[Qemu-devel] [PATCH] sockets: Fix test for DragonFly BSD

[Antonio Huete Jiménez]

From f57cdc7ec2d5a5e906fa8b795eeede2d7b66aa56 Mon Sep 17 00:00:00 2001
From: Antonio Huete Jimenez <tuxi...@quantumachine.net>
Date: Fri, 15 Dec 2017 01:08:10 +0100
Subject: [PATCH] sockets: Fix test for DragonFly BSD
DragonFly BSD does not implement AI_V4MAPPED for its getaddrinfo() so
probe and discard that flag instead of aborting the test.

Test that fails:
    ERROR:tests/test-char.c:448:char_udp_test_internal: 'chr' should  
not be NULL

Signed-off-by: Antonio Huete Jimenez <tuxi...@quantumachine.net>
---
 util/qemu-sockets.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c
index af4f01211a..5a9c55c303 100644
--- a/util/qemu-sockets.c
+++ b/util/qemu-sockets.c
@@ -43,6 +43,8 @@
 # define AI_NUMERICSERV 0
 #endif

+int useV4Mapped = 1;
+

 static int inet_getport(struct addrinfo *e)
 {
@@ -383,7 +385,6 @@ static struct addrinfo  
*inet_parse_connect_saddr(InetSocketAddress *saddr,
     struct addrinfo ai, *res;
     int rc;
     Error *err = NULL;
-    static int useV4Mapped = 1;

     memset(&ai, 0, sizeof(ai));

@@ -474,7 +475,11 @@ static int inet_dgram_saddr(InetSocketAddress *sraddr,

     /* lookup peer addr */
     memset(&ai,0, sizeof(ai));
-    ai.ai_flags = AI_CANONNAME | AI_V4MAPPED | AI_ADDRCONFIG;
+    ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
+    if (atomic_read(&useV4Mapped)) {
+        ai.ai_flags |= AI_V4MAPPED;
+    }
+
     ai.ai_family = inet_ai_family_from_address(sraddr, &err);
     ai.ai_socktype = SOCK_DGRAM;

@@ -493,7 +498,21 @@ static int inet_dgram_saddr(InetSocketAddress *sraddr,
         goto err;
     }

-    if ((rc = getaddrinfo(addr, port, &ai, &peer)) != 0) {
+    /* lookup */
+    rc = getaddrinfo(addr, port, &ai, &peer);
+
+    /* At least FreeBSD and OS-X 10.6 declare AI_V4MAPPED but
+     * then don't implement it in their getaddrinfo(). Detect
+     * this and retry without the flag since that's preferrable
+     * to a fatal error
+     */
+    if (rc == EAI_BADFLAGS &&
+        (ai.ai_flags & AI_V4MAPPED)) {
+        atomic_set(&useV4Mapped, 0);
+        ai.ai_flags &= ~AI_V4MAPPED;
+        rc = getaddrinfo(addr, port, &ai, &peer);
+    }
+    if (rc != 0) {
         error_setg(errp, "address resolution failed for %s:%s: %s",  
addr, port,
                    gai_strerror(rc));
         goto err;
--
2.15.0