ceph-rust 0.1.17

// Copyright 2017 LambdaStack All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// 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.

#![cfg(target_os = "linux")]

use std::str;
use std::io::{Read, Write, Cursor};
use std::os::unix::net::UnixStream;
use std::net::Shutdown;

use error::{RadosError, RadosResult};
use byteorder::{BigEndian, ReadBytesExt};

/// This is a helper function that builds a raw command from the actual command. You just pass
/// in a command like "help". The returned `String` will be a JSON String.
pub fn admin_socket_command(cmd: &str, socket: &str) -> RadosResult<String> {
    let raw_cmd = format!("{{\"{}\": \"{}\"}}", "prefix", cmd);
    admin_socket_raw_command(&raw_cmd, socket)
}

/// This function supports a raw command in the format of something like: `{"prefix": "help"}`.
/// The returned `String` will be a JSON String.
#[allow(unused_variables)]
pub fn admin_socket_raw_command(cmd: &str, socket: &str) -> RadosResult<String> {
    let mut output = String::new();
    let mut buffer = vec![0;4];  // Should return 4 bytes with size or indicator.
    let cmd = &format!("{}\0", cmd);  // Terminator so don't add one to commands.

    let mut stream = try!(UnixStream::connect(socket));
    let wb = try!(stream.write(cmd.as_bytes()));
    let ret_val = try!(stream.read(&mut buffer));
    if ret_val < 4 {
        try!(stream.shutdown(Shutdown::Both));
        return Err(RadosError::new("Admin socket: Invalid command or socket did not return any data".to_string()));
    }
    // The first 4 bytes are Big Endian unsigned int
    let mut rdr = Cursor::new(buffer);
    let len = rdr.read_u32::<BigEndian>().unwrap();
    // Not currently using the len but may...

    let rb = try!(stream.read_to_string(&mut output));
    try!(stream.shutdown(Shutdown::Both));

    Ok(output)
}