039582f49e
Turn BytesPipe's Read and Write functions into blocking, goroutine-safe functions. Add a CloseWithError function to propagate an error code to the Read function. Adjust tests to work with the blocking Read and Write functions. Remove BufReader, since now its users can use BytesPipe directly. Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
83 lines
1.5 KiB
Go
83 lines
1.5 KiB
Go
package ioutils
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import (
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"crypto/sha256"
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"encoding/hex"
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"io"
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)
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type readCloserWrapper struct {
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io.Reader
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closer func() error
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}
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func (r *readCloserWrapper) Close() error {
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return r.closer()
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}
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// NewReadCloserWrapper returns a new io.ReadCloser.
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func NewReadCloserWrapper(r io.Reader, closer func() error) io.ReadCloser {
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return &readCloserWrapper{
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Reader: r,
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closer: closer,
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}
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}
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type readerErrWrapper struct {
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reader io.Reader
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closer func()
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}
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func (r *readerErrWrapper) Read(p []byte) (int, error) {
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n, err := r.reader.Read(p)
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if err != nil {
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r.closer()
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}
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return n, err
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}
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// NewReaderErrWrapper returns a new io.Reader.
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func NewReaderErrWrapper(r io.Reader, closer func()) io.Reader {
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return &readerErrWrapper{
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reader: r,
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closer: closer,
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}
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}
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// HashData returns the sha256 sum of src.
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func HashData(src io.Reader) (string, error) {
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h := sha256.New()
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if _, err := io.Copy(h, src); err != nil {
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return "", err
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}
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return "sha256:" + hex.EncodeToString(h.Sum(nil)), nil
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}
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// OnEOFReader wraps a io.ReadCloser and a function
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// the function will run at the end of file or close the file.
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type OnEOFReader struct {
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Rc io.ReadCloser
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Fn func()
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}
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func (r *OnEOFReader) Read(p []byte) (n int, err error) {
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n, err = r.Rc.Read(p)
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if err == io.EOF {
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r.runFunc()
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}
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return
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}
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// Close closes the file and run the function.
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func (r *OnEOFReader) Close() error {
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err := r.Rc.Close()
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r.runFunc()
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return err
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}
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func (r *OnEOFReader) runFunc() {
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if fn := r.Fn; fn != nil {
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fn()
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r.Fn = nil
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}
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}
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