return -EINVAL;
}
-unsigned in_addr_netmask_to_prefixlen(const struct in_addr *addr) {
+unsigned char in_addr_netmask_to_prefixlen(const struct in_addr *addr) {
assert(addr);
return 32 - u32ctz(be32toh(addr->s_addr));
}
+struct in_addr* in_addr_prefixlen_to_netmask(struct in_addr *addr, unsigned char prefixlen) {
+ assert(addr);
+ assert(prefixlen <= 32);
+
+ /* Shifting beyond 32 is not defined, handle this specially. */
+ if (prefixlen == 0)
+ addr->s_addr = 0;
+ else
+ addr->s_addr = htobe32((0xffffffff << (32 - prefixlen)) & 0xffffffff);
+
+ return addr;
+}
+
int in_addr_default_prefixlen(const struct in_addr *addr, unsigned char *prefixlen) {
uint8_t msb_octet = *(uint8_t*) addr;
if (r < 0)
return r;
- assert(prefixlen > 0 && prefixlen < 32);
-
- mask->s_addr = htobe32((0xffffffff << (32 - prefixlen)) & 0xffffffff);
-
+ in_addr_prefixlen_to_netmask(mask, prefixlen);
return 0;
}