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
26 namespace llvm {
27 namespace object {
28
29 class ObjectFile;
30
31 class SymbolRef;
32 class symbol_iterator;
33
34 /// RelocationRef - This is a value type class that represents a single
35 /// relocation in the list of relocations in the object file.
36 class RelocationRef {
37 DataRefImpl RelocationPimpl;
38 const ObjectFile *OwningObject;
39
40 public:
RelocationRef()41 RelocationRef() : OwningObject(nullptr) { }
42
43 RelocationRef(DataRefImpl RelocationP, const ObjectFile *Owner);
44
45 bool operator==(const RelocationRef &Other) const;
46
47 void moveNext();
48
49 std::error_code getAddress(uint64_t &Result) const;
50 std::error_code getOffset(uint64_t &Result) const;
51 symbol_iterator getSymbol() const;
52 std::error_code getType(uint64_t &Result) const;
53
54 /// @brief Indicates whether this relocation should hidden when listing
55 /// relocations, usually because it is the trailing part of a multipart
56 /// relocation that will be printed as part of the leading relocation.
57 std::error_code getHidden(bool &Result) const;
58
59 /// @brief Get a string that represents the type of this relocation.
60 ///
61 /// This is for display purposes only.
62 std::error_code getTypeName(SmallVectorImpl<char> &Result) const;
63
64 /// @brief Get a string that represents the calculation of the value of this
65 /// relocation.
66 ///
67 /// This is for display purposes only.
68 std::error_code getValueString(SmallVectorImpl<char> &Result) const;
69
70 DataRefImpl getRawDataRefImpl() const;
71 const ObjectFile *getObjectFile() const;
72 };
73 typedef content_iterator<RelocationRef> relocation_iterator;
74
75 /// SectionRef - This is a value type class that represents a single section in
76 /// the list of sections in the object file.
77 class SectionRef;
78 typedef content_iterator<SectionRef> section_iterator;
79 class SectionRef {
80 friend class SymbolRef;
81 DataRefImpl SectionPimpl;
82 const ObjectFile *OwningObject;
83
84 public:
SectionRef()85 SectionRef() : OwningObject(nullptr) { }
86
87 SectionRef(DataRefImpl SectionP, const ObjectFile *Owner);
88
89 bool operator==(const SectionRef &Other) const;
90 bool operator!=(const SectionRef &Other) const;
91 bool operator<(const SectionRef &Other) const;
92
93 void moveNext();
94
95 std::error_code getName(StringRef &Result) const;
96 std::error_code getAddress(uint64_t &Result) const;
97 std::error_code getSize(uint64_t &Result) const;
98 std::error_code getContents(StringRef &Result) const;
99
100 /// @brief Get the alignment of this section as the actual value (not log 2).
101 std::error_code getAlignment(uint64_t &Result) const;
102
103 // FIXME: Move to the normalization layer when it's created.
104 std::error_code isText(bool &Result) const;
105 std::error_code isData(bool &Result) const;
106 std::error_code isBSS(bool &Result) const;
107 std::error_code isRequiredForExecution(bool &Result) const;
108 std::error_code isVirtual(bool &Result) const;
109 std::error_code isZeroInit(bool &Result) const;
110 std::error_code isReadOnlyData(bool &Result) const;
111
112 std::error_code containsSymbol(SymbolRef S, bool &Result) const;
113
114 relocation_iterator relocation_begin() const;
115 relocation_iterator relocation_end() const;
relocations()116 iterator_range<relocation_iterator> relocations() const {
117 return iterator_range<relocation_iterator>(relocation_begin(),
118 relocation_end());
119 }
120 section_iterator getRelocatedSection() const;
121
122 DataRefImpl getRawDataRefImpl() const;
123 };
124
125 /// SymbolRef - This is a value type class that represents a single symbol in
126 /// the list of symbols in the object file.
127 class SymbolRef : public BasicSymbolRef {
128 friend class SectionRef;
129
130 public:
SymbolRef()131 SymbolRef() : BasicSymbolRef() {}
132
133 enum Type {
134 ST_Unknown, // Type not specified
135 ST_Data,
136 ST_Debug,
137 ST_File,
138 ST_Function,
139 ST_Other
140 };
141
142 SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner);
143
144 std::error_code getName(StringRef &Result) const;
145 /// Returns the symbol virtual address (i.e. address at which it will be
146 /// mapped).
147 std::error_code getAddress(uint64_t &Result) const;
148 /// @brief Get the alignment of this symbol as the actual value (not log 2).
149 std::error_code getAlignment(uint32_t &Result) const;
150 std::error_code getSize(uint64_t &Result) const;
151 std::error_code getType(SymbolRef::Type &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
160 class symbol_iterator : public basic_symbol_iterator {
161 public:
symbol_iterator(SymbolRef Sym)162 symbol_iterator(SymbolRef Sym) : basic_symbol_iterator(Sym) {}
symbol_iterator(const basic_symbol_iterator & B)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 /// LibraryRef - This is a value type class that represents a single library in
179 /// the list of libraries needed by a shared or dynamic object.
180 class LibraryRef {
181 friend class SectionRef;
182 DataRefImpl LibraryPimpl;
183 const ObjectFile *OwningObject;
184
185 public:
LibraryRef()186 LibraryRef() : OwningObject(nullptr) { }
187
188 LibraryRef(DataRefImpl LibraryP, const ObjectFile *Owner);
189
190 bool operator==(const LibraryRef &Other) const;
191 bool operator<(const LibraryRef &Other) const;
192
193 std::error_code getNext(LibraryRef &Result) const;
194
195 // Get the path to this library, as stored in the object file.
196 std::error_code getPath(StringRef &Result) const;
197
198 DataRefImpl getRawDataRefImpl() const;
199 };
200 typedef content_iterator<LibraryRef> library_iterator;
201
202 /// ObjectFile - This class is the base class for all object file types.
203 /// Concrete instances of this object are created by createObjectFile, which
204 /// figures out which type to create.
205 class ObjectFile : public SymbolicFile {
206 virtual void anchor();
207 ObjectFile() LLVM_DELETED_FUNCTION;
208 ObjectFile(const ObjectFile &other) LLVM_DELETED_FUNCTION;
209
210 protected:
211 ObjectFile(unsigned int Type, std::unique_ptr<MemoryBuffer> Source);
212
base()213 const uint8_t *base() const {
214 return reinterpret_cast<const uint8_t *>(Data->getBufferStart());
215 }
216
217 // These functions are for SymbolRef to call internally. The main goal of
218 // this is to allow SymbolRef::SymbolPimpl to point directly to the symbol
219 // entry in the memory mapped object file. SymbolPimpl cannot contain any
220 // virtual functions because then it could not point into the memory mapped
221 // file.
222 //
223 // Implementations assume that the DataRefImpl is valid and has not been
224 // modified externally. It's UB otherwise.
225 friend class SymbolRef;
226 virtual std::error_code getSymbolName(DataRefImpl Symb,
227 StringRef &Res) const = 0;
228 std::error_code printSymbolName(raw_ostream &OS,
229 DataRefImpl Symb) const override;
230 virtual std::error_code getSymbolAddress(DataRefImpl Symb,
231 uint64_t &Res) const = 0;
232 virtual std::error_code getSymbolAlignment(DataRefImpl Symb,
233 uint32_t &Res) const;
234 virtual std::error_code getSymbolSize(DataRefImpl Symb,
235 uint64_t &Res) const = 0;
236 virtual std::error_code getSymbolType(DataRefImpl Symb,
237 SymbolRef::Type &Res) const = 0;
238 virtual std::error_code getSymbolSection(DataRefImpl Symb,
239 section_iterator &Res) const = 0;
240
241 // Same as above for SectionRef.
242 friend class SectionRef;
243 virtual void moveSectionNext(DataRefImpl &Sec) const = 0;
244 virtual std::error_code getSectionName(DataRefImpl Sec,
245 StringRef &Res) const = 0;
246 virtual std::error_code getSectionAddress(DataRefImpl Sec,
247 uint64_t &Res) const = 0;
248 virtual std::error_code getSectionSize(DataRefImpl Sec,
249 uint64_t &Res) const = 0;
250 virtual std::error_code getSectionContents(DataRefImpl Sec,
251 StringRef &Res) const = 0;
252 virtual std::error_code getSectionAlignment(DataRefImpl Sec,
253 uint64_t &Res) const = 0;
254 virtual std::error_code isSectionText(DataRefImpl Sec, bool &Res) const = 0;
255 virtual std::error_code isSectionData(DataRefImpl Sec, bool &Res) const = 0;
256 virtual std::error_code isSectionBSS(DataRefImpl Sec, bool &Res) const = 0;
257 virtual std::error_code isSectionRequiredForExecution(DataRefImpl Sec,
258 bool &Res) const = 0;
259 // A section is 'virtual' if its contents aren't present in the object image.
260 virtual std::error_code isSectionVirtual(DataRefImpl Sec,
261 bool &Res) const = 0;
262 virtual std::error_code isSectionZeroInit(DataRefImpl Sec,
263 bool &Res) const = 0;
264 virtual std::error_code isSectionReadOnlyData(DataRefImpl Sec,
265 bool &Res) const = 0;
266 virtual std::error_code sectionContainsSymbol(DataRefImpl Sec,
267 DataRefImpl Symb,
268 bool &Result) const = 0;
269 virtual relocation_iterator section_rel_begin(DataRefImpl Sec) const = 0;
270 virtual relocation_iterator section_rel_end(DataRefImpl Sec) const = 0;
271 virtual section_iterator getRelocatedSection(DataRefImpl Sec) const;
272
273 // Same as above for RelocationRef.
274 friend class RelocationRef;
275 virtual void moveRelocationNext(DataRefImpl &Rel) const = 0;
276 virtual std::error_code getRelocationAddress(DataRefImpl Rel,
277 uint64_t &Res) const = 0;
278 virtual std::error_code getRelocationOffset(DataRefImpl Rel,
279 uint64_t &Res) const = 0;
280 virtual symbol_iterator getRelocationSymbol(DataRefImpl Rel) const = 0;
281 virtual std::error_code getRelocationType(DataRefImpl Rel,
282 uint64_t &Res) const = 0;
283 virtual std::error_code
284 getRelocationTypeName(DataRefImpl Rel,
285 SmallVectorImpl<char> &Result) const = 0;
286 virtual std::error_code
287 getRelocationValueString(DataRefImpl Rel,
288 SmallVectorImpl<char> &Result) const = 0;
getRelocationHidden(DataRefImpl Rel,bool & Result)289 virtual std::error_code getRelocationHidden(DataRefImpl Rel,
290 bool &Result) const {
291 Result = false;
292 return object_error::success;
293 }
294
295 // Same for LibraryRef
296 friend class LibraryRef;
297 virtual std::error_code getLibraryNext(DataRefImpl Lib,
298 LibraryRef &Res) const = 0;
299 virtual std::error_code getLibraryPath(DataRefImpl Lib,
300 StringRef &Res) const = 0;
301
302 public:
303 typedef iterator_range<symbol_iterator> symbol_iterator_range;
symbols()304 symbol_iterator_range symbols() const {
305 return symbol_iterator_range(symbol_begin(), symbol_end());
306 }
307
308 virtual section_iterator section_begin() const = 0;
309 virtual section_iterator section_end() const = 0;
310
311 typedef iterator_range<section_iterator> section_iterator_range;
sections()312 section_iterator_range sections() const {
313 return section_iterator_range(section_begin(), section_end());
314 }
315
316 virtual library_iterator needed_library_begin() const = 0;
317 virtual library_iterator needed_library_end() const = 0;
318
319 /// @brief The number of bytes used to represent an address in this object
320 /// file format.
321 virtual uint8_t getBytesInAddress() const = 0;
322
323 virtual StringRef getFileFormatName() const = 0;
324 virtual /* Triple::ArchType */ unsigned getArch() const = 0;
325
326 /// For shared objects, returns the name which this object should be
327 /// loaded from at runtime. This corresponds to DT_SONAME on ELF and
328 /// LC_ID_DYLIB (install name) on MachO.
329 virtual StringRef getLoadName() const = 0;
330
331 /// @returns Pointer to ObjectFile subclass to handle this type of object.
332 /// @param ObjectPath The path to the object file. ObjectPath.isObject must
333 /// return true.
334 /// @brief Create ObjectFile from path.
335 static ErrorOr<ObjectFile *> createObjectFile(StringRef ObjectPath);
336 static ErrorOr<ObjectFile *>
337 createObjectFile(std::unique_ptr<MemoryBuffer> &Object,
338 sys::fs::file_magic Type);
339 static ErrorOr<ObjectFile *>
createObjectFile(std::unique_ptr<MemoryBuffer> & Object)340 createObjectFile(std::unique_ptr<MemoryBuffer> &Object) {
341 return createObjectFile(Object, sys::fs::file_magic::unknown);
342 }
343
344
classof(const Binary * v)345 static inline bool classof(const Binary *v) {
346 return v->isObject();
347 }
348
349 public:
350 static ErrorOr<ObjectFile *>
351 createCOFFObjectFile(std::unique_ptr<MemoryBuffer> Object);
352 static ErrorOr<ObjectFile *>
353 createELFObjectFile(std::unique_ptr<MemoryBuffer> &Object);
354 static ErrorOr<ObjectFile *>
355 createMachOObjectFile(std::unique_ptr<MemoryBuffer> &Object);
356 };
357
358 // Inline function definitions.
SymbolRef(DataRefImpl SymbolP,const ObjectFile * Owner)359 inline SymbolRef::SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner)
360 : BasicSymbolRef(SymbolP, Owner) {}
361
getName(StringRef & Result)362 inline std::error_code SymbolRef::getName(StringRef &Result) const {
363 return getObject()->getSymbolName(getRawDataRefImpl(), Result);
364 }
365
getAddress(uint64_t & Result)366 inline std::error_code SymbolRef::getAddress(uint64_t &Result) const {
367 return getObject()->getSymbolAddress(getRawDataRefImpl(), Result);
368 }
369
getAlignment(uint32_t & Result)370 inline std::error_code SymbolRef::getAlignment(uint32_t &Result) const {
371 return getObject()->getSymbolAlignment(getRawDataRefImpl(), Result);
372 }
373
getSize(uint64_t & Result)374 inline std::error_code SymbolRef::getSize(uint64_t &Result) const {
375 return getObject()->getSymbolSize(getRawDataRefImpl(), Result);
376 }
377
getSection(section_iterator & Result)378 inline std::error_code SymbolRef::getSection(section_iterator &Result) const {
379 return getObject()->getSymbolSection(getRawDataRefImpl(), Result);
380 }
381
getType(SymbolRef::Type & Result)382 inline std::error_code SymbolRef::getType(SymbolRef::Type &Result) const {
383 return getObject()->getSymbolType(getRawDataRefImpl(), Result);
384 }
385
getObject()386 inline const ObjectFile *SymbolRef::getObject() const {
387 const SymbolicFile *O = BasicSymbolRef::getObject();
388 return cast<ObjectFile>(O);
389 }
390
391
392 /// SectionRef
SectionRef(DataRefImpl SectionP,const ObjectFile * Owner)393 inline SectionRef::SectionRef(DataRefImpl SectionP,
394 const ObjectFile *Owner)
395 : SectionPimpl(SectionP)
396 , OwningObject(Owner) {}
397
398 inline bool SectionRef::operator==(const SectionRef &Other) const {
399 return SectionPimpl == Other.SectionPimpl;
400 }
401
402 inline bool SectionRef::operator!=(const SectionRef &Other) const {
403 return SectionPimpl != Other.SectionPimpl;
404 }
405
406 inline bool SectionRef::operator<(const SectionRef &Other) const {
407 return SectionPimpl < Other.SectionPimpl;
408 }
409
moveNext()410 inline void SectionRef::moveNext() {
411 return OwningObject->moveSectionNext(SectionPimpl);
412 }
413
getName(StringRef & Result)414 inline std::error_code SectionRef::getName(StringRef &Result) const {
415 return OwningObject->getSectionName(SectionPimpl, Result);
416 }
417
getAddress(uint64_t & Result)418 inline std::error_code SectionRef::getAddress(uint64_t &Result) const {
419 return OwningObject->getSectionAddress(SectionPimpl, Result);
420 }
421
getSize(uint64_t & Result)422 inline std::error_code SectionRef::getSize(uint64_t &Result) const {
423 return OwningObject->getSectionSize(SectionPimpl, Result);
424 }
425
getContents(StringRef & Result)426 inline std::error_code SectionRef::getContents(StringRef &Result) const {
427 return OwningObject->getSectionContents(SectionPimpl, Result);
428 }
429
getAlignment(uint64_t & Result)430 inline std::error_code SectionRef::getAlignment(uint64_t &Result) const {
431 return OwningObject->getSectionAlignment(SectionPimpl, Result);
432 }
433
isText(bool & Result)434 inline std::error_code SectionRef::isText(bool &Result) const {
435 return OwningObject->isSectionText(SectionPimpl, Result);
436 }
437
isData(bool & Result)438 inline std::error_code SectionRef::isData(bool &Result) const {
439 return OwningObject->isSectionData(SectionPimpl, Result);
440 }
441
isBSS(bool & Result)442 inline std::error_code SectionRef::isBSS(bool &Result) const {
443 return OwningObject->isSectionBSS(SectionPimpl, Result);
444 }
445
isRequiredForExecution(bool & Result)446 inline std::error_code SectionRef::isRequiredForExecution(bool &Result) const {
447 return OwningObject->isSectionRequiredForExecution(SectionPimpl, Result);
448 }
449
isVirtual(bool & Result)450 inline std::error_code SectionRef::isVirtual(bool &Result) const {
451 return OwningObject->isSectionVirtual(SectionPimpl, Result);
452 }
453
isZeroInit(bool & Result)454 inline std::error_code SectionRef::isZeroInit(bool &Result) const {
455 return OwningObject->isSectionZeroInit(SectionPimpl, Result);
456 }
457
isReadOnlyData(bool & Result)458 inline std::error_code SectionRef::isReadOnlyData(bool &Result) const {
459 return OwningObject->isSectionReadOnlyData(SectionPimpl, Result);
460 }
461
containsSymbol(SymbolRef S,bool & Result)462 inline std::error_code SectionRef::containsSymbol(SymbolRef S,
463 bool &Result) const {
464 return OwningObject->sectionContainsSymbol(SectionPimpl,
465 S.getRawDataRefImpl(), Result);
466 }
467
relocation_begin()468 inline relocation_iterator SectionRef::relocation_begin() const {
469 return OwningObject->section_rel_begin(SectionPimpl);
470 }
471
relocation_end()472 inline relocation_iterator SectionRef::relocation_end() const {
473 return OwningObject->section_rel_end(SectionPimpl);
474 }
475
getRelocatedSection()476 inline section_iterator SectionRef::getRelocatedSection() const {
477 return OwningObject->getRelocatedSection(SectionPimpl);
478 }
479
getRawDataRefImpl()480 inline DataRefImpl SectionRef::getRawDataRefImpl() const {
481 return SectionPimpl;
482 }
483
484 /// RelocationRef
RelocationRef(DataRefImpl RelocationP,const ObjectFile * Owner)485 inline RelocationRef::RelocationRef(DataRefImpl RelocationP,
486 const ObjectFile *Owner)
487 : RelocationPimpl(RelocationP)
488 , OwningObject(Owner) {}
489
490 inline bool RelocationRef::operator==(const RelocationRef &Other) const {
491 return RelocationPimpl == Other.RelocationPimpl;
492 }
493
moveNext()494 inline void RelocationRef::moveNext() {
495 return OwningObject->moveRelocationNext(RelocationPimpl);
496 }
497
getAddress(uint64_t & Result)498 inline std::error_code RelocationRef::getAddress(uint64_t &Result) const {
499 return OwningObject->getRelocationAddress(RelocationPimpl, Result);
500 }
501
getOffset(uint64_t & Result)502 inline std::error_code RelocationRef::getOffset(uint64_t &Result) const {
503 return OwningObject->getRelocationOffset(RelocationPimpl, Result);
504 }
505
getSymbol()506 inline symbol_iterator RelocationRef::getSymbol() const {
507 return OwningObject->getRelocationSymbol(RelocationPimpl);
508 }
509
getType(uint64_t & Result)510 inline std::error_code RelocationRef::getType(uint64_t &Result) const {
511 return OwningObject->getRelocationType(RelocationPimpl, Result);
512 }
513
514 inline std::error_code
getTypeName(SmallVectorImpl<char> & Result)515 RelocationRef::getTypeName(SmallVectorImpl<char> &Result) const {
516 return OwningObject->getRelocationTypeName(RelocationPimpl, Result);
517 }
518
519 inline std::error_code
getValueString(SmallVectorImpl<char> & Result)520 RelocationRef::getValueString(SmallVectorImpl<char> &Result) const {
521 return OwningObject->getRelocationValueString(RelocationPimpl, Result);
522 }
523
getHidden(bool & Result)524 inline std::error_code RelocationRef::getHidden(bool &Result) const {
525 return OwningObject->getRelocationHidden(RelocationPimpl, Result);
526 }
527
getRawDataRefImpl()528 inline DataRefImpl RelocationRef::getRawDataRefImpl() const {
529 return RelocationPimpl;
530 }
531
getObjectFile()532 inline const ObjectFile *RelocationRef::getObjectFile() const {
533 return OwningObject;
534 }
535
536 // Inline function definitions.
LibraryRef(DataRefImpl LibraryP,const ObjectFile * Owner)537 inline LibraryRef::LibraryRef(DataRefImpl LibraryP, const ObjectFile *Owner)
538 : LibraryPimpl(LibraryP)
539 , OwningObject(Owner) {}
540
541 inline bool LibraryRef::operator==(const LibraryRef &Other) const {
542 return LibraryPimpl == Other.LibraryPimpl;
543 }
544
545 inline bool LibraryRef::operator<(const LibraryRef &Other) const {
546 return LibraryPimpl < Other.LibraryPimpl;
547 }
548
getNext(LibraryRef & Result)549 inline std::error_code LibraryRef::getNext(LibraryRef &Result) const {
550 return OwningObject->getLibraryNext(LibraryPimpl, Result);
551 }
552
getPath(StringRef & Result)553 inline std::error_code LibraryRef::getPath(StringRef &Result) const {
554 return OwningObject->getLibraryPath(LibraryPimpl, Result);
555 }
556
557 } // end namespace object
558 } // end namespace llvm
559
560 #endif
561