containerd/services/content/reader.go
Derek McGowan e0136cc83f
Clear extra in content service reader after consumed
Avoid bugs where content can mistakenly be read from
extra after an EOF is returned.

Signed-off-by: Derek McGowan <derek@mcgstyle.net>
2017-05-19 11:37:40 -07:00

52 lines
876 B
Go

package content
import (
contentapi "github.com/containerd/containerd/api/services/content"
)
type remoteReader struct {
client contentapi.Content_ReadClient
extra []byte
}
func (rr *remoteReader) Read(p []byte) (n int, err error) {
n += copy(p, rr.extra)
if n >= len(p) {
if n <= len(rr.extra) {
rr.extra = rr.extra[n:]
} else {
rr.extra = rr.extra[:0]
}
return
}
rr.extra = rr.extra[:0]
p = p[n:]
for len(p) > 0 {
var resp *contentapi.ReadResponse
// fill our buffer up until we can fill p.
resp, err = rr.client.Recv()
if err != nil {
return
}
copied := copy(p, resp.Data)
n += copied
p = p[copied:]
if copied < len(p) {
continue
}
rr.extra = append(rr.extra, resp.Data[copied:]...)
}
return
}
// TODO(stevvooe): Implemente io.ReaderAt.
func (rr *remoteReader) Close() error {
return rr.client.CloseSend()
}