1//===- ObjectFile.h - File format independent object file -------*- 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 declares a file format independent ObjectFile class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_OBJECT_OBJECTFILE_H
15#define LLVM_OBJECT_OBJECTFILE_H
16
17#include "llvm/ADT/StringRef.h"
18#include "llvm/Object/SymbolicFile.h"
19#include "llvm/Support/DataTypes.h"
20#include "llvm/Support/ErrorHandling.h"
21#include "llvm/Support/FileSystem.h"
22#include "llvm/Support/MemoryBuffer.h"
23#include <cstring>
24#include <vector>
25
26namespace llvm {
27namespace object {
28
29class ObjectFile;
30class COFFObjectFile;
31class MachOObjectFile;
32
33class SymbolRef;
34class symbol_iterator;
35
36/// RelocationRef - This is a value type class that represents a single
37/// relocation in the list of relocations in the object file.
38class RelocationRef {
39  DataRefImpl RelocationPimpl;
40  const ObjectFile *OwningObject;
41
42public:
43  RelocationRef() : OwningObject(nullptr) { }
44
45  RelocationRef(DataRefImpl RelocationP, const ObjectFile *Owner);
46
47  bool operator==(const RelocationRef &Other) const;
48
49  void moveNext();
50
51  std::error_code getAddress(uint64_t &Result) const;
52  std::error_code getOffset(uint64_t &Result) const;
53  symbol_iterator getSymbol() const;
54  std::error_code getType(uint64_t &Result) const;
55
56  /// @brief Indicates whether this relocation should hidden when listing
57  /// relocations, usually because it is the trailing part of a multipart
58  /// relocation that will be printed as part of the leading relocation.
59  std::error_code getHidden(bool &Result) const;
60
61  /// @brief Get a string that represents the type of this relocation.
62  ///
63  /// This is for display purposes only.
64  std::error_code getTypeName(SmallVectorImpl<char> &Result) const;
65
66  /// @brief Get a string that represents the calculation of the value of this
67  ///        relocation.
68  ///
69  /// This is for display purposes only.
70  std::error_code getValueString(SmallVectorImpl<char> &Result) const;
71
72  DataRefImpl getRawDataRefImpl() const;
73  const ObjectFile *getObjectFile() const;
74};
75typedef content_iterator<RelocationRef> relocation_iterator;
76
77/// SectionRef - This is a value type class that represents a single section in
78/// the list of sections in the object file.
79class SectionRef;
80typedef content_iterator<SectionRef> section_iterator;
81class SectionRef {
82  friend class SymbolRef;
83  DataRefImpl SectionPimpl;
84  const ObjectFile *OwningObject;
85
86public:
87  SectionRef() : OwningObject(nullptr) { }
88
89  SectionRef(DataRefImpl SectionP, const ObjectFile *Owner);
90
91  bool operator==(const SectionRef &Other) const;
92  bool operator!=(const SectionRef &Other) const;
93  bool operator<(const SectionRef &Other) const;
94
95  void moveNext();
96
97  std::error_code getName(StringRef &Result) const;
98  uint64_t getAddress() const;
99  uint64_t getSize() const;
100  std::error_code getContents(StringRef &Result) const;
101
102  /// @brief Get the alignment of this section as the actual value (not log 2).
103  uint64_t getAlignment() const;
104
105  bool isText() const;
106  bool isData() const;
107  bool isBSS() const;
108  bool isVirtual() const;
109
110  bool containsSymbol(SymbolRef S) const;
111
112  relocation_iterator relocation_begin() const;
113  relocation_iterator relocation_end() const;
114  iterator_range<relocation_iterator> relocations() const {
115    return iterator_range<relocation_iterator>(relocation_begin(),
116                                               relocation_end());
117  }
118  section_iterator getRelocatedSection() const;
119
120  DataRefImpl getRawDataRefImpl() const;
121  const ObjectFile *getObject() const;
122};
123
124/// SymbolRef - This is a value type class that represents a single symbol in
125/// the list of symbols in the object file.
126class SymbolRef : public BasicSymbolRef {
127  friend class SectionRef;
128
129public:
130  SymbolRef() : BasicSymbolRef() {}
131
132  enum Type {
133    ST_Unknown, // Type not specified
134    ST_Data,
135    ST_Debug,
136    ST_File,
137    ST_Function,
138    ST_Other
139  };
140
141  SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner);
142
143  std::error_code getName(StringRef &Result) const;
144  /// Returns the symbol virtual address (i.e. address at which it will be
145  /// mapped).
146  std::error_code getAddress(uint64_t &Result) const;
147  /// @brief Get the alignment of this symbol as the actual value (not log 2).
148  std::error_code getAlignment(uint32_t &Result) const;
149  std::error_code getSize(uint64_t &Result) const;
150  std::error_code getType(SymbolRef::Type &Result) const;
151  std::error_code getOther(uint8_t &Result) const;
152
153  /// @brief Get section this symbol is defined in reference to. Result is
154  /// end_sections() if it is undefined or is an absolute symbol.
155  std::error_code getSection(section_iterator &Result) const;
156
157  const ObjectFile *getObject() const;
158};
159
160class symbol_iterator : public basic_symbol_iterator {
161public:
162  symbol_iterator(SymbolRef Sym) : basic_symbol_iterator(Sym) {}
163  symbol_iterator(const basic_symbol_iterator &B)
164      : basic_symbol_iterator(SymbolRef(B->getRawDataRefImpl(),
165                                        cast<ObjectFile>(B->getObject()))) {}
166
167  const SymbolRef *operator->() const {
168    const BasicSymbolRef &P = basic_symbol_iterator::operator *();
169    return static_cast<const SymbolRef*>(&P);
170  }
171
172  const SymbolRef &operator*() const {
173    const BasicSymbolRef &P = basic_symbol_iterator::operator *();
174    return static_cast<const SymbolRef&>(P);
175  }
176};
177
178/// ObjectFile - This class is the base class for all object file types.
179/// Concrete instances of this object are created by createObjectFile, which
180/// figures out which type to create.
181class ObjectFile : public SymbolicFile {
182  virtual void anchor();
183  ObjectFile() = delete;
184  ObjectFile(const ObjectFile &other) = delete;
185
186protected:
187  ObjectFile(unsigned int Type, MemoryBufferRef Source);
188
189  const uint8_t *base() const {
190    return reinterpret_cast<const uint8_t *>(Data.getBufferStart());
191  }
192
193  // These functions are for SymbolRef to call internally. The main goal of
194  // this is to allow SymbolRef::SymbolPimpl to point directly to the symbol
195  // entry in the memory mapped object file. SymbolPimpl cannot contain any
196  // virtual functions because then it could not point into the memory mapped
197  // file.
198  //
199  // Implementations assume that the DataRefImpl is valid and has not been
200  // modified externally. It's UB otherwise.
201  friend class SymbolRef;
202  virtual std::error_code getSymbolName(DataRefImpl Symb,
203                                        StringRef &Res) const = 0;
204  std::error_code printSymbolName(raw_ostream &OS,
205                                  DataRefImpl Symb) const override;
206  virtual std::error_code getSymbolAddress(DataRefImpl Symb,
207                                           uint64_t &Res) const = 0;
208  virtual std::error_code getSymbolAlignment(DataRefImpl Symb,
209                                             uint32_t &Res) const;
210  virtual std::error_code getSymbolSize(DataRefImpl Symb,
211                                        uint64_t &Res) const = 0;
212  virtual std::error_code getSymbolType(DataRefImpl Symb,
213                                        SymbolRef::Type &Res) const = 0;
214  virtual std::error_code getSymbolSection(DataRefImpl Symb,
215                                           section_iterator &Res) const = 0;
216  virtual std::error_code getSymbolOther(DataRefImpl Symb,
217                                         uint8_t &Res) const {
218    return object_error::invalid_file_type;
219  }
220
221  // Same as above for SectionRef.
222  friend class SectionRef;
223  virtual void moveSectionNext(DataRefImpl &Sec) const = 0;
224  virtual std::error_code getSectionName(DataRefImpl Sec,
225                                         StringRef &Res) const = 0;
226  virtual uint64_t getSectionAddress(DataRefImpl Sec) const = 0;
227  virtual uint64_t getSectionSize(DataRefImpl Sec) const = 0;
228  virtual std::error_code getSectionContents(DataRefImpl Sec,
229                                             StringRef &Res) const = 0;
230  virtual uint64_t getSectionAlignment(DataRefImpl Sec) const = 0;
231  virtual bool isSectionText(DataRefImpl Sec) const = 0;
232  virtual bool isSectionData(DataRefImpl Sec) const = 0;
233  virtual bool isSectionBSS(DataRefImpl Sec) const = 0;
234  // A section is 'virtual' if its contents aren't present in the object image.
235  virtual bool isSectionVirtual(DataRefImpl Sec) const = 0;
236  virtual bool sectionContainsSymbol(DataRefImpl Sec,
237                                     DataRefImpl Symb) const = 0;
238  virtual relocation_iterator section_rel_begin(DataRefImpl Sec) const = 0;
239  virtual relocation_iterator section_rel_end(DataRefImpl Sec) const = 0;
240  virtual section_iterator getRelocatedSection(DataRefImpl Sec) const;
241
242  // Same as above for RelocationRef.
243  friend class RelocationRef;
244  virtual void moveRelocationNext(DataRefImpl &Rel) const = 0;
245  virtual std::error_code getRelocationAddress(DataRefImpl Rel,
246                                               uint64_t &Res) const = 0;
247  virtual std::error_code getRelocationOffset(DataRefImpl Rel,
248                                              uint64_t &Res) const = 0;
249  virtual symbol_iterator getRelocationSymbol(DataRefImpl Rel) const = 0;
250  virtual std::error_code getRelocationType(DataRefImpl Rel,
251                                            uint64_t &Res) const = 0;
252  virtual std::error_code
253  getRelocationTypeName(DataRefImpl Rel,
254                        SmallVectorImpl<char> &Result) const = 0;
255  virtual std::error_code
256  getRelocationValueString(DataRefImpl Rel,
257                           SmallVectorImpl<char> &Result) const = 0;
258  virtual std::error_code getRelocationHidden(DataRefImpl Rel,
259                                              bool &Result) const {
260    Result = false;
261    return object_error::success;
262  }
263
264public:
265  typedef iterator_range<symbol_iterator> symbol_iterator_range;
266  symbol_iterator_range symbols() const {
267    return symbol_iterator_range(symbol_begin(), symbol_end());
268  }
269
270  virtual section_iterator section_begin() const = 0;
271  virtual section_iterator section_end() const = 0;
272
273  typedef iterator_range<section_iterator> section_iterator_range;
274  section_iterator_range sections() const {
275    return section_iterator_range(section_begin(), section_end());
276  }
277
278  /// @brief The number of bytes used to represent an address in this object
279  ///        file format.
280  virtual uint8_t getBytesInAddress() const = 0;
281
282  virtual StringRef getFileFormatName() const = 0;
283  virtual /* Triple::ArchType */ unsigned getArch() const = 0;
284
285  /// Returns platform-specific object flags, if any.
286  virtual std::error_code getPlatformFlags(unsigned &Result) const {
287    Result = 0;
288    return object_error::invalid_file_type;
289  }
290
291  /// True if this is a relocatable object (.o/.obj).
292  virtual bool isRelocatableObject() const = 0;
293
294  /// @returns Pointer to ObjectFile subclass to handle this type of object.
295  /// @param ObjectPath The path to the object file. ObjectPath.isObject must
296  ///        return true.
297  /// @brief Create ObjectFile from path.
298  static ErrorOr<OwningBinary<ObjectFile>>
299  createObjectFile(StringRef ObjectPath);
300
301  static ErrorOr<std::unique_ptr<ObjectFile>>
302  createObjectFile(MemoryBufferRef Object, sys::fs::file_magic Type);
303  static ErrorOr<std::unique_ptr<ObjectFile>>
304  createObjectFile(MemoryBufferRef Object) {
305    return createObjectFile(Object, sys::fs::file_magic::unknown);
306  }
307
308
309  static inline bool classof(const Binary *v) {
310    return v->isObject();
311  }
312
313  static ErrorOr<std::unique_ptr<COFFObjectFile>>
314  createCOFFObjectFile(MemoryBufferRef Object);
315
316  static ErrorOr<std::unique_ptr<ObjectFile>>
317  createELFObjectFile(MemoryBufferRef Object);
318
319  static ErrorOr<std::unique_ptr<MachOObjectFile>>
320  createMachOObjectFile(MemoryBufferRef Object);
321};
322
323// Inline function definitions.
324inline SymbolRef::SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner)
325    : BasicSymbolRef(SymbolP, Owner) {}
326
327inline std::error_code SymbolRef::getName(StringRef &Result) const {
328  return getObject()->getSymbolName(getRawDataRefImpl(), Result);
329}
330
331inline std::error_code SymbolRef::getAddress(uint64_t &Result) const {
332  return getObject()->getSymbolAddress(getRawDataRefImpl(), Result);
333}
334
335inline std::error_code SymbolRef::getAlignment(uint32_t &Result) const {
336  return getObject()->getSymbolAlignment(getRawDataRefImpl(), Result);
337}
338
339inline std::error_code SymbolRef::getSize(uint64_t &Result) const {
340  return getObject()->getSymbolSize(getRawDataRefImpl(), Result);
341}
342
343inline std::error_code SymbolRef::getSection(section_iterator &Result) const {
344  return getObject()->getSymbolSection(getRawDataRefImpl(), Result);
345}
346
347inline std::error_code SymbolRef::getType(SymbolRef::Type &Result) const {
348  return getObject()->getSymbolType(getRawDataRefImpl(), Result);
349}
350
351inline std::error_code SymbolRef::getOther(uint8_t &Result) const {
352  return getObject()->getSymbolOther(getRawDataRefImpl(), Result);
353}
354
355inline const ObjectFile *SymbolRef::getObject() const {
356  const SymbolicFile *O = BasicSymbolRef::getObject();
357  return cast<ObjectFile>(O);
358}
359
360
361/// SectionRef
362inline SectionRef::SectionRef(DataRefImpl SectionP,
363                              const ObjectFile *Owner)
364  : SectionPimpl(SectionP)
365  , OwningObject(Owner) {}
366
367inline bool SectionRef::operator==(const SectionRef &Other) const {
368  return SectionPimpl == Other.SectionPimpl;
369}
370
371inline bool SectionRef::operator!=(const SectionRef &Other) const {
372  return SectionPimpl != Other.SectionPimpl;
373}
374
375inline bool SectionRef::operator<(const SectionRef &Other) const {
376  return SectionPimpl < Other.SectionPimpl;
377}
378
379inline void SectionRef::moveNext() {
380  return OwningObject->moveSectionNext(SectionPimpl);
381}
382
383inline std::error_code SectionRef::getName(StringRef &Result) const {
384  return OwningObject->getSectionName(SectionPimpl, Result);
385}
386
387inline uint64_t SectionRef::getAddress() const {
388  return OwningObject->getSectionAddress(SectionPimpl);
389}
390
391inline uint64_t SectionRef::getSize() const {
392  return OwningObject->getSectionSize(SectionPimpl);
393}
394
395inline std::error_code SectionRef::getContents(StringRef &Result) const {
396  return OwningObject->getSectionContents(SectionPimpl, Result);
397}
398
399inline uint64_t SectionRef::getAlignment() const {
400  return OwningObject->getSectionAlignment(SectionPimpl);
401}
402
403inline bool SectionRef::isText() const {
404  return OwningObject->isSectionText(SectionPimpl);
405}
406
407inline bool SectionRef::isData() const {
408  return OwningObject->isSectionData(SectionPimpl);
409}
410
411inline bool SectionRef::isBSS() const {
412  return OwningObject->isSectionBSS(SectionPimpl);
413}
414
415inline bool SectionRef::isVirtual() const {
416  return OwningObject->isSectionVirtual(SectionPimpl);
417}
418
419inline bool SectionRef::containsSymbol(SymbolRef S) const {
420  return OwningObject->sectionContainsSymbol(SectionPimpl,
421                                             S.getRawDataRefImpl());
422}
423
424inline relocation_iterator SectionRef::relocation_begin() const {
425  return OwningObject->section_rel_begin(SectionPimpl);
426}
427
428inline relocation_iterator SectionRef::relocation_end() const {
429  return OwningObject->section_rel_end(SectionPimpl);
430}
431
432inline section_iterator SectionRef::getRelocatedSection() const {
433  return OwningObject->getRelocatedSection(SectionPimpl);
434}
435
436inline DataRefImpl SectionRef::getRawDataRefImpl() const {
437  return SectionPimpl;
438}
439
440inline const ObjectFile *SectionRef::getObject() const {
441  return OwningObject;
442}
443
444/// RelocationRef
445inline RelocationRef::RelocationRef(DataRefImpl RelocationP,
446                              const ObjectFile *Owner)
447  : RelocationPimpl(RelocationP)
448  , OwningObject(Owner) {}
449
450inline bool RelocationRef::operator==(const RelocationRef &Other) const {
451  return RelocationPimpl == Other.RelocationPimpl;
452}
453
454inline void RelocationRef::moveNext() {
455  return OwningObject->moveRelocationNext(RelocationPimpl);
456}
457
458inline std::error_code RelocationRef::getAddress(uint64_t &Result) const {
459  return OwningObject->getRelocationAddress(RelocationPimpl, Result);
460}
461
462inline std::error_code RelocationRef::getOffset(uint64_t &Result) const {
463  return OwningObject->getRelocationOffset(RelocationPimpl, Result);
464}
465
466inline symbol_iterator RelocationRef::getSymbol() const {
467  return OwningObject->getRelocationSymbol(RelocationPimpl);
468}
469
470inline std::error_code RelocationRef::getType(uint64_t &Result) const {
471  return OwningObject->getRelocationType(RelocationPimpl, Result);
472}
473
474inline std::error_code
475RelocationRef::getTypeName(SmallVectorImpl<char> &Result) const {
476  return OwningObject->getRelocationTypeName(RelocationPimpl, Result);
477}
478
479inline std::error_code
480RelocationRef::getValueString(SmallVectorImpl<char> &Result) const {
481  return OwningObject->getRelocationValueString(RelocationPimpl, Result);
482}
483
484inline std::error_code RelocationRef::getHidden(bool &Result) const {
485  return OwningObject->getRelocationHidden(RelocationPimpl, Result);
486}
487
488inline DataRefImpl RelocationRef::getRawDataRefImpl() const {
489  return RelocationPimpl;
490}
491
492inline const ObjectFile *RelocationRef::getObjectFile() const {
493  return OwningObject;
494}
495
496
497} // end namespace object
498} // end namespace llvm
499
500#endif
501