cppcoro/include/cppcoro/read_only_file.hpp
Lewis Baker a34527617d Remove io_context and just use io_service& directly.
Added io_work_scope RAII class to help with scoped lifetime of
io_service event loop.

Having io_context always increment the ref-count of active I/O
operations whenever passed by-value to a function seems like
unnecessary atomic operations when compared to selected usages of
io_work_scope which generally only need creation for top-level
operations.
2017-06-25 22:03:46 +09:30

59 lines
1.7 KiB
C++

///////////////////////////////////////////////////////////////////////////////
// Copyright (c) Lewis Baker
// Licenced under MIT license. See LICENSE.txt for details.
///////////////////////////////////////////////////////////////////////////////
#ifndef CPPCORO_READ_ONLY_FILE_HPP_INCLUDED
#define CPPCORO_READ_ONLY_FILE_HPP_INCLUDED
#include <cppcoro/readable_file.hpp>
#include <cppcoro/file_share_mode.hpp>
#include <cppcoro/file_buffering_mode.hpp>
#include <experimental/filesystem>
namespace cppcoro
{
class read_only_file : public readable_file
{
public:
/// Open a file for read-only access.
///
/// \param ioContext
/// The I/O context to use when dispatching I/O completion events.
/// When asynchronous read operations on this file complete the
/// completion events will be dispatched to an I/O thread associated
/// with the I/O context.
///
/// \param path
/// Path of the file to open.
///
/// \param shareMode
/// Specifies the access to be allowed on the file concurrently with this file access.
///
/// \param bufferingMode
/// Specifies the modes/hints to provide to the OS that affects the behaviour
/// of its file buffering.
///
/// \return
/// An object that can be used to read from the file.
///
/// \throw std::system_error
/// If the file could not be opened for read.
[[nodiscard]]
static read_only_file open(
io_service& ioService,
const std::experimental::filesystem::path& path,
file_share_mode shareMode = file_share_mode::read,
file_buffering_mode bufferingMode = file_buffering_mode::default_);
protected:
#if CPPCORO_OS_WINNT
read_only_file(detail::win32::safe_handle&& fileHandle) noexcept;
#endif
};
}
#endif