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#define _GNU_SOURCE
#include <sys/socket.h>
#include <netdb.h>
#include <string.h>
#include <netinet/in.h>
#include <errno.h>
#include <stdint.h>
#include "lookup.h"
int gethostbyname2_r(const char *name, int af,
struct hostent *h, char *buf, size_t buflen,
struct hostent **res, int *err)
{
struct address addrs[MAXADDRS];
char canon[256];
int i, cnt;
size_t align, need;
*res = 0;
cnt = __lookup_name(addrs, canon, name, af, AI_CANONNAME);
if (cnt<0) switch (cnt) {
case EAI_NONAME:
*err = HOST_NOT_FOUND;
return ENOENT;
case EAI_AGAIN:
*err = TRY_AGAIN;
return EAGAIN;
default:
case EAI_FAIL:
*err = NO_RECOVERY;
return EBADMSG;
case EAI_MEMORY:
case EAI_SYSTEM:
*err = NO_RECOVERY;
return errno;
}
h->h_addrtype = af;
h->h_length = af==AF_INET6 ? 16 : 4;
/* Align buffer */
align = -(uintptr_t)buf & sizeof(char *)-1;
need = 4*sizeof(char *);
need += (cnt + 1) * (sizeof(char *) + h->h_length);
need += strlen(name)+1;
need += strlen(canon)+1;
need += align;
if (need > buflen) return ERANGE;
buf += align;
h->h_aliases = (void *)buf;
buf += 3*sizeof(char *);
h->h_addr_list = (void *)buf;
buf += (cnt+1)*sizeof(char *);
for (i=0; i<cnt; i++) {
h->h_addr_list[i] = (void *)buf;
buf += h->h_length;
memcpy(h->h_addr_list[i], addrs[i].addr, h->h_length);
}
h->h_addr_list[i] = 0;
h->h_name = h->h_aliases[0] = buf;
strcpy(h->h_name, canon);
buf += strlen(h->h_name)+1;
if (strcmp(h->h_name, name)) {
h->h_aliases[1] = buf;
strcpy(h->h_aliases[1], name);
buf += strlen(h->h_aliases[1])+1;
} else h->h_aliases[1] = 0;
h->h_aliases[2] = 0;
*res = h;
return 0;
}
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