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