//===-- ObjectFile.h --------------------------------------------*- C++ -*-===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// #ifndef liblldb_ObjectFile_h_ #define liblldb_ObjectFile_h_ #include "lldb/lldb-private.h" #include "lldb/Core/DataExtractor.h" #include "lldb/Host/FileSpec.h" #include "lldb/Core/ModuleChild.h" #include "lldb/Core/PluginInterface.h" #include "lldb/Host/Endian.h" #include "lldb/Symbol/Symtab.h" #include "lldb/Symbol/UnwindTable.h" namespace lldb_private { //---------------------------------------------------------------------- /// @class ObjectFile ObjectFile.h "lldb/Symbol/ObjectFile.h" /// @brief A plug-in interface definition class for object file parsers. /// /// Object files belong to Module objects and know how to extract /// information from executable, shared library, and object (.o) files /// used by operating system runtime. The symbol table and section list /// for an object file. /// /// Object files can be represented by the entire file, or by part of a /// file. Examples of object files that are part of a file include /// object files that contain information for multiple architectures in /// the same file, or archive files that contain multiple objects /// (ranlib archives) (possibly for multiple architectures as well). /// /// Object archive files (e.g. ranlib archives) can contain /// multiple .o (object) files that must be selected by index or by name. /// The number of objects that an ObjectFile contains can be determined /// using the ObjectFile::GetNumObjects() const /// function, and followed by a call to /// ObjectFile::SelectObjectAtIndex (uint32_t) to change the currently /// selected object. Objects can also be selected by name using the /// ObjectFile::SelectObject(const char *) function. /// /// Once an architecture is selected (and an object is selected for /// for archives), the object file information can be extracted from /// this abstract class. //---------------------------------------------------------------------- class ObjectFile: public PluginInterface, public ModuleChild { friend class lldb_private::Module; public: typedef enum { eTypeInvalid = 0, eTypeCoreFile, /// A core file that has a checkpoint of a program's execution state eTypeExecutable, /// A normal executable eTypeDebugInfo, /// An object file that contains only debug information eTypeDynamicLinker, /// The platform's dynamic linker executable eTypeObjectFile, /// An intermediate object file eTypeSharedLibrary, /// A shared library that can be used during execution eTypeStubLibrary, /// A library that can be linked against but not used for execution eTypeUnknown } Type; typedef enum { eStrataInvalid = 0, eStrataUnknown, eStrataUser, eStrataKernel } Strata; //------------------------------------------------------------------ /// Construct with a parent module, offset, and header data. /// /// Object files belong to modules and a valid module must be /// supplied upon construction. The at an offset within a file for /// objects that contain more than one architecture or object. //------------------------------------------------------------------ ObjectFile (Module* module, const FileSpec *file_spec_ptr, lldb::addr_t offset, lldb::addr_t length, lldb::DataBufferSP& headerDataSP) : ModuleChild (module), m_file (), // This file could be different from the original module's file m_type (eTypeInvalid), m_strata (eStrataInvalid), m_offset (offset), m_length (length), m_data (headerDataSP, lldb::endian::InlHostByteOrder(), 4), m_unwind_table (*this) { if (file_spec_ptr) m_file = *file_spec_ptr; } //------------------------------------------------------------------ /// Destructor. /// /// The destructor is virtual since this class is designed to be /// inherited from by the plug-in instance. //------------------------------------------------------------------ virtual ~ObjectFile() { } //------------------------------------------------------------------ /// Dump a description of this object to a Stream. /// /// Dump a description of the current contents of this object /// to the supplied stream \a s. The dumping should include the /// section list if it has been parsed, and the symbol table /// if it has been parsed. /// /// @param[in] s /// The stream to which to dump the object descripton. //------------------------------------------------------------------ virtual void Dump (Stream *s) = 0; //------------------------------------------------------------------ /// Find a ObjectFile plug-in that can parse \a file_spec. /// /// Scans all loaded plug-in interfaces that implement versions of /// the ObjectFile plug-in interface and returns the first /// instance that can parse the file. /// /// @param[in] module /// The parent module that owns this object file. /// /// @param[in] file_spec /// A file specification that indicates which file to use as the /// object file. /// /// @param[in] file_offset /// The offset into the file at which to start parsing the /// object. This is for files that contain multiple /// architectures or objects. /// /// @param[in] file_size /// The size of the current object file if it can be determined /// or if it is known. This can be zero. /// /// @see ObjectFile::ParseHeader() //------------------------------------------------------------------ static ObjectFile* FindPlugin (Module* module, const FileSpec* file_spec, lldb::addr_t file_offset, lldb::addr_t file_size); //------------------------------------------------------------------ /// Gets the address size in bytes for the current object file. /// /// @return /// The size of an address in bytes for the currently selected /// architecture (and object for archives). Returns zero if no /// architecture or object has been selected. //------------------------------------------------------------------ virtual size_t GetAddressByteSize () const = 0; //------------------------------------------------------------------ /// Get the address type given a file address in an object file. /// /// Many binary file formats know what kinds /// This is primarily for ARM binaries, though it can be applied to /// any executable file format that supports different opcode types /// within the same binary. ARM binaries support having both ARM and /// Thumb within the same executable container. We need to be able /// to get /// @return /// The size of an address in bytes for the currently selected /// architecture (and object for archives). Returns zero if no /// architecture or object has been selected. //------------------------------------------------------------------ virtual AddressClass GetAddressClass (lldb::addr_t file_addr); //------------------------------------------------------------------ /// Extract the dependent modules from an object file. /// /// If an object file has information about which other images it /// depends on (such as shared libraries), this function will /// provide the list. Since many executables or shared libraries /// may depend on the same files, /// FileSpecList::AppendIfUnique(const FileSpec &) should be /// used to make sure any files that are added are not already in /// the list. /// /// @param[out] file_list /// A list of file specification objects that gets dependent /// files appended to. /// /// @return /// The number of new files that were appended to \a file_list. /// /// @see FileSpecList::AppendIfUnique(const FileSpec &) //------------------------------------------------------------------ virtual uint32_t GetDependentModules (FileSpecList& file_list) = 0; //------------------------------------------------------------------ /// Tells whether this object file is capable of being the main executable /// for a process. /// /// @return /// \b true if it is, \b false otherwise. //------------------------------------------------------------------ virtual bool IsExecutable () const = 0; //------------------------------------------------------------------ /// Returns the offset into a file at which this object resides. /// /// Some files contain many object files, and this function allows /// access to an object's offset within the file. /// /// @return /// The offset in bytes into the file. Defaults to zero for /// simple object files that a represented by an entire file. //------------------------------------------------------------------ virtual lldb::addr_t GetOffset () const { return m_offset; } virtual lldb::addr_t GetByteSize () const { return m_length; } //------------------------------------------------------------------ /// Get accessor to the object file specification. /// /// @return /// The file specification object pointer if there is one, or /// NULL if this object is only from memory. //------------------------------------------------------------------ virtual FileSpec& GetFileSpec() { return m_file; } //------------------------------------------------------------------ /// Get const accessor to the object file specification. /// /// @return /// The const file specification object pointer if there is one, /// or NULL if this object is only from memory. //------------------------------------------------------------------ virtual const FileSpec& GetFileSpec() const { return m_file; } //------------------------------------------------------------------ /// Get the name of the cpu, vendor and OS for this object file. /// /// This value is a string that represents the target triple where /// the cpu type, the vendor and the OS are encoded into a string. /// /// @param[out] target_triple /// The string value of the target triple. /// /// @return /// \b True if the target triple was able to be computed, \b /// false otherwise. //------------------------------------------------------------------ virtual bool GetArchitecture (ArchSpec &arch) = 0; //------------------------------------------------------------------ /// Gets the section list for the currently selected architecture /// (and object for archives). /// /// Section list parsing can be deferred by ObjectFile instances /// until this accessor is called the first time. /// /// @return /// The list of sections contained in this object file. //------------------------------------------------------------------ virtual SectionList * GetSectionList () = 0; //------------------------------------------------------------------ /// Gets the symbol table for the currently selected architecture /// (and object for archives). /// /// Symbol table parsing can be deferred by ObjectFile instances /// until this accessor is called the first time. /// /// @return /// The symbol table for this object file. //------------------------------------------------------------------ virtual Symtab * GetSymtab () = 0; //------------------------------------------------------------------ /// Gets the UUID for this object file. /// /// If the object file format contains a UUID, the value should be /// returned. Else ObjectFile instances should return the MD5 /// checksum of all of the bytes for the object file (or memory for /// memory based object files). /// /// @return /// Returns \b true if a UUID was successfully extracted into /// \a uuid, \b false otherwise. //------------------------------------------------------------------ virtual bool GetUUID (lldb_private::UUID* uuid) = 0; //------------------------------------------------------------------ /// Gets whether endian swapping should occur when extracting data /// from this object file. /// /// @return /// Returns \b true if endian swapping is needed, \b false /// otherwise. //------------------------------------------------------------------ virtual lldb::ByteOrder GetByteOrder () const = 0; //------------------------------------------------------------------ /// Attempts to parse the object header. /// /// This function is used as a test to see if a given plug-in /// instance can parse the header data already contained in /// ObjectFile::m_data. If an object file parser does not /// recognize that magic bytes in a header, false should be returned /// and the next plug-in can attempt to parse an object file. /// /// @return /// Returns \b true if the header was parsed succesfully, \b /// false otherwise. //------------------------------------------------------------------ virtual bool ParseHeader () = 0; //------------------------------------------------------------------ /// Returns a reference to the UnwindTable for this ObjectFile /// /// The UnwindTable contains FuncUnwinders objects for any function in /// this ObjectFile. If a FuncUnwinders object hasn't been created yet /// (i.e. the function has yet to be unwound in a stack walk), it /// will be created when requested. Specifically, we do not create /// FuncUnwinders objects for functions until they are needed. /// /// @return /// Returns the unwind table for this object file. //------------------------------------------------------------------ virtual lldb_private::UnwindTable& GetUnwindTable () { return m_unwind_table; } //------------------------------------------------------------------ /// Similar to Process::GetImageInfoAddress(). /// /// Some platforms embed auxiliary structures useful to debuggers in the /// address space of the inferior process. This method returns the address /// of such a structure if the information can be resolved via entries in /// the object file. ELF, for example, provides a means to hook into the /// runtime linker so that a debugger may monitor the loading and unloading /// of shared libraries. /// /// @return /// The address of any auxiliary tables, or an invalid address if this /// object file format does not support or contain such information. virtual lldb_private::Address GetImageInfoAddress () { return Address(); } //------------------------------------------------------------------ /// Returns the address of the Entry Point in this object file - if /// the object file doesn't have an entry point (because it is not an /// executable file) then an invalid address is returned. /// /// @return /// Returns the entry address for this module. //------------------------------------------------------------------ virtual lldb_private::Address GetEntryPointAddress () { return Address();} //------------------------------------------------------------------ /// The object file should be able to calculate its type by looking /// at its file header and possibly the sections or other data in /// the object file. The file type is used in the debugger to help /// select the correct plug-ins for the job at hand, so this is /// important to get right. If any eTypeXXX definitions do not match /// up with the type of file you are loading, please feel free to /// add a new enumeration value. /// /// @return /// The calculated file type for the current object file. //------------------------------------------------------------------ virtual Type CalculateType() = 0; //------------------------------------------------------------------ /// The object file should be able to calculate the strata of the /// object file. /// /// Many object files for platforms might be for either user space /// debugging or for kernel debugging. If your object file subclass /// can figure this out, it will help with debugger plug-in selection /// when it comes time to debug. /// /// @return /// The calculated object file strata for the current object /// file. //------------------------------------------------------------------ virtual Strata CalculateStrata() = 0; //------------------------------------------------------------------ // Member Functions //------------------------------------------------------------------ Type GetType () { if (m_type == eTypeInvalid) m_type = CalculateType(); return m_type; } Strata GetStrata () { if (m_strata == eStrataInvalid) m_strata = CalculateStrata(); return m_strata; } protected: //------------------------------------------------------------------ // Member variables. //------------------------------------------------------------------ FileSpec m_file; Type m_type; Strata m_strata; lldb::addr_t m_offset; ///< The offset in bytes into the file, or the address in memory 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). DataExtractor m_data; ///< The data for this object file so things can be parsed lazily. lldb_private::UnwindTable m_unwind_table; /// < Table of FuncUnwinders objects created for this ObjectFile's functions //------------------------------------------------------------------ /// Sets the architecture for a module. At present the architecture /// can only be set if it is invalid. It is not allowed to switch from /// one concrete architecture to another. /// /// @param[in] new_arch /// The architecture this module will be set to. /// /// @return /// Returns \b true if the architecture was changed, \b /// false otherwise. //------------------------------------------------------------------ bool SetModulesArchitecture (const ArchSpec &new_arch); private: DISALLOW_COPY_AND_ASSIGN (ObjectFile); }; } // namespace lldb_private #endif // liblldb_ObjectFile_h_