Clean up windows performance

Instead of generating random values for the drive and inode counter on
windows we return None instead

src/utils/mod.rs

@@ -85,10 +85,8 @@ pub fn get_dir_tree<P: AsRef<Path>>(
         None
     };
 
-    let mut fake_inode_counter = u64::max_value();
     let mut examine_dir_args = ExamineDirMutArsg {
         data: &mut data,
-        fake_inode_counter: &mut fake_inode_counter,
         file_count_no_permission: &mut permissions,
     };
     for b in top_level_names.iter() {
@@ -127,7 +125,6 @@ pub fn normalize_path<P: AsRef<Path>>(path: P) -> PathBuf {
 struct ExamineDirMutArsg<'a> {
     data: &'a mut HashMap<PathBuf, u64>,
     file_count_no_permission: &'a mut u64,
-    fake_inode_counter: &'a mut u64,
 }
 
 fn examine_dir<P: AsRef<Path>>(
@@ -149,8 +146,7 @@ fn examine_dir<P: AsRef<Path>>(
 
     'entry: for entry in iter {
         if let Ok(e) = entry {
-            let maybe_size_and_inode =
+            let maybe_size_and_inode = get_metadata(&e, apparent_size);
-                get_metadata(&e, apparent_size, &mut mut_args.fake_inode_counter);
 
             if let Some(dirs) = ignore_directories {
                 let path = e.path();
@@ -167,8 +163,9 @@ fn examine_dir<P: AsRef<Path>>(
             }
 
             match maybe_size_and_inode {
-                Some((size, inode, device)) => {
+                Some(data) => {
-                    if !should_ignore_file(apparent_size, filesystems, &mut inodes, inode, device) {
+                    let (size, inode_device) = data;
+                    if !should_ignore_file(apparent_size, filesystems, &mut inodes, inode_device) {
                         process_file_with_size_and_inode(top_dir, mut_args.data, e, size)
                     }
                 }
@@ -184,9 +181,12 @@ fn should_ignore_file(
     apparent_size: bool,
     restricted_filesystems: &Option<HashSet<u64>>,
     inodes: &mut HashSet<(u64, u64)>,
-    inode: u64,
+    maybe_inode_device: Option<(u64, u64)>,
-    device: u64,
 ) -> bool {
+    match maybe_inode_device {
+        None => false,
+        Some(data) => {
+            let (inode, device) = data;
             // Ignore files on different devices (if flag applied)
             if let Some(rs) = restricted_filesystems {
                 if !rs.contains(&device) {
@@ -202,6 +202,8 @@ fn should_ignore_file(
                 inodes.insert((inode, device));
             }
             false
+        }
+    }
 }
 
 fn process_file_with_size_and_inode<P: AsRef<Path>>(
@@ -365,14 +367,19 @@ mod tests {
         let mut files = HashSet::new();
         files.insert((10, 20));
 
-        assert!(!should_ignore_file(true, &None, &mut files, 0, 0));
+        assert!(!should_ignore_file(true, &None, &mut files, Some((0, 0))));
 
         // New file is not known it will be inserted to the hashmp and should not be ignored
-        assert!(!should_ignore_file(false, &None, &mut files, 11, 12));
+        assert!(!should_ignore_file(
+            false,
+            &None,
+            &mut files,
+            Some((11, 12))
+        ));
         assert!(files.contains(&(11, 12)));
 
         // The same file will be ignored the second time
-        assert!(should_ignore_file(false, &None, &mut files, 11, 12));
+        assert!(should_ignore_file(false, &None, &mut files, Some((11, 12))));
     }
 
     #[test]
@@ -386,11 +393,11 @@ mod tests {
 
         // If we are looking at a different device (disk) and the device flag is set
         // then apparent_size is irrelevant - we ignore files on other devices
-        assert!(should_ignore_file(false, &od, &mut files, 11, 12));
+        assert!(should_ignore_file(false, &od, &mut files, Some((11, 12))));
-        assert!(should_ignore_file(true, &od, &mut files, 11, 12));
+        assert!(should_ignore_file(true, &od, &mut files, Some((11, 12))));
 
         // We do not ignore files on the same device
-        assert!(!should_ignore_file(false, &od, &mut files, 2, 99));
+        assert!(!should_ignore_file(false, &od, &mut files, Some((2, 99))));
-        assert!(!should_ignore_file(true, &od, &mut files, 2, 99));
+        assert!(!should_ignore_file(true, &od, &mut files, Some((2, 99))));
     }
 }

src/utils/platform.rs

@@ -12,27 +12,19 @@ fn get_block_size() -> u64 {
 }
 
 #[cfg(target_family = "unix")]
-pub fn get_metadata(
+pub fn get_metadata(d: &DirEntry, use_apparent_size: bool) -> Option<(u64, Option<(u64, u64)>)> {
-    d: &DirEntry,
-    use_apparent_size: bool,
-    _fake_inode_counter: &mut u64,
-) -> Option<(u64, u64, u64)> {
     use std::os::unix::fs::MetadataExt;
     d.metadata.as_ref().unwrap().as_ref().ok().map(|md| {
         if use_apparent_size {
-            (md.len(), md.ino(), md.dev())
+            (md.len(), Some((md.ino(), md.dev())))
         } else {
-            (md.blocks() * get_block_size(), md.ino(), md.dev())
+            (md.blocks() * get_block_size(), Some((md.ino(), md.dev())))
         }
     })
 }
 
 #[cfg(target_family = "windows")]
-pub fn get_metadata(
+pub fn get_metadata(d: &DirEntry, _use_apparent_size: bool) -> Option<(u64, Option<(u64, u64)>)> {
-    d: &DirEntry,
-    _use_apparent_size: bool,
-    fake_inode_counter: &mut u64,
-) -> Option<(u64, u64, u64)> {
     // On windows opening the file to get size, file ID and volume can be very
     // expensive because 1) it causes a few system calls, and more importantly 2) it can cause
     // windows defender to scan the file.
@@ -69,7 +61,7 @@ pub fn get_metadata(
     // Consistently opening the file: 30 minutes.
     // With this optimization:         8 sec.
 
-    fn get_metadata_expensive(d: &DirEntry) -> Option<(u64, u64, u64)> {
+    fn get_metadata_expensive(d: &DirEntry) -> Option<(u64, Option<(u64, u64)>)> {
         use winapi_util::file::information;
         use winapi_util::Handle;
 
@@ -78,8 +70,7 @@ pub fn get_metadata(
 
         Some((
             info.file_size(),
-            info.file_index(),
+            Some((info.file_index(), info.volume_serial_number())),
-            info.volume_serial_number(),
         ))
     }
 
@@ -99,8 +90,7 @@ pub fn get_metadata(
                 || attr_filtered == FILE_ATTRIBUTE_DIRECTORY
                 || md.file_attributes() == FILE_ATTRIBUTE_NORMAL
             {
-                *fake_inode_counter -= 1;
+                Some((md.len(), None))
-                Some((md.len(), *fake_inode_counter, 0xcafe_cafe_u64))
             } else {
                 get_metadata_expensive(&d)
             }