1 /*
2  * "streamable kanji code filter and converter"
3  * Copyright (c) 1998-2002 HappySize, Inc. All rights reserved.
4  *
5  * LICENSE NOTICES
6  *
7  * This file is part of "streamable kanji code filter and converter",
8  * which is distributed under the terms of GNU Lesser General Public
9  * License (version 2) as published by the Free Software Foundation.
10  *
11  * This software is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with "streamable kanji code filter and converter";
18  * if not, write to the Free Software Foundation, Inc., 59 Temple Place,
19  * Suite 330, Boston, MA  02111-1307  USA
20  *
21  * The author of this part: Den V. Tsopa <tdv@edisoft.ru>
22  * Adaption for CP850: D. Giffeler <dg@artegic.de>
23  *
24  */
25 
26 #ifdef HAVE_CONFIG_H
27 #include "config.h"
28 #endif
29 
30 #include "mbfilter.h"
31 #include "mbfilter_cp850.h"
32 #include "unicode_table_cp850.h"
33 
34 static int mbfl_filt_ident_cp850(int c, mbfl_identify_filter *filter);
35 
36 static const char *mbfl_encoding_cp850_aliases[] = {"CP850", "CP-850", "IBM850", "IBM-850", NULL};
37 
38 const mbfl_encoding mbfl_encoding_cp850 = {
39 	mbfl_no_encoding_cp850,
40 	"CP850",
41 	"CP850",
42 	(const char *(*)[])&mbfl_encoding_cp850_aliases,
43 	NULL,
44 	MBFL_ENCTYPE_SBCS
45 };
46 
47 const struct mbfl_identify_vtbl vtbl_identify_cp850 = {
48 	mbfl_no_encoding_cp850,
49 	mbfl_filt_ident_common_ctor,
50 	mbfl_filt_ident_common_dtor,
51 	mbfl_filt_ident_cp850
52 };
53 
54 const struct mbfl_convert_vtbl vtbl_wchar_cp850 = {
55 	mbfl_no_encoding_wchar,
56 	mbfl_no_encoding_cp850,
57 	mbfl_filt_conv_common_ctor,
58 	mbfl_filt_conv_common_dtor,
59 	mbfl_filt_conv_wchar_cp850,
60 	mbfl_filt_conv_common_flush
61 };
62 
63 const struct mbfl_convert_vtbl vtbl_cp850_wchar = {
64 	mbfl_no_encoding_cp850,
65 	mbfl_no_encoding_wchar,
66 	mbfl_filt_conv_common_ctor,
67 	mbfl_filt_conv_common_dtor,
68 	mbfl_filt_conv_cp850_wchar,
69 	mbfl_filt_conv_common_flush
70 };
71 
72 #define CK(statement)	do { if ((statement) < 0) return (-1); } while (0)
73 
74 /*
75  * cp850 => wchar
76  */
77 int
mbfl_filt_conv_cp850_wchar(int c,mbfl_convert_filter * filter)78 mbfl_filt_conv_cp850_wchar(int c, mbfl_convert_filter *filter)
79 {
80 	int s;
81 
82 	if (c >= 0 && c < cp850_ucs_table_min) {
83 		s = c;
84 	} else if (c >= cp850_ucs_table_min && c < 0x100) {
85 		s = cp850_ucs_table[c - cp850_ucs_table_min];
86 		if (s <= 0) {
87 			s = c;
88 			s &= MBFL_WCSPLANE_MASK;
89 			s |= MBFL_WCSPLANE_CP850;
90 		}
91 	} else {
92 		s = c;
93 		s &= MBFL_WCSGROUP_MASK;
94 		s |= MBFL_WCSGROUP_THROUGH;
95 	}
96 
97 	CK((*filter->output_function)(s, filter->data));
98 
99 	return c;
100 }
101 
102 /*
103  * wchar => cp850
104  */
105 int
mbfl_filt_conv_wchar_cp850(int c,mbfl_convert_filter * filter)106 mbfl_filt_conv_wchar_cp850(int c, mbfl_convert_filter *filter)
107 {
108 	int s, n;
109 
110 	if (c < 0x80) {
111 		s = c;
112 	} else {
113 		s = -1;
114 		n = cp850_ucs_table_len-1;
115 		while (n >= 0) {
116 			if (c == cp850_ucs_table[n]) {
117 				s = cp850_ucs_table_min + n;
118 				break;
119 			}
120 			n--;
121 		}
122 		if (s <= 0 && (c & ~MBFL_WCSPLANE_MASK) == MBFL_WCSPLANE_CP850) {
123 			s = c & MBFL_WCSPLANE_MASK;
124 		}
125 	}
126 
127 	if (s >= 0) {
128 		CK((*filter->output_function)(s, filter->data));
129 	} else {
130 		if (filter->illegal_mode != MBFL_OUTPUTFILTER_ILLEGAL_MODE_NONE) {
131 			CK(mbfl_filt_conv_illegal_output(c, filter));
132 		}
133 	}
134 
135 	return c;
136 }
137 
mbfl_filt_ident_cp850(int c,mbfl_identify_filter * filter)138 static int mbfl_filt_ident_cp850(int c, mbfl_identify_filter *filter)
139 {
140 	if (c >= 0x80 && c < 0xff)
141 		filter->flag = 0;
142 	else
143 		filter->flag = 1; /* not it */
144 	return c;
145 }
146