Loading...
#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; case 0: break; } 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 *); 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; 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; *res = h; return 0; } |