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Diffstat (limited to 'vendor/golang.org/x/text/encoding/htmlindex/htmlindex.go')
-rw-r--r--vendor/golang.org/x/text/encoding/htmlindex/htmlindex.go86
1 files changed, 86 insertions, 0 deletions
diff --git a/vendor/golang.org/x/text/encoding/htmlindex/htmlindex.go b/vendor/golang.org/x/text/encoding/htmlindex/htmlindex.go
new file mode 100644
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+++ b/vendor/golang.org/x/text/encoding/htmlindex/htmlindex.go
@@ -0,0 +1,86 @@
+// 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
+}