sparse pointer use of zero as null
[linux-3.10.git] / fs / nls / nls_base.c
1 /*
2  * linux/fs/nls/nls_base.c
3  *
4  * Native language support--charsets and unicode translations.
5  * By Gordon Chaffee 1996, 1997
6  *
7  * Unicode based case conversion 1999 by Wolfram Pienkoss
8  *
9  */
10
11 #include <linux/module.h>
12 #include <linux/string.h>
13 #include <linux/nls.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #ifdef CONFIG_KMOD
17 #include <linux/kmod.h>
18 #endif
19 #include <linux/spinlock.h>
20
21 static struct nls_table default_table;
22 static struct nls_table *tables = &default_table;
23 static DEFINE_SPINLOCK(nls_lock);
24
25 /*
26  * Sample implementation from Unicode home page.
27  * http://www.stonehand.com/unicode/standard/fss-utf.html
28  */
29 struct utf8_table {
30         int     cmask;
31         int     cval;
32         int     shift;
33         long    lmask;
34         long    lval;
35 };
36
37 static const struct utf8_table utf8_table[] =
38 {
39     {0x80,  0x00,   0*6,    0x7F,           0,         /* 1 byte sequence */},
40     {0xE0,  0xC0,   1*6,    0x7FF,          0x80,      /* 2 byte sequence */},
41     {0xF0,  0xE0,   2*6,    0xFFFF,         0x800,     /* 3 byte sequence */},
42     {0xF8,  0xF0,   3*6,    0x1FFFFF,       0x10000,   /* 4 byte sequence */},
43     {0xFC,  0xF8,   4*6,    0x3FFFFFF,      0x200000,  /* 5 byte sequence */},
44     {0xFE,  0xFC,   5*6,    0x7FFFFFFF,     0x4000000, /* 6 byte sequence */},
45     {0,                                                /* end of table    */}
46 };
47
48 int
49 utf8_mbtowc(wchar_t *p, const __u8 *s, int n)
50 {
51         long l;
52         int c0, c, nc;
53         const struct utf8_table *t;
54   
55         nc = 0;
56         c0 = *s;
57         l = c0;
58         for (t = utf8_table; t->cmask; t++) {
59                 nc++;
60                 if ((c0 & t->cmask) == t->cval) {
61                         l &= t->lmask;
62                         if (l < t->lval)
63                                 return -1;
64                         *p = l;
65                         return nc;
66                 }
67                 if (n <= nc)
68                         return -1;
69                 s++;
70                 c = (*s ^ 0x80) & 0xFF;
71                 if (c & 0xC0)
72                         return -1;
73                 l = (l << 6) | c;
74         }
75         return -1;
76 }
77
78 int
79 utf8_mbstowcs(wchar_t *pwcs, const __u8 *s, int n)
80 {
81         __u16 *op;
82         const __u8 *ip;
83         int size;
84
85         op = pwcs;
86         ip = s;
87         while (*ip && n > 0) {
88                 if (*ip & 0x80) {
89                         size = utf8_mbtowc(op, ip, n);
90                         if (size == -1) {
91                                 /* Ignore character and move on */
92                                 ip++;
93                                 n--;
94                         } else {
95                                 op++;
96                                 ip += size;
97                                 n -= size;
98                         }
99                 } else {
100                         *op++ = *ip++;
101                         n--;
102                 }
103         }
104         return (op - pwcs);
105 }
106
107 int
108 utf8_wctomb(__u8 *s, wchar_t wc, int maxlen)
109 {
110         long l;
111         int c, nc;
112         const struct utf8_table *t;
113   
114         if (!s)
115                 return 0;
116   
117         l = wc;
118         nc = 0;
119         for (t = utf8_table; t->cmask && maxlen; t++, maxlen--) {
120                 nc++;
121                 if (l <= t->lmask) {
122                         c = t->shift;
123                         *s = t->cval | (l >> c);
124                         while (c > 0) {
125                                 c -= 6;
126                                 s++;
127                                 *s = 0x80 | ((l >> c) & 0x3F);
128                         }
129                         return nc;
130                 }
131         }
132         return -1;
133 }
134
135 int
136 utf8_wcstombs(__u8 *s, const wchar_t *pwcs, int maxlen)
137 {
138         const __u16 *ip;
139         __u8 *op;
140         int size;
141
142         op = s;
143         ip = pwcs;
144         while (*ip && maxlen > 0) {
145                 if (*ip > 0x7f) {
146                         size = utf8_wctomb(op, *ip, maxlen);
147                         if (size == -1) {
148                                 /* Ignore character and move on */
149                                 maxlen--;
150                         } else {
151                                 op += size;
152                                 maxlen -= size;
153                         }
154                 } else {
155                         *op++ = (__u8) *ip;
156                 }
157                 ip++;
158         }
159         return (op - s);
160 }
161
162 int register_nls(struct nls_table * nls)
163 {
164         struct nls_table ** tmp = &tables;
165
166         if (nls->next)
167                 return -EBUSY;
168
169         spin_lock(&nls_lock);
170         while (*tmp) {
171                 if (nls == *tmp) {
172                         spin_unlock(&nls_lock);
173                         return -EBUSY;
174                 }
175                 tmp = &(*tmp)->next;
176         }
177         nls->next = tables;
178         tables = nls;
179         spin_unlock(&nls_lock);
180         return 0;       
181 }
182
183 int unregister_nls(struct nls_table * nls)
184 {
185         struct nls_table ** tmp = &tables;
186
187         spin_lock(&nls_lock);
188         while (*tmp) {
189                 if (nls == *tmp) {
190                         *tmp = nls->next;
191                         spin_unlock(&nls_lock);
192                         return 0;
193                 }
194                 tmp = &(*tmp)->next;
195         }
196         spin_unlock(&nls_lock);
197         return -EINVAL;
198 }
199
200 static struct nls_table *find_nls(char *charset)
201 {
202         struct nls_table *nls;
203         spin_lock(&nls_lock);
204         for (nls = tables; nls; nls = nls->next) {
205                 if (!strcmp(nls->charset, charset))
206                         break;
207                 if (nls->alias && !strcmp(nls->alias, charset))
208                         break;
209         }
210         if (nls && !try_module_get(nls->owner))
211                 nls = NULL;
212         spin_unlock(&nls_lock);
213         return nls;
214 }
215
216 struct nls_table *load_nls(char *charset)
217 {
218         struct nls_table *nls;
219 #ifdef CONFIG_KMOD
220         int ret;
221 #endif
222
223         nls = find_nls(charset);
224         if (nls)
225                 return nls;
226
227 #ifdef CONFIG_KMOD
228         ret = request_module("nls_%s", charset);
229         if (ret != 0) {
230                 printk("Unable to load NLS charset %s\n", charset);
231                 return NULL;
232         }
233         nls = find_nls(charset);
234 #endif
235         return nls;
236 }
237
238 void unload_nls(struct nls_table *nls)
239 {
240         module_put(nls->owner);
241 }
242
243 static const wchar_t charset2uni[256] = {
244         /* 0x00*/
245         0x0000, 0x0001, 0x0002, 0x0003,
246         0x0004, 0x0005, 0x0006, 0x0007,
247         0x0008, 0x0009, 0x000a, 0x000b,
248         0x000c, 0x000d, 0x000e, 0x000f,
249         /* 0x10*/
250         0x0010, 0x0011, 0x0012, 0x0013,
251         0x0014, 0x0015, 0x0016, 0x0017,
252         0x0018, 0x0019, 0x001a, 0x001b,
253         0x001c, 0x001d, 0x001e, 0x001f,
254         /* 0x20*/
255         0x0020, 0x0021, 0x0022, 0x0023,
256         0x0024, 0x0025, 0x0026, 0x0027,
257         0x0028, 0x0029, 0x002a, 0x002b,
258         0x002c, 0x002d, 0x002e, 0x002f,
259         /* 0x30*/
260         0x0030, 0x0031, 0x0032, 0x0033,
261         0x0034, 0x0035, 0x0036, 0x0037,
262         0x0038, 0x0039, 0x003a, 0x003b,
263         0x003c, 0x003d, 0x003e, 0x003f,
264         /* 0x40*/
265         0x0040, 0x0041, 0x0042, 0x0043,
266         0x0044, 0x0045, 0x0046, 0x0047,
267         0x0048, 0x0049, 0x004a, 0x004b,
268         0x004c, 0x004d, 0x004e, 0x004f,
269         /* 0x50*/
270         0x0050, 0x0051, 0x0052, 0x0053,
271         0x0054, 0x0055, 0x0056, 0x0057,
272         0x0058, 0x0059, 0x005a, 0x005b,
273         0x005c, 0x005d, 0x005e, 0x005f,
274         /* 0x60*/
275         0x0060, 0x0061, 0x0062, 0x0063,
276         0x0064, 0x0065, 0x0066, 0x0067,
277         0x0068, 0x0069, 0x006a, 0x006b,
278         0x006c, 0x006d, 0x006e, 0x006f,
279         /* 0x70*/
280         0x0070, 0x0071, 0x0072, 0x0073,
281         0x0074, 0x0075, 0x0076, 0x0077,
282         0x0078, 0x0079, 0x007a, 0x007b,
283         0x007c, 0x007d, 0x007e, 0x007f,
284         /* 0x80*/
285         0x0080, 0x0081, 0x0082, 0x0083,
286         0x0084, 0x0085, 0x0086, 0x0087,
287         0x0088, 0x0089, 0x008a, 0x008b,
288         0x008c, 0x008d, 0x008e, 0x008f,
289         /* 0x90*/
290         0x0090, 0x0091, 0x0092, 0x0093,
291         0x0094, 0x0095, 0x0096, 0x0097,
292         0x0098, 0x0099, 0x009a, 0x009b,
293         0x009c, 0x009d, 0x009e, 0x009f,
294         /* 0xa0*/
295         0x00a0, 0x00a1, 0x00a2, 0x00a3,
296         0x00a4, 0x00a5, 0x00a6, 0x00a7,
297         0x00a8, 0x00a9, 0x00aa, 0x00ab,
298         0x00ac, 0x00ad, 0x00ae, 0x00af,
299         /* 0xb0*/
300         0x00b0, 0x00b1, 0x00b2, 0x00b3,
301         0x00b4, 0x00b5, 0x00b6, 0x00b7,
302         0x00b8, 0x00b9, 0x00ba, 0x00bb,
303         0x00bc, 0x00bd, 0x00be, 0x00bf,
304         /* 0xc0*/
305         0x00c0, 0x00c1, 0x00c2, 0x00c3,
306         0x00c4, 0x00c5, 0x00c6, 0x00c7,
307         0x00c8, 0x00c9, 0x00ca, 0x00cb,
308         0x00cc, 0x00cd, 0x00ce, 0x00cf,
309         /* 0xd0*/
310         0x00d0, 0x00d1, 0x00d2, 0x00d3,
311         0x00d4, 0x00d5, 0x00d6, 0x00d7,
312         0x00d8, 0x00d9, 0x00da, 0x00db,
313         0x00dc, 0x00dd, 0x00de, 0x00df,
314         /* 0xe0*/
315         0x00e0, 0x00e1, 0x00e2, 0x00e3,
316         0x00e4, 0x00e5, 0x00e6, 0x00e7,
317         0x00e8, 0x00e9, 0x00ea, 0x00eb,
318         0x00ec, 0x00ed, 0x00ee, 0x00ef,
319         /* 0xf0*/
320         0x00f0, 0x00f1, 0x00f2, 0x00f3,
321         0x00f4, 0x00f5, 0x00f6, 0x00f7,
322         0x00f8, 0x00f9, 0x00fa, 0x00fb,
323         0x00fc, 0x00fd, 0x00fe, 0x00ff,
324 };
325
326 static const unsigned char page00[256] = {
327         0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 0x00-0x07 */
328         0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 0x08-0x0f */
329         0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 0x10-0x17 */
330         0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 0x18-0x1f */
331         0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 0x20-0x27 */
332         0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 0x28-0x2f */
333         0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 0x30-0x37 */
334         0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 0x38-0x3f */
335         0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 0x40-0x47 */
336         0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 0x48-0x4f */
337         0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 0x50-0x57 */
338         0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 0x58-0x5f */
339         0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 0x60-0x67 */
340         0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 0x68-0x6f */
341         0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 0x70-0x77 */
342         0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 0x78-0x7f */
343
344         0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 0x80-0x87 */
345         0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 0x88-0x8f */
346         0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 0x90-0x97 */
347         0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 0x98-0x9f */
348         0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* 0xa0-0xa7 */
349         0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* 0xa8-0xaf */
350         0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* 0xb0-0xb7 */
351         0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* 0xb8-0xbf */
352         0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, /* 0xc0-0xc7 */
353         0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, /* 0xc8-0xcf */
354         0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, /* 0xd0-0xd7 */
355         0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, /* 0xd8-0xdf */
356         0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* 0xe0-0xe7 */
357         0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* 0xe8-0xef */
358         0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* 0xf0-0xf7 */
359         0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* 0xf8-0xff */
360 };
361
362 static const unsigned char *const page_uni2charset[256] = {
363         page00
364 };
365
366 static const unsigned char charset2lower[256] = {
367         0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 0x00-0x07 */
368         0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 0x08-0x0f */
369         0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 0x10-0x17 */
370         0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 0x18-0x1f */
371         0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 0x20-0x27 */
372         0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 0x28-0x2f */
373         0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 0x30-0x37 */
374         0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 0x38-0x3f */
375         0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 0x40-0x47 */
376         0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 0x48-0x4f */
377         0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 0x50-0x57 */
378         0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 0x58-0x5f */
379         0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 0x60-0x67 */
380         0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 0x68-0x6f */
381         0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 0x70-0x77 */
382         0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 0x78-0x7f */
383
384         0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 0x80-0x87 */
385         0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 0x88-0x8f */
386         0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 0x90-0x97 */
387         0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 0x98-0x9f */
388         0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* 0xa0-0xa7 */
389         0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* 0xa8-0xaf */
390         0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* 0xb0-0xb7 */
391         0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* 0xb8-0xbf */
392         0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, /* 0xc0-0xc7 */
393         0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, /* 0xc8-0xcf */
394         0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, /* 0xd0-0xd7 */
395         0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, /* 0xd8-0xdf */
396         0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* 0xe0-0xe7 */
397         0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* 0xe8-0xef */
398         0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* 0xf0-0xf7 */
399         0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* 0xf8-0xff */
400 };
401
402 static const unsigned char charset2upper[256] = {
403         0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 0x00-0x07 */
404         0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 0x08-0x0f */
405         0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 0x10-0x17 */
406         0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 0x18-0x1f */
407         0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 0x20-0x27 */
408         0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 0x28-0x2f */
409         0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 0x30-0x37 */
410         0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 0x38-0x3f */
411         0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 0x40-0x47 */
412         0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 0x48-0x4f */
413         0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 0x50-0x57 */
414         0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 0x58-0x5f */
415         0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 0x60-0x67 */
416         0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 0x68-0x6f */
417         0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 0x70-0x77 */
418         0x58, 0x59, 0x5a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 0x78-0x7f */
419
420         0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 0x80-0x87 */
421         0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 0x88-0x8f */
422         0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 0x90-0x97 */
423         0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 0x98-0x9f */
424         0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* 0xa0-0xa7 */
425         0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* 0xa8-0xaf */
426         0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* 0xb0-0xb7 */
427         0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* 0xb8-0xbf */
428         0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, /* 0xc0-0xc7 */
429         0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, /* 0xc8-0xcf */
430         0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, /* 0xd0-0xd7 */
431         0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, /* 0xd8-0xdf */
432         0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* 0xe0-0xe7 */
433         0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* 0xe8-0xef */
434         0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* 0xf0-0xf7 */
435         0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* 0xf8-0xff */
436 };
437
438
439 static int uni2char(wchar_t uni, unsigned char *out, int boundlen)
440 {
441         const unsigned char *uni2charset;
442         unsigned char cl = uni & 0x00ff;
443         unsigned char ch = (uni & 0xff00) >> 8;
444
445         if (boundlen <= 0)
446                 return -ENAMETOOLONG;
447
448         uni2charset = page_uni2charset[ch];
449         if (uni2charset && uni2charset[cl])
450                 out[0] = uni2charset[cl];
451         else
452                 return -EINVAL;
453         return 1;
454 }
455
456 static int char2uni(const unsigned char *rawstring, int boundlen, wchar_t *uni)
457 {
458         *uni = charset2uni[*rawstring];
459         if (*uni == 0x0000)
460                 return -EINVAL;
461         return 1;
462 }
463
464 static struct nls_table default_table = {
465         .charset        = "default",
466         .uni2char       = uni2char,
467         .char2uni       = char2uni,
468         .charset2lower  = charset2lower,
469         .charset2upper  = charset2upper,
470 };
471
472 /* Returns a simple default translation table */
473 struct nls_table *load_nls_default(void)
474 {
475         struct nls_table *default_nls;
476         
477         default_nls = load_nls(CONFIG_NLS_DEFAULT);
478         if (default_nls != NULL)
479                 return default_nls;
480         else
481                 return &default_table;
482 }
483
484 EXPORT_SYMBOL(register_nls);
485 EXPORT_SYMBOL(unregister_nls);
486 EXPORT_SYMBOL(unload_nls);
487 EXPORT_SYMBOL(load_nls);
488 EXPORT_SYMBOL(load_nls_default);
489 EXPORT_SYMBOL(utf8_mbtowc);
490 EXPORT_SYMBOL(utf8_mbstowcs);
491 EXPORT_SYMBOL(utf8_wctomb);
492 EXPORT_SYMBOL(utf8_wcstombs);
493
494 MODULE_LICENSE("Dual BSD/GPL");