bbe46b8c43
Signed-off-by: haoyun <yun.hao@daocloud.io> Co-authored-by: zounengren <zouyee1989@gmail.com>
68 lines
1.6 KiB
Go
68 lines
1.6 KiB
Go
/*
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Copyright The containerd Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package local
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import (
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"fmt"
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"os"
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"github.com/containerd/containerd/content"
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"github.com/containerd/containerd/errdefs"
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)
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// readerat implements io.ReaderAt in a completely stateless manner by opening
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// the referenced file for each call to ReadAt.
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type sizeReaderAt struct {
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size int64
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fp *os.File
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}
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// OpenReader creates ReaderAt from a file
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func OpenReader(p string) (content.ReaderAt, error) {
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fi, err := os.Stat(p)
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if err != nil {
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if !os.IsNotExist(err) {
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return nil, err
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}
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return nil, fmt.Errorf("blob not found: %w", errdefs.ErrNotFound)
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}
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fp, err := os.Open(p)
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if err != nil {
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if !os.IsNotExist(err) {
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return nil, err
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}
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return nil, fmt.Errorf("blob not found: %w", errdefs.ErrNotFound)
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}
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return sizeReaderAt{size: fi.Size(), fp: fp}, nil
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}
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func (ra sizeReaderAt) ReadAt(p []byte, offset int64) (int, error) {
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return ra.fp.ReadAt(p, offset)
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}
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func (ra sizeReaderAt) Size() int64 {
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return ra.size
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}
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func (ra sizeReaderAt) Close() error {
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return ra.fp.Close()
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}
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