/* ================================================================================== Copyright (c) 2019 AT&T Intellectual Property. Copyright (c) 2019 Nokia Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. ================================================================================== */ package conv type Bcd struct { ConvTbl string } func NewBcd(convTbl string) *Bcd { b := &Bcd{} b.ConvTbl = convTbl return b } func (bcd *Bcd) index(c byte) int { for cpos, cchar := range bcd.ConvTbl { if cchar == rune(c) { return cpos } } return -1 } func (bcd *Bcd) byte(i int) byte { if i < 0 && i > 15 { return '?' } return bcd.ConvTbl[i] } func (bcd *Bcd) Encode(str string) []byte { buf := make([]byte, len(str)/2+len(str)%2) for i := 0; i < len(str); i++ { var schar int = bcd.index(str[i]) if schar < 0 { return nil } if i%2 > 0 { buf[i/2] &= 0x0f buf[i/2] |= (uint8)(schar) << 4 } else { buf[i/2] = 0xf0 | ((uint8)(schar) & 0x0f) } } return buf } func (bcd *Bcd) Decode(buf []byte) string { var strbytes []byte for i := 0; i < len(buf); i++ { var b byte b = bcd.byte(int(buf[i] & 0x0f)) //if b == '?' { // return "" //} strbytes = append(strbytes, b) b = bcd.byte(int(buf[i] >> 4)) //if b == '?' { // return "" //} strbytes = append(strbytes, b) } return string(strbytes) }