From 87c5823c4bbc2848cbfaf614c88027f5d7368d56 Mon Sep 17 00:00:00 2001
From: David Gibson <david@gibson.dropbear.id.au>
Date: Tue, 9 Feb 2021 12:05:48 +1100
Subject: [PATCH] agent/device: Add unit test for pcipath_to_sysfs()

Port this test from the Kata 1 Go agent to the Kata 2 Rust agent.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 src/agent/src/device.rs | 65 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)

diff --git a/src/agent/src/device.rs b/src/agent/src/device.rs
index b4d10a36d7..f69fa5c98f 100644
--- a/src/agent/src/device.rs
+++ b/src/agent/src/device.rs
@@ -435,6 +435,7 @@ pub fn update_device_cgroup(spec: &mut Spec) -> Result<()> {
 mod tests {
     use super::*;
     use oci::Linux;
+    use tempfile::tempdir;
 
     #[test]
     fn test_update_device_cgroup() {
@@ -714,4 +715,68 @@ mod tests {
         assert_eq!(Some(host_major), specresources.devices[1].major);
         assert_eq!(Some(host_minor), specresources.devices[1].minor);
     }
+
+    #[test]
+    fn test_pcipath_to_sysfs() {
+        let testdir = tempdir().expect("failed to create tmpdir");
+        let rootbuspath = testdir.path().to_str().unwrap();
+
+        let path2 = pci::Path::from_str("02").unwrap();
+        let path23 = pci::Path::from_str("02/03").unwrap();
+        let path234 = pci::Path::from_str("02/03/04").unwrap();
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path2);
+        assert_eq!(relpath.unwrap(), "/0000:00:02.0");
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path23);
+        assert!(relpath.is_err());
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path234);
+        assert!(relpath.is_err());
+
+        // Create mock sysfs files for the device at 0000:00:02.0
+        let bridge2path = format!("{}{}", rootbuspath, "/0000:00:02.0");
+
+        fs::create_dir_all(&bridge2path).unwrap();
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path2);
+        assert_eq!(relpath.unwrap(), "/0000:00:02.0");
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path23);
+        assert!(relpath.is_err());
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path234);
+        assert!(relpath.is_err());
+
+        // Create mock sysfs files to indicate that 0000:00:02.0 is a bridge to bus 01
+        let bridge2bus = "0000:01";
+        let bus2path = format!("{}/pci_bus/{}", bridge2path, bridge2bus);
+
+        fs::create_dir_all(bus2path).unwrap();
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path2);
+        assert_eq!(relpath.unwrap(), "/0000:00:02.0");
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path23);
+        assert_eq!(relpath.unwrap(), "/0000:00:02.0/0000:01:03.0");
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path234);
+        assert!(relpath.is_err());
+
+        // Create mock sysfs files for a bridge at 0000:01:03.0 to bus 02
+        let bridge3path = format!("{}/0000:01:03.0", bridge2path);
+        let bridge3bus = "0000:02";
+        let bus3path = format!("{}/pci_bus/{}", bridge3path, bridge3bus);
+
+        fs::create_dir_all(bus3path).unwrap();
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path2);
+        assert_eq!(relpath.unwrap(), "/0000:00:02.0");
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path23);
+        assert_eq!(relpath.unwrap(), "/0000:00:02.0/0000:01:03.0");
+
+        let relpath = pcipath_to_sysfs(rootbuspath, &path234);
+        assert_eq!(relpath.unwrap(), "/0000:00:02.0/0000:01:03.0/0000:02:04.0");
+    }
 }