1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * Module for handling utf8 just like any other charset.
3*4882a593Smuzhiyun * By Urban Widmark 2000
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun #include <linux/module.h>
7*4882a593Smuzhiyun #include <linux/kernel.h>
8*4882a593Smuzhiyun #include <linux/string.h>
9*4882a593Smuzhiyun #include <linux/nls.h>
10*4882a593Smuzhiyun #include <linux/errno.h>
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun static unsigned char identity[256];
13*4882a593Smuzhiyun
uni2char(wchar_t uni,unsigned char * out,int boundlen)14*4882a593Smuzhiyun static int uni2char(wchar_t uni, unsigned char *out, int boundlen)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun int n;
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun if (boundlen <= 0)
19*4882a593Smuzhiyun return -ENAMETOOLONG;
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun n = utf32_to_utf8(uni, out, boundlen);
22*4882a593Smuzhiyun if (n < 0) {
23*4882a593Smuzhiyun *out = '?';
24*4882a593Smuzhiyun return -EINVAL;
25*4882a593Smuzhiyun }
26*4882a593Smuzhiyun return n;
27*4882a593Smuzhiyun }
28*4882a593Smuzhiyun
char2uni(const unsigned char * rawstring,int boundlen,wchar_t * uni)29*4882a593Smuzhiyun static int char2uni(const unsigned char *rawstring, int boundlen, wchar_t *uni)
30*4882a593Smuzhiyun {
31*4882a593Smuzhiyun int n;
32*4882a593Smuzhiyun unicode_t u;
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun n = utf8_to_utf32(rawstring, boundlen, &u);
35*4882a593Smuzhiyun if (n < 0 || u > MAX_WCHAR_T) {
36*4882a593Smuzhiyun *uni = 0x003f; /* ? */
37*4882a593Smuzhiyun return -EINVAL;
38*4882a593Smuzhiyun }
39*4882a593Smuzhiyun *uni = (wchar_t) u;
40*4882a593Smuzhiyun return n;
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun static struct nls_table table = {
44*4882a593Smuzhiyun .charset = "utf8",
45*4882a593Smuzhiyun .uni2char = uni2char,
46*4882a593Smuzhiyun .char2uni = char2uni,
47*4882a593Smuzhiyun .charset2lower = identity, /* no conversion */
48*4882a593Smuzhiyun .charset2upper = identity,
49*4882a593Smuzhiyun };
50*4882a593Smuzhiyun
init_nls_utf8(void)51*4882a593Smuzhiyun static int __init init_nls_utf8(void)
52*4882a593Smuzhiyun {
53*4882a593Smuzhiyun int i;
54*4882a593Smuzhiyun for (i=0; i<256; i++)
55*4882a593Smuzhiyun identity[i] = i;
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun return register_nls(&table);
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun
exit_nls_utf8(void)60*4882a593Smuzhiyun static void __exit exit_nls_utf8(void)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun unregister_nls(&table);
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun module_init(init_nls_utf8)
66*4882a593Smuzhiyun module_exit(exit_nls_utf8)
67*4882a593Smuzhiyun MODULE_LICENSE("Dual BSD/GPL");
68