>>>>> On Wed, 31 May 2000 10:14:33 +0900
>>>>> [EMAIL PROTECTED] said:

itojun> isn't there some issue in getipnodebyname(), instead of getaddrinfo()?
itojun> (NOTE: I'm not really up-to-date with the current status of freebsd4
itojun> lib/libc/net)
itojun> if you can tell me repeatable example of getaddrinfo() failure, 
itojun> that would be helpful...

Yes, it's a FreeBSD specific issue.  Current getaddrinfo() is using
getipnodebyname_multi().  This was introduced by fixing search order.
There is a limitation that struct hostent cannot hold two address
families at once.  So, the host has both A RR and AAAA RR, A RR is
converted into mapped address and getaddrinfo() returns only AF_INET6.
This problem was known at introducing getipnodebyname_multi().  But,
priority of fixing search order was higher than this problem in that
time.  So, this problem is remained.
I think previous my patch is best workaround to solve this problem as
far as getaddrinfo() use getipnodeby_multi().  But, it is still
workaround.

There is one more problem.  getipnodebyname() cannot handle scope-id.
To solve above problems, we should consider that getaddrinfo() don't
use getipnodebyname().  Actually, KAME, NetBSD-current, and
OpenBSD-current don't use getipnodebyname() any more and use res_*N()
calls.  I ported it from NetBSD-current version of getaddrinfo.c and
it is running on my boxes.  And, it was committed to KAME/FreeBSD4
version of getaddrinfo.c.  But, I don't use NIS and NIS code is not
tested yet.  I attach the patch to don't use getipnodebyname_multi().

BTW, there is search order problem in current getipnodebyname(), too.
If getipnodebyname() is called with `AI_ALL|AI_V4MAPPED', this is
occur.  I attach the patch to solve this problem, too.  It also use
res_*N() calls.
Index: lib/libc/net/getaddrinfo.c
diff -u lib/libc/net/getaddrinfo.c.orig lib/libc/net/getaddrinfo.c
--- lib/libc/net/getaddrinfo.c.orig     Thu Apr 20 12:31:08 2000
+++ lib/libc/net/getaddrinfo.c  Fri May  5 22:02:17 2000
@@ -37,6 +37,9 @@
  * - Return values.  There are nonstandard return values defined and used
  *   in the source code.  This is because RFC2553 is silent about which error
  *   code must be returned for which situation.
+ * - freeaddrinfo(NULL).  RFC2553 is silent about it.  XNET 5.2 says it is
+ *   invalid.
+ *   current code - SEGV on freeaddrinfo(NULL)
  * Note:
  * - We use getipnodebyname() just for thread-safeness.  There's no intent
  *   to let it do PF_UNSPEC (actually we never pass PF_UNSPEC to
@@ -45,6 +48,41 @@
  *   when globbing NULL hostname (to loopback, or wildcard).  Is it the right
  *   thing to do?  What is the relationship with post-RFC2553 AI_ADDRCONFIG
  *   in ai_flags?
+ * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
+ *   (1) what should we do against numeric hostname (2) what should we do
+ *   against NULL hostname (3) what is AI_ADDRCONFIG itself.  AF not ready?
+ *   non-loopback address configured?  global address configured?
+ * - To avoid search order issue, we have a big amount of code duplicate
+ *   from gethnamaddr.c and some other places.  The issues that there's no
+ *   lower layer function to lookup "IPv4 or IPv6" record.  Calling
+ *   gethostbyname2 from getaddrinfo will end up in wrong search order, as
+ *   follows:
+ *     - The code makes use of following calls when asked to resolver with
+ *       ai_family  = PF_UNSPEC:
+ *             getipnodebyname(host, AF_INET6);
+ *             getipnodebyname(host, AF_INET);
+ *       This will result in the following queries if the node is configure to
+ *       prefer /etc/hosts than DNS:
+ *             lookup /etc/hosts for IPv6 address
+ *             lookup DNS for IPv6 address
+ *             lookup /etc/hosts for IPv4 address
+ *             lookup DNS for IPv4 address
+ *       which may not meet people's requirement.
+ *       The right thing to happen is to have underlying layer which does
+ *       PF_UNSPEC lookup (lookup both) and return chain of addrinfos.
+ *       This would result in a bit of code duplicate with _dns_ghbyname() and
+ *       friends.
+ */
+/*
+ * diffs with other KAME platforms:
+ * - other KAME platforms already nuked FAITH ($GAI), but as FreeBSD
+ *   4.0-RELEASE supplies it, we still have the code here.
+ * - EAI_RESNULL support
+ * - AI_ADDRCONFIG support is supplied
+ * - EDNS0 support is not available due to resolver differences
+ * - some of FreeBSD style (#define tabify and others)
+ * - AI_ADDRCONFIG is turned on by default.
+ * - classful IPv4 numeric (127.1) is allowed.
  */
 
 #include <sys/types.h>
@@ -62,6 +100,7 @@
 #include <ctype.h>
 #include <unistd.h>
 #include <stdio.h>
+#include <errno.h>
 
 #if defined(__KAME__) && defined(INET6)
 # define FAITH
@@ -108,6 +147,7 @@
 };
 
 struct explore {
+       int e_af;
        int e_socktype;
        int e_protocol;
        const char *e_protostr;
@@ -118,10 +158,21 @@
 };
 
 static const struct explore explore[] = {
-       { SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
-       { SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
-       { SOCK_RAW, ANY, NULL, 0x05 },
-       { 0, 0, NULL, 0 },
+#if 0
+       { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
+#endif
+#ifdef INET6
+       { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
+       { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
+       { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
+#endif
+       { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
+       { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
+       { PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
+       { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
+       { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
+       { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
+       { -1, 0, 0, NULL, 0 },
 };
 
 #ifdef INET6
@@ -130,12 +181,30 @@
 #define        PTON_MAX        4
 #endif
 
-extern struct  hostent * _getipnodebyname_multi __P((const char *name,
-       int af, int flags, int *errp));
+#if PACKETSZ > 1024
+#define MAXPACKET      PACKETSZ
+#else
+#define MAXPACKET      1024
+#endif
+
+typedef union {
+       HEADER hdr;
+       u_char buf[MAXPACKET];
+} querybuf;
+
+struct res_target {
+       struct res_target *next;
+       const char *name;       /* domain name */
+       int class, type;        /* class and type of query */
+       u_char *answer;         /* buffer to put answer */
+       int anslen;             /* size of answer buffer */
+       int n;                  /* result length */
+};
+
 static int str_isnumber __P((const char *));
 static int explore_fqdn __P((const struct addrinfo *, const char *,
        const char *, struct addrinfo **));
-static int explore_null __P((const struct addrinfo *, const char *,
+static int explore_null __P((const struct addrinfo *,
        const char *, struct addrinfo **));
 static int explore_numeric __P((const struct addrinfo *, const char *,
        const char *, struct addrinfo **));
@@ -148,6 +217,29 @@
 static int get_portmatch __P((const struct addrinfo *, const char *));
 static int get_port __P((struct addrinfo *, const char *, int));
 static const struct afd *find_afd __P((int));
+static int addrconfig __P((struct addrinfo *));
+#ifdef INET6
+static int ip6_str2scopeid __P((char *, struct sockaddr_in6 *));
+#endif
+
+static struct addrinfo *getanswer __P((const querybuf *, int, const char *,
+                                      int, const struct addrinfo *));
+static int _dns_getaddrinfo __P((const struct addrinfo *, const char *,
+                                struct addrinfo **));
+static struct addrinfo *_gethtent __P((FILE *fp, const char *,
+                                      const struct addrinfo *));
+static int _files_getaddrinfo __P((const struct addrinfo *, const char *,
+                                  struct addrinfo **));
+#ifdef YP
+static int _nis_getaddrinfo __P((const struct addrinfo *, const char *,
+                                struct addrinfo **));
+#endif
+
+static int res_queryN __P((const char *, struct res_target *));
+static int res_searchN __P((const char *, struct res_target *));
+static int res_querydomainN __P((const char *, const char *,
+                                struct res_target *));
+
 
 static char *ai_errlist[] = {
        "Success",
@@ -168,6 +260,32 @@
        "Unknown error",                                /* EAI_MAX        */
 };
 
+/*
+ * Select order host function.
+ */
+#define        MAXHOSTCONF     4
+
+#ifndef HOSTCONF
+#  define      HOSTCONF        "/etc/host.conf"
+#endif /* !HOSTCONF */
+
+struct _hostconf {
+       int (*byname)(const struct addrinfo *, const char *,
+                     struct addrinfo **);
+};
+
+/* default order */
+static struct _hostconf _hostconf[MAXHOSTCONF] = {
+       _dns_getaddrinfo,
+       _files_getaddrinfo,
+#ifdef ICMPNL
+       NULL,
+#endif /* ICMPNL */
+};
+
+static int     _hostconf_init_done;
+static void    _hostconf_init(void);
+
 /* XXX macros that make external reference is BAD. */
 
 #define        GET_AI(ai, afd, addr) \
@@ -178,7 +296,7 @@
                error = EAI_MEMORY; \
                goto free; \
        } \
-} while (0)
+} while (/*CONSTCOND*/0)
 
 #define        GET_PORT(ai, serv) \
 do { \
@@ -186,7 +304,7 @@
        error = get_port((ai), (serv), 0); \
        if (error != 0) \
                goto free; \
-} while (0)
+} while (/*CONSTCOND*/0)
 
 #define        GET_CANONNAME(ai, str) \
 do { \
@@ -194,19 +312,20 @@
        error = get_canonname(pai, (ai), (str)); \
        if (error != 0) \
                goto free; \
-} while (0)
+} while (/*CONSTCOND*/0)
 
 #define        ERR(err) \
 do { \
        /* external reference: error, and label bad */ \
        error = (err); \
        goto bad; \
-} while (0)
+       /*NOTREACHED*/ \
+} while (/*CONSTCOND*/0)
 
 #define        MATCH_FAMILY(x, y, w) \
-       ((x) == (y) || ((w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
+       ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
 #define        MATCH(x, y, w) \
-       ((x) == (y) || ((w) && ((x) == ANY || (y) == ANY)))
+       ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
 
 char *
 gai_strerror(ecode)
@@ -229,16 +348,17 @@
                        free(ai->ai_canonname);
                /* no need to free(ai->ai_addr) */
                free(ai);
-       } while ((ai = next) != NULL);
+               ai = next;
+       } while (ai);
 }
 
 static int
 str_isnumber(p)
        const char *p;
 {
-       char *q = (char *)p;
+       const char *q = (const char *)p;
        while (*q) {
-               if (! isdigit(*q))
+               if (!isdigit(*q))
                        return NO;
                q++;
        }
@@ -257,10 +377,9 @@
        struct addrinfo ai;
        struct addrinfo ai0;
        struct addrinfo *pai;
-       const struct afd *afd;
        const struct explore *ex;
 
-       sentinel.ai_next = NULL;
+       memset(&sentinel, 0, sizeof(sentinel));
        cur = &sentinel;
        pai = &ai;
        pai->ai_flags = 0;
@@ -300,75 +419,99 @@
                 * are meaningful combination.
                 */
                if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
-                       int matched = 0;
-
-                       for (ex = explore; ex->e_socktype; ex++) {
+                       for (ex = explore; ex->e_af >= 0; ex++) {
+                               if (pai->ai_family != ex->e_af)
+                                       continue;
                                if (ex->e_socktype == ANY)
                                        continue;
                                if (ex->e_protocol == ANY)
                                        continue;
                                if (pai->ai_socktype == ex->e_socktype
-                                && pai->ai_protocol == ex->e_protocol)
-                                       matched = 1;
-                               else
-                                       continue;
-                               if (matched == 0)
+                                && pai->ai_protocol != ex->e_protocol) {
                                        ERR(EAI_BADHINTS);
+                               }
                        }
                }
        }
 
-       /* backup original pai contents */
-       ai0 = *pai;
+       /*
+        * post-2553: AI_ALL and AI_V4MAPPED are effective only against
+        * AF_INET6 query.  They needs to be ignored if specified in other
+        * occassions.
+        */
+       switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) {
+       case AI_V4MAPPED:
+       case AI_ALL | AI_V4MAPPED:
+               if (pai->ai_family != AF_INET6)
+                       pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
+               break;
+       case AI_ALL:
+#if 1
+               /* illegal */
+               ERR(EAI_BADFLAGS);
+#else
+               pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
+#endif
+               break;
+       }
 
        /*
-        * special cases check for inet and inet6 sockets.
-        * (1) servname is disallowed for raw sockets.
-        * (2) numeric servname is disallowed if socktype/protocol is left
-        *     unspecified.
+        * check for special cases.  (1) numeric servname is disallowed if
+        * socktype/protocol are left unspecified. (2) servname is disallowed
+        * for raw and other inet{,6} sockets.
         */
        if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
-#ifdef INET6
+#ifdef PF_INET6
            || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
 #endif
            ) {
-               *pai = ai0;
+               ai0 = *pai;     /* backup *pai */
 
-               if (pai->ai_family == PF_UNSPEC)
-#ifdef INET6
+               if (pai->ai_family == PF_UNSPEC) {
+#ifdef PF_INET6
                        pai->ai_family = PF_INET6;
 #else
                        pai->ai_family = PF_INET;
 #endif
+               }
                error = get_portmatch(pai, servname);
                if (error)
                        ERR(error);
+
+               *pai = ai0;
        }
 
+       ai0 = *pai;
+
        /* NULL hostname, or numeric hostname */
-       for (afd = afdl; afd->a_af; afd++)
-      {
-       for (ex = explore; ex->e_socktype; ex++) {
+       for (ex = explore; ex->e_af >= 0; ex++) {
                *pai = ai0;
 
-               if (!MATCH_FAMILY(pai->ai_family, afd->a_af, WILD_AF(ex)))
+               /* PF_UNSPEC entries are prepared for DNS queries only */
+               if (ex->e_af == PF_UNSPEC)
                        continue;
-               if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex)))
+
+               if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
+                       continue;
+               if (!MATCH(pai->ai_socktype, ex->e_socktype,
+                          WILD_SOCKTYPE(ex)))
                        continue;
-               if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex)))
+               if (!MATCH(pai->ai_protocol, ex->e_protocol,
+                          WILD_PROTOCOL(ex)))
                        continue;
 
                if (pai->ai_family == PF_UNSPEC)
-                       pai->ai_family = afd->a_af;
+                       pai->ai_family = ex->e_af;
                if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
                        pai->ai_socktype = ex->e_socktype;
                if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
                        pai->ai_protocol = ex->e_protocol;
 
                if (hostname == NULL)
-                       error = explore_null(pai, hostname, servname, &cur->ai_next);
+                       error = explore_null(pai, servname, &cur->ai_next);
                else
-                       error = explore_numeric_scope(pai, hostname, servname, 
&cur->ai_next);
+                       error = explore_numeric_scope(pai, hostname, servname,
+                                                     &cur->ai_next);
 
                if (error)
                        goto free;
@@ -376,7 +519,6 @@
                while (cur && cur->ai_next)
                        cur = cur->ai_next;
        }
-      }
 
        /*
         * XXX
@@ -391,50 +533,143 @@
        if (hostname == NULL)
                ERR(EAI_NONAME);
 
-       /* hostname as alphabetical name. */
-       {
-               for (ex = explore; ex->e_socktype; ex++) {
-                       *pai = ai0;
-
-                       if (!MATCH(pai->ai_socktype, ex->e_socktype,
-                                       WILD_SOCKTYPE(ex))) {
-                               continue;
-                       }
-                       if (!MATCH(pai->ai_protocol, ex->e_protocol,
-                                       WILD_PROTOCOL(ex))) {
-                               continue;
-                       }
+#if 1
+       /* XXX: temporarily, behave as if AI_ADDRCONFIG is specified */
+       pai->ai_flags |= AI_ADDRCONFIG;
+#endif
+       if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0))
+               ERR(EAI_FAIL);
 
-                       if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
-                               pai->ai_socktype = ex->e_socktype;
-                       if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
-                               pai->ai_protocol = ex->e_protocol;
+       /*
+        * hostname as alphabetical name.
+        * we would like to prefer AF_INET6 than AF_INET, so we'll make a
+        * outer loop by AFs.
+        */
+       for (ex = explore; ex->e_af >= 0; ex++) {
+               *pai = ai0;
 
-                       error = explore_fqdn(pai, hostname, servname,
-                               &cur->ai_next);
+               /* require exact match for family field */
+               if (pai->ai_family != ex->e_af)
+                       continue;
 
-                       while (cur && cur->ai_next)
-                               cur = cur->ai_next;
+               if (!MATCH(pai->ai_socktype, ex->e_socktype,
+                          WILD_SOCKTYPE(ex))) {
+                       continue;
                }
+               if (!MATCH(pai->ai_protocol, ex->e_protocol,
+                          WILD_PROTOCOL(ex))) {
+                       continue;
+               }
+
+               if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
+                       pai->ai_socktype = ex->e_socktype;
+               if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
+                       pai->ai_protocol = ex->e_protocol;
+
+               error = explore_fqdn(pai, hostname, servname, &cur->ai_next);
+
+               while (cur && cur->ai_next)
+                       cur = cur->ai_next;
        }
 
-       /* XXX: if any addrinfo found, SUCCESS return even if (error != 0) */
-       if (sentinel.ai_next) {
+       /* XXX */
+       if (sentinel.ai_next)
+               error = 0;
+
+       if (error)
+               goto free;
+       if (error == 0) {
+               if (sentinel.ai_next) {
  good:
-               *res = sentinel.ai_next;
-               return SUCCESS;
+                       *res = sentinel.ai_next;
+                       return SUCCESS;
+               } else
+                       error = EAI_FAIL;
        }
-       /* else, failed */
  free:
  bad:
-       if (error == 0)
-               error = EAI_FAIL;
        if (sentinel.ai_next)
                freeaddrinfo(sentinel.ai_next);
        *res = NULL;
        return error;
 }
 
+static char *
+_hgetword(char **pp)
+{
+       char c, *p, *ret;
+       const char *sp;
+       static const char sep[] = "# \t\n";
+
+       ret = NULL;
+       for (p = *pp; (c = *p) != '\0'; p++) {
+               for (sp = sep; *sp != '\0'; sp++) {
+                       if (c == *sp)
+                               break;
+               }
+               if (c == '#')
+                       p[1] = '\0';    /* ignore rest of line */
+               if (ret == NULL) {
+                       if (*sp == '\0')
+                               ret = p;
+               } else {
+                       if (*sp != '\0') {
+                               *p++ = '\0';
+                               break;
+                       }
+               }
+       }
+       *pp = p;
+       if (ret == NULL || *ret == '\0')
+               return NULL;
+       return ret;
+}
+
+/*
+ * Initialize hostconf structure.
+ */
+
+static void
+_hostconf_init(void)
+{
+       FILE *fp;
+       int n;
+       char *p, *line;
+       char buf[BUFSIZ];
+
+       _hostconf_init_done = 1;
+       n = 0;
+       p = HOSTCONF;
+       if ((fp = fopen(p, "r")) == NULL)
+               return;
+       while (n < MAXHOSTCONF && fgets(buf, sizeof(buf), fp)) {
+               line = buf;
+               if ((p = _hgetword(&line)) == NULL)
+                       continue;
+               do {
+                       if (strcmp(p, "hosts") == 0
+                       ||  strcmp(p, "local") == 0
+                       ||  strcmp(p, "file") == 0
+                       ||  strcmp(p, "files") == 0)
+                               _hostconf[n++].byname = _files_getaddrinfo;
+                       else if (strcmp(p, "dns") == 0
+                            ||  strcmp(p, "bind") == 0)
+                               _hostconf[n++].byname = _dns_getaddrinfo;
+#ifdef YP
+                       else if (strcmp(p, "nis") == 0)
+                               _hostconf[n++].byname = _nis_getaddrinfo;
+#endif
+               } while ((p = _hgetword(&line)) != NULL);
+       }
+       fclose(fp);
+       if (n < 0) {
+               /* no keyword found. do not change default configuration */
+               return;
+       }
+       for (; n < MAXHOSTCONF; n++)
+               _hostconf[n].byname = NULL;
+}
+
 /*
  * FQDN hostname, DNS lookup
  */
@@ -445,18 +680,12 @@
        const char *servname;
        struct addrinfo **res;
 {
-       struct hostent *hp;
-       int h_error;
-       int af;
-       char *ap;
-       struct addrinfo sentinel, *cur;
-       int i;
-       const struct afd *afd;
-       int error;
+       struct addrinfo *result;
+       struct addrinfo *cur;
+       int error = 0, i;
 
+       result = NULL;
        *res = NULL;
-       sentinel.ai_next = NULL;
-       cur = &sentinel;
 
        /*
         * if the servname does not match socktype/protocol, ignore it.
@@ -464,67 +693,26 @@
        if (get_portmatch(pai, servname) != 0)
                return 0;
 
-       hp = _getipnodebyname_multi(hostname, pai->ai_family, AI_ADDRCONFIG,
-                                      &h_error);
-       if (hp == NULL) {
-               switch (h_error) {
-               case HOST_NOT_FOUND:
-               case NO_DATA:
-                       error = EAI_NODATA;
-                       break;
-               case TRY_AGAIN:
-                       error = EAI_AGAIN;
-                       break;
-               case NO_RECOVERY:
-               case NETDB_INTERNAL:
-               default:
-                       error = EAI_FAIL;
-                       break;
-               }
-       } else if ((hp->h_name == NULL) || (hp->h_name[0] == 0)
-                       || (hp->h_addr_list[0] == NULL)) {
-               freehostent(hp);
-               hp = NULL;
-               error = EAI_FAIL;
-       }
-
-       if (hp == NULL)
-               goto free;
-
-       for (i = 0; hp->h_addr_list[i] != NULL; i++) {
-               af = hp->h_addrtype;
-               ap = hp->h_addr_list[i];
+       if (!_hostconf_init_done)
+               _hostconf_init();
 
-               if (pai->ai_family != AF_UNSPEC && af != pai->ai_family)
+       for (i = 0; i < MAXHOSTCONF; i++) {
+               if (!_hostconf[i].byname)
                        continue;
-
-               afd = find_afd(af);
-               if (afd == NULL)
+               error = (*_hostconf[i].byname)(pai, hostname, &result);
+               if (error != 0)
                        continue;
-
-               GET_AI(cur->ai_next, afd, ap);
-               GET_PORT(cur->ai_next, servname);
-               if ((pai->ai_flags & AI_CANONNAME) != 0) {
-                       /*
-                        * RFC2553 says that ai_canonname will be set only for
-                        * the first element.  we do it for all the elements,
-                        * just for convenience.
-                        */
-                       GET_CANONNAME(cur->ai_next, hp->h_name);
+               for (cur = result; cur; cur = cur->ai_next) {
+                       GET_PORT(cur, servname);
+                       /* canonname should be filled already */
                }
-
-               while (cur && cur->ai_next)
-                       cur = cur->ai_next;
+               *res = result;
+               return 0;
        }
 
-       *res = sentinel.ai_next;
-       return 0;
-
 free:
-       if (hp)
-               freehostent(hp);
-       if (sentinel.ai_next)
-               freeaddrinfo(sentinel.ai_next);
+       if (result)
+               freeaddrinfo(result);
        return error;
 }
 
@@ -534,9 +722,8 @@
  * non-passive socket -> localhost (127.0.0.1 or ::1)
  */
 static int
-explore_null(pai, hostname, servname, res)
+explore_null(pai, servname, res)
        const struct addrinfo *pai;
-       const char *hostname;
        const char *servname;
        struct addrinfo **res;
 {
@@ -555,23 +742,36 @@
         * XXX errno?
         */
        s = socket(pai->ai_family, SOCK_DGRAM, 0);
-       if (s < 0)
+       if (s < 0) {
+               if (errno != EMFILE)
+                       return 0;
+       } else
+               _close(s);
+
+       /*
+        * if the servname does not match socktype/protocol, ignore it.
+        */
+       if (get_portmatch(pai, servname) != 0)
                return 0;
-       _close(s);
+
        afd = find_afd(pai->ai_family);
        if (afd == NULL)
                return 0;
 
-       GET_AI(cur->ai_next, afd,
-              (pai->ai_flags & AI_PASSIVE) ? afd->a_addrany : afd->a_loopback
-              );
-       /* xxx meaningless?
-        * GET_CANONNAME(cur->ai_next, "anyaddr");
-        * or
-        * GET_CANONNAME(cur->ai_next, "localhost");
-        */
-       /* if the servname does not match socktype/protocol, ignored */
-       GET_PORT(cur->ai_next, servname);
+       if (pai->ai_flags & AI_PASSIVE) {
+               GET_AI(cur->ai_next, afd, afd->a_addrany);
+               /* xxx meaningless?
+                * GET_CANONNAME(cur->ai_next, "anyaddr");
+                */
+               GET_PORT(cur->ai_next, servname);
+       } else {
+               GET_AI(cur->ai_next, afd, afd->a_loopback);
+               /* xxx meaningless?
+                * GET_CANONNAME(cur->ai_next, "localhost");
+                */
+               GET_PORT(cur->ai_next, servname);
+       }
+       cur = cur->ai_next;
 
        *res = sentinel.ai_next;
        return 0;
@@ -597,7 +797,6 @@
        struct addrinfo sentinel;
        int error;
        char pton[PTON_MAX];
-       int flags;
 
        *res = NULL;
        sentinel.ai_next = NULL;
@@ -612,7 +811,6 @@
        afd = find_afd(pai->ai_family);
        if (afd == NULL)
                return 0;
-       flags = pai->ai_flags;
 
        if ((afd->a_af == AF_INET
             ? inet_aton(hostname, (struct in_addr *)pton)
@@ -647,17 +845,14 @@
        const char *servname;
        struct addrinfo **res;
 {
-#ifndef SCOPE_DELIMITER
+#if !defined(SCOPE_DELIMITER) || !defined(INET6)
        return explore_numeric(pai, hostname, servname, res);
 #else
        const struct afd *afd;
        struct addrinfo *cur;
        int error;
-       char *cp, *hostname2 = NULL;
-       int scope;
-#ifdef INET6
+       char *cp, *hostname2 = NULL, *scope, *addr;
        struct sockaddr_in6 *sin6;
-#endif
 
        /*
         * if the servname does not match socktype/protocol, ignore it.
@@ -683,37 +878,25 @@
                return EAI_MEMORY;
        /* terminate at the delimiter */
        hostname2[cp - hostname] = '\0';
+       addr = hostname2;
+       scope = cp + 1;
 
-       cp++;
-       switch (pai->ai_family) {
-#ifdef INET6
-       case AF_INET6:
-               scope = if_nametoindex(cp);
-               if (scope == 0) {
-                       error = EAI_SYSTEM;
-                       goto free;
-               }
-               break;
-#endif
-       }
-
-       error = explore_numeric(pai, hostname2, servname, res);
+       error = explore_numeric(pai, addr, servname, res);
        if (error == 0) {
+               int scopeid;
+
                for (cur = *res; cur; cur = cur->ai_next) {
-#ifdef INET6
                        if (cur->ai_family != AF_INET6)
                                continue;
-                       sin6 = (struct sockaddr_in6 *)cur->ai_addr;
-                       if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) ||
-                           IN6_IS_ADDR_MC_LINKLOCAL(&sin6->sin6_addr))
-                               sin6->sin6_scope_id = scope;
-#endif
+                       sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
+                       if ((scopeid = ip6_str2scopeid(scope, sin6)) == -1) {
+                               free(hostname2);
+                               return(EAI_NONAME); /* XXX: is return OK? */
+                       }
+                       sin6->sin6_scope_id = scopeid;
                }
        }
 
-#ifdef INET6
-free:
-#endif
        free(hostname2);
 
        return error;
@@ -791,8 +974,8 @@
                return NULL;
 
        memcpy(ai, pai, sizeof(struct addrinfo));
-       ai->ai_addr = (struct sockaddr *)(ai + 1);
-       memset(ai->ai_addr, 0, afd->a_socklen);
+       ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
+       memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
        ai->ai_addr->sa_len = afd->a_socklen;
        ai->ai_addrlen = afd->a_socklen;
        ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
@@ -812,7 +995,9 @@
        const struct addrinfo *ai;
        const char *servname;
 {
+
        /* get_port does not touch first argument. when matchonly == 1. */
+       /* LINTED const cast */
        return get_port((struct addrinfo *)ai, servname, 1);
 }
 
@@ -829,12 +1014,15 @@
 
        if (servname == NULL)
                return 0;
-       if (ai->ai_family != AF_INET
-#ifdef INET6
-           && ai->ai_family != AF_INET6
+       switch (ai->ai_family) {
+       case AF_INET:
+#ifdef AF_INET6
+       case AF_INET6:
 #endif
-           )
+               break;
+       default:
                return 0;
+       }
 
        switch (ai->ai_socktype) {
        case SOCK_RAW:
@@ -877,11 +1065,13 @@
        if (!matchonly) {
                switch (ai->ai_family) {
                case AF_INET:
-                       ((struct sockaddr_in *)ai->ai_addr)->sin_port = port;
+                       ((struct sockaddr_in *)(void *)
+                           ai->ai_addr)->sin_port = port;
                        break;
 #ifdef INET6
                case AF_INET6:
-                       ((struct sockaddr_in6 *)ai->ai_addr)->sin6_port = port;
+                       ((struct sockaddr_in6 *)(void *)
+                           ai->ai_addr)->sin6_port = port;
                        break;
 #endif
                }
@@ -903,4 +1093,844 @@
                        return afd;
        }
        return NULL;
+}
+
+/*
+ * post-2553: AI_ADDRCONFIG check.  if we use getipnodeby* as backend, backend
+ * will take care of it.
+ * the semantics of AI_ADDRCONFIG is not defined well.  we are not sure
+ * if the code is right or not.
+ *
+ * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with
+ * _dns_getaddrinfo.
+ */
+static int
+addrconfig(pai)
+       struct addrinfo *pai;
+{
+       int s, af;
+
+       /*
+        * TODO:
+        * Note that implementation dependent test for address
+        * configuration should be done everytime called
+        * (or apropriate interval),
+        * because addresses will be dynamically assigned or deleted.
+        */
+       af = pai->ai_family;
+       if (af == AF_UNSPEC) {
+               if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
+                       af = AF_INET;
+               else {
+                       close(s);
+                       if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
+                               af = AF_INET6;
+                       else
+                               close(s);
+               }
+
+       }
+       if (af != AF_UNSPEC) {
+               if ((s = socket(af, SOCK_DGRAM, 0)) < 0)
+                       return 0;
+               close(s);
+       }
+       pai->ai_family = af;
+       return 1;
+}
+
+#ifdef INET6
+/* convert a string to a scope identifier. XXX: IPv6 specific */
+static int
+ip6_str2scopeid(scope, sin6)
+       char *scope;
+       struct sockaddr_in6 *sin6;
+{
+       int scopeid;
+       struct in6_addr *a6 = &sin6->sin6_addr;
+       char *ep;
+
+       if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
+               /*
+                * We currently assume a one-to-one mapping between links
+                * and interfaces, so we simply use interface indices for
+                * like-local scopes.
+                */
+               scopeid = if_nametoindex(scope);
+               if (scopeid == 0)
+                       goto trynumeric;
+               return(scopeid);
+       }
+
+       /* still unclear about literal, allow numeric only - placeholder */
+       if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
+               goto trynumeric;
+       if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
+               goto trynumeric;
+       else
+               goto trynumeric;        /* global */
+
+       /* try to convert to a numeric id as a last resort */
+  trynumeric:
+       scopeid = (int)strtoul(scope, &ep, 10);
+       if (*ep == '\0')
+               return scopeid;
+       else
+               return -1;
+}
+#endif
+
+#ifdef DEBUG
+static const char AskedForGot[] =
+       "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
+#endif
+
+static struct addrinfo *
+getanswer(answer, anslen, qname, qtype, pai)
+       const querybuf *answer;
+       int anslen;
+       const char *qname;
+       int qtype;
+       const struct addrinfo *pai;
+{
+       struct addrinfo sentinel, *cur;
+       struct addrinfo ai;
+       const struct afd *afd;
+       char *canonname;
+       const HEADER *hp;
+       const u_char *cp;
+       int n;
+       const u_char *eom;
+       char *bp;
+       int type, class, buflen, ancount, qdcount;
+       int haveanswer, had_error;
+       char tbuf[MAXDNAME];
+       int (*name_ok) __P((const char *));
+       char hostbuf[8*1024];
+
+       memset(&sentinel, 0, sizeof(sentinel));
+       cur = &sentinel;
+
+       canonname = NULL;
+       eom = answer->buf + anslen;
+       switch (qtype) {
+       case T_A:
+       case T_AAAA:
+       case T_ANY:     /*use T_ANY only for T_A/T_AAAA lookup*/
+               name_ok = res_hnok;
+               break;
+       default:
+               return (NULL);  /* XXX should be abort(); */
+       }
+       /*
+        * find first satisfactory answer
+        */
+       hp = &answer->hdr;
+       ancount = ntohs(hp->ancount);
+       qdcount = ntohs(hp->qdcount);
+       bp = hostbuf;
+       buflen = sizeof hostbuf;
+       cp = answer->buf + HFIXEDSZ;
+       if (qdcount != 1) {
+               h_errno = NO_RECOVERY;
+               return (NULL);
+       }
+       n = dn_expand(answer->buf, eom, cp, bp, buflen);
+       if ((n < 0) || !(*name_ok)(bp)) {
+               h_errno = NO_RECOVERY;
+               return (NULL);
+       }
+       cp += n + QFIXEDSZ;
+       if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
+               /* res_send() has already verified that the query name is the
+                * same as the one we sent; this just gets the expanded name
+                * (i.e., with the succeeding search-domain tacked on).
+                */
+               n = strlen(bp) + 1;             /* for the \0 */
+               if (n >= MAXHOSTNAMELEN) {
+                       h_errno = NO_RECOVERY;
+                       return (NULL);
+               }
+               canonname = bp;
+               bp += n;
+               buflen -= n;
+               /* The qname can be abbreviated, but h_name is now absolute. */
+               qname = canonname;
+       }
+       haveanswer = 0;
+       had_error = 0;
+       while (ancount-- > 0 && cp < eom && !had_error) {
+               n = dn_expand(answer->buf, eom, cp, bp, buflen);
+               if ((n < 0) || !(*name_ok)(bp)) {
+                       had_error++;
+                       continue;
+               }
+               cp += n;                        /* name */
+               type = _getshort(cp);
+               cp += INT16SZ;                  /* type */
+               class = _getshort(cp);
+               cp += INT16SZ + INT32SZ;        /* class, TTL */
+               n = _getshort(cp);
+               cp += INT16SZ;                  /* len */
+               if (class != C_IN) {
+                       /* XXX - debug? syslog? */
+                       cp += n;
+                       continue;               /* XXX - had_error++ ? */
+               }
+               if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
+                   type == T_CNAME) {
+                       n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
+                       if ((n < 0) || !(*name_ok)(tbuf)) {
+                               had_error++;
+                               continue;
+                       }
+                       cp += n;
+                       /* Get canonical name. */
+                       n = strlen(tbuf) + 1;   /* for the \0 */
+                       if (n > buflen || n >= MAXHOSTNAMELEN) {
+                               had_error++;
+                               continue;
+                       }
+                       strcpy(bp, tbuf);
+                       canonname = bp;
+                       bp += n;
+                       buflen -= n;
+                       continue;
+               }
+               if (qtype == T_ANY) {
+                       if (!(type == T_A || type == T_AAAA)) {
+                               cp += n;
+                               continue;
+                       }
+               } else if (type != qtype) {
+#ifdef DEBUG
+                       if (type != T_KEY && type != T_SIG)
+                               syslog(LOG_NOTICE|LOG_AUTH,
+              "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
+                                      qname, p_class(C_IN), p_type(qtype),
+                                      p_type(type));
+#endif
+                       cp += n;
+                       continue;               /* XXX - had_error++ ? */
+               }
+               switch (type) {
+               case T_A:
+               case T_AAAA:
+                       if (strcasecmp(canonname, bp) != 0) {
+#ifdef DEBUG
+                               syslog(LOG_NOTICE|LOG_AUTH,
+                                      AskedForGot, canonname, bp);
+#endif
+                               cp += n;
+                               continue;       /* XXX - had_error++ ? */
+                       }
+                       if (type == T_A && n != INADDRSZ) {
+                               cp += n;
+                               continue;
+                       }
+                       if (type == T_AAAA && n != IN6ADDRSZ) {
+                               cp += n;
+                               continue;
+                       }
+#ifdef FILTER_V4MAPPED
+                       if (type == T_AAAA) {
+                               struct in6_addr in6;
+                               memcpy(&in6, cp, sizeof(in6));
+                               if (IN6_IS_ADDR_V4MAPPED(&in6)) {
+                                       cp += n;
+                                       continue;
+                               }
+                       }
+#endif
+                       if (!haveanswer) {
+                               int nn;
+
+                               canonname = bp;
+                               nn = strlen(bp) + 1;    /* for the \0 */
+                               bp += nn;
+                               buflen -= nn;
+                       }
+
+                       /* don't overwrite pai */
+                       ai = *pai;
+                       ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
+                       afd = find_afd(ai.ai_family);
+                       if (afd == NULL) {
+                               cp += n;
+                               continue;
+                       }
+                       cur->ai_next = get_ai(&ai, afd, (const char *)cp);
+                       if (cur->ai_next == NULL)
+                               had_error++;
+                       while (cur && cur->ai_next)
+                               cur = cur->ai_next;
+                       cp += n;
+                       break;
+               default:
+                       abort();
+               }
+               if (!had_error)
+                       haveanswer++;
+       }
+       if (haveanswer) {
+               if (!canonname)
+                       (void)get_canonname(pai, sentinel.ai_next, qname);
+               else
+                       (void)get_canonname(pai, sentinel.ai_next, canonname);
+               h_errno = NETDB_SUCCESS;
+               return sentinel.ai_next;
+       }
+
+       h_errno = NO_RECOVERY;
+       return NULL;
+}
+
+/*ARGSUSED*/
+static int
+_dns_getaddrinfo(pai, hostname, res)
+       const struct addrinfo *pai;
+       const char *hostname;
+       struct addrinfo **res;
+{
+       struct addrinfo *ai;
+       querybuf buf, buf2;
+       const char *name;
+       struct addrinfo sentinel, *cur;
+       struct res_target q, q2;
+
+       memset(&q, 0, sizeof(q2));
+       memset(&q2, 0, sizeof(q2));
+       memset(&sentinel, 0, sizeof(sentinel));
+       cur = &sentinel;
+
+       switch (pai->ai_family) {
+       case AF_UNSPEC:
+               /* prefer IPv6 */
+               q.class = C_IN;
+               q.type = T_AAAA;
+               q.answer = buf.buf;
+               q.anslen = sizeof(buf);
+               q.next = &q2;
+               q2.class = C_IN;
+               q2.type = T_A;
+               q2.answer = buf2.buf;
+               q2.anslen = sizeof(buf2);
+               break;
+       case AF_INET:
+               q.class = C_IN;
+               q.type = T_A;
+               q.answer = buf.buf;
+               q.anslen = sizeof(buf);
+               break;
+       case AF_INET6:
+               q.class = C_IN;
+               q.type = T_AAAA;
+               q.answer = buf.buf;
+               q.anslen = sizeof(buf);
+               break;
+       default:
+               return EAI_FAIL;
+       }
+       if (res_searchN(hostname, &q) < 0)
+               return EAI_NODATA;
+       ai = getanswer(&buf, q.n, q.name, q.type, pai);
+       if (ai) {
+               cur->ai_next = ai;
+               while (cur && cur->ai_next)
+                       cur = cur->ai_next;
+       }
+       if (q.next) {
+               ai = getanswer(&buf2, q2.n, q2.name, q2.type, pai);
+               if (ai)
+                       cur->ai_next = ai;
+       }
+       if (sentinel.ai_next == NULL)
+               switch (h_errno) {
+               case HOST_NOT_FOUND:
+                       return EAI_NODATA;
+               case TRY_AGAIN:
+                       return EAI_AGAIN;
+               default:
+                       return EAI_FAIL;
+               }
+       *res = sentinel.ai_next;
+       return 0;
+}
+
+static struct addrinfo *
+_gethtent(hostf, name, pai)
+       FILE *hostf;
+       const char *name;
+       const struct addrinfo *pai;
+{
+       char *p;
+       char *cp, *tname, *cname;
+       struct addrinfo hints, *res0, *res;
+       int error;
+       const char *addr;
+       char hostbuf[8*1024];
+
+ again:
+       if (!(p = fgets(hostbuf, sizeof hostbuf, hostf)))
+               return (NULL);
+       if (*p == '#')
+               goto again;
+       if (!(cp = strpbrk(p, "#\n")))
+               goto again;
+       *cp = '\0';
+       if (!(cp = strpbrk(p, " \t")))
+               goto again;
+       *cp++ = '\0';
+       addr = p;
+       cname = NULL;
+       /* if this is not something we're looking for, skip it. */
+       while (cp && *cp) {
+               if (*cp == ' ' || *cp == '\t') {
+                       cp++;
+                       continue;
+               }
+               tname = cp;
+               if (cname == NULL)
+                       cname = cp;
+               if ((cp = strpbrk(cp, " \t")) != NULL)
+                       *cp++ = '\0';
+               if (strcasecmp(name, tname) == 0)
+                       goto found;
+       }
+       goto again;
+
+found:
+       hints = *pai;
+       hints.ai_flags = AI_NUMERICHOST;
+       error = getaddrinfo(addr, NULL, &hints, &res0);
+       if (error)
+               goto again;
+#ifdef FILTER_V4MAPPED
+       /* XXX should check all items in the chain */
+       if (res0->ai_family == AF_INET6 &&
+           IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) {
+               freeaddrinfo(res0);
+               goto again;
+       }
+#endif
+       for (res = res0; res; res = res->ai_next) {
+               /* cover it up */
+               res->ai_flags = pai->ai_flags;
+
+               if (pai->ai_flags & AI_CANONNAME) {
+                       if (get_canonname(pai, res, cname) != 0) {
+                               freeaddrinfo(res0);
+                               goto again;
+                       }
+               }
+       }
+       return res0;
+}
+
+/*ARGSUSED*/
+static int
+_files_getaddrinfo(pai, hostname, res)
+       const struct addrinfo *pai;
+       const char *hostname;
+       struct addrinfo **res;
+{
+       FILE *hostf;
+       struct addrinfo sentinel, *cur;
+       struct addrinfo *p;
+
+       sentinel.ai_next = NULL;
+       cur = &sentinel;
+
+       if ((hostf = fopen(_PATH_HOSTS, "r")) == NULL)
+               return EAI_FAIL;
+       while ((p = _gethtent(hostf, hostname, pai)) != NULL) {
+               cur->ai_next = p;
+               while (cur && cur->ai_next)
+                       cur = cur->ai_next;
+       }
+       fclose(hostf);
+
+       if (!sentinel.ai_next)
+               return EAI_NODATA;
+
+       *res = sentinel.ai_next;
+       return 0;
+}
+
+#ifdef YP
+/*ARGSUSED*/
+static int
+_nis_getaddrinfo(pai, hostname, res)
+       const struct addrinfo *pai;
+       const char *hostname;
+       struct addrinfo **res;
+{
+       struct hostent *hp;
+       int h_error;
+       int af;
+       char *ap;
+       struct addrinfo sentinel, *cur;
+       int i;
+       const struct afd *afd;
+       int error;
+
+       sentinel.ai_next = NULL;
+       cur = &sentinel;
+
+       af = (pai->ai_family == AF_UNSPEC) ? AF_INET : pai->ai_family;
+       if (af != AF_INET)
+               return (EAI_ADDRFAMILY);
+
+       if ((hp = _gethostbynisname(hostname, af)) == NULL) {
+               switch (errno) {
+               /* XXX: should be filled in */
+               default:
+                       error = EAI_FAIL;
+                       break;
+               }
+       } else if (hp->h_name == NULL ||
+                  hp->h_name[0] == 0 || hp->h_addr_list[0] == NULL) {
+               hp = NULL;
+               error = EAI_FAIL;
+       }
+
+       if (hp == NULL)
+               return error;
+
+       for (i = 0; hp->h_addr_list[i] != NULL; i++) {
+               af = hp->h_addrtype;
+               ap = hp->h_addr_list[i];
+
+               if (af != pai->ai_family)
+                       continue;
+
+               afd = find_afd(af);
+               if (afd == NULL)
+                       continue;
+
+               GET_AI(cur->ai_next, afd, ap);
+               if ((pai->ai_flags & AI_CANONNAME) != 0) {
+                       /*
+                        * RFC2553 says that ai_canonname will be set only for
+                        * the first element.  we do it for all the elements,
+                        * just for convenience.
+                        */
+                       GET_CANONNAME(cur->ai_next, hp->h_name);
+               }
+
+               while (cur && cur->ai_next)
+                       cur = cur->ai_next;
+       }
+
+       *res = sentinel.ai_next;
+       return 0;
+
+free:
+       if (sentinel.ai_next)
+               freeaddrinfo(sentinel.ai_next);
+       return error;
+}
+#endif
+
+/* resolver logic */
+
+extern const char *__hostalias __P((const char *));
+extern int h_errno;
+
+/*
+ * Formulate a normal query, send, and await answer.
+ * Returned answer is placed in supplied buffer "answer".
+ * Perform preliminary check of answer, returning success only
+ * if no error is indicated and the answer count is nonzero.
+ * Return the size of the response on success, -1 on error.
+ * Error number is left in h_errno.
+ *
+ * Caller must parse answer and determine whether it answers the question.
+ */
+static int
+res_queryN(name, target)
+       const char *name;       /* domain name */
+       struct res_target *target;
+{
+       u_char buf[MAXPACKET];
+       HEADER *hp;
+       int n;
+       struct res_target *t;
+       int rcode;
+       int ancount;
+
+       rcode = NOERROR;
+       ancount = 0;
+
+       if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
+               h_errno = NETDB_INTERNAL;
+               return (-1);
+       }
+
+       for (t = target; t; t = t->next) {
+               int class, type;
+               u_char *answer;
+               int anslen;
+
+               hp = (HEADER *)(void *)t->answer;
+               hp->rcode = NOERROR;    /* default */
+
+               /* make it easier... */
+               class = t->class;
+               type = t->type;
+               answer = t->answer;
+               anslen = t->anslen;
+#ifdef DEBUG
+               if (_res.options & RES_DEBUG)
+                       printf(";; res_query(%s, %d, %d)\n", name, class, type);
+#endif
+
+               n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL,
+                   buf, sizeof(buf));
+               if (n <= 0) {
+#ifdef DEBUG
+                       if (_res.options & RES_DEBUG)
+                               printf(";; res_query: mkquery failed\n");
+#endif
+                       h_errno = NO_RECOVERY;
+                       return (n);
+               }
+               n = res_send(buf, n, answer, anslen);
+#if 0
+               if (n < 0) {
+#ifdef DEBUG
+                       if (_res.options & RES_DEBUG)
+                               printf(";; res_query: send error\n");
+#endif
+                       h_errno = TRY_AGAIN;
+                       return (n);
+               }
+#endif
+
+               if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
+                       rcode = hp->rcode;      /* record most recent error */
+#ifdef DEBUG
+                       if (_res.options & RES_DEBUG)
+                               printf(";; rcode = %d, ancount=%d\n", hp->rcode,
+                                   ntohs(hp->ancount));
+#endif
+                       continue;
+               }
+
+               ancount += ntohs(hp->ancount);
+
+               t->n = n;
+       }
+
+       if (ancount == 0) {
+               switch (rcode) {
+               case NXDOMAIN:
+                       h_errno = HOST_NOT_FOUND;
+                       break;
+               case SERVFAIL:
+                       h_errno = TRY_AGAIN;
+                       break;
+               case NOERROR:
+                       h_errno = NO_DATA;
+                       break;
+               case FORMERR:
+               case NOTIMP:
+               case REFUSED:
+               default:
+                       h_errno = NO_RECOVERY;
+                       break;
+               }
+               return (-1);
+       }
+       return (ancount);
+}
+
+/*
+ * Formulate a normal query, send, and retrieve answer in supplied buffer.
+ * Return the size of the response on success, -1 on error.
+ * If enabled, implement search rules until answer or unrecoverable failure
+ * is detected.  Error code, if any, is left in h_errno.
+ */
+static int
+res_searchN(name, target)
+       const char *name;       /* domain name */
+       struct res_target *target;
+{
+       const char *cp, * const *domain;
+       HEADER *hp = (HEADER *)(void *)target->answer;  /*XXX*/
+       u_int dots;
+       int trailing_dot, ret, saved_herrno;
+       int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
+
+       if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
+               h_errno = NETDB_INTERNAL;
+               return (-1);
+       }
+
+       errno = 0;
+       h_errno = HOST_NOT_FOUND;       /* default, if we never query */
+       dots = 0;
+       for (cp = name; *cp; cp++)
+               dots += (*cp == '.');
+       trailing_dot = 0;
+       if (cp > name && *--cp == '.')
+               trailing_dot++;
+
+       /*
+        * if there aren't any dots, it could be a user-level alias
+        */
+       if (!dots && (cp = __hostalias(name)) != NULL)
+               return (res_queryN(cp, target));
+
+       /*
+        * If there are dots in the name already, let's just give it a try
+        * 'as is'.  The threshold can be set with the "ndots" option.
+        */
+       saved_herrno = -1;
+       if (dots >= _res.ndots) {
+               ret = res_querydomainN(name, NULL, target);
+               if (ret > 0)
+                       return (ret);
+               saved_herrno = h_errno;
+               tried_as_is++;
+       }
+
+       /*
+        * We do at least one level of search if
+        *      - there is no dot and RES_DEFNAME is set, or
+        *      - there is at least one dot, there is no trailing dot,
+        *        and RES_DNSRCH is set.
+        */
+       if ((!dots && (_res.options & RES_DEFNAMES)) ||
+           (dots && !trailing_dot && (_res.options & RES_DNSRCH))) {
+               int done = 0;
+
+               for (domain = (const char * const *)_res.dnsrch;
+                  *domain && !done;
+                  domain++) {
+
+                       ret = res_querydomainN(name, *domain, target);
+                       if (ret > 0)
+                               return (ret);
+
+                       /*
+                        * If no server present, give up.
+                        * If name isn't found in this domain,
+                        * keep trying higher domains in the search list
+                        * (if that's enabled).
+                        * On a NO_DATA error, keep trying, otherwise
+                        * a wildcard entry of another type could keep us
+                        * from finding this entry higher in the domain.
+                        * If we get some other error (negative answer or
+                        * server failure), then stop searching up,
+                        * but try the input name below in case it's
+                        * fully-qualified.
+                        */
+                       if (errno == ECONNREFUSED) {
+                               h_errno = TRY_AGAIN;
+                               return (-1);
+                       }
+
+                       switch (h_errno) {
+                       case NO_DATA:
+                               got_nodata++;
+                               /* FALLTHROUGH */
+                       case HOST_NOT_FOUND:
+                               /* keep trying */
+                               break;
+                       case TRY_AGAIN:
+                               if (hp->rcode == SERVFAIL) {
+                                       /* try next search element, if any */
+                                       got_servfail++;
+                                       break;
+                               }
+                               /* FALLTHROUGH */
+                       default:
+                               /* anything else implies that we're done */
+                               done++;
+                       }
+                       /*
+                        * if we got here for some reason other than DNSRCH,
+                        * we only wanted one iteration of the loop, so stop.
+                        */
+                       if (!(_res.options & RES_DNSRCH))
+                               done++;
+               }
+       }
+
+       /*
+        * if we have not already tried the name "as is", do that now.
+        * note that we do this regardless of how many dots were in the
+        * name or whether it ends with a dot.
+        */
+       if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) {
+               ret = res_querydomainN(name, NULL, target);
+               if (ret > 0)
+                       return (ret);
+       }
+
+       /*
+        * if we got here, we didn't satisfy the search.
+        * if we did an initial full query, return that query's h_errno
+        * (note that we wouldn't be here if that query had succeeded).
+        * else if we ever got a nodata, send that back as the reason.
+        * else send back meaningless h_errno, that being the one from
+        * the last DNSRCH we did.
+        */
+       if (saved_herrno != -1)
+               h_errno = saved_herrno;
+       else if (got_nodata)
+               h_errno = NO_DATA;
+       else if (got_servfail)
+               h_errno = TRY_AGAIN;
+       return (-1);
+}
+
+/*
+ * Perform a call on res_query on the concatenation of name and domain,
+ * removing a trailing dot from name if domain is NULL.
+ */
+static int
+res_querydomainN(name, domain, target)
+       const char *name, *domain;
+       struct res_target *target;
+{
+       char nbuf[MAXDNAME];
+       const char *longname = nbuf;
+       size_t n, d;
+
+       if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
+               h_errno = NETDB_INTERNAL;
+               return (-1);
+       }
+#ifdef DEBUG
+       if (_res.options & RES_DEBUG)
+               printf(";; res_querydomain(%s, %s)\n",
+                       name, domain?domain:"<Nil>");
+#endif
+       if (domain == NULL) {
+               /*
+                * Check for trailing '.';
+                * copy without '.' if present.
+                */
+               n = strlen(name);
+               if (n >= MAXDNAME) {
+                       h_errno = NO_RECOVERY;
+                       return (-1);
+               }
+               if (n > 0 && name[--n] == '.') {
+                       strncpy(nbuf, name, n);
+                       nbuf[n] = '\0';
+               } else
+                       longname = name;
+       } else {
+               n = strlen(name);
+               d = strlen(domain);
+               if (n + d + 1 >= MAXDNAME) {
+                       h_errno = NO_RECOVERY;
+                       return (-1);
+               }
+               sprintf(nbuf, "%s.%s", name, domain);
+       }
+       return (res_queryN(longname, target));
 }
Index: lib/libc/net/name6.c
diff -u lib/libc/net/name6.c.orig lib/libc/net/name6.c
--- lib/libc/net/name6.c.orig   Wed May 10 09:47:20 2000
+++ lib/libc/net/name6.c        Sun May 14 03:39:41 2000
@@ -169,18 +169,16 @@
 static int      _mapped_addr_enabled(void);
 
 static FILE    *_files_open(int *errp);
-static struct   hostent *_files_ghbyname(const char *name, int af, int *errp);
+static struct   hostent *_files_ghbyname(const char *name, int af, int flags, int 
+*errp);
 static struct   hostent *_files_ghbyaddr(const void *addr, int addrlen, int af, int 
*errp);
 static void     _files_shent(int stayopen);
 static void     _files_ehent(void);
 #ifdef YP
-static struct   hostent *_nis_ghbyname(const char *name, int af, int *errp);
+static struct   hostent *_nis_ghbyname(const char *name, int af, int flags, int 
+*errp);
 static struct   hostent *_nis_ghbyaddr(const void *addr, int addrlen, int af, int 
*errp);
 #endif
-static struct   hostent *_dns_ghbyname(const char *name, int af, int *errp);
+static struct   hostent *_dns_ghbyname(const char *name, int af, int flags, int 
+*errp);
 static struct   hostent *_dns_ghbyaddr(const void *addr, int addrlen, int af, int 
*errp);
-static void     _dns_shent(int stayopen);
-static void     _dns_ehent(void);
 #ifdef ICMPNL
 static struct   hostent *_icmp_ghbyaddr(const void *addr, int addrlen, int af, int 
*errp);
 #endif /* ICMPNL */
@@ -195,7 +193,7 @@
 #endif /* !HOSTCONF */
 
 struct _hostconf {
-       struct hostent *(*byname)(const char *name, int af, int *errp);
+       struct hostent *(*byname)(const char *name, int af, int flags, int *errp);
        struct hostent *(*byaddr)(const void *addr, int addrlen, int af, int *errp);
 };
 
@@ -344,7 +342,7 @@
 
        for (i = 0; i < MAXHOSTCONF; i++) {
                if (_hostconf[i].byname
-                && (hp = (*_hostconf[i].byname)(name, af, errp)) != NULL)
+                && (hp = (*_hostconf[i].byname)(name, af, flags, errp)) != NULL)
                        return hp;
        }
 
@@ -399,20 +397,8 @@
        hp = _ghbyname(name, af, flags, errp);
 
 #ifdef INET6
-       if (af == AF_INET6
-       &&  ((flags & AI_ALL) || hp == NULL)
-       &&  (MAPADDRENABLED(flags))) {
-               struct hostent *hp2 = _ghbyname(name, AF_INET, flags, errp);
-               if (hp == NULL)
-                       hp = _hpmapv6(hp2, errp);
-               else {
-                       if (hp2 && strcmp(hp->h_name, hp2->h_name) != 0) {
-                               freehostent(hp2);
-                               hp2 = NULL;
-                       }
-                       hp = _hpmerge(hp, hp2, errp);
-               }
-       }
+       if (af == AF_INET6 && hp != NULL && hp->h_addrtype == AF_INET)
+               hp = _hpmapv6(hp, errp);
 #endif
        return _hpsort(hp);
 }
@@ -829,20 +815,27 @@
 }
 
 static struct hostent *
-_files_ghbyname(const char *name, int af, int *errp)
+_files_ghbyname(const char *name, int af, int flags, int *errp)
 {
        int match, nalias;
        char *p, *line, *addrstr, *cname;
        FILE *fp;
-       struct hostent *rethp, *hp, hpbuf;
+       struct hostent **rethp, *rethp1, *rethp2, *hp, hpbuf;
        char *aliases[MAXALIASES + 1], *addrs[2];
        union inx_addr addrbuf;
        char buf[BUFSIZ];
        int af0 = af;
+#ifdef INET6
+       int mapaddrenabled;
+#endif
 
        if ((fp = _files_open(errp)) == NULL)
                return NULL;
-       rethp = hp = NULL;
+       rethp1 = rethp2 = hp = NULL;
+#ifdef INET6
+       if (af0 == AF_INET6)
+               mapaddrenabled = MAPADDRENABLED(flags);
+#endif
 
        while (fgets(buf, sizeof(buf), fp)) {
                line = buf;
@@ -859,6 +852,7 @@
                }
                if (!match)
                        continue;
+               rethp = &rethp1;
                switch (af0) {
                case AF_INET:
                        if (inet_aton(addrstr, (struct in_addr *)&addrbuf)
@@ -870,12 +864,20 @@
                        break;
 #ifdef INET6
                case AF_INET6:
-                       if (inet_pton(af, addrstr, &addrbuf) != 1) {
-                               *errp = NO_DATA;        /* name found */
-                               continue;
+                       if (inet_pton(af, addrstr, &addrbuf) == 1) {
+                               af = af0;
+                               break;
                        }
-                       af = af0;
-                       break;
+                       if (mapaddrenabled &&
+                           inet_aton(addrstr,
+                                     (struct in_addr *)&addrbuf) == 1) {
+                               af = AF_INET;
+                               rethp = &rethp2;
+                               break;
+                       }
+                       *errp = NO_DATA;        /* name found */
+                       continue;
+                       /* NOTREACHED */
 #endif
                case AF_UNSPEC:
                        if (inet_aton(addrstr, (struct in_addr *)&addrbuf)
@@ -903,10 +905,21 @@
                addrs[0] = (char *)&addrbuf;
                addrs[1] = NULL;
                hp = _hpcopy(hp, errp);
-               rethp = _hpmerge(rethp, hp, errp);
+               *rethp = _hpmerge(*rethp, hp, errp);
        }
        fclose(fp);
-       return rethp;
+       rethp = &rethp1;
+#ifdef INET6
+       if (af0 == AF_INET6) {
+               if ((flags & AI_ALL))
+                       *rethp = _hpmerge(rethp1, rethp2, errp);
+               else if (rethp1 == NULL)
+                       rethp = &rethp2;
+               else if (rethp2 != NULL)
+                       freehostent(rethp2);
+       }
+#endif
+       return *rethp;
 }
 
 static struct hostent *
@@ -960,7 +973,7 @@
  * XXX actually a hack, these are INET4 specific.
  */
 static struct hostent *
-_nis_ghbyname(const char *name, int af, int *errp)
+_nis_ghbyname(const char *name, int af, int flags, int *errp)
 {
        struct hostent *hp = NULL;
 
@@ -989,11 +1002,6 @@
 }
 #endif
 
-struct __res_type_list {
-        SLIST_ENTRY(__res_type_list) rtl_entry;
-        int     rtl_type;
-};
-
 #if PACKETSZ > 1024
 #define        MAXPACKET       PACKETSZ
 #else
@@ -1005,8 +1013,21 @@
        u_char buf[MAXPACKET];
 } querybuf;
 
+struct res_target {
+       struct res_target *next;
+       const char *name;       /* domain name */
+       int class, type;        /* class and type of query */
+       u_char *answer;         /* buffer to put answer */
+       int anslen;             /* size of answer buffer */
+       int n;                  /* result length */
+};
+
 static struct hostent *getanswer __P((const querybuf *, int, const char *,
        int, struct hostent *, int *));
+static int res_queryN __P((const char *, struct res_target *));
+static int res_searchN __P((const char *, struct res_target *));
+static int res_querydomainN __P((const char *, const char *,
+       struct res_target *));
 
 /*
  * we don't need to take care about sorting, nor IPv4 mapped address here.
@@ -1287,26 +1308,140 @@
 #undef DNS_FATAL
 }
 
-/* res_search() variant with multiple query support. */
-static struct hostent *
-_res_search_multi(name, rtl, errp)
+extern const char *__hostalias __P((const char *));
+
+/*
+ * Formulate a normal query, send, and await answer.
+ * Returned answer is placed in supplied buffer "answer".
+ * Perform preliminary check of answer, returning success only
+ * if no error is indicated and the answer count is nonzero.
+ * Return the size of the response on success, -1 on error.
+ * Error number is left in h_errno.
+ *
+ * Caller must parse answer and determine whether it answers the question.
+ */
+static int
+res_queryN(name, target)
        const char *name;       /* domain name */
-       struct  __res_type_list *rtl; /* list of query types */
-       int *errp;
+       struct res_target *target;
+{
+       u_char buf[MAXPACKET];
+       HEADER *hp;
+       int n;
+       struct res_target *t;
+       int rcode;
+       int ancount;
+
+       rcode = NOERROR;
+       ancount = 0;
+
+       if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
+               h_errno = NETDB_INTERNAL;
+               return (-1);
+       }
+
+       for (t = target; t; t = t->next) {
+               int class, type;
+               u_char *answer;
+               int anslen;
+
+               hp = (HEADER *)(void *)t->answer;
+               hp->rcode = NOERROR;    /* default */
+
+               /* make it easier... */
+               class = t->class;
+               type = t->type;
+               answer = t->answer;
+               anslen = t->anslen;
+#ifdef DEBUG
+               if (_res.options & RES_DEBUG)
+                       printf(";; res_query(%s, %d, %d)\n", name, class, type);
+#endif
+
+               n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL,
+                   buf, sizeof(buf));
+               if (n <= 0) {
+#ifdef DEBUG
+                       if (_res.options & RES_DEBUG)
+                               printf(";; res_query: mkquery failed\n");
+#endif
+                       h_errno = NO_RECOVERY;
+                       return (n);
+               }
+               n = res_send(buf, n, answer, anslen);
+#if 0
+               if (n < 0) {
+#ifdef DEBUG
+                       if (_res.options & RES_DEBUG)
+                               printf(";; res_query: send error\n");
+#endif
+                       h_errno = TRY_AGAIN;
+                       return (n);
+               }
+#endif
+
+               if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
+                       rcode = hp->rcode;      /* record most recent error */
+#ifdef DEBUG
+                       if (_res.options & RES_DEBUG)
+                               printf(";; rcode = %d, ancount=%d\n", hp->rcode,
+                                   ntohs(hp->ancount));
+#endif
+                       continue;
+               }
+
+               ancount += ntohs(hp->ancount);
+
+               t->n = n;
+       }
+
+       if (ancount == 0) {
+               switch (rcode) {
+               case NXDOMAIN:
+                       h_errno = HOST_NOT_FOUND;
+                       break;
+               case SERVFAIL:
+                       h_errno = TRY_AGAIN;
+                       break;
+               case NOERROR:
+                       h_errno = NO_DATA;
+                       break;
+               case FORMERR:
+               case NOTIMP:
+               case REFUSED:
+               default:
+                       h_errno = NO_RECOVERY;
+                       break;
+               }
+               return (-1);
+       }
+       return (ancount);
+}
+
+/*
+ * Formulate a normal query, send, and retrieve answer in supplied buffer.
+ * Return the size of the response on success, -1 on error.
+ * If enabled, implement search rules until answer or unrecoverable failure
+ * is detected.  Error code, if any, is left in h_errno.
+ */
+static int
+res_searchN(name, target)
+       const char *name;       /* domain name */
+       struct res_target *target;
 {
        const char *cp, * const *domain;
-       struct hostent *hp0 = NULL, *hp;
-       struct hostent hpbuf;
+       HEADER *hp = (HEADER *)(void *)target->answer;  /*XXX*/
        u_int dots;
        int trailing_dot, ret, saved_herrno;
        int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
-       struct __res_type_list *rtl0 = rtl;
-       querybuf buf;
 
        if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
-               *errp = NETDB_INTERNAL;
-               return (NULL);
+               h_errno = NETDB_INTERNAL;
+               return (-1);
        }
+
+       errno = 0;
+       h_errno = HOST_NOT_FOUND;       /* default, if we never query */
        dots = 0;
        for (cp = name; *cp; cp++)
                dots += (*cp == '.');
@@ -1314,24 +1449,11 @@
        if (cp > name && *--cp == '.')
                trailing_dot++;
 
-       /* If there aren't any dots, it could be a user-level alias */
-       if (!dots && (cp = hostalias(name)) != NULL) {
-               for(rtl = rtl0; rtl != NULL;
-                   rtl = SLIST_NEXT(rtl, rtl_entry)) {
-                       ret = res_query(cp, C_IN, rtl->rtl_type, buf.buf,
-                                            sizeof(buf.buf));
-                       if (ret > 0) {
-                               hpbuf.h_addrtype = (rtl->rtl_type == T_AAAA)
-                                   ? AF_INET6 : AF_INET;
-                               hpbuf.h_length = ADDRLEN(hpbuf.h_addrtype);
-                               hp = getanswer(&buf, ret, name, rtl->rtl_type,
-                                                   &hpbuf, errp);
-                               hp = _hpcopy(&hpbuf, errp);
-                               hp0 = _hpmerge(hp0, hp, errp);
-                       }
-               }
-               return (hp0);
-       }
+       /*
+        * if there aren't any dots, it could be a user-level alias
+        */
+       if (!dots && (cp = __hostalias(name)) != NULL)
+               return (res_queryN(cp, target));
 
        /*
         * If there are dots in the name already, let's just give it a try
@@ -1339,23 +1461,10 @@
         */
        saved_herrno = -1;
        if (dots >= _res.ndots) {
-               for(rtl = rtl0; rtl != NULL;
-                   rtl = SLIST_NEXT(rtl, rtl_entry)) {
-                       ret = res_querydomain(name, NULL, C_IN, rtl->rtl_type,
-                                             buf.buf, sizeof(buf.buf));
-                       if (ret > 0) {
-                               hpbuf.h_addrtype = (rtl->rtl_type == T_AAAA)
-                                   ? AF_INET6 : AF_INET;
-                               hpbuf.h_length = ADDRLEN(hpbuf.h_addrtype);
-                               hp = getanswer(&buf, ret, name, rtl->rtl_type,
-                                                   &hpbuf, errp);
-                               hp = _hpcopy(&hpbuf, errp);
-                               hp0 = _hpmerge(hp0, hp, errp);
-                       }
-               }
-               if (hp0 != NULL)
-                       return (hp0);
-               saved_herrno = *errp;
+               ret = res_querydomainN(name, NULL, target);
+               if (ret > 0)
+                       return (ret);
+               saved_herrno = h_errno;
                tried_as_is++;
        }
 
@@ -1370,26 +1479,12 @@
                int done = 0;
 
                for (domain = (const char * const *)_res.dnsrch;
-                    *domain && !done;
-                    domain++) {
+                  *domain && !done;
+                  domain++) {
 
-                       for(rtl = rtl0; rtl != NULL;
-                           rtl = SLIST_NEXT(rtl, rtl_entry)) {
-                               ret = res_querydomain(name, *domain, C_IN,
-                                                     rtl->rtl_type,
-                                                     buf.buf, sizeof(buf.buf));
-                               if (ret > 0) {
-                                       hpbuf.h_addrtype = (rtl->rtl_type == T_AAAA)
-                                           ? AF_INET6 : AF_INET;
-                                       hpbuf.h_length = ADDRLEN(hpbuf.h_addrtype);
-                                       hp = getanswer(&buf, ret, name,
-                                           rtl->rtl_type, &hpbuf, errp);
-                                       hp = _hpcopy(&hpbuf, errp);
-                                       hp0 = _hpmerge(hp0, hp, errp);
-                               }
-                       }
-                       if (hp0 != NULL)
-                               return (hp0);
+                       ret = res_querydomainN(name, *domain, target);
+                       if (ret > 0)
+                               return (ret);
 
                        /*
                         * If no server present, give up.
@@ -1405,11 +1500,11 @@
                         * fully-qualified.
                         */
                        if (errno == ECONNREFUSED) {
-                               *errp = TRY_AGAIN;
-                               return (NULL);
+                               h_errno = TRY_AGAIN;
+                               return (-1);
                        }
 
-                       switch (*errp) {
+                       switch (h_errno) {
                        case NO_DATA:
                                got_nodata++;
                                /* FALLTHROUGH */
@@ -1417,7 +1512,7 @@
                                /* keep trying */
                                break;
                        case TRY_AGAIN:
-                               if (buf.hdr.rcode == SERVFAIL) {
+                               if (hp->rcode == SERVFAIL) {
                                        /* try next search element, if any */
                                        got_servfail++;
                                        break;
@@ -1427,40 +1522,28 @@
                                /* anything else implies that we're done */
                                done++;
                        }
-
-                       /* if we got here for some reason other than DNSRCH,
+                       /*
+                        * if we got here for some reason other than DNSRCH,
                         * we only wanted one iteration of the loop, so stop.
                         */
                        if (!(_res.options & RES_DNSRCH))
-                               done++;
+                               done++;
                }
        }
 
        /*
-        * If we have not already tried the name "as is", do that now.
+        * if we have not already tried the name "as is", do that now.
         * note that we do this regardless of how many dots were in the
-        * name or whether it ends with a dot unless NOTLDQUERY is set.
+        * name or whether it ends with a dot.
         */
        if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) {
-               for(rtl = rtl0; rtl != NULL;
-                   rtl = SLIST_NEXT(rtl, rtl_entry)) {
-                       ret = res_querydomain(name, NULL, C_IN, rtl->rtl_type,
-                                             buf.buf, sizeof(buf.buf));
-                       if (ret > 0) {
-                               hpbuf.h_addrtype = (rtl->rtl_type == T_AAAA)
-                                   ? AF_INET6 : AF_INET;
-                               hpbuf.h_length = ADDRLEN(hpbuf.h_addrtype);
-                               hp = getanswer(&buf, ret, name, rtl->rtl_type,
-                                   &hpbuf, errp);
-                               hp = _hpcopy(&hpbuf, errp);
-                               hp0 = _hpmerge(hp0, hp, errp);
-                       }
-               }
-               if (hp0 != NULL)
-                       return (hp0);
+               ret = res_querydomainN(name, NULL, target);
+               if (ret > 0)
+                       return (ret);
        }
 
-       /* if we got here, we didn't satisfy the search.
+       /*
+        * if we got here, we didn't satisfy the search.
         * if we did an initial full query, return that query's h_errno
         * (note that we wouldn't be here if that query had succeeded).
         * else if we ever got a nodata, send that back as the reason.
@@ -1468,43 +1551,139 @@
         * the last DNSRCH we did.
         */
        if (saved_herrno != -1)
-               *errp = saved_herrno;
+               h_errno = saved_herrno;
        else if (got_nodata)
-               *errp = NO_DATA;
+               h_errno = NO_DATA;
        else if (got_servfail)
-               *errp = TRY_AGAIN;
-       return (NULL);
+               h_errno = TRY_AGAIN;
+       return (-1);
+}
+
+/*
+ * Perform a call on res_query on the concatenation of name and domain,
+ * removing a trailing dot from name if domain is NULL.
+ */
+static int
+res_querydomainN(name, domain, target)
+       const char *name, *domain;
+       struct res_target *target;
+{
+       char nbuf[MAXDNAME];
+       const char *longname = nbuf;
+       size_t n, d;
+
+       if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
+               h_errno = NETDB_INTERNAL;
+               return (-1);
+       }
+#ifdef DEBUG
+       if (_res.options & RES_DEBUG)
+               printf(";; res_querydomain(%s, %s)\n",
+                       name, domain?domain:"<Nil>");
+#endif
+       if (domain == NULL) {
+               /*
+                * Check for trailing '.';
+                * copy without '.' if present.
+                */
+               n = strlen(name);
+               if (n >= MAXDNAME) {
+                       h_errno = NO_RECOVERY;
+                       return (-1);
+               }
+               if (n > 0 && name[--n] == '.') {
+                       strncpy(nbuf, name, n);
+                       nbuf[n] = '\0';
+               } else
+                       longname = name;
+       } else {
+               n = strlen(name);
+               d = strlen(domain);
+               if (n + d + 1 >= MAXDNAME) {
+                       h_errno = NO_RECOVERY;
+                       return (-1);
+               }
+               sprintf(nbuf, "%s.%s", name, domain);
+       }
+       return (res_queryN(longname, target));
 }
 
 static struct hostent *
-_dns_ghbyname(const char *name, int af, int *errp)
+_dns_ghbyname(const char *name, int af, int flags, int *errp)
 {
-       struct __res_type_list *rtl, rtl4;
-#ifdef INET6
-       struct __res_type_list rtl6;
-#endif
+       struct hostent *hp, *hp2;
+       struct hostent hbuf;
+       querybuf buf, buf2;
+       struct res_target q, q2;
 
-#ifdef INET6
+       if ((_res.options & RES_INIT) == 0) {
+               if (res_init() < 0) {
+                       *errp = h_errno;
+                       return NULL;
+               }
+       }
+
+       memset(&q, 0, sizeof(q2));
+       memset(&q2, 0, sizeof(q2));
        switch (af) {
        case AF_UNSPEC:
-               SLIST_NEXT(&rtl4, rtl_entry) = NULL; rtl4.rtl_type = T_A;
-               SLIST_NEXT(&rtl6, rtl_entry) = &rtl4; rtl6.rtl_type = T_AAAA;
-               rtl = &rtl6;
-               break;
-       case AF_INET6:
-               SLIST_NEXT(&rtl6, rtl_entry) = NULL; rtl6.rtl_type = T_AAAA;
-               rtl = &rtl6;
+#ifdef INET6
+               /* prefer IPv6 */
+               q.class = C_IN;
+               q.type = T_AAAA;
+               q.answer = buf.buf;
+               q.anslen = sizeof(buf);
+               q.next = &q2;
+               q2.class = C_IN;
+               q2.type = T_A;
+               q2.answer = buf2.buf;
+               q2.anslen = sizeof(buf2);
                break;
+#endif
        case AF_INET:
-               SLIST_NEXT(&rtl4, rtl_entry) = NULL; rtl4.rtl_type = T_A;
-               rtl = &rtl4;
+               q.class = C_IN;
+               q.type = T_A;
+               q.answer = buf.buf;
+               q.anslen = sizeof(buf);
+               break;
+#ifdef INET6
+       case AF_INET6:
+               q.class = C_IN;
+               q.type = T_AAAA;
+               q.answer = buf.buf;
+               q.anslen = sizeof(buf);
+               if (MAPADDRENABLED(flags)) {
+                       q.next = &q2;
+                       q2.class = C_IN;
+                       q2.type = T_A;
+                       q2.answer = buf2.buf;
+                       q2.anslen = sizeof(buf2);
+               }
                break;
-       }
-#else
-       SLIST_NEXT(&rtl4, rtl_entry) = NULL; rtl4.rtl_type = T_A;
-       rtl = &rtl4;
 #endif
-       return(_res_search_multi(name, rtl, errp));
+       default:
+               *errp = NO_RECOVERY;
+               return NULL;
+       }
+       if (res_searchN(name, &q) < 0) {
+               *errp = h_errno;
+               return NULL;
+       }
+       memset(&hbuf, 0, sizeof(hbuf));
+       hbuf.h_addrtype = (q.type == T_AAAA) ? AF_INET6 : AF_INET;
+       hbuf.h_length = ADDRLEN(hbuf.h_addrtype);
+       hp = getanswer(&buf, q.n, q.name, q.type, &hbuf, errp);
+       hp = _hpcopy(hp, errp);
+       if (q.next == NULL)
+               return hp;
+       if (hp != NULL && af == AF_INET6 && !(flags & AI_ALL))
+               return hp;
+       memset(&hbuf, 0, sizeof(hbuf));
+       hbuf.h_addrtype = (q2.type == T_AAAA) ? AF_INET6 : AF_INET;
+       hbuf.h_length = ADDRLEN(hbuf.h_addrtype);
+       hp2 = getanswer(&buf2, q2.n, q2.name, q2.type, &hbuf, errp);
+       hp2 = _hpcopy(hp2, errp);
+       return _hpmerge(hp, hp2, errp);
 }
 
 static struct hostent *
@@ -1584,24 +1763,6 @@
        hlist[0] = (char *)addr;
        hlist[1] = NULL;
        return _hpcopy(&hbuf, errp);
-}
-
-static void
-_dns_shent(int stayopen)
-{
-       if ((_res.options & RES_INIT) == 0) {
-               if (res_init() < 0)
-                       return;
-       }
-       if (stayopen)
-               _res.options |= RES_STAYOPEN | RES_USEVC;
-}
-
-static void
-_dns_ehent(void)
-{
-       _res.options &= ~(RES_STAYOPEN | RES_USEVC);
-       res_close();
 }
 
 #ifdef ICMPNL
Hajimu UMEMOTO @ Internet Mutual Aid Society Yokohama, Japan
[EMAIL PROTECTED]  [EMAIL PROTECTED]  [EMAIL PROTECTED]
http://www.imasy.org/~ume/

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