core/fxcrt/mapped_data_bytes.h

// Copyright 2026 The PDFium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CORE_FXCRT_MAPPED_DATA_BYTES_H_
#define CORE_FXCRT_MAPPED_DATA_BYTES_H_

#include <stddef.h>
#include <stdint.h>

#include <memory>

#include "core/fxcrt/bytestring.h"
#include "core/fxcrt/span.h"

namespace fxcrt {

class MappedDataBytes {
 public:
  static std::unique_ptr<MappedDataBytes> Create(const ByteString& file_name);

  MappedDataBytes(const MappedDataBytes&) = delete;
  MappedDataBytes(MappedDataBytes&&) = delete;
  MappedDataBytes& operator=(const MappedDataBytes&) = delete;
  MappedDataBytes& operator=(MappedDataBytes&&) = delete;

  ~MappedDataBytes();

  bool empty() const { return mapping_.empty(); }
  size_t size() const { return mapping_.size(); }

  // Explicit access to data via span.
  pdfium::span<const uint8_t> span() const { return mapping_; }

 private:
  explicit MappedDataBytes(int fd);

  const int fd_;
  pdfium::span<const uint8_t> mapping_;
};

}  // namespace fxcrt

using fxcrt::MappedDataBytes;

#endif  // CORE_FXCRT_MAPPED_DATA_BYTES_H_