mount: fix iPod automount (lsblk flags + udisks suffixed paths)

Two bugs kept the connected iPod from being auto-mounted:

- `lsblk -o PATH,LABEL -n -l -P` is invalid (--pairs and --list are
  mutually exclusive), so device lookup by label always failed with
  "no block device found" — a regression from the earlier parse fix.
  Drop -l.
- udisks mounted the iPod volume at /media/sebastian/IPOD1 because the
  configured directory /media/sebastian/IPOD already exists, so even a
  resolved device failed with AlreadyMounted. The configured mount point
  is now treated as a hint: mounted_path_for() resolves an exact mount or
  the lowest-numbered udisks-suffixed sibling (IPOD → IPOD1) from
  /proc/self/mountinfo, and the sync destination, storage stats, settings
  display and fatsort resolution all use the real mount.

Also harden fatsort: resolve_fatsort_target now refuses to run when the
path is not a mount point, so findmnt can never fall back to the root
filesystem's block device.

Verified on the connected iPod: mounted_path_for → IPOD1,
resolve_block_device → /dev/sdb2, mount_device → "already mounted at
/media/sebastian/IPOD1", UI shows ● mounted with 9.7 GiB free · 92% and
mount point ✓ /media/sebastian/IPOD1.

Bump to 0.3.3.

Cargo.lock

@@ -253,7 +253,7 @@ dependencies = [
 
 [[package]]
 name = "dap-tui"
-version = "0.3.2"
+version = "0.3.3"
 dependencies = [
  "anyhow",
  "chrono",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "dap-tui"
-version = "0.3.2"
+version = "0.3.3"
 edition = "2021"
 description = "Device sync for portable players — TUI edition (ratatui)"
 license = "MIT"

README.md

@@ -107,9 +107,12 @@ mounts the target first (resolved by mount-point label via `lsblk`). Only the
 mlove `fatsort` step needs root (raw block device).
 
 Mount status and sync targets are validated against the kernel mount table
-(`/proc/self/mountinfo`), not just directory existence: if the configured
-`mount_point` exists but is not actually mounted, `dap-tui` refuses to sync to
-it rather than writing the library onto the root filesystem.
+(`/proc/self/mountinfo`), not just directory existence. The configured
+`mount_point` is a hint: if udisks mounted the volume at a suffixed sibling
+because the configured directory already existed (e.g. `IPOD` → `IPOD1`),
+dap-tui follows the actual mount and uses it as the sync destination. If the
+path exists but is not a mount at all, syncing into it is refused rather than
+writing the library onto the root filesystem.
 
 ## Development
 

src/config.rs

@@ -122,12 +122,14 @@ pub struct Config {
 
 impl Config {
     /// Refresh `Device::mounted` from the kernel mount table (no subprocess).
+    /// A device counts as mounted when its volume is mounted at the configured
+    /// path or at a udisks-suffixed sibling (e.g. `IPOD` → `IPOD1`).
     pub fn refresh_mounts(&mut self) {
         for d in self.devices.iter_mut() {
             d.mounted = d
                 .mount_point
                 .as_deref()
-                .map(crate::disk::is_mounted)
+                .map(|p| crate::disk::mounted_path_for(p).is_some())
                 .unwrap_or(false);
         }
     }

src/disk.rs

@@ -1,4 +1,4 @@
-use std::path::Path;
+use std::path::{Path, PathBuf};
 
 /// Whether `path` is currently a mount point.
 ///
@@ -26,6 +26,56 @@ pub fn is_mounted(path: &Path) -> bool {
     path.exists()
 }
 
+/// Mount points currently listed in the kernel mount table.
+fn mount_points() -> Vec<PathBuf> {
+    #[cfg(target_os = "linux")]
+    if let Ok(text) = std::fs::read_to_string("/proc/self/mountinfo") {
+        return text
+            .lines()
+            .filter_map(|line| line.split(' ').nth(4))
+            .map(|field| PathBuf::from(unescape_octal(field)))
+            .collect();
+    }
+    Vec::new()
+}
+
+/// Where the volume configured at `path` is actually mounted.
+///
+/// udisks mounts a volume at `/media/$USER/$LABEL`; if that directory already
+/// exists (e.g. a leftover mount dir after an unclean eject) it appends a
+/// number, so `/media/sebastian/IPOD` becomes `/media/sebastian/IPOD1`. This
+/// resolves the exact path or the lowest-numbered suffixed sibling, so the
+/// configured path is treated as a hint rather than a hard requirement.
+pub fn mounted_path_for(path: &Path) -> Option<PathBuf> {
+    if is_mounted(path) {
+        return Some(path.to_path_buf());
+    }
+    let parent = path.parent()?;
+    let base = path.file_name()?.to_string_lossy().to_string();
+    mount_points()
+        .into_iter()
+        .filter_map(|mp| mount_suffix_rank(parent, &base, &mp).map(|rank| (rank, mp)))
+        .min_by_key(|(rank, _)| *rank)
+        .map(|(_, mp)| mp)
+}
+
+/// Rank of a mount point relative to a configured path: 0 for an exact match,
+/// `n` for `name{n}` (udisks' uniquifying suffix), `None` otherwise.
+fn mount_suffix_rank(parent: &Path, base: &str, candidate: &Path) -> Option<u32> {
+    if candidate.parent() != Some(parent) {
+        return None;
+    }
+    let name = candidate.file_name()?.to_string_lossy();
+    let rest = name.strip_prefix(base)?;
+    if rest.is_empty() {
+        return Some(0);
+    }
+    if rest.chars().all(|c| c.is_ascii_digit()) {
+        return rest.parse().ok();
+    }
+    None
+}
+
 /// Undo the octal escaping (`\040` etc.) used by /proc mount tables.
 fn unescape_octal(s: &str) -> String {
     let bytes = s.as_bytes();
@@ -84,7 +134,31 @@ pub fn fmt_bytes(n: u64) -> String {
 
 #[cfg(test)]
 mod tests {
-    use super::{fmt_bytes, unescape_octal};
+    use super::{fmt_bytes, mounted_path_for, mount_suffix_rank, unescape_octal};
+
+    #[test]
+    fn ranks_udisks_suffixed_mounts() {
+        let parent = std::path::Path::new("/media/sebastian");
+        let rank = |c: &str| mount_suffix_rank(parent, "IPOD", std::path::Path::new(c));
+        assert_eq!(rank("/media/sebastian/IPOD"), Some(0));
+        assert_eq!(rank("/media/sebastian/IPOD1"), Some(1));
+        assert_eq!(rank("/media/sebastian/IPOD12"), Some(12));
+        // non-numeric suffixes and other directories must not match
+        assert_eq!(rank("/media/sebastian/IPODX"), None);
+        assert_eq!(rank("/media/sebastian/IPOD-2"), None);
+        assert_eq!(rank("/media/other/IPOD1"), None);
+        assert_eq!(rank("/media/sebastian/IPOD1/extra"), None);
+    }
+
+    #[test]
+    #[cfg(target_os = "linux")]
+    fn resolves_exact_mounts() {
+        // `/` is always mounted; mounted_path_for must return it unchanged.
+        assert_eq!(
+            mounted_path_for(std::path::Path::new("/")),
+            Some(std::path::PathBuf::from("/"))
+        );
+    }
 
     #[test]
     fn unescapes_mountinfo_paths() {

src/engine.rs

@@ -542,29 +542,43 @@ fn scan_music_dir(base: &Path) -> HashMap<String, (u64, i64)> {
 }
 
 fn run_rsync_device(config: &Config, device: &Device, ctx: &WorkerCtx) -> Result<(), String> {
-    let mount = device
+    let configured = device
         .mount_point
         .as_ref()
         .ok_or_else(|| "mount_point is not set for this device".to_string())?;
 
-    if !crate::disk::is_mounted(mount) {
-        ctx.log(
-            LogLevel::Info,
-            format!("device not mounted at {} — trying udisksctl…", mount.display()),
-        );
-        match crate::udisks::mount_device(mount) {
-            Ok(msg) => ctx.log(LogLevel::Info, format!("auto-mounted: {msg}")),
-            Err(e) => {
-                return Err(format!(
-                    "device not mounted at {} — connect & mount it (m) and retry. {e}",
-                    mount.display()
-                ));
+    // Trust the kernel mount table over the configured path: udisks may have
+    // mounted the volume at a suffixed path (e.g. /media/.../IPOD1) because the
+    // configured directory already existed.
+    let mount = match crate::disk::mounted_path_for(configured) {
+        Some(p) => p,
+        None => {
+            ctx.log(
+                LogLevel::Info,
+                format!(
+                    "device not mounted at {} — trying udisksctl…",
+                    configured.display()
+                ),
+            );
+            match crate::udisks::mount_device(configured) {
+                Ok(msg) => ctx.log(LogLevel::Info, format!("auto-mounted: {msg}")),
+                Err(e) => {
+                    return Err(format!(
+                        "device not mounted at {} — connect & mount it (m) and retry. {e}",
+                        configured.display()
+                    ));
+                }
             }
+            crate::disk::mounted_path_for(configured).ok_or_else(|| {
+                format!(
+                    "auto-mount of {} did not yield a mount point",
+                    configured.display()
+                )
+            })?
         }
-    }
-    // A leftover (empty) mount-point directory must not be mistaken for a
-    // mounted device — rsync would otherwise happily fill the root filesystem.
-    if !crate::disk::is_mounted(mount) {
+    };
+    // Paranoia: never write into a directory that is not actually a mount.
+    if !crate::disk::is_mounted(&mount) {
         return Err(format!(
             "{} exists but is not a mount point — refusing to sync. Connect the device and press 'm'.",
             mount.display()
@@ -732,15 +746,17 @@ fn capture(cmd: &str, args: &[&str]) -> Result<(i32, String), String> {
 }
 
 fn finalize_fat(device: &Device, ctx: &WorkerCtx) -> Result<(), String> {
-    let mount = device
+    let configured = device
         .mount_point
         .as_ref()
         .ok_or_else(|| "mount_point is required to run fatsort".to_string())?;
+    // Use the actual mount point in case udisks moved it to a suffixed path.
+    let mount = crate::disk::mounted_path_for(configured).unwrap_or_else(|| configured.clone());
 
-    let target = resolve_fatsort_target(mount)?;
+    let target = resolve_fatsort_target(&mount)?;
 
     ctx.log(LogLevel::Info, format!("Unmounting {mount_display}", mount_display = mount.display()));
-    match crate::udisks::unmount_device(mount) {
+    match crate::udisks::unmount_device(&mount) {
         Ok(msg) => ctx.log(LogLevel::Info, format!("unmounted: {msg}")),
         Err(e) => {
             // fall back to sudo for setups without udisks
@@ -771,6 +787,12 @@ fn resolve_fatsort_target(mount: &Path) -> Result<String, String> {
     if !mount.is_dir() {
         return Ok(mount.display().to_string());
     }
+    // Never let findmnt fall back to the parent filesystem (e.g. the root
+    // disk) when the directory is not actually a mount point — fatsort on the
+    // wrong block device would corrupt it.
+    if !crate::disk::is_mounted(mount) {
+        return Err(format!("{} is not a mount point", mount.display()));
+    }
     let (code, out) = capture(
         "findmnt",
         &["-n", "-o", "SOURCE", "-T", mount.to_str().unwrap_or("")],

src/udisks.rs

@@ -19,11 +19,10 @@ fn run(cmd: &str, args: &[&str]) -> (bool, String) {
 }
 
 fn resolve_block_device(path: &Path) -> Option<String> {
-    // Only trust findmnt when the path really is a mount point; otherwise
-    // findmnt happily reports the containing filesystem (e.g. /), which would
-    // make us "mount" the root device.
-    if crate::disk::is_mounted(path) {
-        let (ok, out) = run("findmnt", &["-n", "-o", "SOURCE", "-T", path.to_str()?]);
+    // If the volume is already mounted (possibly at a udisks-suffixed path
+    // like IPOD1), ask findmnt for its source device.
+    if let Some(mp) = crate::disk::mounted_path_for(path) {
+        let (ok, out) = run("findmnt", &["-n", "-o", "SOURCE", "-T", mp.to_str()?]);
         if ok {
             let src = out.trim();
             if src.starts_with("/dev/") {
@@ -31,8 +30,10 @@ fn resolve_block_device(path: &Path) -> Option<String> {
             }
         }
     }
+    // Not mounted: match a partition label to the configured mount point's
+    // basename (e.g. `/media/sebastian/IPOD` → label `IPOD`).
     let wanted = path.file_name()?.to_string_lossy().to_lowercase();
-    let (ok, out) = run("lsblk", &["-o", "PATH,LABEL", "-n", "-l", "-P"]);
+    let (ok, out) = run("lsblk", &["-o", "PATH,LABEL", "-n", "-P"]);
     if !ok {
         return None;
     }
@@ -50,6 +51,16 @@ fn resolve_block_device(path: &Path) -> Option<String> {
     None
 }
 
+/// Current mount target of a block device, if any.
+fn mounted_target(dev: &str) -> Option<std::path::PathBuf> {
+    let (ok, out) = run("findmnt", &["-n", "-o", "TARGET", "-S", dev]);
+    if ok && !out.trim().is_empty() {
+        Some(std::path::PathBuf::from(out.trim()))
+    } else {
+        None
+    }
+}
+
 /// Extract a `KEY="value"` field from `lsblk -P` output.
 fn field(line: &str, key: &str) -> Option<String> {
     let needle = format!("{key}=\"");
@@ -60,13 +71,25 @@ fn field(line: &str, key: &str) -> Option<String> {
 }
 
 pub fn mount_device(path: &Path) -> Result<String, String> {
+    // Already mounted, possibly at a udisks-suffixed path.
+    if let Some(mp) = crate::disk::mounted_path_for(path) {
+        return Ok(format!("already mounted at {}", mp.display()));
+    }
     let Some(dev) = resolve_block_device(path) else {
         return Err(format!("no block device found for {}", path.display()));
     };
+    if let Some(mp) = mounted_target(&dev) {
+        return Ok(format!("already mounted at {}", mp.display()));
+    }
     let (ok, detail) = run("udisksctl", &["mount", "-b", dev.as_str()]);
     if ok {
         Ok(detail)
     } else {
+        // A concurrent/late mount makes AlreadyMounted spurious: report
+        // success when the kernel now has the device mounted.
+        if let Some(mp) = mounted_target(&dev) {
+            return Ok(format!("mounted at {}", mp.display()));
+        }
         Err(format!("udisksctl mount {dev} failed: {detail}"))
     }
 }
@@ -82,3 +105,30 @@ pub fn unmount_device(path: &Path) -> Result<String, String> {
         Err(format!("udisksctl unmount {dev} failed: {detail}"))
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::field;
+
+    #[test]
+    fn parses_lsblk_pairs() {
+        assert_eq!(
+            field(r#"PATH="/dev/sdb2" LABEL="IPOD""#, "PATH").as_deref(),
+            Some("/dev/sdb2")
+        );
+        assert_eq!(
+            field(r#"PATH="/dev/sdb2" LABEL="IPOD""#, "LABEL").as_deref(),
+            Some("IPOD")
+        );
+        assert_eq!(
+            field(r#"PATH="/dev/sdb1" LABEL="""#, "LABEL").as_deref(),
+            Some("")
+        );
+        assert_eq!(
+            field(r#"LABEL="My Disk" PATH="/dev/sdc1""#, "LABEL").as_deref(),
+            Some("My Disk")
+        );
+        assert_eq!(field(r#"PATH="/dev/sdc1""#, "LABEL"), None);
+    }
+
+}

src/ui/tabs/dashboard.rs

@@ -147,11 +147,14 @@ fn draw_device_card(f: &mut Frame, area: Rect, app: &App, device: &crate::config
         line("last sync", last, last_style),
     ];
 
-    // Mounted storage usage. The compact value ("276.8 GiB free · 39%") fits
-    // the card width, unlike the old "459.5 GiB total · 276.8 GiB free" which
-    // was truncated mid-number.
+    // Mounted storage usage. udisks may mount the volume at a suffixed path
+    // (IPOD → IPOD1), so report stats for wherever it actually is mounted.
+    let actual_mount = device
+        .mount_point
+        .as_deref()
+        .and_then(crate::disk::mounted_path_for);
     let storage = if device.mounted {
-        device.mount_point.as_ref().and_then(|p| disk_stats(p))
+        actual_mount.as_deref().and_then(disk_stats)
     } else {
         None
     };
@@ -232,7 +235,12 @@ fn draw_settings_card(f: &mut Frame, area: Rect, device: &crate::config::Device)
         Style::default().fg(theme::FG),
     ));
     match device.mount_point.as_deref() {
-        Some(p) => lines.push(path_kv(l_mount, p, value_w, lw)),
+        Some(p) => {
+            // Show where it is actually mounted when udisks used a suffixed
+            // path (e.g. the configured IPOD dir existed, so it chose IPOD1).
+            let shown = crate::disk::mounted_path_for(p).unwrap_or_else(|| p.to_path_buf());
+            lines.push(path_kv(l_mount, &shown, value_w, lw));
+        }
         None => lines.push(line(l_mount, "—".to_string(), Style::default().fg(theme::DIM))),
     }
     lines.push(line(