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| | #include <resolv.h>
#include "libc.h"
int __dn_expand(const unsigned char *base, const unsigned char *end, const unsigned char *src, char *dest, int space)
{
const unsigned char *p = src;
char *dend;
int len = -1, i, j;
if (p==end || size <= 0) return -1;
dend = dest + (space > 254 ? 254 : space);
if (!*p) {
*dest = 0;
return 1;
}
/* detect reference loop using an iteration counter */
for (i=0; i < end-base; i+=2) {
if (*p & 0xc0) {
if (p+1==end) return -1;
j = ((p[0] & 0x3f) << 8) | p[1];
if (len < 0) len = p+2-src;
if (j >= end-base) return -1;
p = base+j;
} else if (*p) {
j = *p+1;
if (j>=end-p || j>dend-dest) return -1;
while (--j) *dest++ = *++p;
*dest++ = *++p ? '.' : 0;
} else {
if (len < 0) len = p+1-src;
return len;
}
}
return -1;
}
weak_alias(__dn_expand, dn_expand);
|