GNU Linux-libre 4.19.211-gnu1
[releases.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 #include <linux/kmod.h>
17 #include <linux/spinlock.h>
18 #include <asm/byteorder.h>
19
20 static struct nls_table default_table;
21 static struct nls_table *tables = &default_table;
22 static DEFINE_SPINLOCK(nls_lock);
23
24 /*
25  * Sample implementation from Unicode home page.
26  * http://www.stonehand.com/unicode/standard/fss-utf.html
27  */
28 struct utf8_table {
29         int     cmask;
30         int     cval;
31         int     shift;
32         long    lmask;
33         long    lval;
34 };
35
36 static const struct utf8_table utf8_table[] =
37 {
38     {0x80,  0x00,   0*6,    0x7F,           0,         /* 1 byte sequence */},
39     {0xE0,  0xC0,   1*6,    0x7FF,          0x80,      /* 2 byte sequence */},
40     {0xF0,  0xE0,   2*6,    0xFFFF,         0x800,     /* 3 byte sequence */},
41     {0xF8,  0xF0,   3*6,    0x1FFFFF,       0x10000,   /* 4 byte sequence */},
42     {0xFC,  0xF8,   4*6,    0x3FFFFFF,      0x200000,  /* 5 byte sequence */},
43     {0xFE,  0xFC,   5*6,    0x7FFFFFFF,     0x4000000, /* 6 byte sequence */},
44     {0,                                                /* end of table    */}
45 };
46
47 #define UNICODE_MAX     0x0010ffff
48 #define PLANE_SIZE      0x00010000
49
50 #define SURROGATE_MASK  0xfffff800
51 #define SURROGATE_PAIR  0x0000d800
52 #define SURROGATE_LOW   0x00000400
53 #define SURROGATE_BITS  0x000003ff
54
55 int utf8_to_utf32(const u8 *s, int inlen, unicode_t *pu)
56 {
57         unsigned long l;
58         int c0, c, nc;
59         const struct utf8_table *t;
60   
61         nc = 0;
62         c0 = *s;
63         l = c0;
64         for (t = utf8_table; t->cmask; t++) {
65                 nc++;
66                 if ((c0 & t->cmask) == t->cval) {
67                         l &= t->lmask;
68                         if (l < t->lval || l > UNICODE_MAX ||
69                                         (l & SURROGATE_MASK) == SURROGATE_PAIR)
70                                 return -1;
71                         *pu = (unicode_t) l;
72                         return nc;
73                 }
74                 if (inlen <= nc)
75                         return -1;
76                 s++;
77                 c = (*s ^ 0x80) & 0xFF;
78                 if (c & 0xC0)
79                         return -1;
80                 l = (l << 6) | c;
81         }
82         return -1;
83 }
84 EXPORT_SYMBOL(utf8_to_utf32);
85
86 int utf32_to_utf8(unicode_t u, u8 *s, int maxout)
87 {
88         unsigned long l;
89         int c, nc;
90         const struct utf8_table *t;
91
92         if (!s)
93                 return 0;
94
95         l = u;
96         if (l > UNICODE_MAX || (l & SURROGATE_MASK) == SURROGATE_PAIR)
97                 return -1;
98
99         nc = 0;
100         for (t = utf8_table; t->cmask && maxout; t++, maxout--) {
101                 nc++;
102                 if (l <= t->lmask) {
103                         c = t->shift;
104                         *s = (u8) (t->cval | (l >> c));
105                         while (c > 0) {
106                                 c -= 6;
107                                 s++;
108                                 *s = (u8) (0x80 | ((l >> c) & 0x3F));
109                         }
110                         return nc;
111                 }
112         }
113         return -1;
114 }
115 EXPORT_SYMBOL(utf32_to_utf8);
116
117 static inline void put_utf16(wchar_t *s, unsigned c, enum utf16_endian endian)
118 {
119         switch (endian) {
120         default:
121                 *s = (wchar_t) c;
122                 break;
123         case UTF16_LITTLE_ENDIAN:
124                 *s = __cpu_to_le16(c);
125                 break;
126         case UTF16_BIG_ENDIAN:
127                 *s = __cpu_to_be16(c);
128                 break;
129         }
130 }
131
132 int utf8s_to_utf16s(const u8 *s, int inlen, enum utf16_endian endian,
133                 wchar_t *pwcs, int maxout)
134 {
135         u16 *op;
136         int size;
137         unicode_t u;
138
139         op = pwcs;
140         while (inlen > 0 && maxout > 0 && *s) {
141                 if (*s & 0x80) {
142                         size = utf8_to_utf32(s, inlen, &u);
143                         if (size < 0)
144                                 return -EINVAL;
145                         s += size;
146                         inlen -= size;
147
148                         if (u >= PLANE_SIZE) {
149                                 if (maxout < 2)
150                                         break;
151                                 u -= PLANE_SIZE;
152                                 put_utf16(op++, SURROGATE_PAIR |
153                                                 ((u >> 10) & SURROGATE_BITS),
154                                                 endian);
155                                 put_utf16(op++, SURROGATE_PAIR |
156                                                 SURROGATE_LOW |
157                                                 (u & SURROGATE_BITS),
158                                                 endian);
159                                 maxout -= 2;
160                         } else {
161                                 put_utf16(op++, u, endian);
162                                 maxout--;
163                         }
164                 } else {
165                         put_utf16(op++, *s++, endian);
166                         inlen--;
167                         maxout--;
168                 }
169         }
170         return op - pwcs;
171 }
172 EXPORT_SYMBOL(utf8s_to_utf16s);
173
174 static inline unsigned long get_utf16(unsigned c, enum utf16_endian endian)
175 {
176         switch (endian) {
177         default:
178                 return c;
179         case UTF16_LITTLE_ENDIAN:
180                 return __le16_to_cpu(c);
181         case UTF16_BIG_ENDIAN:
182                 return __be16_to_cpu(c);
183         }
184 }
185
186 int utf16s_to_utf8s(const wchar_t *pwcs, int inlen, enum utf16_endian endian,
187                 u8 *s, int maxout)
188 {
189         u8 *op;
190         int size;
191         unsigned long u, v;
192
193         op = s;
194         while (inlen > 0 && maxout > 0) {
195                 u = get_utf16(*pwcs, endian);
196                 if (!u)
197                         break;
198                 pwcs++;
199                 inlen--;
200                 if (u > 0x7f) {
201                         if ((u & SURROGATE_MASK) == SURROGATE_PAIR) {
202                                 if (u & SURROGATE_LOW) {
203                                         /* Ignore character and move on */
204                                         continue;
205                                 }
206                                 if (inlen <= 0)
207                                         break;
208                                 v = get_utf16(*pwcs, endian);
209                                 if ((v & SURROGATE_MASK) != SURROGATE_PAIR ||
210                                                 !(v & SURROGATE_LOW)) {
211                                         /* Ignore character and move on */
212                                         continue;
213                                 }
214                                 u = PLANE_SIZE + ((u & SURROGATE_BITS) << 10)
215                                                 + (v & SURROGATE_BITS);
216                                 pwcs++;
217                                 inlen--;
218                         }
219                         size = utf32_to_utf8(u, op, maxout);
220                         if (size == -1) {
221                                 /* Ignore character and move on */
222                         } else {
223                                 op += size;
224                                 maxout -= size;
225                         }
226                 } else {
227                         *op++ = (u8) u;
228                         maxout--;
229                 }
230         }
231         return op - s;
232 }
233 EXPORT_SYMBOL(utf16s_to_utf8s);
234
235 int __register_nls(struct nls_table *nls, struct module *owner)
236 {
237         struct nls_table ** tmp = &tables;
238
239         if (nls->next)
240                 return -EBUSY;
241
242         nls->owner = owner;
243         spin_lock(&nls_lock);
244         while (*tmp) {
245                 if (nls == *tmp) {
246                         spin_unlock(&nls_lock);
247                         return -EBUSY;
248                 }
249                 tmp = &(*tmp)->next;
250         }
251         nls->next = tables;
252         tables = nls;
253         spin_unlock(&nls_lock);
254         return 0;       
255 }
256 EXPORT_SYMBOL(__register_nls);
257
258 int unregister_nls(struct nls_table * nls)
259 {
260         struct nls_table ** tmp = &tables;
261
262         spin_lock(&nls_lock);
263         while (*tmp) {
264                 if (nls == *tmp) {
265                         *tmp = nls->next;
266                         spin_unlock(&nls_lock);
267                         return 0;
268                 }
269                 tmp = &(*tmp)->next;
270         }
271         spin_unlock(&nls_lock);
272         return -EINVAL;
273 }
274
275 static struct nls_table *find_nls(char *charset)
276 {
277         struct nls_table *nls;
278         spin_lock(&nls_lock);
279         for (nls = tables; nls; nls = nls->next) {
280                 if (!strcmp(nls->charset, charset))
281                         break;
282                 if (nls->alias && !strcmp(nls->alias, charset))
283                         break;
284         }
285         if (nls && !try_module_get(nls->owner))
286                 nls = NULL;
287         spin_unlock(&nls_lock);
288         return nls;
289 }
290
291 struct nls_table *load_nls(char *charset)
292 {
293         return try_then_request_module(find_nls(charset), "nls_%s", charset);
294 }
295
296 void unload_nls(struct nls_table *nls)
297 {
298         if (nls)
299                 module_put(nls->owner);
300 }
301
302 static const wchar_t charset2uni[256] = {
303         /* 0x00*/
304         0x0000, 0x0001, 0x0002, 0x0003,
305         0x0004, 0x0005, 0x0006, 0x0007,
306         0x0008, 0x0009, 0x000a, 0x000b,
307         0x000c, 0x000d, 0x000e, 0x000f,
308         /* 0x10*/
309         0x0010, 0x0011, 0x0012, 0x0013,
310         0x0014, 0x0015, 0x0016, 0x0017,
311         0x0018, 0x0019, 0x001a, 0x001b,
312         0x001c, 0x001d, 0x001e, 0x001f,
313         /* 0x20*/
314         0x0020, 0x0021, 0x0022, 0x0023,
315         0x0024, 0x0025, 0x0026, 0x0027,
316         0x0028, 0x0029, 0x002a, 0x002b,
317         0x002c, 0x002d, 0x002e, 0x002f,
318         /* 0x30*/
319         0x0030, 0x0031, 0x0032, 0x0033,
320         0x0034, 0x0035, 0x0036, 0x0037,
321         0x0038, 0x0039, 0x003a, 0x003b,
322         0x003c, 0x003d, 0x003e, 0x003f,
323         /* 0x40*/
324         0x0040, 0x0041, 0x0042, 0x0043,
325         0x0044, 0x0045, 0x0046, 0x0047,
326         0x0048, 0x0049, 0x004a, 0x004b,
327         0x004c, 0x004d, 0x004e, 0x004f,
328         /* 0x50*/
329         0x0050, 0x0051, 0x0052, 0x0053,
330         0x0054, 0x0055, 0x0056, 0x0057,
331         0x0058, 0x0059, 0x005a, 0x005b,
332         0x005c, 0x005d, 0x005e, 0x005f,
333         /* 0x60*/
334         0x0060, 0x0061, 0x0062, 0x0063,
335         0x0064, 0x0065, 0x0066, 0x0067,
336         0x0068, 0x0069, 0x006a, 0x006b,
337         0x006c, 0x006d, 0x006e, 0x006f,
338         /* 0x70*/
339         0x0070, 0x0071, 0x0072, 0x0073,
340         0x0074, 0x0075, 0x0076, 0x0077,
341         0x0078, 0x0079, 0x007a, 0x007b,
342         0x007c, 0x007d, 0x007e, 0x007f,
343         /* 0x80*/
344         0x0080, 0x0081, 0x0082, 0x0083,
345         0x0084, 0x0085, 0x0086, 0x0087,
346         0x0088, 0x0089, 0x008a, 0x008b,
347         0x008c, 0x008d, 0x008e, 0x008f,
348         /* 0x90*/
349         0x0090, 0x0091, 0x0092, 0x0093,
350         0x0094, 0x0095, 0x0096, 0x0097,
351         0x0098, 0x0099, 0x009a, 0x009b,
352         0x009c, 0x009d, 0x009e, 0x009f,
353         /* 0xa0*/
354         0x00a0, 0x00a1, 0x00a2, 0x00a3,
355         0x00a4, 0x00a5, 0x00a6, 0x00a7,
356         0x00a8, 0x00a9, 0x00aa, 0x00ab,
357         0x00ac, 0x00ad, 0x00ae, 0x00af,
358         /* 0xb0*/
359         0x00b0, 0x00b1, 0x00b2, 0x00b3,
360         0x00b4, 0x00b5, 0x00b6, 0x00b7,
361         0x00b8, 0x00b9, 0x00ba, 0x00bb,
362         0x00bc, 0x00bd, 0x00be, 0x00bf,
363         /* 0xc0*/
364         0x00c0, 0x00c1, 0x00c2, 0x00c3,
365         0x00c4, 0x00c5, 0x00c6, 0x00c7,
366         0x00c8, 0x00c9, 0x00ca, 0x00cb,
367         0x00cc, 0x00cd, 0x00ce, 0x00cf,
368         /* 0xd0*/
369         0x00d0, 0x00d1, 0x00d2, 0x00d3,
370         0x00d4, 0x00d5, 0x00d6, 0x00d7,
371         0x00d8, 0x00d9, 0x00da, 0x00db,
372         0x00dc, 0x00dd, 0x00de, 0x00df,
373         /* 0xe0*/
374         0x00e0, 0x00e1, 0x00e2, 0x00e3,
375         0x00e4, 0x00e5, 0x00e6, 0x00e7,
376         0x00e8, 0x00e9, 0x00ea, 0x00eb,
377         0x00ec, 0x00ed, 0x00ee, 0x00ef,
378         /* 0xf0*/
379         0x00f0, 0x00f1, 0x00f2, 0x00f3,
380         0x00f4, 0x00f5, 0x00f6, 0x00f7,
381         0x00f8, 0x00f9, 0x00fa, 0x00fb,
382         0x00fc, 0x00fd, 0x00fe, 0x00ff,
383 };
384
385 static const unsigned char page00[256] = {
386         0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 0x00-0x07 */
387         0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 0x08-0x0f */
388         0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 0x10-0x17 */
389         0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 0x18-0x1f */
390         0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 0x20-0x27 */
391         0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 0x28-0x2f */
392         0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 0x30-0x37 */
393         0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 0x38-0x3f */
394         0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 0x40-0x47 */
395         0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 0x48-0x4f */
396         0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 0x50-0x57 */
397         0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 0x58-0x5f */
398         0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 0x60-0x67 */
399         0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 0x68-0x6f */
400         0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 0x70-0x77 */
401         0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 0x78-0x7f */
402
403         0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 0x80-0x87 */
404         0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 0x88-0x8f */
405         0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 0x90-0x97 */
406         0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 0x98-0x9f */
407         0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* 0xa0-0xa7 */
408         0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* 0xa8-0xaf */
409         0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* 0xb0-0xb7 */
410         0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* 0xb8-0xbf */
411         0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, /* 0xc0-0xc7 */
412         0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, /* 0xc8-0xcf */
413         0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, /* 0xd0-0xd7 */
414         0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, /* 0xd8-0xdf */
415         0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* 0xe0-0xe7 */
416         0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* 0xe8-0xef */
417         0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* 0xf0-0xf7 */
418         0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* 0xf8-0xff */
419 };
420
421 static const unsigned char *const page_uni2charset[256] = {
422         page00
423 };
424
425 static const unsigned char charset2lower[256] = {
426         0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 0x00-0x07 */
427         0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 0x08-0x0f */
428         0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 0x10-0x17 */
429         0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 0x18-0x1f */
430         0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 0x20-0x27 */
431         0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 0x28-0x2f */
432         0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 0x30-0x37 */
433         0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 0x38-0x3f */
434         0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 0x40-0x47 */
435         0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 0x48-0x4f */
436         0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 0x50-0x57 */
437         0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 0x58-0x5f */
438         0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 0x60-0x67 */
439         0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 0x68-0x6f */
440         0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 0x70-0x77 */
441         0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 0x78-0x7f */
442
443         0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 0x80-0x87 */
444         0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 0x88-0x8f */
445         0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 0x90-0x97 */
446         0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 0x98-0x9f */
447         0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* 0xa0-0xa7 */
448         0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* 0xa8-0xaf */
449         0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* 0xb0-0xb7 */
450         0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* 0xb8-0xbf */
451         0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, /* 0xc0-0xc7 */
452         0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, /* 0xc8-0xcf */
453         0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, /* 0xd0-0xd7 */
454         0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, /* 0xd8-0xdf */
455         0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* 0xe0-0xe7 */
456         0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* 0xe8-0xef */
457         0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* 0xf0-0xf7 */
458         0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* 0xf8-0xff */
459 };
460
461 static const unsigned char charset2upper[256] = {
462         0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 0x00-0x07 */
463         0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 0x08-0x0f */
464         0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 0x10-0x17 */
465         0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 0x18-0x1f */
466         0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 0x20-0x27 */
467         0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 0x28-0x2f */
468         0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 0x30-0x37 */
469         0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 0x38-0x3f */
470         0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 0x40-0x47 */
471         0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 0x48-0x4f */
472         0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 0x50-0x57 */
473         0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 0x58-0x5f */
474         0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 0x60-0x67 */
475         0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 0x68-0x6f */
476         0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 0x70-0x77 */
477         0x58, 0x59, 0x5a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 0x78-0x7f */
478
479         0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 0x80-0x87 */
480         0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 0x88-0x8f */
481         0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 0x90-0x97 */
482         0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 0x98-0x9f */
483         0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* 0xa0-0xa7 */
484         0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* 0xa8-0xaf */
485         0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* 0xb0-0xb7 */
486         0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* 0xb8-0xbf */
487         0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, /* 0xc0-0xc7 */
488         0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, /* 0xc8-0xcf */
489         0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, /* 0xd0-0xd7 */
490         0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, /* 0xd8-0xdf */
491         0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* 0xe0-0xe7 */
492         0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* 0xe8-0xef */
493         0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* 0xf0-0xf7 */
494         0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* 0xf8-0xff */
495 };
496
497
498 static int uni2char(wchar_t uni, unsigned char *out, int boundlen)
499 {
500         const unsigned char *uni2charset;
501         unsigned char cl = uni & 0x00ff;
502         unsigned char ch = (uni & 0xff00) >> 8;
503
504         if (boundlen <= 0)
505                 return -ENAMETOOLONG;
506
507         uni2charset = page_uni2charset[ch];
508         if (uni2charset && uni2charset[cl])
509                 out[0] = uni2charset[cl];
510         else
511                 return -EINVAL;
512         return 1;
513 }
514
515 static int char2uni(const unsigned char *rawstring, int boundlen, wchar_t *uni)
516 {
517         *uni = charset2uni[*rawstring];
518         if (*uni == 0x0000)
519                 return -EINVAL;
520         return 1;
521 }
522
523 static struct nls_table default_table = {
524         .charset        = "default",
525         .uni2char       = uni2char,
526         .char2uni       = char2uni,
527         .charset2lower  = charset2lower,
528         .charset2upper  = charset2upper,
529 };
530
531 /* Returns a simple default translation table */
532 struct nls_table *load_nls_default(void)
533 {
534         struct nls_table *default_nls;
535         
536         default_nls = load_nls(CONFIG_NLS_DEFAULT);
537         if (default_nls != NULL)
538                 return default_nls;
539         else
540                 return &default_table;
541 }
542
543 EXPORT_SYMBOL(unregister_nls);
544 EXPORT_SYMBOL(unload_nls);
545 EXPORT_SYMBOL(load_nls);
546 EXPORT_SYMBOL(load_nls_default);
547
548 MODULE_LICENSE("Dual BSD/GPL");