Replace trivial use of external rc.exe by writing our own .res file.

This patch removes the dependency on the external rc.exe tool by writing
a simple .res file using our own library. In this patch I also added an
explicit definition for the .res file magic.  Furthermore, I added a
unittest for embeded manifests and fixed a bug exposed by the test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306311 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/BinaryFormat/COFF.h

@@ -46,6 +46,12 @@ static const char ClGlObjMagic[] = {
     '\xac', '\x9b', '\xd6', '\xb6', '\x22', '\x26', '\x53', '\xc2',
 };
 
+// The signature bytes that start a .res file.
+static const char WinResMagic[] = {
+    '\x00', '\x00', '\x00', '\x00', '\x20', '\x00', '\x00', '\x00',
+    '\xff', '\xff', '\x00', '\x00', '\xff', '\xff', '\x00', '\x00',
+};
+
 // Sizes in bytes of various things in the COFF format.
 enum {
   Header16Size = 20,

include/llvm/Object/WindowsResource.h

@@ -47,6 +47,44 @@ namespace object {
 
 class WindowsResource;
 
+const size_t WIN_RES_MAGIC_SIZE = 16;
+const size_t WIN_RES_NULL_ENTRY_SIZE = 16;
+const uint32_t WIN_RES_HEADER_ALIGNMENT = 4;
+const uint32_t WIN_RES_DATA_ALIGNMENT = 4;
+const uint16_t WIN_RES_PURE_MOVEABLE = 0x0030;
+
+struct WinResHeaderPrefix {
+  support::ulittle32_t DataSize;
+  support::ulittle32_t HeaderSize;
+};
+
+// Type and Name may each either be an integer ID or a string.  This struct is
+// only used in the case where they are both IDs.
+struct WinResIDs {
+  uint16_t TypeFlag;
+  support::ulittle16_t TypeID;
+  uint16_t NameFlag;
+  support::ulittle16_t NameID;
+
+  void setType(uint16_t ID) {
+    TypeFlag = 0xffff;
+    TypeID = ID;
+  }
+
+  void setName(uint16_t ID) {
+    NameFlag = 0xffff;
+    NameID = ID;
+  }
+};
+
+struct WinResHeaderSuffix {
+  support::ulittle32_t DataVersion;
+  support::ulittle16_t MemoryFlags;
+  support::ulittle16_t Language;
+  support::ulittle32_t Version;
+  support::ulittle32_t Characteristics;
+};
+
 class ResourceEntryRef {
 public:
   Error moveNext(bool &End);
@@ -70,14 +108,6 @@ private:
 
   Error loadNext();
 
-  struct HeaderSuffix {
-    support::ulittle32_t DataVersion;
-    support::ulittle16_t MemoryFlags;
-    support::ulittle16_t Language;
-    support::ulittle32_t Version;
-    support::ulittle32_t Characteristics;
-  };
-
   BinaryStreamReader Reader;
   bool IsStringType;
   ArrayRef<UTF16> Type;
@@ -85,7 +115,7 @@ private:
   bool IsStringName;
   ArrayRef<UTF16> Name;
   uint16_t NameID;
-  const HeaderSuffix *Suffix = nullptr;
+  const WinResHeaderSuffix *Suffix = nullptr;
   ArrayRef<uint8_t> Data;
   const WindowsResource *OwningRes = nullptr;
 };

lib/BinaryFormat/Magic.cpp

@@ -51,7 +51,8 @@ file_magic llvm::identify_magic(StringRef Magic) {
       return file_magic::coff_import_library;
     }
     // Windows resource file
-    if (startswith(Magic, "\0\0\0\0\x20\0\0\0\xFF"))
+    if (Magic.size() >= sizeof(COFF::WinResMagic) &&
+        memcmp(Magic.data(), COFF::WinResMagic, sizeof(COFF::WinResMagic)) == 0)
       return file_magic::windows_resource;
     // 0x0000 = COFF unknown machine type
     if (Magic[1] == 0)

lib/Object/WindowsResource.cpp

@@ -36,23 +36,19 @@ const uint32_t MIN_HEADER_SIZE = 7 * sizeof(uint32_t) + 2 * sizeof(uint16_t);
 // 8-byte because it makes everyone happy.
 const uint32_t SECTION_ALIGNMENT = sizeof(uint64_t);
 
-static const size_t ResourceMagicSize = 16;
-
-static const size_t NullEntrySize = 16;
-
 uint32_t WindowsResourceParser::TreeNode::StringCount = 0;
 uint32_t WindowsResourceParser::TreeNode::DataCount = 0;
 
 WindowsResource::WindowsResource(MemoryBufferRef Source)
     : Binary(Binary::ID_WinRes, Source) {
-  size_t LeadingSize = ResourceMagicSize + NullEntrySize;
+  size_t LeadingSize = WIN_RES_MAGIC_SIZE + WIN_RES_NULL_ENTRY_SIZE;
   BBS = BinaryByteStream(Data.getBuffer().drop_front(LeadingSize),
                          support::little);
 }
 
 Expected<std::unique_ptr<WindowsResource>>
 WindowsResource::createWindowsResource(MemoryBufferRef Source) {
-  if (Source.getBufferSize() < ResourceMagicSize + NullEntrySize)
+  if (Source.getBufferSize() < WIN_RES_MAGIC_SIZE + WIN_RES_NULL_ENTRY_SIZE)
     return make_error<GenericBinaryError>(
         "File too small to be a resource file",
         object_error::invalid_file_type);
@@ -105,12 +101,10 @@ static Error readStringOrId(BinaryStreamReader &Reader, uint16_t &ID,
 }
 
 Error ResourceEntryRef::loadNext() {
-  uint32_t DataSize;
-  RETURN_IF_ERROR(Reader.readInteger(DataSize));
-  uint32_t HeaderSize;
-  RETURN_IF_ERROR(Reader.readInteger(HeaderSize));
+  const WinResHeaderPrefix *Prefix;
+  RETURN_IF_ERROR(Reader.readObject(Prefix));
 
-  if (HeaderSize < MIN_HEADER_SIZE)
+  if (Prefix->HeaderSize < MIN_HEADER_SIZE)
     return make_error<GenericBinaryError>("Header size is too small.",
                                           object_error::parse_failed);
 
@@ -118,13 +112,13 @@ Error ResourceEntryRef::loadNext() {
 
   RETURN_IF_ERROR(readStringOrId(Reader, NameID, Name, IsStringName));
 
-  RETURN_IF_ERROR(Reader.padToAlignment(sizeof(uint32_t)));
+  RETURN_IF_ERROR(Reader.padToAlignment(WIN_RES_HEADER_ALIGNMENT));
 
   RETURN_IF_ERROR(Reader.readObject(Suffix));
 
-  RETURN_IF_ERROR(Reader.readArray(Data, DataSize));
+  RETURN_IF_ERROR(Reader.readArray(Data, Prefix->DataSize));
 
-  RETURN_IF_ERROR(Reader.padToAlignment(sizeof(uint32_t)));
+  RETURN_IF_ERROR(Reader.padToAlignment(WIN_RES_DATA_ALIGNMENT));
 
   return Error::success();
 }
@@ -468,8 +462,6 @@ void WindowsResourceCOFFWriter::writeFirstSectionHeader() {
   SectionOneHeader->PointerToLinenumbers = 0;
   SectionOneHeader->NumberOfRelocations = Data.size();
   SectionOneHeader->NumberOfLinenumbers = 0;
-  SectionOneHeader->Characteristics = COFF::IMAGE_SCN_ALIGN_1BYTES;
-  SectionOneHeader->Characteristics += COFF::IMAGE_SCN_CNT_INITIALIZED_DATA;
   SectionOneHeader->Characteristics += COFF::IMAGE_SCN_CNT_INITIALIZED_DATA;
   SectionOneHeader->Characteristics += COFF::IMAGE_SCN_MEM_READ;
 }

unittests/BinaryFormat/TestFileMagic.cpp

@@ -76,7 +76,8 @@ const char macho_dsym_companion[] =
     "\xfe\xed\xfa\xce........\x00\x00\x00\x0a............";
 const char macho_kext_bundle[] =
     "\xfe\xed\xfa\xce........\x00\x00\x00\x0b............";
-const char windows_resource[] = "\x00\x00\x00\x00\x020\x00\x00\x00\xff";
+const char windows_resource[] =
+    "\x00\x00\x00\x00\x020\x00\x00\x00\xff\xff\x00\x00\xff\xff\x00\x00";
 const char macho_dynamically_linked_shared_lib_stub[] =
     "\xfe\xed\xfa\xce........\x00\x00\x00\x09............";