[WIP] hardlinks - blocked on tar-rs support

the8472 · Mar 18, 2021 · 8ead07f · 8ead07f
1 parent a20723e
commit 8ead07f
Showing 1 changed file with 21 additions and 2 deletions.
diff --git a/src/main.rs b/src/main.rs
@@ -23,12 +23,14 @@ extern crate tar;
 extern crate nix;
 
 use std::io::*;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use clap::{Arg, App};
 use platter_walk::*;
 use std::fs::File;
-use tar::{Builder, Header, HeaderMode};
+use tar::{Builder, Header, HeaderMode, EntryType};
 use std::os::unix::io::{FromRawFd, AsRawFd};
+use std::collections::HashMap;
+use std::os::linux::fs::MetadataExt;
 
 #[derive(Debug, Error)]
 enum CliError {
@@ -86,6 +88,7 @@ fn process_args() -> std::result::Result<(), CliError> {
     }
 
     let mut builder = Builder::new(BufWriter::new(out));
+    let mut hardlinks: HashMap<(u64, u64), PathBuf> = HashMap::new();
 
     loop {
         match reap.next() {
@@ -96,6 +99,22 @@ fn process_args() -> std::result::Result<(), CliError> {
             Some(Ok(mut reader)) => {
                 let mut p = reader.path().to_owned();
                 let meta = reader.metadata();
+
+                if meta.file_type().is_file() && meta.st_nlink() > 1 {
+                    let val = hardlinks.entry((meta.st_dev(), meta.st_ino())).or_insert(p.clone());
+                    if val != &p {
+                        // hardlinked file we already visited
+                        let mut header = Header::new_gnu();
+                        header.set_metadata_in_mode(&meta, HeaderMode::Deterministic);
+                        header.set_entry_type(EntryType::hard_link());
+                        header.set_link_name(val).unwrap();
+                        header.set_cksum();
+                        // &p, std::io::empty()
+
+                        continue;
+                    }
+                }
+
                 //writeln!(std::io::stderr(), "before strip {}", p.to_string_lossy())?;
                 for path in &starting_points {
                     if p.starts_with(path) {