From 7112182dbcbd55925df7d33d11d8090cd043d16f Mon Sep 17 00:00:00 2001
From: Paul Otten <potten@my.bcit.ca>
Date: Thu, 1 Apr 2021 18:37:20 -0400
Subject: [PATCH] Consider device id when comparing files

---
 src/uu/du/src/du.rs | 38 ++++++++++++++++++++++++++------------
 1 file changed, 26 insertions(+), 12 deletions(-)

diff --git a/src/uu/du/src/du.rs b/src/uu/du/src/du.rs
index 2eb7bd658..c311f982e 100644
--- a/src/uu/du/src/du.rs
+++ b/src/uu/du/src/du.rs
@@ -32,7 +32,7 @@ use winapi::um::minwinbase::{FileStandardInfo, FileIdInfo};
 #[cfg(windows)]
 use winapi::um::winbase::GetFileInformationByHandleEx;
 #[cfg(windows)]
-use winapi::um::winnt::FILE_ID_128;
+use winapi::um::winnt::{FILE_ID_128, ULONGLONG};
 
 const NAME: &str = "du";
 const SUMMARY: &str = "estimate file space usage";
@@ -58,12 +58,18 @@ struct Options {
     separate_dirs: bool,
 }
 
+#[derive(PartialEq, Eq, Hash, Clone, Copy)]
+struct FileInfo {
+    file_id: u128,
+    dev_id: u64,
+}
+
 struct Stat {
     path: PathBuf,
     is_dir: bool,
     size: u64,
     blocks: u64,
-    inode: Option<u128>,
+    inode: Option<FileInfo>,
     created: u64,
     accessed: u64,
     modified: u64,
@@ -73,13 +79,18 @@ impl Stat {
     fn new(path: PathBuf) -> Result<Stat> {
         let metadata = fs::symlink_metadata(&path)?;
 
+        #[cfg(not(windows))]
+        let file_info = FileInfo {
+            file_id: metadata.ino() as u128,
+            dev_id: metadata.dev(),
+        };
         #[cfg(not(windows))]
         return Ok(Stat {
             path,
             is_dir: metadata.is_dir(),
             size: metadata.len(),
             blocks: metadata.blocks() as u64,
-            inode: Some(metadata.ino() as u128),
+            inode: Some(file_info),
             created: metadata.mtime() as u64,
             accessed: metadata.atime() as u64,
             modified: metadata.mtime() as u64,
@@ -88,14 +99,14 @@ impl Stat {
         #[cfg(windows)]
         let size_on_disk = get_size_on_disk(&path);
         #[cfg(windows)]
-        let inode = get_inode(&path);
+        let file_info = get_file_info(&path);
         #[cfg(windows)]
         Ok(Stat {
             path,
             is_dir: metadata.is_dir(),
             size: metadata.len(),
             blocks: size_on_disk / 1024 * 2,
-            inode: inode,
+            inode: file_info,
             created: windows_time_to_unix_time(metadata.creation_time()),
             accessed: windows_time_to_unix_time(metadata.last_access_time()),
             modified: windows_time_to_unix_time(metadata.last_write_time()),
@@ -143,12 +154,12 @@ fn get_size_on_disk(path: &PathBuf) -> u64 {
 }
 
 #[cfg(windows)]
-fn get_inode(path: &PathBuf) -> Option<u128> {
-    let mut inode = None;
+fn get_file_info(path: &PathBuf) -> Option<FileInfo> {
+    let mut result = None;
 
     let file = match fs::File::open(path) {
         Ok(file) => file,
-        Err(_) => return inode,
+        Err(_) => return result,
     };
 
     let handle = file.as_raw_handle();
@@ -165,11 +176,14 @@ fn get_inode(path: &PathBuf) -> Option<u128> {
         );
 
         if success != 0 {
-            inode = Some(std::mem::transmute::<FILE_ID_128, u128>(file_info.FileId));
+            result = Some(FileInfo {
+                file_id: std::mem::transmute::<FILE_ID_128, u128>(file_info.FileId),
+                dev_id: std::mem::transmute::<ULONGLONG, u64>(file_info.VolumeSerialNumber),
+            });
         }
     }
 
-    inode
+    result
 }
 
 fn unit_string_to_number(s: &str) -> Option<u64> {
@@ -239,7 +253,7 @@ fn du(
     mut my_stat: Stat,
     options: &Options,
     depth: usize,
-    inodes: &mut HashSet<u128>,
+    inodes: &mut HashSet<FileInfo>,
 ) -> Box<dyn DoubleEndedIterator<Item = Stat>> {
     let mut stats = vec![];
     let mut futures = vec![];
@@ -523,7 +537,7 @@ Try '{} --help' for more information.",
         let path = PathBuf::from(&path_str);
         match Stat::new(path) {
             Ok(stat) => {
-                let mut inodes: HashSet<u128> = HashSet::new();
+                let mut inodes: HashSet<FileInfo> = HashSet::new();
 
                 let iter = du(stat, &options, 0, &mut inodes);
                 let (_, len) = iter.size_hint();