ksud: make it compilable for non-android

userspace/ksud/src/mount.rs

@@ -0,0 +1,58 @@
+use anyhow::Result;
+
+#[cfg(target_os = "android")]
+use anyhow::{ensure, Context, Ok};
+#[cfg(target_os = "android")]
+use retry::delay::NoDelay;
+#[cfg(target_os = "android")]
+use sys_mount::{unmount, FilesystemType, Mount, MountFlags, UnmountFlags};
+
+#[cfg(target_os = "android")]
+fn do_mount_image(src: &str, target: &str) -> Result<()> {
+    Mount::builder()
+        .fstype(FilesystemType::from("ext4"))
+        .mount(src, target)
+        .with_context(|| format!("Failed to do mount: {src} -> {target}"))?;
+    Ok(())
+}
+
+#[cfg(target_os = "android")]
+pub fn mount_ext4(src: &str, target: &str) -> Result<()> {
+    // umount target first.
+    let _ = umount_dir(target);
+    let result = retry::retry(NoDelay.take(3), || do_mount_image(src, target));
+    ensure!(result.is_ok(), "Failed to mount {} -> {}", src, target);
+    Ok(())
+}
+
+#[cfg(target_os = "android")]
+pub fn umount_dir(src: &str) -> Result<()> {
+    unmount(src, UnmountFlags::empty()).with_context(|| format!("Failed to umount {src}"))?;
+    Ok(())
+}
+
+#[cfg(target_os = "android")]
+pub fn mount_overlay(lowerdir: &str, mnt: &str) -> Result<()> {
+    Mount::builder()
+        .fstype(FilesystemType::from("overlay"))
+        .flags(MountFlags::RDONLY)
+        .data(&format!("lowerdir={lowerdir}"))
+        .mount("overlay", mnt)
+        .map(|_| ())
+        .map_err(|e| anyhow::anyhow!("mount partition: {mnt} overlay failed: {e}"))
+}
+
+#[cfg(not(target_os = "android"))]
+pub fn mount_ext4(src: &str, target: &str) -> Result<()> {
+    unimplemented!()
+}
+
+#[cfg(not(target_os = "android"))]
+pub fn umount_dir(src: &str) -> Result<()> {
+    unimplemented!()
+}
+
+#[cfg(not(target_os = "android"))]
+pub fn mount_overlay(lowerdir: &str, mnt: &str) -> Result<()> {
+    unimplemented!()
+}