mirror of
https://github.com/Luzifer/duplicity-backup.git
synced 2024-12-21 11:01:20 +00:00
86 lines
2.6 KiB
Go
86 lines
2.6 KiB
Go
// Copyright 2015 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.
|
|
|
|
//go:generate go run gen.go
|
|
|
|
// Package htmlindex maps character set encoding names to Encodings as
|
|
// recommended by the W3C for use in HTML 5. See http://www.w3.org/TR/encoding.
|
|
package htmlindex
|
|
|
|
// TODO: perhaps have a "bare" version of the index (used by this package) that
|
|
// is not pre-loaded with all encodings. Global variables in encodings prevent
|
|
// the linker from being able to purge unneeded tables. This means that
|
|
// referencing all encodings, as this package does for the default index, links
|
|
// in all encodings unconditionally.
|
|
//
|
|
// This issue can be solved by either solving the linking issue (see
|
|
// https://github.com/golang/go/issues/6330) or refactoring the encoding tables
|
|
// (e.g. moving the tables to internal packages that do not use global
|
|
// variables).
|
|
|
|
// TODO: allow canonicalizing names
|
|
|
|
import (
|
|
"errors"
|
|
"strings"
|
|
"sync"
|
|
|
|
"golang.org/x/text/encoding"
|
|
"golang.org/x/text/encoding/internal/identifier"
|
|
"golang.org/x/text/language"
|
|
)
|
|
|
|
var (
|
|
errInvalidName = errors.New("htmlindex: invalid encoding name")
|
|
errUnknown = errors.New("htmlindex: unknown Encoding")
|
|
errUnsupported = errors.New("htmlindex: this encoding is not supported")
|
|
)
|
|
|
|
var (
|
|
matcherOnce sync.Once
|
|
matcher language.Matcher
|
|
)
|
|
|
|
// LanguageDefault returns the canonical name of the default encoding for a
|
|
// given language.
|
|
func LanguageDefault(tag language.Tag) string {
|
|
matcherOnce.Do(func() {
|
|
tags := []language.Tag{}
|
|
for _, t := range strings.Split(locales, " ") {
|
|
tags = append(tags, language.MustParse(t))
|
|
}
|
|
matcher = language.NewMatcher(tags, language.PreferSameScript(true))
|
|
})
|
|
_, i, _ := matcher.Match(tag)
|
|
return canonical[localeMap[i]] // Default is Windows-1252.
|
|
}
|
|
|
|
// Get returns an Encoding for one of the names listed in
|
|
// http://www.w3.org/TR/encoding using the Default Index. Matching is case-
|
|
// insensitive.
|
|
func Get(name string) (encoding.Encoding, error) {
|
|
x, ok := nameMap[strings.ToLower(strings.TrimSpace(name))]
|
|
if !ok {
|
|
return nil, errInvalidName
|
|
}
|
|
return encodings[x], nil
|
|
}
|
|
|
|
// Name reports the canonical name of the given Encoding. It will return
|
|
// an error if e is not associated with a supported encoding scheme.
|
|
func Name(e encoding.Encoding) (string, error) {
|
|
id, ok := e.(identifier.Interface)
|
|
if !ok {
|
|
return "", errUnknown
|
|
}
|
|
mib, _ := id.ID()
|
|
if mib == 0 {
|
|
return "", errUnknown
|
|
}
|
|
v, ok := mibMap[mib]
|
|
if !ok {
|
|
return "", errUnsupported
|
|
}
|
|
return canonical[v], nil
|
|
}
|