ladybird/Userland/Libraries/LibCore/MemoryStream.h

50 lines
1.4 KiB
C++

/*
* Copyright (c) 2021, kleines Filmröllchen <filmroellchen@serenityos.org>.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Error.h>
#include <AK/NonnullOwnPtr.h>
#include <AK/OwnPtr.h>
#include <AK/Span.h>
#include <AK/TypedTransfer.h>
#include <LibCore/Stream.h>
namespace Core::Stream {
/// A stream class that allows for reading/writing on a preallocated memory area
/// using a single read/write head.
class FixedMemoryStream final : public SeekableStream {
public:
static ErrorOr<NonnullOwnPtr<FixedMemoryStream>> construct(Bytes bytes);
static ErrorOr<NonnullOwnPtr<FixedMemoryStream>> construct(ReadonlyBytes bytes);
virtual bool is_eof() const override;
virtual bool is_open() const override;
virtual void close() override;
virtual ErrorOr<void> truncate(off_t) override;
virtual ErrorOr<Bytes> read(Bytes bytes) override;
virtual ErrorOr<off_t> seek(i64 offset, SeekMode seek_mode = SeekMode::SetPosition) override;
virtual ErrorOr<size_t> write(ReadonlyBytes bytes) override;
virtual ErrorOr<void> write_entire_buffer(ReadonlyBytes bytes) override;
Bytes bytes();
ReadonlyBytes bytes() const;
size_t offset() const;
size_t remaining() const;
private:
explicit FixedMemoryStream(Bytes bytes);
explicit FixedMemoryStream(ReadonlyBytes bytes);
Bytes m_bytes;
size_t m_offset { 0 };
bool m_writing_enabled { true };
};
}