added specific functions to AsyncFileReader trait so we know where we are wrt. caching

Author: feefladder

src/ifd.rs

@@ -779,7 +779,7 @@ impl ImageFileDirectory {
         let range = self
             .get_tile_byte_range(x, y)
             .ok_or(AsyncTiffError::General("Not a tiled TIFF".to_string()))?;
-        let compressed_bytes = reader.get_bytes(range).await?;
+        let compressed_bytes = reader.get_tile_bytes(range).await?;
         Ok(Tile {
             x,
             y,
@@ -810,7 +810,7 @@ impl ImageFileDirectory {
             .collect::<AsyncTiffResult<Vec<_>>>()?;
 
         // 2: Fetch using `get_ranges
-        let buffers = reader.get_byte_ranges(byte_ranges).await?;
+        let buffers = reader.get_tile_byte_ranges(byte_ranges).await?;
 
         // 3: Create tile objects
         let mut tiles = vec![];

src/reader.rs

@@ -52,6 +52,18 @@ pub trait AsyncFileReader: Debug + Send + Sync {
         }
         .boxed()
     }
+
+    /// Same as [`get_bytes`], but this function is called when retrieving
+    /// compressed tile data
+    fn get_tile_bytes(&self, range: Range<u64>) -> BoxFuture<'_, AsyncTiffResult<Bytes>> {
+        self.get_bytes(range)
+    }
+
+    /// Same as [`get_byte_ranges`], but this function is only called when retrieving
+    /// compressed tile data
+    fn get_tile_byte_ranges(&self, ranges: Vec<Range<u64>>) -> BoxFuture<'_, AsyncTiffResult<Vec<Bytes>>> {
+        self.get_byte_ranges(ranges)
+    }
 }
 
 /// This allows Box<dyn AsyncFileReader + '_> to be used as an AsyncFileReader,