res_query.c raw

   1  #define _BSD_SOURCE
   2  #include <resolv.h>
   3  #include <netdb.h>
   4  
   5  int res_query(const char *name, int class, int type, unsigned char *dest, int len)
   6  {
   7  	unsigned char q[280];
   8  	int ql = __res_mkquery(0, name, class, type, 0, 0, 0, q, sizeof q);
   9  	if (ql < 0) return ql;
  10  	int r = __res_send(q, ql, dest, len);
  11  	if (r<12) {
  12  		h_errno = TRY_AGAIN;
  13  		return -1;
  14  	}
  15  	if ((dest[3] & 15) == 3) {
  16  		h_errno = HOST_NOT_FOUND;
  17  		return -1;
  18  	}
  19  	if ((dest[3] & 15) == 0 && !dest[6] && !dest[7]) {
  20  		h_errno = NO_DATA;
  21  		return -1;
  22  	}
  23  	return r;
  24  }
  25  
  26  weak_alias(res_query, res_search);
  27