Support excluding filesystems with -x

https://github.com/bootandy/dust/issues/50

Add optional -x flag to limit search to the current filesystem.

Add (untested) support for windows for the equivalent of inode and
device.

src/main.rs

@@ -54,6 +54,12 @@ fn main() {
                 .long("full-paths")
                 .help("If set sub directories will not have their path shortened"),
         )
+        .arg(
+            Arg::with_name("limit_filesystem")
+                .short("x")
+                .long("limit-filesystem")
+                .help("Only count the files and directories in the same filesystem as the supplied directory"),
+        )
         .arg(
             Arg::with_name("display_apparent_size")
                 .short("s")
@@ -110,9 +116,15 @@ fn main() {
     }
 
     let use_apparent_size = options.is_present("display_apparent_size");
+    let limit_filesystem = options.is_present("limit_filesystem");
 
     let simplified_dirs = simplify_dir_names(target_dirs);
-    let (permissions, nodes) = get_dir_tree(&simplified_dirs, use_apparent_size, threads);
+    let (permissions, nodes) = get_dir_tree(
+        &simplified_dirs,
+        use_apparent_size,
+        limit_filesystem,
+        threads,
+    );
     let sorted_data = sort(nodes);
     let biggest_ones = {
         match depth {

src/utils/mod.rs

@@ -37,7 +37,8 @@ impl PartialEq for Node {
 }
 
 pub fn is_a_parent_of(parent: &str, child: &str) -> bool {
-    (child.starts_with(parent) && child.chars().nth(parent.chars().count()) == Some('/')) || parent == "/"
+    (child.starts_with(parent) && child.chars().nth(parent.chars().count()) == Some('/'))
+        || parent == "/"
 }
 
 pub fn simplify_dir_names(filenames: Vec<&str>) -> HashSet<String> {
@@ -69,16 +70,23 @@ pub fn simplify_dir_names(filenames: Vec<&str>) -> HashSet<String> {
 pub fn get_dir_tree(
     top_level_names: &HashSet<String>,
     apparent_size: bool,
+    limit_filesystem: bool,
     threads: Option<usize>,
 ) -> (bool, HashMap<String, u64>) {
     let mut permissions = 0;
     let mut inodes: HashSet<(u64, u64)> = HashSet::new();
     let mut data: HashMap<String, u64> = HashMap::new();
+    let restricted_filesystems = if limit_filesystem {
+        get_allowed_filesystems(top_level_names)
+    } else {
+        None
+    };
 
     for b in top_level_names.iter() {
         examine_dir(
             &b,
             apparent_size,
+            &restricted_filesystems,
             &mut inodes,
             &mut data,
             &mut permissions,
@@ -88,6 +96,16 @@ pub fn get_dir_tree(
     (permissions == 0, data)
 }
 
+fn get_allowed_filesystems(top_level_names: &HashSet<String>) -> Option<HashSet<u64>> {
+    let mut limit_filesystems: HashSet<u64> = HashSet::new();
+    for file_name in top_level_names.iter() {
+        if let Some(a) = get_filesystem(file_name) {
+            limit_filesystems.insert(a);
+        }
+    }
+    Some(limit_filesystems)
+}
+
 pub fn strip_end_slash(mut new_name: &str) -> &str {
     while (new_name.ends_with('/') || new_name.ends_with("/.")) && new_name.len() > 1 {
         new_name = &new_name[..new_name.len() - 1];
@@ -98,6 +116,7 @@ pub fn strip_end_slash(mut new_name: &str) -> &str {
 fn examine_dir(
     top_dir: &str,
     apparent_size: bool,
+    restricted_filesystems: &Option<HashSet<u64>>,
     inodes: &mut HashSet<(u64, u64)>,
     data: &mut HashMap<String, u64>,
     file_count_no_permission: &mut u64,
@@ -117,6 +136,16 @@ fn examine_dir(
                 Some((size, maybe_inode)) => {
                     if !apparent_size {
                         if let Some(inode_dev_pair) = maybe_inode {
+                            // Ignore files on different devices (if flag applied)
+                            if restricted_filesystems.is_some()
+                                && !restricted_filesystems
+                                    .as_ref()
+                                    .unwrap()
+                                    .contains(&inode_dev_pair.1)
+                            {
+                                continue;
+                            }
+                            // Ignore files already visited or symlinked
                             if inodes.contains(&inode_dev_pair) {
                                 continue;
                             }
@@ -128,7 +157,7 @@ fn examine_dir(
                         // This is required due to bug in Jwalk that adds '/' to all sub dir lists
                         // see: https://github.com/jessegrosjean/jwalk/issues/13
                         if path_name.to_string_lossy() == "/" && top_dir != "/" {
-                            continue
+                            continue;
                         }
                         let path_name = path_name.to_string_lossy();
                         let s = data.entry(path_name.to_string()).or_insert(0);

src/utils/platform.rs

@@ -1,4 +1,5 @@
 use jwalk::DirEntry;
+use std::fs;
 
 #[cfg(target_family = "unix")]
 fn get_block_size() -> u64 {
@@ -20,7 +21,16 @@ pub fn get_metadata(d: &DirEntry, use_apparent_size: bool) -> Option<(u64, Optio
     })
 }
 
-#[cfg(not(target_family = "unix"))]
+#[cfg(target_family = "windows")]
+pub fn get_metadata(d: &DirEntry, use_apparent_size: bool) -> Option<(u64, Option<(u64, u64)>)> {
+    use std::os::windows::fs::MetadataExt;
+    d.metadata.as_ref().unwrap().as_ref().ok().map(|md| {
+        let windows_equivalent_of_inode = Some((md.file_index(), md.volume_serial_number()));
+        (md.file_size(), windows_equivalent_of_inode)
+    })
+}
+
+#[cfg(all(not(target_family = "windows"), not(target_family = "unix")))]
 pub fn get_metadata(d: &DirEntry, _apparent: bool) -> Option<(u64, Option<(u64, u64)>)> {
     d.metadata
         .as_ref()
@@ -29,3 +39,22 @@ pub fn get_metadata(d: &DirEntry, _apparent: bool) -> Option<(u64, Option<(u64,
         .ok()
         .map(|md| (md.len(), None))
 }
+
+#[cfg(target_family = "unix")]
+pub fn get_filesystem(file_path: &str) -> Option<u64> {
+    use std::os::unix::fs::MetadataExt;
+    let metadata = fs::metadata(file_path).unwrap();
+    Some(metadata.dev())
+}
+
+#[cfg(target_family = "windows")]
+pub fn get_device(file_path: &str) -> Option<u64> {
+    use std::os::windows::fs::MetadataExt;
+    let metadata = fs::metadata(file_path).unwrap();
+    Some(metadata.volume_serial_number())
+}
+
+#[cfg(all(not(target_family = "windows"), not(target_family = "unix")))]
+pub fn get_device(file_path: &str) -> Option<u64> {
+    None
+}