use connect on dg sockets to allow unreachable reporting;

[unix-history] / usr / src / lib / libc / net / res_send.c

diff --git a/usr/src/lib/libc/net/res_send.c b/usr/src/lib/libc/net/res_send.c
index dfd75e7..9e37090 100644 (file)
--- a/usr/src/lib/libc/net/res_send.c
+++ b/usr/src/lib/libc/net/res_send.c
@@ -1,3 +1,4 @@
+

 /*
  * Copyright (c) 1985 Regents of the University of California.
  * All rights reserved.  The Berkeley software License Agreement
 /*
  * Copyright (c) 1985 Regents of the University of California.
  * All rights reserved.  The Berkeley software License Agreement


@@ -5,7 +6,7 @@
  */
 
 #ifndef lint
  */
 
 #ifndef lint

-static char sccsid[] = "@(#)res_send.c 5.5 (Berkeley) %G%";
+static char sccsid[] = "@(#)res_send.c 6.3 (Berkeley) %G%";

 #endif not lint
 
 /*
 #endif not lint
 
 /*


@@ -23,6 +24,8 @@ static char sccsid[] = "@(#)res_send.c        5.5 (Berkeley) %G%";
 
 extern int errno;
 
 
 extern int errno;
 

+#define KEEPOPEN (RES_USEVC|RES_STAYOPEN)
+

 res_send(buf, buflen, answer, anslen)
        char *buf;
        int buflen;
 res_send(buf, buflen, answer, anslen)
        char *buf;
        int buflen;


@@ -30,7 +33,8 @@ res_send(buf, buflen, answer, anslen)
        int anslen;
 {
        register int n;
        int anslen;
 {
        register int n;

-       int s, retry, v_circuit, resplen;
+       int retry, v_circuit, resplen, ns;
+       static int s = -1;

        u_short id, len;
        char *cp;
        int dsmask;
        u_short id, len;
        char *cp;
        int dsmask;


@@ -43,43 +47,50 @@ res_send(buf, buflen, answer, anslen)
                printf("res_send()\n");
                p_query(buf);
        }
                printf("res_send()\n");
                p_query(buf);
        }

-#endif
+#endif DEBUG

        if (!(_res.options & RES_INIT))
                if (res_init() == -1) {
                        return(-1);
                }
        if (!(_res.options & RES_INIT))
                if (res_init() == -1) {
                        return(-1);
                }

-       s = -1;

        v_circuit = (_res.options & RES_USEVC) || buflen > PACKETSZ;
        id = hp->id;
        /*
         * Send request, RETRY times, or until successful
         */
        for (retry = _res.retry; --retry >= 0; ) {
        v_circuit = (_res.options & RES_USEVC) || buflen > PACKETSZ;
        id = hp->id;
        /*
         * Send request, RETRY times, or until successful
         */
        for (retry = _res.retry; --retry >= 0; ) {

+          for (ns = 0; ns < _res.nscount; ns++) {
+#ifdef DEBUG
+               if (_res.options & RES_DEBUG)
+                       printf("Querying server (# %d) address = %s\n", ns+1,
+                             inet_ntoa(_res.nsaddr_list[ns].sin_addr.s_addr)); 
+#endif DEBUG

                if (v_circuit) {
                        /*
                         * Use virtual circuit.
                         */
                if (v_circuit) {
                        /*
                         * Use virtual circuit.
                         */

-                       if (s < 0)
+                       if (s < 0) {

                                s = socket(AF_INET, SOCK_STREAM, 0);
                                s = socket(AF_INET, SOCK_STREAM, 0);

-                       if (connect(s, &_res.nsaddr, sizeof(_res.nsaddr)) < 0) {
+                               if (connect(s, &(_res.nsaddr_list[ns]), 
+                                  sizeof(struct sockaddr)) < 0) {

 #ifdef DEBUG
 #ifdef DEBUG

-                               if (_res.options & RES_DEBUG)
-                                       printf("connect failed %d\n", errno);
-#endif
-                               (void) close(s);
-                               s = -1;
-                               continue;
+                                       if (_res.options & RES_DEBUG)
+                                           printf("connect failed %d\n",errno);
+#endif DEBUG
+                                       (void) close(s);
+                                       s = -1;
+                                       continue;
+                               }

                        }
                        /*
                         * Send length & message
                         */
                        len = htons(buflen);
                        if (write(s, &len, sizeof(len)) != sizeof(len) ||
                        }
                        /*
                         * Send length & message
                         */
                        len = htons(buflen);
                        if (write(s, &len, sizeof(len)) != sizeof(len) ||

-                           write(s, buf, buflen) != buflen) {
+                                   write(s, buf, buflen) != buflen) {

 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("write failed %d\n", errno);
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("write failed %d\n", errno);

-#endif
+#endif DEBUG

                                (void) close(s);
                                s = -1;
                                continue;
                                (void) close(s);
                                s = -1;
                                continue;


@@ -97,7 +108,7 @@ res_send(buf, buflen, answer, anslen)
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("read failed %d\n", errno);
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("read failed %d\n", errno);

-#endif
+#endif DEBUG

                                (void) close(s);
                                s = -1;
                                continue;
                                (void) close(s);
                                s = -1;
                                continue;


@@ -112,7 +123,7 @@ res_send(buf, buflen, answer, anslen)
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("read failed %d\n", errno);
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("read failed %d\n", errno);

-#endif
+#endif DEBUG

                                (void) close(s);
                                s = -1;
                                continue;
                                (void) close(s);
                                s = -1;
                                continue;


@@ -123,25 +134,29 @@ res_send(buf, buflen, answer, anslen)
                         */
                        if (s < 0)
                                s = socket(AF_INET, SOCK_DGRAM, 0);
                         */
                        if (s < 0)
                                s = socket(AF_INET, SOCK_DGRAM, 0);

-                       if (sendto(s, buf, buflen, 0, &_res.nsaddr,
-                           sizeof(_res.nsaddr)) != buflen) {
+                       if (connect(s, &_res.nsaddr_list[ns],
+                           sizeof(struct sockaddr)) < 0 ||
+                           send(s, buf, buflen, 0) != buflen) {

 #ifdef DEBUG
 #ifdef DEBUG

-                               if (_res.options & RES_DEBUG)
-                                       printf("sendto errno = %d\n", errno);
-#endif
+                               if (_res.options & RES_DEBUG) 
+                                       printf("connect/send errno = %d\n",
+                                           errno);
+#endif DEBUG

                        }
                        /*
                         * Wait for reply 
                         */
                        }
                        /*
                         * Wait for reply 
                         */

-                       timeout.tv_sec = _res.retrans;
+                       timeout.tv_sec = 
+                               ((_res.retrans * _res.retry) / _res.nscount);

                        timeout.tv_usec = 0;
                        timeout.tv_usec = 0;

+wait:

                        dsmask = 1 << s;
                        n = select(s+1, &dsmask, 0, 0, &timeout);
                        if (n < 0) {
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("select errno = %d\n", errno);
                        dsmask = 1 << s;
                        n = select(s+1, &dsmask, 0, 0, &timeout);
                        if (n < 0) {
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("select errno = %d\n", errno);

-#endif
+#endif DEBUG

                                continue;
                        }
                        if (n == 0) {
                                continue;
                        }
                        if (n == 0) {


@@ -151,15 +166,14 @@ res_send(buf, buflen, answer, anslen)
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("timeout\n");
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("timeout\n");

-#endif
+#endif DEBUG

                                continue;
                        }
                                continue;
                        }

-                       if ((resplen = recvfrom(s, answer, anslen,
-                           0, 0, 0)) <= 0) {
+                       if ((resplen = recv(s, answer, anslen, 0)) <= 0) {

 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("recvfrom, errno=%d\n", errno);
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("recvfrom, errno=%d\n", errno);

-#endif
+#endif DEBUG

                                continue;
                        }
                        if (id != anhp->id) {
                                continue;
                        }
                        if (id != anhp->id) {


@@ -171,8 +185,8 @@ res_send(buf, buflen, answer, anslen)
                                        printf("old answer:\n");
                                        p_query(answer);
                                }
                                        printf("old answer:\n");
                                        p_query(answer);
                                }

-#endif
-                               continue;
+#endif DEBUG
+                               goto wait;

                        }
                        if (!(_res.options & RES_IGNTC) && anhp->tc) {
                                /*
                        }
                        if (!(_res.options & RES_IGNTC) && anhp->tc) {
                                /*


@@ -181,7 +195,7 @@ res_send(buf, buflen, answer, anslen)
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("truncated answer\n");
 #ifdef DEBUG
                                if (_res.options & RES_DEBUG)
                                        printf("truncated answer\n");

-#endif
+#endif DEBUG

                                (void) close(s);
                                s = -1;
                                retry = _res.retry;
                                (void) close(s);
                                s = -1;
                                retry = _res.retry;


@@ -194,9 +208,20 @@ res_send(buf, buflen, answer, anslen)
                        printf("got answer:\n");
                        p_query(answer);
                }
                        printf("got answer:\n");
                        p_query(answer);
                }

-#endif
-               (void) close(s);
-               return (resplen);
+#endif DEBUG
+               /*
+                * We are going to assume that the first server is preferred
+                * over the rest (i.e. it is on the local machine) and only
+                * keep that one open.
+                */
+               if ((_res.options & KEEPOPEN) == KEEPOPEN && ns == 0) {
+                       return (resplen);
+               } else {
+                       (void) close(s);
+                       s = -1;
+                       return (resplen);
+               }
+          }

        }
        (void) close(s);
        errno = ETIMEDOUT;
        }
        (void) close(s);
        errno = ETIMEDOUT;