alma/src/storage/storage_device.rs
2019-06-17 20:34:34 +03:00

91 lines
2.5 KiB
Rust

use super::markers::{BlockDevice, Origin};
use super::partition::Partition;
use crate::error::{Error, ErrorKind};
use failure::ResultExt;
use log::debug;
use std::fs::read_to_string;
use std::marker::PhantomData;
use std::path::{Path, PathBuf};
#[derive(Debug)]
pub struct StorageDevice<'a> {
name: String,
path: PathBuf,
origin: PhantomData<&'a Origin>,
}
impl<'a> StorageDevice<'a> {
pub fn from_path(path: &'a Path) -> Result<Self, Error> {
let real_path = path.canonicalize().context(ErrorKind::DeviceQuery)?;
let device_name = real_path
.file_name()
.and_then(|s| s.to_str())
.map(String::from)
.ok_or_else(|| Error::from(ErrorKind::InvalidDeviceName))?;
debug!(
"path: {:?}, real path: {:?}, device name: {:?}",
path, real_path, device_name
);
drop(path);
let _self = Self {
name: device_name,
path: real_path,
origin: PhantomData,
};
if !(_self.is_removable_device()? || _self.is_loop_device()) {
return Err(ErrorKind::DangerousDevice)?;
}
Ok(_self)
}
fn sys_path(&self) -> PathBuf {
let mut path = PathBuf::from("/sys/block");
path.push(self.name.clone());
path
}
fn is_removable_device(&self) -> Result<bool, Error> {
let mut path = self.sys_path();
path.push("removable");
debug!("Reading: {:?}", path);
let result = read_to_string(&path).context(ErrorKind::DeviceQuery)?;
debug!("{:?} -> {}", path, result);
Ok(result == "1\n")
}
fn is_loop_device(&self) -> bool {
let mut path = self.sys_path();
path.push("loop");
path.exists()
}
pub fn get_partition(&self, index: u8) -> Result<Partition, Error> {
let name = if self.name.chars().rev().next().unwrap().is_digit(10) {
format!("{}p{}", self.name, index)
} else {
format!("{}{}", self.name, index)
};
let mut path = PathBuf::from("/dev");
path.push(name);
debug!("Partition {} for {} is in {:?}", index, self.name, path);
if !path.exists() {
return Err(ErrorKind::NoSuchPartition(index).into());
}
Ok(Partition::new::<Self>(path))
}
}
impl<'a> BlockDevice for StorageDevice<'a> {
fn path(&self) -> &Path {
&self.path
}
}
impl<'a> Origin for StorageDevice<'a> {}