#![cfg_attr(windows, feature(windows_by_handle))]
use std::collections::HashMap;
#[derive(Debug, Default, Clone)]
pub struct InodeFilter {
inner: HashMap<u64, u64>,
}
impl InodeFilter {
#[cfg(unix)]
pub fn add(&mut self, metadata: &std::fs::Metadata) -> bool {
use std::os::unix::fs::MetadataExt;
self.add_inode(metadata.ino(), metadata.nlink())
}
#[cfg(windows)]
pub fn add(&mut self, metadata: &std::fs::Metadata) -> bool {
use std::os::windows::fs::MetadataExt;
if let (Some(inode), Some(nlinks)) = (metadata.file_index(), metadata.number_of_links()) {
self.add_inode(inode, nlinks as u64)
} else {
true
}
}
#[cfg(not(any(unix, windows)))]
pub fn add(&mut self, metadata: &std::fs::Metadata) -> bool {
true
}
pub fn add_inode(&mut self, inode: u64, nlinks: u64) -> bool {
if nlinks <= 1 {
return true;
}
match self.inner.get_mut(&inode) {
Some(count) => {
*count -= 1;
if *count == 0 {
self.inner.remove(&inode);
}
false
}
None => {
self.inner.insert(inode, nlinks - 1);
true
}
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn it_filters_inodes() {
let mut inodes = InodeFilter::default();
assert!(inodes.add_inode(1, 2));
assert!(!inodes.add_inode(1, 2));
assert!(inodes.add_inode(1, 3));
assert!(!inodes.add_inode(1, 3));
assert!(!inodes.add_inode(1, 3));
assert!(inodes.add_inode(1, 1));
assert!(inodes.add_inode(1, 1));
}
}