rclone/lib/encoder/encoder.go
Josh Soref d0888edc0a Spelling fixes
Fix spelling of: above, already, anonymous, associated,
authentication, bandwidth, because, between, blocks, calculate,
candidates, cautious, changelog, cleaner, clipboard, command,
completely, concurrently, considered, constructs, corrupt, current,
daemon, dependencies, deprecated, directory, dispatcher, download,
eligible, ellipsis, encrypter, endpoint, entrieslist, essentially,
existing writers, existing, expires, filesystem, flushing, frequently,
hierarchy, however, implementation, implements, inaccurate,
individually, insensitive, longer, maximum, metadata, modified,
multipart, namedirfirst, nextcloud, obscured, opened, optional,
owncloud, pacific, passphrase, password, permanently, persimmon,
positive, potato, protocol, quota, receiving, recommends, referring,
requires, revisited, satisfied, satisfies, satisfy, semver,
serialized, session, storage, strategies, stringlist, successful,
supported, surprise, temporarily, temporary, transactions, unneeded,
update, uploads, wrapped

Signed-off-by: Josh Soref <jsoref@users.noreply.github.com>
2020-10-14 15:21:31 +01:00

1160 lines
27 KiB
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This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
Translate file names for usage on restrictive storage systems
The restricted set of characters are mapped to a unicode equivalent version
(most to their FULLWIDTH variant) to increase compatibility with other
storage systems.
See: http://unicode-search.net/unicode-namesearch.pl?term=FULLWIDTH
Encoders will also quote reserved characters to differentiate between
the raw and encoded forms.
*/
package encoder
import (
"bytes"
"fmt"
"io"
"sort"
"strconv"
"strings"
"unicode/utf8"
)
const (
// adding this to any printable ASCII character turns it into the
// FULLWIDTH variant
fullOffset = 0xFEE0
// the first rune of the SYMBOL FOR block for control characters
symbolOffset = '␀' // SYMBOL FOR NULL
// QuoteRune is the rune used for quoting reserved characters
QuoteRune = '' // SINGLE HIGH-REVERSED-9 QUOTATION MARK
)
// NB keep the tests in fstests/fstests/fstests.go FsEncoding up to date with this
// NB keep the aliases up to date below also
// Possible flags for the MultiEncoder
const (
EncodeZero MultiEncoder = 0 // NUL(0x00)
EncodeSlash MultiEncoder = 1 << iota // /
EncodeLtGt // <>
EncodeDoubleQuote // "
EncodeSingleQuote // '
EncodeBackQuote // `
EncodeDollar // $
EncodeColon // :
EncodeQuestion // ?
EncodeAsterisk // *
EncodePipe // |
EncodeHash // #
EncodePercent // %
EncodeBackSlash // \
EncodeCrLf // CR(0x0D), LF(0x0A)
EncodeDel // DEL(0x7F)
EncodeCtl // CTRL(0x01-0x1F)
EncodeLeftSpace // Leading SPACE
EncodeLeftPeriod // Leading .
EncodeLeftTilde // Leading ~
EncodeLeftCrLfHtVt // Leading CR LF HT VT
EncodeRightSpace // Trailing SPACE
EncodeRightPeriod // Trailing .
EncodeRightCrLfHtVt // Trailing CR LF HT VT
EncodeInvalidUtf8 // Invalid UTF-8 bytes
EncodeDot // . and .. names
// Synthetic
EncodeWin = EncodeColon | EncodeQuestion | EncodeDoubleQuote | EncodeAsterisk | EncodeLtGt | EncodePipe // :?"*<>|
EncodeHashPercent = EncodeHash | EncodePercent // #%
)
// Has returns true if flag is contained in mask
func (mask MultiEncoder) Has(flag MultiEncoder) bool {
return mask&flag != 0
}
// Encoder can transform names to and from the original and translated version.
type Encoder interface {
// Encode takes a raw name and substitutes any reserved characters and
// patterns in it
Encode(string) string
// Decode takes a name and undoes any substitutions made by Encode
Decode(string) string
// FromStandardPath takes a / separated path in Standard encoding
// and converts it to a / separated path in this encoding.
FromStandardPath(string) string
// FromStandardName takes name in Standard encoding and converts
// it in this encoding.
FromStandardName(string) string
// ToStandardPath takes a / separated path in this encoding
// and converts it to a / separated path in Standard encoding.
ToStandardPath(string) string
// ToStandardName takes name in this encoding and converts
// it in Standard encoding.
ToStandardName(string) string
}
// MultiEncoder is a configurable Encoder. The Encode* constants in this
// package can be combined using bitwise or (|) to enable handling of multiple
// character classes
type MultiEncoder uint
// Aliases maps encodings to names and vice versa
var (
encodingToName = map[MultiEncoder]string{}
nameToEncoding = map[string]MultiEncoder{}
)
// alias adds an alias for MultiEncoder.String() and MultiEncoder.Set()
func alias(name string, mask MultiEncoder) {
nameToEncoding[name] = mask
// don't overwrite existing reverse translations
if _, ok := encodingToName[mask]; !ok {
encodingToName[mask] = name
}
}
func init() {
alias("None", EncodeZero)
alias("Slash", EncodeSlash)
alias("LtGt", EncodeLtGt)
alias("DoubleQuote", EncodeDoubleQuote)
alias("SingleQuote", EncodeSingleQuote)
alias("BackQuote", EncodeBackQuote)
alias("Dollar", EncodeDollar)
alias("Colon", EncodeColon)
alias("Question", EncodeQuestion)
alias("Asterisk", EncodeAsterisk)
alias("Pipe", EncodePipe)
alias("Hash", EncodeHash)
alias("Percent", EncodePercent)
alias("BackSlash", EncodeBackSlash)
alias("CrLf", EncodeCrLf)
alias("Del", EncodeDel)
alias("Ctl", EncodeCtl)
alias("LeftSpace", EncodeLeftSpace)
alias("LeftPeriod", EncodeLeftPeriod)
alias("LeftTilde", EncodeLeftTilde)
alias("LeftCrLfHtVt", EncodeLeftCrLfHtVt)
alias("RightSpace", EncodeRightSpace)
alias("RightPeriod", EncodeRightPeriod)
alias("RightCrLfHtVt", EncodeRightCrLfHtVt)
alias("InvalidUtf8", EncodeInvalidUtf8)
alias("Dot", EncodeDot)
}
// validStrings returns all the valid MultiEncoder strings
func validStrings() string {
var out []string
for k := range nameToEncoding {
out = append(out, k)
}
sort.Strings(out)
return strings.Join(out, ", ")
}
// String converts the MultiEncoder into text
func (mask MultiEncoder) String() string {
// See if there is an exact translation - if so return that
if name, ok := encodingToName[mask]; ok {
return name
}
var out []string
// Otherwise decompose bit by bit
for bit := MultiEncoder(1); bit != 0; bit *= 2 {
if (mask & bit) != 0 {
if name, ok := encodingToName[bit]; ok {
out = append(out, name)
} else {
out = append(out, fmt.Sprintf("0x%X", uint(bit)))
}
}
}
return strings.Join(out, ",")
}
// Set converts a string into a MultiEncoder
func (mask *MultiEncoder) Set(in string) error {
var out MultiEncoder
parts := strings.Split(in, ",")
for _, part := range parts {
part = strings.TrimSpace(part)
if bits, ok := nameToEncoding[part]; ok {
out |= bits
} else {
i, err := strconv.ParseInt(part, 0, 64)
if err != nil {
return fmt.Errorf("bad encoding %q: possible values are: %s", part, validStrings())
}
out |= MultiEncoder(i)
}
}
*mask = out
return nil
}
// Type returns a textual type of the MultiEncoder to satisfy the pflag.Value interface
func (mask MultiEncoder) Type() string {
return "Encoding"
}
// Scan implements the fmt.Scanner interface
func (mask *MultiEncoder) Scan(s fmt.ScanState, ch rune) error {
token, err := s.Token(true, nil)
if err != nil {
return err
}
return mask.Set(string(token))
}
// Encode takes a raw name and substitutes any reserved characters and
// patterns in it
func (mask MultiEncoder) Encode(in string) string {
if in == "" {
return ""
}
if mask.Has(EncodeDot) {
switch in {
case ".":
return ""
case "..":
return ""
case "":
return string(QuoteRune) + ""
case "":
return string(QuoteRune) + "" + string(QuoteRune) + ""
}
}
// handle prefix only replacements
prefix := ""
if mask.Has(EncodeLeftSpace) { // Leading SPACE
if in[0] == ' ' {
prefix, in = "␠", in[1:] // SYMBOL FOR SPACE
} else if r, l := utf8.DecodeRuneInString(in); r == '␠' { // SYMBOL FOR SPACE
prefix, in = string(QuoteRune)+"␠", in[l:] // SYMBOL FOR SPACE
}
}
if mask.Has(EncodeLeftPeriod) && prefix == "" { // Leading PERIOD
if in[0] == '.' {
prefix, in = "", in[1:] // FULLWIDTH FULL STOP
} else if r, l := utf8.DecodeRuneInString(in); r == '' { // FULLWIDTH FULL STOP
prefix, in = string(QuoteRune)+"", in[l:] // FULLWIDTH FULL STOP
}
}
if mask.Has(EncodeLeftTilde) && prefix == "" { // Leading ~
if in[0] == '~' {
prefix, in = string('~'+fullOffset), in[1:] // FULLWIDTH TILDE
} else if r, l := utf8.DecodeRuneInString(in); r == '~'+fullOffset {
prefix, in = string(QuoteRune)+string('~'+fullOffset), in[l:] // FULLWIDTH TILDE
}
}
if mask.Has(EncodeLeftCrLfHtVt) && prefix == "" { // Leading CR LF HT VT
switch c := in[0]; c {
case '\t', '\n', '\v', '\r':
prefix, in = string('␀'+rune(c)), in[1:] // SYMBOL FOR NULL
default:
switch r, l := utf8.DecodeRuneInString(in); r {
case '␀' + '\t', '␀' + '\n', '␀' + '\v', '␀' + '\r':
prefix, in = string(QuoteRune)+string(r), in[l:]
}
}
}
// handle suffix only replacements
suffix := ""
if in != "" {
if mask.Has(EncodeRightSpace) { // Trailing SPACE
if in[len(in)-1] == ' ' {
suffix, in = "␠", in[:len(in)-1] // SYMBOL FOR SPACE
} else if r, l := utf8.DecodeLastRuneInString(in); r == '␠' {
suffix, in = string(QuoteRune)+"␠", in[:len(in)-l] // SYMBOL FOR SPACE
}
}
if mask.Has(EncodeRightPeriod) && suffix == "" { // Trailing .
if in[len(in)-1] == '.' {
suffix, in = "", in[:len(in)-1] // FULLWIDTH FULL STOP
} else if r, l := utf8.DecodeLastRuneInString(in); r == '' {
suffix, in = string(QuoteRune)+"", in[:len(in)-l] // FULLWIDTH FULL STOP
}
}
if mask.Has(EncodeRightCrLfHtVt) && suffix == "" { // Trailing .
switch c := in[len(in)-1]; c {
case '\t', '\n', '\v', '\r':
suffix, in = string('␀'+rune(c)), in[:len(in)-1] // FULLWIDTH FULL STOP
default:
switch r, l := utf8.DecodeLastRuneInString(in); r {
case '␀' + '\t', '␀' + '\n', '␀' + '\v', '␀' + '\r':
suffix, in = string(QuoteRune)+string(r), in[:len(in)-l]
}
}
}
}
index := 0
if prefix == "" && suffix == "" {
// find the first rune which (most likely) needs to be replaced
index = strings.IndexFunc(in, func(r rune) bool {
switch r {
case 0, '␀', QuoteRune, utf8.RuneError:
return true
}
if mask.Has(EncodeAsterisk) { // *
switch r {
case '*',
'':
return true
}
}
if mask.Has(EncodeLtGt) { // <>
switch r {
case '<', '>',
'', '':
return true
}
}
if mask.Has(EncodeQuestion) { // ?
switch r {
case '?',
'':
return true
}
}
if mask.Has(EncodeColon) { // :
switch r {
case ':',
'':
return true
}
}
if mask.Has(EncodePipe) { // |
switch r {
case '|',
'':
return true
}
}
if mask.Has(EncodeDoubleQuote) { // "
switch r {
case '"',
'':
return true
}
}
if mask.Has(EncodeSingleQuote) { // '
switch r {
case '\'',
'':
return true
}
}
if mask.Has(EncodeBackQuote) { // `
switch r {
case '`',
'':
return true
}
}
if mask.Has(EncodeDollar) { // $
switch r {
case '$',
'':
return true
}
}
if mask.Has(EncodeSlash) { // /
switch r {
case '/',
'':
return true
}
}
if mask.Has(EncodeBackSlash) { // \
switch r {
case '\\',
'':
return true
}
}
if mask.Has(EncodeCrLf) { // CR LF
switch r {
case rune(0x0D), rune(0x0A),
'␍', '␊':
return true
}
}
if mask.Has(EncodeHash) { // #
switch r {
case '#',
'':
return true
}
}
if mask.Has(EncodePercent) { // %
switch r {
case '%',
'':
return true
}
}
if mask.Has(EncodeDel) { // DEL(0x7F)
switch r {
case rune(0x7F), '␡':
return true
}
}
if mask.Has(EncodeCtl) { // CTRL(0x01-0x1F)
if r >= 1 && r <= 0x1F {
return true
} else if r > symbolOffset && r <= symbolOffset+0x1F {
return true
}
}
return false
})
}
// nothing to replace, return input
if index == -1 {
return in
}
var out bytes.Buffer
out.Grow(len(in) + len(prefix) + len(suffix))
out.WriteString(prefix)
// copy the clean part of the input and skip it
out.WriteString(in[:index])
in = in[index:]
for i, r := range in {
switch r {
case 0:
out.WriteRune(symbolOffset)
continue
case '␀', QuoteRune:
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
case utf8.RuneError:
if mask.Has(EncodeInvalidUtf8) {
// only encode invalid sequences and not utf8.RuneError
if i+3 > len(in) || in[i:i+3] != string(utf8.RuneError) {
_, l := utf8.DecodeRuneInString(in[i:])
appendQuotedBytes(&out, in[i:i+l])
continue
}
} else {
// append the real bytes instead of utf8.RuneError
_, l := utf8.DecodeRuneInString(in[i:])
out.WriteString(in[i : i+l])
continue
}
}
if mask.Has(EncodeAsterisk) { // *
switch r {
case '*':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeLtGt) { // <>
switch r {
case '<', '>':
out.WriteRune(r + fullOffset)
continue
case '', '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeQuestion) { // ?
switch r {
case '?':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeColon) { // :
switch r {
case ':':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodePipe) { // |
switch r {
case '|':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeDoubleQuote) { // "
switch r {
case '"':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeSingleQuote) { // '
switch r {
case '\'':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeBackQuote) { // `
switch r {
case '`':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeDollar) { // $
switch r {
case '$':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeSlash) { // /
switch r {
case '/':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeBackSlash) { // \
switch r {
case '\\':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeCrLf) { // CR LF
switch r {
case rune(0x0D), rune(0x0A):
out.WriteRune(r + symbolOffset)
continue
case '␍', '␊':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeHash) { // #
switch r {
case '#':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodePercent) { // %
switch r {
case '%':
out.WriteRune(r + fullOffset)
continue
case '':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeDel) { // DEL(0x7F)
switch r {
case rune(0x7F):
out.WriteRune('␡') // SYMBOL FOR DELETE
continue
case '␡':
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
if mask.Has(EncodeCtl) { // CTRL(0x01-0x1F)
if r >= 1 && r <= 0x1F {
out.WriteRune('␀' + r) // SYMBOL FOR NULL
continue
} else if r > symbolOffset && r <= symbolOffset+0x1F {
out.WriteRune(QuoteRune)
out.WriteRune(r)
continue
}
}
out.WriteRune(r)
}
out.WriteString(suffix)
return out.String()
}
// Decode takes a name and undoes any substitutions made by Encode
func (mask MultiEncoder) Decode(in string) string {
if mask.Has(EncodeDot) {
switch in {
case "":
return "."
case "":
return ".."
case string(QuoteRune) + "":
return ""
case string(QuoteRune) + "" + string(QuoteRune) + "":
return ""
}
}
// handle prefix only replacements
prefix := ""
if r, l1 := utf8.DecodeRuneInString(in); mask.Has(EncodeLeftSpace) && r == '␠' { // SYMBOL FOR SPACE
prefix, in = " ", in[l1:]
} else if mask.Has(EncodeLeftPeriod) && r == '' { // FULLWIDTH FULL STOP
prefix, in = ".", in[l1:]
} else if mask.Has(EncodeLeftTilde) && r == '' { // FULLWIDTH TILDE
prefix, in = "~", in[l1:]
} else if mask.Has(EncodeLeftCrLfHtVt) && (r == '␀'+'\t' || r == '␀'+'\n' || r == '␀'+'\v' || r == '␀'+'\r') {
prefix, in = string(r-'␀'), in[l1:]
} else if r == QuoteRune {
if r, l2 := utf8.DecodeRuneInString(in[l1:]); mask.Has(EncodeLeftSpace) && r == '␠' { // SYMBOL FOR SPACE
prefix, in = "␠", in[l1+l2:]
} else if mask.Has(EncodeLeftPeriod) && r == '' { // FULLWIDTH FULL STOP
prefix, in = "", in[l1+l2:]
} else if mask.Has(EncodeLeftTilde) && r == '' { // FULLWIDTH TILDE
prefix, in = "", in[l1+l2:]
} else if mask.Has(EncodeLeftCrLfHtVt) && (r == '␀'+'\t' || r == '␀'+'\n' || r == '␀'+'\v' || r == '␀'+'\r') {
prefix, in = string(r), in[l1+l2:]
}
}
// handle suffix only replacements
suffix := ""
if r, l := utf8.DecodeLastRuneInString(in); mask.Has(EncodeRightSpace) && r == '␠' { // SYMBOL FOR SPACE
in = in[:len(in)-l]
if q, l2 := utf8.DecodeLastRuneInString(in); q == QuoteRune {
suffix, in = "␠", in[:len(in)-l2]
} else {
suffix = " "
}
} else if mask.Has(EncodeRightPeriod) && r == '' { // FULLWIDTH FULL STOP
in = in[:len(in)-l]
if q, l2 := utf8.DecodeLastRuneInString(in); q == QuoteRune {
suffix, in = "", in[:len(in)-l2]
} else {
suffix = "."
}
} else if mask.Has(EncodeRightCrLfHtVt) && (r == '␀'+'\t' || r == '␀'+'\n' || r == '␀'+'\v' || r == '␀'+'\r') {
in = in[:len(in)-l]
if q, l2 := utf8.DecodeLastRuneInString(in); q == QuoteRune {
suffix, in = string(r), in[:len(in)-l2]
} else {
suffix = string(r - '␀')
}
}
index := 0
if prefix == "" && suffix == "" {
// find the first rune which (most likely) needs to be replaced
index = strings.IndexFunc(in, func(r rune) bool {
switch r {
case '␀', QuoteRune:
return true
}
if mask.Has(EncodeAsterisk) { // *
switch r {
case '':
return true
}
}
if mask.Has(EncodeLtGt) { // <>
switch r {
case '', '':
return true
}
}
if mask.Has(EncodeQuestion) { // ?
switch r {
case '':
return true
}
}
if mask.Has(EncodeColon) { // :
switch r {
case '':
return true
}
}
if mask.Has(EncodePipe) { // |
switch r {
case '':
return true
}
}
if mask.Has(EncodeDoubleQuote) { // "
switch r {
case '':
return true
}
}
if mask.Has(EncodeSingleQuote) { // '
switch r {
case '':
return true
}
}
if mask.Has(EncodeBackQuote) { // `
switch r {
case '':
return true
}
}
if mask.Has(EncodeDollar) { // $
switch r {
case '':
return true
}
}
if mask.Has(EncodeSlash) { // /
switch r {
case '':
return true
}
}
if mask.Has(EncodeBackSlash) { // \
switch r {
case '':
return true
}
}
if mask.Has(EncodeCrLf) { // CR LF
switch r {
case '␍', '␊':
return true
}
}
if mask.Has(EncodeHash) { // #
switch r {
case '':
return true
}
}
if mask.Has(EncodePercent) { // %
switch r {
case '':
return true
}
}
if mask.Has(EncodeDel) { // DEL(0x7F)
switch r {
case '␡':
return true
}
}
if mask.Has(EncodeCtl) { // CTRL(0x01-0x1F)
if r > symbolOffset && r <= symbolOffset+0x1F {
return true
}
}
return false
})
}
// nothing to replace, return input
if index == -1 {
return in
}
var out bytes.Buffer
out.Grow(len(in))
out.WriteString(prefix)
// copy the clean part of the input and skip it
out.WriteString(in[:index])
in = in[index:]
var unquote, unquoteNext, skipNext bool
for i, r := range in {
if skipNext {
skipNext = false
continue
}
unquote, unquoteNext = unquoteNext, false
switch r {
case '␀': // SYMBOL FOR NULL
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(0)
}
continue
case QuoteRune:
if unquote {
out.WriteRune(r)
} else {
unquoteNext = true
}
continue
}
if mask.Has(EncodeAsterisk) { // *
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeLtGt) { // <>
switch r {
case '', '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeQuestion) { // ?
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeColon) { // :
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodePipe) { // |
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeDoubleQuote) { // "
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeSingleQuote) { // '
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeBackQuote) { // `
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeDollar) { // $
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeSlash) { // /
switch r {
case '': // FULLWIDTH SOLIDUS
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeBackSlash) { // \
switch r {
case '': // FULLWIDTH REVERSE SOLIDUS
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeCrLf) { // CR LF
switch r {
case '␍', '␊':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - symbolOffset)
}
continue
}
}
if mask.Has(EncodeHash) { // %
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodePercent) { // %
switch r {
case '':
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - fullOffset)
}
continue
}
}
if mask.Has(EncodeDel) { // DEL(0x7F)
switch r {
case '␡': // SYMBOL FOR DELETE
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(0x7F)
}
continue
}
}
if mask.Has(EncodeCtl) { // CTRL(0x01-0x1F)
if r > symbolOffset && r <= symbolOffset+0x1F {
if unquote {
out.WriteRune(r)
} else {
out.WriteRune(r - symbolOffset)
}
continue
}
}
if unquote {
if mask.Has(EncodeInvalidUtf8) {
skipNext = appendUnquotedByte(&out, in[i:])
if skipNext {
continue
}
}
out.WriteRune(QuoteRune)
}
switch r {
case utf8.RuneError:
// append the real bytes instead of utf8.RuneError
_, l := utf8.DecodeRuneInString(in[i:])
out.WriteString(in[i : i+l])
continue
}
out.WriteRune(r)
}
if unquoteNext {
out.WriteRune(QuoteRune)
}
out.WriteString(suffix)
return out.String()
}
// FromStandardPath takes a / separated path in Standard encoding
// and converts it to a / separated path in this encoding.
func (mask MultiEncoder) FromStandardPath(s string) string {
return FromStandardPath(mask, s)
}
// FromStandardName takes name in Standard encoding and converts
// it in this encoding.
func (mask MultiEncoder) FromStandardName(s string) string {
return FromStandardName(mask, s)
}
// ToStandardPath takes a / separated path in this encoding
// and converts it to a / separated path in Standard encoding.
func (mask MultiEncoder) ToStandardPath(s string) string {
return ToStandardPath(mask, s)
}
// ToStandardName takes name in this encoding and converts
// it in Standard encoding.
func (mask MultiEncoder) ToStandardName(s string) string {
return ToStandardName(mask, s)
}
func appendQuotedBytes(w io.Writer, s string) {
for _, b := range []byte(s) {
_, _ = fmt.Fprintf(w, string(QuoteRune)+"%02X", b)
}
}
func appendUnquotedByte(w io.Writer, s string) bool {
if len(s) < 2 {
return false
}
u, err := strconv.ParseUint(s[:2], 16, 8)
if err != nil {
return false
}
n, _ := w.Write([]byte{byte(u)})
return n == 1
}
type identity struct{}
func (identity) Encode(in string) string { return in }
func (identity) Decode(in string) string { return in }
func (i identity) FromStandardPath(s string) string {
return FromStandardPath(i, s)
}
func (i identity) FromStandardName(s string) string {
return FromStandardName(i, s)
}
func (i identity) ToStandardPath(s string) string {
return ToStandardPath(i, s)
}
func (i identity) ToStandardName(s string) string {
return ToStandardName(i, s)
}
// Identity returns an Encoder that always returns the input value
func Identity() Encoder {
return identity{}
}
// FromStandardPath takes a / separated path in Standard encoding
// and converts it to a / separated path in the given encoding.
func FromStandardPath(e Encoder, s string) string {
if e == Standard {
return s
}
parts := strings.Split(s, "/")
encoded := make([]string, len(parts))
changed := false
for i, p := range parts {
enc := FromStandardName(e, p)
changed = changed || enc != p
encoded[i] = enc
}
if !changed {
return s
}
return strings.Join(encoded, "/")
}
// FromStandardName takes name in Standard encoding and converts
// it in the given encoding.
func FromStandardName(e Encoder, s string) string {
if e == Standard {
return s
}
return e.Encode(Standard.Decode(s))
}
// ToStandardPath takes a / separated path in the given encoding
// and converts it to a / separated path in Standard encoding.
func ToStandardPath(e Encoder, s string) string {
if e == Standard {
return s
}
parts := strings.Split(s, "/")
encoded := make([]string, len(parts))
changed := false
for i, p := range parts {
dec := ToStandardName(e, p)
changed = changed || dec != p
encoded[i] = dec
}
if !changed {
return s
}
return strings.Join(encoded, "/")
}
// ToStandardName takes name in the given encoding and converts
// it in Standard encoding.
func ToStandardName(e Encoder, s string) string {
if e == Standard {
return s
}
return Standard.Encode(e.Decode(s))
}