1 #include <lib9.h>
2 static char t16e[] = "0123456789ABCDEF";
3 
4 int
5 dec16(uchar *out, int lim, char *in, int n)
6 {
7 	int c, w = 0, i = 0;
8 	uchar *start = out;
9 	uchar *eout = out + lim;
10 
11 	while(n-- > 0){
12 		c = *in++;
13 		if('0' <= c && c <= '9')
14 			c = c - '0';
15 		else if('a' <= c && c <= 'z')
16 			c = c - 'a' + 10;
17 		else if('A' <= c && c <= 'Z')
18 			c = c - 'A' + 10;
19 		else
20 			continue;
21 		w = (w<<4) + c;
22 		i++;
23 		if(i == 2){
24 			if(out + 1 > eout)
25 				goto exhausted;
26 			*out++ = w;
27 			w = 0;
28 			i = 0;
29 		}
30 	}
31 exhausted:
32 	return out - start;
33 }
34 
35 int
36 enc16(char *out, int lim, uchar *in, int n)
37 {
38 	uint c;
39 	char *eout = out + lim;
40 	char *start = out;
41 
42 	while(n-- > 0){
43 		c = *in++;
44 		if(out + 2 >= eout)
45 			goto exhausted;
46 		*out++ = t16e[c>>4];
47 		*out++ = t16e[c&0xf];
48 	}
49 exhausted:
50 	*out = 0;
51 	return out - start;
52 }