mirror of
https://github.com/octoleo/restic.git
synced 2024-12-30 13:40:36 +00:00
49 lines
1.2 KiB
Go
49 lines
1.2 KiB
Go
// Copyright 2017, Google
|
|
//
|
|
// 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 b2
|
|
|
|
import (
|
|
"io"
|
|
"sync"
|
|
)
|
|
|
|
type readerAt struct {
|
|
rs io.ReadSeeker
|
|
mu sync.Mutex
|
|
}
|
|
|
|
func (r *readerAt) ReadAt(p []byte, off int64) (int, error) {
|
|
r.mu.Lock()
|
|
defer r.mu.Unlock()
|
|
|
|
// ReadAt is supposed to preserve the offset.
|
|
cur, err := r.rs.Seek(0, io.SeekCurrent)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
defer func() { r.rs.Seek(cur, io.SeekStart) }()
|
|
|
|
if _, err := r.rs.Seek(off, io.SeekStart); err != nil {
|
|
return 0, err
|
|
}
|
|
return io.ReadFull(r.rs, p)
|
|
}
|
|
|
|
// wraps a ReadSeeker in a mutex to provite a ReaderAt how is this not in the
|
|
// io package?
|
|
func enReaderAt(rs io.ReadSeeker) io.ReaderAt {
|
|
return &readerAt{rs: rs}
|
|
}
|