mini-fs

mini-fs 是应用程序层的一个可扩展的虚拟文件系统。

支持从本地文件系统以及Tar & Zip存档中读取。

[dependencies]
mini-fs = "0.2"

API示例展示

use mini_fs::prelude::*;
use mini_fs::{LocalFs, TarFs, MiniFs};

// Declare some file systems.
let local = LocalFs::pwd()?;
let tar = TarFs::open("archive.tar.gz")?;

// Mount them.
let mut fs = MiniFs::new()
    .mount("/data", local)
    .mount("/archived", tar);

// To open (read) files:
let file = fs.open("/data/example.gif")?;

覆盖文件系统

您可以使用元组合并多个文件系统，使它们共享相同的挂载点。这允许您在位置之间覆盖文件。

示例用例

• 具有默认回退的配置文件。
• 替换游戏中的资源（模组）。

let a = LocalFs::new("data/");
// |- example.txt

let b = TarFs::open("archive.tar.gz")?;
// |- example.txt
// |- hello.txt

let files = MiniFs::new().mount("/files", (a, b));

assert!(files.open("/files/example.txt").is_ok()); // this "example.txt" is from "a"
assert!(files.open("/files/hello.txt").is_ok());

请注意，如果您尝试首先在相同的挂载点下挂载 a，然后是 b，则第一个将被 b 遮盖。

可扩展的

您可能定义一个新的文件存储，以便您可以读取该crate不支持直接支持的存档格式中的文件。

您需要做的是

1. 定义两个类型：存储本身及其返回的文件类型。
2. 在第一个类型上实现 Store trait，并在第二个上实现 UserFile。

例如，假设您想实现一个基于Zip存档的文件存储（MyZip）（此crate已有实现，但让我们假设您想改进它）。

首先，定义存储和它将返回的文件类型。

use std::io;
use mini_fs::{Store, UserFile};

// This is the filesystem that will be mounted.
struct MyZip { /*...*/ }

// This example MyZip implementatin will return a slice of bytes for each
// entry in the archive. It is wrapped in a Cursor to enable IO later.
struct MyZipEntry(io::Cursor<Box<[u8]>>);

impl UserFile for MyZipEntry {}

在 MyZipEntry 上实现IO。

impl io::Read for MyZipEntry {
    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
        self.0.read(buf)
    }
}

impl io::Seek for MyZipEntry { /* skipped */ }

最后，在 MyZip 上实现 Store trait。

impl Store for MyZip {
    type File = MyZipEntry;
    
    fn open_path(&self, path: &Path) -> io::Result<MyZipEntry> {
        // Fetch file
        // ...
    }
}

就是这样。现在您可以为 MyZip 挂载并/或将其用作元组的一部分。

许可证

MIT License

Copyright (c) 2019 German Gomez Bajo

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.