//===-- WindowsManifestMerger.h ---------------------------------*- C++-*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===---------------------------------------------------------------------===//
//
// This file provides a utility for merging Microsoft .manifest files.  These
// files are xml documents which contain meta-information about applications,
// such as whether or not admin access is required, system compatibility,
// versions, etc.  Part of the linking process of an executable may require
// merging several of these .manifest files using a tree-merge following
// specific rules.  Unfortunately, these rules are not documented well
// anywhere.  However, a careful investigation of the behavior of the original
// Microsoft Manifest Tool (mt.exe) revealed the rules of this merge.  As the
// saying goes, code is the best documentation, so please look below if you are
// interested in the exact merging requirements.
//
// Ref:
// https://msdn.microsoft.com/en-us/library/windows/desktop/aa374191(v=vs.85).aspx
//
//===---------------------------------------------------------------------===//

#ifndef LLVM_WINDOWSMANIFEST_WINDOWSMANIFESTMERGER_H
#define LLVM_WINDOWSMANIFEST_WINDOWSMANIFESTMERGER_H

#include "llvm/Support/Compiler.h"
#include "llvm/Support/Error.h"

namespace llvm {

class MemoryBuffer;
class MemoryBufferRef;

namespace windows_manifest {

LLVM_ABI bool isAvailable();

class LLVM_ABI WindowsManifestError
    : public ErrorInfo<WindowsManifestError, ECError> {
public:
  static char ID;
  WindowsManifestError(const Twine &Msg);
  void log(raw_ostream &OS) const override;

private:
  std::string Msg;
};

class WindowsManifestMerger {
public:
  LLVM_ABI WindowsManifestMerger();
  LLVM_ABI ~WindowsManifestMerger();
  LLVM_ABI Error merge(MemoryBufferRef Manifest);

  // Returns vector containing merged xml manifest, or uninitialized vector for
  // empty manifest.
  LLVM_ABI std::unique_ptr<MemoryBuffer> getMergedManifest();

private:
  class WindowsManifestMergerImpl;
  std::unique_ptr<WindowsManifestMergerImpl> Impl;
};

} // namespace windows_manifest
} // namespace llvm
#endif
