ladybird/Userland/Libraries/LibCore/IODevice.h
Gunnar Beutner fbfd0ed5ab LibCore: Open files with O_CLOEXEC by default
This changes Core::File::open() to specify O_CLOEXEC by default
so that we don't leak file descriptors into child processes. The
new behavior can be overriden by specifying OpenMode::KeepOnExec.
2021-05-17 13:32:19 +02:00

116 lines
2.7 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/EnumBits.h>
#include <AK/Forward.h>
#include <LibCore/Object.h>
namespace Core {
// This is not necessarily a valid iterator in all contexts,
// if we had concepts, this would be InputIterator, not Copyable, Movable.
class LineIterator {
AK_MAKE_NONCOPYABLE(LineIterator);
public:
explicit LineIterator(IODevice&, bool is_end = false);
bool operator==(const LineIterator& other) const { return &other == this || (at_end() && other.is_end()) || (other.at_end() && is_end()); }
bool is_end() const { return m_is_end; }
bool at_end() const;
LineIterator& operator++();
StringView operator*() const { return m_buffer; }
private:
NonnullRefPtr<IODevice> m_device;
bool m_is_end { false };
String m_buffer;
};
enum class OpenMode : unsigned {
NotOpen = 0,
ReadOnly = 1,
WriteOnly = 2,
ReadWrite = 3,
Append = 4,
Truncate = 8,
MustBeNew = 16,
KeepOnExec = 32,
};
enum class SeekMode {
SetPosition,
FromCurrentPosition,
FromEndPosition,
};
AK_ENUM_BITWISE_OPERATORS(OpenMode)
class IODevice : public Object {
C_OBJECT_ABSTRACT(IODevice)
public:
virtual ~IODevice() override;
int fd() const { return m_fd; }
OpenMode mode() const { return m_mode; }
bool is_open() const { return m_mode != OpenMode::NotOpen; }
bool eof() const { return m_eof; }
int error() const { return m_error; }
const char* error_string() const;
bool has_error() const { return m_error != 0; }
int read(u8* buffer, int length);
ByteBuffer read(size_t max_size);
ByteBuffer read_all();
String read_line(size_t max_size = 16384);
bool write(const u8*, int size);
bool write(const StringView&);
bool truncate(off_t);
bool can_read_line() const;
bool can_read() const;
bool seek(i64, SeekMode = SeekMode::SetPosition, off_t* = nullptr);
virtual bool open(OpenMode) = 0;
virtual bool close();
LineIterator line_begin() & { return LineIterator(*this); }
LineIterator line_end() { return LineIterator(*this, true); }
protected:
explicit IODevice(Object* parent = nullptr);
void set_fd(int);
void set_mode(OpenMode mode) { m_mode = mode; }
void set_error(int error) const { m_error = error; }
void set_eof(bool eof) const { m_eof = eof; }
virtual void did_update_fd(int) { }
private:
bool populate_read_buffer() const;
bool can_read_from_fd() const;
int m_fd { -1 };
OpenMode m_mode { OpenMode::NotOpen };
mutable int m_error { 0 };
mutable bool m_eof { false };
mutable Vector<u8> m_buffered_data;
};
}