1 files changed, 85 insertions, 0 deletions
diff --git a/vendor/github.com/minio/minio-go/v7/hook-reader.go b/vendor/github.com/minio/minio-go/v7/hook-reader.go
new file mode 100644
index 00000000..f251c1e9
--- /dev/null
+++ b/vendor/github.com/minio/minio-go/v7/hook-reader.go
@@ -0,0 +1,85 @@
+/*
+ * MinIO Go Library for Amazon S3 Compatible Cloud Storage
+ * Copyright 2015-2017 MinIO, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package minio
+
+import (
+	"fmt"
+	"io"
+)
+
+// hookReader hooks additional reader in the source stream. It is
+// useful for making progress bars. Second reader is appropriately
+// notified about the exact number of bytes read from the primary
+// source on each Read operation.
+type hookReader struct {
+	source io.Reader
+	hook   io.Reader
+}
+
+// Seek implements io.Seeker. Seeks source first, and if necessary
+// seeks hook if Seek method is appropriately found.
+func (hr *hookReader) Seek(offset int64, whence int) (n int64, err error) {
+	// Verify for source has embedded Seeker, use it.
+	sourceSeeker, ok := hr.source.(io.Seeker)
+	if ok {
+		n, err = sourceSeeker.Seek(offset, whence)
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	// Verify if hook has embedded Seeker, use it.
+	hookSeeker, ok := hr.hook.(io.Seeker)
+	if ok {
+		var m int64
+		m, err = hookSeeker.Seek(offset, whence)
+		if err != nil {
+			return 0, err
+		}
+		if n != m {
+			return 0, fmt.Errorf("hook seeker seeked %d bytes, expected source %d bytes", m, n)
+		}
+	}
+	return n, nil
+}
+
+// Read implements io.Reader. Always reads from the source, the return
+// value 'n' number of bytes are reported through the hook. Returns
+// error for all non io.EOF conditions.
+func (hr *hookReader) Read(b []byte) (n int, err error) {
+	n, err = hr.source.Read(b)
+	if err != nil && err != io.EOF {
+		return n, err
+	}
+	// Progress the hook with the total read bytes from the source.
+	if _, herr := hr.hook.Read(b[:n]); herr != nil {
+		if herr != io.EOF {
+			return n, herr
+		}
+	}
+	return n, err
+}
+
+// newHook returns a io.ReadSeeker which implements hookReader that
+// reports the data read from the source to the hook.
+func newHook(source, hook io.Reader) io.Reader {
+	if hook == nil {
+		return source
+	}
+	return &hookReader{source, hook}
+}