[src/trunk]: src/tests/lib/libc/sys Handle ENOBUFS when receiving messages.

[roy <roy%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/678af3591942
branches:  trunk
changeset: 321540:678af3591942
user:      roy <roy%NetBSD.org@localhost>
date:      Wed Mar 21 12:37:12 2018 +0000

description:
Handle ENOBUFS when receiving messages.
Don't send messages if the receiver has died.

diffstat:

 tests/lib/libc/sys/t_recvmmsg.c |  40 ++++++++++++++++++++++++++++++++++------
 1 files changed, 34 insertions(+), 6 deletions(-)

diffs (104 lines):

diff -r 14c84a119116 -r 678af3591942 tests/lib/libc/sys/t_recvmmsg.c
--- a/tests/lib/libc/sys/t_recvmmsg.c   Wed Mar 21 10:21:17 2018 +0000
+++ b/tests/lib/libc/sys/t_recvmmsg.c   Wed Mar 21 12:37:12 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: t_recvmmsg.c,v 1.1 2012/06/22 18:45:23 christos Exp $  */
+/*     $NetBSD: t_recvmmsg.c,v 1.2 2018/03/21 12:37:12 roy Exp $       */
 
 /*-
  * Copyright (c) 2012 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: t_recvmmsg.c,v 1.1 2012/06/22 18:45:23 christos Exp $");
+__RCSID("$NetBSD: t_recvmmsg.c,v 1.2 2018/03/21 12:37:12 roy Exp $");
 
 #include <atf-c.h>
 #include <sys/types.h>
@@ -47,6 +47,7 @@
 #include <time.h>
 #include <stdint.h>
 #include <errno.h>
+#include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
@@ -57,7 +58,14 @@
 
 #define min(a, b) ((a) < (b) ? (a) : (b))
 static int debug;
+static volatile sig_atomic_t rdied;
 
+static void
+handle_sigchld(__unused int pid)
+{
+
+       rdied = 1;
+}
 
 ATF_TC(recvmmsg_basic);
 ATF_TC_HEAD(recvmmsg_basic, tc)
@@ -75,7 +83,9 @@
        int status;
        off_t off;
        uint8_t DGRAM[1316] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, };
-       
+       struct sigaction sa;
+       ssize_t overf = 0;
+
        error = socketpair(AF_UNIX, SOCK_DGRAM, 0, fd);
        ATF_REQUIRE_MSG(error != -1, "socketpair failed (%s)", strerror(errno));
 
@@ -98,6 +108,14 @@
                mmsghdr[n].msg_hdr.msg_namelen = 0;
        }
 
+       memset(&sa, 0, sizeof(sa));
+       sa.sa_flags = SA_RESTART;
+       sa.sa_handler = &handle_sigchld;
+       sigemptyset(&sa.sa_mask);
+       error = sigaction(SIGCHLD, &sa, 0);
+       ATF_REQUIRE_MSG(error != -1, "sigaction failed (%s)",
+           strerror(errno));
+
        switch (fork()) {
        case -1:
                ATF_REQUIRE_MSG(0, "fork failed (%s)", strerror(errno));
@@ -112,6 +130,13 @@
                        struct timespec ts = { 1, 0 };
                        cnt = recvmmsg(fd[1], mmsghdr, min(mmsgcnt, n),
                            MSG_WAITALL, &ts);
+                       if (cnt == -1 && errno == ENOBUFS) {
+                               overf++;
+                               if (debug)
+                                       printf("receive buffer overflowed"
+                                           " (%zu)\n",overf);
+                               continue;
+                       }
                        ATF_REQUIRE_MSG(cnt != -1, "recvmmsg failed (%s)",
                            strerror(errno));
                        ATF_REQUIRE_MSG(cnt != 0, "recvmmsg timeout");
@@ -138,16 +163,19 @@
                                printf("sending packet %u/%u...\n", (n+1),
                                    NPKTS);
                        do {
+                               if (rdied)
+                                       break;
                                DGRAM[0] = n;
                                error = send(fd[0], DGRAM, sizeof(DGRAM), 0);
                        } while (error == -1 && errno == ENOBUFS);
-                       if (error == -1)
-                               ATF_REQUIRE_MSG(error != -1, "send failed (%s)",
-                                   strerror(errno));
+                       ATF_REQUIRE_MSG(error != -1, "send failed (%s)",
+                           strerror(errno));
                }
                error = wait(&status);
                ATF_REQUIRE_MSG(error != -1, "wait failed (%s)",
                    strerror(errno));
+               ATF_REQUIRE_MSG(WIFEXITED(status) && WEXITSTATUS(status) == 0,
+                   "receiver died");
                break;
        }
 }