1 /* 2 * linux/fs/nls_koi8-ru.c 3 * 4 * Charset koi8-ru translation based on charset koi8-u. 5 * The Unicode to charset table has only exact mappings. 6 */ 7 8 #include <linux/module.h> 9 #include <linux/kernel.h> 10 #include <linux/string.h> 11 #include <linux/nls.h> 12 #include <linux/errno.h> 13 14 static struct nls_table *p_nls; 15 16 static int uni2char(const wchar_t uni, 17 unsigned char *out, int boundlen) 18 { 19 if (boundlen <= 0) 20 return -ENAMETOOLONG; 21 22 if ((uni & 0xffaf) == 0x040e || (uni & 0xffce) == 0x254c) { 23 /* koi8-ru and koi8-u differ only on two characters */ 24 if (uni == 0x040e) 25 out[0] = 0xbe; 26 else if (uni == 0x045e) 27 out[0] = 0xae; 28 else if (uni == 0x255d || uni == 0x256c) 29 return 0; 30 else 31 return p_nls->uni2char(uni, out, boundlen); 32 return 1; 33 } 34 else 35 /* fast path */ 36 return p_nls->uni2char(uni, out, boundlen); 37 } 38 39 static int char2uni(const unsigned char *rawstring, int boundlen, 40 wchar_t *uni) 41 { 42 int n; 43 44 if ((*rawstring & 0xef) != 0xae) { 45 /* koi8-ru and koi8-u differ only on two characters */ 46 *uni = (*rawstring & 0x10) ? 0x040e : 0x045e; 47 return 1; 48 } 49 50 n = p_nls->char2uni(rawstring, boundlen, uni); 51 return n; 52 } 53 54 static struct nls_table table = { 55 .charset = "koi8-ru", 56 .uni2char = uni2char, 57 .char2uni = char2uni, 58 .owner = THIS_MODULE, 59 }; 60 61 static int __init init_nls_koi8_ru(void) 62 { 63 p_nls = load_nls("koi8-u"); 64 65 if (p_nls) { 66 table.charset2upper = p_nls->charset2upper; 67 table.charset2lower = p_nls->charset2lower; 68 return register_nls(&table); 69 } 70 71 return -EINVAL; 72 } 73 74 static void __exit exit_nls_koi8_ru(void) 75 { 76 unregister_nls(&table); 77 unload_nls(p_nls); 78 } 79 80 module_init(init_nls_koi8_ru) 81 module_exit(exit_nls_koi8_ru) 82 83 MODULE_LICENSE("Dual BSD/GPL"); 84