src/tint/utils/bytes/buffer_reader.h

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#ifndef SRC_TINT_UTILS_BYTES_BUFFER_READER_H_
#define SRC_TINT_UTILS_BYTES_BUFFER_READER_H_

#include <algorithm>
#include <string>

#include "src/tint/utils/bytes/reader.h"
#include "src/tint/utils/ice/ice.h"

namespace tint::bytes {

/// BufferReader is an implementation of the Reader interface backed by a buffer.
class BufferReader final : public Reader {
  public:
    // Destructor
    ~BufferReader() override;

    /// Constructor
    /// @param data the data to read from
    /// @param size the number of bytes in the buffer
    BufferReader(const std::byte* data, size_t size) : data_(data), bytes_remaining_(size) {
        TINT_ASSERT(data);
    }

    /// Constructor
    /// @param string the string to read from
    explicit BufferReader(std::string_view string)
        : data_(reinterpret_cast<const std::byte*>(string.data())),
          bytes_remaining_(string.length()) {}

    /// Constructor
    /// @param slice the byte slice to read from
    explicit BufferReader(Slice<const std::byte> slice)
        : data_(slice.data), bytes_remaining_(slice.len) {
        TINT_ASSERT(slice.data);
    }

    /// @copydoc Reader::Read
    size_t Read(std::byte* out, size_t count) override;

    /// @copydoc Reader::IsEOF
    bool IsEOF() const override;

  private:
    /// The data to read from
    const std::byte* data_ = nullptr;

    /// The number of bytes remaining
    size_t bytes_remaining_ = 0;
};

}  // namespace tint::bytes

#endif  // SRC_TINT_UTILS_BYTES_BUFFER_READER_H_