gitroast/modules/mahonia/convert_string.go

136 lines
2.4 KiB
Go

package mahonia
import (
"unicode/utf8"
)
// ConvertString converts a string from UTF-8 to e's encoding.
func (e Encoder) ConvertString(s string) string {
dest := make([]byte, len(s)+10)
destPos := 0
for _, rune := range s {
retry:
size, status := e(dest[destPos:], rune)
if status == NO_ROOM {
newDest := make([]byte, len(dest)*2)
copy(newDest, dest)
dest = newDest
goto retry
}
if status == STATE_ONLY {
destPos += size
goto retry
}
destPos += size
}
return string(dest[:destPos])
}
// ConvertString converts a string from d's encoding to UTF-8.
func (d Decoder) ConvertString(s string) string {
bytes := []byte(s)
runes := make([]rune, len(s))
destPos := 0
for len(bytes) > 0 {
c, size, status := d(bytes)
if status == STATE_ONLY {
bytes = bytes[size:]
continue
}
if status == NO_ROOM {
c = 0xfffd
size = len(bytes)
status = INVALID_CHAR
}
bytes = bytes[size:]
runes[destPos] = c
destPos++
}
return string(runes[:destPos])
}
// ConvertStringOK converts a string from UTF-8 to e's encoding. It also
// returns a boolean indicating whether every character was converted
// successfully.
func (e Encoder) ConvertStringOK(s string) (result string, ok bool) {
dest := make([]byte, len(s)+10)
destPos := 0
ok = true
for i, r := range s {
// The following test is copied from utf8.ValidString.
if r == utf8.RuneError && ok {
_, size := utf8.DecodeRuneInString(s[i:])
if size == 1 {
ok = false
}
}
retry:
size, status := e(dest[destPos:], r)
switch status {
case NO_ROOM:
newDest := make([]byte, len(dest)*2)
copy(newDest, dest)
dest = newDest
goto retry
case STATE_ONLY:
destPos += size
goto retry
case INVALID_CHAR:
ok = false
}
destPos += size
}
return string(dest[:destPos]), ok
}
// ConvertStringOK converts a string from d's encoding to UTF-8.
// It also returns a boolean indicating whether every character was converted
// successfully.
func (d Decoder) ConvertStringOK(s string) (result string, ok bool) {
bytes := []byte(s)
runes := make([]rune, len(s))
destPos := 0
ok = true
for len(bytes) > 0 {
c, size, status := d(bytes)
switch status {
case STATE_ONLY:
bytes = bytes[size:]
continue
case NO_ROOM:
c = 0xfffd
size = len(bytes)
ok = false
case INVALID_CHAR:
ok = false
}
bytes = bytes[size:]
runes[destPos] = c
destPos++
}
return string(runes[:destPos]), ok
}