44e35ef545
Preallocate disk blocks in advance of writing. Reviewed-by: Pekka Enberg <penberg@cloudius-systems.com>
61 lines
2.2 KiB
C++
61 lines
2.2 KiB
C++
/*
|
|
* This file is open source software, licensed to you under the terms
|
|
* of the Apache License, Version 2.0 (the "License"). See the NOTICE file
|
|
* distributed with this work for additional information regarding copyright
|
|
* ownership. You may not use this file except in compliance with the License.
|
|
*
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing,
|
|
* software distributed under the License is distributed on an
|
|
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
|
|
* KIND, either express or implied. See the License for the
|
|
* specific language governing permissions and limitations
|
|
* under the License.
|
|
*/
|
|
/*
|
|
* Copyright (C) 2015 Cloudius Systems, Ltd.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
// File <-> streams adapters
|
|
//
|
|
// Seastar files are block-based due to the reliance on DMA - you must read
|
|
// on sector boundaries. The adapters in this file provide a byte stream
|
|
// interface to files, while retaining the zero-copy characteristics of
|
|
// seastar files.
|
|
|
|
#include "file.hh"
|
|
#include "iostream.hh"
|
|
#include "shared_ptr.hh"
|
|
|
|
// Create an input_stream for reading starting at a given position of the
|
|
// given file. Multiple fibers of execution (continuations) may safely open
|
|
// multiple input streams concurrently for the same file.
|
|
input_stream<char> make_file_input_stream(
|
|
lw_shared_ptr<file> file, uint64_t offset = 0,
|
|
uint64_t buffer_size = 8192);
|
|
|
|
struct file_output_stream_options {
|
|
unsigned buffer_size = 8192;
|
|
unsigned preallocation_size = 1024*1024; // 1MB
|
|
};
|
|
|
|
// Create an output_stream for writing starting at the position zero of a
|
|
// newly created file.
|
|
// NOTE: flush() should be the last thing to be called on a file output stream.
|
|
output_stream<char> make_file_output_stream(
|
|
lw_shared_ptr<file> file,
|
|
uint64_t buffer_size = 8192);
|
|
|
|
/// Create an output_stream for writing starting at the position zero of a
|
|
/// newly created file.
|
|
/// NOTE: flush() should be the last thing to be called on a file output stream.
|
|
output_stream<char> make_file_output_stream(
|
|
lw_shared_ptr<file> file,
|
|
file_output_stream_options options);
|
|
|