socket-util: Move sock_errno() to socket-util.

And add more users.

Signed-off-by: Gurucharan Shetty <gshetty@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>

lib/socket-util.h

@@ -17,6 +17,7 @@
 #ifndef SOCKET_UTIL_H
 #define SOCKET_UTIL_H 1
 
+#include <errno.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/time.h>
@@ -99,4 +100,15 @@ static inline int rpl_setsockopt(int sock, int level, int optname,
 }
 #endif
 
+/* In Windows platform, errno is not set for socket calls.
+ * The last error has to be gotten from WSAGetLastError(). */
+static inline int sock_errno(void)
+{
+#ifdef _WIN32
+    return WSAGetLastError();
+#else
+    return errno;
+#endif
+}
+
 #endif /* socket-util.h */