[NaCl SDK] nacl_io: Add support for basic socketpairs.

native_client_sdk/src/tests/nacl_io_test/socket_test.cc

Index: native_client_sdk/src/tests/nacl_io_test/socket_test.cc
diff --git a/native_client_sdk/src/tests/nacl_io_test/socket_test.cc b/native_client_sdk/src/tests/nacl_io_test/socket_test.cc
index 03d96375685ebef522042067da42e2b07fa74c6d..199513793adc20ea5f23fa520f03ad72503a429a 100644
--- a/native_client_sdk/src/tests/nacl_io_test/socket_test.cc
+++ b/native_client_sdk/src/tests/nacl_io_test/socket_test.cc
@@ -254,12 +254,17 @@ TEST_F(SocketTest, Socketpair) {
   int sv[2];
   EXPECT_LT(ki_socketpair(AF_INET, SOCK_STREAM, 0, NULL), 0);
   EXPECT_EQ(errno, EFAULT);
-  EXPECT_LT(ki_socketpair(AF_UNIX, SOCK_STREAM, 0, sv), 0);
-  EXPECT_EQ(errno, EAFNOSUPPORT);
   EXPECT_LT(ki_socketpair(AF_INET, SOCK_STREAM, 0, sv), 0);
-  EXPECT_EQ(errno, EPROTONOSUPPORT);
+  EXPECT_EQ(errno, EOPNOTSUPP);
   EXPECT_LT(ki_socketpair(AF_INET6, SOCK_STREAM, 0, sv), 0);
-  EXPECT_EQ(errno, EPROTONOSUPPORT);
+  EXPECT_EQ(errno, EOPNOTSUPP);
+
+  sv[0] = sv[1] = -1;
+  errno = 0;
+  EXPECT_EQ(ki_socketpair(AF_UNIX, SOCK_STREAM, 0, sv), 0);
+  EXPECT_EQ(errno, 0);
+  EXPECT_GE(sv[0], 0);
+  EXPECT_GE(sv[1], 0);

[Sam Clegg, 2015/09/17 09:40:39]

More testing here would be good.  Perhaps a split into several socketpair tests?
  If there is a lot of test code perhaps we can somehow share tests/code with
the TCP tests?

Oh, I just remembered that the TCP/UDP socket tests all live in the
nacl_io_socket_test suite which runs in chrome since we don't have mocks for the
socket API.  However, socketpair tests don't rely on pepper so should all be
testable under sel_ldr here in nacl_io_test.

 }
 
 TEST(SocketUtilityFunctions, Htonl) {