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