include pipe2/socketpair compat for macOS

include/compat/sys/socket.h

@@ -8,3 +8,10 @@
 #else
 #include <win32netcompat.h>
 #endif
+
+#if !defined(SOCK_NONBLOCK) || !defined(SOCK_CLOEXEC)
+#define SOCK_CLOEXEC            0x8000  /* set FD_CLOEXEC */
+#define SOCK_NONBLOCK           0x4000  /* set O_NONBLOCK */
+int bsd_socketpair(int domain, int type, int protocol, int socket_vector[2]);
+#define socketpair(d,t,p,sv) bsd_socketpair(d,t,p,sv)
+#endif

include/compat/unistd.h

@@ -40,4 +40,8 @@ int getentropy(void *buf, size_t buflen);
 
 #define pledge(request, paths) 0
 
+#ifndef HAVE_PIPE2
+int pipe2(int fildes[2], int flags);
+#endif
+
 #endif