Wire up modes

Prior to this commit, modes did nothing since they were not populated.
After this commit, they are populated in the index, and that information
is used to specify modes on the created files.

Closes #13.

src/repo/pack.rs

@@ -8,6 +8,7 @@ use std::{
     fs::{self, Permissions},
     io,
     io::{BufReader, Read, Write},
+    os::unix::prelude::PermissionsExt,
     path::{Path, PathBuf},
 };
 use std::{fmt::Display, str::FromStr};
@@ -548,7 +549,7 @@ fn assign_to_frames(
             ObjectMetadata {
                 offset: local_offset, // Replace global offset -> local offset
                 size: entry.metadata.size,
-                mode: None,
+                mode: entry.metadata.mode,
             },
         );
         frames[frame_index].push(local_entry);
@@ -662,9 +663,15 @@ fn extract_files(
             path_buf.clear();
             path_buf.push(&output_dir);
             path_buf.push(&entry.path);
-            stats.write_time += measure_ok(|| write_object(&buf[..], &path_buf, None))?
-                .0
-                .as_secs_f64();
+            stats.write_time += measure_ok(|| {
+                write_object(
+                    &buf[..],
+                    &path_buf,
+                    entry.metadata.mode.map(Permissions::from_mode),
+                )
+            })?
+            .0
+            .as_secs_f64();
         }
 
         Ok(())

src/repo/repository.rs

@@ -5,8 +5,10 @@ use super::{constants::*, pack::IdError};
 
 use std::{
     collections::{HashMap, HashSet},
-    fs, io,
+    fs::{self, File, Permissions},
+    io,
     io::{Read, Write},
+    os::unix::prelude::PermissionsExt,
     path::{Path, PathBuf},
     str::FromStr,
     sync::atomic::{AtomicBool, Ordering},
@@ -581,7 +583,11 @@ impl Repository {
         let threads = num_cpus::get();
 
         let pack_entries = run_in_parallel(threads, files.into_iter(), |file_path| {
-            let buf = fs::read(&file_path)?;
+            let mut fd = File::open(&file_path)?;
+            let mut buf = vec![];
+            fd.read_to_end(&mut buf)?;
+            let mode = fd.metadata()?.permissions().mode();
+            drop(fd);
             let mut checksum = [0u8; 20];
             let mut hasher = Sha1::new();
             hasher.input(&buf);
@@ -594,7 +600,7 @@ impl Repository {
                 ObjectMetadata {
                     offset: LOOSE_OBJECT_OFFSET,
                     size: buf.len() as u64,
-                    mode: None,
+                    mode: Some(mode),
                 },
             ))
         })
@@ -1020,6 +1026,12 @@ impl Repository {
                     ),
                 )
             })?;
+
+            entry
+                .metadata
+                .mode
+                .map(Permissions::from_mode)
+                .map_or(Ok(()), |p| fs::set_permissions(&dest_path, p))?;
         }
 
         if verify {