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-rw-r--r--vendor/google.golang.org/api/gensupport/buffer.go77
1 files changed, 77 insertions, 0 deletions
diff --git a/vendor/google.golang.org/api/gensupport/buffer.go b/vendor/google.golang.org/api/gensupport/buffer.go
new file mode 100644
index 0000000..4b8ec14
--- /dev/null
+++ b/vendor/google.golang.org/api/gensupport/buffer.go
@@ -0,0 +1,77 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gensupport
+
+import (
+ "bytes"
+ "io"
+
+ "google.golang.org/api/googleapi"
+)
+
+// ResumableBuffer buffers data from an io.Reader to support uploading media in retryable chunks.
+type ResumableBuffer struct {
+ media io.Reader
+
+ chunk []byte // The current chunk which is pending upload. The capacity is the chunk size.
+ err error // Any error generated when populating chunk by reading media.
+
+ // The absolute position of chunk in the underlying media.
+ off int64
+}
+
+func NewResumableBuffer(media io.Reader, chunkSize int) *ResumableBuffer {
+ return &ResumableBuffer{media: media, chunk: make([]byte, 0, chunkSize)}
+}
+
+// Chunk returns the current buffered chunk, the offset in the underlying media
+// from which the chunk is drawn, and the size of the chunk.
+// Successive calls to Chunk return the same chunk between calls to Next.
+func (rb *ResumableBuffer) Chunk() (chunk io.Reader, off int64, size int, err error) {
+ // There may already be data in chunk if Next has not been called since the previous call to Chunk.
+ if rb.err == nil && len(rb.chunk) == 0 {
+ rb.err = rb.loadChunk()
+ }
+ return bytes.NewReader(rb.chunk), rb.off, len(rb.chunk), rb.err
+}
+
+// loadChunk will read from media into chunk, up to the capacity of chunk.
+func (rb *ResumableBuffer) loadChunk() error {
+ bufSize := cap(rb.chunk)
+ rb.chunk = rb.chunk[:bufSize]
+
+ read := 0
+ var err error
+ for err == nil && read < bufSize {
+ var n int
+ n, err = rb.media.Read(rb.chunk[read:])
+ read += n
+ }
+ rb.chunk = rb.chunk[:read]
+ return err
+}
+
+// Next advances to the next chunk, which will be returned by the next call to Chunk.
+// Calls to Next without a corresponding prior call to Chunk will have no effect.
+func (rb *ResumableBuffer) Next() {
+ rb.off += int64(len(rb.chunk))
+ rb.chunk = rb.chunk[0:0]
+}
+
+type readerTyper struct {
+ io.Reader
+ googleapi.ContentTyper
+}
+
+// ReaderAtToReader adapts a ReaderAt to be used as a Reader.
+// If ra implements googleapi.ContentTyper, then the returned reader
+// will also implement googleapi.ContentTyper, delegating to ra.
+func ReaderAtToReader(ra io.ReaderAt, size int64) io.Reader {
+ r := io.NewSectionReader(ra, 0, size)
+ if typer, ok := ra.(googleapi.ContentTyper); ok {
+ return readerTyper{r, typer}
+ }
+ return r
+}