
208       if (actual_file_size > file_offset)
209         file_size = actual_file_size - file_offset;
210     }
211     return ObjectFile::GetModuleSpecifications(file,        // file spec
212                                                data_sp,     // data bytes
213                                                0,           // data offset
214                                                file_offset, // file offset
215                                                file_size,   // file length
216                                                specs);
217   }
218   return 0;
219 }
220 
GetModuleSpecifications(const lldb_private::FileSpec & file,lldb::DataBufferSP & data_sp,lldb::offset_t data_offset,lldb::offset_t file_offset,lldb::offset_t file_size,lldb_private::ModuleSpecList & specs)221 size_t ObjectFile::GetModuleSpecifications(
222     const lldb_private::FileSpec &file, lldb::DataBufferSP &data_sp,
223     lldb::offset_t data_offset, lldb::offset_t file_offset,
224     lldb::offset_t file_size, lldb_private::ModuleSpecList &specs) {
225   const size_t initial_count = specs.GetSize();
226   ObjectFileGetModuleSpecifications callback;
227   uint32_t i;
228   // Try the ObjectFile plug-ins
229   for (i = 0;
230        (callback =
231             PluginManager::GetObjectFileGetModuleSpecificationsCallbackAtIndex(
232                 i)) != nullptr;
233        ++i) {
234     if (callback(file, data_sp, data_offset, file_offset, file_size, specs) > 0)
235       return specs.GetSize() - initial_count;
236   }
237 
238   // Try the ObjectContainer plug-ins
239   for (i = 0;
240        (callback = PluginManager::
241             GetObjectContainerGetModuleSpecificationsCallbackAtIndex(i)) !=
242        nullptr;
243        ++i) {
244     if (callback(file, data_sp, data_offset, file_offset, file_size, specs) > 0)
245       return specs.GetSize() - initial_count;
246   }
247   return 0;
248 }
249 
ObjectFile(const lldb::ModuleSP & module_sp,const FileSpec * file_spec_ptr,lldb::offset_t file_offset,lldb::offset_t length,lldb::DataBufferSP data_sp,lldb::offset_t data_offset)250 ObjectFile::ObjectFile(const lldb::ModuleSP &module_sp,
251                        const FileSpec *file_spec_ptr,
252                        lldb::offset_t file_offset, lldb::offset_t length,
253                        lldb::DataBufferSP data_sp, lldb::offset_t data_offset)
254     : ModuleChild(module_sp),
255       m_file(), // This file could be different from the original module's file
256       m_type(eTypeInvalid), m_strata(eStrataInvalid),
257       m_file_offset(file_offset), m_length(length), m_data(), m_process_wp(),
258       m_memory_addr(LLDB_INVALID_ADDRESS), m_sections_up(), m_symtab_up(),
259       m_symtab_once_up(new llvm::once_flag()) {
260   if (file_spec_ptr)
261     m_file = *file_spec_ptr;
262   if (data_sp)
263     m_data.SetData(data_sp, data_offset, length);
264   Log *log = GetLog(LLDBLog::Object);
265   LLDB_LOGF(log,
266             "%p ObjectFile::ObjectFile() module = %p (%s), file = %s, "
267             "file_offset = 0x%8.8" PRIx64 ", size = %" PRIu64,
268             static_cast<void *>(this), static_cast<void *>(module_sp.get()),
269             module_sp->GetSpecificationDescription().c_str(),
270             m_file ? m_file.GetPath().c_str() : "<NULL>", m_file_offset,
271             m_length);
272 }
273 
ObjectFile(const lldb::ModuleSP & module_sp,const ProcessSP & process_sp,lldb::addr_t header_addr,DataBufferSP header_data_sp)274 ObjectFile::ObjectFile(const lldb::ModuleSP &module_sp,
275                        const ProcessSP &process_sp, lldb::addr_t header_addr,
276                        DataBufferSP header_data_sp)
277     : ModuleChild(module_sp), m_file(), m_type(eTypeInvalid),
278       m_strata(eStrataInvalid), m_file_offset(0), m_length(0), m_data(),
279       m_process_wp(process_sp), m_memory_addr(header_addr), m_sections_up(),
280       m_symtab_up(), m_symtab_once_up(new llvm::once_flag()) {
281   if (header_data_sp)
282     m_data.SetData(header_data_sp, 0, header_data_sp->GetByteSize());
283   Log *log = GetLog(LLDBLog::Object);
284   LLDB_LOGF(log,
285             "%p ObjectFile::ObjectFile() module = %p (%s), process = %p, "
286             "header_addr = 0x%" PRIx64,
287             static_cast<void *>(this), static_cast<void *>(module_sp.get()),
288             module_sp->GetSpecificationDescription().c_str(),
289             static_cast<void *>(process_sp.get()), m_memory_addr);
290 }
291 
~ObjectFile()292 ObjectFile::~ObjectFile() {
293   Log *log = GetLog(LLDBLog::Object);
294   LLDB_LOGF(log, "%p ObjectFile::~ObjectFile ()\n", static_cast<void *>(this));
295 }
296 
SetModulesArchitecture(const ArchSpec & new_arch)297 bool ObjectFile::SetModulesArchitecture(const ArchSpec &new_arch) {
298   ModuleSP module_sp(GetModule());
299   if (module_sp)
300     return module_sp->SetArchitecture(new_arch);
301   return false;
302 }
303 
GetAddressClass(addr_t file_addr)304 AddressClass ObjectFile::GetAddressClass(addr_t file_addr) {
305   Symtab *symtab = GetSymtab();
306   if (symtab) {
307     Symbol *symbol = symtab->FindSymbolContainingFileAddress(file_addr);
308     if (symbol) {
309       if (symbol->ValueIsAddress()) {
310         const SectionSP section_sp(symbol->GetAddressRef().GetSection());
311         if (section_sp) {
312           const SectionType section_type = section_sp->GetType();
313           switch (section_type) {
314           case eSectionTypeInvalid:
315             return AddressClass::eUnknown;
316           case eSectionTypeCode:
317             return AddressClass::eCode;
318           case eSectionTypeContainer:
319             return AddressClass::eUnknown;
320           case eSectionTypeData:
321           case eSectionTypeDataCString:
322           case eSectionTypeDataCStringPointers:
323           case eSectionTypeDataSymbolAddress:
324           case eSectionTypeData4:
325           case eSectionTypeData8:
326           case eSectionTypeData16:
327           case eSectionTypeDataPointers:
328           case eSectionTypeZeroFill:
329           case eSectionTypeDataObjCMessageRefs:
330           case eSectionTypeDataObjCCFStrings:
331           case eSectionTypeGoSymtab:
332             return AddressClass::eData;
333           case eSectionTypeDebug:
334           case eSectionTypeDWARFDebugAbbrev:
335           case eSectionTypeDWARFDebugAbbrevDwo:
336           case eSectionTypeDWARFDebugAddr:
337           case eSectionTypeDWARFDebugAranges:
338           case eSectionTypeDWARFDebugCuIndex:
339           case eSectionTypeDWARFDebugFrame:
340           case eSectionTypeDWARFDebugInfo:
341           case eSectionTypeDWARFDebugInfoDwo:
342           case eSectionTypeDWARFDebugLine:
343           case eSectionTypeDWARFDebugLineStr:
344           case eSectionTypeDWARFDebugLoc:
345           case eSectionTypeDWARFDebugLocDwo:
346           case eSectionTypeDWARFDebugLocLists:
347           case eSectionTypeDWARFDebugLocListsDwo:
348           case eSectionTypeDWARFDebugMacInfo:
349           case eSectionTypeDWARFDebugMacro:
350           case eSectionTypeDWARFDebugNames:
351           case eSectionTypeDWARFDebugPubNames:
352           case eSectionTypeDWARFDebugPubTypes:
353           case eSectionTypeDWARFDebugRanges:
354           case eSectionTypeDWARFDebugRngLists:
355           case eSectionTypeDWARFDebugRngListsDwo:
356           case eSectionTypeDWARFDebugStr:
357           case eSectionTypeDWARFDebugStrDwo:
358           case eSectionTypeDWARFDebugStrOffsets:
359           case eSectionTypeDWARFDebugStrOffsetsDwo:
360           case eSectionTypeDWARFDebugTuIndex:
361           case eSectionTypeDWARFDebugTypes:
362           case eSectionTypeDWARFDebugTypesDwo:
363           case eSectionTypeDWARFAppleNames:
364           case eSectionTypeDWARFAppleTypes:
365           case eSectionTypeDWARFAppleNamespaces:
366           case eSectionTypeDWARFAppleObjC:
367           case eSectionTypeDWARFGNUDebugAltLink:
368           case eSectionTypeCTF:
369           case eSectionTypeSwiftModules:
370             return AddressClass::eDebug;
371           case eSectionTypeEHFrame:
372           case eSectionTypeARMexidx:
373           case eSectionTypeARMextab:
374           case eSectionTypeCompactUnwind:
375             return AddressClass::eRuntime;
376           case eSectionTypeELFSymbolTable:
377           case eSectionTypeELFDynamicSymbols:
378           case eSectionTypeELFRelocationEntries:
379           case eSectionTypeELFDynamicLinkInfo:
380           case eSectionTypeOther:
381             return AddressClass::eUnknown;
382           case eSectionTypeAbsoluteAddress:
383             // In case of absolute sections decide the address class based on
384             // the symbol type because the section type isn't specify if it is
385             // a code or a data section.
386             break;
387           }
388         }
389       }
390 
391       const SymbolType symbol_type = symbol->GetType();
392       switch (symbol_type) {
393       case eSymbolTypeAny:
394         return AddressClass::eUnknown;
395       case eSymbolTypeAbsolute:
396         return AddressClass::eUnknown;
397       case eSymbolTypeCode:
398         return AddressClass::eCode;
399       case eSymbolTypeTrampoline:
400         return AddressClass::eCode;
401       case eSymbolTypeResolver:
402         return AddressClass::eCode;
403       case eSymbolTypeData:
404         return AddressClass::eData;
405       case eSymbolTypeRuntime:
406         return AddressClass::eRuntime;
407       case eSymbolTypeException:
408         return AddressClass::eRuntime;
409       case eSymbolTypeSourceFile:
410         return AddressClass::eDebug;
411       case eSymbolTypeHeaderFile:
412         return AddressClass::eDebug;
413       case eSymbolTypeObjectFile:
414         return AddressClass::eDebug;
415       case eSymbolTypeCommonBlock:
416         return AddressClass::eDebug;
417       case eSymbolTypeBlock:
418         return AddressClass::eDebug;
419       case eSymbolTypeLocal:
420         return AddressClass::eData;
421       case eSymbolTypeParam:
422         return AddressClass::eData;
423       case eSymbolTypeVariable:
424         return AddressClass::eData;
425       case eSymbolTypeVariableType:
426         return AddressClass::eDebug;
427       case eSymbolTypeLineEntry:
428         return AddressClass::eDebug;
429       case eSymbolTypeLineHeader:
430         return AddressClass::eDebug;
431       case eSymbolTypeScopeBegin:
432         return AddressClass::eDebug;
433       case eSymbolTypeScopeEnd:
434         return AddressClass::eDebug;
435       case eSymbolTypeAdditional:
436         return AddressClass::eUnknown;
437       case eSymbolTypeCompiler:
438         return AddressClass::eDebug;
439       case eSymbolTypeInstrumentation:
440         return AddressClass::eDebug;
441       case eSymbolTypeUndefined:
442         return AddressClass::eUnknown;
443       case eSymbolTypeObjCClass:
444         return AddressClass::eRuntime;
445       case eSymbolTypeObjCMetaClass:
446         return AddressClass::eRuntime;
447       case eSymbolTypeObjCIVar:
448         return AddressClass::eRuntime;
449       case eSymbolTypeReExported:
450         return AddressClass::eRuntime;
451       }
452     }
453   }
454   return AddressClass::eUnknown;
455 }
456 
ReadMemory(const ProcessSP & process_sp,lldb::addr_t addr,size_t byte_size)457 DataBufferSP ObjectFile::ReadMemory(const ProcessSP &process_sp,
458                                     lldb::addr_t addr, size_t byte_size) {
459   DataBufferSP data_sp;
460   if (process_sp) {
461     std::unique_ptr<DataBufferHeap> data_up(new DataBufferHeap(byte_size, 0));
462     Status error;
463     const size_t bytes_read = process_sp->ReadMemory(
464         addr, data_up->GetBytes(), data_up->GetByteSize(), error);
465     if (bytes_read == byte_size)
466       data_sp.reset(data_up.release());
467   }
468   return data_sp;
469 }
470 
GetData(lldb::offset_t offset,size_t length,DataExtractor & data) const471 size_t ObjectFile::GetData(lldb::offset_t offset, size_t length,
472                            DataExtractor &data) const {
473   // The entire file has already been mmap'ed into m_data, so just copy from
474   // there as the back mmap buffer will be shared with shared pointers.
475   return data.SetData(m_data, offset, length);
476 }
477 
CopyData(lldb::offset_t offset,size_t length,void * dst) const478 size_t ObjectFile::CopyData(lldb::offset_t offset, size_t length,
479                             void *dst) const {
480   // The entire file has already been mmap'ed into m_data, so just copy from
481   // there Note that the data remains in target byte order.
482   return m_data.CopyData(offset, length, dst);
483 }
484 
ReadSectionData(Section * section,lldb::offset_t section_offset,void * dst,size_t dst_len)485 size_t ObjectFile::ReadSectionData(Section *section,
486                                    lldb::offset_t section_offset, void *dst,
487                                    size_t dst_len) {
488   assert(section);
489   section_offset *= section->GetTargetByteSize();
490 
491   // If some other objectfile owns this data, pass this to them.
492   if (section->GetObjectFile() != this)
493     return section->GetObjectFile()->ReadSectionData(section, section_offset,
494                                                      dst, dst_len);
495 
496   if (!section->IsRelocated())
497     RelocateSection(section);
498 
499   if (IsInMemory()) {
500     ProcessSP process_sp(m_process_wp.lock());
501     if (process_sp) {
502       Status error;
503       const addr_t base_load_addr =
504           section->GetLoadBaseAddress(&process_sp->GetTarget());
505       if (base_load_addr != LLDB_INVALID_ADDRESS)
506         return process_sp->ReadMemory(base_load_addr + section_offset, dst,
507                                       dst_len, error);
508     }
509   } else {
510     const lldb::offset_t section_file_size = section->GetFileSize();
511     if (section_offset < section_file_size) {
512       const size_t section_bytes_left = section_file_size - section_offset;
513       size_t section_dst_len = dst_len;
514       if (section_dst_len > section_bytes_left)
515         section_dst_len = section_bytes_left;
516       return CopyData(section->GetFileOffset() + section_offset,
517                       section_dst_len, dst);
518     } else {
519       if (section->GetType() == eSectionTypeZeroFill) {
520         const uint64_t section_size = section->GetByteSize();
521         const uint64_t section_bytes_left = section_size - section_offset;
522         uint64_t section_dst_len = dst_len;
523         if (section_dst_len > section_bytes_left)
524           section_dst_len = section_bytes_left;
525         memset(dst, 0, section_dst_len);
526         return section_dst_len;
527       }
528     }
529   }
530   return 0;
531 }
532 
533 // Get the section data the file on disk
ReadSectionData(Section * section,DataExtractor & section_data)534 size_t ObjectFile::ReadSectionData(Section *section,
535                                    DataExtractor &section_data) {
536   // If some other objectfile owns this data, pass this to them.
537   if (section->GetObjectFile() != this)
538     return section->GetObjectFile()->ReadSectionData(section, section_data);
539 
540   if (!section->IsRelocated())
541     RelocateSection(section);
542 
543   if (IsInMemory()) {
544     ProcessSP process_sp(m_process_wp.lock());
545     if (process_sp) {
546       const addr_t base_load_addr =
547           section->GetLoadBaseAddress(&process_sp->GetTarget());
548       if (base_load_addr != LLDB_INVALID_ADDRESS) {
549         DataBufferSP data_sp(
550             ReadMemory(process_sp, base_load_addr, section->GetByteSize()));
551         if (data_sp) {
552           section_data.SetData(data_sp, 0, data_sp->GetByteSize());
553           section_data.SetByteOrder(process_sp->GetByteOrder());
554           section_data.SetAddressByteSize(process_sp->GetAddressByteSize());
555           return section_data.GetByteSize();
556         }
557       }
558     }
559   }
560 
561   // The object file now contains a full mmap'ed copy of the object file
562   // data, so just use this
563   return GetData(section->GetFileOffset(), GetSectionDataSize(section),
564                  section_data);
565 }
566 
SplitArchivePathWithObject(llvm::StringRef path_with_object,FileSpec & archive_file,ConstString & archive_object,bool must_exist)567 bool ObjectFile::SplitArchivePathWithObject(llvm::StringRef path_with_object,
568                                             FileSpec &archive_file,
569                                             ConstString &archive_object,
570                                             bool must_exist) {
571   size_t len = path_with_object.size();
572   if (len < 2 || path_with_object.back() != ')')
573     return false;
574   llvm::StringRef archive = path_with_object.substr(0, path_with_object.rfind('('));
575   if (archive.empty())
576     return false;
577   llvm::StringRef object = path_with_object.substr(archive.size() + 1).drop_back();
578   archive_file.SetFile(archive, FileSpec::Style::native);
579   if (must_exist && !FileSystem::Instance().Exists(archive_file))
580     return false;
581   archive_object.SetString(object);
582   return true;
583 }
584 
ClearSymtab()585 void ObjectFile::ClearSymtab() {
586   ModuleSP module_sp(GetModule());
587   if (module_sp) {
588     Log *log = GetLog(LLDBLog::Object);
589     LLDB_LOGF(log, "%p ObjectFile::ClearSymtab () symtab = %p",
590               static_cast<void *>(this),
591               static_cast<void *>(m_symtab_up.get()));
592     // Since we need to clear the symbol table, we need a new llvm::once_flag
593     // instance so we can safely create another symbol table
594     m_symtab_once_up.reset(new llvm::once_flag());
595     m_symtab_up.reset();
596   }
597 }
598 
GetSectionList(bool update_module_section_list)599 SectionList *ObjectFile::GetSectionList(bool update_module_section_list) {
600   if (m_sections_up == nullptr) {
601     if (update_module_section_list) {
602       ModuleSP module_sp(GetModule());
603       if (module_sp) {
604         std::lock_guard<std::recursive_mutex> guard(module_sp->GetMutex());
605         CreateSections(*module_sp->GetUnifiedSectionList());
606       }
607     } else {
608       SectionList unified_section_list;
609       CreateSections(unified_section_list);
610     }
611   }
612   return m_sections_up.get();
613 }
614 
615 lldb::SymbolType
GetSymbolTypeFromName(llvm::StringRef name,lldb::SymbolType symbol_type_hint)616 ObjectFile::GetSymbolTypeFromName(llvm::StringRef name,
617                                   lldb::SymbolType symbol_type_hint) {
618   if (!name.empty()) {
619     if (name.starts_with("_OBJC_")) {
620       // ObjC
621       if (name.starts_with("_OBJC_CLASS_$_"))
622         return lldb::eSymbolTypeObjCClass;
623       if (name.starts_with("_OBJC_METACLASS_$_"))
624         return lldb::eSymbolTypeObjCMetaClass;
625       if (name.starts_with("_OBJC_IVAR_$_"))
626         return lldb::eSymbolTypeObjCIVar;
627     } else if (name.starts_with(".objc_class_name_")) {
628       // ObjC v1
629       return lldb::eSymbolTypeObjCClass;
630     }
631   }
632   return symbol_type_hint;
633 }
634 
635 std::vector<ObjectFile::LoadableData>
GetLoadableData(Target & target)636 ObjectFile::GetLoadableData(Target &target) {
637   std::vector<LoadableData> loadables;
638   SectionList *section_list = GetSectionList();
639   if (!section_list)
640     return loadables;
641   // Create a list of loadable data from loadable sections
642   size_t section_count = section_list->GetNumSections(0);
643   for (size_t i = 0; i < section_count; ++i) {
644     LoadableData loadable;
645     SectionSP section_sp = section_list->GetSectionAtIndex(i);
646     loadable.Dest =
647         target.GetSectionLoadList().GetSectionLoadAddress(section_sp);
648     if (loadable.Dest == LLDB_INVALID_ADDRESS)
649       continue;
650     // We can skip sections like bss
651     if (section_sp->GetFileSize() == 0)
652       continue;
653     DataExtractor section_data;
654     section_sp->GetSectionData(section_data);
655     loadable.Contents = llvm::ArrayRef<uint8_t>(section_data.GetDataStart(),
656                                                 section_data.GetByteSize());
657     loadables.push_back(loadable);
658   }
659   return loadables;
660 }
661 
CreateCallFrameInfo()662 std::unique_ptr<CallFrameInfo> ObjectFile::CreateCallFrameInfo() {
663   return {};
664 }
665 
RelocateSection(lldb_private::Section * section)666 void ObjectFile::RelocateSection(lldb_private::Section *section)
667 {
668 }
669 
MapFileData(const FileSpec & file,uint64_t Size,uint64_t Offset)670 DataBufferSP ObjectFile::MapFileData(const FileSpec &file, uint64_t Size,
671                                      uint64_t Offset) {
672   return FileSystem::Instance().CreateDataBuffer(file.GetPath(), Size, Offset);
673 }
674 
format(const ObjectFile::Type & type,raw_ostream & OS,StringRef Style)675 void llvm::format_provider<ObjectFile::Type>::format(
676     const ObjectFile::Type &type, raw_ostream &OS, StringRef Style) {
677   switch (type) {
678   case ObjectFile::eTypeInvalid:
679     OS << "invalid";
680     break;
681   case ObjectFile::eTypeCoreFile:
682     OS << "core file";
683     break;
684   case ObjectFile::eTypeExecutable:
685     OS << "executable";
686     break;
687   case ObjectFile::eTypeDebugInfo:
688     OS << "debug info";
689     break;
690   case ObjectFile::eTypeDynamicLinker:
691     OS << "dynamic linker";
692     break;
693   case ObjectFile::eTypeObjectFile:
694     OS << "object file";
695     break;
696   case ObjectFile::eTypeSharedLibrary:
697     OS << "shared library";
698     break;
699   case ObjectFile::eTypeStubLibrary:
700     OS << "stub library";
701     break;
702   case ObjectFile::eTypeJIT:
703     OS << "jit";
704     break;
705   case ObjectFile::eTypeUnknown:
706     OS << "unknown";
707     break;
708   }
709 }
710 
format(const ObjectFile::Strata & strata,raw_ostream & OS,StringRef Style)711 void llvm::format_provider<ObjectFile::Strata>::format(
712     const ObjectFile::Strata &strata, raw_ostream &OS, StringRef Style) {
713   switch (strata) {
714   case ObjectFile::eStrataInvalid:
715     OS << "invalid";
716     break;
717   case ObjectFile::eStrataUnknown:
718     OS << "unknown";
719     break;
720   case ObjectFile::eStrataUser:
721     OS << "user";
722     break;
723   case ObjectFile::eStrataKernel:
724     OS << "kernel";
725     break;
726   case ObjectFile::eStrataRawImage:
727     OS << "raw image";
728     break;
729   case ObjectFile::eStrataJIT:
730     OS << "jit";
731     break;
732   }
733 }
734 
735 
GetSymtab()736 Symtab *ObjectFile::GetSymtab() {
737   ModuleSP module_sp(GetModule());
738   if (module_sp) {
739     // We can't take the module lock in ObjectFile::GetSymtab() or we can
740     // deadlock in DWARF indexing when any file asks for the symbol table from
741     // an object file. This currently happens in the preloading of symbols in
742     // SymbolFileDWARF::PreloadSymbols() because the main thread will take the
743     // module lock, and then threads will be spun up to index the DWARF and
744     // any of those threads might end up trying to relocate items in the DWARF
745     // sections which causes ObjectFile::GetSectionData(...) to relocate section
746     // data which requires the symbol table.
747     //
748     // So to work around this, we create the symbol table one time using
749     // llvm::once_flag, lock it, and then set the unique pointer. Any other
750     // thread that gets ahold of the symbol table before parsing is done, will
751     // not be able to access the symbol table contents since all APIs in Symtab
752     // are protected by a mutex in the Symtab object itself.
753     llvm::call_once(*m_symtab_once_up, [&]() {
754       Symtab *symtab = new Symtab(this);
755       std::lock_guard<std::recursive_mutex> symtab_guard(symtab->GetMutex());
756       m_symtab_up.reset(symtab);
757       if (!m_symtab_up->LoadFromCache()) {
758         ElapsedTime elapsed(module_sp->GetSymtabParseTime());
759         ParseSymtab(*m_symtab_up);
760         m_symtab_up->Finalize();
761       }
762     });
763   }
764   return m_symtab_up.get();
765 }
766 
GetCacheHash()767 uint32_t ObjectFile::GetCacheHash() {
768   if (m_cache_hash)
769     return *m_cache_hash;
770   StreamString strm;
771   strm.Format("{0}-{1}-{2}", m_file, GetType(), GetStrata());
772   m_cache_hash = llvm::djbHash(strm.GetString());
773   return *m_cache_hash;
774 }
775 
776 namespace llvm {
777 namespace json {
778 
fromJSON(const llvm::json::Value & value,lldb_private::ObjectFile::Type & type,llvm::json::Path path)779 bool fromJSON(const llvm::json::Value &value,
780               lldb_private::ObjectFile::Type &type, llvm::json::Path path) {
781   if (auto str = value.getAsString()) {
782     type = llvm::StringSwitch<ObjectFile::Type>(*str)
783                .Case("corefile", ObjectFile::eTypeCoreFile)
784                .Case("executable", ObjectFile::eTypeExecutable)
785                .Case("debuginfo", ObjectFile::eTypeDebugInfo)
786                .Case("dynamiclinker", ObjectFile::eTypeDynamicLinker)
787                .Case("objectfile", ObjectFile::eTypeObjectFile)
788                .Case("sharedlibrary", ObjectFile::eTypeSharedLibrary)
789                .Case("stublibrary", ObjectFile::eTypeStubLibrary)
790                .Case("jit", ObjectFile::eTypeJIT)
791                .Case("unknown", ObjectFile::eTypeUnknown)
792                .Default(ObjectFile::eTypeInvalid);
793 
794     if (type == ObjectFile::eTypeInvalid) {
795       path.report("invalid object type");
796       return false;
797     }
798 
799     return true;
800   }
801   path.report("expected string");
802   return false;
803 }
804 } // namespace json
805 } // namespace llvm
806