ladybird/AK/Buffered.h
Lenny Maiorani 7d8a9bdb1e AK: Cleanup missing includes and #ifdef evaluation
Problem:
- Several files have missing includes. This results in complaints from
  `clang-tidy`.
- `#ifdef` is followed by `#elif <value>` which evaluates to `0`.

Solution:
- Add missing includes.
- Change to `#elif defined(<value>)`.
2020-11-22 11:35:53 +01:00

217 lines
6.4 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/Noncopyable.h>
#include <AK/Span.h>
#include <AK/StdLibExtras.h>
#include <AK/Stream.h>
#include <AK/Types.h>
#include <AK/kmalloc.h>
namespace AK {
// FIXME: Implement Buffered<T> for DuplexStream.
template<typename StreamType, size_t Size = 4096, typename = void>
class Buffered;
template<typename StreamType, size_t Size>
class Buffered<StreamType, Size, typename EnableIf<IsBaseOf<InputStream, StreamType>::value>::Type> final : public InputStream {
AK_MAKE_NONCOPYABLE(Buffered);
public:
template<typename... Parameters>
explicit Buffered(Parameters&&... parameters)
: m_stream(forward<Parameters>(parameters)...)
{
}
Buffered(Buffered&& other)
: m_stream(move(other.m_stream))
{
other.buffer().copy_to(buffer());
m_buffered = exchange(other.m_buffered, 0);
}
bool has_recoverable_error() const override { return m_stream.has_recoverable_error(); }
bool has_fatal_error() const override { return m_stream.has_fatal_error(); }
bool has_any_error() const override { return m_stream.has_any_error(); }
bool handle_recoverable_error() override { return m_stream.handle_recoverable_error(); }
bool handle_fatal_error() override { return m_stream.handle_fatal_error(); }
bool handle_any_error() override { return m_stream.handle_any_error(); }
void set_recoverable_error() const override { return m_stream.set_recoverable_error(); }
void set_fatal_error() const override { return m_stream.set_fatal_error(); }
size_t read(Bytes bytes) override
{
if (has_any_error())
return 0;
auto nread = buffer().trim(m_buffered).copy_trimmed_to(bytes);
m_buffered -= nread;
buffer().slice(nread, m_buffered).copy_to(buffer());
if (nread < bytes.size()) {
m_buffered = m_stream.read(buffer());
if (m_buffered == 0)
return nread;
nread += read(bytes.slice(nread));
}
return nread;
}
bool read_or_error(Bytes bytes) override
{
if (read(bytes) < bytes.size()) {
set_fatal_error();
return false;
}
return true;
}
bool unreliable_eof() const override { return m_buffered == 0 && m_stream.unreliable_eof(); }
bool eof() const
{
if (m_buffered > 0)
return false;
m_buffered = m_stream.read(buffer());
return m_buffered == 0;
}
bool discard_or_error(size_t count) override
{
size_t ndiscarded = 0;
while (ndiscarded < count) {
u8 dummy[Size];
if (!read_or_error({ dummy, min(Size, count - ndiscarded) }))
return false;
ndiscarded += min(Size, count - ndiscarded);
}
return true;
}
private:
Bytes buffer() const { return { m_buffer, Size }; }
mutable StreamType m_stream;
mutable u8 m_buffer[Size];
mutable size_t m_buffered { 0 };
};
template<typename StreamType, size_t Size>
class Buffered<StreamType, Size, typename EnableIf<IsBaseOf<OutputStream, StreamType>::value>::Type> final : public OutputStream {
AK_MAKE_NONCOPYABLE(Buffered);
public:
template<typename... Parameters>
explicit Buffered(Parameters&&... parameters)
: m_stream(forward<Parameters>(parameters)...)
{
}
Buffered(Buffered&& other)
: m_stream(move(other.m_stream))
{
other.buffer().copy_to(buffer());
m_buffered = exchange(other.m_buffered, 0);
}
~Buffered()
{
if (m_buffered > 0)
flush();
}
bool has_recoverable_error() const override { return m_stream.has_recoverable_error(); }
bool has_fatal_error() const override { return m_stream.has_fatal_error(); }
bool has_any_error() const override { return m_stream.has_any_error(); }
bool handle_recoverable_error() override { return m_stream.handle_recoverable_error(); }
bool handle_fatal_error() override { return m_stream.handle_fatal_error(); }
bool handle_any_error() override { return m_stream.handle_any_error(); }
void set_recoverable_error() const override { return m_stream.set_recoverable_error(); }
void set_fatal_error() const override { return m_stream.set_fatal_error(); }
size_t write(ReadonlyBytes bytes) override
{
if (has_any_error())
return 0;
auto nwritten = bytes.copy_trimmed_to(buffer().slice(m_buffered));
m_buffered += nwritten;
if (m_buffered == Size) {
flush();
if (bytes.size() - nwritten >= Size)
nwritten += m_stream.write(bytes.slice(nwritten));
nwritten += write(bytes.slice(nwritten));
}
return nwritten;
}
bool write_or_error(ReadonlyBytes bytes) override
{
write(bytes);
return true;
}
void flush()
{
m_stream.write_or_error({ m_buffer, m_buffered });
m_buffered = 0;
}
private:
Bytes buffer() { return { m_buffer, Size }; }
StreamType m_stream;
u8 m_buffer[Size];
size_t m_buffered { 0 };
};
}
using AK::Buffered;