mirror of
https://github.com/cwinfo/matterbridge.git
synced 2024-12-30 19:45:40 +00:00
300 lines
6.6 KiB
Go
300 lines
6.6 KiB
Go
// Copyright 2013 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package japanese
|
|
|
|
import (
|
|
"unicode/utf8"
|
|
|
|
"golang.org/x/text/encoding"
|
|
"golang.org/x/text/encoding/internal"
|
|
"golang.org/x/text/encoding/internal/identifier"
|
|
"golang.org/x/text/transform"
|
|
)
|
|
|
|
// ISO2022JP is the ISO-2022-JP encoding.
|
|
var ISO2022JP encoding.Encoding = &iso2022JP
|
|
|
|
var iso2022JP = internal.Encoding{
|
|
internal.FuncEncoding{iso2022JPNewDecoder, iso2022JPNewEncoder},
|
|
"ISO-2022-JP",
|
|
identifier.ISO2022JP,
|
|
}
|
|
|
|
func iso2022JPNewDecoder() transform.Transformer {
|
|
return new(iso2022JPDecoder)
|
|
}
|
|
|
|
func iso2022JPNewEncoder() transform.Transformer {
|
|
return new(iso2022JPEncoder)
|
|
}
|
|
|
|
const (
|
|
asciiState = iota
|
|
katakanaState
|
|
jis0208State
|
|
jis0212State
|
|
)
|
|
|
|
const asciiEsc = 0x1b
|
|
|
|
type iso2022JPDecoder int
|
|
|
|
func (d *iso2022JPDecoder) Reset() {
|
|
*d = asciiState
|
|
}
|
|
|
|
func (d *iso2022JPDecoder) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
|
|
r, size := rune(0), 0
|
|
for ; nSrc < len(src); nSrc += size {
|
|
c0 := src[nSrc]
|
|
if c0 >= utf8.RuneSelf {
|
|
r, size = '\ufffd', 1
|
|
goto write
|
|
}
|
|
|
|
if c0 == asciiEsc {
|
|
if nSrc+2 >= len(src) {
|
|
if !atEOF {
|
|
return nDst, nSrc, transform.ErrShortSrc
|
|
}
|
|
// TODO: is it correct to only skip 1??
|
|
r, size = '\ufffd', 1
|
|
goto write
|
|
}
|
|
size = 3
|
|
c1 := src[nSrc+1]
|
|
c2 := src[nSrc+2]
|
|
switch {
|
|
case c1 == '$' && (c2 == '@' || c2 == 'B'): // 0x24 {0x40, 0x42}
|
|
*d = jis0208State
|
|
continue
|
|
case c1 == '$' && c2 == '(': // 0x24 0x28
|
|
if nSrc+3 >= len(src) {
|
|
if !atEOF {
|
|
return nDst, nSrc, transform.ErrShortSrc
|
|
}
|
|
r, size = '\ufffd', 1
|
|
goto write
|
|
}
|
|
size = 4
|
|
if src[nSrc+3] == 'D' {
|
|
*d = jis0212State
|
|
continue
|
|
}
|
|
case c1 == '(' && (c2 == 'B' || c2 == 'J'): // 0x28 {0x42, 0x4A}
|
|
*d = asciiState
|
|
continue
|
|
case c1 == '(' && c2 == 'I': // 0x28 0x49
|
|
*d = katakanaState
|
|
continue
|
|
}
|
|
r, size = '\ufffd', 1
|
|
goto write
|
|
}
|
|
|
|
switch *d {
|
|
case asciiState:
|
|
r, size = rune(c0), 1
|
|
|
|
case katakanaState:
|
|
if c0 < 0x21 || 0x60 <= c0 {
|
|
r, size = '\ufffd', 1
|
|
goto write
|
|
}
|
|
r, size = rune(c0)+(0xff61-0x21), 1
|
|
|
|
default:
|
|
if c0 == 0x0a {
|
|
*d = asciiState
|
|
r, size = rune(c0), 1
|
|
goto write
|
|
}
|
|
if nSrc+1 >= len(src) {
|
|
if !atEOF {
|
|
return nDst, nSrc, transform.ErrShortSrc
|
|
}
|
|
r, size = '\ufffd', 1
|
|
goto write
|
|
}
|
|
size = 2
|
|
c1 := src[nSrc+1]
|
|
i := int(c0-0x21)*94 + int(c1-0x21)
|
|
if *d == jis0208State && i < len(jis0208Decode) {
|
|
r = rune(jis0208Decode[i])
|
|
} else if *d == jis0212State && i < len(jis0212Decode) {
|
|
r = rune(jis0212Decode[i])
|
|
} else {
|
|
r = '\ufffd'
|
|
goto write
|
|
}
|
|
if r == 0 {
|
|
r = '\ufffd'
|
|
}
|
|
}
|
|
|
|
write:
|
|
if nDst+utf8.RuneLen(r) > len(dst) {
|
|
return nDst, nSrc, transform.ErrShortDst
|
|
}
|
|
nDst += utf8.EncodeRune(dst[nDst:], r)
|
|
}
|
|
return nDst, nSrc, err
|
|
}
|
|
|
|
type iso2022JPEncoder int
|
|
|
|
func (e *iso2022JPEncoder) Reset() {
|
|
*e = asciiState
|
|
}
|
|
|
|
func (e *iso2022JPEncoder) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
|
|
r, size := rune(0), 0
|
|
for ; nSrc < len(src); nSrc += size {
|
|
r = rune(src[nSrc])
|
|
|
|
// Decode a 1-byte rune.
|
|
if r < utf8.RuneSelf {
|
|
size = 1
|
|
|
|
} else {
|
|
// Decode a multi-byte rune.
|
|
r, size = utf8.DecodeRune(src[nSrc:])
|
|
if size == 1 {
|
|
// All valid runes of size 1 (those below utf8.RuneSelf) were
|
|
// handled above. We have invalid UTF-8 or we haven't seen the
|
|
// full character yet.
|
|
if !atEOF && !utf8.FullRune(src[nSrc:]) {
|
|
err = transform.ErrShortSrc
|
|
break
|
|
}
|
|
}
|
|
|
|
// func init checks that the switch covers all tables.
|
|
//
|
|
// http://encoding.spec.whatwg.org/#iso-2022-jp says that "the index jis0212
|
|
// is not used by the iso-2022-jp encoder due to lack of widespread support".
|
|
//
|
|
// TODO: do we have to special-case U+00A5 and U+203E, as per
|
|
// http://encoding.spec.whatwg.org/#iso-2022-jp
|
|
// Doing so would mean that "\u00a5" would not be preserved
|
|
// after an encode-decode round trip.
|
|
switch {
|
|
case encode0Low <= r && r < encode0High:
|
|
if r = rune(encode0[r-encode0Low]); r>>tableShift == jis0208 {
|
|
goto writeJIS
|
|
}
|
|
case encode1Low <= r && r < encode1High:
|
|
if r = rune(encode1[r-encode1Low]); r>>tableShift == jis0208 {
|
|
goto writeJIS
|
|
}
|
|
case encode2Low <= r && r < encode2High:
|
|
if r = rune(encode2[r-encode2Low]); r>>tableShift == jis0208 {
|
|
goto writeJIS
|
|
}
|
|
case encode3Low <= r && r < encode3High:
|
|
if r = rune(encode3[r-encode3Low]); r>>tableShift == jis0208 {
|
|
goto writeJIS
|
|
}
|
|
case encode4Low <= r && r < encode4High:
|
|
if r = rune(encode4[r-encode4Low]); r>>tableShift == jis0208 {
|
|
goto writeJIS
|
|
}
|
|
case encode5Low <= r && r < encode5High:
|
|
if 0xff61 <= r && r < 0xffa0 {
|
|
goto writeKatakana
|
|
}
|
|
if r = rune(encode5[r-encode5Low]); r>>tableShift == jis0208 {
|
|
goto writeJIS
|
|
}
|
|
}
|
|
|
|
// Switch back to ASCII state in case of error so that an ASCII
|
|
// replacement character can be written in the correct state.
|
|
if *e != asciiState {
|
|
if nDst+3 > len(dst) {
|
|
err = transform.ErrShortDst
|
|
break
|
|
}
|
|
*e = asciiState
|
|
dst[nDst+0] = asciiEsc
|
|
dst[nDst+1] = '('
|
|
dst[nDst+2] = 'B'
|
|
nDst += 3
|
|
}
|
|
err = internal.ErrASCIIReplacement
|
|
break
|
|
}
|
|
|
|
if *e != asciiState {
|
|
if nDst+4 > len(dst) {
|
|
err = transform.ErrShortDst
|
|
break
|
|
}
|
|
*e = asciiState
|
|
dst[nDst+0] = asciiEsc
|
|
dst[nDst+1] = '('
|
|
dst[nDst+2] = 'B'
|
|
nDst += 3
|
|
} else if nDst >= len(dst) {
|
|
err = transform.ErrShortDst
|
|
break
|
|
}
|
|
dst[nDst] = uint8(r)
|
|
nDst++
|
|
continue
|
|
|
|
writeJIS:
|
|
if *e != jis0208State {
|
|
if nDst+5 > len(dst) {
|
|
err = transform.ErrShortDst
|
|
break
|
|
}
|
|
*e = jis0208State
|
|
dst[nDst+0] = asciiEsc
|
|
dst[nDst+1] = '$'
|
|
dst[nDst+2] = 'B'
|
|
nDst += 3
|
|
} else if nDst+2 > len(dst) {
|
|
err = transform.ErrShortDst
|
|
break
|
|
}
|
|
dst[nDst+0] = 0x21 + uint8(r>>codeShift)&codeMask
|
|
dst[nDst+1] = 0x21 + uint8(r)&codeMask
|
|
nDst += 2
|
|
continue
|
|
|
|
writeKatakana:
|
|
if *e != katakanaState {
|
|
if nDst+4 > len(dst) {
|
|
err = transform.ErrShortDst
|
|
break
|
|
}
|
|
*e = katakanaState
|
|
dst[nDst+0] = asciiEsc
|
|
dst[nDst+1] = '('
|
|
dst[nDst+2] = 'I'
|
|
nDst += 3
|
|
} else if nDst >= len(dst) {
|
|
err = transform.ErrShortDst
|
|
break
|
|
}
|
|
dst[nDst] = uint8(r - (0xff61 - 0x21))
|
|
nDst++
|
|
continue
|
|
}
|
|
if atEOF && err == nil && *e != asciiState {
|
|
if nDst+3 > len(dst) {
|
|
err = transform.ErrShortDst
|
|
} else {
|
|
*e = asciiState
|
|
dst[nDst+0] = asciiEsc
|
|
dst[nDst+1] = '('
|
|
dst[nDst+2] = 'B'
|
|
nDst += 3
|
|
}
|
|
}
|
|
return nDst, nSrc, err
|
|
}
|