1*c9945492SAndroid Build Coastguard Worker #define _GNU_SOURCE
2*c9945492SAndroid Build Coastguard Worker #include <net/if.h>
3*c9945492SAndroid Build Coastguard Worker #include <sys/socket.h>
4*c9945492SAndroid Build Coastguard Worker #include <sys/ioctl.h>
5*c9945492SAndroid Build Coastguard Worker #include <string.h>
6*c9945492SAndroid Build Coastguard Worker #include <errno.h>
7*c9945492SAndroid Build Coastguard Worker #include "syscall.h"
8*c9945492SAndroid Build Coastguard Worker
if_indextoname(unsigned index,char * name)9*c9945492SAndroid Build Coastguard Worker char *if_indextoname(unsigned index, char *name)
10*c9945492SAndroid Build Coastguard Worker {
11*c9945492SAndroid Build Coastguard Worker struct ifreq ifr;
12*c9945492SAndroid Build Coastguard Worker int fd, r;
13*c9945492SAndroid Build Coastguard Worker
14*c9945492SAndroid Build Coastguard Worker if ((fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) return 0;
15*c9945492SAndroid Build Coastguard Worker ifr.ifr_ifindex = index;
16*c9945492SAndroid Build Coastguard Worker r = ioctl(fd, SIOCGIFNAME, &ifr);
17*c9945492SAndroid Build Coastguard Worker __syscall(SYS_close, fd);
18*c9945492SAndroid Build Coastguard Worker if (r < 0) {
19*c9945492SAndroid Build Coastguard Worker if (errno == ENODEV) errno = ENXIO;
20*c9945492SAndroid Build Coastguard Worker return 0;
21*c9945492SAndroid Build Coastguard Worker }
22*c9945492SAndroid Build Coastguard Worker return strncpy(name, ifr.ifr_name, IF_NAMESIZE);
23*c9945492SAndroid Build Coastguard Worker }
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