aosp12/external/iproute2/lib/dnet_ntop.c

101 lines
1.7 KiB
C

#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <netinet/in.h>
#include "utils.h"
static __inline__ u_int16_t dn_ntohs(u_int16_t addr)
{
union {
u_int8_t byte[2];
u_int16_t word;
} u;
u.word = addr;
return ((u_int16_t)u.byte[0]) | (((u_int16_t)u.byte[1]) << 8);
}
static __inline__ int do_digit(char *str, u_int16_t *addr, u_int16_t scale, size_t *pos, size_t len, int *started)
{
u_int16_t tmp = *addr / scale;
if (*pos == len)
return 1;
if (((tmp) > 0) || *started || (scale == 1)) {
*str = tmp + '0';
*started = 1;
(*pos)++;
*addr -= (tmp * scale);
}
return 0;
}
static const char *dnet_ntop1(const struct dn_naddr *dna, char *str, size_t len)
{
u_int16_t addr, area;
size_t pos = 0;
int started = 0;
memcpy(&addr, dna->a_addr, sizeof(addr));
addr = dn_ntohs(addr);
area = addr >> 10;
if (dna->a_len != 2)
return NULL;
addr &= 0x03ff;
if (len == 0)
return str;
if (do_digit(str + pos, &area, 10, &pos, len, &started))
return str;
if (do_digit(str + pos, &area, 1, &pos, len, &started))
return str;
if (pos == len)
return str;
*(str + pos) = '.';
pos++;
started = 0;
if (do_digit(str + pos, &addr, 1000, &pos, len, &started))
return str;
if (do_digit(str + pos, &addr, 100, &pos, len, &started))
return str;
if (do_digit(str + pos, &addr, 10, &pos, len, &started))
return str;
if (do_digit(str + pos, &addr, 1, &pos, len, &started))
return str;
if (pos == len)
return str;
*(str + pos) = 0;
return str;
}
const char *dnet_ntop(int af, const void *addr, char *str, size_t len)
{
switch(af) {
case AF_DECnet:
errno = 0;
return dnet_ntop1((struct dn_naddr *)addr, str, len);
default:
errno = EAFNOSUPPORT;
}
return NULL;
}