xref: /linux/fs/nls/nls_base.c (revision 2da68a77)
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");
549