crossplane

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/*
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Copyright 2022 The Crossplane 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 xpkg
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import (
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	"compress/gzip"
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	"io"
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)
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var _ io.ReadCloser = &gzipReadCloser{}
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// gzipReadCloser reads compressed contents from a file.
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type gzipReadCloser struct {
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	rc   io.ReadCloser
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	gzip *gzip.Reader
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}
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// GzipReadCloser constructs a new gzipReadCloser from the passed file.
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func GzipReadCloser(rc io.ReadCloser) (io.ReadCloser, error) {
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	r, err := gzip.NewReader(rc)
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	if err != nil {
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		return nil, err
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	}
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	return &gzipReadCloser{
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		rc:   rc,
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		gzip: r,
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	}, nil
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}
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// Read calls the underlying gzip reader's Read method.
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func (g *gzipReadCloser) Read(p []byte) (n int, err error) {
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	return g.gzip.Read(p)
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}
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// Close first closes the gzip reader, then closes the underlying closer.
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func (g *gzipReadCloser) Close() error {
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	if err := g.gzip.Close(); err != nil {
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		_ = g.rc.Close()
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		return err
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	}
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	return g.rc.Close()
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}
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var _ io.ReadCloser = &teeReadCloser{}
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// teeReadCloser is a TeeReader that also closes the underlying writer.
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type teeReadCloser struct {
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	w io.WriteCloser
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	r io.ReadCloser
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	t io.Reader
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}
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// TeeReadCloser constructs a teeReadCloser from the passed reader and writer.
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func TeeReadCloser(r io.ReadCloser, w io.WriteCloser) io.ReadCloser {
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	return &teeReadCloser{
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		w: w,
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		r: r,
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		t: io.TeeReader(r, w),
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	}
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}
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// Read calls the underlying TeeReader Read method.
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func (t *teeReadCloser) Read(b []byte) (int, error) {
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	return t.t.Read(b)
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}
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// Close closes the underlying ReadCloser, then the Writer for the TeeReader.
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func (t *teeReadCloser) Close() error {
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	if err := t.r.Close(); err != nil {
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		_ = t.w.Close()
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		return err
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	}
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	return t.w.Close()
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}
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var _ io.ReadCloser = &joinedReadCloser{}
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// joinedReadCloster joins a reader and a closer. It is typically used in the
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// context of a ReadCloser being wrapped by a Reader.
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type joinedReadCloser struct {
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	r io.Reader
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	c io.Closer
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}
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// JoinedReadCloser constructs a new joinedReadCloser from the passed reader and
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// closer.
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func JoinedReadCloser(r io.Reader, c io.Closer) io.ReadCloser {
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	return &joinedReadCloser{
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		r: r,
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		c: c,
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	}
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}
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// Read calls the underlying reader Read method.
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func (r *joinedReadCloser) Read(b []byte) (int, error) {
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	return r.r.Read(b)
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}
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// Close closes the closer for the JoinedReadCloser.
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func (r *joinedReadCloser) Close() error {
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	return r.c.Close()
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}
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