Move the mount to its own module

src/alma.rs

@@ -0,0 +1,45 @@
+use super::block::BlockDevice;
+use super::error::{Error, ErrorKind};
+use super::mountstack::{Filesystem, MountStack};
+use failure::ResultExt;
+use log::info;
+use std::fs;
+use std::path::{Path, PathBuf};
+
+pub struct ALMA {
+    block: BlockDevice,
+}
+
+impl ALMA {
+    pub fn new(block: BlockDevice) -> Self {
+        Self { block }
+    }
+
+    pub fn mount<'a>(&self, path: &'a Path) -> Result<MountStack<'a>, Error> {
+        let mut mount_stack = MountStack::new();
+
+        info!("Mounting filesystems to {}", path.display());
+        mount_stack
+            .mount(
+                &PathBuf::from(&self.block.partition_device_path(3)?),
+                path,
+                Filesystem::Btrfs,
+                None,
+            ).context(ErrorKind::Mounting)?;
+
+        let boot_point = path.join("boot");
+        if !boot_point.exists() {
+            fs::create_dir(&boot_point).context(ErrorKind::CreateBoot)?;
+        }
+
+        mount_stack
+            .mount(
+                &self.block.partition_device_path(2)?,
+                boot_point,
+                Filesystem::Vfat,
+                None,
+            ).context(ErrorKind::Mounting)?;
+
+        Ok(mount_stack)
+    }
+}

src/main.rs

@@ -7,16 +7,17 @@ extern crate tempfile;
 extern crate which;
 use nix::sys::signal;
 
+mod alma;
 mod block;
 mod error;
 mod mountstack;
 mod process;
 mod tool;
 
+use alma::ALMA;
 use error::*;
 use failure::{Fail, ResultExt};
 use log::{debug, error, info, warn};
-use mountstack::{Filesystem, MountStack};
 use process::CommandExt;
 use simplelog::*;
 use std::fs;
@@ -91,8 +92,7 @@ fn create(command: CreateCommand) -> Result<(), Error> {
     let block_device = block::BlockDevice::from_path(command.block_device)?;
 
     let mount_point = tempdir().context(ErrorKind::TmpDirError)?;
-    let boot_point = mount_point.path().join("boot");
-    let mut mount_stack = MountStack::new();
+
     let disk_path = block_device.device_path();
 
     info!("Partitioning the block device");
@@ -128,20 +128,8 @@ fn create(command: CreateCommand) -> Result<(), Error> {
         .arg(&root_partition)
         .run(ErrorKind::Formatting)?;
 
-    info!("Mounting filesystems to {}", mount_point.path().display());
-    mount_stack
-        .mount(
-            &PathBuf::from(&root_partition),
-            &mount_point.path(),
-            Filesystem::Btrfs,
-            None,
-        ).context(ErrorKind::Mounting)?;
-
-    fs::create_dir(&boot_point).context(ErrorKind::CreateBoot)?;
-
-    mount_stack
-        .mount(&boot_partition, &boot_point, Filesystem::Vfat, None)
-        .context(ErrorKind::Mounting)?;
+    let alma = ALMA::new(block_device);
+    let mut mount_stack = alma.mount(mount_point.path())?;
 
     info!("Bootstrapping system");
     pacstrap
@@ -218,23 +206,8 @@ fn chroot(command: ChrootCommand) -> Result<(), Error> {
     let block_device = block::BlockDevice::from_path(command.block_device)?;
 
     let mount_point = tempdir().context(ErrorKind::TmpDirError)?;
-    let boot_point = mount_point.path().join("boot");
-    let mut mount_stack = MountStack::new();
-
-    info!("Mounting filesystems to {}", mount_point.path().display());
-    let root_partition = block_device.partition_device_path(3)?;
-    mount_stack
-        .mount(
-            &root_partition,
-            &mount_point.path(),
-            Filesystem::Btrfs,
-            None,
-        ).context(ErrorKind::Mounting)?;
-
-    let boot_partition = block_device.partition_device_path(2)?;
-    mount_stack
-        .mount(&boot_partition, &boot_point, Filesystem::Vfat, None)
-        .context(ErrorKind::Mounting)?;
+    let alma = ALMA::new(block_device);
+    let mut mount_stack = alma.mount(mount_point.path())?;
 
     arch_chroot
         .execute()
@@ -242,6 +215,8 @@ fn chroot(command: ChrootCommand) -> Result<(), Error> {
         .run(ErrorKind::Interactive)?;
 
     info!("Unmounting filesystems");
+    mount_stack.umount()?;
+
     Ok(())
 }
 

src/mountstack.rs

@@ -3,6 +3,7 @@ use failure::Fail;
 use log::{debug, warn};
 use nix;
 use nix::mount::{mount, umount, MsFlags};
+use std::borrow::Cow;
 use std::path::Path;
 
 #[derive(Debug)]
@@ -21,7 +22,7 @@ impl Filesystem {
 }
 
 pub struct MountStack<'a> {
-    targets: Vec<&'a Path>,
+    targets: Vec<Cow<'a, Path>>,
 }
 
 impl<'a> MountStack<'a> {
@@ -32,17 +33,19 @@ impl<'a> MountStack<'a> {
     }
 
     #[must_use]
-    pub fn mount(
+    pub fn mount<T: Into<Cow<'a, Path>>>(
         &mut self,
         source: &Path,
-        target: &'a Path,
+        target: T,
         filesystem: Filesystem,
         options: Option<&str>,
     ) -> nix::Result<()> {
+        let target = target.into();
+
         debug!("Mounting {:?} ({:?}) to {:?}", source, filesystem, target);
         mount(
             Some(source),
-            target,
+            target.as_ref(),
             Some(filesystem.to_type()),
             MsFlags::empty(),
             options,
@@ -56,7 +59,7 @@ impl<'a> MountStack<'a> {
 
         while let Some(target) = self.targets.pop() {
             debug!("Unmounting {}", target.display());
-            if let Err(e) = umount(target) {
+            if let Err(e) = umount(target.as_ref()) {
                 warn!("Unable to umount {}: {}", target.display(), e);
                 result = Err(Error::from(e.context(ErrorKind::UmountFailure)));
             };