socketpair: an implemention for Windows and more

Curl_socketpair() is designed to be used and work everywhere if there's
no native version or the native version isn't good enough.

Closes #4466

1 files changed, 36 insertions, 0 deletions

diff --git a/lib/socketpair.h b/lib/socketpair.h
new file mode 100644
index 000000000..be9fb24f9
--- /dev/null
+++ b/lib/socketpair.h
@@ -0,0 +1,36 @@
+#ifndef HEADER_CURL_SOCKETPAIR_H
+#define HEADER_CURL_SOCKETPAIR_H
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+#ifndef HAVE_SOCKETPAIR
+int Curl_socketpair(int domain, int type, int protocol,
+                    curl_socket_t socks[2]);
+#else
+#define Curl_socketpair(a,b,c,d) socketpair(a,b,c,d)
+#endif
+
+/* Defined here to allow specific build configs to disable it completely */
+#define USE_SOCKETPAIR 1
+
+#endif /* HEADER_CURL_SOCKETPAIR_H */