Object/Mach-O: Add header and load command information.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120198 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Object/MachOFormat.h

@@ -22,6 +22,8 @@
 #ifndef LLVM_OBJECT_MACHOFORMAT_H
 #define LLVM_OBJECT_MACHOFORMAT_H
 
+#include "llvm/System/DataTypes.h"
+
 namespace llvm {
 namespace object {
 
@@ -83,13 +85,6 @@ namespace mach {
 
 /// Format information for Mach object files.
 namespace macho {
-  /// \brief Constants for header magic field.
-  enum HeaderMagic {
-    HM_Object32 = 0xFEEDFACE,  ///< 32-bit mach object file
-    HM_Object64 = 0xFEEDFACF,  ///< 64-bit mach object file
-    HM_Universal = 0xCAFEBABE  ///< Universal object file
-  };
-
   /// \brief Constants for structure sizes.
   enum StructureSizes {
     Header32Size = 28,
@@ -105,6 +100,29 @@ namespace macho {
     RelocationInfoSize = 8
   };
 
+  /// \brief Constants for header magic field.
+  enum HeaderMagic {
+    HM_Object32 = 0xFEEDFACE,  ///< 32-bit mach object file
+    HM_Object64 = 0xFEEDFACF,  ///< 64-bit mach object file
+    HM_Universal = 0xCAFEBABE  ///< Universal object file
+  };
+
+  /// \brief Header common to all Mach object files.
+  struct Header {
+    uint32_t Magic;
+    uint32_t CPUType;
+    uint32_t CPUSubtype;
+    uint32_t FileType;
+    uint32_t NumLoadCommands;
+    uint32_t SizeOfLoadCommands;
+    uint32_t Flags;
+  };
+
+  /// \brief Extended header for 64-bit object files.
+  struct Header64Ext {
+    uint32_t Reserved;
+  };
+
   // See <mach-o/loader.h>.
   enum HeaderFileType {
     HFT_Object = 0x1
@@ -118,7 +136,14 @@ namespace macho {
     LCT_Segment = 0x1,
     LCT_Symtab = 0x2,
     LCT_Dysymtab = 0xb,
-    LCT_Segment64 = 0x19
+    LCT_Segment64 = 0x19,
+    LCT_UUID = 0x1b
+  };
+
+  /// \brief Load command structure.
+  struct LoadCommand {
+    uint32_t Type;
+    uint32_t Size;
   };
 
   // See <mach-o/nlist.h>.

include/llvm/Object/MachOObject.h

@@ -12,6 +12,7 @@
 
 #include <string>
 #include "llvm/ADT/OwningPtr.h"
+#include "llvm/Object/MachOFormat.h"
 
 namespace llvm {
 
@@ -40,6 +41,13 @@ namespace object {
 // objects which are in the current address space.
 class MachOObject {
 public:
+  struct LoadCommandInfo {
+    /// The load command information.
+    macho::LoadCommand Command;
+
+    /// The offset to the start of the load command in memory.
+    uint64_t Offset;
+  };
 
 private:
   OwningPtr<MemoryBuffer> Buffer;
@@ -48,11 +56,23 @@ private:
   bool IsLittleEndian;
   /// Whether the object is 64-bit.
   bool Is64Bit;
+  /// Whether the object is swapped endianness from the host.
+  bool IsSwappedEndian;
+
+  /// The cached information on the load commands.
+  LoadCommandInfo *LoadCommands;
+  mutable unsigned NumLoadedCommands;
+
+  /// The cached copy of the header.
+  macho::Header Header;
+  macho::Header64Ext Header64Ext;
 
 private:
   MachOObject(MemoryBuffer *Buffer, bool IsLittleEndian, bool Is64Bit);
 
 public:
+  ~MachOObject();
+
   /// \brief Load a Mach-O object from a MemoryBuffer object.
   ///
   /// \param Buffer - The buffer to load the object from. This routine takes
@@ -64,8 +84,33 @@ public:
   static MachOObject *LoadFromBuffer(MemoryBuffer *Buffer,
                                      std::string *ErrorStr = 0);
 
-  /// @name Object Header Information
+  /// @name File Information
   /// @{
+
+  bool isLittleEndian() const { return IsLittleEndian; }
+  bool is64Bit() const { return Is64Bit; }
+
+  unsigned getHeaderSize() const {
+    return Is64Bit ? macho::Header64Size : macho::Header32Size;
+  }
+
+  /// @}
+  /// @name Object Header Access
+  /// @{
+
+  const macho::Header &getHeader() const { return Header; }
+  const macho::Header64Ext &getHeader64Ext() const {
+    assert(is64Bit() && "Invalid access!");
+    return Header64Ext;
+  }
+
+  /// @}
+  /// @name Object Structure Access
+  /// @{
+
+  /// \brief Retrieve the information for the given load command.
+  const LoadCommandInfo &getLoadCommandInfo(unsigned Index) const;
+
   /// @}
 };