buffered_read: return empty buffer on eof

src/backup/archive_index.rs

@@ -231,6 +231,8 @@ impl <'a> crate::tools::BufferedReader for  BufferedArchiveReader<'a> {
 
     fn buffered_read(&mut self, offset: u64) -> Result<&[u8], Error> {
 
+        if offset == self.archive_size { return Ok(&self.read_buffer[0..0]); }
+
         let buffer_len = self.read_buffer.len();
         let index = self.index;
 

src/tools.rs

@@ -21,8 +21,9 @@ pub mod timer;
 /// `buffered_read`. It returns a reference to an internal buffer. The
 /// purpose of this traid is to avoid unnecessary data copies.
 pub trait BufferedReader {
-    /// This functions tries to fill the internal buffers, then returns
-    /// a reference to the available data.
+    /// This functions tries to fill the internal buffers, then
+    /// returns a reference to the available data. It returns an empty
+    /// buffer if `offset` points to the end of the file.
     fn buffered_read(&mut self, offset: u64) -> Result<&[u8], Error>;
 }