mox/vendor/golang.org/x/text/encoding/internal/internal.go
Mechiel Lukkien 01adad62b2
implement decoding charsets (other than ascii and utf-8) while reading textual message parts, and improve search
message.Part now has a ReaderUTF8OrBinary() along with the existing Reader().
the new function returns a reader of decoded content. we now use it in a few
places, including search. we only support the charsets in
golang.org/x/text/encoding/ianaindex.

search has also been changed to not read the entire message in memory. instead,
we make one 8k buffer for reading and search in that, and we keep the buffer
around for all messages. saves quite some allocations when searching large
mailboxes.
2023-07-28 22:15:23 +02:00

75 lines
2.1 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.
// Package internal contains code that is shared among encoding implementations.
package internal
import (
"golang.org/x/text/encoding"
"golang.org/x/text/encoding/internal/identifier"
"golang.org/x/text/transform"
)
// Encoding is an implementation of the Encoding interface that adds the String
// and ID methods to an existing encoding.
type Encoding struct {
encoding.Encoding
Name string
MIB identifier.MIB
}
// _ verifies that Encoding implements identifier.Interface.
var _ identifier.Interface = (*Encoding)(nil)
func (e *Encoding) String() string {
return e.Name
}
func (e *Encoding) ID() (mib identifier.MIB, other string) {
return e.MIB, ""
}
// SimpleEncoding is an Encoding that combines two Transformers.
type SimpleEncoding struct {
Decoder transform.Transformer
Encoder transform.Transformer
}
func (e *SimpleEncoding) NewDecoder() *encoding.Decoder {
return &encoding.Decoder{Transformer: e.Decoder}
}
func (e *SimpleEncoding) NewEncoder() *encoding.Encoder {
return &encoding.Encoder{Transformer: e.Encoder}
}
// FuncEncoding is an Encoding that combines two functions returning a new
// Transformer.
type FuncEncoding struct {
Decoder func() transform.Transformer
Encoder func() transform.Transformer
}
func (e FuncEncoding) NewDecoder() *encoding.Decoder {
return &encoding.Decoder{Transformer: e.Decoder()}
}
func (e FuncEncoding) NewEncoder() *encoding.Encoder {
return &encoding.Encoder{Transformer: e.Encoder()}
}
// A RepertoireError indicates a rune is not in the repertoire of a destination
// encoding. It is associated with an encoding-specific suggested replacement
// byte.
type RepertoireError byte
// Error implements the error interface.
func (r RepertoireError) Error() string {
return "encoding: rune not supported by encoding."
}
// Replacement returns the replacement string associated with this error.
func (r RepertoireError) Replacement() byte { return byte(r) }
var ErrASCIIReplacement = RepertoireError(encoding.ASCIISub)