1#include <resolv.h>
2#include "libc.h"
3
4int __dn_expand(const unsigned char *base, const unsigned char *end, const unsigned char *src, char *dest, int space)
5{
6	const unsigned char *p = src;
7	char *dend, *dbegin = dest;
8	int len = -1, i, j;
9	if (p==end || space <= 0) return -1;
10	dend = dest + (space > 254 ? 254 : space);
11	/* detect reference loop using an iteration counter */
12	for (i=0; i < end-base; i+=2) {
13		/* loop invariants: p<end, dest<dend */
14		if (*p & 0xc0) {
15			if (p+1==end) return -1;
16			j = ((p[0] & 0x3f) << 8) | p[1];
17			if (len < 0) len = p+2-src;
18			if (j >= end-base) return -1;
19			p = base+j;
20		} else if (*p) {
21			if (dest != dbegin) *dest++ = '.';
22			j = *p++;
23			if (j >= end-p || j >= dend-dest) return -1;
24			while (j--) *dest++ = *p++;
25		} else {
26			*dest = 0;
27			if (len < 0) len = p+1-src;
28			return len;
29		}
30	}
31	return -1;
32}
33
34weak_alias(__dn_expand, dn_expand);
35