1 //===- MachOObject.h - Mach-O Object File Wrapper ---------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #ifndef LLVM_OBJECT_MACHOOBJECT_H
11 #define LLVM_OBJECT_MACHOOBJECT_H
14 #include "llvm/ADT/InMemoryStruct.h"
15 #include "llvm/ADT/OwningPtr.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/Object/MachOFormat.h"
25 /// \brief Wrapper object for manipulating Mach-O object files.
27 /// This class is designed to implement a full-featured, efficient, portable,
28 /// and robust Mach-O interface to Mach-O object files. It does not attempt to
29 /// smooth over rough edges in the Mach-O format or generalize access to object
30 /// independent features.
32 /// The class is designed around accessing the Mach-O object which is expected
33 /// to be fully loaded into memory.
35 /// This class is *not* suitable for concurrent use. For efficient operation,
36 /// the class uses APIs which rely on the ability to cache the results of
37 /// certain calls in internal objects which are not safe for concurrent
38 /// access. This allows the API to be zero-copy on the common paths.
40 // FIXME: It would be cool if we supported a "paged" MemoryBuffer
41 // implementation. This would allow us to implement a more sensible version of
42 // MemoryObject which can work like a MemoryBuffer, but be more efficient for
43 // objects which are in the current address space.
46 struct LoadCommandInfo {
47 /// The load command information.
48 macho::LoadCommand Command;
50 /// The offset to the start of the load command in memory.
55 OwningPtr<MemoryBuffer> Buffer;
57 /// Whether the object is little endian.
59 /// Whether the object is 64-bit.
61 /// Whether the object is swapped endianness from the host.
63 /// Whether the string table has been registered.
66 /// The cached information on the load commands.
67 LoadCommandInfo *LoadCommands;
68 mutable unsigned NumLoadedCommands;
70 /// The cached copy of the header.
72 macho::Header64Ext Header64Ext;
74 /// Cache string table information.
75 StringRef StringTable;
78 MachOObject(MemoryBuffer *Buffer, bool IsLittleEndian, bool Is64Bit);
83 /// \brief Load a Mach-O object from a MemoryBuffer object.
85 /// \param Buffer - The buffer to load the object from. This routine takes
86 /// exclusive ownership of the buffer (which is passed to the returned object
88 /// \param ErrorStr [out] - If given, will be set to a user readable error
89 /// message on failure.
90 /// \returns The loaded object, or null on error.
91 static MachOObject *LoadFromBuffer(MemoryBuffer *Buffer,
92 std::string *ErrorStr = 0);
94 /// @name File Information
97 bool isLittleEndian() const { return IsLittleEndian; }
98 bool isSwappedEndian() const { return IsSwappedEndian; }
99 bool is64Bit() const { return Is64Bit; }
101 unsigned getHeaderSize() const {
102 return Is64Bit ? macho::Header64Size : macho::Header32Size;
105 StringRef getData(size_t Offset, size_t Size) const;
108 /// @name String Table Data
111 StringRef getStringTableData() const {
112 assert(HasStringTable && "String table has not been registered!");
116 StringRef getStringAtIndex(unsigned Index) const {
117 size_t End = getStringTableData().find('\0', Index);
118 return getStringTableData().slice(Index, End);
121 void RegisterStringTable(macho::SymtabLoadCommand &SLC);
124 /// @name Object Header Access
127 const macho::Header &getHeader() const { return Header; }
128 const macho::Header64Ext &getHeader64Ext() const {
129 assert(is64Bit() && "Invalid access!");
134 /// @name Object Structure Access
137 /// \brief Retrieve the information for the given load command.
138 const LoadCommandInfo &getLoadCommandInfo(unsigned Index) const;
140 void ReadSegmentLoadCommand(
141 const LoadCommandInfo &LCI,
142 InMemoryStruct<macho::SegmentLoadCommand> &Res) const;
143 void ReadSegment64LoadCommand(
144 const LoadCommandInfo &LCI,
145 InMemoryStruct<macho::Segment64LoadCommand> &Res) const;
146 void ReadSymtabLoadCommand(
147 const LoadCommandInfo &LCI,
148 InMemoryStruct<macho::SymtabLoadCommand> &Res) const;
149 void ReadDysymtabLoadCommand(
150 const LoadCommandInfo &LCI,
151 InMemoryStruct<macho::DysymtabLoadCommand> &Res) const;
152 void ReadIndirectSymbolTableEntry(
153 const macho::DysymtabLoadCommand &DLC,
155 InMemoryStruct<macho::IndirectSymbolTableEntry> &Res) const;
157 const LoadCommandInfo &LCI,
159 InMemoryStruct<macho::Section> &Res) const;
161 const LoadCommandInfo &LCI,
163 InMemoryStruct<macho::Section64> &Res) const;
164 void ReadRelocationEntry(
165 uint64_t RelocationTableOffset, unsigned Index,
166 InMemoryStruct<macho::RelocationEntry> &Res) const;
167 void ReadSymbolTableEntry(
168 uint64_t SymbolTableOffset, unsigned Index,
169 InMemoryStruct<macho::SymbolTableEntry> &Res) const;
170 void ReadSymbol64TableEntry(
171 uint64_t SymbolTableOffset, unsigned Index,
172 InMemoryStruct<macho::Symbol64TableEntry> &Res) const;
177 } // end namespace object
178 } // end namespace llvm