xref: /llvm-project/llvm/lib/Object/MachOObjectFile.cpp (revision ee3be4f2a9c4c7e46d9408ef641fbb370de752d9) 
1 //===- MachOObjectFile.cpp - Mach-O object file binding ---------*- 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 // This file defines the MachOObjectFile class, which binds the MachOObject
11 // class to the generic ObjectFile wrapper.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/ADT/Triple.h"
16 #include "llvm/Object/MachOFormat.h"
17 #include "llvm/Object/MachOObject.h"
18 #include "llvm/Object/ObjectFile.h"
19 #include "llvm/Support/MemoryBuffer.h"
20 #include "llvm/Support/MachO.h"
21 #include "llvm/ADT/SmallVector.h"
22 
23 #include <cctype>
24 #include <cstring>
25 #include <limits>
26 
27 using namespace llvm;
28 using namespace object;
29 
30 namespace llvm {
31 
32 typedef MachOObject::LoadCommandInfo LoadCommandInfo;
33 
34 class MachOObjectFile : public ObjectFile {
35 public:
36   MachOObjectFile(MemoryBuffer *Object, MachOObject *MOO, error_code &ec);
37 
38   virtual symbol_iterator begin_symbols() const;
39   virtual symbol_iterator end_symbols() const;
40   virtual section_iterator begin_sections() const;
41   virtual section_iterator end_sections() const;
42 
43   virtual uint8_t getBytesInAddress() const;
44   virtual StringRef getFileFormatName() const;
45   virtual unsigned getArch() const;
46 
47 protected:
48   virtual error_code getSymbolNext(DataRefImpl Symb, SymbolRef &Res) const;
49   virtual error_code getSymbolName(DataRefImpl Symb, StringRef &Res) const;
50   virtual error_code getSymbolOffset(DataRefImpl Symb, uint64_t &Res) const;
51   virtual error_code getSymbolAddress(DataRefImpl Symb, uint64_t &Res) const;
52   virtual error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const;
53   virtual error_code getSymbolNMTypeChar(DataRefImpl Symb, char &Res) const;
54   virtual error_code isSymbolInternal(DataRefImpl Symb, bool &Res) const;
55   virtual error_code isSymbolGlobal(DataRefImpl Symb, bool &Res) const;
56   virtual error_code getSymbolType(DataRefImpl Symb, SymbolRef::SymbolType &Res) const;
57 
58   virtual error_code getSectionNext(DataRefImpl Sec, SectionRef &Res) const;
59   virtual error_code getSectionName(DataRefImpl Sec, StringRef &Res) const;
60   virtual error_code getSectionAddress(DataRefImpl Sec, uint64_t &Res) const;
61   virtual error_code getSectionSize(DataRefImpl Sec, uint64_t &Res) const;
62   virtual error_code getSectionContents(DataRefImpl Sec, StringRef &Res) const;
63   virtual error_code getSectionAlignment(DataRefImpl Sec, uint64_t &Res) const;
64   virtual error_code isSectionText(DataRefImpl Sec, bool &Res) const;
65   virtual error_code isSectionData(DataRefImpl Sec, bool &Res) const;
66   virtual error_code isSectionBSS(DataRefImpl Sec, bool &Res) const;
67   virtual error_code sectionContainsSymbol(DataRefImpl DRI, DataRefImpl S,
68                                            bool &Result) const;
69   virtual relocation_iterator getSectionRelBegin(DataRefImpl Sec) const;
70   virtual relocation_iterator getSectionRelEnd(DataRefImpl Sec) const;
71 
72   virtual error_code getRelocationNext(DataRefImpl Rel,
73                                        RelocationRef &Res) const;
74   virtual error_code getRelocationAddress(DataRefImpl Rel,
75                                           uint64_t &Res) const;
76   virtual error_code getRelocationSymbol(DataRefImpl Rel,
77                                          SymbolRef &Res) const;
78   virtual error_code getRelocationType(DataRefImpl Rel,
79                                        uint32_t &Res) const;
80   virtual error_code getRelocationTypeName(DataRefImpl Rel,
81                                            SmallVectorImpl<char> &Result) const;
82   virtual error_code getRelocationAdditionalInfo(DataRefImpl Rel,
83                                                  int64_t &Res) const;
84   virtual error_code getRelocationValueString(DataRefImpl Rel,
85                                            SmallVectorImpl<char> &Result) const;
86 
87 private:
88   MachOObject *MachOObj;
89   mutable uint32_t RegisteredStringTable;
90   typedef SmallVector<DataRefImpl, 1> SectionList;
91   SectionList Sections;
92 
93 
94   void moveToNextSection(DataRefImpl &DRI) const;
95   void getSymbolTableEntry(DataRefImpl DRI,
96                            InMemoryStruct<macho::SymbolTableEntry> &Res) const;
97   void getSymbol64TableEntry(DataRefImpl DRI,
98                           InMemoryStruct<macho::Symbol64TableEntry> &Res) const;
99   void moveToNextSymbol(DataRefImpl &DRI) const;
100   void getSection(DataRefImpl DRI, InMemoryStruct<macho::Section> &Res) const;
101   void getSection64(DataRefImpl DRI,
102                     InMemoryStruct<macho::Section64> &Res) const;
103   void getRelocation(DataRefImpl Rel,
104                      InMemoryStruct<macho::RelocationEntry> &Res) const;
105   std::size_t getSectionIndex(DataRefImpl Sec) const;
106 };
107 
108 MachOObjectFile::MachOObjectFile(MemoryBuffer *Object, MachOObject *MOO,
109                                  error_code &ec)
110     : ObjectFile(Binary::isMachO, Object, ec),
111       MachOObj(MOO),
112       RegisteredStringTable(std::numeric_limits<uint32_t>::max()) {
113   DataRefImpl DRI;
114   DRI.d.a = DRI.d.b = 0;
115   moveToNextSection(DRI);
116   uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
117   while (DRI.d.a < LoadCommandCount) {
118     Sections.push_back(DRI);
119     DRI.d.b++;
120     moveToNextSection(DRI);
121   }
122 }
123 
124 
125 ObjectFile *ObjectFile::createMachOObjectFile(MemoryBuffer *Buffer) {
126   error_code ec;
127   std::string Err;
128   MachOObject *MachOObj = MachOObject::LoadFromBuffer(Buffer, &Err);
129   if (!MachOObj)
130     return NULL;
131   return new MachOObjectFile(Buffer, MachOObj, ec);
132 }
133 
134 /*===-- Symbols -----------------------------------------------------------===*/
135 
136 void MachOObjectFile::moveToNextSymbol(DataRefImpl &DRI) const {
137   uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
138   while (DRI.d.a < LoadCommandCount) {
139     LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
140     if (LCI.Command.Type == macho::LCT_Symtab) {
141       InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
142       MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
143       if (DRI.d.b < SymtabLoadCmd->NumSymbolTableEntries)
144         return;
145     }
146 
147     DRI.d.a++;
148     DRI.d.b = 0;
149   }
150 }
151 
152 void MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI,
153     InMemoryStruct<macho::SymbolTableEntry> &Res) const {
154   InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
155   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
156   MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
157 
158   if (RegisteredStringTable != DRI.d.a) {
159     MachOObj->RegisterStringTable(*SymtabLoadCmd);
160     RegisteredStringTable = DRI.d.a;
161   }
162 
163   MachOObj->ReadSymbolTableEntry(SymtabLoadCmd->SymbolTableOffset, DRI.d.b,
164                                  Res);
165 }
166 
167 void MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI,
168     InMemoryStruct<macho::Symbol64TableEntry> &Res) const {
169   InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
170   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
171   MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
172 
173   if (RegisteredStringTable != DRI.d.a) {
174     MachOObj->RegisterStringTable(*SymtabLoadCmd);
175     RegisteredStringTable = DRI.d.a;
176   }
177 
178   MachOObj->ReadSymbol64TableEntry(SymtabLoadCmd->SymbolTableOffset, DRI.d.b,
179                                    Res);
180 }
181 
182 
183 error_code MachOObjectFile::getSymbolNext(DataRefImpl DRI,
184                                           SymbolRef &Result) const {
185   DRI.d.b++;
186   moveToNextSymbol(DRI);
187   Result = SymbolRef(DRI, this);
188   return object_error::success;
189 }
190 
191 error_code MachOObjectFile::getSymbolName(DataRefImpl DRI,
192                                           StringRef &Result) const {
193   if (MachOObj->is64Bit()) {
194     InMemoryStruct<macho::Symbol64TableEntry> Entry;
195     getSymbol64TableEntry(DRI, Entry);
196     Result = MachOObj->getStringAtIndex(Entry->StringIndex);
197   } else {
198     InMemoryStruct<macho::SymbolTableEntry> Entry;
199     getSymbolTableEntry(DRI, Entry);
200     Result = MachOObj->getStringAtIndex(Entry->StringIndex);
201   }
202   return object_error::success;
203 }
204 
205 error_code MachOObjectFile::getSymbolOffset(DataRefImpl DRI,
206                                              uint64_t &Result) const {
207   if (MachOObj->is64Bit()) {
208     InMemoryStruct<macho::Symbol64TableEntry> Entry;
209     getSymbol64TableEntry(DRI, Entry);
210     Result = Entry->Value;
211   } else {
212     InMemoryStruct<macho::SymbolTableEntry> Entry;
213     getSymbolTableEntry(DRI, Entry);
214     Result = Entry->Value;
215   }
216   return object_error::success;
217 }
218 
219 error_code MachOObjectFile::getSymbolAddress(DataRefImpl DRI,
220                                              uint64_t &Result) const {
221   uint64_t SymbolOffset;
222   uint8_t SectionIndex;
223   if (MachOObj->is64Bit()) {
224     InMemoryStruct<macho::Symbol64TableEntry> Entry;
225     getSymbol64TableEntry(DRI, Entry);
226     SymbolOffset = Entry->Value;
227     SectionIndex = Entry->SectionIndex;
228   } else {
229     InMemoryStruct<macho::SymbolTableEntry> Entry;
230     getSymbolTableEntry(DRI, Entry);
231     SymbolOffset = Entry->Value;
232     SectionIndex = Entry->SectionIndex;
233   }
234   getSectionAddress(Sections[SectionIndex], Result);
235   Result += SymbolOffset;
236 
237   return object_error::success;
238 }
239 
240 error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
241                                           uint64_t &Result) const {
242   Result = UnknownAddressOrSize;
243   return object_error::success;
244 }
245 
246 error_code MachOObjectFile::getSymbolNMTypeChar(DataRefImpl DRI,
247                                                 char &Result) const {
248   uint8_t Type, Flags;
249   if (MachOObj->is64Bit()) {
250     InMemoryStruct<macho::Symbol64TableEntry> Entry;
251     getSymbol64TableEntry(DRI, Entry);
252     Type = Entry->Type;
253     Flags = Entry->Flags;
254   } else {
255     InMemoryStruct<macho::SymbolTableEntry> Entry;
256     getSymbolTableEntry(DRI, Entry);
257     Type = Entry->Type;
258     Flags = Entry->Flags;
259   }
260 
261   char Char;
262   switch (Type & macho::STF_TypeMask) {
263     case macho::STT_Undefined:
264       Char = 'u';
265       break;
266     case macho::STT_Absolute:
267     case macho::STT_Section:
268       Char = 's';
269       break;
270     default:
271       Char = '?';
272       break;
273   }
274 
275   if (Flags & (macho::STF_External | macho::STF_PrivateExtern))
276     Char = toupper(Char);
277   Result = Char;
278   return object_error::success;
279 }
280 
281 error_code MachOObjectFile::isSymbolInternal(DataRefImpl DRI,
282                                              bool &Result) const {
283   if (MachOObj->is64Bit()) {
284     InMemoryStruct<macho::Symbol64TableEntry> Entry;
285     getSymbol64TableEntry(DRI, Entry);
286     Result = Entry->Flags & macho::STF_StabsEntryMask;
287   } else {
288     InMemoryStruct<macho::SymbolTableEntry> Entry;
289     getSymbolTableEntry(DRI, Entry);
290     Result = Entry->Flags & macho::STF_StabsEntryMask;
291   }
292   return object_error::success;
293 }
294 
295 error_code MachOObjectFile::isSymbolGlobal(DataRefImpl Symb, bool &Res) const {
296 
297   if (MachOObj->is64Bit()) {
298     InMemoryStruct<macho::Symbol64TableEntry> Entry;
299     getSymbol64TableEntry(Symb, Entry);
300     Res = Entry->Type & MachO::NlistMaskExternal;
301   } else {
302     InMemoryStruct<macho::SymbolTableEntry> Entry;
303     getSymbolTableEntry(Symb, Entry);
304     Res = Entry->Type & MachO::NlistMaskExternal;
305   }
306   return object_error::success;
307 }
308 
309 error_code MachOObjectFile::getSymbolType(DataRefImpl Symb,
310                                           SymbolRef::SymbolType &Res) const {
311   uint8_t n_type;
312   if (MachOObj->is64Bit()) {
313     InMemoryStruct<macho::Symbol64TableEntry> Entry;
314     getSymbol64TableEntry(Symb, Entry);
315     n_type = Entry->Type;
316   } else {
317     InMemoryStruct<macho::SymbolTableEntry> Entry;
318     getSymbolTableEntry(Symb, Entry);
319     n_type = Entry->Type;
320   }
321   Res = SymbolRef::ST_Other;
322   switch (n_type & MachO::NlistMaskType) {
323     case MachO::NListTypeUndefined :
324       Res = SymbolRef::ST_External;
325       break;
326     case MachO::NListTypeSection :
327       Res = SymbolRef::ST_Function;
328       break;
329   }
330   return object_error::success;
331 }
332 
333 
334 symbol_iterator MachOObjectFile::begin_symbols() const {
335   // DRI.d.a = segment number; DRI.d.b = symbol index.
336   DataRefImpl DRI;
337   DRI.d.a = DRI.d.b = 0;
338   moveToNextSymbol(DRI);
339   return symbol_iterator(SymbolRef(DRI, this));
340 }
341 
342 symbol_iterator MachOObjectFile::end_symbols() const {
343   DataRefImpl DRI;
344   DRI.d.a = MachOObj->getHeader().NumLoadCommands;
345   DRI.d.b = 0;
346   return symbol_iterator(SymbolRef(DRI, this));
347 }
348 
349 
350 /*===-- Sections ----------------------------------------------------------===*/
351 
352 void MachOObjectFile::moveToNextSection(DataRefImpl &DRI) const {
353   uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
354   while (DRI.d.a < LoadCommandCount) {
355     LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
356     if (LCI.Command.Type == macho::LCT_Segment) {
357       InMemoryStruct<macho::SegmentLoadCommand> SegmentLoadCmd;
358       MachOObj->ReadSegmentLoadCommand(LCI, SegmentLoadCmd);
359       if (DRI.d.b < SegmentLoadCmd->NumSections)
360         return;
361     } else if (LCI.Command.Type == macho::LCT_Segment64) {
362       InMemoryStruct<macho::Segment64LoadCommand> Segment64LoadCmd;
363       MachOObj->ReadSegment64LoadCommand(LCI, Segment64LoadCmd);
364       if (DRI.d.b < Segment64LoadCmd->NumSections)
365         return;
366     }
367 
368     DRI.d.a++;
369     DRI.d.b = 0;
370   }
371 }
372 
373 error_code MachOObjectFile::getSectionNext(DataRefImpl DRI,
374                                            SectionRef &Result) const {
375   DRI.d.b++;
376   moveToNextSection(DRI);
377   Result = SectionRef(DRI, this);
378   return object_error::success;
379 }
380 
381 void
382 MachOObjectFile::getSection(DataRefImpl DRI,
383                             InMemoryStruct<macho::Section> &Res) const {
384   InMemoryStruct<macho::SegmentLoadCommand> SLC;
385   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
386   MachOObj->ReadSegmentLoadCommand(LCI, SLC);
387   MachOObj->ReadSection(LCI, DRI.d.b, Res);
388 }
389 
390 std::size_t MachOObjectFile::getSectionIndex(DataRefImpl Sec) const {
391   SectionList::const_iterator loc =
392     std::find(Sections.begin(), Sections.end(), Sec);
393   assert(loc != Sections.end() && "Sec is not a valid section!");
394   return std::distance(Sections.begin(), loc);
395 }
396 
397 void
398 MachOObjectFile::getSection64(DataRefImpl DRI,
399                             InMemoryStruct<macho::Section64> &Res) const {
400   InMemoryStruct<macho::Segment64LoadCommand> SLC;
401   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
402   MachOObj->ReadSegment64LoadCommand(LCI, SLC);
403   MachOObj->ReadSection64(LCI, DRI.d.b, Res);
404 }
405 
406 static bool is64BitLoadCommand(const MachOObject *MachOObj, DataRefImpl DRI) {
407   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
408   if (LCI.Command.Type == macho::LCT_Segment64)
409     return true;
410   assert(LCI.Command.Type == macho::LCT_Segment && "Unexpected Type.");
411   return false;
412 }
413 
414 error_code MachOObjectFile::getSectionName(DataRefImpl DRI,
415                                            StringRef &Result) const {
416   // FIXME: thread safety.
417   static char result[34];
418   if (is64BitLoadCommand(MachOObj, DRI)) {
419     InMemoryStruct<macho::Segment64LoadCommand> SLC;
420     LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
421     MachOObj->ReadSegment64LoadCommand(LCI, SLC);
422     InMemoryStruct<macho::Section64> Sect;
423     MachOObj->ReadSection64(LCI, DRI.d.b, Sect);
424 
425     strcpy(result, Sect->SegmentName);
426     strcat(result, ",");
427     strcat(result, Sect->Name);
428   } else {
429     InMemoryStruct<macho::SegmentLoadCommand> SLC;
430     LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
431     MachOObj->ReadSegmentLoadCommand(LCI, SLC);
432     InMemoryStruct<macho::Section> Sect;
433     MachOObj->ReadSection(LCI, DRI.d.b, Sect);
434 
435     strcpy(result, Sect->SegmentName);
436     strcat(result, ",");
437     strcat(result, Sect->Name);
438   }
439   Result = StringRef(result);
440   return object_error::success;
441 }
442 
443 error_code MachOObjectFile::getSectionAddress(DataRefImpl DRI,
444                                               uint64_t &Result) const {
445   if (is64BitLoadCommand(MachOObj, DRI)) {
446     InMemoryStruct<macho::Section64> Sect;
447     getSection64(DRI, Sect);
448     Result = Sect->Address;
449   } else {
450     InMemoryStruct<macho::Section> Sect;
451     getSection(DRI, Sect);
452     Result = Sect->Address;
453   }
454   return object_error::success;
455 }
456 
457 error_code MachOObjectFile::getSectionSize(DataRefImpl DRI,
458                                            uint64_t &Result) const {
459   if (is64BitLoadCommand(MachOObj, DRI)) {
460     InMemoryStruct<macho::Section64> Sect;
461     getSection64(DRI, Sect);
462     Result = Sect->Size;
463   } else {
464     InMemoryStruct<macho::Section> Sect;
465     getSection(DRI, Sect);
466     Result = Sect->Size;
467   }
468   return object_error::success;
469 }
470 
471 error_code MachOObjectFile::getSectionContents(DataRefImpl DRI,
472                                                StringRef &Result) const {
473   if (is64BitLoadCommand(MachOObj, DRI)) {
474     InMemoryStruct<macho::Section64> Sect;
475     getSection64(DRI, Sect);
476     Result = MachOObj->getData(Sect->Offset, Sect->Size);
477   } else {
478     InMemoryStruct<macho::Section> Sect;
479     getSection(DRI, Sect);
480     Result = MachOObj->getData(Sect->Offset, Sect->Size);
481   }
482   return object_error::success;
483 }
484 
485 error_code MachOObjectFile::getSectionAlignment(DataRefImpl DRI,
486                                                 uint64_t &Result) const {
487   if (is64BitLoadCommand(MachOObj, DRI)) {
488     InMemoryStruct<macho::Section64> Sect;
489     getSection64(DRI, Sect);
490     Result = uint64_t(1) << Sect->Align;
491   } else {
492     InMemoryStruct<macho::Section> Sect;
493     getSection(DRI, Sect);
494     Result = uint64_t(1) << Sect->Align;
495   }
496   return object_error::success;
497 }
498 
499 error_code MachOObjectFile::isSectionText(DataRefImpl DRI,
500                                           bool &Result) const {
501   if (is64BitLoadCommand(MachOObj, DRI)) {
502     InMemoryStruct<macho::Section64> Sect;
503     getSection64(DRI, Sect);
504     Result = !strcmp(Sect->Name, "__text");
505   } else {
506     InMemoryStruct<macho::Section> Sect;
507     getSection(DRI, Sect);
508     Result = !strcmp(Sect->Name, "__text");
509   }
510   return object_error::success;
511 }
512 
513 error_code MachOObjectFile::isSectionData(DataRefImpl DRI,
514                                           bool &Result) const {
515   // FIXME: Unimplemented.
516   Result = false;
517   return object_error::success;
518 }
519 
520 error_code MachOObjectFile::isSectionBSS(DataRefImpl DRI,
521                                          bool &Result) const {
522   // FIXME: Unimplemented.
523   Result = false;
524   return object_error::success;
525 }
526 
527 error_code MachOObjectFile::sectionContainsSymbol(DataRefImpl Sec,
528                                                   DataRefImpl Symb,
529                                                   bool &Result) const {
530   if (MachOObj->is64Bit()) {
531     InMemoryStruct<macho::Symbol64TableEntry> Entry;
532     getSymbol64TableEntry(Symb, Entry);
533     Result = Entry->SectionIndex == 1 + Sec.d.a + Sec.d.b;
534   } else {
535     InMemoryStruct<macho::SymbolTableEntry> Entry;
536     getSymbolTableEntry(Symb, Entry);
537     Result = Entry->SectionIndex == 1 + Sec.d.a + Sec.d.b;
538   }
539   return object_error::success;
540 }
541 
542 relocation_iterator MachOObjectFile::getSectionRelBegin(DataRefImpl Sec) const {
543   DataRefImpl ret;
544   ret.d.a = 0;
545   ret.d.b = getSectionIndex(Sec);
546   return relocation_iterator(RelocationRef(ret, this));
547 }
548 relocation_iterator MachOObjectFile::getSectionRelEnd(DataRefImpl Sec) const {
549   uint32_t last_reloc;
550   if (is64BitLoadCommand(MachOObj, Sec)) {
551     InMemoryStruct<macho::Section64> Sect;
552     getSection64(Sec, Sect);
553     last_reloc = Sect->NumRelocationTableEntries;
554   } else {
555     InMemoryStruct<macho::Section> Sect;
556     getSection(Sec, Sect);
557     last_reloc = Sect->NumRelocationTableEntries;
558   }
559   DataRefImpl ret;
560   ret.d.a = last_reloc;
561   ret.d.b = getSectionIndex(Sec);
562   return relocation_iterator(RelocationRef(ret, this));
563 }
564 
565 section_iterator MachOObjectFile::begin_sections() const {
566   DataRefImpl DRI;
567   DRI.d.a = DRI.d.b = 0;
568   moveToNextSection(DRI);
569   return section_iterator(SectionRef(DRI, this));
570 }
571 
572 section_iterator MachOObjectFile::end_sections() const {
573   DataRefImpl DRI;
574   DRI.d.a = MachOObj->getHeader().NumLoadCommands;
575   DRI.d.b = 0;
576   return section_iterator(SectionRef(DRI, this));
577 }
578 
579 /*===-- Relocations -------------------------------------------------------===*/
580 
581 void MachOObjectFile::
582 getRelocation(DataRefImpl Rel,
583               InMemoryStruct<macho::RelocationEntry> &Res) const {
584   uint32_t relOffset;
585   if (MachOObj->is64Bit()) {
586     InMemoryStruct<macho::Section64> Sect;
587     getSection64(Sections[Rel.d.b], Sect);
588     relOffset = Sect->RelocationTableOffset;
589   } else {
590     InMemoryStruct<macho::Section> Sect;
591     getSection(Sections[Rel.d.b], Sect);
592     relOffset = Sect->RelocationTableOffset;
593   }
594   MachOObj->ReadRelocationEntry(relOffset, Rel.d.a, Res);
595 }
596 error_code MachOObjectFile::getRelocationNext(DataRefImpl Rel,
597                                               RelocationRef &Res) const {
598   ++Rel.d.a;
599   Res = RelocationRef(Rel, this);
600   return object_error::success;
601 }
602 error_code MachOObjectFile::getRelocationAddress(DataRefImpl Rel,
603                                                  uint64_t &Res) const {
604   const uint8_t* sectAddress = base();
605   if (MachOObj->is64Bit()) {
606     InMemoryStruct<macho::Section64> Sect;
607     getSection64(Sections[Rel.d.b], Sect);
608     sectAddress += Sect->Offset;
609   } else {
610     InMemoryStruct<macho::Section> Sect;
611     getSection(Sections[Rel.d.b], Sect);
612     sectAddress += Sect->Offset;
613   }
614   InMemoryStruct<macho::RelocationEntry> RE;
615   getRelocation(Rel, RE);
616   Res = reinterpret_cast<uintptr_t>(sectAddress + RE->Word0);
617   return object_error::success;
618 }
619 error_code MachOObjectFile::getRelocationSymbol(DataRefImpl Rel,
620                                                 SymbolRef &Res) const {
621   InMemoryStruct<macho::RelocationEntry> RE;
622   getRelocation(Rel, RE);
623   uint32_t SymbolIdx = RE->Word1 & 0xffffff;
624   bool isExtern = (RE->Word1 >> 27) & 1;
625 
626   DataRefImpl Sym;
627   Sym.d.a = Sym.d.b = 0;
628   moveToNextSymbol(Sym);
629   if (isExtern) {
630     for (unsigned i = 0; i < SymbolIdx; i++) {
631       Sym.d.b++;
632       moveToNextSymbol(Sym);
633       assert(Sym.d.a < MachOObj->getHeader().NumLoadCommands &&
634              "Relocation symbol index out of range!");
635     }
636   }
637   Res = SymbolRef(Sym, this);
638   return object_error::success;
639 }
640 error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
641                                               uint32_t &Res) const {
642   InMemoryStruct<macho::RelocationEntry> RE;
643   getRelocation(Rel, RE);
644   Res = RE->Word1;
645   return object_error::success;
646 }
647 error_code MachOObjectFile::getRelocationTypeName(DataRefImpl Rel,
648                                           SmallVectorImpl<char> &Result) const {
649   return object_error::success;
650 }
651 error_code MachOObjectFile::getRelocationAdditionalInfo(DataRefImpl Rel,
652                                                         int64_t &Res) const {
653   InMemoryStruct<macho::RelocationEntry> RE;
654   getRelocation(Rel, RE);
655   bool isExtern = (RE->Word1 >> 27) & 1;
656   Res = 0;
657   if (!isExtern) {
658     const uint8_t* sectAddress = base();
659     if (MachOObj->is64Bit()) {
660       InMemoryStruct<macho::Section64> Sect;
661       getSection64(Sections[Rel.d.b], Sect);
662       sectAddress += Sect->Offset;
663     } else {
664       InMemoryStruct<macho::Section> Sect;
665       getSection(Sections[Rel.d.b], Sect);
666       sectAddress += Sect->Offset;
667     }
668     Res = reinterpret_cast<uintptr_t>(sectAddress);
669   }
670   return object_error::success;
671 }
672 error_code MachOObjectFile::getRelocationValueString(DataRefImpl Rel,
673                                           SmallVectorImpl<char> &Result) const {
674   return object_error::success;
675 }
676 
677 /*===-- Miscellaneous -----------------------------------------------------===*/
678 
679 uint8_t MachOObjectFile::getBytesInAddress() const {
680   return MachOObj->is64Bit() ? 8 : 4;
681 }
682 
683 StringRef MachOObjectFile::getFileFormatName() const {
684   if (!MachOObj->is64Bit()) {
685     switch (MachOObj->getHeader().CPUType) {
686     case llvm::MachO::CPUTypeI386:
687       return "Mach-O 32-bit i386";
688     case llvm::MachO::CPUTypeARM:
689       return "Mach-O arm";
690     case llvm::MachO::CPUTypePowerPC:
691       return "Mach-O 32-bit ppc";
692     default:
693       assert((MachOObj->getHeader().CPUType & llvm::MachO::CPUArchABI64) == 0 &&
694              "64-bit object file when we're not 64-bit?");
695       return "Mach-O 32-bit unknown";
696     }
697   }
698 
699   switch (MachOObj->getHeader().CPUType) {
700   case llvm::MachO::CPUTypeX86_64:
701     return "Mach-O 64-bit x86-64";
702   case llvm::MachO::CPUTypePowerPC64:
703     return "Mach-O 64-bit ppc64";
704   default:
705     assert((MachOObj->getHeader().CPUType & llvm::MachO::CPUArchABI64) == 1 &&
706            "32-bit object file when we're 64-bit?");
707     return "Mach-O 64-bit unknown";
708   }
709 }
710 
711 unsigned MachOObjectFile::getArch() const {
712   switch (MachOObj->getHeader().CPUType) {
713   case llvm::MachO::CPUTypeI386:
714     return Triple::x86;
715   case llvm::MachO::CPUTypeX86_64:
716     return Triple::x86_64;
717   case llvm::MachO::CPUTypeARM:
718     return Triple::arm;
719   case llvm::MachO::CPUTypePowerPC:
720     return Triple::ppc;
721   case llvm::MachO::CPUTypePowerPC64:
722     return Triple::ppc64;
723   default:
724     return Triple::UnknownArch;
725   }
726 }
727 
728 } // end namespace llvm
729