From 59d309c7b5860e1e795156ceb902f6b4dbf4ed61 Mon Sep 17 00:00:00 2001
From: Vitaly Buka <vitalybuka@google.com>
Date: Mon, 10 Apr 2017 17:59:07 +0000
Subject: [PATCH] [msan] Make test to fall-back to IPv6 if IPv4 is not
 available.

Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31896

llvm-svn: 299862
---
 compiler-rt/test/msan/Linux/sendmsg.cc | 31 ++++++++++++++++++++++---------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/compiler-rt/test/msan/Linux/sendmsg.cc b/compiler-rt/test/msan/Linux/sendmsg.cc
index 6a8ef83..4fc6c88 100644
--- a/compiler-rt/test/msan/Linux/sendmsg.cc
+++ b/compiler-rt/test/msan/Linux/sendmsg.cc
@@ -33,17 +33,31 @@ int main() {
   char buf[kBufSize] = {0};
   pthread_t client_thread;
   struct sockaddr_in serveraddr;
-
-  sockfd = socket(AF_INET, SOCK_DGRAM, 0);
+  struct sockaddr_in6 serveraddr6;
 
   memset(&serveraddr, 0, sizeof(serveraddr));
   serveraddr.sin_family = AF_INET;
   serveraddr.sin_addr.s_addr = htonl(INADDR_ANY);
   serveraddr.sin_port = 0;
-
-  bind(sockfd, (struct sockaddr *)&serveraddr, sizeof(serveraddr));
+  struct sockaddr *addr = (struct sockaddr *)&serveraddr;
   socklen_t addrlen = sizeof(serveraddr);
-  getsockname(sockfd, (struct sockaddr *)&serveraddr, &addrlen);
+
+  sockfd = socket(addr->sa_family, SOCK_DGRAM, 0);
+  if (sockfd <= 0) {
+    // Try to fall-back to IPv6
+    memset(&serveraddr6, 0, sizeof(serveraddr6));
+    serveraddr6.sin6_family = AF_INET6;
+    serveraddr6.sin6_addr = in6addr_any;
+    serveraddr6.sin6_port = 0;
+    addr = (struct sockaddr *)&serveraddr6;
+    addrlen = sizeof(serveraddr6);
+
+    sockfd = socket(addr->sa_family, SOCK_DGRAM, 0);
+  }
+  assert(sockfd > 0);
+
+  bind(sockfd, addr, addrlen);
+  getsockname(sockfd, addr, &addrlen);
 
 #if defined(POISON)
   __msan_poison(buf + 7, 1);
@@ -52,7 +66,7 @@ int main() {
 #if defined(SENDMSG)
   struct iovec iov[2] = {{buf, 5}, {buf + 5, 5}};
   struct msghdr msg;
-  msg.msg_name = &serveraddr;
+  msg.msg_name = addr;
   msg.msg_namelen = addrlen;
   msg.msg_iov = iov;
   msg.msg_iovlen = 2;
@@ -62,14 +76,13 @@ int main() {
 #endif
 
 #if defined(SEND)
-  ret = connect(sockfd, (struct sockaddr *)&serveraddr, addrlen);
+  ret = connect(sockfd, addr, addrlen);
   assert(ret == 0);
   ret = send(sockfd, buf, kBufSize, 0);
   // SEND: Uninitialized bytes in __interceptor_send at offset 7 inside [{{.*}}, 10)
   assert(ret > 0);
 #elif defined(SENDTO)
-  ret =
-      sendto(sockfd, buf, kBufSize, 0, (struct sockaddr *)&serveraddr, addrlen);
+  ret = sendto(sockfd, buf, kBufSize, 0, addr, addrlen);
   // SENDTO: Uninitialized bytes in __interceptor_sendto at offset 7 inside [{{.*}}, 10)
   assert(ret > 0);
 #elif defined(SENDMSG)
-- 
2.7.4