Add prep_before_update() to remove duplicated lines

`prep_before_update()` is to initialize parent devices to prepare
the update

Author: HuijingHei

src/blockdev.rs

@@ -64,11 +64,11 @@ pub fn get_esp_partition(device: &str) -> Result<Option<String>> {
     Ok(None)
 }
 
-/// Find all ESP partitions on the devices with mountpoint boot
+/// Find all ESP partitions on the devices
 #[allow(dead_code)]
-pub fn find_colocated_esps<P: AsRef<Path>>(target_root: P) -> Result<Vec<String>> {
+pub fn find_colocated_esps() -> Result<Vec<String>> {
     // first, get the parent device
-    let devices = get_devices(&target_root).with_context(|| "while looking for colocated ESPs")?;
+    let devices = get_parent_devices();
 
     // now, look for all ESPs on those devices
     let mut esps = Vec::new();
@@ -95,12 +95,11 @@ pub fn get_bios_boot_partition(device: &str) -> Result<Option<String>> {
     Ok(None)
 }
 
-/// Find all bios_boot partitions on the devices with mountpoint boot
+/// Find all bios_boot partitions on the devices
 #[allow(dead_code)]
-pub fn find_colocated_bios_boot<P: AsRef<Path>>(target_root: P) -> Result<Vec<String>> {
+pub fn find_colocated_bios_boot() -> Result<Vec<String>> {
     // first, get the parent device
-    let devices =
-        get_devices(&target_root).with_context(|| "looking for colocated bios_boot parts")?;
+    let devices = get_parent_devices();
 
     // now, look for all bios_boot parts on those devices
     let mut bios_boots = Vec::new();

src/cli/bootupctl.rs

@@ -130,26 +130,14 @@ impl CtlCommand {
     /// Runner for `update` verb.
     fn run_update() -> Result<()> {
         ensure_running_in_systemd()?;
-        let sysroot = openat::Dir::open("/").context("Opening root dir")?;
-        let dest_fd = format!("/proc/self/fd/{}", sysroot.as_raw_fd());
-        let dest_root = std::fs::read_link(dest_fd)?;
-
-        let devices = crate::blockdev::get_devices(&dest_root)
-            .with_context(|| "while looking for parent devices")?;
-        crate::blockdev::init_parent_devices(devices);
+        let sysroot = prep_before_update()?;
         bootupd::client_run_update(&sysroot)
     }
 
     /// Runner for `update` verb.
     fn run_adopt_and_update() -> Result<()> {
         ensure_running_in_systemd()?;
-        let sysroot = openat::Dir::open("/").context("Opening root dir")?;
-        let dest_fd = format!("/proc/self/fd/{}", sysroot.as_raw_fd());
-        let dest_root = std::fs::read_link(dest_fd)?;
-
-        let devices = crate::blockdev::get_devices(&dest_root)
-            .with_context(|| "while looking for parent devices")?;
-        crate::blockdev::init_parent_devices(devices);
+        let sysroot = prep_before_update()?;
         bootupd::client_run_adopt_and_update(&sysroot)
     }
 
@@ -228,3 +216,15 @@ fn run_status_in_container(json_format: bool) -> Result<()> {
     }
     Ok(())
 }
+
+/// Initialize parent devices to prepare the update
+fn prep_before_update() -> Result<openat::Dir> {
+    let sysroot = openat::Dir::open("/").context("Opening root dir")?;
+    let dest_fd = format!("/proc/self/fd/{}", sysroot.as_raw_fd());
+    let dest_root = std::fs::read_link(dest_fd)?;
+
+    let devices = crate::blockdev::get_devices(&dest_root)
+        .with_context(|| "while looking for parent devices")?;
+    crate::blockdev::init_parent_devices(devices);
+    Ok(sysroot)
+}