Merge pull request libbitcoin#391 from evoskuil/master

Add service suspension, tests.

include/bitcoin/network/error.hpp

@@ -116,6 +116,7 @@ enum error_t : uint8_t
     channel_inactive,
     channel_stopped,
     service_stopped,
+    service_suspended,
     subscriber_exists,
     subscriber_stopped,
     desubscribed

include/bitcoin/network/net/acceptor.hpp

@@ -19,6 +19,7 @@
 #ifndef LIBBITCOIN_NETWORK_NET_ACCEPTOR_HPP
 #define LIBBITCOIN_NETWORK_NET_ACCEPTOR_HPP
 
+#include <atomic>
 #include <functional>
 #include <memory>
 #include <bitcoin/system.hpp>
@@ -49,7 +50,8 @@ class BCT_API acceptor
 
     /// Construct an instance.
     acceptor(const logger& log, asio::strand& strand,
-        asio::io_context& service, const settings& settings) NOEXCEPT;
+        asio::io_context& service, const settings& settings,
+        std::atomic_bool& suspended) NOEXCEPT;
 
     /// Asserts/logs stopped.
     virtual ~acceptor() NOEXCEPT;
@@ -88,6 +90,7 @@ class BCT_API acceptor
     const settings& settings_;
     asio::io_context& service_;
     asio::strand& strand_;
+    std::atomic_bool& suspended_;
 
     // These are protected by strand.
     asio::acceptor acceptor_;

include/bitcoin/network/net/connector.hpp

@@ -19,6 +19,7 @@
 #ifndef LIBBITCOIN_NETWORK_NET_CONNECTOR_HPP
 #define LIBBITCOIN_NETWORK_NET_CONNECTOR_HPP
 
+#include <atomic>
 #include <memory>
 #include <bitcoin/system.hpp>
 #include <bitcoin/network/async/async.hpp>
@@ -51,7 +52,8 @@ class BCT_API connector
 
     /// Construct an instance.
     connector(const logger& log, asio::strand& strand,
-        asio::io_context& service, const settings& settings) NOEXCEPT;
+        asio::io_context& service, const settings& settings,
+        std::atomic_bool& suspended) NOEXCEPT;
 
     /// Asserts/logs stopped.
     virtual ~connector() NOEXCEPT;
@@ -90,6 +92,7 @@ class BCT_API connector
     const settings& settings_;
     asio::io_context& service_;
     asio::strand& strand_;
+    std::atomic_bool& suspended_;
 
     // These are protected by strand.
     asio::resolver resolver_;

include/bitcoin/network/p2p.hpp

@@ -109,6 +109,13 @@ class BCT_API p2p
     virtual void connect(const config::endpoint& endpoint,
         channel_notifier&& handler) NOEXCEPT;
 
+    /// Suspensions.
+    /// -----------------------------------------------------------------------
+
+    /// Suspend/resume all connections.
+    virtual void suspend() NOEXCEPT;
+    virtual void resume() NOEXCEPT;
+
     /// Properties.
     /// -----------------------------------------------------------------------
 
@@ -198,6 +205,12 @@ class BCT_API p2p
     virtual acceptor::ptr create_acceptor() NOEXCEPT;
     virtual connector::ptr create_connector() NOEXCEPT;
 
+    /// Suspend/resume inbound/outbound connections.
+    virtual void suspend_acceptors() NOEXCEPT;
+    virtual void resume_acceptors() NOEXCEPT;
+    virtual void suspend_connectors() NOEXCEPT;
+    virtual void resume_connectors() NOEXCEPT;
+
     /// Register nonces for loopback (true implies found), require strand.
     virtual bool store_nonce(const channel& channel) NOEXCEPT;
     virtual bool unstore_nonce(const channel& channel) NOEXCEPT;
@@ -252,6 +265,8 @@ class BCT_API p2p
     // These are thread safe.
     const settings& settings_;
     std::atomic_bool closed_{ false };
+    std::atomic_bool accept_suspended_{ false };
+    std::atomic_bool connect_suspended_{ false };
     std::atomic<size_t> total_channel_count_{};
     std::atomic<size_t> inbound_channel_count_{};
 

include/bitcoin/network/sessions/session_outbound.hpp

@@ -65,7 +65,8 @@ class BCT_API session_outbound
     void do_one(const code& ec, const config::address& peer, object_key key,
         const race::ptr& racer, const connector::ptr& connector) NOEXCEPT;
     void handle_one(const code& ec, const socket::ptr& socket,
-        object_key key, const race::ptr& racer) NOEXCEPT;
+        object_key key, const config::address& peer,
+        const race::ptr& racer) NOEXCEPT;
     void handle_connect(const code& ec, const socket::ptr& socket,
         object_key key) NOEXCEPT;
 

src/error.cpp

@@ -92,6 +92,7 @@ DEFINE_ERROR_T_MESSAGE_MAP(error)
     { channel_inactive, "channel inactive" },
     { channel_stopped, "channel stopped" },
     { service_stopped, "service stopped" },
+    { service_suspended, "service suspended" },
     { subscriber_exists, "subscriber exists" },
     { subscriber_stopped, "subscriber stopped" },
     { desubscribed, "subscriber desubscribed" }

src/net/acceptor.cpp

@@ -18,6 +18,7 @@
  */
 #include <bitcoin/network/net/acceptor.hpp>
 
+#include <atomic>
 #include <functional>
 #include <memory>
 #include <utility>
@@ -49,10 +50,12 @@ inline asio::endpoint make_endpoint(bool enable_ipv6, uint16_t port) NOEXCEPT
 // Calls are stranded to protect the acceptor member.
 
 acceptor::acceptor(const logger& log, asio::strand& strand,
-    asio::io_context& service, const settings& settings) NOEXCEPT
+    asio::io_context& service, const settings& settings,
+    std::atomic_bool& suspended) NOEXCEPT
   : settings_(settings),
     service_(service),
     strand_(strand),
+    suspended_(suspended),
     acceptor_(strand_),
     reporter(log),
     tracker<acceptor>(log)
@@ -150,6 +153,12 @@ void acceptor::accept(socket_handler&& handler) NOEXCEPT
         return;
     }
 
+    if (suspended_.load())
+    {
+        handler(error::service_suspended, nullptr);
+        return;
+    }
+
     // Create the socket.
     const auto socket = std::make_shared<network::socket>(log, service_);
 
@@ -173,6 +182,13 @@ void acceptor::handle_accept(const code& ec, const socket::ptr& socket,
         return;
     }
 
+    if (suspended_.load())
+    {
+        socket->stop();
+        handler(error::service_suspended, nullptr);
+        return;
+    }
+
     if (stopped_)
     {
         socket->stop();

src/net/connector.cpp

@@ -18,6 +18,7 @@
  */
 #include <bitcoin/network/net/connector.hpp>
 
+#include <atomic>
 #include <functional>
 #include <memory>
 #include <utility>
@@ -43,10 +44,12 @@ using namespace std::placeholders;
 // ----------------------------------------------------------------------------
 
 connector::connector(const logger& log, asio::strand& strand,
-    asio::io_context& service, const settings& settings) NOEXCEPT
+    asio::io_context& service, const settings& settings,
+    std::atomic_bool& suspended) NOEXCEPT
   : settings_(settings),
     service_(service),
     strand_(strand),
+    suspended_(suspended),
     resolver_(strand),
     timer_(std::make_shared<deadline>(log, strand, settings.connect_timeout())),
     reporter(log),
@@ -106,6 +109,12 @@ void connector::start(const std::string& hostname, uint16_t port,
         return;
     }
 
+    if (suspended_.load())
+    {
+        handler(error::service_suspended, nullptr);
+        return;
+    }
+
     // Capture the handler.
     racer_.start(std::move(handler));
 
@@ -139,6 +148,14 @@ void connector::handle_resolve(const error::boost_code& ec,
         return;
     }
 
+    if (suspended_.load())
+    {
+        timer_->stop();
+        socket->stop();
+        racer_.finish(error::service_suspended, nullptr);
+        return;
+    }
+
     // Failure in resolve, it wins (with resolve failure).
     if (ec)
     {
@@ -179,6 +196,14 @@ void connector::handle_connect(const code& ec, const finish_ptr& finish,
         return;
     }
 
+    if (suspended_.load())
+    {
+        socket->stop();
+        timer_->stop();
+        racer_.finish(error::service_suspended, nullptr);
+        return;
+    }
+
     // Failure in connect, connector wins (with connect failure).
     if (ec)
     {

src/p2p.cpp

@@ -65,13 +65,13 @@ p2p::~p2p() NOEXCEPT
 acceptor::ptr p2p::create_acceptor() NOEXCEPT
 {
     return std::make_shared<acceptor>(log, strand(), service(),
-        network_settings());
+        network_settings(), accept_suspended_);
 }
 
 connector::ptr p2p::create_connector() NOEXCEPT
 {
     return std::make_shared<connector>(log, strand(), service(),
-        network_settings());
+        network_settings(), connect_suspended_);
 }
 
 connectors_ptr p2p::create_connectors(size_t count) NOEXCEPT
@@ -372,6 +372,41 @@ void p2p::do_connect_handled(const config::endpoint& endpoint,
         handler(error::service_stopped, nullptr);
 }
 
+// Suspensions.
+// ----------------------------------------------------------------------------
+
+void p2p::suspend_acceptors() NOEXCEPT
+{
+    accept_suspended_.store(true);
+}
+
+void p2p::resume_acceptors() NOEXCEPT
+{
+    accept_suspended_.store(false);
+}
+
+void p2p::suspend_connectors() NOEXCEPT
+{
+    connect_suspended_.store(true);
+}
+
+void p2p::resume_connectors() NOEXCEPT
+{
+    connect_suspended_.store(false);
+}
+
+void p2p::suspend() NOEXCEPT
+{
+    suspend_acceptors();
+    suspend_connectors();
+}
+
+void p2p::resume() NOEXCEPT
+{
+    resume_acceptors();
+    resume_connectors();
+}
+
 // Properties.
 // ----------------------------------------------------------------------------
 

src/sessions/session_inbound.cpp

@@ -132,6 +132,13 @@ void session_inbound::handle_accept(const code& ec,
         return;
     }
 
+    if (ec == error::service_suspended)
+    {
+        ////LOGS("Suspended inbound channel start.");
+        defer(BIND(start_accept, _1, acceptor));
+        return;
+    }
+
     // There was an error accepting the channel, so try again after delay.
     if (ec)
     {

src/sessions/session_manual.cpp

@@ -130,6 +130,13 @@ void session_manual::handle_connect(const code& ec, const socket::ptr& socket,
         return;
     }
 
+    if (ec == error::service_suspended)
+    {
+        ////LOGS("Suspended manual channel start [" << peer << "].");
+        defer(BIND(start_connect, _1, peer, connector, handler));
+        return;
+    }
+
     // There was an error connecting the channel, so try again after delay.
     if (ec)
     {

src/sessions/session_outbound.cpp

@@ -98,6 +98,7 @@ void session_outbound::handle_started(const code& ec,
     LOG_ONLY(const auto batch = settings().connect_batch_size;)
     LOGN("Create " << peers << " connections " << batch << " at a time.");
 
+    // There is currently no way to vary the number of connections at runtime.
     for (size_t peer = 0; peer < peers; ++peer)
         start_connect(error::success);
 
@@ -164,16 +165,20 @@ void session_outbound::do_one(const code& ec, const config::address& peer,
         return;
     }
 
-    connector->connect(peer, BIND(handle_one, _1, _2, key, racer));
+    connector->connect(peer, BIND(handle_one, _1, _2, key, peer, racer));
 }
 
 // Handle each do_one connection attempt, stopping on first success.
 void session_outbound::handle_one(const code& ec, const socket::ptr& socket,
-    object_key key, const race::ptr& racer) NOEXCEPT
+    object_key key, const config::address& peer,
+    const race::ptr& racer) NOEXCEPT
 {
     BC_ASSERT_MSG(stranded(), "strand");
     ////COUNT(events::outbound2, key);
 
+    if (ec == error::service_suspended)
+        restore(peer, BIND(handle_reclaim, _1));
+
     // Winner in quality race is first to pass success.
     if (racer->finish(ec, socket))
     {
@@ -210,6 +215,13 @@ void session_outbound::handle_connect(const code& ec,
         return;
     }
 
+    if (ec == error::service_suspended)
+    {
+        ////LOGS("Suspended outbound channel start.");
+        defer(BIND(start_connect, _1));
+        return;
+    }
+
     // There was an error connecting a channel, so try again after delay.
     if (ec)
     {

test/error.cpp

@@ -437,6 +437,15 @@ BOOST_AUTO_TEST_CASE(error_t__code__service_stopped__true_exected_message)
     BOOST_REQUIRE_EQUAL(ec.message(), "service stopped");
 }
 
+BOOST_AUTO_TEST_CASE(error_t__code__service_suspended__true_exected_message)
+{
+    constexpr auto value = error::service_suspended;
+    const auto ec = code(value);
+    BOOST_REQUIRE(ec);
+    BOOST_REQUIRE(ec == value);
+    BOOST_REQUIRE_EQUAL(ec.message(), "service suspended");
+}
+
 BOOST_AUTO_TEST_CASE(error_t__code__subscriber_exists__true_exected_message)
 {
     constexpr auto value = error::subscriber_exists;