1 //===-- ObjectFileMachO.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 "llvm/ADT/StringRef.h"
11 #include "llvm/Support/MachO.h"
12 
13 #include "ObjectFileMachO.h"
14 
15 #include "lldb/Core/ArchSpec.h"
16 #include "lldb/Core/DataBuffer.h"
17 #include "lldb/Host/FileSpec.h"
18 #include "lldb/Core/FileSpecList.h"
19 #include "lldb/Core/Module.h"
20 #include "lldb/Core/PluginManager.h"
21 #include "lldb/Core/Section.h"
22 #include "lldb/Core/StreamFile.h"
23 #include "lldb/Core/StreamString.h"
24 #include "lldb/Core/Timer.h"
25 #include "lldb/Core/UUID.h"
26 #include "lldb/Symbol/ClangNamespaceDecl.h"
27 #include "lldb/Symbol/ObjectFile.h"
28 
29 
30 using namespace lldb;
31 using namespace lldb_private;
32 using namespace llvm::MachO;
33 
34 #define MACHO_NLIST_ARM_SYMBOL_IS_THUMB 0x0008
35 
36 void
37 ObjectFileMachO::Initialize()
38 {
39     PluginManager::RegisterPlugin (GetPluginNameStatic(),
40                                    GetPluginDescriptionStatic(),
41                                    CreateInstance);
42 }
43 
44 void
45 ObjectFileMachO::Terminate()
46 {
47     PluginManager::UnregisterPlugin (CreateInstance);
48 }
49 
50 
51 const char *
52 ObjectFileMachO::GetPluginNameStatic()
53 {
54     return "object-file.mach-o";
55 }
56 
57 const char *
58 ObjectFileMachO::GetPluginDescriptionStatic()
59 {
60     return "Mach-o object file reader (32 and 64 bit)";
61 }
62 
63 
64 ObjectFile *
65 ObjectFileMachO::CreateInstance (Module* module, DataBufferSP& dataSP, const FileSpec* file, addr_t offset, addr_t length)
66 {
67     if (ObjectFileMachO::MagicBytesMatch(dataSP))
68     {
69         std::auto_ptr<ObjectFile> objfile_ap(new ObjectFileMachO (module, dataSP, file, offset, length));
70         if (objfile_ap.get() && objfile_ap->ParseHeader())
71             return objfile_ap.release();
72     }
73     return NULL;
74 }
75 
76 
77 static uint32_t
78 MachHeaderSizeFromMagic(uint32_t magic)
79 {
80     switch (magic)
81     {
82     case HeaderMagic32:
83     case HeaderMagic32Swapped:
84         return sizeof(struct mach_header);
85 
86     case HeaderMagic64:
87     case HeaderMagic64Swapped:
88         return sizeof(struct mach_header_64);
89         break;
90 
91     default:
92         break;
93     }
94     return 0;
95 }
96 
97 
98 bool
99 ObjectFileMachO::MagicBytesMatch (DataBufferSP& dataSP)
100 {
101     DataExtractor data(dataSP, lldb::endian::InlHostByteOrder(), 4);
102     uint32_t offset = 0;
103     uint32_t magic = data.GetU32(&offset);
104     return MachHeaderSizeFromMagic(magic) != 0;
105 }
106 
107 
108 ObjectFileMachO::ObjectFileMachO(Module* module, DataBufferSP& dataSP, const FileSpec* file, addr_t offset, addr_t length) :
109     ObjectFile(module, file, offset, length, dataSP),
110     m_mutex (Mutex::eMutexTypeRecursive),
111     m_header(),
112     m_sections_ap(),
113     m_symtab_ap(),
114     m_entry_point_address ()
115 {
116     ::memset (&m_header, 0, sizeof(m_header));
117     ::memset (&m_dysymtab, 0, sizeof(m_dysymtab));
118 }
119 
120 
121 ObjectFileMachO::~ObjectFileMachO()
122 {
123 }
124 
125 
126 bool
127 ObjectFileMachO::ParseHeader ()
128 {
129     lldb_private::Mutex::Locker locker(m_mutex);
130     bool can_parse = false;
131     uint32_t offset = 0;
132     m_data.SetByteOrder (lldb::endian::InlHostByteOrder());
133     // Leave magic in the original byte order
134     m_header.magic = m_data.GetU32(&offset);
135     switch (m_header.magic)
136     {
137     case HeaderMagic32:
138         m_data.SetByteOrder (lldb::endian::InlHostByteOrder());
139         m_data.SetAddressByteSize(4);
140         can_parse = true;
141         break;
142 
143     case HeaderMagic64:
144         m_data.SetByteOrder (lldb::endian::InlHostByteOrder());
145         m_data.SetAddressByteSize(8);
146         can_parse = true;
147         break;
148 
149     case HeaderMagic32Swapped:
150         m_data.SetByteOrder(lldb::endian::InlHostByteOrder() == eByteOrderBig ? eByteOrderLittle : eByteOrderBig);
151         m_data.SetAddressByteSize(4);
152         can_parse = true;
153         break;
154 
155     case HeaderMagic64Swapped:
156         m_data.SetByteOrder(lldb::endian::InlHostByteOrder() == eByteOrderBig ? eByteOrderLittle : eByteOrderBig);
157         m_data.SetAddressByteSize(8);
158         can_parse = true;
159         break;
160 
161     default:
162         break;
163     }
164 
165     if (can_parse)
166     {
167         m_data.GetU32(&offset, &m_header.cputype, 6);
168 
169         ArchSpec mach_arch(eArchTypeMachO, m_header.cputype, m_header.cpusubtype);
170 
171         if (SetModulesArchitecture (mach_arch))
172         {
173             // Read in all only the load command data
174             DataBufferSP data_sp(m_file.ReadFileContents(m_offset, m_header.sizeofcmds + MachHeaderSizeFromMagic(m_header.magic)));
175             m_data.SetData (data_sp);
176             return true;
177         }
178     }
179     else
180     {
181         memset(&m_header, 0, sizeof(struct mach_header));
182     }
183     return false;
184 }
185 
186 
187 ByteOrder
188 ObjectFileMachO::GetByteOrder () const
189 {
190     lldb_private::Mutex::Locker locker(m_mutex);
191     return m_data.GetByteOrder ();
192 }
193 
194 bool
195 ObjectFileMachO::IsExecutable() const
196 {
197     return m_header.filetype == HeaderFileTypeExecutable;
198 }
199 
200 size_t
201 ObjectFileMachO::GetAddressByteSize () const
202 {
203     lldb_private::Mutex::Locker locker(m_mutex);
204     return m_data.GetAddressByteSize ();
205 }
206 
207 AddressClass
208 ObjectFileMachO::GetAddressClass (lldb::addr_t file_addr)
209 {
210     Symtab *symtab = GetSymtab();
211     if (symtab)
212     {
213         Symbol *symbol = symtab->FindSymbolContainingFileAddress(file_addr);
214         if (symbol)
215         {
216             const AddressRange *range_ptr = symbol->GetAddressRangePtr();
217             if (range_ptr)
218             {
219                 const Section *section = range_ptr->GetBaseAddress().GetSection();
220                 if (section)
221                 {
222                     const SectionType section_type = section->GetType();
223                     switch (section_type)
224                     {
225                     case eSectionTypeInvalid:               return eAddressClassUnknown;
226                     case eSectionTypeCode:
227                         if (m_header.cputype == llvm::MachO::CPUTypeARM)
228                         {
229                             // For ARM we have a bit in the n_desc field of the symbol
230                             // that tells us ARM/Thumb which is bit 0x0008.
231                             if (symbol->GetFlags() & MACHO_NLIST_ARM_SYMBOL_IS_THUMB)
232                                 return eAddressClassCodeAlternateISA;
233                         }
234                         return eAddressClassCode;
235 
236                     case eSectionTypeContainer:             return eAddressClassUnknown;
237                     case eSectionTypeData:
238                     case eSectionTypeDataCString:
239                     case eSectionTypeDataCStringPointers:
240                     case eSectionTypeDataSymbolAddress:
241                     case eSectionTypeData4:
242                     case eSectionTypeData8:
243                     case eSectionTypeData16:
244                     case eSectionTypeDataPointers:
245                     case eSectionTypeZeroFill:
246                     case eSectionTypeDataObjCMessageRefs:
247                     case eSectionTypeDataObjCCFStrings:
248                         return eAddressClassData;
249                     case eSectionTypeDebug:
250                     case eSectionTypeDWARFDebugAbbrev:
251                     case eSectionTypeDWARFDebugAranges:
252                     case eSectionTypeDWARFDebugFrame:
253                     case eSectionTypeDWARFDebugInfo:
254                     case eSectionTypeDWARFDebugLine:
255                     case eSectionTypeDWARFDebugLoc:
256                     case eSectionTypeDWARFDebugMacInfo:
257                     case eSectionTypeDWARFDebugPubNames:
258                     case eSectionTypeDWARFDebugPubTypes:
259                     case eSectionTypeDWARFDebugRanges:
260                     case eSectionTypeDWARFDebugStr:
261                     case eSectionTypeDWARFAppleNames:
262                     case eSectionTypeDWARFAppleTypes:
263                     case eSectionTypeDWARFAppleNamespaces:
264                     case eSectionTypeDWARFAppleObjC:
265                         return eAddressClassDebug;
266                     case eSectionTypeEHFrame:               return eAddressClassRuntime;
267                     case eSectionTypeOther:                 return eAddressClassUnknown;
268                     }
269                 }
270             }
271 
272             const SymbolType symbol_type = symbol->GetType();
273             switch (symbol_type)
274             {
275             case eSymbolTypeAny:            return eAddressClassUnknown;
276             case eSymbolTypeAbsolute:       return eAddressClassUnknown;
277 
278             case eSymbolTypeCode:
279             case eSymbolTypeTrampoline:
280                 if (m_header.cputype == llvm::MachO::CPUTypeARM)
281                 {
282                     // For ARM we have a bit in the n_desc field of the symbol
283                     // that tells us ARM/Thumb which is bit 0x0008.
284                     if (symbol->GetFlags() & MACHO_NLIST_ARM_SYMBOL_IS_THUMB)
285                         return eAddressClassCodeAlternateISA;
286                 }
287                 return eAddressClassCode;
288 
289             case eSymbolTypeData:           return eAddressClassData;
290             case eSymbolTypeRuntime:        return eAddressClassRuntime;
291             case eSymbolTypeException:      return eAddressClassRuntime;
292             case eSymbolTypeSourceFile:     return eAddressClassDebug;
293             case eSymbolTypeHeaderFile:     return eAddressClassDebug;
294             case eSymbolTypeObjectFile:     return eAddressClassDebug;
295             case eSymbolTypeCommonBlock:    return eAddressClassDebug;
296             case eSymbolTypeBlock:          return eAddressClassDebug;
297             case eSymbolTypeLocal:          return eAddressClassData;
298             case eSymbolTypeParam:          return eAddressClassData;
299             case eSymbolTypeVariable:       return eAddressClassData;
300             case eSymbolTypeVariableType:   return eAddressClassDebug;
301             case eSymbolTypeLineEntry:      return eAddressClassDebug;
302             case eSymbolTypeLineHeader:     return eAddressClassDebug;
303             case eSymbolTypeScopeBegin:     return eAddressClassDebug;
304             case eSymbolTypeScopeEnd:       return eAddressClassDebug;
305             case eSymbolTypeAdditional:     return eAddressClassUnknown;
306             case eSymbolTypeCompiler:       return eAddressClassDebug;
307             case eSymbolTypeInstrumentation:return eAddressClassDebug;
308             case eSymbolTypeUndefined:      return eAddressClassUnknown;
309             case eSymbolTypeObjCClass:      return eAddressClassRuntime;
310             case eSymbolTypeObjCMetaClass:  return eAddressClassRuntime;
311             case eSymbolTypeObjCIVar:       return eAddressClassRuntime;
312             }
313         }
314     }
315     return eAddressClassUnknown;
316 }
317 
318 Symtab *
319 ObjectFileMachO::GetSymtab()
320 {
321     lldb_private::Mutex::Locker symfile_locker(m_mutex);
322     if (m_symtab_ap.get() == NULL)
323     {
324         m_symtab_ap.reset(new Symtab(this));
325         Mutex::Locker symtab_locker (m_symtab_ap->GetMutex());
326         ParseSymtab (true);
327         m_symtab_ap->Finalize ();
328     }
329     return m_symtab_ap.get();
330 }
331 
332 
333 SectionList *
334 ObjectFileMachO::GetSectionList()
335 {
336     lldb_private::Mutex::Locker locker(m_mutex);
337     if (m_sections_ap.get() == NULL)
338     {
339         m_sections_ap.reset(new SectionList());
340         ParseSections();
341     }
342     return m_sections_ap.get();
343 }
344 
345 
346 size_t
347 ObjectFileMachO::ParseSections ()
348 {
349     lldb::user_id_t segID = 0;
350     lldb::user_id_t sectID = 0;
351     struct segment_command_64 load_cmd;
352     uint32_t offset = MachHeaderSizeFromMagic(m_header.magic);
353     uint32_t i;
354     //bool dump_sections = false;
355     for (i=0; i<m_header.ncmds; ++i)
356     {
357         const uint32_t load_cmd_offset = offset;
358         if (m_data.GetU32(&offset, &load_cmd, 2) == NULL)
359             break;
360 
361         if (load_cmd.cmd == LoadCommandSegment32 || load_cmd.cmd == LoadCommandSegment64)
362         {
363             if (m_data.GetU8(&offset, (uint8_t*)load_cmd.segname, 16))
364             {
365                 load_cmd.vmaddr = m_data.GetAddress(&offset);
366                 load_cmd.vmsize = m_data.GetAddress(&offset);
367                 load_cmd.fileoff = m_data.GetAddress(&offset);
368                 load_cmd.filesize = m_data.GetAddress(&offset);
369                 if (m_data.GetU32(&offset, &load_cmd.maxprot, 4))
370                 {
371 
372                     const bool segment_is_encrypted = (load_cmd.flags & SegmentCommandFlagBitProtectedVersion1) != 0;
373 
374                     // Keep a list of mach segments around in case we need to
375                     // get at data that isn't stored in the abstracted Sections.
376                     m_mach_segments.push_back (load_cmd);
377 
378                     ConstString segment_name (load_cmd.segname, std::min<int>(strlen(load_cmd.segname), sizeof(load_cmd.segname)));
379                     // Use a segment ID of the segment index shifted left by 8 so they
380                     // never conflict with any of the sections.
381                     SectionSP segment_sp;
382                     if (segment_name)
383                     {
384                         segment_sp.reset(new Section (NULL,
385                                                       GetModule(),            // Module to which this section belongs
386                                                       ++segID << 8,           // Section ID is the 1 based segment index shifted right by 8 bits as not to collide with any of the 256 section IDs that are possible
387                                                       segment_name,           // Name of this section
388                                                       eSectionTypeContainer,  // This section is a container of other sections.
389                                                       load_cmd.vmaddr,        // File VM address == addresses as they are found in the object file
390                                                       load_cmd.vmsize,        // VM size in bytes of this section
391                                                       load_cmd.fileoff,       // Offset to the data for this section in the file
392                                                       load_cmd.filesize,      // Size in bytes of this section as found in the the file
393                                                       load_cmd.flags));       // Flags for this section
394 
395                         segment_sp->SetIsEncrypted (segment_is_encrypted);
396                         m_sections_ap->AddSection(segment_sp);
397                     }
398 
399                     struct section_64 sect64;
400                     ::memset (&sect64, 0, sizeof(sect64));
401                     // Push a section into our mach sections for the section at
402                     // index zero (NListSectionNoSection) if we don't have any
403                     // mach sections yet...
404                     if (m_mach_sections.empty())
405                         m_mach_sections.push_back(sect64);
406                     uint32_t segment_sect_idx;
407                     const lldb::user_id_t first_segment_sectID = sectID + 1;
408 
409 
410                     const uint32_t num_u32s = load_cmd.cmd == LoadCommandSegment32 ? 7 : 8;
411                     for (segment_sect_idx=0; segment_sect_idx<load_cmd.nsects; ++segment_sect_idx)
412                     {
413                         if (m_data.GetU8(&offset, (uint8_t*)sect64.sectname, sizeof(sect64.sectname)) == NULL)
414                             break;
415                         if (m_data.GetU8(&offset, (uint8_t*)sect64.segname, sizeof(sect64.segname)) == NULL)
416                             break;
417                         sect64.addr = m_data.GetAddress(&offset);
418                         sect64.size = m_data.GetAddress(&offset);
419 
420                         if (m_data.GetU32(&offset, &sect64.offset, num_u32s) == NULL)
421                             break;
422 
423                         // Keep a list of mach sections around in case we need to
424                         // get at data that isn't stored in the abstracted Sections.
425                         m_mach_sections.push_back (sect64);
426 
427                         ConstString section_name (sect64.sectname, std::min<size_t>(strlen(sect64.sectname), sizeof(sect64.sectname)));
428                         if (!segment_name)
429                         {
430                             // We have a segment with no name so we need to conjure up
431                             // segments that correspond to the section's segname if there
432                             // isn't already such a section. If there is such a section,
433                             // we resize the section so that it spans all sections.
434                             // We also mark these sections as fake so address matches don't
435                             // hit if they land in the gaps between the child sections.
436                             segment_name.SetTrimmedCStringWithLength(sect64.segname, sizeof(sect64.segname));
437                             segment_sp = m_sections_ap->FindSectionByName (segment_name);
438                             if (segment_sp.get())
439                             {
440                                 Section *segment = segment_sp.get();
441                                 // Grow the section size as needed.
442                                 const lldb::addr_t sect64_min_addr = sect64.addr;
443                                 const lldb::addr_t sect64_max_addr = sect64_min_addr + sect64.size;
444                                 const lldb::addr_t curr_seg_byte_size = segment->GetByteSize();
445                                 const lldb::addr_t curr_seg_min_addr = segment->GetFileAddress();
446                                 const lldb::addr_t curr_seg_max_addr = curr_seg_min_addr + curr_seg_byte_size;
447                                 if (sect64_min_addr >= curr_seg_min_addr)
448                                 {
449                                     const lldb::addr_t new_seg_byte_size = sect64_max_addr - curr_seg_min_addr;
450                                     // Only grow the section size if needed
451                                     if (new_seg_byte_size > curr_seg_byte_size)
452                                         segment->SetByteSize (new_seg_byte_size);
453                                 }
454                                 else
455                                 {
456                                     // We need to change the base address of the segment and
457                                     // adjust the child section offsets for all existing children.
458                                     const lldb::addr_t slide_amount = sect64_min_addr - curr_seg_min_addr;
459                                     segment->Slide(slide_amount, false);
460                                     segment->GetChildren().Slide (-slide_amount, false);
461                                     segment->SetByteSize (curr_seg_max_addr - sect64_min_addr);
462                                 }
463 
464                                 // Grow the section size as needed.
465                                 if (sect64.offset)
466                                 {
467                                     const lldb::addr_t segment_min_file_offset = segment->GetFileOffset();
468                                     const lldb::addr_t segment_max_file_offset = segment_min_file_offset + segment->GetFileSize();
469 
470                                     const lldb::addr_t section_min_file_offset = sect64.offset;
471                                     const lldb::addr_t section_max_file_offset = section_min_file_offset + sect64.size;
472                                     const lldb::addr_t new_file_offset = std::min (section_min_file_offset, segment_min_file_offset);
473                                     const lldb::addr_t new_file_size = std::max (section_max_file_offset, segment_max_file_offset) - new_file_offset;
474                                     segment->SetFileOffset (new_file_offset);
475                                     segment->SetFileSize (new_file_size);
476                                 }
477                             }
478                             else
479                             {
480                                 // Create a fake section for the section's named segment
481                                 segment_sp.reset(new Section(segment_sp.get(),       // Parent section
482                                                              GetModule(),            // Module to which this section belongs
483                                                              ++segID << 8,           // Section ID is the 1 based segment index shifted right by 8 bits as not to collide with any of the 256 section IDs that are possible
484                                                              segment_name,           // Name of this section
485                                                              eSectionTypeContainer,  // This section is a container of other sections.
486                                                              sect64.addr,            // File VM address == addresses as they are found in the object file
487                                                              sect64.size,            // VM size in bytes of this section
488                                                              sect64.offset,          // Offset to the data for this section in the file
489                                                              sect64.offset ? sect64.size : 0,        // Size in bytes of this section as found in the the file
490                                                              load_cmd.flags));       // Flags for this section
491                                 segment_sp->SetIsFake(true);
492                                 m_sections_ap->AddSection(segment_sp);
493                                 segment_sp->SetIsEncrypted (segment_is_encrypted);
494                             }
495                         }
496                         assert (segment_sp.get());
497 
498                         uint32_t mach_sect_type = sect64.flags & SectionFlagMaskSectionType;
499                         static ConstString g_sect_name_objc_data ("__objc_data");
500                         static ConstString g_sect_name_objc_msgrefs ("__objc_msgrefs");
501                         static ConstString g_sect_name_objc_selrefs ("__objc_selrefs");
502                         static ConstString g_sect_name_objc_classrefs ("__objc_classrefs");
503                         static ConstString g_sect_name_objc_superrefs ("__objc_superrefs");
504                         static ConstString g_sect_name_objc_const ("__objc_const");
505                         static ConstString g_sect_name_objc_classlist ("__objc_classlist");
506                         static ConstString g_sect_name_cfstring ("__cfstring");
507 
508                         static ConstString g_sect_name_dwarf_debug_abbrev ("__debug_abbrev");
509                         static ConstString g_sect_name_dwarf_debug_aranges ("__debug_aranges");
510                         static ConstString g_sect_name_dwarf_debug_frame ("__debug_frame");
511                         static ConstString g_sect_name_dwarf_debug_info ("__debug_info");
512                         static ConstString g_sect_name_dwarf_debug_line ("__debug_line");
513                         static ConstString g_sect_name_dwarf_debug_loc ("__debug_loc");
514                         static ConstString g_sect_name_dwarf_debug_macinfo ("__debug_macinfo");
515                         static ConstString g_sect_name_dwarf_debug_pubnames ("__debug_pubnames");
516                         static ConstString g_sect_name_dwarf_debug_pubtypes ("__debug_pubtypes");
517                         static ConstString g_sect_name_dwarf_debug_ranges ("__debug_ranges");
518                         static ConstString g_sect_name_dwarf_debug_str ("__debug_str");
519                         static ConstString g_sect_name_dwarf_apple_names ("__apple_names");
520                         static ConstString g_sect_name_dwarf_apple_types ("__apple_types");
521                         static ConstString g_sect_name_dwarf_apple_namespaces ("__apple_namespac");
522                         static ConstString g_sect_name_dwarf_apple_objc ("__apple_objc");
523                         static ConstString g_sect_name_eh_frame ("__eh_frame");
524                         static ConstString g_sect_name_DATA ("__DATA");
525                         static ConstString g_sect_name_TEXT ("__TEXT");
526 
527                         SectionType sect_type = eSectionTypeOther;
528 
529                         if (section_name == g_sect_name_dwarf_debug_abbrev)
530                             sect_type = eSectionTypeDWARFDebugAbbrev;
531                         else if (section_name == g_sect_name_dwarf_debug_aranges)
532                             sect_type = eSectionTypeDWARFDebugAranges;
533                         else if (section_name == g_sect_name_dwarf_debug_frame)
534                             sect_type = eSectionTypeDWARFDebugFrame;
535                         else if (section_name == g_sect_name_dwarf_debug_info)
536                             sect_type = eSectionTypeDWARFDebugInfo;
537                         else if (section_name == g_sect_name_dwarf_debug_line)
538                             sect_type = eSectionTypeDWARFDebugLine;
539                         else if (section_name == g_sect_name_dwarf_debug_loc)
540                             sect_type = eSectionTypeDWARFDebugLoc;
541                         else if (section_name == g_sect_name_dwarf_debug_macinfo)
542                             sect_type = eSectionTypeDWARFDebugMacInfo;
543                         else if (section_name == g_sect_name_dwarf_debug_pubnames)
544                             sect_type = eSectionTypeDWARFDebugPubNames;
545                         else if (section_name == g_sect_name_dwarf_debug_pubtypes)
546                             sect_type = eSectionTypeDWARFDebugPubTypes;
547                         else if (section_name == g_sect_name_dwarf_debug_ranges)
548                             sect_type = eSectionTypeDWARFDebugRanges;
549                         else if (section_name == g_sect_name_dwarf_debug_str)
550                             sect_type = eSectionTypeDWARFDebugStr;
551                         else if (section_name == g_sect_name_dwarf_apple_names)
552                             sect_type = eSectionTypeDWARFAppleNames;
553                         else if (section_name == g_sect_name_dwarf_apple_types)
554                             sect_type = eSectionTypeDWARFAppleTypes;
555                         else if (section_name == g_sect_name_dwarf_apple_namespaces)
556                             sect_type = eSectionTypeDWARFAppleNamespaces;
557                         else if (section_name == g_sect_name_dwarf_apple_objc)
558                             sect_type = eSectionTypeDWARFAppleObjC;
559                         else if (section_name == g_sect_name_objc_selrefs)
560                             sect_type = eSectionTypeDataCStringPointers;
561                         else if (section_name == g_sect_name_objc_msgrefs)
562                             sect_type = eSectionTypeDataObjCMessageRefs;
563                         else if (section_name == g_sect_name_eh_frame)
564                             sect_type = eSectionTypeEHFrame;
565                         else if (section_name == g_sect_name_cfstring)
566                             sect_type = eSectionTypeDataObjCCFStrings;
567                         else if (section_name == g_sect_name_objc_data ||
568                                  section_name == g_sect_name_objc_classrefs ||
569                                  section_name == g_sect_name_objc_superrefs ||
570                                  section_name == g_sect_name_objc_const ||
571                                  section_name == g_sect_name_objc_classlist)
572                         {
573                             sect_type = eSectionTypeDataPointers;
574                         }
575 
576                         if (sect_type == eSectionTypeOther)
577                         {
578                             switch (mach_sect_type)
579                             {
580                             // TODO: categorize sections by other flags for regular sections
581                             case SectionTypeRegular:
582                                 if (segment_sp->GetName() == g_sect_name_TEXT)
583                                     sect_type = eSectionTypeCode;
584                                 else if (segment_sp->GetName() == g_sect_name_DATA)
585                                     sect_type = eSectionTypeData;
586                                 else
587                                     sect_type = eSectionTypeOther;
588                                 break;
589                             case SectionTypeZeroFill:                   sect_type = eSectionTypeZeroFill; break;
590                             case SectionTypeCStringLiterals:            sect_type = eSectionTypeDataCString;    break; // section with only literal C strings
591                             case SectionType4ByteLiterals:              sect_type = eSectionTypeData4;    break; // section with only 4 byte literals
592                             case SectionType8ByteLiterals:              sect_type = eSectionTypeData8;    break; // section with only 8 byte literals
593                             case SectionTypeLiteralPointers:            sect_type = eSectionTypeDataPointers;  break; // section with only pointers to literals
594                             case SectionTypeNonLazySymbolPointers:      sect_type = eSectionTypeDataPointers;  break; // section with only non-lazy symbol pointers
595                             case SectionTypeLazySymbolPointers:         sect_type = eSectionTypeDataPointers;  break; // section with only lazy symbol pointers
596                             case SectionTypeSymbolStubs:                sect_type = eSectionTypeCode;  break; // section with only symbol stubs, byte size of stub in the reserved2 field
597                             case SectionTypeModuleInitFunctionPointers: sect_type = eSectionTypeDataPointers;    break; // section with only function pointers for initialization
598                             case SectionTypeModuleTermFunctionPointers: sect_type = eSectionTypeDataPointers; break; // section with only function pointers for termination
599                             case SectionTypeCoalesced:                  sect_type = eSectionTypeOther; break;
600                             case SectionTypeZeroFillLarge:              sect_type = eSectionTypeZeroFill; break;
601                             case SectionTypeInterposing:                sect_type = eSectionTypeCode;  break; // section with only pairs of function pointers for interposing
602                             case SectionType16ByteLiterals:             sect_type = eSectionTypeData16; break; // section with only 16 byte literals
603                             case SectionTypeDTraceObjectFormat:         sect_type = eSectionTypeDebug; break;
604                             case SectionTypeLazyDylibSymbolPointers:    sect_type = eSectionTypeDataPointers;  break;
605                             default: break;
606                             }
607                         }
608 
609                         SectionSP section_sp(new Section(segment_sp.get(),
610                                                          GetModule(),
611                                                          ++sectID,
612                                                          section_name,
613                                                          sect_type,
614                                                          sect64.addr - segment_sp->GetFileAddress(),
615                                                          sect64.size,
616                                                          sect64.offset,
617                                                          sect64.offset == 0 ? 0 : sect64.size,
618                                                          sect64.flags));
619                         // Set the section to be encrypted to match the segment
620                         section_sp->SetIsEncrypted (segment_is_encrypted);
621 
622                         segment_sp->GetChildren().AddSection(section_sp);
623 
624                         if (segment_sp->IsFake())
625                         {
626                             segment_sp.reset();
627                             segment_name.Clear();
628                         }
629                     }
630                     if (segment_sp && m_header.filetype == HeaderFileTypeDSYM)
631                     {
632                         if (first_segment_sectID <= sectID)
633                         {
634                             lldb::user_id_t sect_uid;
635                             for (sect_uid = first_segment_sectID; sect_uid <= sectID; ++sect_uid)
636                             {
637                                 SectionSP curr_section_sp(segment_sp->GetChildren().FindSectionByID (sect_uid));
638                                 SectionSP next_section_sp;
639                                 if (sect_uid + 1 <= sectID)
640                                     next_section_sp = segment_sp->GetChildren().FindSectionByID (sect_uid+1);
641 
642                                 if (curr_section_sp.get())
643                                 {
644                                     if (curr_section_sp->GetByteSize() == 0)
645                                     {
646                                         if (next_section_sp.get() != NULL)
647                                             curr_section_sp->SetByteSize ( next_section_sp->GetFileAddress() - curr_section_sp->GetFileAddress() );
648                                         else
649                                             curr_section_sp->SetByteSize ( load_cmd.vmsize );
650                                     }
651                                 }
652                             }
653                         }
654                     }
655                 }
656             }
657         }
658         else if (load_cmd.cmd == LoadCommandDynamicSymtabInfo)
659         {
660             m_dysymtab.cmd = load_cmd.cmd;
661             m_dysymtab.cmdsize = load_cmd.cmdsize;
662             m_data.GetU32 (&offset, &m_dysymtab.ilocalsym, (sizeof(m_dysymtab) / sizeof(uint32_t)) - 2);
663         }
664 
665         offset = load_cmd_offset + load_cmd.cmdsize;
666     }
667 //    if (dump_sections)
668 //    {
669 //        StreamFile s(stdout);
670 //        m_sections_ap->Dump(&s, true);
671 //    }
672     return sectID;  // Return the number of sections we registered with the module
673 }
674 
675 class MachSymtabSectionInfo
676 {
677 public:
678 
679     MachSymtabSectionInfo (SectionList *section_list) :
680         m_section_list (section_list),
681         m_section_infos()
682     {
683         // Get the number of sections down to a depth of 1 to include
684         // all segments and their sections, but no other sections that
685         // may be added for debug map or
686         m_section_infos.resize(section_list->GetNumSections(1));
687     }
688 
689 
690     Section *
691     GetSection (uint8_t n_sect, addr_t file_addr)
692     {
693         if (n_sect == 0)
694             return NULL;
695         if (n_sect < m_section_infos.size())
696         {
697             if (m_section_infos[n_sect].section == NULL)
698             {
699                 Section *section = m_section_list->FindSectionByID (n_sect).get();
700                 m_section_infos[n_sect].section = section;
701                 if (section != NULL)
702                 {
703                     m_section_infos[n_sect].vm_range.SetBaseAddress (section->GetFileAddress());
704                     m_section_infos[n_sect].vm_range.SetByteSize (section->GetByteSize());
705                 }
706                 else
707                 {
708                     fprintf (stderr, "error: unable to find section for section %u\n", n_sect);
709                 }
710             }
711             if (m_section_infos[n_sect].vm_range.Contains(file_addr))
712             {
713                 // Symbol is in section.
714                 return m_section_infos[n_sect].section;
715             }
716             else if (m_section_infos[n_sect].vm_range.GetByteSize () == 0 &&
717                      m_section_infos[n_sect].vm_range.GetBaseAddress() == file_addr)
718             {
719                 // Symbol is in section with zero size, but has the same start
720                 // address as the section. This can happen with linker symbols
721                 // (symbols that start with the letter 'l' or 'L'.
722                 return m_section_infos[n_sect].section;
723             }
724         }
725         return m_section_list->FindSectionContainingFileAddress(file_addr).get();
726     }
727 
728 protected:
729     struct SectionInfo
730     {
731         SectionInfo () :
732             vm_range(),
733             section (NULL)
734         {
735         }
736 
737         VMRange vm_range;
738         Section *section;
739     };
740     SectionList *m_section_list;
741     std::vector<SectionInfo> m_section_infos;
742 };
743 
744 
745 
746 size_t
747 ObjectFileMachO::ParseSymtab (bool minimize)
748 {
749     Timer scoped_timer(__PRETTY_FUNCTION__,
750                        "ObjectFileMachO::ParseSymtab () module = %s",
751                        m_file.GetFilename().AsCString(""));
752     struct symtab_command symtab_load_command;
753     uint32_t offset = MachHeaderSizeFromMagic(m_header.magic);
754     uint32_t i;
755     for (i=0; i<m_header.ncmds; ++i)
756     {
757         const uint32_t cmd_offset = offset;
758         // Read in the load command and load command size
759         if (m_data.GetU32(&offset, &symtab_load_command, 2) == NULL)
760             break;
761         // Watch for the symbol table load command
762         if (symtab_load_command.cmd == LoadCommandSymtab)
763         {
764             // Read in the rest of the symtab load command
765             if (m_data.GetU32(&offset, &symtab_load_command.symoff, 4)) // fill in symoff, nsyms, stroff, strsize fields
766             {
767                 Symtab *symtab = m_symtab_ap.get();
768                 SectionList *section_list = GetSectionList();
769                 assert(section_list);
770                 const size_t addr_size = m_data.GetAddressByteSize();
771                 const ByteOrder endian = m_data.GetByteOrder();
772                 bool bit_width_32 = addr_size == 4;
773                 const size_t nlist_size = bit_width_32 ? sizeof(struct nlist) : sizeof(struct nlist_64);
774 
775                 DataBufferSP symtab_data_sp(m_file.ReadFileContents(m_offset + symtab_load_command.symoff, symtab_load_command.nsyms * nlist_size));
776                 DataBufferSP strtab_data_sp(m_file.ReadFileContents(m_offset + symtab_load_command.stroff, symtab_load_command.strsize));
777 
778                 const char *strtab_data = (const char *)strtab_data_sp->GetBytes();
779                 const size_t strtab_data_len = strtab_data_sp->GetByteSize();
780 
781                 static ConstString g_segment_name_TEXT ("__TEXT");
782                 static ConstString g_segment_name_DATA ("__DATA");
783                 static ConstString g_segment_name_OBJC ("__OBJC");
784                 static ConstString g_section_name_eh_frame ("__eh_frame");
785                 SectionSP text_section_sp(section_list->FindSectionByName(g_segment_name_TEXT));
786                 SectionSP data_section_sp(section_list->FindSectionByName(g_segment_name_DATA));
787                 SectionSP objc_section_sp(section_list->FindSectionByName(g_segment_name_OBJC));
788                 SectionSP eh_frame_section_sp;
789                 if (text_section_sp.get())
790                     eh_frame_section_sp = text_section_sp->GetChildren().FindSectionByName (g_section_name_eh_frame);
791                 else
792                     eh_frame_section_sp = section_list->FindSectionByName (g_section_name_eh_frame);
793 
794                 uint8_t TEXT_eh_frame_sectID = eh_frame_section_sp.get() ? eh_frame_section_sp->GetID() : NListSectionNoSection;
795                 //uint32_t symtab_offset = 0;
796                 const uint8_t* nlist_data = symtab_data_sp->GetBytes();
797                 assert (symtab_data_sp->GetByteSize()/nlist_size >= symtab_load_command.nsyms);
798 
799 
800                 if (endian != lldb::endian::InlHostByteOrder())
801                 {
802                     // ...
803                     assert (!"UNIMPLEMENTED: Swap all nlist entries");
804                 }
805                 uint32_t N_SO_index = UINT32_MAX;
806 
807                 MachSymtabSectionInfo section_info (section_list);
808                 std::vector<uint32_t> N_FUN_indexes;
809                 std::vector<uint32_t> N_NSYM_indexes;
810                 std::vector<uint32_t> N_INCL_indexes;
811                 std::vector<uint32_t> N_BRAC_indexes;
812                 std::vector<uint32_t> N_COMM_indexes;
813                 typedef std::map <uint64_t, uint32_t> ValueToSymbolIndexMap;
814                 typedef std::map <uint32_t, uint32_t> NListIndexToSymbolIndexMap;
815                 ValueToSymbolIndexMap N_FUN_addr_to_sym_idx;
816                 ValueToSymbolIndexMap N_STSYM_addr_to_sym_idx;
817                 // Any symbols that get merged into another will get an entry
818                 // in this map so we know
819                 NListIndexToSymbolIndexMap m_nlist_idx_to_sym_idx;
820                 uint32_t nlist_idx = 0;
821                 Symbol *symbol_ptr = NULL;
822 
823                 uint32_t sym_idx = 0;
824                 Symbol *sym = symtab->Resize (symtab_load_command.nsyms + m_dysymtab.nindirectsyms);
825                 uint32_t num_syms = symtab->GetNumSymbols();
826 
827                 //symtab->Reserve (symtab_load_command.nsyms + m_dysymtab.nindirectsyms);
828                 for (nlist_idx = 0; nlist_idx < symtab_load_command.nsyms; ++nlist_idx)
829                 {
830                     struct nlist_64 nlist;
831                     if (bit_width_32)
832                     {
833                         struct nlist* nlist32_ptr = (struct nlist*)(nlist_data + (nlist_idx * nlist_size));
834                         nlist.n_strx = nlist32_ptr->n_strx;
835                         nlist.n_type = nlist32_ptr->n_type;
836                         nlist.n_sect = nlist32_ptr->n_sect;
837                         nlist.n_desc = nlist32_ptr->n_desc;
838                         nlist.n_value = nlist32_ptr->n_value;
839                     }
840                     else
841                     {
842                         nlist = *((struct nlist_64*)(nlist_data + (nlist_idx * nlist_size)));
843                     }
844 
845                     SymbolType type = eSymbolTypeInvalid;
846                     if (nlist.n_strx >= strtab_data_len)
847                     {
848                         // No symbol should be NULL, even the symbols with no
849                         // string values should have an offset zero which points
850                         // to an empty C-string
851                         fprintf (stderr,
852                                  "error: symbol[%u] has invalid string table offset 0x%x in %s/%s, ignoring symbol\n",
853                                  nlist_idx,
854                                  nlist.n_strx,
855                                  m_module->GetFileSpec().GetDirectory().GetCString(),
856                                  m_module->GetFileSpec().GetFilename().GetCString());
857                         continue;
858                     }
859                     const char *symbol_name = &strtab_data[nlist.n_strx];
860                     const char *symbol_name_non_abi_mangled = NULL;
861 
862                     if (symbol_name[0] == '\0')
863                         symbol_name = NULL;
864                     Section* symbol_section = NULL;
865                     bool add_nlist = true;
866                     bool is_debug = ((nlist.n_type & NlistMaskStab) != 0);
867 
868                     assert (sym_idx < num_syms);
869 
870                     sym[sym_idx].SetDebug (is_debug);
871 
872                     if (is_debug)
873                     {
874                         switch (nlist.n_type)
875                         {
876                         case StabGlobalSymbol:
877                             // N_GSYM -- global symbol: name,,NO_SECT,type,0
878                             // Sometimes the N_GSYM value contains the address.
879                             sym[sym_idx].SetExternal(true);
880                             if (nlist.n_value != 0)
881                                 symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
882                             type = eSymbolTypeData;
883                             break;
884 
885                         case StabFunctionName:
886                             // N_FNAME -- procedure name (f77 kludge): name,,NO_SECT,0,0
887                             type = eSymbolTypeCompiler;
888                             break;
889 
890                         case StabFunction:
891                             // N_FUN -- procedure: name,,n_sect,linenumber,address
892                             if (symbol_name)
893                             {
894                                 type = eSymbolTypeCode;
895                                 symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
896 
897                                 N_FUN_addr_to_sym_idx[nlist.n_value] = sym_idx;
898                                 // We use the current number of symbols in the symbol table in lieu of
899                                 // using nlist_idx in case we ever start trimming entries out
900                                 N_FUN_indexes.push_back(sym_idx);
901                             }
902                             else
903                             {
904                                 type = eSymbolTypeCompiler;
905 
906                                 if ( !N_FUN_indexes.empty() )
907                                 {
908                                     // Copy the size of the function into the original STAB entry so we don't have
909                                     // to hunt for it later
910                                     symtab->SymbolAtIndex(N_FUN_indexes.back())->SetByteSize(nlist.n_value);
911                                     N_FUN_indexes.pop_back();
912                                     // We don't really need the end function STAB as it contains the size which
913                                     // we already placed with the original symbol, so don't add it if we want a
914                                     // minimal symbol table
915                                     if (minimize)
916                                         add_nlist = false;
917                                 }
918                             }
919                             break;
920 
921                         case StabStaticSymbol:
922                             // N_STSYM -- static symbol: name,,n_sect,type,address
923                             N_STSYM_addr_to_sym_idx[nlist.n_value] = sym_idx;
924                             symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
925                             type = eSymbolTypeData;
926                             break;
927 
928                         case StabLocalCommon:
929                             // N_LCSYM -- .lcomm symbol: name,,n_sect,type,address
930                             symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
931                             type = eSymbolTypeCommonBlock;
932                             break;
933 
934                         case StabBeginSymbol:
935                             // N_BNSYM
936                             // We use the current number of symbols in the symbol table in lieu of
937                             // using nlist_idx in case we ever start trimming entries out
938                             if (minimize)
939                             {
940                                 // Skip these if we want minimal symbol tables
941                                 add_nlist = false;
942                             }
943                             else
944                             {
945                                 symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
946                                 N_NSYM_indexes.push_back(sym_idx);
947                                 type = eSymbolTypeScopeBegin;
948                             }
949                             break;
950 
951                         case StabEndSymbol:
952                             // N_ENSYM
953                             // Set the size of the N_BNSYM to the terminating index of this N_ENSYM
954                             // so that we can always skip the entire symbol if we need to navigate
955                             // more quickly at the source level when parsing STABS
956                             if (minimize)
957                             {
958                                 // Skip these if we want minimal symbol tables
959                                 add_nlist = false;
960                             }
961                             else
962                             {
963                                 if ( !N_NSYM_indexes.empty() )
964                                 {
965                                     symbol_ptr = symtab->SymbolAtIndex(N_NSYM_indexes.back());
966                                     symbol_ptr->SetByteSize(sym_idx + 1);
967                                     symbol_ptr->SetSizeIsSibling(true);
968                                     N_NSYM_indexes.pop_back();
969                                 }
970                                 type = eSymbolTypeScopeEnd;
971                             }
972                             break;
973 
974 
975                         case StabSourceFileOptions:
976                             // N_OPT - emitted with gcc2_compiled and in gcc source
977                             type = eSymbolTypeCompiler;
978                             break;
979 
980                         case StabRegisterSymbol:
981                             // N_RSYM - register sym: name,,NO_SECT,type,register
982                             type = eSymbolTypeVariable;
983                             break;
984 
985                         case StabSourceLine:
986                             // N_SLINE - src line: 0,,n_sect,linenumber,address
987                             symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
988                             type = eSymbolTypeLineEntry;
989                             break;
990 
991                         case StabStructureType:
992                             // N_SSYM - structure elt: name,,NO_SECT,type,struct_offset
993                             type = eSymbolTypeVariableType;
994                             break;
995 
996                         case StabSourceFileName:
997                             // N_SO - source file name
998                             type = eSymbolTypeSourceFile;
999                             if (symbol_name == NULL)
1000                             {
1001                                 if (minimize)
1002                                     add_nlist = false;
1003                                 if (N_SO_index != UINT32_MAX)
1004                                 {
1005                                     // Set the size of the N_SO to the terminating index of this N_SO
1006                                     // so that we can always skip the entire N_SO if we need to navigate
1007                                     // more quickly at the source level when parsing STABS
1008                                     symbol_ptr = symtab->SymbolAtIndex(N_SO_index);
1009                                     symbol_ptr->SetByteSize(sym_idx + (minimize ? 0 : 1));
1010                                     symbol_ptr->SetSizeIsSibling(true);
1011                                 }
1012                                 N_NSYM_indexes.clear();
1013                                 N_INCL_indexes.clear();
1014                                 N_BRAC_indexes.clear();
1015                                 N_COMM_indexes.clear();
1016                                 N_FUN_indexes.clear();
1017                                 N_SO_index = UINT32_MAX;
1018                             }
1019                             else
1020                             {
1021                                 // We use the current number of symbols in the symbol table in lieu of
1022                                 // using nlist_idx in case we ever start trimming entries out
1023                                 if (symbol_name[0] == '/')
1024                                     N_SO_index = sym_idx;
1025                                 else if (minimize && (N_SO_index == sym_idx - 1) && ((sym_idx - 1) < num_syms))
1026                                 {
1027                                     const char *so_path = sym[sym_idx - 1].GetMangled().GetDemangledName().AsCString();
1028                                     if (so_path && so_path[0])
1029                                     {
1030                                         std::string full_so_path (so_path);
1031                                         if (*full_so_path.rbegin() != '/')
1032                                             full_so_path += '/';
1033                                         full_so_path += symbol_name;
1034                                         sym[sym_idx - 1].GetMangled().SetValue(full_so_path.c_str(), false);
1035                                         add_nlist = false;
1036                                         m_nlist_idx_to_sym_idx[nlist_idx] = sym_idx - 1;
1037                                     }
1038                                 }
1039                             }
1040 
1041                             break;
1042 
1043                         case StabObjectFileName:
1044                             // N_OSO - object file name: name,,0,0,st_mtime
1045                             type = eSymbolTypeObjectFile;
1046                             break;
1047 
1048                         case StabLocalSymbol:
1049                             // N_LSYM - local sym: name,,NO_SECT,type,offset
1050                             type = eSymbolTypeLocal;
1051                             break;
1052 
1053                         //----------------------------------------------------------------------
1054                         // INCL scopes
1055                         //----------------------------------------------------------------------
1056                         case StabBeginIncludeFileName:
1057                             // N_BINCL - include file beginning: name,,NO_SECT,0,sum
1058                             // We use the current number of symbols in the symbol table in lieu of
1059                             // using nlist_idx in case we ever start trimming entries out
1060                             N_INCL_indexes.push_back(sym_idx);
1061                             type = eSymbolTypeScopeBegin;
1062                             break;
1063 
1064                         case StabEndIncludeFile:
1065                             // N_EINCL - include file end: name,,NO_SECT,0,0
1066                             // Set the size of the N_BINCL to the terminating index of this N_EINCL
1067                             // so that we can always skip the entire symbol if we need to navigate
1068                             // more quickly at the source level when parsing STABS
1069                             if ( !N_INCL_indexes.empty() )
1070                             {
1071                                 symbol_ptr = symtab->SymbolAtIndex(N_INCL_indexes.back());
1072                                 symbol_ptr->SetByteSize(sym_idx + 1);
1073                                 symbol_ptr->SetSizeIsSibling(true);
1074                                 N_INCL_indexes.pop_back();
1075                             }
1076                             type = eSymbolTypeScopeEnd;
1077                             break;
1078 
1079                         case StabIncludeFileName:
1080                             // N_SOL - #included file name: name,,n_sect,0,address
1081                             type = eSymbolTypeHeaderFile;
1082 
1083                             // We currently don't use the header files on darwin
1084                             if (minimize)
1085                                 add_nlist = false;
1086                             break;
1087 
1088                         case StabCompilerParameters:
1089                             // N_PARAMS - compiler parameters: name,,NO_SECT,0,0
1090                             type = eSymbolTypeCompiler;
1091                             break;
1092 
1093                         case StabCompilerVersion:
1094                             // N_VERSION - compiler version: name,,NO_SECT,0,0
1095                             type = eSymbolTypeCompiler;
1096                             break;
1097 
1098                         case StabCompilerOptLevel:
1099                             // N_OLEVEL - compiler -O level: name,,NO_SECT,0,0
1100                             type = eSymbolTypeCompiler;
1101                             break;
1102 
1103                         case StabParameter:
1104                             // N_PSYM - parameter: name,,NO_SECT,type,offset
1105                             type = eSymbolTypeVariable;
1106                             break;
1107 
1108                         case StabAlternateEntry:
1109                             // N_ENTRY - alternate entry: name,,n_sect,linenumber,address
1110                             symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
1111                             type = eSymbolTypeLineEntry;
1112                             break;
1113 
1114                         //----------------------------------------------------------------------
1115                         // Left and Right Braces
1116                         //----------------------------------------------------------------------
1117                         case StabLeftBracket:
1118                             // N_LBRAC - left bracket: 0,,NO_SECT,nesting level,address
1119                             // We use the current number of symbols in the symbol table in lieu of
1120                             // using nlist_idx in case we ever start trimming entries out
1121                             symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
1122                             N_BRAC_indexes.push_back(sym_idx);
1123                             type = eSymbolTypeScopeBegin;
1124                             break;
1125 
1126                         case StabRightBracket:
1127                             // N_RBRAC - right bracket: 0,,NO_SECT,nesting level,address
1128                             // Set the size of the N_LBRAC to the terminating index of this N_RBRAC
1129                             // so that we can always skip the entire symbol if we need to navigate
1130                             // more quickly at the source level when parsing STABS
1131                             symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
1132                             if ( !N_BRAC_indexes.empty() )
1133                             {
1134                                 symbol_ptr = symtab->SymbolAtIndex(N_BRAC_indexes.back());
1135                                 symbol_ptr->SetByteSize(sym_idx + 1);
1136                                 symbol_ptr->SetSizeIsSibling(true);
1137                                 N_BRAC_indexes.pop_back();
1138                             }
1139                             type = eSymbolTypeScopeEnd;
1140                             break;
1141 
1142                         case StabDeletedIncludeFile:
1143                             // N_EXCL - deleted include file: name,,NO_SECT,0,sum
1144                             type = eSymbolTypeHeaderFile;
1145                             break;
1146 
1147                         //----------------------------------------------------------------------
1148                         // COMM scopes
1149                         //----------------------------------------------------------------------
1150                         case StabBeginCommon:
1151                             // N_BCOMM - begin common: name,,NO_SECT,0,0
1152                             // We use the current number of symbols in the symbol table in lieu of
1153                             // using nlist_idx in case we ever start trimming entries out
1154                             type = eSymbolTypeScopeBegin;
1155                             N_COMM_indexes.push_back(sym_idx);
1156                             break;
1157 
1158                         case StabEndCommonLocal:
1159                             // N_ECOML - end common (local name): 0,,n_sect,0,address
1160                             symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
1161                             // Fall through
1162 
1163                         case StabEndCommon:
1164                             // N_ECOMM - end common: name,,n_sect,0,0
1165                             // Set the size of the N_BCOMM to the terminating index of this N_ECOMM/N_ECOML
1166                             // so that we can always skip the entire symbol if we need to navigate
1167                             // more quickly at the source level when parsing STABS
1168                             if ( !N_COMM_indexes.empty() )
1169                             {
1170                                 symbol_ptr = symtab->SymbolAtIndex(N_COMM_indexes.back());
1171                                 symbol_ptr->SetByteSize(sym_idx + 1);
1172                                 symbol_ptr->SetSizeIsSibling(true);
1173                                 N_COMM_indexes.pop_back();
1174                             }
1175                             type = eSymbolTypeScopeEnd;
1176                             break;
1177 
1178                         case StabLength:
1179                             // N_LENG - second stab entry with length information
1180                             type = eSymbolTypeAdditional;
1181                             break;
1182 
1183                         default: break;
1184                         }
1185                     }
1186                     else
1187                     {
1188                         //uint8_t n_pext    = NlistMaskPrivateExternal & nlist.n_type;
1189                         uint8_t n_type  = NlistMaskType & nlist.n_type;
1190                         sym[sym_idx].SetExternal((NlistMaskExternal & nlist.n_type) != 0);
1191 
1192                         switch (n_type)
1193                         {
1194                         case NListTypeIndirect:         // N_INDR - Fall through
1195                         case NListTypePreboundUndefined:// N_PBUD - Fall through
1196                         case NListTypeUndefined:        // N_UNDF
1197                             type = eSymbolTypeUndefined;
1198                             break;
1199 
1200                         case NListTypeAbsolute:         // N_ABS
1201                             type = eSymbolTypeAbsolute;
1202                             break;
1203 
1204                         case NListTypeSection:          // N_SECT
1205                             symbol_section = section_info.GetSection (nlist.n_sect, nlist.n_value);
1206 
1207                             if (symbol_section == NULL)
1208                             {
1209                                 // TODO: warn about this?
1210                                 add_nlist = false;
1211                                 break;
1212                             }
1213 
1214                             if (TEXT_eh_frame_sectID == nlist.n_sect)
1215                             {
1216                                 type = eSymbolTypeException;
1217                             }
1218                             else
1219                             {
1220                                 uint32_t section_type = symbol_section->Get() & SectionFlagMaskSectionType;
1221 
1222                                 switch (section_type)
1223                                 {
1224                                 case SectionTypeRegular:                     break; // regular section
1225                                 //case SectionTypeZeroFill:                 type = eSymbolTypeData;    break; // zero fill on demand section
1226                                 case SectionTypeCStringLiterals:            type = eSymbolTypeData;    break; // section with only literal C strings
1227                                 case SectionType4ByteLiterals:              type = eSymbolTypeData;    break; // section with only 4 byte literals
1228                                 case SectionType8ByteLiterals:              type = eSymbolTypeData;    break; // section with only 8 byte literals
1229                                 case SectionTypeLiteralPointers:            type = eSymbolTypeTrampoline; break; // section with only pointers to literals
1230                                 case SectionTypeNonLazySymbolPointers:      type = eSymbolTypeTrampoline; break; // section with only non-lazy symbol pointers
1231                                 case SectionTypeLazySymbolPointers:         type = eSymbolTypeTrampoline; break; // section with only lazy symbol pointers
1232                                 case SectionTypeSymbolStubs:                type = eSymbolTypeTrampoline; break; // section with only symbol stubs, byte size of stub in the reserved2 field
1233                                 case SectionTypeModuleInitFunctionPointers: type = eSymbolTypeCode;    break; // section with only function pointers for initialization
1234                                 case SectionTypeModuleTermFunctionPointers: type = eSymbolTypeCode;    break; // section with only function pointers for termination
1235                                 //case SectionTypeCoalesced:                type = eSymbolType;    break; // section contains symbols that are to be coalesced
1236                                 //case SectionTypeZeroFillLarge:            type = eSymbolTypeData;    break; // zero fill on demand section (that can be larger than 4 gigabytes)
1237                                 case SectionTypeInterposing:                type = eSymbolTypeTrampoline;  break; // section with only pairs of function pointers for interposing
1238                                 case SectionType16ByteLiterals:             type = eSymbolTypeData;    break; // section with only 16 byte literals
1239                                 case SectionTypeDTraceObjectFormat:         type = eSymbolTypeInstrumentation; break;
1240                                 case SectionTypeLazyDylibSymbolPointers:    type = eSymbolTypeTrampoline; break;
1241                                 default: break;
1242                                 }
1243 
1244                                 if (type == eSymbolTypeInvalid)
1245                                 {
1246                                     const char *symbol_sect_name = symbol_section->GetName().AsCString();
1247                                     if (symbol_section->IsDescendant (text_section_sp.get()))
1248                                     {
1249                                         if (symbol_section->IsClear(SectionAttrUserPureInstructions |
1250                                                                     SectionAttrUserSelfModifyingCode |
1251                                                                     SectionAttrSytemSomeInstructions))
1252                                             type = eSymbolTypeData;
1253                                         else
1254                                             type = eSymbolTypeCode;
1255                                     }
1256                                     else
1257                                     if (symbol_section->IsDescendant(data_section_sp.get()))
1258                                     {
1259                                         if (symbol_sect_name && ::strstr (symbol_sect_name, "__objc") == symbol_sect_name)
1260                                         {
1261                                             type = eSymbolTypeRuntime;
1262 
1263                                             if (symbol_name &&
1264                                                 symbol_name[0] == '_' &&
1265                                                 symbol_name[1] == 'O' &&
1266                                                 symbol_name[2] == 'B')
1267                                             {
1268                                                 llvm::StringRef symbol_name_ref(symbol_name);
1269                                                 static const llvm::StringRef g_objc_v2_prefix_class ("_OBJC_CLASS_$_");
1270                                                 static const llvm::StringRef g_objc_v2_prefix_metaclass ("_OBJC_METACLASS_$_");
1271                                                 static const llvm::StringRef g_objc_v2_prefix_ivar ("_OBJC_IVAR_$_");
1272                                                 if (symbol_name_ref.startswith(g_objc_v2_prefix_class))
1273                                                 {
1274                                                     symbol_name_non_abi_mangled = symbol_name + 1;
1275                                                     symbol_name = symbol_name + g_objc_v2_prefix_class.size();
1276                                                     type = eSymbolTypeObjCClass;
1277                                                 }
1278                                                 else if (symbol_name_ref.startswith(g_objc_v2_prefix_metaclass))
1279                                                 {
1280                                                     symbol_name_non_abi_mangled = symbol_name + 1;
1281                                                     symbol_name = symbol_name + g_objc_v2_prefix_metaclass.size();
1282                                                     type = eSymbolTypeObjCMetaClass;
1283                                                 }
1284                                                 else if (symbol_name_ref.startswith(g_objc_v2_prefix_ivar))
1285                                                 {
1286                                                     symbol_name_non_abi_mangled = symbol_name + 1;
1287                                                     symbol_name = symbol_name + g_objc_v2_prefix_ivar.size();
1288                                                     type = eSymbolTypeObjCIVar;
1289                                                 }
1290                                             }
1291                                         }
1292                                         else
1293                                         if (symbol_sect_name && ::strstr (symbol_sect_name, "__gcc_except_tab") == symbol_sect_name)
1294                                         {
1295                                             type = eSymbolTypeException;
1296                                         }
1297                                         else
1298                                         {
1299                                             type = eSymbolTypeData;
1300                                         }
1301                                     }
1302                                     else
1303                                     if (symbol_sect_name && ::strstr (symbol_sect_name, "__IMPORT") == symbol_sect_name)
1304                                     {
1305                                         type = eSymbolTypeTrampoline;
1306                                     }
1307                                     else
1308                                     if (symbol_section->IsDescendant(objc_section_sp.get()))
1309                                     {
1310                                         type = eSymbolTypeRuntime;
1311                                         if (symbol_name && symbol_name[0] == '.')
1312                                         {
1313                                             llvm::StringRef symbol_name_ref(symbol_name);
1314                                             static const llvm::StringRef g_objc_v1_prefix_class (".objc_class_name_");
1315                                             if (symbol_name_ref.startswith(g_objc_v1_prefix_class))
1316                                             {
1317                                                 symbol_name_non_abi_mangled = symbol_name;
1318                                                 symbol_name = symbol_name + g_objc_v1_prefix_class.size();
1319                                                 type = eSymbolTypeObjCClass;
1320                                             }
1321                                         }
1322                                     }
1323                                 }
1324                             }
1325                             break;
1326                         }
1327                     }
1328 
1329                     if (add_nlist)
1330                     {
1331                         uint64_t symbol_value = nlist.n_value;
1332                         bool symbol_name_is_mangled = false;
1333 
1334                         if (symbol_name_non_abi_mangled)
1335                         {
1336                             sym[sym_idx].GetMangled().SetMangledName (symbol_name_non_abi_mangled);
1337                             sym[sym_idx].GetMangled().SetDemangledName (symbol_name);
1338                         }
1339                         else
1340                         {
1341                             if (symbol_name && symbol_name[0] == '_')
1342                             {
1343                                 symbol_name_is_mangled = symbol_name[1] == '_';
1344                                 symbol_name++;  // Skip the leading underscore
1345                             }
1346 
1347                             if (symbol_name)
1348                             {
1349                                 sym[sym_idx].GetMangled().SetValue(symbol_name, symbol_name_is_mangled);
1350                             }
1351                         }
1352 
1353                         if (is_debug == false)
1354                         {
1355                             if (type == eSymbolTypeCode)
1356                             {
1357                                 // See if we can find a N_FUN entry for any code symbols.
1358                                 // If we do find a match, and the name matches, then we
1359                                 // can merge the two into just the function symbol to avoid
1360                                 // duplicate entries in the symbol table
1361                                 ValueToSymbolIndexMap::const_iterator pos = N_FUN_addr_to_sym_idx.find (nlist.n_value);
1362                                 if (pos != N_FUN_addr_to_sym_idx.end())
1363                                 {
1364                                     if ((symbol_name_is_mangled == true && sym[sym_idx].GetMangled().GetMangledName() == sym[pos->second].GetMangled().GetMangledName()) ||
1365                                         (symbol_name_is_mangled == false && sym[sym_idx].GetMangled().GetDemangledName() == sym[pos->second].GetMangled().GetDemangledName()))
1366                                     {
1367                                         m_nlist_idx_to_sym_idx[nlist_idx] = pos->second;
1368                                         // We just need the flags from the linker symbol, so put these flags
1369                                         // into the N_FUN flags to avoid duplicate symbols in the symbol table
1370                                         sym[pos->second].SetFlags (nlist.n_type << 16 | nlist.n_desc);
1371                                         sym[sym_idx].Clear();
1372                                         continue;
1373                                     }
1374                                 }
1375                             }
1376                             else if (type == eSymbolTypeData)
1377                             {
1378                                 // See if we can find a N_STSYM entry for any data symbols.
1379                                 // If we do find a match, and the name matches, then we
1380                                 // can merge the two into just the Static symbol to avoid
1381                                 // duplicate entries in the symbol table
1382                                 ValueToSymbolIndexMap::const_iterator pos = N_STSYM_addr_to_sym_idx.find (nlist.n_value);
1383                                 if (pos != N_STSYM_addr_to_sym_idx.end())
1384                                 {
1385                                     if ((symbol_name_is_mangled == true && sym[sym_idx].GetMangled().GetMangledName() == sym[pos->second].GetMangled().GetMangledName()) ||
1386                                         (symbol_name_is_mangled == false && sym[sym_idx].GetMangled().GetDemangledName() == sym[pos->second].GetMangled().GetDemangledName()))
1387                                     {
1388                                         m_nlist_idx_to_sym_idx[nlist_idx] = pos->second;
1389                                         // We just need the flags from the linker symbol, so put these flags
1390                                         // into the N_STSYM flags to avoid duplicate symbols in the symbol table
1391                                         sym[pos->second].SetFlags (nlist.n_type << 16 | nlist.n_desc);
1392                                         sym[sym_idx].Clear();
1393                                         continue;
1394                                     }
1395                                 }
1396                             }
1397                         }
1398                         if (symbol_section != NULL)
1399                             symbol_value -= symbol_section->GetFileAddress();
1400 
1401                         sym[sym_idx].SetID (nlist_idx);
1402                         sym[sym_idx].SetType (type);
1403                         sym[sym_idx].GetAddressRangeRef().GetBaseAddress().SetSection (symbol_section);
1404                         sym[sym_idx].GetAddressRangeRef().GetBaseAddress().SetOffset (symbol_value);
1405                         sym[sym_idx].SetFlags (nlist.n_type << 16 | nlist.n_desc);
1406 
1407                         ++sym_idx;
1408                     }
1409                     else
1410                     {
1411                         sym[sym_idx].Clear();
1412                     }
1413 
1414                 }
1415 
1416                 // STAB N_GSYM entries end up having a symbol type eSymbolTypeGlobal and when the symbol value
1417                 // is zero, the address of the global ends up being in a non-STAB entry. Try and fix up all
1418                 // such entries by figuring out what the address for the global is by looking up this non-STAB
1419                 // entry and copying the value into the debug symbol's value to save us the hassle in the
1420                 // debug symbol parser.
1421 
1422                 Symbol *global_symbol = NULL;
1423                 for (nlist_idx = 0;
1424                      nlist_idx < symtab_load_command.nsyms && (global_symbol = symtab->FindSymbolWithType (eSymbolTypeData, Symtab::eDebugYes, Symtab::eVisibilityAny, nlist_idx)) != NULL;
1425                      nlist_idx++)
1426                 {
1427                     if (global_symbol->GetValue().GetFileAddress() == 0)
1428                     {
1429                         std::vector<uint32_t> indexes;
1430                         if (symtab->AppendSymbolIndexesWithName (global_symbol->GetMangled().GetName(), indexes) > 0)
1431                         {
1432                             std::vector<uint32_t>::const_iterator pos;
1433                             std::vector<uint32_t>::const_iterator end = indexes.end();
1434                             for (pos = indexes.begin(); pos != end; ++pos)
1435                             {
1436                                 symbol_ptr = symtab->SymbolAtIndex(*pos);
1437                                 if (symbol_ptr != global_symbol && symbol_ptr->IsDebug() == false)
1438                                 {
1439                                     global_symbol->SetValue(symbol_ptr->GetValue());
1440                                     break;
1441                                 }
1442                             }
1443                         }
1444                     }
1445                 }
1446 
1447                 // Trim our symbols down to just what we ended up with after
1448                 // removing any symbols.
1449                 if (sym_idx < num_syms)
1450                 {
1451                     num_syms = sym_idx;
1452                     sym = symtab->Resize (num_syms);
1453                 }
1454 
1455                 // Now synthesize indirect symbols
1456                 if (m_dysymtab.nindirectsyms != 0)
1457                 {
1458                     DataBufferSP indirect_symbol_indexes_sp(m_file.ReadFileContents(m_offset + m_dysymtab.indirectsymoff, m_dysymtab.nindirectsyms * 4));
1459 
1460                     if (indirect_symbol_indexes_sp && indirect_symbol_indexes_sp->GetByteSize())
1461                     {
1462                         NListIndexToSymbolIndexMap::const_iterator end_index_pos = m_nlist_idx_to_sym_idx.end();
1463                         DataExtractor indirect_symbol_index_data (indirect_symbol_indexes_sp, m_data.GetByteOrder(), m_data.GetAddressByteSize());
1464 
1465                         for (uint32_t sect_idx = 1; sect_idx < m_mach_sections.size(); ++sect_idx)
1466                         {
1467                             if ((m_mach_sections[sect_idx].flags & SectionFlagMaskSectionType) == SectionTypeSymbolStubs)
1468                             {
1469                                 uint32_t symbol_stub_byte_size = m_mach_sections[sect_idx].reserved2;
1470                                 if (symbol_stub_byte_size == 0)
1471                                     continue;
1472 
1473                                 const uint32_t num_symbol_stubs = m_mach_sections[sect_idx].size / symbol_stub_byte_size;
1474 
1475                                 if (num_symbol_stubs == 0)
1476                                     continue;
1477 
1478                                 const uint32_t symbol_stub_index_offset = m_mach_sections[sect_idx].reserved1;
1479                                 uint32_t synthetic_stub_sym_id = symtab_load_command.nsyms;
1480                                 for (uint32_t stub_idx = 0; stub_idx < num_symbol_stubs; ++stub_idx)
1481                                 {
1482                                     const uint32_t symbol_stub_index = symbol_stub_index_offset + stub_idx;
1483                                     const lldb::addr_t symbol_stub_addr = m_mach_sections[sect_idx].addr + (stub_idx * symbol_stub_byte_size);
1484                                     uint32_t symbol_stub_offset = symbol_stub_index * 4;
1485                                     if (indirect_symbol_index_data.ValidOffsetForDataOfSize(symbol_stub_offset, 4))
1486                                     {
1487                                         const uint32_t stub_sym_id = indirect_symbol_index_data.GetU32 (&symbol_stub_offset);
1488                                         if (stub_sym_id & (IndirectSymbolAbsolute | IndirectSymbolLocal))
1489                                             continue;
1490 
1491                                         NListIndexToSymbolIndexMap::const_iterator index_pos = m_nlist_idx_to_sym_idx.find (stub_sym_id);
1492                                         Symbol *stub_symbol = NULL;
1493                                         if (index_pos != end_index_pos)
1494                                         {
1495                                             // We have a remapping from the original nlist index to
1496                                             // a current symbol index, so just look this up by index
1497                                             stub_symbol = symtab->SymbolAtIndex (index_pos->second);
1498                                         }
1499                                         else
1500                                         {
1501                                             // We need to lookup a symbol using the original nlist
1502                                             // symbol index since this index is coming from the
1503                                             // S_SYMBOL_STUBS
1504                                             stub_symbol = symtab->FindSymbolByID (stub_sym_id);
1505                                         }
1506 
1507                                         assert (stub_symbol);
1508                                         if (stub_symbol)
1509                                         {
1510                                             Address so_addr(symbol_stub_addr, section_list);
1511 
1512                                             if (stub_symbol->GetType() == eSymbolTypeUndefined)
1513                                             {
1514                                                 // Change the external symbol into a trampoline that makes sense
1515                                                 // These symbols were N_UNDF N_EXT, and are useless to us, so we
1516                                                 // can re-use them so we don't have to make up a synthetic symbol
1517                                                 // for no good reason.
1518                                                 stub_symbol->SetType (eSymbolTypeTrampoline);
1519                                                 stub_symbol->SetExternal (false);
1520                                                 stub_symbol->GetAddressRangeRef().GetBaseAddress() = so_addr;
1521                                                 stub_symbol->GetAddressRangeRef().SetByteSize (symbol_stub_byte_size);
1522                                             }
1523                                             else
1524                                             {
1525                                                 // Make a synthetic symbol to describe the trampoline stub
1526                                                 if (sym_idx >= num_syms)
1527                                                     sym = symtab->Resize (++num_syms);
1528                                                 sym[sym_idx].SetID (synthetic_stub_sym_id++);
1529                                                 sym[sym_idx].GetMangled() = stub_symbol->GetMangled();
1530                                                 sym[sym_idx].SetType (eSymbolTypeTrampoline);
1531                                                 sym[sym_idx].SetIsSynthetic (true);
1532                                                 sym[sym_idx].GetAddressRangeRef().GetBaseAddress() = so_addr;
1533                                                 sym[sym_idx].GetAddressRangeRef().SetByteSize (symbol_stub_byte_size);
1534                                                 ++sym_idx;
1535                                             }
1536                                         }
1537                                     }
1538                                 }
1539                             }
1540                         }
1541                     }
1542                 }
1543 
1544 
1545 
1546                 return symtab->GetNumSymbols();
1547             }
1548         }
1549         offset = cmd_offset + symtab_load_command.cmdsize;
1550     }
1551     return 0;
1552 }
1553 
1554 
1555 void
1556 ObjectFileMachO::Dump (Stream *s)
1557 {
1558     lldb_private::Mutex::Locker locker(m_mutex);
1559     s->Printf("%p: ", this);
1560     s->Indent();
1561     if (m_header.magic == HeaderMagic64 || m_header.magic == HeaderMagic64Swapped)
1562         s->PutCString("ObjectFileMachO64");
1563     else
1564         s->PutCString("ObjectFileMachO32");
1565 
1566     ArchSpec header_arch(eArchTypeMachO, m_header.cputype, m_header.cpusubtype);
1567 
1568     *s << ", file = '" << m_file << "', arch = " << header_arch.GetArchitectureName() << "\n";
1569 
1570     if (m_sections_ap.get())
1571         m_sections_ap->Dump(s, NULL, true, UINT32_MAX);
1572 
1573     if (m_symtab_ap.get())
1574         m_symtab_ap->Dump(s, NULL, eSortOrderNone);
1575 }
1576 
1577 
1578 bool
1579 ObjectFileMachO::GetUUID (lldb_private::UUID* uuid)
1580 {
1581     lldb_private::Mutex::Locker locker(m_mutex);
1582     struct uuid_command load_cmd;
1583     uint32_t offset = MachHeaderSizeFromMagic(m_header.magic);
1584     uint32_t i;
1585     for (i=0; i<m_header.ncmds; ++i)
1586     {
1587         const uint32_t cmd_offset = offset;
1588         if (m_data.GetU32(&offset, &load_cmd, 2) == NULL)
1589             break;
1590 
1591         if (load_cmd.cmd == LoadCommandUUID)
1592         {
1593             const uint8_t *uuid_bytes = m_data.PeekData(offset, 16);
1594             if (uuid_bytes)
1595             {
1596                 uuid->SetBytes (uuid_bytes);
1597                 return true;
1598             }
1599             return false;
1600         }
1601         offset = cmd_offset + load_cmd.cmdsize;
1602     }
1603     return false;
1604 }
1605 
1606 
1607 uint32_t
1608 ObjectFileMachO::GetDependentModules (FileSpecList& files)
1609 {
1610     lldb_private::Mutex::Locker locker(m_mutex);
1611     struct load_command load_cmd;
1612     uint32_t offset = MachHeaderSizeFromMagic(m_header.magic);
1613     uint32_t count = 0;
1614     const bool resolve_path = false; // Don't resolve the dependend file paths since they may not reside on this system
1615     uint32_t i;
1616     for (i=0; i<m_header.ncmds; ++i)
1617     {
1618         const uint32_t cmd_offset = offset;
1619         if (m_data.GetU32(&offset, &load_cmd, 2) == NULL)
1620             break;
1621 
1622         switch (load_cmd.cmd)
1623         {
1624         case LoadCommandDylibLoad:
1625         case LoadCommandDylibLoadWeak:
1626         case LoadCommandDylibReexport:
1627         case LoadCommandDynamicLinkerLoad:
1628         case LoadCommandFixedVMShlibLoad:
1629         case LoadCommandDylibLoadUpward:
1630             {
1631                 uint32_t name_offset = cmd_offset + m_data.GetU32(&offset);
1632                 const char *path = m_data.PeekCStr(name_offset);
1633                 // Skip any path that starts with '@' since these are usually:
1634                 // @executable_path/.../file
1635                 // @rpath/.../file
1636                 if (path && path[0] != '@')
1637                 {
1638                     FileSpec file_spec(path, resolve_path);
1639                     if (files.AppendIfUnique(file_spec))
1640                         count++;
1641                 }
1642             }
1643             break;
1644 
1645         default:
1646             break;
1647         }
1648         offset = cmd_offset + load_cmd.cmdsize;
1649     }
1650     return count;
1651 }
1652 
1653 lldb_private::Address
1654 ObjectFileMachO::GetEntryPointAddress ()
1655 {
1656     // If the object file is not an executable it can't hold the entry point.  m_entry_point_address
1657     // is initialized to an invalid address, so we can just return that.
1658     // If m_entry_point_address is valid it means we've found it already, so return the cached value.
1659 
1660     if (!IsExecutable() || m_entry_point_address.IsValid())
1661         return m_entry_point_address;
1662 
1663     // Otherwise, look for the UnixThread or Thread command.  The data for the Thread command is given in
1664     // /usr/include/mach-o.h, but it is basically:
1665     //
1666     //  uint32_t flavor  - this is the flavor argument you would pass to thread_get_state
1667     //  uint32_t count   - this is the count of longs in the thread state data
1668     //  struct XXX_thread_state state - this is the structure from <machine/thread_status.h> corresponding to the flavor.
1669     //  <repeat this trio>
1670     //
1671     // So we just keep reading the various register flavors till we find the GPR one, then read the PC out of there.
1672     // FIXME: We will need to have a "RegisterContext data provider" class at some point that can get all the registers
1673     // out of data in this form & attach them to a given thread.  That should underlie the MacOS X User process plugin,
1674     // and we'll also need it for the MacOS X Core File process plugin.  When we have that we can also use it here.
1675     //
1676     // For now we hard-code the offsets and flavors we need:
1677     //
1678     //
1679 
1680     lldb_private::Mutex::Locker locker(m_mutex);
1681     struct load_command load_cmd;
1682     uint32_t offset = MachHeaderSizeFromMagic(m_header.magic);
1683     uint32_t i;
1684     lldb::addr_t start_address = LLDB_INVALID_ADDRESS;
1685     bool done = false;
1686 
1687     for (i=0; i<m_header.ncmds; ++i)
1688     {
1689         const uint32_t cmd_offset = offset;
1690         if (m_data.GetU32(&offset, &load_cmd, 2) == NULL)
1691             break;
1692 
1693         switch (load_cmd.cmd)
1694         {
1695         case LoadCommandUnixThread:
1696         case LoadCommandThread:
1697             {
1698                 while (offset < cmd_offset + load_cmd.cmdsize)
1699                 {
1700                     uint32_t flavor = m_data.GetU32(&offset);
1701                     uint32_t count = m_data.GetU32(&offset);
1702                     if (count == 0)
1703                     {
1704                         // We've gotten off somehow, log and exit;
1705                         return m_entry_point_address;
1706                     }
1707 
1708                     switch (m_header.cputype)
1709                     {
1710                     case llvm::MachO::CPUTypeARM:
1711                        if (flavor == 1) // ARM_THREAD_STATE from mach/arm/thread_status.h
1712                        {
1713                            offset += 60;  // This is the offset of pc in the GPR thread state data structure.
1714                            start_address = m_data.GetU32(&offset);
1715                            done = true;
1716                         }
1717                     break;
1718                     case llvm::MachO::CPUTypeI386:
1719                        if (flavor == 1) // x86_THREAD_STATE32 from mach/i386/thread_status.h
1720                        {
1721                            offset += 40;  // This is the offset of eip in the GPR thread state data structure.
1722                            start_address = m_data.GetU32(&offset);
1723                            done = true;
1724                         }
1725                     break;
1726                     case llvm::MachO::CPUTypeX86_64:
1727                        if (flavor == 4) // x86_THREAD_STATE64 from mach/i386/thread_status.h
1728                        {
1729                            offset += 16 * 8;  // This is the offset of rip in the GPR thread state data structure.
1730                            start_address = m_data.GetU64(&offset);
1731                            done = true;
1732                         }
1733                     break;
1734                     default:
1735                         return m_entry_point_address;
1736                     }
1737                     // Haven't found the GPR flavor yet, skip over the data for this flavor:
1738                     if (done)
1739                         break;
1740                     offset += count * 4;
1741                 }
1742             }
1743             break;
1744 
1745         default:
1746             break;
1747         }
1748         if (done)
1749             break;
1750 
1751         // Go to the next load command:
1752         offset = cmd_offset + load_cmd.cmdsize;
1753     }
1754 
1755     if (start_address != LLDB_INVALID_ADDRESS)
1756     {
1757         // We got the start address from the load commands, so now resolve that address in the sections
1758         // of this ObjectFile:
1759         if (!m_entry_point_address.ResolveAddressUsingFileSections (start_address, GetSectionList()))
1760         {
1761             m_entry_point_address.Clear();
1762         }
1763     }
1764     else
1765     {
1766         // We couldn't read the UnixThread load command - maybe it wasn't there.  As a fallback look for the
1767         // "start" symbol in the main executable.
1768 
1769         SymbolContextList contexts;
1770         SymbolContext context;
1771         if (!m_module->FindSymbolsWithNameAndType(ConstString ("start"), eSymbolTypeCode, contexts))
1772             return m_entry_point_address;
1773 
1774         contexts.GetContextAtIndex(0, context);
1775 
1776         m_entry_point_address = context.symbol->GetValue();
1777     }
1778 
1779     return m_entry_point_address;
1780 
1781 }
1782 
1783 ObjectFile::Type
1784 ObjectFileMachO::CalculateType()
1785 {
1786     switch (m_header.filetype)
1787     {
1788         case HeaderFileTypeObject:                                          // 0x1u MH_OBJECT
1789             if (GetAddressByteSize () == 4)
1790             {
1791                 // 32 bit kexts are just object files, but they do have a valid
1792                 // UUID load command.
1793                 UUID uuid;
1794                 if (GetUUID(&uuid))
1795                 {
1796                     // this checking for the UUID load command is not enough
1797                     // we could eventually look for the symbol named
1798                     // "OSKextGetCurrentIdentifier" as this is required of kexts
1799                     if (m_strata == eStrataInvalid)
1800                         m_strata = eStrataKernel;
1801                     return eTypeSharedLibrary;
1802                 }
1803             }
1804             return eTypeObjectFile;
1805 
1806         case HeaderFileTypeExecutable:          return eTypeExecutable;     // 0x2u MH_EXECUTE
1807         case HeaderFileTypeFixedVMShlib:        return eTypeSharedLibrary;  // 0x3u MH_FVMLIB
1808         case HeaderFileTypeCore:                return eTypeCoreFile;       // 0x4u MH_CORE
1809         case HeaderFileTypePreloadedExecutable: return eTypeSharedLibrary;  // 0x5u MH_PRELOAD
1810         case HeaderFileTypeDynamicShlib:        return eTypeSharedLibrary;  // 0x6u MH_DYLIB
1811         case HeaderFileTypeDynamicLinkEditor:   return eTypeDynamicLinker;  // 0x7u MH_DYLINKER
1812         case HeaderFileTypeBundle:              return eTypeSharedLibrary;  // 0x8u MH_BUNDLE
1813         case HeaderFileTypeDynamicShlibStub:    return eTypeStubLibrary;    // 0x9u MH_DYLIB_STUB
1814         case HeaderFileTypeDSYM:                return eTypeDebugInfo;      // 0xAu MH_DSYM
1815         case HeaderFileTypeKextBundle:          return eTypeSharedLibrary;  // 0xBu MH_KEXT_BUNDLE
1816         default:
1817             break;
1818     }
1819     return eTypeUnknown;
1820 }
1821 
1822 ObjectFile::Strata
1823 ObjectFileMachO::CalculateStrata()
1824 {
1825     switch (m_header.filetype)
1826     {
1827         case HeaderFileTypeObject:      // 0x1u MH_OBJECT
1828             {
1829                 // 32 bit kexts are just object files, but they do have a valid
1830                 // UUID load command.
1831                 UUID uuid;
1832                 if (GetUUID(&uuid))
1833                 {
1834                     // this checking for the UUID load command is not enough
1835                     // we could eventually look for the symbol named
1836                     // "OSKextGetCurrentIdentifier" as this is required of kexts
1837                     if (m_type == eTypeInvalid)
1838                         m_type = eTypeSharedLibrary;
1839 
1840                     return eStrataKernel;
1841                 }
1842             }
1843             return eStrataUnknown;
1844 
1845         case HeaderFileTypeExecutable:                                     // 0x2u MH_EXECUTE
1846             // Check for the MH_DYLDLINK bit in the flags
1847             if (m_header.flags & HeaderFlagBitIsDynamicLinkObject)
1848                 return eStrataUser;
1849             return eStrataKernel;
1850 
1851         case HeaderFileTypeFixedVMShlib:        return eStrataUser;         // 0x3u MH_FVMLIB
1852         case HeaderFileTypeCore:                return eStrataUnknown;      // 0x4u MH_CORE
1853         case HeaderFileTypePreloadedExecutable: return eStrataUser;         // 0x5u MH_PRELOAD
1854         case HeaderFileTypeDynamicShlib:        return eStrataUser;         // 0x6u MH_DYLIB
1855         case HeaderFileTypeDynamicLinkEditor:   return eStrataUser;         // 0x7u MH_DYLINKER
1856         case HeaderFileTypeBundle:              return eStrataUser;         // 0x8u MH_BUNDLE
1857         case HeaderFileTypeDynamicShlibStub:    return eStrataUser;         // 0x9u MH_DYLIB_STUB
1858         case HeaderFileTypeDSYM:                return eStrataUnknown;      // 0xAu MH_DSYM
1859         case HeaderFileTypeKextBundle:          return eStrataKernel;       // 0xBu MH_KEXT_BUNDLE
1860         default:
1861             break;
1862     }
1863     return eStrataUnknown;
1864 }
1865 
1866 
1867 bool
1868 ObjectFileMachO::GetArchitecture (ArchSpec &arch)
1869 {
1870     lldb_private::Mutex::Locker locker(m_mutex);
1871     arch.SetArchitecture (eArchTypeMachO, m_header.cputype, m_header.cpusubtype);
1872 
1873     // Files with type MH_PRELOAD are currently used in cases where the image
1874     // debugs at the addresses in the file itself. Below we set the OS to
1875     // unknown to make sure we use the DynamicLoaderStatic()...
1876     if (m_header.filetype == HeaderFileTypePreloadedExecutable)
1877     {
1878         arch.GetTriple().setOS (llvm::Triple::UnknownOS);
1879     }
1880 
1881     return true;
1882 }
1883 
1884 
1885 //------------------------------------------------------------------
1886 // PluginInterface protocol
1887 //------------------------------------------------------------------
1888 const char *
1889 ObjectFileMachO::GetPluginName()
1890 {
1891     return "ObjectFileMachO";
1892 }
1893 
1894 const char *
1895 ObjectFileMachO::GetShortPluginName()
1896 {
1897     return GetPluginNameStatic();
1898 }
1899 
1900 uint32_t
1901 ObjectFileMachO::GetPluginVersion()
1902 {
1903     return 1;
1904 }
1905 
1906