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path: root/vendor/golang.org/x/text/encoding/unicode/unicode.go
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Diffstat (limited to 'vendor/golang.org/x/text/encoding/unicode/unicode.go')
-rw-r--r--vendor/golang.org/x/text/encoding/unicode/unicode.go434
1 files changed, 0 insertions, 434 deletions
diff --git a/vendor/golang.org/x/text/encoding/unicode/unicode.go b/vendor/golang.org/x/text/encoding/unicode/unicode.go
deleted file mode 100644
index 4850ff3..0000000
--- a/vendor/golang.org/x/text/encoding/unicode/unicode.go
+++ /dev/null
@@ -1,434 +0,0 @@
-// 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 unicode provides Unicode encodings such as UTF-16.
-package unicode // import "golang.org/x/text/encoding/unicode"
-
-import (
- "errors"
- "unicode/utf16"
- "unicode/utf8"
-
- "golang.org/x/text/encoding"
- "golang.org/x/text/encoding/internal"
- "golang.org/x/text/encoding/internal/identifier"
- "golang.org/x/text/internal/utf8internal"
- "golang.org/x/text/runes"
- "golang.org/x/text/transform"
-)
-
-// TODO: I think the Transformers really should return errors on unmatched
-// surrogate pairs and odd numbers of bytes. This is not required by RFC 2781,
-// which leaves it open, but is suggested by WhatWG. It will allow for all error
-// modes as defined by WhatWG: fatal, HTML and Replacement. This would require
-// the introduction of some kind of error type for conveying the erroneous code
-// point.
-
-// UTF8 is the UTF-8 encoding.
-var UTF8 encoding.Encoding = utf8enc
-
-var utf8enc = &internal.Encoding{
- &internal.SimpleEncoding{utf8Decoder{}, runes.ReplaceIllFormed()},
- "UTF-8",
- identifier.UTF8,
-}
-
-type utf8Decoder struct{ transform.NopResetter }
-
-func (utf8Decoder) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
- var pSrc int // point from which to start copy in src
- var accept utf8internal.AcceptRange
-
- // The decoder can only make the input larger, not smaller.
- n := len(src)
- if len(dst) < n {
- err = transform.ErrShortDst
- n = len(dst)
- atEOF = false
- }
- for nSrc < n {
- c := src[nSrc]
- if c < utf8.RuneSelf {
- nSrc++
- continue
- }
- first := utf8internal.First[c]
- size := int(first & utf8internal.SizeMask)
- if first == utf8internal.FirstInvalid {
- goto handleInvalid // invalid starter byte
- }
- accept = utf8internal.AcceptRanges[first>>utf8internal.AcceptShift]
- if nSrc+size > n {
- if !atEOF {
- // We may stop earlier than necessary here if the short sequence
- // has invalid bytes. Not checking for this simplifies the code
- // and may avoid duplicate computations in certain conditions.
- if err == nil {
- err = transform.ErrShortSrc
- }
- break
- }
- // Determine the maximal subpart of an ill-formed subsequence.
- switch {
- case nSrc+1 >= n || src[nSrc+1] < accept.Lo || accept.Hi < src[nSrc+1]:
- size = 1
- case nSrc+2 >= n || src[nSrc+2] < utf8internal.LoCB || utf8internal.HiCB < src[nSrc+2]:
- size = 2
- default:
- size = 3 // As we are short, the maximum is 3.
- }
- goto handleInvalid
- }
- if c = src[nSrc+1]; c < accept.Lo || accept.Hi < c {
- size = 1
- goto handleInvalid // invalid continuation byte
- } else if size == 2 {
- } else if c = src[nSrc+2]; c < utf8internal.LoCB || utf8internal.HiCB < c {
- size = 2
- goto handleInvalid // invalid continuation byte
- } else if size == 3 {
- } else if c = src[nSrc+3]; c < utf8internal.LoCB || utf8internal.HiCB < c {
- size = 3
- goto handleInvalid // invalid continuation byte
- }
- nSrc += size
- continue
-
- handleInvalid:
- // Copy the scanned input so far.
- nDst += copy(dst[nDst:], src[pSrc:nSrc])
-
- // Append RuneError to the destination.
- const runeError = "\ufffd"
- if nDst+len(runeError) > len(dst) {
- return nDst, nSrc, transform.ErrShortDst
- }
- nDst += copy(dst[nDst:], runeError)
-
- // Skip the maximal subpart of an ill-formed subsequence according to
- // the W3C standard way instead of the Go way. This Transform is
- // probably the only place in the text repo where it is warranted.
- nSrc += size
- pSrc = nSrc
-
- // Recompute the maximum source length.
- if sz := len(dst) - nDst; sz < len(src)-nSrc {
- err = transform.ErrShortDst
- n = nSrc + sz
- atEOF = false
- }
- }
- return nDst + copy(dst[nDst:], src[pSrc:nSrc]), nSrc, err
-}
-
-// UTF16 returns a UTF-16 Encoding for the given default endianness and byte
-// order mark (BOM) policy.
-//
-// When decoding from UTF-16 to UTF-8, if the BOMPolicy is IgnoreBOM then
-// neither BOMs U+FEFF nor noncharacters U+FFFE in the input stream will affect
-// the endianness used for decoding, and will instead be output as their
-// standard UTF-8 encodings: "\xef\xbb\xbf" and "\xef\xbf\xbe". If the BOMPolicy
-// is UseBOM or ExpectBOM a staring BOM is not written to the UTF-8 output.
-// Instead, it overrides the default endianness e for the remainder of the
-// transformation. Any subsequent BOMs U+FEFF or noncharacters U+FFFE will not
-// affect the endianness used, and will instead be output as their standard
-// UTF-8 encodings. For UseBOM, if there is no starting BOM, it will proceed
-// with the default Endianness. For ExpectBOM, in that case, the transformation
-// will return early with an ErrMissingBOM error.
-//
-// When encoding from UTF-8 to UTF-16, a BOM will be inserted at the start of
-// the output if the BOMPolicy is UseBOM or ExpectBOM. Otherwise, a BOM will not
-// be inserted. The UTF-8 input does not need to contain a BOM.
-//
-// There is no concept of a 'native' endianness. If the UTF-16 data is produced
-// and consumed in a greater context that implies a certain endianness, use
-// IgnoreBOM. Otherwise, use ExpectBOM and always produce and consume a BOM.
-//
-// In the language of https://www.unicode.org/faq/utf_bom.html#bom10, IgnoreBOM
-// corresponds to "Where the precise type of the data stream is known... the
-// BOM should not be used" and ExpectBOM corresponds to "A particular
-// protocol... may require use of the BOM".
-func UTF16(e Endianness, b BOMPolicy) encoding.Encoding {
- return utf16Encoding{config{e, b}, mibValue[e][b&bomMask]}
-}
-
-// mibValue maps Endianness and BOMPolicy settings to MIB constants. Note that
-// some configurations map to the same MIB identifier. RFC 2781 has requirements
-// and recommendations. Some of the "configurations" are merely recommendations,
-// so multiple configurations could match.
-var mibValue = map[Endianness][numBOMValues]identifier.MIB{
- BigEndian: [numBOMValues]identifier.MIB{
- IgnoreBOM: identifier.UTF16BE,
- UseBOM: identifier.UTF16, // BigEnding default is preferred by RFC 2781.
- // TODO: acceptBOM | strictBOM would map to UTF16BE as well.
- },
- LittleEndian: [numBOMValues]identifier.MIB{
- IgnoreBOM: identifier.UTF16LE,
- UseBOM: identifier.UTF16, // LittleEndian default is allowed and preferred on Windows.
- // TODO: acceptBOM | strictBOM would map to UTF16LE as well.
- },
- // ExpectBOM is not widely used and has no valid MIB identifier.
-}
-
-// All lists a configuration for each IANA-defined UTF-16 variant.
-var All = []encoding.Encoding{
- UTF8,
- UTF16(BigEndian, UseBOM),
- UTF16(BigEndian, IgnoreBOM),
- UTF16(LittleEndian, IgnoreBOM),
-}
-
-// BOMPolicy is a UTF-16 encoding's byte order mark policy.
-type BOMPolicy uint8
-
-const (
- writeBOM BOMPolicy = 0x01
- acceptBOM BOMPolicy = 0x02
- requireBOM BOMPolicy = 0x04
- bomMask BOMPolicy = 0x07
-
- // HACK: numBOMValues == 8 triggers a bug in the 1.4 compiler (cannot have a
- // map of an array of length 8 of a type that is also used as a key or value
- // in another map). See golang.org/issue/11354.
- // TODO: consider changing this value back to 8 if the use of 1.4.* has
- // been minimized.
- numBOMValues = 8 + 1
-
- // IgnoreBOM means to ignore any byte order marks.
- IgnoreBOM BOMPolicy = 0
- // Common and RFC 2781-compliant interpretation for UTF-16BE/LE.
-
- // UseBOM means that the UTF-16 form may start with a byte order mark, which
- // will be used to override the default encoding.
- UseBOM BOMPolicy = writeBOM | acceptBOM
- // Common and RFC 2781-compliant interpretation for UTF-16.
-
- // ExpectBOM means that the UTF-16 form must start with a byte order mark,
- // which will be used to override the default encoding.
- ExpectBOM BOMPolicy = writeBOM | acceptBOM | requireBOM
- // Used in Java as Unicode (not to be confused with Java's UTF-16) and
- // ICU's UTF-16,version=1. Not compliant with RFC 2781.
-
- // TODO (maybe): strictBOM: BOM must match Endianness. This would allow:
- // - UTF-16(B|L)E,version=1: writeBOM | acceptBOM | requireBOM | strictBOM
- // (UnicodeBig and UnicodeLittle in Java)
- // - RFC 2781-compliant, but less common interpretation for UTF-16(B|L)E:
- // acceptBOM | strictBOM (e.g. assigned to CheckBOM).
- // This addition would be consistent with supporting ExpectBOM.
-)
-
-// Endianness is a UTF-16 encoding's default endianness.
-type Endianness bool
-
-const (
- // BigEndian is UTF-16BE.
- BigEndian Endianness = false
- // LittleEndian is UTF-16LE.
- LittleEndian Endianness = true
-)
-
-// ErrMissingBOM means that decoding UTF-16 input with ExpectBOM did not find a
-// starting byte order mark.
-var ErrMissingBOM = errors.New("encoding: missing byte order mark")
-
-type utf16Encoding struct {
- config
- mib identifier.MIB
-}
-
-type config struct {
- endianness Endianness
- bomPolicy BOMPolicy
-}
-
-func (u utf16Encoding) NewDecoder() *encoding.Decoder {
- return &encoding.Decoder{Transformer: &utf16Decoder{
- initial: u.config,
- current: u.config,
- }}
-}
-
-func (u utf16Encoding) NewEncoder() *encoding.Encoder {
- return &encoding.Encoder{Transformer: &utf16Encoder{
- endianness: u.endianness,
- initialBOMPolicy: u.bomPolicy,
- currentBOMPolicy: u.bomPolicy,
- }}
-}
-
-func (u utf16Encoding) ID() (mib identifier.MIB, other string) {
- return u.mib, ""
-}
-
-func (u utf16Encoding) String() string {
- e, b := "B", ""
- if u.endianness == LittleEndian {
- e = "L"
- }
- switch u.bomPolicy {
- case ExpectBOM:
- b = "Expect"
- case UseBOM:
- b = "Use"
- case IgnoreBOM:
- b = "Ignore"
- }
- return "UTF-16" + e + "E (" + b + " BOM)"
-}
-
-type utf16Decoder struct {
- initial config
- current config
-}
-
-func (u *utf16Decoder) Reset() {
- u.current = u.initial
-}
-
-func (u *utf16Decoder) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
- if len(src) == 0 {
- if atEOF && u.current.bomPolicy&requireBOM != 0 {
- return 0, 0, ErrMissingBOM
- }
- return 0, 0, nil
- }
- if u.current.bomPolicy&acceptBOM != 0 {
- if len(src) < 2 {
- return 0, 0, transform.ErrShortSrc
- }
- switch {
- case src[0] == 0xfe && src[1] == 0xff:
- u.current.endianness = BigEndian
- nSrc = 2
- case src[0] == 0xff && src[1] == 0xfe:
- u.current.endianness = LittleEndian
- nSrc = 2
- default:
- if u.current.bomPolicy&requireBOM != 0 {
- return 0, 0, ErrMissingBOM
- }
- }
- u.current.bomPolicy = IgnoreBOM
- }
-
- var r rune
- var dSize, sSize int
- for nSrc < len(src) {
- if nSrc+1 < len(src) {
- x := uint16(src[nSrc+0])<<8 | uint16(src[nSrc+1])
- if u.current.endianness == LittleEndian {
- x = x>>8 | x<<8
- }
- r, sSize = rune(x), 2
- if utf16.IsSurrogate(r) {
- if nSrc+3 < len(src) {
- x = uint16(src[nSrc+2])<<8 | uint16(src[nSrc+3])
- if u.current.endianness == LittleEndian {
- x = x>>8 | x<<8
- }
- // Save for next iteration if it is not a high surrogate.
- if isHighSurrogate(rune(x)) {
- r, sSize = utf16.DecodeRune(r, rune(x)), 4
- }
- } else if !atEOF {
- err = transform.ErrShortSrc
- break
- }
- }
- if dSize = utf8.RuneLen(r); dSize < 0 {
- r, dSize = utf8.RuneError, 3
- }
- } else if atEOF {
- // Single trailing byte.
- r, dSize, sSize = utf8.RuneError, 3, 1
- } else {
- err = transform.ErrShortSrc
- break
- }
- if nDst+dSize > len(dst) {
- err = transform.ErrShortDst
- break
- }
- nDst += utf8.EncodeRune(dst[nDst:], r)
- nSrc += sSize
- }
- return nDst, nSrc, err
-}
-
-func isHighSurrogate(r rune) bool {
- return 0xDC00 <= r && r <= 0xDFFF
-}
-
-type utf16Encoder struct {
- endianness Endianness
- initialBOMPolicy BOMPolicy
- currentBOMPolicy BOMPolicy
-}
-
-func (u *utf16Encoder) Reset() {
- u.currentBOMPolicy = u.initialBOMPolicy
-}
-
-func (u *utf16Encoder) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
- if u.currentBOMPolicy&writeBOM != 0 {
- if len(dst) < 2 {
- return 0, 0, transform.ErrShortDst
- }
- dst[0], dst[1] = 0xfe, 0xff
- u.currentBOMPolicy = IgnoreBOM
- nDst = 2
- }
-
- r, size := rune(0), 0
- for nSrc < len(src) {
- 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
- }
- }
- }
-
- if r <= 0xffff {
- if nDst+2 > len(dst) {
- err = transform.ErrShortDst
- break
- }
- dst[nDst+0] = uint8(r >> 8)
- dst[nDst+1] = uint8(r)
- nDst += 2
- } else {
- if nDst+4 > len(dst) {
- err = transform.ErrShortDst
- break
- }
- r1, r2 := utf16.EncodeRune(r)
- dst[nDst+0] = uint8(r1 >> 8)
- dst[nDst+1] = uint8(r1)
- dst[nDst+2] = uint8(r2 >> 8)
- dst[nDst+3] = uint8(r2)
- nDst += 4
- }
- nSrc += size
- }
-
- if u.endianness == LittleEndian {
- for i := 0; i < nDst; i += 2 {
- dst[i], dst[i+1] = dst[i+1], dst[i]
- }
- }
- return nDst, nSrc, err
-}