[BUG] LruEntry uninitialized, which is invalid

[dollarkillerx]

• bitcask master
• cargo 1.50.0 (f04e7fab7 2021-02-04)
• rustc 1.50.0 (cb75ad5db 2021-02-10)

run demo:

use bitcask;
use bytesize::ByteSize;

fn main() {
    let options = bitcask::Options {
        base_dir: std::path::PathBuf::from("./db1"),
        data_file_limit: ByteSize::mb(10).as_u64(),
    };

    let db = bitcask::new(options);
    if let Err(err_msg) = db {
        println!("{}", err_msg);
        std::process::exit(1);
    }
    let mut db = db.unwrap();

    for n in 0..1000 {
        let name = format!("Peter Nr. {}", n);
        let key = format!("name:{}", n);

        db.write(key.as_bytes(), name.as_bytes()).unwrap();
    }

    db.close().unwrap();
}

error report：

thread 'main' panicked at 'attempted to leave type `database::lru::LruEntry<u128, datafile::DataFile>` uninitialized, which is invalid', /home/xx/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:659:9
stack backtrace:
   0: rust_begin_unwind
             at /rustc/cb75ad5db02783e8b0222fee363c5f63f7e2cf5b/library/std/src/panicking.rs:493:5
   1: core::panicking::panic_fmt
             at /rustc/cb75ad5db02783e8b0222fee363c5f63f7e2cf5b/library/core/src/panicking.rs:92:14
   2: core::panicking::panic
             at /rustc/cb75ad5db02783e8b0222fee363c5f63f7e2cf5b/library/core/src/panicking.rs:50:5
   3: core::mem::uninitialized
             at /home/xx/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:659:9
   4: lru::LruCache<K,V,S>::construct
             at /home/xx/.cargo/registry/src/github.com-1ecc6299db9ec823/lru-0.1.17/src/lib.rs:216:51
   5: lru::LruCache<K,V>::new
             at /home/xx/.cargo/registry/src/github.com-1ecc6299db9ec823/lru-0.1.17/src/lib.rs:173:9
   6: bitcask::database::new
             at /home/xx/.cargo/git/checkouts/bitcask-ef3cb47bcd03a3bd/f218892/src/database.rs:75:27
   7: bitcask_rs::main
             at ./src/main.rs:10:14
   8: core::ops::function::FnOnce::call_once
             at /home/xx/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ops/function.rs:227:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

[dragonquest]

@dollarkillerx Sorry for getting back to you late, and THANK YOU very much for reporting this error. I will have a look when I have some free time. Feel free to send a pull request.

[papdpcpd]

this problem from lru :https://crates.io/crates/lru
use the latest version to fix this problem

....
# lru = "0.1.17"
lru = "0.6.5"
....