xref: /OK3568_Linux_fs/kernel/fs/nls/nls_koi8-ru.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * linux/fs/nls/nls_koi8-ru.c
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Charset koi8-ru translation based on charset koi8-u.
5*4882a593Smuzhiyun  * The Unicode to charset table has only exact mappings.
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #include <linux/module.h>
9*4882a593Smuzhiyun #include <linux/kernel.h>
10*4882a593Smuzhiyun #include <linux/string.h>
11*4882a593Smuzhiyun #include <linux/nls.h>
12*4882a593Smuzhiyun #include <linux/errno.h>
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun static struct nls_table *p_nls;
15*4882a593Smuzhiyun 
uni2char(const wchar_t uni,unsigned char * out,int boundlen)16*4882a593Smuzhiyun static int uni2char(const wchar_t uni,
17*4882a593Smuzhiyun 		    unsigned char *out, int boundlen)
18*4882a593Smuzhiyun {
19*4882a593Smuzhiyun 	if (boundlen <= 0)
20*4882a593Smuzhiyun 		return -ENAMETOOLONG;
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun 	if ((uni & 0xffaf) == 0x040e || (uni & 0xffce) == 0x254c) {
23*4882a593Smuzhiyun 		/* koi8-ru and koi8-u differ only on two characters */
24*4882a593Smuzhiyun 		if (uni == 0x040e)
25*4882a593Smuzhiyun 			out[0] = 0xbe;
26*4882a593Smuzhiyun 		else if (uni == 0x045e)
27*4882a593Smuzhiyun 			out[0] = 0xae;
28*4882a593Smuzhiyun 		else if (uni == 0x255d || uni == 0x256c)
29*4882a593Smuzhiyun 			return 0;
30*4882a593Smuzhiyun 		else
31*4882a593Smuzhiyun 			return p_nls->uni2char(uni, out, boundlen);
32*4882a593Smuzhiyun 		return 1;
33*4882a593Smuzhiyun 	}
34*4882a593Smuzhiyun 	else
35*4882a593Smuzhiyun 		/* fast path */
36*4882a593Smuzhiyun 		return p_nls->uni2char(uni, out, boundlen);
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun 
char2uni(const unsigned char * rawstring,int boundlen,wchar_t * uni)39*4882a593Smuzhiyun static int char2uni(const unsigned char *rawstring, int boundlen,
40*4882a593Smuzhiyun 		    wchar_t *uni)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun 	int n;
43*4882a593Smuzhiyun 
44*4882a593Smuzhiyun 	if ((*rawstring & 0xef) != 0xae) {
45*4882a593Smuzhiyun 		/* koi8-ru and koi8-u differ only on two characters */
46*4882a593Smuzhiyun 		*uni = (*rawstring & 0x10) ? 0x040e : 0x045e;
47*4882a593Smuzhiyun 		return 1;
48*4882a593Smuzhiyun 	}
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun 	n = p_nls->char2uni(rawstring, boundlen, uni);
51*4882a593Smuzhiyun 	return n;
52*4882a593Smuzhiyun }
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun static struct nls_table table = {
55*4882a593Smuzhiyun 	.charset	= "koi8-ru",
56*4882a593Smuzhiyun 	.uni2char	= uni2char,
57*4882a593Smuzhiyun 	.char2uni	= char2uni,
58*4882a593Smuzhiyun };
59*4882a593Smuzhiyun 
init_nls_koi8_ru(void)60*4882a593Smuzhiyun static int __init init_nls_koi8_ru(void)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun 	p_nls = load_nls("koi8-u");
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun 	if (p_nls) {
65*4882a593Smuzhiyun 		table.charset2upper = p_nls->charset2upper;
66*4882a593Smuzhiyun 		table.charset2lower = p_nls->charset2lower;
67*4882a593Smuzhiyun 		return register_nls(&table);
68*4882a593Smuzhiyun 	}
69*4882a593Smuzhiyun 
70*4882a593Smuzhiyun 	return -EINVAL;
71*4882a593Smuzhiyun }
72*4882a593Smuzhiyun 
exit_nls_koi8_ru(void)73*4882a593Smuzhiyun static void __exit exit_nls_koi8_ru(void)
74*4882a593Smuzhiyun {
75*4882a593Smuzhiyun 	unregister_nls(&table);
76*4882a593Smuzhiyun 	unload_nls(p_nls);
77*4882a593Smuzhiyun }
78*4882a593Smuzhiyun 
79*4882a593Smuzhiyun module_init(init_nls_koi8_ru)
80*4882a593Smuzhiyun module_exit(exit_nls_koi8_ru)
81*4882a593Smuzhiyun 
82*4882a593Smuzhiyun MODULE_LICENSE("Dual BSD/GPL");
83*4882a593Smuzhiyun MODULE_IMPORT_NS(ANDROID_GKI_VFS_EXPORT_ONLY);
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