fix for stream reader

fix https://github.com/seaweedfs/seaweedfs/issues/4112

weed/filer/stream.go

@@ -187,6 +187,7 @@ func ReadAll(buffer []byte, masterClient *wdclient.MasterClient, chunks []*filer
 
 // ----------------  ChunkStreamReader ----------------------------------
 type ChunkStreamReader struct {
+	head         *Interval[*ChunkView]
 	chunkView    *Interval[*ChunkView]
 	totalSize    int64
 	logicOffset  int64
@@ -211,6 +212,7 @@ func doNewChunkStreamReader(lookupFileIdFn wdclient.LookupFileIdFunctionType, ch
 	}
 
 	return &ChunkStreamReader{
+		head:         chunkViews.Front(),
 		chunkView:    chunkViews.Front(),
 		lookupFileId: lookupFileIdFn,
 		totalSize:    totalSize,
@@ -309,15 +311,20 @@ func (c *ChunkStreamReader) prepareBufferFor(offset int64) (err error) {
 	chunk := c.chunkView.Value
 	if insideChunk(offset, chunk) {
 		if c.isBufferEmpty() || c.bufferOffset != chunk.ViewOffset {
-			if err = c.fetchChunkToBuffer(chunk); err != nil {
-				return
-			}
+			return c.fetchChunkToBuffer(chunk)
 		}
 	} else {
-		// glog.Fatalf("unexpected3 offset %d in %s [%d,%d)", offset, chunk.FileId, chunk.ViewOffset, chunk.ViewOffset+int64(chunk.ViewSize))
-		return fmt.Errorf("unexpected3 offset %d in %s [%d,%d)", offset, chunk.FileId, chunk.ViewOffset, chunk.ViewOffset+int64(chunk.ViewSize))
+		for p := c.head; p != nil; p = p.Next {
+			chunk = p.Value
+			if insideChunk(offset, chunk) {
+				if c.isBufferEmpty() || c.bufferOffset != chunk.ViewOffset {
+					return c.fetchChunkToBuffer(chunk)
+				}
+			}
+		}
 	}
-	return
+
+	return io.EOF
 }
 
 func (c *ChunkStreamReader) fetchChunkToBuffer(chunkView *ChunkView) error {