1 files changed, 43 insertions, 0 deletions
diff --git a/src/traits.rs b/src/traits.rs
new file mode 100644
index 0000000..01708b8
--- /dev/null
+++ b/src/traits.rs
@@ -0,0 +1,43 @@
+use crate::error::{NtfsError, Result};
+use binread::io;
+use binread::io::{Read, Seek, SeekFrom};
+
+pub trait NtfsReadSeek {
+    fn read<T>(&mut self, fs: &mut T, buf: &mut [u8]) -> Result<usize>
+    where
+        T: Read + Seek;
+
+    fn read_exact<T>(&mut self, fs: &mut T, mut buf: &mut [u8]) -> Result<()>
+    where
+        T: Read + Seek,
+    {
+        // This implementation is taken from https://github.com/rust-lang/rust/blob/5662d9343f0696efcc38a1264656737c9f22d427/library/std/src/io/mod.rs
+        // It handles all corner cases properly and outputs the known `io` error messages.
+        while !buf.is_empty() {
+            match self.read(fs, buf) {
+                Ok(0) => break,
+                Ok(n) => {
+                    buf = &mut buf[n..];
+                }
+                Err(NtfsError::Io(e)) if e.kind() == io::ErrorKind::Interrupted => {}
+                Err(e) => return Err(e),
+            }
+        }
+
+        if !buf.is_empty() {
+            Err(NtfsError::Io(io::Error::new(
+                io::ErrorKind::UnexpectedEof,
+                "failed to fill whole buffer",
+            )))
+        } else {
+            Ok(())
+        }
+    }
+
+    fn seek<T>(&mut self, fs: &mut T, pos: SeekFrom) -> Result<u64>
+    where
+        T: Read + Seek;
+
+    /// See [`std::io::Seek::stream_position`].
+    fn stream_position(&mut self) -> Result<u64>;
+}