install C version of _doprnt

[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 443d733..36b23fe 100644 (file)
--- a/usr/src/lib/libc/net/res_send.c
+++ b/usr/src/lib/libc/net/res_send.c
@@ -1,28 +1,50 @@
 /*
  * Copyright (c) 1985 Regents of the University of California.
 /*
  * Copyright (c) 1985 Regents of the University of California.

- * All rights reserved.  The Berkeley software License Agreement
- * specifies the terms and conditions for redistribution.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that this notice is preserved and that due credit is given
+ * to the University of California at Berkeley. The name of the University
+ * may not be used to endorse or promote products derived from this
+ * software without specific prior written permission. This software
+ * is provided ``as is'' without express or implied warranty.

  */
 
  */
 

-#ifndef lint
-static char sccsid[] = "@(#)res_send.c 5.2 (Berkeley) %G%";
-#endif not lint
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)res_send.c 6.19 (Berkeley) %G%";
+#endif /* LIBC_SCCS and not lint */

 
 /*
  * Send query to name server and wait for reply.
  */
 
 
 /*
  * Send query to name server and wait for reply.
  */
 

-#include <sys/types.h>
+#include <sys/param.h>

 #include <sys/time.h>
 #include <sys/socket.h>
 #include <sys/time.h>
 #include <sys/socket.h>

+#include <sys/uio.h>

 #include <netinet/in.h>
 #include <stdio.h>
 #include <errno.h>
 #include <netinet/in.h>
 #include <stdio.h>
 #include <errno.h>

-#include <nameser.h>
+#include <arpa/nameser.h>

 #include <resolv.h>
 
 extern int errno;
 
 #include <resolv.h>
 
 extern int errno;
 

+static int s = -1;     /* socket used for communications */
+static struct sockaddr no_addr;
+  
+
+#ifndef FD_SET
+#define        NFDBITS         32
+#define        FD_SETSIZE      32
+#define        FD_SET(n, p)    ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
+#define        FD_CLR(n, p)    ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
+#define        FD_ISSET(n, p)  ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
+#define FD_ZERO(p)     bzero((char *)(p), sizeof(*(p)))
+#endif
+
+#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;


@@ -30,48 +52,82 @@ 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;
+       int gotsomewhere = 0, connected = 0;

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

-       int dsmask;
+       fd_set dsmask;

        struct timeval timeout;
        HEADER *hp = (HEADER *) buf;
        HEADER *anhp = (HEADER *) answer;
        struct timeval timeout;
        HEADER *hp = (HEADER *) buf;
        HEADER *anhp = (HEADER *) answer;

+       struct iovec iov[2];
+       int terrno = ETIMEDOUT;
+       char junk[512];

 
 

+#ifdef DEBUG

        if (_res.options & RES_DEBUG) {
                printf("res_send()\n");
                p_query(buf);
        }
        if (_res.options & RES_DEBUG) {
                printf("res_send()\n");
                p_query(buf);
        }

+#endif DEBUG

        if (!(_res.options & RES_INIT))
        if (!(_res.options & RES_INIT))

-               res_init();
-       s = -1;
+               if (res_init() == -1) {
+                       return(-1);
+               }

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

                if (v_circuit) {
                if (v_circuit) {

+                       int truncated = 0;
+

                        /*
                         * Use virtual 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 (_res.options & RES_DEBUG)
-                                       printf("connect failed %d\n", errno);
-                               (void) close(s);
-                               s = -1;
-                               continue;
+                               if (s < 0) {
+                                       terrno = errno;
+#ifdef DEBUG
+                                       if (_res.options & RES_DEBUG)
+                                           perror("socket failed");
+#endif DEBUG
+                                       continue;
+                               }
+                               if (connect(s, &(_res.nsaddr_list[ns]),
+                                  sizeof(struct sockaddr)) < 0) {
+                                       terrno = errno;
+#ifdef DEBUG
+                                       if (_res.options & RES_DEBUG)
+                                           perror("connect failed");
+#endif DEBUG
+                                       (void) close(s);
+                                       s = -1;
+                                       continue;
+                               }

                        }
                        /*
                         * Send length & message
                         */
                        }
                        /*
                         * Send length & message
                         */

-                       len = htons(buflen);
-                       if (write(s, &len, sizeof(len)) != sizeof(len) ||
-                           write(s, buf, buflen) != buflen) {
+                       len = htons((u_short)buflen);
+                       iov[0].iov_base = (caddr_t)&len;
+                       iov[0].iov_len = sizeof(len);
+                       iov[1].iov_base = buf;
+                       iov[1].iov_len = buflen;
+                       if (writev(s, iov, 2) != sizeof(len) + buflen) {
+                               terrno = errno;
+#ifdef DEBUG

                                if (_res.options & RES_DEBUG)
                                if (_res.options & RES_DEBUG)

-                                       printf("write failed %d\n", errno);
+                                       perror("write failed");
+#endif DEBUG

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


@@ -81,97 +137,228 @@ res_send(buf, buflen, answer, anslen)
                         */
                        cp = answer;
                        len = sizeof(short);
                         */
                        cp = answer;
                        len = sizeof(short);

-                       while (len > 0 && (n = read(s, cp, len)) > 0) {
+                       while (len != 0 &&
+                           (n = read(s, (char *)cp, (int)len)) > 0) {

                                cp += n;
                                len -= n;
                        }
                        if (n <= 0) {
                                cp += n;
                                len -= n;
                        }
                        if (n <= 0) {

+                               terrno = errno;
+#ifdef DEBUG

                                if (_res.options & RES_DEBUG)
                                if (_res.options & RES_DEBUG)

-                                       printf("read failed %d\n", errno);
+                                       perror("read failed");
+#endif DEBUG

                                (void) close(s);
                                s = -1;
                                continue;
                        }
                        cp = answer;
                                (void) close(s);
                                s = -1;
                                continue;
                        }
                        cp = answer;

-                       resplen = len = ntohs(*(short *)cp);
-                       while (len > 0 && (n = read(s, cp, len)) > 0) {
+                       if ((resplen = ntohs(*(u_short *)cp)) > anslen) {
+#ifdef DEBUG
+                               if (_res.options & RES_DEBUG)
+                                       fprintf(stderr, "response truncated\n");
+#endif DEBUG
+                               len = anslen;
+                               truncated = 1;
+                       } else
+                               len = resplen;
+                       while (len != 0 &&
+                          (n = read(s, (char *)cp, (int)len)) > 0) {

                                cp += n;
                                len -= n;
                        }
                        if (n <= 0) {
                                cp += n;
                                len -= n;
                        }
                        if (n <= 0) {

+                               terrno = errno;
+#ifdef DEBUG

                                if (_res.options & RES_DEBUG)
                                if (_res.options & RES_DEBUG)

-                                       printf("read failed %d\n", errno);
+                                       perror("read failed");
+#endif DEBUG

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

+                       if (truncated) {
+                               /*
+                                * Flush rest of answer
+                                * so connection stays in synch.
+                                */
+                               anhp->tc = 1;
+                               len = resplen - anslen;
+                               while (len != 0) {
+                                       n = (len > sizeof(junk) ?
+                                           sizeof(junk) : len);
+                                       if ((n = read(s, junk, n)) > 0)
+                                               len -= n;
+                                       else
+                                               break;
+                               }
+                       }

                } else {
                        /*
                         * Use datagrams.
                         */
                        if (s < 0)
                                s = socket(AF_INET, SOCK_DGRAM, 0);
                } else {
                        /*
                         * Use datagrams.
                         */
                        if (s < 0)
                                s = socket(AF_INET, SOCK_DGRAM, 0);

-                       if (sendto(s, buf, buflen, 0, &_res.nsaddr,
-                           sizeof(_res.nsaddr)) != buflen) {
+#if    BSD >= 43
+                       if (_res.nscount == 1 || retry == _res.retry) {
+                               /*
+                                * Don't use connect if we might
+                                * still receive a response
+                                * from another server.
+                                */
+                               if (connected == 0) {
+                                       if (connect(s, &_res.nsaddr_list[ns],
+                                           sizeof(struct sockaddr)) < 0) {
+#ifdef DEBUG
+                                               if (_res.options & RES_DEBUG)
+                                                       perror("connect");
+#endif DEBUG
+                                               continue;
+                                       }
+                                       connected = 1;
+                               }
+                               if (send(s, buf, buflen, 0) != buflen) {
+#ifdef DEBUG
+                                       if (_res.options & RES_DEBUG)
+                                               perror("send");
+#endif DEBUG
+                                       continue;
+                               }
+                       } else
+#endif BSD
+                       if (sendto(s, buf, buflen, 0, &_res.nsaddr_list[ns],
+                           sizeof(struct sockaddr)) != buflen) {
+#ifdef DEBUG

                                if (_res.options & RES_DEBUG)
                                if (_res.options & RES_DEBUG)

-                                       printf("sendto errno = %d\n", errno);
+                                       perror("sendto");
+#endif DEBUG
+                               continue;

                        }
                        }

+

                        /*
                        /*

-                        * Wait for reply 
+                        * Wait for reply

                         */
                         */

-                       timeout.tv_sec = _res.retrans;
+                       timeout.tv_sec = (_res.retrans << (_res.retry - retry))
+                               / _res.nscount;
+                       if (timeout.tv_sec <= 0)
+                               timeout.tv_sec = 1;

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

-                       dsmask = 1 << s;
-                       n = select(s+1, &dsmask, 0, 0, &timeout);
+wait:
+                       FD_ZERO(&dsmask);
+                       FD_SET(s, &dsmask);
+                       n = select(s+1, &dsmask, (fd_set *)NULL,
+                               (fd_set *)NULL, &timeout);

                        if (n < 0) {
                        if (n < 0) {

+#ifdef DEBUG

                                if (_res.options & RES_DEBUG)
                                if (_res.options & RES_DEBUG)

-                                       printf("select errno = %d\n", errno);
+                                       perror("select");
+#endif DEBUG

                                continue;
                        }
                        if (n == 0) {
                                /*
                                 * timeout
                                 */
                                continue;
                        }
                        if (n == 0) {
                                /*
                                 * timeout
                                 */

+#ifdef DEBUG

                                if (_res.options & RES_DEBUG)
                                        printf("timeout\n");
                                if (_res.options & RES_DEBUG)
                                        printf("timeout\n");

+#endif DEBUG
+                               /*
+                                * Disconnect if we want to listen
+                                * for responses from more than one server.
+                                */
+                               if (_res.nscount > 1 && connected) {
+                                       (void) connect(s, &no_addr,
+                                           sizeof(no_addr));
+                                       connected = 0;
+                               }
+                               gotsomewhere = 1;

                                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)
                                if (_res.options & RES_DEBUG)

-                                       printf("recvfrom, errno=%d\n", errno);
+                                       perror("recvfrom");
+#endif DEBUG

                                continue;
                        }
                                continue;
                        }

+                       gotsomewhere = 1;

                        if (id != anhp->id) {
                                /*
                                 * response from old query, ignore it
                                 */
                        if (id != anhp->id) {
                                /*
                                 * response from old query, ignore it
                                 */

+#ifdef DEBUG

                                if (_res.options & RES_DEBUG) {
                                        printf("old answer:\n");
                                        p_query(answer);
                                }
                                if (_res.options & RES_DEBUG) {
                                        printf("old answer:\n");
                                        p_query(answer);
                                }

-                               continue;
+#endif DEBUG
+                               goto wait;

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

+#ifdef DEBUG

                                if (_res.options & RES_DEBUG)
                                        printf("truncated answer\n");
                                if (_res.options & RES_DEBUG)
                                        printf("truncated answer\n");

+#endif DEBUG

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

-                               retry = _res.retry;
+                               /*
+                                * retry decremented on continue
+                                * to desired starting value
+                                */
+                               retry = _res.retry + 1;

                                v_circuit = 1;
                                continue;
                        }
                }
                                v_circuit = 1;
                                continue;
                        }
                }

+#ifdef DEBUG

                if (_res.options & RES_DEBUG) {
                        printf("got answer:\n");
                        p_query(answer);
                }
                if (_res.options & RES_DEBUG) {
                        printf("got answer:\n");
                        p_query(answer);
                }

+#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);
+               }
+          }
+       }
+       if (s >= 0) {

                (void) close(s);
                (void) close(s);

-               return (resplen);
+               s = -1;

        }
        }

-       (void) close(s);
+       if (v_circuit == 0)
+               if (gotsomewhere == 0)
+                       errno = ECONNREFUSED;
+               else
+                       errno = ETIMEDOUT;
+       else
+               errno = terrno;

        return (-1);
 }
        return (-1);
 }

+
+/*
+ * This routine is for closing the socket if a virtual circuit is used and
+ * the program wants to close it.  This provides support for endhostent()
+ * which expects to close the socket.
+ *
+ * This routine is not expected to be user visible.
+ */
+_res_close()
+{
+       if (s != -1) {
+               (void) close(s);
+               s = -1;
+       }
+}