KubeOS/0003-fix-os-agent-use-findmnt-to-find-out-which-device-mo.patch

From 59de6f644def5555c41e2ef14317e9178c40259f Mon Sep 17 00:00:00 2001
From: Yuhang Wei <weiyuhang3@huawei.com>
Date: Wed, 27 Nov 2024 18:34:14 +0000
Subject: [PATCH 03/11] fix(os-agent): use findmnt to find out which device
 mounted on /

use "findmnt -no SOURCE --mountpoint /" to get the device name mounted on /
use "lsblk -blno FSTYPE,SIZE" to get the fstype and partition size
This patch fixes the problem if there are multiple mountpoints on a device

Signed-off-by: Yuhang Wei <weiyuhang3@huawei.com>
---
 KubeOS-Rust/manager/src/sys_mgmt/config.rs | 21 ++----
 KubeOS-Rust/manager/src/utils/partition.rs | 86 +++++++++-------------
 2 files changed, 41 insertions(+), 66 deletions(-)

diff --git a/KubeOS-Rust/manager/src/sys_mgmt/config.rs b/KubeOS-Rust/manager/src/sys_mgmt/config.rs
index 8e42fa18..a491a429 100644
--- a/KubeOS-Rust/manager/src/sys_mgmt/config.rs
+++ b/KubeOS-Rust/manager/src/sys_mgmt/config.rs
@@ -826,13 +826,10 @@ mod tests {
         let mut executor = MockCommandExec::new();
 
         // the output shows that current root menuentry is A
-        let command_output1 = r#"vda                   23622320128
-vda1 /boot/efi vfat      61865984 BOOT
-vda2 /         ext4    3145728000 ROOT-A
-vda3           ext4    2621440000 ROOT-B
-vda4 /persist  ext4   17791188992 PERSIST
-"#;
-        executor.expect_run_command_with_output().times(1).returning(|_, _| Ok(command_output1.to_string()));
+        let findmnt_output1 = "/dev/vda2";
+        let lsblk_output1 = "ext4    3145728000\n";
+        executor.expect_run_command_with_output().times(1).returning(|_, _| Ok(findmnt_output1.to_string()));
+        executor.expect_run_command_with_output().times(1).returning(|_, _| Ok(lsblk_output1.to_string()));
 
         let result = grub_cmdline.get_config_partition(executor).unwrap();
         // it should return false because the current root menuentry is A and we want to configure current partition
@@ -840,14 +837,8 @@ vda4 /persist  ext4   17791188992 PERSIST
 
         let mut executor = MockCommandExec::new();
 
-        // the output shows that current root menuentry is A
-        let command_output1 = r#"vda                   23622320128
-vda1 /boot/efi vfat      61865984 BOOT
-vda2 /         ext4    3145728000 ROOT-A
-vda3           ext4    2621440000 ROOT-B
-vda4 /persist  ext4   17791188992 PERSIST
-"#;
-        executor.expect_run_command_with_output().times(1).returning(|_, _| Ok(command_output1.to_string()));
+        executor.expect_run_command_with_output().times(1).returning(|_, _| Ok(findmnt_output1.to_string()));
+        executor.expect_run_command_with_output().times(1).returning(|_, _| Ok(lsblk_output1.to_string()));
         grub_cmdline.is_cur_partition = false;
         let result = grub_cmdline.get_config_partition(executor).unwrap();
         // it should return true because the current root menuentry is A and we want to configure next partition
diff --git a/KubeOS-Rust/manager/src/utils/partition.rs b/KubeOS-Rust/manager/src/utils/partition.rs
index 4941ee9d..b2c095c6 100644
--- a/KubeOS-Rust/manager/src/utils/partition.rs
+++ b/KubeOS-Rust/manager/src/utils/partition.rs
@@ -25,43 +25,33 @@ pub struct PartitionInfo {
 
 /// get_partition_info returns the current partition info and the next partition info.
 pub fn get_partition_info<T: CommandExecutor>(executor: &T) -> Result<(PartitionInfo, PartitionInfo), anyhow::Error> {
-    let lsblk = executor.run_command_with_output("lsblk", &["-blno", "NAME,MOUNTPOINT,FSTYPE,SIZE,LABEL"])?;
     let mut cur_partition = PartitionInfo::default();
     let mut next_partition = PartitionInfo::default();
-    let mut found_boot = 0;
-    trace!("get_partition_info lsblk command output:\n{}", lsblk);
-    for line in lsblk.lines() {
-        let res: Vec<&str> = line.split_whitespace().collect();
-        if res.len() == 5 && res[4] == "BOOT" {
-            trace!("Found boot partition:\n{:?}", res);
-            found_boot = 2;
-            continue;
-        }
-        if found_boot > 0 {
-            trace!("Handling two root partitions:\n{:?}", res);
-            if res[1] == "/" {
-                // current partition
-                cur_partition.device = format!("/dev/{}", res[0]).to_string();
-                cur_partition.fs_type = res[2].to_string();
-                cur_partition.size = res[3]
-                    .parse()
-                    .with_context(|| format!("Failed to parse current partition size to i64: \"{}\"", res[3]))?;
-                cur_partition.menuentry = if res[0].contains("2") { String::from("A") } else { String::from("B") };
-            } else {
-                // next partition
-                next_partition.device = format!("/dev/{}", res[0]).to_string();
-                next_partition.fs_type = res[1].to_string();
-                next_partition.size = res[2]
-                    .parse()
-                    .with_context(|| format!("Failed to parse next partition size to i64: \"{}\"", res[2]))?;
-                next_partition.menuentry = if res[0].contains("2") { String::from("A") } else { String::from("B") };
-            }
-            found_boot -= 1;
-        }
+    cur_partition.device = executor.run_command_with_output("findmnt", &["-no", "SOURCE", "--mountpoint", "/"])?;
+    trace!("{} is mounted on /", cur_partition.device);
+    if cur_partition.device.contains('2') {
+        cur_partition.menuentry = String::from("A");
+        next_partition.menuentry = String::from("B");
+        next_partition.device = cur_partition.device.replace("2", "3");
+    } else if cur_partition.device.contains('3') {
+        cur_partition.menuentry = String::from("B");
+        next_partition.menuentry = String::from("A");
+        next_partition.device = cur_partition.device.replace("3", "2");
+    } else {
+        bail!("Failed to get partition info, / is not mounted on the second or the third partition");
     }
-    if cur_partition.menuentry.is_empty() || next_partition.menuentry.is_empty() {
-        bail!("Failed to get partition info, lsblk output: {}", lsblk);
+    let lsblk = executor.run_command_with_output("lsblk", &["-blno", "FSTYPE,SIZE", &cur_partition.device])?;
+    trace!("get_partition_info lsblk command output:\n{}", lsblk);
+    let elements: Vec<&str> = lsblk.split_whitespace().collect();
+    if elements.len() != 2 {
+        bail!("Failed to get partition info of FSTYPE and SIZE, lsblk output: {}", lsblk);
     }
+    cur_partition.fs_type = elements[0].to_string();
+    next_partition.fs_type = elements[0].to_string();
+    cur_partition.size = elements[1]
+        .parse()
+        .with_context(|| format!("Failed to parse current partition size to i64: \"{}\"", elements[1]))?;
+    next_partition.size = cur_partition.size;
     Ok((cur_partition, next_partition))
 }
 
@@ -94,14 +84,11 @@ mod tests {
     #[test]
     fn test_get_partition_info() {
         init();
-        let command_output1 = r#"vda                   23622320128
-vda1 /boot/efi vfat      61865984 BOOT
-vda2 /         ext4    3145728000 ROOT-A
-vda3           ext4    2621440000 ROOT-B
-vda4 /persist  ext4   17791188992 PERSIST
-"#;
+        let findmnt_output1 = "/dev/vda2";
+        let lsblk_output1 = "ext4    3145728000\n";
         let mut mock = MockCommandExec::new();
-        mock.expect_run_command_with_output().times(1).returning(|_, _| Ok(command_output1.to_string()));
+        mock.expect_run_command_with_output().times(1).returning(|_, _| Ok(findmnt_output1.to_string()));
+        mock.expect_run_command_with_output().times(1).returning(|_, _| Ok(lsblk_output1.to_string()));
         let res = get_partition_info(&mock).unwrap();
         let expect_res = (
             PartitionInfo {
@@ -114,25 +101,22 @@ vda4 /persist  ext4   17791188992 PERSIST
                 device: "/dev/vda3".to_string(),
                 menuentry: "B".to_string(),
                 fs_type: "ext4".to_string(),
-                size: 2621440000,
+                size: 3145728000,
             },
         );
         assert_eq!(res, expect_res);
 
-        let command_output2 = r#"vda                   23622320128
-vda1 /boot/efi vfat      61865984 BOOT
-vda2           ext4    3145728000 ROOT-A
-vda3 /         ext4    2621440000 ROOT-B
-vda4 /persist  ext4   17791188992 PERSIST
-"#;
-        mock.expect_run_command_with_output().times(1).returning(|_, _| Ok(command_output2.to_string()));
+        let findmnt_output2 = "/dev/vda3";
+        let lsblk_output2 = "ext4    3145728000\n";
+        mock.expect_run_command_with_output().times(1).returning(|_, _| Ok(findmnt_output2.to_string()));
+        mock.expect_run_command_with_output().times(1).returning(|_, _| Ok(lsblk_output2.to_string()));
         let res = get_partition_info(&mock).unwrap();
         let expect_res = (
             PartitionInfo {
                 device: "/dev/vda3".to_string(),
                 menuentry: "B".to_string(),
                 fs_type: "ext4".to_string(),
-                size: 2621440000,
+                size: 3145728000,
             },
             PartitionInfo {
                 device: "/dev/vda2".to_string(),
@@ -148,8 +132,8 @@ vda4 /persist  ext4   17791188992 PERSIST
         let res = get_partition_info(&mock);
         assert!(res.is_err());
 
-        let command_output4 = "sda4 / ext4 13000245248";
-        mock.expect_run_command_with_output().times(1).returning(|_, _| Ok(command_output4.to_string()));
+        let findmnt_output3 = "/dev/vda4";
+        mock.expect_run_command_with_output().times(1).returning(|_, _| Ok(findmnt_output3.to_string()));
         let res = get_partition_info(&mock);
         assert!(res.is_err());
     }
-- 
2.39.5 (Apple Git-154)