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-rw-r--r--vendor/golang.org/x/text/encoding/unicode/utf32/utf32.go296
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diff --git a/vendor/golang.org/x/text/encoding/unicode/utf32/utf32.go b/vendor/golang.org/x/text/encoding/unicode/utf32/utf32.go
deleted file mode 100644
index 48b2152..0000000
--- a/vendor/golang.org/x/text/encoding/unicode/utf32/utf32.go
+++ /dev/null
@@ -1,296 +0,0 @@
-// Copyright 2016 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 utf32 provides the UTF-32 Unicode encoding.
-//
-// Please note that support for UTF-32 is discouraged as it is a rare and
-// inefficient encoding, unfit for use as an interchange format. For use
-// on the web, the W3C strongly discourages its use
-// (https://www.w3.org/TR/html5/document-metadata.html#charset)
-// while WHATWG directly prohibits supporting it
-// (https://html.spec.whatwg.org/multipage/syntax.html#character-encodings).
-package utf32 // import "golang.org/x/text/encoding/unicode/utf32"
-
-import (
- "errors"
- "unicode/utf8"
-
- "golang.org/x/text/encoding"
- "golang.org/x/text/encoding/internal/identifier"
- "golang.org/x/text/transform"
-)
-
-// All lists a configuration for each IANA-defined UTF-32 variant.
-var All = []encoding.Encoding{
- UTF32(BigEndian, UseBOM),
- UTF32(BigEndian, IgnoreBOM),
- UTF32(LittleEndian, IgnoreBOM),
-}
-
-// ErrMissingBOM means that decoding UTF-32 input with ExpectBOM did not
-// find a starting byte order mark.
-var ErrMissingBOM = errors.New("encoding: missing byte order mark")
-
-// UTF32 returns a UTF-32 Encoding for the given default endianness and
-// byte order mark (BOM) policy.
-//
-// When decoding from UTF-32 to UTF-8, if the BOMPolicy is IgnoreBOM then
-// neither BOMs U+FEFF nor ill-formed code units 0xFFFE0000 in the input
-// stream will affect the endianness used for decoding. Instead BOMs will
-// be output as their standard UTF-8 encoding "\xef\xbb\xbf" while
-// 0xFFFE0000 code units will be output as "\xef\xbf\xbd", the standard
-// UTF-8 encoding for the Unicode replacement character. If the BOMPolicy
-// is UseBOM or ExpectBOM a starting 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 ill-formed code
-// units 0xFFFE0000 will not affect the endianness used, and will instead
-// be output as their standard UTF-8 (replacement) 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-32, 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-32 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 http://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 UTF32(e Endianness, b BOMPolicy) encoding.Encoding {
- return utf32Encoding{config{e, b}, mibValue[e][b&bomMask]}
-}
-
-// mibValue maps Endianness and BOMPolicy settings to MIB constants for UTF-32.
-// Note that some configurations map to the same MIB identifier.
-var mibValue = map[Endianness][numBOMValues]identifier.MIB{
- BigEndian: [numBOMValues]identifier.MIB{
- IgnoreBOM: identifier.UTF32BE,
- UseBOM: identifier.UTF32,
- },
- LittleEndian: [numBOMValues]identifier.MIB{
- IgnoreBOM: identifier.UTF32LE,
- UseBOM: identifier.UTF32,
- },
- // ExpectBOM is not widely used and has no valid MIB identifier.
-}
-
-// BOMPolicy is a UTF-32 encodings'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
- // Unicode-compliant interpretation for UTF-32BE/LE.
-
- // UseBOM means that the UTF-32 form may start with a byte order mark,
- // which will be used to override the default encoding.
- UseBOM BOMPolicy = writeBOM | acceptBOM
- // Unicode-compliant interpretation for UTF-32.
-
- // ExpectBOM means that the UTF-32 form must start with a byte order mark,
- // which will be used to override the default encoding.
- ExpectBOM BOMPolicy = writeBOM | acceptBOM | requireBOM
- // Consistent with BOMPolicy definition in golang.org/x/text/encoding/unicode
-)
-
-// Endianness is a UTF-32 encoding's default endianness.
-type Endianness bool
-
-const (
- // BigEndian is UTF-32BE.
- BigEndian Endianness = false
- // LittleEndian is UTF-32LE.
- LittleEndian Endianness = true
-)
-
-type config struct {
- endianness Endianness
- bomPolicy BOMPolicy
-}
-
-type utf32Encoding struct {
- config
- mib identifier.MIB
-}
-
-func (u utf32Encoding) NewDecoder() *encoding.Decoder {
- return &encoding.Decoder{Transformer: &utf32Decoder{
- initial: u.config,
- current: u.config,
- }}
-}
-
-func (u utf32Encoding) NewEncoder() *encoding.Encoder {
- return &encoding.Encoder{Transformer: &utf32Encoder{
- endianness: u.endianness,
- initialBOMPolicy: u.bomPolicy,
- currentBOMPolicy: u.bomPolicy,
- }}
-}
-
-func (u utf32Encoding) ID() (mib identifier.MIB, other string) {
- return u.mib, ""
-}
-
-func (u utf32Encoding) 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-32" + e + "E (" + b + " BOM)"
-}
-
-type utf32Decoder struct {
- initial config
- current config
-}
-
-func (u *utf32Decoder) Reset() {
- u.current = u.initial
-}
-
-func (u *utf32Decoder) 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) < 4 {
- return 0, 0, transform.ErrShortSrc
- }
- switch {
- case src[0] == 0x00 && src[1] == 0x00 && src[2] == 0xfe && src[3] == 0xff:
- u.current.endianness = BigEndian
- nSrc = 4
- case src[0] == 0xff && src[1] == 0xfe && src[2] == 0x00 && src[3] == 0x00:
- u.current.endianness = LittleEndian
- nSrc = 4
- 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+3 < len(src) {
- x := uint32(src[nSrc+0])<<24 | uint32(src[nSrc+1])<<16 |
- uint32(src[nSrc+2])<<8 | uint32(src[nSrc+3])
- if u.current.endianness == LittleEndian {
- x = x>>24 | (x >> 8 & 0x0000FF00) | (x << 8 & 0x00FF0000) | x<<24
- }
- r, sSize = rune(x), 4
- if dSize = utf8.RuneLen(r); dSize < 0 {
- r, dSize = utf8.RuneError, 3
- }
- } else if atEOF {
- // 1..3 trailing bytes.
- r, dSize, sSize = utf8.RuneError, 3, len(src)-nSrc
- } 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
-}
-
-type utf32Encoder struct {
- endianness Endianness
- initialBOMPolicy BOMPolicy
- currentBOMPolicy BOMPolicy
-}
-
-func (u *utf32Encoder) Reset() {
- u.currentBOMPolicy = u.initialBOMPolicy
-}
-
-func (u *utf32Encoder) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
- if u.currentBOMPolicy&writeBOM != 0 {
- if len(dst) < 4 {
- return 0, 0, transform.ErrShortDst
- }
- dst[0], dst[1], dst[2], dst[3] = 0x00, 0x00, 0xfe, 0xff
- u.currentBOMPolicy = IgnoreBOM
- nDst = 4
- }
-
- 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 nDst+4 > len(dst) {
- err = transform.ErrShortDst
- break
- }
-
- dst[nDst+0] = uint8(r >> 24)
- dst[nDst+1] = uint8(r >> 16)
- dst[nDst+2] = uint8(r >> 8)
- dst[nDst+3] = uint8(r)
- nDst += 4
- nSrc += size
- }
-
- if u.endianness == LittleEndian {
- for i := 0; i < nDst; i += 4 {
- dst[i], dst[i+1], dst[i+2], dst[i+3] = dst[i+3], dst[i+2], dst[i+1], dst[i]
- }
- }
- return nDst, nSrc, err
-}