malloc fd_set dynamically, for very large fd uses

1 files changed, 13 insertions, 6 deletions

diff --git a/src/lib/libc/net/res_send.c b/src/lib/libc/net/res_send.c
index bfc01f9b6a..284f85d7fe 100644
--- a/src/lib/libc/net/res_send.c
+++ b/src/lib/libc/net/res_send.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: res_send.c,v 1.4 1997/03/13 19:07:41 downsj Exp $     */
+/*      $OpenBSD: res_send.c,v 1.5 1997/05/28 21:38:57 deraadt Exp $    */
 
 /*
  * ++Copyright++ 1985, 1989, 1993
@@ -60,7 +60,7 @@
 static char sccsid[] = "@(#)res_send.c  8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$From: res_send.c,v 8.12 1996/10/08 04:51:06 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_send.c,v 1.4 1997/03/13 19:07:41 downsj Exp $";
+static char rcsid[] = "$OpenBSD: res_send.c,v 1.5 1997/05/28 21:38:57 deraadt Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -489,7 +489,7 @@ read_len:
                          * Use datagrams.
                          */
                         struct timeval timeout;
-                        fd_set dsmask;
+                        fd_set *dsmaskp;
                         struct sockaddr_in from;
                         int fromlen;
 
@@ -595,10 +595,17 @@ read_len:
                                 timeout.tv_sec = 1;
                         timeout.tv_usec = 0;
     wait:
-                        FD_ZERO(&dsmask);
-                        FD_SET(s, &dsmask);
-                        n = select(s+1, &dsmask, (fd_set *)NULL,
+                        dsmaskp = (fd_set *)malloc(howmany(s, NFDBITS) *
+                                sizeof(fd_mask));
+                        if (dsmaskp == NULL) {
+                                res_close();
+                                goto next_ns;
+                        }
+                        FD_ZERO(dsmaskp);
+                        FD_SET(s, dsmaskp);
+                        n = select(s+1, dsmaskp, (fd_set *)NULL,
                                    (fd_set *)NULL, &timeout);
+                        free(dsmaskp);
                         if (n < 0) {
                                 if (errno == EINTR)
                                         goto wait;