go-sample-webpage/vendor/github.com/lestrrat-go/jwx/jwe/compress.go

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2021-11-04 01:14:51 +00:00
package jwe
import (
"bytes"
"compress/flate"
"io/ioutil"
"github.com/lestrrat-go/jwx/internal/pool"
"github.com/lestrrat-go/jwx/jwa"
"github.com/pkg/errors"
)
func uncompress(plaintext []byte) ([]byte, error) {
return ioutil.ReadAll(flate.NewReader(bytes.NewReader(plaintext)))
}
func compress(plaintext []byte, alg jwa.CompressionAlgorithm) ([]byte, error) {
if alg == jwa.NoCompress {
return plaintext, nil
}
buf := pool.GetBytesBuffer()
defer pool.ReleaseBytesBuffer(buf)
w, _ := flate.NewWriter(buf, 1)
in := plaintext
for len(in) > 0 {
n, err := w.Write(in)
if err != nil {
return nil, errors.Wrap(err, `failed to write to compression writer`)
}
in = in[n:]
}
if err := w.Close(); err != nil {
return nil, errors.Wrap(err, "failed to close compression writer")
}
ret := make([]byte, buf.Len())
copy(ret, buf.Bytes())
return ret, nil
}