1 /* $Header: /home/yav/catty/fkiss/RCS/jiscode.c,v 1.3 2000/08/24 02:22:37 yav Exp $
2 * JIS code <-> Shift-JIS code
3 * written by yav <yav@bigfoot.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20 char id_jiscode[] = "$Id: jiscode.c,v 1.3 2000/08/24 02:22:37 yav Exp $";
21
is_sjis_1st(c)22 int is_sjis_1st(c)
23 int c;
24 {
25 return ((c)>=0x81 && (c)<=0x9f)||((c)>=0xe0 && (c)<=0xfc);
26 }
27
is_sjis_2nd(c)28 int is_sjis_2nd(c)
29 int c;
30 {
31 return ((c)>=0x40 && (c)<=0x7e)||((c)>=0x80 && (c)<=0xfc);
32 }
33
ysjis2jis(c)34 unsigned short ysjis2jis(c)
35 unsigned short c;
36 {
37 unsigned char h, l;
38 unsigned short dd;
39
40 h = c >> 8;
41 l = c & 0xff;
42 if (!is_sjis_1st(h) || !is_sjis_2nd(l))
43 return 0;
44 if (h >= 0xe0)
45 h -= 0x40;
46 if (l < 0x9f) {
47 if (l >= 0x80)
48 l -= 1;
49 dd = 0xe11f;
50 } else {
51 dd = 0xe07e;
52 }
53 return (h << 9) + l - dd;
54 }
55
56
yjis2sjis(c)57 unsigned short yjis2sjis(c)
58 unsigned short c;
59 {
60 unsigned short h, l;
61
62 l = c & 0xff;
63 h = c >> 8;
64 if ((h < 0x21)||(h > 0x7e)||(l < 0x21)||(l > 0x7e))
65 return 0;
66 if ((h & 1) != 0) {
67 l += 0x1f;
68 if (l >= 0x7f)
69 l++;
70 } else {
71 l += 0x7e;
72 }
73 h += 0xe1;
74 h >>= 1;
75 if (h >= 0xa0)
76 h += 0x40;
77 return (h << 8) + l;
78 }
79
80 /* End of file */
81