1 files changed, 97 insertions, 0 deletions
diff --git a/lib/Bitcode/Reader/ReaderWrappers.cpp b/lib/Bitcode/Reader/ReaderWrappers.cpp
new file mode 100644
index 0000000000..7f6a80953a
--- /dev/null
+++ b/lib/Bitcode/Reader/ReaderWrappers.cpp
@@ -0,0 +1,97 @@
+//===- ReaderWrappers.cpp - Parse bitcode from file or buffer -------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Chris Lattner and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements loading and parsing a bitcode file and parsing a
+// module from a memory buffer.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "BitcodeReader.h"
+#include "llvm/System/MappedFile.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// BitcodeFileReader - Read from an mmap'able file descriptor.
+
+namespace {
+  /// BitcodeFileReader - parses bitcode from a file.
+  ///
+  class BitcodeFileReader : public BitcodeReader {
+  private:
+    std::string Filename;
+    sys::MappedFile File;
+    
+    BitcodeFileReader(const BitcodeFileReader&); // DO NOT IMPLEMENT
+    void operator=(const BitcodeFileReader&); // DO NOT IMPLEMENT
+  public:
+    BitcodeFileReader(const std::string &FN) : Filename(FN) {}
+    bool Read(std::string *ErrMsg);
+    
+    void FreeState() {
+      BitcodeReader::FreeState();
+      File.close();
+    }
+  };
+}
+
+bool BitcodeFileReader::Read(std::string *ErrMsg) {
+  if (File.open(sys::Path(Filename), sys::MappedFile::READ_ACCESS, ErrMsg))
+    return true;
+  if (!File.map(ErrMsg)) {
+    File.close();
+    return true;
+  }
+  unsigned char *Buffer = reinterpret_cast<unsigned char*>(File.base());
+  if (!ParseBitcode(Buffer, File.size(), Filename))
+    return false;
+  if (ErrMsg) *ErrMsg = getErrorString();
+  return true;
+}
+
+
+
+//===----------------------------------------------------------------------===//
+// External interface
+//===----------------------------------------------------------------------===//
+
+/// getBitcodeModuleProvider - lazy function-at-a-time loading from a file.
+///
+ModuleProvider *llvm::getBitcodeModuleProvider(const std::string &Filename,
+                                               std::string *ErrMsg) {
+  if (Filename != std::string("-")) {
+    BitcodeFileReader *R = new BitcodeFileReader(Filename);
+    if (R->Read(ErrMsg)) {
+      delete R;
+      return 0;
+    }
+    return R;
+  }
+  
+  assert(0 && "FIXME: stdin reading unimp!");
+#if 0
+  // Read from stdin
+  BytecodeStdinReader *R = new BytecodeStdinReader();
+  if (R->Read(ErrMsg)) {
+    delete R;
+    return 0;
+  }
+  return R;
+#endif
+}
+
+/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
+/// If an error occurs, return null and fill in *ErrMsg if non-null.
+Module *llvm::ParseBitcodeFile(const std::string &Filename,std::string *ErrMsg){
+  ModuleProvider *MP = getBitcodeModuleProvider(Filename, ErrMsg);
+  if (!MP) return 0;
+  Module *M = MP->releaseModule(ErrMsg);
+  delete MP;
+  return M;
+}