1 //===-- ObjectFile.h --------------------------------------------*- 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 #ifndef liblldb_ObjectFile_h_ 11 #define liblldb_ObjectFile_h_ 12 13 #include "lldb/lldb-private.h" 14 #include "lldb/Core/DataExtractor.h" 15 #include "lldb/Host/FileSpec.h" 16 #include "lldb/Core/FileSpecList.h" 17 #include "lldb/Core/ModuleChild.h" 18 #include "lldb/Core/PluginInterface.h" 19 #include "lldb/Host/Endian.h" 20 #include "lldb/Symbol/Symtab.h" 21 #include "lldb/Symbol/UnwindTable.h" 22 23 namespace lldb_private { 24 25 //---------------------------------------------------------------------- 26 /// @class ObjectFile ObjectFile.h "lldb/Symbol/ObjectFile.h" 27 /// @brief A plug-in interface definition class for object file parsers. 28 /// 29 /// Object files belong to Module objects and know how to extract 30 /// information from executable, shared library, and object (.o) files 31 /// used by operating system runtime. The symbol table and section list 32 /// for an object file. 33 /// 34 /// Object files can be represented by the entire file, or by part of a 35 /// file. Examples of object files that are part of a file include 36 /// object files that contain information for multiple architectures in 37 /// the same file, or archive files that contain multiple objects 38 /// (ranlib archives) (possibly for multiple architectures as well). 39 /// 40 /// Object archive files (e.g. ranlib archives) can contain 41 /// multiple .o (object) files that must be selected by index or by name. 42 /// The number of objects that an ObjectFile contains can be determined 43 /// using the ObjectFile::GetNumObjects() const 44 /// function, and followed by a call to 45 /// ObjectFile::SelectObjectAtIndex (uint32_t) to change the currently 46 /// selected object. Objects can also be selected by name using the 47 /// ObjectFile::SelectObject(const char *) function. 48 /// 49 /// Once an architecture is selected (and an object is selected for 50 /// for archives), the object file information can be extracted from 51 /// this abstract class. 52 //---------------------------------------------------------------------- 53 class ObjectFile: 54 public std::enable_shared_from_this<ObjectFile>, 55 public PluginInterface, 56 public ModuleChild 57 { 58 friend class lldb_private::Module; 59 60 public: 61 typedef enum 62 { 63 eTypeInvalid = 0, 64 eTypeCoreFile, /// A core file that has a checkpoint of a program's execution state 65 eTypeExecutable, /// A normal executable 66 eTypeDebugInfo, /// An object file that contains only debug information 67 eTypeDynamicLinker, /// The platform's dynamic linker executable 68 eTypeObjectFile, /// An intermediate object file 69 eTypeSharedLibrary, /// A shared library that can be used during execution 70 eTypeStubLibrary, /// A library that can be linked against but not used for execution 71 eTypeUnknown 72 } Type; 73 74 typedef enum 75 { 76 eStrataInvalid = 0, 77 eStrataUnknown, 78 eStrataUser, 79 eStrataKernel, 80 eStrataRawImage 81 } Strata; 82 83 //------------------------------------------------------------------ 84 /// Construct with a parent module, offset, and header data. 85 /// 86 /// Object files belong to modules and a valid module must be 87 /// supplied upon construction. The at an offset within a file for 88 /// objects that contain more than one architecture or object. 89 //------------------------------------------------------------------ 90 ObjectFile (const lldb::ModuleSP &module_sp, 91 const FileSpec *file_spec_ptr, 92 lldb::offset_t file_offset, 93 lldb::offset_t length, 94 lldb::DataBufferSP& data_sp, 95 lldb::offset_t data_offset); 96 97 ObjectFile (const lldb::ModuleSP &module_sp, 98 const lldb::ProcessSP &process_sp, 99 lldb::addr_t header_addr, 100 lldb::DataBufferSP& data_sp); 101 102 //------------------------------------------------------------------ 103 /// Destructor. 104 /// 105 /// The destructor is virtual since this class is designed to be 106 /// inherited from by the plug-in instance. 107 //------------------------------------------------------------------ 108 virtual 109 ~ObjectFile(); 110 111 //------------------------------------------------------------------ 112 /// Dump a description of this object to a Stream. 113 /// 114 /// Dump a description of the current contents of this object 115 /// to the supplied stream \a s. The dumping should include the 116 /// section list if it has been parsed, and the symbol table 117 /// if it has been parsed. 118 /// 119 /// @param[in] s 120 /// The stream to which to dump the object descripton. 121 //------------------------------------------------------------------ 122 virtual void 123 Dump (Stream *s) = 0; 124 125 //------------------------------------------------------------------ 126 /// Find a ObjectFile plug-in that can parse \a file_spec. 127 /// 128 /// Scans all loaded plug-in interfaces that implement versions of 129 /// the ObjectFile plug-in interface and returns the first 130 /// instance that can parse the file. 131 /// 132 /// @param[in] module 133 /// The parent module that owns this object file. 134 /// 135 /// @param[in] file_spec 136 /// A file specification that indicates which file to use as the 137 /// object file. 138 /// 139 /// @param[in] file_offset 140 /// The offset into the file at which to start parsing the 141 /// object. This is for files that contain multiple 142 /// architectures or objects. 143 /// 144 /// @param[in] file_size 145 /// The size of the current object file if it can be determined 146 /// or if it is known. This can be zero. 147 /// 148 /// @see ObjectFile::ParseHeader() 149 //------------------------------------------------------------------ 150 static lldb::ObjectFileSP 151 FindPlugin (const lldb::ModuleSP &module_sp, 152 const FileSpec* file_spec, 153 lldb::offset_t file_offset, 154 lldb::offset_t file_size, 155 lldb::DataBufferSP &data_sp, 156 lldb::offset_t &data_offset); 157 158 //------------------------------------------------------------------ 159 /// Find a ObjectFile plug-in that can parse a file in memory. 160 /// 161 /// Scans all loaded plug-in interfaces that implement versions of 162 /// the ObjectFile plug-in interface and returns the first 163 /// instance that can parse the file. 164 /// 165 /// @param[in] module 166 /// The parent module that owns this object file. 167 /// 168 /// @param[in] process_sp 169 /// A shared pointer to the process whose memory space contains 170 /// an object file. This will be stored as a std::weak_ptr. 171 /// 172 /// @param[in] header_addr 173 /// The address of the header for the object file in memory. 174 //------------------------------------------------------------------ 175 static lldb::ObjectFileSP 176 FindPlugin (const lldb::ModuleSP &module_sp, 177 const lldb::ProcessSP &process_sp, 178 lldb::addr_t header_addr, 179 lldb::DataBufferSP &file_data_sp); 180 181 182 static size_t 183 GetModuleSpecifications (const FileSpec &file, 184 lldb::offset_t file_offset, 185 lldb::offset_t file_size, 186 ModuleSpecList &specs); 187 188 static size_t 189 GetModuleSpecifications (const lldb_private::FileSpec& file, 190 lldb::DataBufferSP& data_sp, 191 lldb::offset_t data_offset, 192 lldb::offset_t file_offset, 193 lldb::offset_t file_size, 194 lldb_private::ModuleSpecList &specs); 195 //------------------------------------------------------------------ 196 /// Split a path into a file path with object name. 197 /// 198 /// For paths like "/tmp/foo.a(bar.o)" we often need to split a path 199 /// up into the actual path name and into the object name so we can 200 /// make a valid object file from it. 201 /// 202 /// @param[in] path_with_object 203 /// A path that might contain an archive path with a .o file 204 /// specified in parens in the basename of the path. 205 /// 206 /// @param[out] archive_file 207 /// If \b true is returned, \a file_spec will be filled in with 208 /// the path to the archive. 209 /// 210 /// @param[out] archive_object 211 /// If \b true is returned, \a object will be filled in with 212 /// the name of the object inside the archive. 213 /// 214 /// @return 215 /// \b true if the path matches the pattern of archive + object 216 /// and \a archive_file and \a archive_object are modified, 217 /// \b false otherwise and \a archive_file and \a archive_object 218 /// are guaranteed to be remain unchanged. 219 //------------------------------------------------------------------ 220 static bool 221 SplitArchivePathWithObject (const char *path_with_object, 222 lldb_private::FileSpec &archive_file, 223 lldb_private::ConstString &archive_object, 224 bool must_exist); 225 226 //------------------------------------------------------------------ 227 /// Gets the address size in bytes for the current object file. 228 /// 229 /// @return 230 /// The size of an address in bytes for the currently selected 231 /// architecture (and object for archives). Returns zero if no 232 /// architecture or object has been selected. 233 //------------------------------------------------------------------ 234 virtual uint32_t 235 GetAddressByteSize () const = 0; 236 237 //------------------------------------------------------------------ 238 /// Get the address type given a file address in an object file. 239 /// 240 /// Many binary file formats know what kinds 241 /// This is primarily for ARM binaries, though it can be applied to 242 /// any executable file format that supports different opcode types 243 /// within the same binary. ARM binaries support having both ARM and 244 /// Thumb within the same executable container. We need to be able 245 /// to get 246 /// @return 247 /// The size of an address in bytes for the currently selected 248 /// architecture (and object for archives). Returns zero if no 249 /// architecture or object has been selected. 250 //------------------------------------------------------------------ 251 virtual lldb::AddressClass 252 GetAddressClass (lldb::addr_t file_addr); 253 254 //------------------------------------------------------------------ 255 /// Extract the dependent modules from an object file. 256 /// 257 /// If an object file has information about which other images it 258 /// depends on (such as shared libraries), this function will 259 /// provide the list. Since many executables or shared libraries 260 /// may depend on the same files, 261 /// FileSpecList::AppendIfUnique(const FileSpec &) should be 262 /// used to make sure any files that are added are not already in 263 /// the list. 264 /// 265 /// @param[out] file_list 266 /// A list of file specification objects that gets dependent 267 /// files appended to. 268 /// 269 /// @return 270 /// The number of new files that were appended to \a file_list. 271 /// 272 /// @see FileSpecList::AppendIfUnique(const FileSpec &) 273 //------------------------------------------------------------------ 274 virtual uint32_t 275 GetDependentModules (FileSpecList& file_list) = 0; 276 277 //------------------------------------------------------------------ 278 /// Tells whether this object file is capable of being the main executable 279 /// for a process. 280 /// 281 /// @return 282 /// \b true if it is, \b false otherwise. 283 //------------------------------------------------------------------ 284 virtual bool 285 IsExecutable () const = 0; 286 287 //------------------------------------------------------------------ 288 /// Returns the offset into a file at which this object resides. 289 /// 290 /// Some files contain many object files, and this function allows 291 /// access to an object's offset within the file. 292 /// 293 /// @return 294 /// The offset in bytes into the file. Defaults to zero for 295 /// simple object files that a represented by an entire file. 296 //------------------------------------------------------------------ 297 virtual lldb::addr_t 298 GetFileOffset () const 299 { return m_file_offset; } 300 301 virtual lldb::addr_t 302 GetByteSize () const 303 { return m_length; } 304 305 //------------------------------------------------------------------ 306 /// Get accessor to the object file specification. 307 /// 308 /// @return 309 /// The file specification object pointer if there is one, or 310 /// NULL if this object is only from memory. 311 //------------------------------------------------------------------ 312 virtual FileSpec& 313 GetFileSpec() { return m_file; } 314 315 //------------------------------------------------------------------ 316 /// Get const accessor to the object file specification. 317 /// 318 /// @return 319 /// The const file specification object pointer if there is one, 320 /// or NULL if this object is only from memory. 321 //------------------------------------------------------------------ 322 virtual const FileSpec& 323 GetFileSpec() const { return m_file; } 324 325 //------------------------------------------------------------------ 326 /// Get the name of the cpu, vendor and OS for this object file. 327 /// 328 /// This value is a string that represents the target triple where 329 /// the cpu type, the vendor and the OS are encoded into a string. 330 /// 331 /// @param[out] target_triple 332 /// The string value of the target triple. 333 /// 334 /// @return 335 /// \b True if the target triple was able to be computed, \b 336 /// false otherwise. 337 //------------------------------------------------------------------ 338 virtual bool 339 GetArchitecture (ArchSpec &arch) = 0; 340 341 //------------------------------------------------------------------ 342 /// Gets the section list for the currently selected architecture 343 /// (and object for archives). 344 /// 345 /// Section list parsing can be deferred by ObjectFile instances 346 /// until this accessor is called the first time. 347 /// 348 /// @return 349 /// The list of sections contained in this object file. 350 //------------------------------------------------------------------ 351 virtual SectionList * 352 GetSectionList (); 353 354 virtual void 355 CreateSections (SectionList &unified_section_list) = 0; 356 357 //------------------------------------------------------------------ 358 /// Gets the symbol table for the currently selected architecture 359 /// (and object for archives). 360 /// 361 /// Symbol table parsing can be deferred by ObjectFile instances 362 /// until this accessor is called the first time. 363 /// 364 /// @return 365 /// The symbol table for this object file. 366 //------------------------------------------------------------------ 367 virtual Symtab * 368 GetSymtab () = 0; 369 370 //------------------------------------------------------------------ 371 /// Detect if this object file has been stripped of local symbols. 372 /// 373 /// @return 374 /// Return \b true if the object file has been stripped of local 375 /// symbols. 376 //------------------------------------------------------------------ 377 virtual bool 378 IsStripped () = 0; 379 380 //------------------------------------------------------------------ 381 /// Frees the symbol table. 382 /// 383 /// This function should only be used when an object file is 384 /// 385 /// @param[in] flags 386 /// eSymtabFromUnifiedSectionList: Whether to clear symbol table 387 /// for unified module section list, or object file. 388 /// 389 /// @return 390 /// The symbol table for this object file. 391 //------------------------------------------------------------------ 392 virtual void 393 ClearSymtab (); 394 395 //------------------------------------------------------------------ 396 /// Gets the UUID for this object file. 397 /// 398 /// If the object file format contains a UUID, the value should be 399 /// returned. Else ObjectFile instances should return the MD5 400 /// checksum of all of the bytes for the object file (or memory for 401 /// memory based object files). 402 /// 403 /// @return 404 /// Returns \b true if a UUID was successfully extracted into 405 /// \a uuid, \b false otherwise. 406 //------------------------------------------------------------------ 407 virtual bool 408 GetUUID (lldb_private::UUID* uuid) = 0; 409 410 //------------------------------------------------------------------ 411 /// Gets the symbol file spec list for this object file. 412 /// 413 /// If the object file format contains a debug symbol file link, 414 /// the values will be return in the FileSpecList. 415 /// 416 /// @return 417 /// Returns filespeclist. 418 //------------------------------------------------------------------ 419 virtual lldb_private::FileSpecList 420 GetDebugSymbolFilePaths() 421 { 422 return FileSpecList(); 423 } 424 425 //------------------------------------------------------------------ 426 /// Gets whether endian swapping should occur when extracting data 427 /// from this object file. 428 /// 429 /// @return 430 /// Returns \b true if endian swapping is needed, \b false 431 /// otherwise. 432 //------------------------------------------------------------------ 433 virtual lldb::ByteOrder 434 GetByteOrder () const = 0; 435 436 //------------------------------------------------------------------ 437 /// Attempts to parse the object header. 438 /// 439 /// This function is used as a test to see if a given plug-in 440 /// instance can parse the header data already contained in 441 /// ObjectFile::m_data. If an object file parser does not 442 /// recognize that magic bytes in a header, false should be returned 443 /// and the next plug-in can attempt to parse an object file. 444 /// 445 /// @return 446 /// Returns \b true if the header was parsed succesfully, \b 447 /// false otherwise. 448 //------------------------------------------------------------------ 449 virtual bool 450 ParseHeader () = 0; 451 452 //------------------------------------------------------------------ 453 /// Returns a reference to the UnwindTable for this ObjectFile 454 /// 455 /// The UnwindTable contains FuncUnwinders objects for any function in 456 /// this ObjectFile. If a FuncUnwinders object hasn't been created yet 457 /// (i.e. the function has yet to be unwound in a stack walk), it 458 /// will be created when requested. Specifically, we do not create 459 /// FuncUnwinders objects for functions until they are needed. 460 /// 461 /// @return 462 /// Returns the unwind table for this object file. 463 //------------------------------------------------------------------ 464 virtual lldb_private::UnwindTable& 465 GetUnwindTable () { return m_unwind_table; } 466 467 //------------------------------------------------------------------ 468 /// Similar to Process::GetImageInfoAddress(). 469 /// 470 /// Some platforms embed auxiliary structures useful to debuggers in the 471 /// address space of the inferior process. This method returns the address 472 /// of such a structure if the information can be resolved via entries in 473 /// the object file. ELF, for example, provides a means to hook into the 474 /// runtime linker so that a debugger may monitor the loading and unloading 475 /// of shared libraries. 476 /// 477 /// @return 478 /// The address of any auxiliary tables, or an invalid address if this 479 /// object file format does not support or contain such information. 480 virtual lldb_private::Address 481 GetImageInfoAddress () { return Address(); } 482 483 //------------------------------------------------------------------ 484 /// Returns the address of the Entry Point in this object file - if 485 /// the object file doesn't have an entry point (because it is not an 486 /// executable file) then an invalid address is returned. 487 /// 488 /// @return 489 /// Returns the entry address for this module. 490 //------------------------------------------------------------------ 491 virtual lldb_private::Address 492 GetEntryPointAddress () { return Address();} 493 494 //------------------------------------------------------------------ 495 /// Returns the address that represents the header of this object 496 /// file. 497 /// 498 /// The header address is defined as where the header for the object 499 /// file is that describes the content of the file. If the header 500 /// doesn't appear in a section that is defined in the object file, 501 /// an address with no section is returned that has the file offset 502 /// set in the m_file_offset member of the lldb_private::Address object. 503 /// 504 /// @return 505 /// Returns the entry address for this module. 506 //------------------------------------------------------------------ 507 virtual lldb_private::Address 508 GetHeaderAddress () { return Address(m_memory_addr);} 509 510 511 virtual uint32_t 512 GetNumThreadContexts () 513 { 514 return 0; 515 } 516 517 virtual lldb::RegisterContextSP 518 GetThreadContextAtIndex (uint32_t idx, lldb_private::Thread &thread) 519 { 520 return lldb::RegisterContextSP(); 521 } 522 523 //------------------------------------------------------------------ 524 /// The object file should be able to calculate its type by looking 525 /// at its file header and possibly the sections or other data in 526 /// the object file. The file type is used in the debugger to help 527 /// select the correct plug-ins for the job at hand, so this is 528 /// important to get right. If any eTypeXXX definitions do not match 529 /// up with the type of file you are loading, please feel free to 530 /// add a new enumeration value. 531 /// 532 /// @return 533 /// The calculated file type for the current object file. 534 //------------------------------------------------------------------ 535 virtual Type 536 CalculateType() = 0; 537 538 //------------------------------------------------------------------ 539 /// In cases where the type can't be calculated (elf files), this 540 /// routine allows someone to explicitly set it. As an example, 541 /// SymbolVendorELF uses this routine to set eTypeDebugInfo when 542 /// loading debug link files. 543 virtual void 544 SetType (Type type) 545 { 546 m_type = type; 547 } 548 549 //------------------------------------------------------------------ 550 /// The object file should be able to calculate the strata of the 551 /// object file. 552 /// 553 /// Many object files for platforms might be for either user space 554 /// debugging or for kernel debugging. If your object file subclass 555 /// can figure this out, it will help with debugger plug-in selection 556 /// when it comes time to debug. 557 /// 558 /// @return 559 /// The calculated object file strata for the current object 560 /// file. 561 //------------------------------------------------------------------ 562 virtual Strata 563 CalculateStrata() = 0; 564 565 //------------------------------------------------------------------ 566 /// Get the object file version numbers. 567 /// 568 /// Many object files have a set of version numbers that describe 569 /// the version of the executable or shared library. Typically there 570 /// are major, minor and build, but there may be more. This function 571 /// will extract the versions from object files if they are available. 572 /// 573 /// If \a versions is NULL, or if \a num_versions is 0, the return 574 /// value will indicate how many version numbers are available in 575 /// this object file. Then a subsequent call can be made to this 576 /// function with a value of \a versions and \a num_versions that 577 /// has enough storage to store some or all version numbers. 578 /// 579 /// @param[out] versions 580 /// A pointer to an array of uint32_t types that is \a num_versions 581 /// long. If this value is NULL, the return value will indicate 582 /// how many version numbers are required for a subsequent call 583 /// to this function so that all versions can be retrieved. If 584 /// the value is non-NULL, then at most \a num_versions of the 585 /// existing versions numbers will be filled into \a versions. 586 /// If there is no version information available, \a versions 587 /// will be filled with \a num_versions UINT32_MAX values 588 /// and zero will be returned. 589 /// 590 /// @param[in] num_versions 591 /// The maximum number of entries to fill into \a versions. If 592 /// this value is zero, then the return value will indicate 593 /// how many version numbers there are in total so another call 594 /// to this function can be make with adequate storage in 595 /// \a versions to get all of the version numbers. If \a 596 /// num_versions is less than the actual number of version 597 /// numbers in this object file, only \a num_versions will be 598 /// filled into \a versions (if \a versions is non-NULL). 599 /// 600 /// @return 601 /// This function always returns the number of version numbers 602 /// that this object file has regardless of the number of 603 /// version numbers that were copied into \a versions. 604 //------------------------------------------------------------------ 605 virtual uint32_t 606 GetVersion (uint32_t *versions, uint32_t num_versions) 607 { 608 if (versions && num_versions) 609 { 610 for (uint32_t i=0; i<num_versions; ++i) 611 versions[i] = UINT32_MAX; 612 } 613 return 0; 614 } 615 616 //------------------------------------------------------------------ 617 // Member Functions 618 //------------------------------------------------------------------ 619 Type 620 GetType () 621 { 622 if (m_type == eTypeInvalid) 623 m_type = CalculateType(); 624 return m_type; 625 } 626 627 Strata 628 GetStrata () 629 { 630 if (m_strata == eStrataInvalid) 631 m_strata = CalculateStrata(); 632 return m_strata; 633 } 634 635 // When an object file is in memory, subclasses should try and lock 636 // the process weak pointer. If the process weak pointer produces a 637 // valid ProcessSP, then subclasses can call this function to read 638 // memory. 639 static lldb::DataBufferSP 640 ReadMemory (const lldb::ProcessSP &process_sp, 641 lldb::addr_t addr, 642 size_t byte_size); 643 644 size_t 645 GetData (off_t offset, size_t length, DataExtractor &data) const; 646 647 size_t 648 CopyData (off_t offset, size_t length, void *dst) const; 649 650 size_t 651 ReadSectionData (const Section *section, 652 off_t section_offset, 653 void *dst, 654 size_t dst_len) const; 655 size_t 656 ReadSectionData (const Section *section, 657 DataExtractor& section_data) const; 658 659 size_t 660 MemoryMapSectionData (const Section *section, 661 DataExtractor& section_data) const; 662 663 bool 664 IsInMemory () const 665 { 666 return m_memory_addr != LLDB_INVALID_ADDRESS; 667 } 668 669 protected: 670 //------------------------------------------------------------------ 671 // Member variables. 672 //------------------------------------------------------------------ 673 FileSpec m_file; 674 Type m_type; 675 Strata m_strata; 676 lldb::addr_t m_file_offset; ///< The offset in bytes into the file, or the address in memory 677 lldb::addr_t m_length; ///< The length of this object file if it is known (can be zero if length is unknown or can't be determined). 678 DataExtractor m_data; ///< The data for this object file so things can be parsed lazily. 679 lldb_private::UnwindTable m_unwind_table; /// < Table of FuncUnwinders objects created for this ObjectFile's functions 680 lldb::ProcessWP m_process_wp; 681 const lldb::addr_t m_memory_addr; 682 std::unique_ptr<lldb_private::SectionList> m_sections_ap; 683 std::unique_ptr<lldb_private::Symtab> m_symtab_ap; 684 685 //------------------------------------------------------------------ 686 /// Sets the architecture for a module. At present the architecture 687 /// can only be set if it is invalid. It is not allowed to switch from 688 /// one concrete architecture to another. 689 /// 690 /// @param[in] new_arch 691 /// The architecture this module will be set to. 692 /// 693 /// @return 694 /// Returns \b true if the architecture was changed, \b 695 /// false otherwise. 696 //------------------------------------------------------------------ 697 bool SetModulesArchitecture (const ArchSpec &new_arch); 698 699 private: 700 DISALLOW_COPY_AND_ASSIGN (ObjectFile); 701 }; 702 703 } // namespace lldb_private 704 705 #endif // liblldb_ObjectFile_h_ 706 707
