start rewriting ASIO-related network service implementation

net/asio/adc_netservice_asio.h

@@ -5,6 +5,7 @@
 #include <asio/basic_stream_socket.hpp>
 #include <asio/bind_executor.hpp>
 #include <asio/compose.hpp>
+#include <asio/deferred.hpp>
 #include <asio/ip/tcp.hpp>
 #include <asio/ip/udp.hpp>
 #include <asio/local/seq_packet_protocol.hpp>
@@ -13,6 +14,7 @@
 #include <asio/steady_timer.hpp>
 #include <asio/strand.hpp>
 #include <asio/streambuf.hpp>
+#include <asio/use_awaitable.hpp>
 #include <asio/use_future.hpp>
 #include <asio/write.hpp>
 
@@ -48,6 +50,26 @@ concept adc_asio_stream_transport_proto_c =
     std::derived_from<T, asio::ip::tcp> || std::derived_from<T, asio::local::stream_protocol>;
 
 
+template <typename T>
+concept adc_asio_is_future = requires {
+    []<typename AllocatorT>(std::type_identity<asio::use_future_t<AllocatorT>>) {
+    }(std::type_identity<std::remove_cvref_t<T>>());
+};
+
+template <typename T>
+concept adc_asio_is_awaitable = requires {
+    []<typename ExecutorT>(std::type_identity<asio::use_awaitable_t<ExecutorT>>) {
+    }(std::type_identity<std::remove_cvref_t<T>>());
+};
+
+struct adc_asio_async_call_ctx_t {
+};
+
+template <typename T>
+concept adc_completion_token_c = traits::adc_is_callable<T> || std::same_as<T, adc_asio_async_call_ctx_t> ||
+                                 std::same_as<T, asio::deferred_t> || adc_asio_is_future<T> || adc_asio_is_awaitable<T>;
+
+
 template <adc_asio_transport_proto_c TRANSPORT_PROTOT,
           interfaces::adc_netsession_proto_c<std::string_view> SESSION_PROTOT,
           traits::adc_output_char_range RMSGT = std::vector<char>>
@@ -67,6 +89,9 @@ public:
         std::function<void(std::error_code, RMSGT)> receive_comp_token;
     };
 
+    // to satisfy 'adc_netservice_c' concept
+    using async_call_ctx_t = adc_asio_async_call_ctx_t;
+
     static constexpr std::chrono::duration DEFAULT_ACCEPT_TIMEOUT = std::chrono::years::max();
     static constexpr std::chrono::duration DEFAULT_CONNECT_TIMEOUT = std::chrono::seconds(10);
     static constexpr std::chrono::duration DEFAULT_SEND_TIMEOUT = std::chrono::seconds(5);
@@ -81,7 +106,10 @@ public:
     virtual ~AdcNetServiceASIOBase() {}
 
 
-    netservice_ident_t ident() const { return _ident; }
+    netservice_ident_t ident() const
+    {
+        return _ident;
+    }
 
 
     void clear()
@@ -92,39 +120,31 @@ public:
     }
 
 
-    template <traits::adc_time_duration_c TimeoutT = decltype(DEFAULT_CONNECT_TIMEOUT)>
-    auto asyncConnect(const endpoint_t& endpoint,
-                      asio_async_ctx_t& ctx,
-                      const TimeoutT& timeout = DEFAULT_CONNECT_TIMEOUT)
+    template <adc_completion_token_c TokenT, traits::adc_time_duration_c TimeoutT = decltype(DEFAULT_CONNECT_TIMEOUT)>
+    auto asyncConnect(const endpoint_t& endpoint, TokenT&& token, const TimeoutT& timeout = DEFAULT_CONNECT_TIMEOUT)
     {
+        static_assert(std::is_same_v<TokenT, async_call_ctx_t>, "'async_call_ctx_t'-TYPE MUST NOT BE USED!");
+
         auto timer = getDeadlineTimer(timeout);
 
-        auto comp_token = [&ctx, timer = std::move(timer), this](std::error_code ec) {
+        auto comp_token = [wrapper = traits::adc_pf_wrapper(std::forward<TokenT>(token)),
+                           timer = std::move(timer)](std::error_code ec) {
             if (isTimeout(timer, ec)) {
                 ec = std::make_error_code(std::errc::timed_out);
             } else {
                 timer->cancel();
             }
-            if (!ctx.use_future) {
-                ctx.connect_comp_token(ec);
+
+            if constexpr (!adc_asio_is_future<TokenT>) {
+                std::get<0>(wrapper)(ec);
             }
         };
 
-        if (ctx.use_future) {
-            comp_token = asio::use_future(comp_token);
+        if constexpr (!adc_asio_is_future<TokenT>) {
+            return _socket.async_connect(endpoint, asio::use_future(std::move(comp_token)));
+        } else {
+            return _socket.async_connect(endpoint, std::move(comp_token));
         }
-
-        return _socket.async_connect(endpoint, comp_token);
-
-        // if (ctx.use_future) {
-        //     return _socket.async_connect(
-        //         endpoint, asio::use_future([&ctx, timer = std::move(timer)](std::error_code) { timer->cancel(); }));
-        // } else {
-        //     return _socket.async_connect(endpoint, [&ctx, timer = std::move(timer)](std::error_code ec) {
-        //         timer->cancel();
-        //         ctx.connect_comp_token(ec);
-        //     });
-        // }
     }
 
 
@@ -170,7 +190,7 @@ public:
 
         auto timer = getDeadlineTimer(timeout);
 
-        auto comp_token = [&ctx, timer = std::move(timer)](std::error_code ec, size_t) {
+        auto comp_token = [&ctx, buff_seq, timer = std::move(timer)](std::error_code ec, size_t) {
             timer->cancel();
 
             if (!ctx.use_future) {
@@ -364,9 +384,15 @@ public:
         return ftr.get();
     }
 
-    void setShutdownType(asio::socket_base::shutdown_type shutdown_type) { _shutdownType = shutdown_type; }
+    void setShutdownType(asio::socket_base::shutdown_type shutdown_type)
+    {
+        _shutdownType = shutdown_type;
+    }
 
-    asio::socket_base::shutdown_type getShutdownType() const { return _shutdownType; }
+    asio::socket_base::shutdown_type getShutdownType() const
+    {
+        return _shutdownType;
+    }
 
     std::error_code close()
     {
@@ -415,7 +441,7 @@ protected:
     }
 
     template <typename TimerT>
-    bool isTimeout(const std::unique_ptr<TimerT>& timer, const std::error_code& ec)
+    static bool isTimeout(const std::unique_ptr<TimerT>& timer, const std::error_code& ec)
     {
         auto exp_time = timer->expiry();
         return (exp_time < std::chrono::steady_clock::now()) && (ec == asio::error::operation_aborted);