forked from lug/matterbridge
66 lines
1.3 KiB
Go
66 lines
1.3 KiB
Go
package charset
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import (
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"bytes"
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"fmt"
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"unicode/utf8"
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)
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func init() {
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registerClass("ascii", fromASCII, toASCII)
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}
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const errorByte = '?'
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type translateFromASCII bool
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type codePointError struct {
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i int
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cp rune
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charset string
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}
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func (e *codePointError) Error() string {
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return fmt.Sprintf("Parse error at index %d: Code point %d is undefined in %s", e.i, e.cp, e.charset)
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}
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func (strict translateFromASCII) Translate(data []byte, eof bool) (int, []byte, error) {
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buf := bytes.NewBuffer(make([]byte, 0, len(data)))
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for i, c := range data {
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if c > 0 && c < 128 {
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buf.WriteByte(c)
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if c < 32 && c != 10 && c != 13 && c != 9 {
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// badly formed
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}
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} else {
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if strict {
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return 0, nil, &codePointError{i, rune(c), "US-ASCII"}
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}
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buf.WriteRune(utf8.RuneError)
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}
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}
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return len(data), buf.Bytes(), nil
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}
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type translateToASCII bool
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func (strict translateToASCII) Translate(data []byte, eof bool) (int, []byte, error) {
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buf := bytes.NewBuffer(make([]byte, 0, len(data)))
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for _, c := range data {
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if c > 0 && c < 128 {
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buf.WriteByte(c)
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} else {
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buf.WriteByte(errorByte)
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}
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}
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return len(data), buf.Bytes(), nil
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}
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func fromASCII(arg string) (Translator, error) {
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return new(translateFromASCII), nil
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}
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func toASCII(arg string) (Translator, error) {
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return new(translateToASCII), nil
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}
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