Mercurial > lbo > hg > leveldb-rs
view src/env.rs @ 371:f8b1e35370a7
Meta: Update hgignore to ignore leveldb test files.
author | Lewin Bormann <lbo@spheniscida.de> |
---|---|
date | Sun, 08 Oct 2017 13:53:33 +0200 |
parents | 9a2f35bb13d6 |
children | 24e076b4ad21 |
line wrap: on
line source
//! An `env` is an abstraction layer that allows the database to run both on different platforms as //! well as persisting data on disk or in memory. use error::Result; use std::io::prelude::*; use std::fs::File; use std::os::unix::fs::FileExt; use std::path::Path; pub trait RandomAccess { fn read_at(&self, off: usize, dst: &mut [u8]) -> Result<usize>; } impl RandomAccess for File { fn read_at(&self, off: usize, dst: &mut [u8]) -> Result<usize> { Ok((self as &FileExt).read_at(dst, off as u64)?) } } pub struct FileLock { pub id: String, } pub trait Env { fn open_sequential_file(&self, &Path) -> Result<Box<Read>>; fn open_random_access_file(&self, &Path) -> Result<Box<RandomAccess>>; fn open_writable_file(&self, &Path) -> Result<Box<Write>>; fn open_appendable_file(&self, &Path) -> Result<Box<Write>>; fn exists(&self, &Path) -> Result<bool>; fn children(&self, &Path) -> Result<Vec<String>>; fn size_of(&self, &Path) -> Result<usize>; fn delete(&self, &Path) -> Result<()>; fn mkdir(&self, &Path) -> Result<()>; fn rmdir(&self, &Path) -> Result<()>; fn rename(&self, &Path, &Path) -> Result<()>; fn lock(&self, &Path) -> Result<FileLock>; fn unlock(&self, l: FileLock) -> Result<()>; fn new_logger(&self, &Path) -> Result<Logger>; fn micros(&self) -> u64; fn sleep_for(&self, micros: u32); } pub struct Logger { dst: Box<Write>, } impl Logger { pub fn new(w: Box<Write>) -> Logger { Logger { dst: w } } pub fn log(&mut self, message: &String) { let _ = self.dst.write(message.as_bytes()); let _ = self.dst.write("\n".as_bytes()); } } pub fn path_to_string(p: &Path) -> String { p.to_str().map(String::from).unwrap() } pub fn path_to_str(p: &Path) -> &str { p.to_str().unwrap() }