//===--- Serialization/PCHContainerOperations.h - PCH Containers --*- 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
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_CLANG_SERIALIZATION_PCHCONTAINEROPERATIONS_H
 
#define LLVM_CLANG_SERIALIZATION_PCHCONTAINEROPERATIONS_H
 
 
 
#include "clang/Basic/Module.h"
 
#include "llvm/ADT/SmallVector.h"
 
#include "llvm/ADT/StringMap.h"
 
#include "llvm/Support/MemoryBuffer.h"
 
#include <memory>
 
 
 
namespace llvm {
 
class raw_pwrite_stream;
 
}
 
 
 
namespace clang {
 
 
 
class ASTConsumer;
 
class CompilerInstance;
 
 
 
struct PCHBuffer {
 
  ASTFileSignature Signature;
 
  llvm::SmallVector<char, 0> Data;
 
  bool IsComplete;
 
};
 
 
 
/// This abstract interface provides operations for creating
 
/// containers for serialized ASTs (precompiled headers and clang
 
/// modules).
 
class PCHContainerWriter {
 
public:
 
  virtual ~PCHContainerWriter() = 0;
 
  virtual llvm::StringRef getFormat() const = 0;
 
 
 
  /// Return an ASTConsumer that can be chained with a
 
  /// PCHGenerator that produces a wrapper file format containing a
 
  /// serialized AST bitstream.
 
  virtual std::unique_ptr<ASTConsumer>
 
  CreatePCHContainerGenerator(CompilerInstance &CI,
 
                              const std::string &MainFileName,
 
                              const std::string &OutputFileName,
 
                              std::unique_ptr<llvm::raw_pwrite_stream> OS,
 
                              std::shared_ptr<PCHBuffer> Buffer) const = 0;
 
};
 
 
 
/// This abstract interface provides operations for unwrapping
 
/// containers for serialized ASTs (precompiled headers and clang
 
/// modules).
 
class PCHContainerReader {
 
public:
 
  virtual ~PCHContainerReader() = 0;
 
  /// Equivalent to the format passed to -fmodule-format=
 
  virtual llvm::StringRef getFormat() const = 0;
 
 
 
  /// Returns the serialized AST inside the PCH container Buffer.
 
  virtual llvm::StringRef ExtractPCH(llvm::MemoryBufferRef Buffer) const = 0;
 
};
 
 
 
/// Implements write operations for a raw pass-through PCH container.
 
class RawPCHContainerWriter : public PCHContainerWriter {
 
  llvm::StringRef getFormat() const override { return "raw"; }
 
 
 
  /// Return an ASTConsumer that can be chained with a
 
  /// PCHGenerator that writes the module to a flat file.
 
  std::unique_ptr<ASTConsumer>
 
  CreatePCHContainerGenerator(CompilerInstance &CI,
 
                              const std::string &MainFileName,
 
                              const std::string &OutputFileName,
 
                              std::unique_ptr<llvm::raw_pwrite_stream> OS,
 
                              std::shared_ptr<PCHBuffer> Buffer) const override;
 
};
 
 
 
/// Implements read operations for a raw pass-through PCH container.
 
class RawPCHContainerReader : public PCHContainerReader {
 
  llvm::StringRef getFormat() const override { return "raw"; }
 
 
 
  /// Simply returns the buffer contained in Buffer.
 
  llvm::StringRef ExtractPCH(llvm::MemoryBufferRef Buffer) const override;
 
};
 
 
 
/// A registry of PCHContainerWriter and -Reader objects for different formats.
 
class PCHContainerOperations {
 
  llvm::StringMap<std::unique_ptr<PCHContainerWriter>> Writers;
 
  llvm::StringMap<std::unique_ptr<PCHContainerReader>> Readers;
 
public:
 
  /// Automatically registers a RawPCHContainerWriter and
 
  /// RawPCHContainerReader.
 
  PCHContainerOperations();
 
  void registerWriter(std::unique_ptr<PCHContainerWriter> Writer) {
 
    Writers[Writer->getFormat()] = std::move(Writer);
 
  }
 
  void registerReader(std::unique_ptr<PCHContainerReader> Reader) {
 
    Readers[Reader->getFormat()] = std::move(Reader);
 
  }
 
  const PCHContainerWriter *getWriterOrNull(llvm::StringRef Format) {
 
    return Writers[Format].get();
 
  }
 
  const PCHContainerReader *getReaderOrNull(llvm::StringRef Format) {
 
    return Readers[Format].get();
 
  }
 
  const PCHContainerReader &getRawReader() {
 
    return *getReaderOrNull("raw");
 
  }
 
};
 
 
 
}
 
 
 
#endif