Client or Server Tag Selector

deanberris · deanberris · commit 00b27b7a4843 · 2010-11-28T09:49:19.000+08:00
This change introduces a selector metafunction that takes a tag, and
checks whether it is meant to be a client or server tag. The selector
metafunction then yields the actual tag found (whether it is a client or
server tag) so that it can be used for function tag dispatch purposes.
diff --git a/boost/network/protocol/http/support/client_or_server.hpp b/boost/network/protocol/http/support/client_or_server.hpp
@@ -0,0 +1,35 @@
+#ifndef BOOST_NETWORK_PROTOCOL_HTTP_SUPPORT_CLIENT_OR_SERVER_HPP_20101127
+#define BOOST_NETWORK_PROTOCOL_HTTP_SUPPORT_CLIENT_OR_SERVER_HPP_20101127
+
+// Copyright 2010 Dean Michael Berris. 
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+#include <boost/network/protocol/http/support/is_server.hpp>
+#include <boost/network/protocol/http/support/is_client.hpp>
+#include <boost/mpl/if.hpp>
+
+namespace boost { namespace network { namespace http {
+
+    template <class Tag>
+    struct client_or_server :
+        mpl::if_<
+            is_server<Tag>,
+            tags::server,
+            typename mpl::if_<
+                is_client<Tag>,
+                tags::client,
+                unsupported_tag<Tag>
+                >::type
+            >
+    {};
+
+    
+} /* http */
+    
+} /* network */
+    
+} /* boost */
+
+#endif /* BOOST_NETWORK_PROTOCOL_HTTP_SUPPORT_CLIENT_OR_SERVER_HPP_20101127 */
diff --git a/boost/network/protocol/http/support/is_client.hpp b/boost/network/protocol/http/support/is_client.hpp
@@ -0,0 +1,29 @@
+#ifndef BOOST_NETWORK_PROTOCOL_SUPPORT_IS_CLIENT_HPP_20101118
+#define BOOST_NETWORK_PROTOCOL_SUPPORT_IS_CLIENT_HPP_20101118
+
+// Copyright 2010 Dean Michael Berris. 
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+#include <boost/network/protocol/http/tags.hpp>
+#include <boost/type_traits/is_base_of.hpp>
+
+namespace boost { namespace network { namespace http {
+
+    template <class Tag>
+    struct is_client : 
+        is_base_of<
+            tags::client,
+            Tag
+        >
+    {};
+    
+} /* http */
+    
+} /* network */
+    
+} /* boost */
+
+#endif /* BOOST_NETWORK_PROTOCOL_SUPPORT_IS_CLIENT_HPP_20101118 */
+
diff --git a/boost/network/protocol/http/tags.hpp b/boost/network/protocol/http/tags.hpp
@@ -14,18 +14,19 @@ namespace boost { namespace network { namespace http { namespace tags {
     struct keepalive {};
     struct simple {};
     struct server {};
+    struct client {};
 
     using namespace boost::network::tags;
 
     template <class Tag>
     struct components;
     
-    typedef mpl::vector<http, simple, sync, tcp, default_string> http_default_8bit_tcp_resolve_tags;
-    typedef mpl::vector<http, simple, sync, udp, default_string> http_default_8bit_udp_resolve_tags;
-    typedef mpl::vector<http, keepalive, sync, tcp, default_string> http_keepalive_8bit_tcp_resolve_tags;
-    typedef mpl::vector<http, keepalive, sync, udp, default_string> http_keepalive_8bit_udp_resolve_tags;
-    typedef mpl::vector<http, simple, async, udp, default_string> http_async_8bit_udp_resolve_tags;
-    typedef mpl::vector<http, simple, async, tcp, default_string> http_async_8bit_tcp_resolve_tags;
+    typedef mpl::vector<http, client, simple, sync, tcp, default_string> http_default_8bit_tcp_resolve_tags;
+    typedef mpl::vector<http, client, simple, sync, udp, default_string> http_default_8bit_udp_resolve_tags;
+    typedef mpl::vector<http, client, keepalive, sync, tcp, default_string> http_keepalive_8bit_tcp_resolve_tags;
+    typedef mpl::vector<http, client, keepalive, sync, udp, default_string> http_keepalive_8bit_udp_resolve_tags;
+    typedef mpl::vector<http, client, simple, async, udp, default_string> http_async_8bit_udp_resolve_tags;
+    typedef mpl::vector<http, client, simple, async, tcp, default_string> http_async_8bit_tcp_resolve_tags;
     typedef mpl::vector<http, simple, sync, pod, default_string, server> http_server_tags;
     typedef mpl::vector<http, simple, async, pod, default_string, server> http_async_server_tags;
 
