ObjectFile.h revision e2f2f07be7cf2b55b7e5501291bbcede87e43fd6
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_OBJECT_FILE_H 15#define LLVM_OBJECT_OBJECT_FILE_H 16 17#include "llvm/Object/Binary.h" 18#include "llvm/ADT/StringRef.h" 19#include "llvm/Support/DataTypes.h" 20#include "llvm/Support/ErrorHandling.h" 21#include "llvm/Support/MemoryBuffer.h" 22#include <cstring> 23 24namespace llvm { 25namespace object { 26 27class ObjectFile; 28 29union DataRefImpl { 30 struct { 31 // ELF needs this for relocations. This entire union should probably be a 32 // char[max(8, sizeof(uintptr_t))] and require the impl to cast. 33 uint16_t a, b; 34 uint32_t c; 35 } w; 36 struct { 37 uint32_t a, b; 38 } d; 39 uintptr_t p; 40}; 41 42template<class content_type> 43class content_iterator { 44 content_type Current; 45public: 46 content_iterator(content_type symb) 47 : Current(symb) {} 48 49 const content_type* operator->() const { 50 return &Current; 51 } 52 53 const content_type &operator*() const { 54 return Current; 55 } 56 57 bool operator==(const content_iterator &other) const { 58 return Current == other.Current; 59 } 60 61 bool operator!=(const content_iterator &other) const { 62 return !(*this == other); 63 } 64 65 content_iterator& increment(error_code &err) { 66 content_type next; 67 if (error_code ec = Current.getNext(next)) 68 err = ec; 69 else 70 Current = next; 71 return *this; 72 } 73}; 74 75static bool operator ==(const DataRefImpl &a, const DataRefImpl &b) { 76 // Check bitwise identical. This is the only legal way to compare a union w/o 77 // knowing which member is in use. 78 return std::memcmp(&a, &b, sizeof(DataRefImpl)) == 0; 79} 80 81/// SymbolRef - This is a value type class that represents a single symbol in 82/// the list of symbols in the object file. 83class SymbolRef { 84 friend class SectionRef; 85 DataRefImpl SymbolPimpl; 86 const ObjectFile *OwningObject; 87 88public: 89 SymbolRef() : OwningObject(NULL) { 90 std::memset(&SymbolPimpl, 0, sizeof(SymbolPimpl)); 91 } 92 93 enum SymbolType { 94 ST_Function, 95 ST_Data, 96 ST_External, // Defined in another object file 97 ST_Other 98 }; 99 100 SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner); 101 102 bool operator==(const SymbolRef &Other) const; 103 104 error_code getNext(SymbolRef &Result) const; 105 106 error_code getName(StringRef &Result) const; 107 error_code getAddress(uint64_t &Result) const; 108 error_code getOffset(uint64_t &Result) const; 109 error_code getSize(uint64_t &Result) const; 110 error_code getSymbolType(SymbolRef::SymbolType &Result) const; 111 112 /// Returns the ascii char that should be displayed in a symbol table dump via 113 /// nm for this symbol. 114 error_code getNMTypeChar(char &Result) const; 115 116 /// Returns true for symbols that are internal to the object file format such 117 /// as section symbols. 118 error_code isInternal(bool &Result) const; 119 120 /// Returns true for symbols that can be used in another objects, 121 /// such as library functions 122 error_code isGlobal(bool &Result) const; 123}; 124typedef content_iterator<SymbolRef> symbol_iterator; 125 126/// RelocationRef - This is a value type class that represents a single 127/// relocation in the list of relocations in the object file. 128class RelocationRef { 129 DataRefImpl RelocationPimpl; 130 const ObjectFile *OwningObject; 131 132public: 133 RelocationRef() : OwningObject(NULL) { 134 std::memset(&RelocationPimpl, 0, sizeof(RelocationPimpl)); 135 } 136 137 RelocationRef(DataRefImpl RelocationP, const ObjectFile *Owner); 138 139 bool operator==(const RelocationRef &Other) const; 140 141 error_code getNext(RelocationRef &Result) const; 142 143 error_code getAddress(uint64_t &Result) const; 144 error_code getSymbol(SymbolRef &Result) const; 145 error_code getType(uint32_t &Result) const; 146 147 /// @brief Get a string that represents the type of this relocation. 148 /// 149 /// This is for display purposes only. 150 error_code getTypeName(SmallVectorImpl<char> &Result) const; 151 error_code getAdditionalInfo(int64_t &Result) const; 152 153 /// @brief Get a string that represents the calculation of the value of this 154 /// relocation. 155 /// 156 /// This is for display purposes only. 157 error_code getValueString(SmallVectorImpl<char> &Result) const; 158}; 159typedef content_iterator<RelocationRef> relocation_iterator; 160 161/// SectionRef - This is a value type class that represents a single section in 162/// the list of sections in the object file. 163class SectionRef { 164 friend class SymbolRef; 165 DataRefImpl SectionPimpl; 166 const ObjectFile *OwningObject; 167 168public: 169 SectionRef() : OwningObject(NULL) { 170 std::memset(&SectionPimpl, 0, sizeof(SectionPimpl)); 171 } 172 173 SectionRef(DataRefImpl SectionP, const ObjectFile *Owner); 174 175 bool operator==(const SectionRef &Other) const; 176 177 error_code getNext(SectionRef &Result) const; 178 179 error_code getName(StringRef &Result) const; 180 error_code getAddress(uint64_t &Result) const; 181 error_code getSize(uint64_t &Result) const; 182 error_code getContents(StringRef &Result) const; 183 184 /// @brief Get the alignment of this section as the actual value (not log 2). 185 error_code getAlignment(uint64_t &Result) const; 186 187 // FIXME: Move to the normalization layer when it's created. 188 error_code isText(bool &Result) const; 189 error_code isData(bool &Result) const; 190 error_code isBSS(bool &Result) const; 191 192 error_code containsSymbol(SymbolRef S, bool &Result) const; 193 194 relocation_iterator begin_relocations() const; 195 relocation_iterator end_relocations() const; 196}; 197typedef content_iterator<SectionRef> section_iterator; 198 199const uint64_t UnknownAddressOrSize = ~0ULL; 200 201/// ObjectFile - This class is the base class for all object file types. 202/// Concrete instances of this object are created by createObjectFile, which 203/// figure out which type to create. 204class ObjectFile : public Binary { 205private: 206 ObjectFile(); // = delete 207 ObjectFile(const ObjectFile &other); // = delete 208 209protected: 210 ObjectFile(unsigned int Type, MemoryBuffer *source, error_code &ec); 211 212 const uint8_t *base() const { 213 return reinterpret_cast<const uint8_t *>(Data->getBufferStart()); 214 } 215 216 // These functions are for SymbolRef to call internally. The main goal of 217 // this is to allow SymbolRef::SymbolPimpl to point directly to the symbol 218 // entry in the memory mapped object file. SymbolPimpl cannot contain any 219 // virtual functions because then it could not point into the memory mapped 220 // file. 221 // 222 // Implementations assume that the DataRefImpl is valid and has not been 223 // modified externally. It's UB otherwise. 224 friend class SymbolRef; 225 virtual error_code getSymbolNext(DataRefImpl Symb, SymbolRef &Res) const = 0; 226 virtual error_code getSymbolName(DataRefImpl Symb, StringRef &Res) const = 0; 227 virtual error_code getSymbolAddress(DataRefImpl Symb, uint64_t &Res) const =0; 228 virtual error_code getSymbolOffset(DataRefImpl Symb, uint64_t &Res) const =0; 229 virtual error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const = 0; 230 virtual error_code getSymbolNMTypeChar(DataRefImpl Symb, char &Res) const = 0; 231 virtual error_code isSymbolInternal(DataRefImpl Symb, bool &Res) const = 0; 232 virtual error_code isSymbolGlobal(DataRefImpl Symb, bool &Res) const = 0; 233 virtual error_code getSymbolType(DataRefImpl Symb, SymbolRef::SymbolType &Res) const = 0; 234 235 // Same as above for SectionRef. 236 friend class SectionRef; 237 virtual error_code getSectionNext(DataRefImpl Sec, SectionRef &Res) const = 0; 238 virtual error_code getSectionName(DataRefImpl Sec, StringRef &Res) const = 0; 239 virtual error_code getSectionAddress(DataRefImpl Sec, uint64_t &Res) const =0; 240 virtual error_code getSectionSize(DataRefImpl Sec, uint64_t &Res) const = 0; 241 virtual error_code getSectionContents(DataRefImpl Sec, StringRef &Res)const=0; 242 virtual error_code getSectionAlignment(DataRefImpl Sec, uint64_t &Res)const=0; 243 virtual error_code isSectionText(DataRefImpl Sec, bool &Res) const = 0; 244 virtual error_code isSectionData(DataRefImpl Sec, bool &Res) const = 0; 245 virtual error_code isSectionBSS(DataRefImpl Sec, bool &Res) const = 0; 246 virtual error_code sectionContainsSymbol(DataRefImpl Sec, DataRefImpl Symb, 247 bool &Result) const = 0; 248 virtual relocation_iterator getSectionRelBegin(DataRefImpl Sec) const = 0; 249 virtual relocation_iterator getSectionRelEnd(DataRefImpl Sec) const = 0; 250 251 252 // Same as above for RelocationRef. 253 friend class RelocationRef; 254 virtual error_code getRelocationNext(DataRefImpl Rel, 255 RelocationRef &Res) const = 0; 256 virtual error_code getRelocationAddress(DataRefImpl Rel, 257 uint64_t &Res) const =0; 258 virtual error_code getRelocationSymbol(DataRefImpl Rel, 259 SymbolRef &Res) const = 0; 260 virtual error_code getRelocationType(DataRefImpl Rel, 261 uint32_t &Res) const = 0; 262 virtual error_code getRelocationTypeName(DataRefImpl Rel, 263 SmallVectorImpl<char> &Result) const = 0; 264 virtual error_code getRelocationAdditionalInfo(DataRefImpl Rel, 265 int64_t &Res) const = 0; 266 virtual error_code getRelocationValueString(DataRefImpl Rel, 267 SmallVectorImpl<char> &Result) const = 0; 268 269public: 270 271 virtual symbol_iterator begin_symbols() const = 0; 272 virtual symbol_iterator end_symbols() const = 0; 273 274 virtual section_iterator begin_sections() const = 0; 275 virtual section_iterator end_sections() const = 0; 276 277 /// @brief The number of bytes used to represent an address in this object 278 /// file format. 279 virtual uint8_t getBytesInAddress() const = 0; 280 281 virtual StringRef getFileFormatName() const = 0; 282 virtual /* Triple::ArchType */ unsigned getArch() const = 0; 283 284 /// @returns Pointer to ObjectFile subclass to handle this type of object. 285 /// @param ObjectPath The path to the object file. ObjectPath.isObject must 286 /// return true. 287 /// @brief Create ObjectFile from path. 288 static ObjectFile *createObjectFile(StringRef ObjectPath); 289 static ObjectFile *createObjectFile(MemoryBuffer *Object); 290 291 static inline bool classof(const Binary *v) { 292 return v->getType() >= isObject && 293 v->getType() < lastObject; 294 } 295 static inline bool classof(const ObjectFile *v) { return true; } 296 297public: 298 static ObjectFile *createCOFFObjectFile(MemoryBuffer *Object); 299 static ObjectFile *createELFObjectFile(MemoryBuffer *Object); 300 static ObjectFile *createMachOObjectFile(MemoryBuffer *Object); 301}; 302 303// Inline function definitions. 304inline SymbolRef::SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner) 305 : SymbolPimpl(SymbolP) 306 , OwningObject(Owner) {} 307 308inline bool SymbolRef::operator==(const SymbolRef &Other) const { 309 return SymbolPimpl == Other.SymbolPimpl; 310} 311 312inline error_code SymbolRef::getNext(SymbolRef &Result) const { 313 return OwningObject->getSymbolNext(SymbolPimpl, Result); 314} 315 316inline error_code SymbolRef::getName(StringRef &Result) const { 317 return OwningObject->getSymbolName(SymbolPimpl, Result); 318} 319 320inline error_code SymbolRef::getAddress(uint64_t &Result) const { 321 return OwningObject->getSymbolAddress(SymbolPimpl, Result); 322} 323 324inline error_code SymbolRef::getOffset(uint64_t &Result) const { 325 return OwningObject->getSymbolOffset(SymbolPimpl, Result); 326} 327 328inline error_code SymbolRef::getSize(uint64_t &Result) const { 329 return OwningObject->getSymbolSize(SymbolPimpl, Result); 330} 331 332inline error_code SymbolRef::getNMTypeChar(char &Result) const { 333 return OwningObject->getSymbolNMTypeChar(SymbolPimpl, Result); 334} 335 336inline error_code SymbolRef::isInternal(bool &Result) const { 337 return OwningObject->isSymbolInternal(SymbolPimpl, Result); 338} 339 340inline error_code SymbolRef::isGlobal(bool &Result) const { 341 return OwningObject->isSymbolGlobal(SymbolPimpl, Result); 342} 343 344inline error_code SymbolRef::getSymbolType(SymbolRef::SymbolType &Result) const { 345 return OwningObject->getSymbolType(SymbolPimpl, Result); 346} 347 348 349/// SectionRef 350inline SectionRef::SectionRef(DataRefImpl SectionP, 351 const ObjectFile *Owner) 352 : SectionPimpl(SectionP) 353 , OwningObject(Owner) {} 354 355inline bool SectionRef::operator==(const SectionRef &Other) const { 356 return SectionPimpl == Other.SectionPimpl; 357} 358 359inline error_code SectionRef::getNext(SectionRef &Result) const { 360 return OwningObject->getSectionNext(SectionPimpl, Result); 361} 362 363inline error_code SectionRef::getName(StringRef &Result) const { 364 return OwningObject->getSectionName(SectionPimpl, Result); 365} 366 367inline error_code SectionRef::getAddress(uint64_t &Result) const { 368 return OwningObject->getSectionAddress(SectionPimpl, Result); 369} 370 371inline error_code SectionRef::getSize(uint64_t &Result) const { 372 return OwningObject->getSectionSize(SectionPimpl, Result); 373} 374 375inline error_code SectionRef::getContents(StringRef &Result) const { 376 return OwningObject->getSectionContents(SectionPimpl, Result); 377} 378 379inline error_code SectionRef::getAlignment(uint64_t &Result) const { 380 return OwningObject->getSectionAlignment(SectionPimpl, Result); 381} 382 383inline error_code SectionRef::isText(bool &Result) const { 384 return OwningObject->isSectionText(SectionPimpl, Result); 385} 386 387inline error_code SectionRef::isData(bool &Result) const { 388 return OwningObject->isSectionData(SectionPimpl, Result); 389} 390 391inline error_code SectionRef::isBSS(bool &Result) const { 392 return OwningObject->isSectionBSS(SectionPimpl, Result); 393} 394 395inline error_code SectionRef::containsSymbol(SymbolRef S, bool &Result) const { 396 return OwningObject->sectionContainsSymbol(SectionPimpl, S.SymbolPimpl, 397 Result); 398} 399 400inline relocation_iterator SectionRef::begin_relocations() const { 401 return OwningObject->getSectionRelBegin(SectionPimpl); 402} 403 404inline relocation_iterator SectionRef::end_relocations() const { 405 return OwningObject->getSectionRelEnd(SectionPimpl); 406} 407 408 409/// RelocationRef 410inline RelocationRef::RelocationRef(DataRefImpl RelocationP, 411 const ObjectFile *Owner) 412 : RelocationPimpl(RelocationP) 413 , OwningObject(Owner) {} 414 415inline bool RelocationRef::operator==(const RelocationRef &Other) const { 416 return RelocationPimpl == Other.RelocationPimpl; 417} 418 419inline error_code RelocationRef::getNext(RelocationRef &Result) const { 420 return OwningObject->getRelocationNext(RelocationPimpl, Result); 421} 422 423inline error_code RelocationRef::getAddress(uint64_t &Result) const { 424 return OwningObject->getRelocationAddress(RelocationPimpl, Result); 425} 426 427inline error_code RelocationRef::getSymbol(SymbolRef &Result) const { 428 return OwningObject->getRelocationSymbol(RelocationPimpl, Result); 429} 430 431inline error_code RelocationRef::getType(uint32_t &Result) const { 432 return OwningObject->getRelocationType(RelocationPimpl, Result); 433} 434 435inline error_code RelocationRef::getTypeName(SmallVectorImpl<char> &Result) 436 const { 437 return OwningObject->getRelocationTypeName(RelocationPimpl, Result); 438} 439 440inline error_code RelocationRef::getAdditionalInfo(int64_t &Result) const { 441 return OwningObject->getRelocationAdditionalInfo(RelocationPimpl, Result); 442} 443 444inline error_code RelocationRef::getValueString(SmallVectorImpl<char> &Result) 445 const { 446 return OwningObject->getRelocationValueString(RelocationPimpl, Result); 447} 448 449} // end namespace object 450} // end namespace llvm 451 452#endif 453