61 lines
1.2 KiB
Go
61 lines
1.2 KiB
Go
package message
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import (
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"encoding/base64"
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"fmt"
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"io"
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"mime/quotedprintable"
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"strings"
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"github.com/emersion/go-textwrapper"
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)
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type unknownEncodingError struct {
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error
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}
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func isUnknownEncoding(err error) bool {
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_, ok := err.(unknownEncodingError)
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return ok
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}
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func encodingReader(enc string, r io.Reader) (io.Reader, error) {
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var dec io.Reader
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switch strings.ToLower(enc) {
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case "quoted-printable":
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dec = quotedprintable.NewReader(r)
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case "base64":
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dec = base64.NewDecoder(base64.StdEncoding, r)
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case "7bit", "8bit", "binary", "":
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dec = r
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default:
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return nil, fmt.Errorf("unhandled encoding %q", enc)
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}
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return dec, nil
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}
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type nopCloser struct {
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io.Writer
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}
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func (nopCloser) Close() error {
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return nil
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}
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func encodingWriter(enc string, w io.Writer) (io.WriteCloser, error) {
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var wc io.WriteCloser
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switch strings.ToLower(enc) {
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case "quoted-printable":
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wc = quotedprintable.NewWriter(w)
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case "base64":
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wc = base64.NewEncoder(base64.StdEncoding, textwrapper.NewRFC822(w))
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case "7bit", "8bit":
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wc = nopCloser{textwrapper.New(w, "\r\n", 1000)}
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case "binary", "":
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wc = nopCloser{w}
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default:
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return nil, fmt.Errorf("unhandled encoding %q", enc)
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}
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return wc, nil
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}
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