1 #include <lib9.h>
2 static char t16e[] = "0123456789ABCDEF";
3
4 int
dec16(uchar * out,int lim,char * in,int n)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
enc16(char * out,int lim,uchar * in,int n)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 }
53