bitrust 0.1.0

A Rust implementation of Bitcask, usable as a binary or a library.
Documentation 
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use std::fs;
use std::fs::OpenOptions;
use std::io::{self, Write};
use std::path::{Path, PathBuf};
use std::process;

#[derive(Debug)]
pub struct LockFile {
  path: PathBuf,
}

impl LockFile {
  pub fn new<P>(
    path: P,
    lockfile_contents: Option<&[u8]>,
  ) -> io::Result<LockFile>
  where
    P: AsRef<Path>,
  {
    {
      // create_new() translates to O_EXCL|O_CREAT being specified to the
      // underlying open() syscall on *nix (and CREATE_NEW to the
      // CreateFileW Windows API), which means that the call is successful
      // only if it is the one which created the file.
      let mut file = OpenOptions::new()
        .write(true)
        .create_new(true)
        .open(path.as_ref())?;
      if let Some(contents) = lockfile_contents {
        file.write_all(contents)?;
      }
    }
    debug!(
      "Successfully wrote lockfile {:?}, pid: {}",
      path.as_ref(),
      process::id()
    );
    // By this time the file we created is closed, and we are sure that
    // we are the one who created it.
    Ok(LockFile {
      path: path.as_ref().to_path_buf(),
    })
  }
}

impl Drop for LockFile {
  fn drop(&mut self) {
    debug!("Removing lockfile {:?}, pid: {}", &self.path, process::id());
    fs::remove_file(&self.path).unwrap();
  }
}