48 lines
1,002 B
Go
48 lines
1,002 B
Go
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package ctxio
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import (
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"context"
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"sync"
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)
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type ReaderReaderAtWrapper struct {
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mu sync.Mutex
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rat ReaderAt
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offset int64
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}
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func NewReaderReaderAtWrapper(rat ReaderAt) *ReaderReaderAtWrapper {
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return &ReaderReaderAtWrapper{
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rat: rat,
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}
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}
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var _ Reader = (*ReaderReaderAtWrapper)(nil)
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var _ ReaderAt = (*ReaderReaderAtWrapper)(nil)
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var _ Closer = (*ReaderReaderAtWrapper)(nil)
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// Read implements Reader.
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func (r *ReaderReaderAtWrapper) Read(ctx context.Context, p []byte) (n int, err error) {
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r.mu.Lock()
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defer r.mu.Unlock()
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n, err = r.rat.ReadAt(ctx, p, r.offset)
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r.offset += int64(n)
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return n, err
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}
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// ReadAt implements ReaderAt.
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func (r *ReaderReaderAtWrapper) ReadAt(ctx context.Context, p []byte, off int64) (n int, err error) {
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return r.rat.ReadAt(ctx, p, off)
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}
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// Close implements Closer.
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func (r *ReaderReaderAtWrapper) Close(ctx context.Context) (err error) {
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if c, ok := r.rat.(Closer); ok {
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err = c.Close(ctx)
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if err != nil {
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return err
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}
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}
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return nil
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}
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