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 class COFFObjectFile;
31 class MachOObjectFile;
32
33 class SymbolRef;
34 class 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.
38 class RelocationRef {
39 DataRefImpl RelocationPimpl;
40 const ObjectFile *OwningObject;
41
42 public:
RelocationRef()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 };
75 typedef 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.
79 class SectionRef;
80 typedef content_iterator<SectionRef> section_iterator;
81 class SectionRef {
82 friend class SymbolRef;
83 DataRefImpl SectionPimpl;
84 const ObjectFile *OwningObject;
85
86 public:
SectionRef()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;
relocations()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.
126 class SymbolRef : public BasicSymbolRef {
127 friend class SectionRef;
128
129 public:
SymbolRef()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
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 /// 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.
181 class ObjectFile : public SymbolicFile {
182 virtual void anchor();
183 ObjectFile() = delete;
184 ObjectFile(const ObjectFile &other) = delete;
185
186 protected:
187 ObjectFile(unsigned int Type, MemoryBufferRef Source);
188
base()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;
getSymbolOther(DataRefImpl Symb,uint8_t & Res)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;
getRelocationHidden(DataRefImpl Rel,bool & Result)258 virtual std::error_code getRelocationHidden(DataRefImpl Rel,
259 bool &Result) const {
260 Result = false;
261 return object_error::success;
262 }
263
264 public:
265 typedef iterator_range<symbol_iterator> symbol_iterator_range;
symbols()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;
sections()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.
getPlatformFlags(unsigned & Result)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>>
createObjectFile(MemoryBufferRef Object)304 createObjectFile(MemoryBufferRef Object) {
305 return createObjectFile(Object, sys::fs::file_magic::unknown);
306 }
307
308
classof(const Binary * v)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.
SymbolRef(DataRefImpl SymbolP,const ObjectFile * Owner)324 inline SymbolRef::SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner)
325 : BasicSymbolRef(SymbolP, Owner) {}
326
getName(StringRef & Result)327 inline std::error_code SymbolRef::getName(StringRef &Result) const {
328 return getObject()->getSymbolName(getRawDataRefImpl(), Result);
329 }
330
getAddress(uint64_t & Result)331 inline std::error_code SymbolRef::getAddress(uint64_t &Result) const {
332 return getObject()->getSymbolAddress(getRawDataRefImpl(), Result);
333 }
334
getAlignment(uint32_t & Result)335 inline std::error_code SymbolRef::getAlignment(uint32_t &Result) const {
336 return getObject()->getSymbolAlignment(getRawDataRefImpl(), Result);
337 }
338
getSize(uint64_t & Result)339 inline std::error_code SymbolRef::getSize(uint64_t &Result) const {
340 return getObject()->getSymbolSize(getRawDataRefImpl(), Result);
341 }
342
getSection(section_iterator & Result)343 inline std::error_code SymbolRef::getSection(section_iterator &Result) const {
344 return getObject()->getSymbolSection(getRawDataRefImpl(), Result);
345 }
346
getType(SymbolRef::Type & Result)347 inline std::error_code SymbolRef::getType(SymbolRef::Type &Result) const {
348 return getObject()->getSymbolType(getRawDataRefImpl(), Result);
349 }
350
getOther(uint8_t & Result)351 inline std::error_code SymbolRef::getOther(uint8_t &Result) const {
352 return getObject()->getSymbolOther(getRawDataRefImpl(), Result);
353 }
354
getObject()355 inline const ObjectFile *SymbolRef::getObject() const {
356 const SymbolicFile *O = BasicSymbolRef::getObject();
357 return cast<ObjectFile>(O);
358 }
359
360
361 /// SectionRef
SectionRef(DataRefImpl SectionP,const ObjectFile * Owner)362 inline SectionRef::SectionRef(DataRefImpl SectionP,
363 const ObjectFile *Owner)
364 : SectionPimpl(SectionP)
365 , OwningObject(Owner) {}
366
367 inline bool SectionRef::operator==(const SectionRef &Other) const {
368 return SectionPimpl == Other.SectionPimpl;
369 }
370
371 inline bool SectionRef::operator!=(const SectionRef &Other) const {
372 return SectionPimpl != Other.SectionPimpl;
373 }
374
375 inline bool SectionRef::operator<(const SectionRef &Other) const {
376 return SectionPimpl < Other.SectionPimpl;
377 }
378
moveNext()379 inline void SectionRef::moveNext() {
380 return OwningObject->moveSectionNext(SectionPimpl);
381 }
382
getName(StringRef & Result)383 inline std::error_code SectionRef::getName(StringRef &Result) const {
384 return OwningObject->getSectionName(SectionPimpl, Result);
385 }
386
getAddress()387 inline uint64_t SectionRef::getAddress() const {
388 return OwningObject->getSectionAddress(SectionPimpl);
389 }
390
getSize()391 inline uint64_t SectionRef::getSize() const {
392 return OwningObject->getSectionSize(SectionPimpl);
393 }
394
getContents(StringRef & Result)395 inline std::error_code SectionRef::getContents(StringRef &Result) const {
396 return OwningObject->getSectionContents(SectionPimpl, Result);
397 }
398
getAlignment()399 inline uint64_t SectionRef::getAlignment() const {
400 return OwningObject->getSectionAlignment(SectionPimpl);
401 }
402
isText()403 inline bool SectionRef::isText() const {
404 return OwningObject->isSectionText(SectionPimpl);
405 }
406
isData()407 inline bool SectionRef::isData() const {
408 return OwningObject->isSectionData(SectionPimpl);
409 }
410
isBSS()411 inline bool SectionRef::isBSS() const {
412 return OwningObject->isSectionBSS(SectionPimpl);
413 }
414
isVirtual()415 inline bool SectionRef::isVirtual() const {
416 return OwningObject->isSectionVirtual(SectionPimpl);
417 }
418
containsSymbol(SymbolRef S)419 inline bool SectionRef::containsSymbol(SymbolRef S) const {
420 return OwningObject->sectionContainsSymbol(SectionPimpl,
421 S.getRawDataRefImpl());
422 }
423
relocation_begin()424 inline relocation_iterator SectionRef::relocation_begin() const {
425 return OwningObject->section_rel_begin(SectionPimpl);
426 }
427
relocation_end()428 inline relocation_iterator SectionRef::relocation_end() const {
429 return OwningObject->section_rel_end(SectionPimpl);
430 }
431
getRelocatedSection()432 inline section_iterator SectionRef::getRelocatedSection() const {
433 return OwningObject->getRelocatedSection(SectionPimpl);
434 }
435
getRawDataRefImpl()436 inline DataRefImpl SectionRef::getRawDataRefImpl() const {
437 return SectionPimpl;
438 }
439
getObject()440 inline const ObjectFile *SectionRef::getObject() const {
441 return OwningObject;
442 }
443
444 /// RelocationRef
RelocationRef(DataRefImpl RelocationP,const ObjectFile * Owner)445 inline RelocationRef::RelocationRef(DataRefImpl RelocationP,
446 const ObjectFile *Owner)
447 : RelocationPimpl(RelocationP)
448 , OwningObject(Owner) {}
449
450 inline bool RelocationRef::operator==(const RelocationRef &Other) const {
451 return RelocationPimpl == Other.RelocationPimpl;
452 }
453
moveNext()454 inline void RelocationRef::moveNext() {
455 return OwningObject->moveRelocationNext(RelocationPimpl);
456 }
457
getAddress(uint64_t & Result)458 inline std::error_code RelocationRef::getAddress(uint64_t &Result) const {
459 return OwningObject->getRelocationAddress(RelocationPimpl, Result);
460 }
461
getOffset(uint64_t & Result)462 inline std::error_code RelocationRef::getOffset(uint64_t &Result) const {
463 return OwningObject->getRelocationOffset(RelocationPimpl, Result);
464 }
465
getSymbol()466 inline symbol_iterator RelocationRef::getSymbol() const {
467 return OwningObject->getRelocationSymbol(RelocationPimpl);
468 }
469
getType(uint64_t & Result)470 inline std::error_code RelocationRef::getType(uint64_t &Result) const {
471 return OwningObject->getRelocationType(RelocationPimpl, Result);
472 }
473
474 inline std::error_code
getTypeName(SmallVectorImpl<char> & Result)475 RelocationRef::getTypeName(SmallVectorImpl<char> &Result) const {
476 return OwningObject->getRelocationTypeName(RelocationPimpl, Result);
477 }
478
479 inline std::error_code
getValueString(SmallVectorImpl<char> & Result)480 RelocationRef::getValueString(SmallVectorImpl<char> &Result) const {
481 return OwningObject->getRelocationValueString(RelocationPimpl, Result);
482 }
483
getHidden(bool & Result)484 inline std::error_code RelocationRef::getHidden(bool &Result) const {
485 return OwningObject->getRelocationHidden(RelocationPimpl, Result);
486 }
487
getRawDataRefImpl()488 inline DataRefImpl RelocationRef::getRawDataRefImpl() const {
489 return RelocationPimpl;
490 }
491
getObjectFile()492 inline const ObjectFile *RelocationRef::getObjectFile() const {
493 return OwningObject;
494 }
495
496
497 } // end namespace object
498 } // end namespace llvm
499
500 #endif
501