Basic support for parsing Mach-O universal binaries in LLVMObject library
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184191 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Object/MachOUniversal.cpp b/lib/Object/MachOUniversal.cpp
new file mode 100644
index 0000000..98f7198
--- /dev/null
+++ b/lib/Object/MachOUniversal.cpp
@@ -0,0 +1,139 @@
+//===- MachOUniversal.cpp - Mach-O universal binary -------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the MachOUniversalBinary class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Object/MachOUniversal.h"
+
+#include "llvm/Object/MachO.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/Host.h"
+#include "llvm/Support/MemoryBuffer.h"
+
+using namespace llvm;
+using namespace object;
+
+template<typename T>
+static void SwapValue(T &Value) {
+ Value = sys::SwapByteOrder(Value);
+}
+
+template<typename T>
+static void SwapStruct(T &Value);
+
+template<>
+void SwapStruct(macho::FatHeader &H) {
+ SwapValue(H.Magic);
+ SwapValue(H.NumFatArch);
+}
+
+template<>
+void SwapStruct(macho::FatArchHeader &H) {
+ SwapValue(H.CPUType);
+ SwapValue(H.CPUSubtype);
+ SwapValue(H.Offset);
+ SwapValue(H.Size);
+ SwapValue(H.Align);
+}
+
+template<typename T>
+static T getUniversalBinaryStruct(const char *Ptr) {
+ T Res;
+ memcpy(&Res, Ptr, sizeof(T));
+ // Universal binary headers have big-endian byte order.
+ if (sys::IsLittleEndianHost)
+ SwapStruct(Res);
+ return Res;
+}
+
+MachOUniversalBinary::ObjectForArch::ObjectForArch(
+ const MachOUniversalBinary *Parent, uint32_t Index)
+ : Parent(Parent), Index(Index) {
+ if (Parent == 0 || Index > Parent->getNumberOfObjects()) {
+ clear();
+ } else {
+ // Parse object header.
+ StringRef ParentData = Parent->getData();
+ const char *HeaderPos = ParentData.begin() + macho::FatHeaderSize +
+ Index * macho::FatArchHeaderSize;
+ Header = getUniversalBinaryStruct<macho::FatArchHeader>(HeaderPos);
+ if (ParentData.size() < Header.Offset + Header.Size) {
+ clear();
+ }
+ }
+}
+
+error_code MachOUniversalBinary::ObjectForArch::getAsObjectFile(
+ OwningPtr<ObjectFile> &Result) const {
+ if (Parent) {
+ StringRef ParentData = Parent->getData();
+ StringRef ObjectData = ParentData.substr(Header.Offset, Header.Size);
+ Twine ObjectName =
+ Twine(Parent->getFileName()) + ":" +
+ Triple::getArchTypeName(MachOObjectFile::getArch(Header.CPUType));
+ MemoryBuffer *ObjBuffer = MemoryBuffer::getMemBuffer(
+ ObjectData, ObjectName.str(), false);
+ if (ObjectFile *Obj = ObjectFile::createMachOObjectFile(ObjBuffer)) {
+ Result.reset(Obj);
+ return object_error::success;
+ }
+ }
+ return object_error::parse_failed;
+}
+
+void MachOUniversalBinary::anchor() { }
+
+MachOUniversalBinary::MachOUniversalBinary(MemoryBuffer *Source,
+ error_code &ec)
+ : Binary(Binary::ID_MachOUniversalBinary, Source),
+ NumberOfObjects(0) {
+ if (Source->getBufferSize() < macho::FatHeaderSize) {
+ ec = object_error::invalid_file_type;
+ return;
+ }
+ // Check for magic value and sufficient header size.
+ StringRef Buf = getData();
+ macho::FatHeader H = getUniversalBinaryStruct<macho::FatHeader>(Buf.begin());
+ NumberOfObjects = H.NumFatArch;
+ uint32_t MinSize = macho::FatHeaderSize +
+ macho::FatArchHeaderSize * NumberOfObjects;
+ if (H.Magic != macho::HM_Universal || Buf.size() < MinSize) {
+ ec = object_error::parse_failed;
+ return;
+ }
+ ec = object_error::success;
+}
+
+static bool getCTMForArch(Triple::ArchType Arch, mach::CPUTypeMachine &CTM) {
+ switch (Arch) {
+ case Triple::x86: CTM = mach::CTM_i386; return true;
+ case Triple::x86_64: CTM = mach::CTM_x86_64; return true;
+ case Triple::arm: CTM = mach::CTM_ARM; return true;
+ case Triple::sparc: CTM = mach::CTM_SPARC; return true;
+ case Triple::ppc: CTM = mach::CTM_PowerPC; return true;
+ case Triple::ppc64: CTM = mach::CTM_PowerPC64; return true;
+ default: return false;
+ }
+}
+
+error_code
+MachOUniversalBinary::getObjectForArch(Triple::ArchType Arch,
+ OwningPtr<ObjectFile> &Result) const {
+ mach::CPUTypeMachine CTM;
+ if (!getCTMForArch(Arch, CTM))
+ return object_error::arch_not_found;
+ for (object_iterator I = begin_objects(), E = end_objects(); I != E; ++I) {
+ if (I->getCPUType() == static_cast<uint32_t>(CTM))
+ return I->getAsObjectFile(Result);
+ }
+ return object_error::arch_not_found;
+}