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