src/tint/utils/bytes/buffer_writer.h

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#ifndef SRC_TINT_UTILS_BYTES_BUFFER_WRITER_H_
#define SRC_TINT_UTILS_BYTES_BUFFER_WRITER_H_

#include <stdint.h>

#include "src/tint/utils/bytes/writer.h"

namespace tint::bytes {

/// BufferWriter is an implementation of the Writer interface backed by a buffer.
template <size_t N>
class BufferWriter final : public Writer {
  public:
    /// @copydoc Writer::Write
    Result<SuccessType> Write(const std::byte* in, size_t count) override {
        size_t at = buffer.Length();
        buffer.Resize(at + count);
        memcpy(&buffer[at], in, count);
        return Success;
    }

    /// @returns the buffer content as a string view
    std::string_view BufferString() const {
        if (buffer.IsEmpty()) {
            return "";
        }
        auto* data = reinterpret_cast<const char*>(&buffer[0]);
        static_assert(sizeof(std::byte) == sizeof(char), "length needs calculation");
        return std::string_view(data, buffer.Length());
    }

    /// The buffer holding the written data
    Vector<std::byte, N> buffer;
};

/// Deduction guide for BufferWriter
BufferWriter() -> BufferWriter<32>;

}  // namespace tint::bytes

#endif  // SRC_TINT_UTILS_BYTES_BUFFER_WRITER_H_