Clean up chaser start/stop and error handling.

Makefile.am

@@ -77,7 +77,16 @@ test_libbitcoin_node_test_SOURCES = \
     test/node.cpp \
     test/settings.cpp \
     test/test.cpp \
-    test/test.hpp
+    test/test.hpp \
+    test/chasers/chaser.cpp \
+    test/chasers/chaser_candidate.cpp \
+    test/chasers/chaser_check.cpp \
+    test/chasers/chaser_confirm.cpp \
+    test/chasers/chaser_connect.cpp \
+    test/chasers/chaser_header.cpp \
+    test/chasers/chaser_transaction.cpp \
+    test/protocols/protocol.cpp \
+    test/sessions/session.cpp
 
 endif WITH_TESTS
 

builds/cmake/CMakeLists.txt

@@ -346,7 +346,16 @@ if (with-tests)
         "../../test/node.cpp"
         "../../test/settings.cpp"
         "../../test/test.cpp"
-        "../../test/test.hpp" )
+        "../../test/test.hpp"
+        "../../test/chasers/chaser.cpp"
+        "../../test/chasers/chaser_candidate.cpp"
+        "../../test/chasers/chaser_check.cpp"
+        "../../test/chasers/chaser_confirm.cpp"
+        "../../test/chasers/chaser_connect.cpp"
+        "../../test/chasers/chaser_header.cpp"
+        "../../test/chasers/chaser_transaction.cpp"
+        "../../test/protocols/protocol.cpp"
+        "../../test/sessions/session.cpp" )
 
     add_test( NAME libbitcoin-node-test COMMAND libbitcoin-node-test
             --run_test=*

builds/msvc/vs2022/libbitcoin-node-test/libbitcoin-node-test.vcxproj

@@ -70,10 +70,19 @@
     <Import Project="$(ProjectDir)$(ProjectName).props" />
   </ImportGroup>
   <ItemGroup>
+    <ClCompile Include="..\..\..\..\test\chasers\chaser.cpp" />
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_candidate.cpp" />
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_check.cpp" />
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_confirm.cpp" />
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_connect.cpp" />
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_header.cpp" />
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_transaction.cpp" />
     <ClCompile Include="..\..\..\..\test\configuration.cpp" />
     <ClCompile Include="..\..\..\..\test\error.cpp" />
     <ClCompile Include="..\..\..\..\test\main.cpp" />
     <ClCompile Include="..\..\..\..\test\node.cpp" />
+    <ClCompile Include="..\..\..\..\test\protocols\protocol.cpp" />
+    <ClCompile Include="..\..\..\..\test\sessions\session.cpp" />
     <ClCompile Include="..\..\..\..\test\settings.cpp" />
     <ClCompile Include="..\..\..\..\test\test.cpp" />
   </ItemGroup>

builds/msvc/vs2022/libbitcoin-node-test/libbitcoin-node-test.vcxproj.filters

@@ -10,8 +10,38 @@
     <Filter Include="src">
       <UniqueIdentifier>{4BD50864-D3BC-4F64-0000-000000000000}</UniqueIdentifier>
     </Filter>
+    <Filter Include="src\chasers">
+      <UniqueIdentifier>{4BD50864-D3BC-4F64-0000-000000000001}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="src\protocols">
+      <UniqueIdentifier>{4BD50864-D3BC-4F64-0000-000000000002}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="src\sessions">
+      <UniqueIdentifier>{4BD50864-D3BC-4F64-0000-000000000003}</UniqueIdentifier>
+    </Filter>
   </ItemGroup>
   <ItemGroup>
+    <ClCompile Include="..\..\..\..\test\chasers\chaser.cpp">
+      <Filter>src\chasers</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_candidate.cpp">
+      <Filter>src\chasers</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_check.cpp">
+      <Filter>src\chasers</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_confirm.cpp">
+      <Filter>src\chasers</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_connect.cpp">
+      <Filter>src\chasers</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_header.cpp">
+      <Filter>src\chasers</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\..\..\test\chasers\chaser_transaction.cpp">
+      <Filter>src\chasers</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\..\..\test\configuration.cpp">
       <Filter>src</Filter>
     </ClCompile>
@@ -24,6 +54,12 @@
     <ClCompile Include="..\..\..\..\test\node.cpp">
       <Filter>src</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\..\..\test\protocols\protocol.cpp">
+      <Filter>src\protocols</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\..\..\test\sessions\session.cpp">
+      <Filter>src\sessions</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\..\..\test\settings.cpp">
       <Filter>src</Filter>
     </ClCompile>

include/bitcoin/node/chasers/chaser.hpp

@@ -29,7 +29,7 @@ namespace node {
 
 class full_node;
 
-/// Abstract base chaser.
+/// Abstract base chaser for thread safe chain state management classes.
 /// Chasers impose order on blockchain/pool construction as necessary.
 /// Each chaser operates on its own strand, implemented here, allowing
 /// concurrent chaser operations to the extent that threads are available.
@@ -84,7 +84,7 @@ class BCN_API chaser
     DELETE_COPY_MOVE(chaser);
 
     /// Synchronously subscribe to notify and asynchronously initialize state.
-    virtual bool start() NOEXCEPT = 0;
+    virtual code start() NOEXCEPT = 0;
 
 protected:
     chaser(full_node& node) NOEXCEPT;
@@ -99,13 +99,16 @@ class BCN_API chaser
     /// True if the current thread is on the chaser strand.
     bool stranded() const NOEXCEPT;
 
+    /// True if the current thread is on the node strand.
+    bool node_stranded() const NOEXCEPT;
+
     /// Subscribe to chaser events.
-    bool subscribe(event_handler&& handler) NOEXCEPT;
+    code subscribe(event_handler&& handler) NOEXCEPT;
 
     /// Set chaser event (does not require network strand).
     void notify(const code& ec, chase event_, link value) NOEXCEPT;
 
-    /// Close the node.
+    /// Close the node in case of failure.
     void stop(const code& ec) NOEXCEPT;
 
 private:

include/bitcoin/node/chasers/chaser_candidate.hpp

@@ -36,7 +36,7 @@ class BCN_API chaser_candidate
 public:
     chaser_candidate(full_node& node) NOEXCEPT;
 
-    virtual bool start() NOEXCEPT;
+    virtual code start() NOEXCEPT;
 
 protected:
     virtual void handle_transaction(transaction_t value) NOEXCEPT;

include/bitcoin/node/chasers/chaser_check.hpp

@@ -36,7 +36,7 @@ class BCN_API chaser_check
 public:
     chaser_check(full_node& node) NOEXCEPT;
 
-    virtual bool start() NOEXCEPT;
+    virtual code start() NOEXCEPT;
     virtual void checked(const system::chain::block::cptr& block) NOEXCEPT;
 
 protected:

include/bitcoin/node/chasers/chaser_confirm.hpp

@@ -36,7 +36,7 @@ class BCN_API chaser_confirm
 public:
     chaser_confirm(full_node& node) NOEXCEPT;
 
-    virtual bool start() NOEXCEPT;
+    virtual code start() NOEXCEPT;
 
 protected:
     virtual void handle_connected(header_t block) NOEXCEPT;

include/bitcoin/node/chasers/chaser_connect.hpp

@@ -36,7 +36,7 @@ class BCN_API chaser_connect
 public:
     chaser_connect(full_node& node) NOEXCEPT;
 
-    virtual bool start() NOEXCEPT;
+    virtual code start() NOEXCEPT;
 
 protected:
     virtual void handle_checked(header_t block) NOEXCEPT;

include/bitcoin/node/chasers/chaser_header.hpp

@@ -19,7 +19,6 @@
 #ifndef LIBBITCOIN_NODE_CHASERS_CHASER_HEADER_HPP
 #define LIBBITCOIN_NODE_CHASERS_CHASER_HEADER_HPP
 
-#include <functional>
 #include <unordered_map>
 #include <bitcoin/database.hpp>
 #include <bitcoin/network.hpp>
@@ -32,15 +31,15 @@ namespace node {
 class full_node;
 
 /// Chase down stronger header branches for the candidate chain.
-/// Weak branches are retained in a hash table unless already store populated.
+/// Weak branches are retained in a hash table if not store populated.
 /// Strong branches reorganize the candidate chain and fire the 'header' event.
 class BCN_API chaser_header
   : public chaser
 {
 public:
     chaser_header(full_node& node) NOEXCEPT;
 
-    virtual bool start() NOEXCEPT;
+    virtual code start() NOEXCEPT;
 
     /// Organize the next header in sequence, relative to caller's peer.
     /// Causes a fault/stop if preceding headers have not been stored.
@@ -49,8 +48,16 @@ class BCN_API chaser_header
         system::chain::context&& context) NOEXCEPT;
 
 protected:
+    struct proposed_header
+    {
+        database::context context;
+        system::chain::header::cptr header;
+    };
     typedef std::vector<database::header_link> header_links;
 
+    // This is protected by strand.
+    std::unordered_map<system::hash_digest, proposed_header> tree_{};
+
     /// Handlers.
     virtual void handle_event(const code& ec, chase event_,
         link value) NOEXCEPT;
@@ -82,18 +89,11 @@ class BCN_API chaser_header
     virtual bool push(const system::hash_digest& key) NOEXCEPT;
 
 private:
-    struct proposed_header
-    {
-        database::context context;
-        system::chain::header::cptr header;
-    };
-
     void do_handle_event(const code& ec, chase event_, link value) NOEXCEPT;
     void do_organize(const system::chain::header::cptr& header,
         const system::chain::context& context) NOEXCEPT;
 
-    // These are protected by strand.
-    std::unordered_map<system::hash_digest, proposed_header> tree_{};
+    // These are thread safe.
     const network::wall_clock::duration currency_window_;
     const bool use_currency_window_;
 };

include/bitcoin/node/chasers/chaser_transaction.hpp

@@ -36,7 +36,7 @@ class BCN_API chaser_transaction
 public:
     chaser_transaction(full_node& node) NOEXCEPT;
 
-    virtual bool start() NOEXCEPT;
+    code start() NOEXCEPT override;
     virtual void store(const system::chain::transaction::cptr& block) NOEXCEPT;
 
 protected:

src/chasers/chaser.cpp

@@ -58,18 +58,15 @@ bool chaser::stranded() const NOEXCEPT
     return strand_.running_in_this_thread();
 }
 
-bool chaser::subscribe(event_handler&& handler) NOEXCEPT
+bool chaser::node_stranded() const NOEXCEPT
 {
-    BC_ASSERT_MSG(node_.stranded(), "chaser");
-    const auto ec = subscriber_.subscribe(std::move(handler));
-
-    if (ec)
-    {
-        LOGF("Chaser subscribe fault, " << ec.message());
-        return false;
-    }
+    return node_.stranded();
+}
 
-    return true;
+code chaser::subscribe(event_handler&& handler) NOEXCEPT
+{
+    BC_ASSERT_MSG(node_stranded(), "chaser");
+    return subscriber_.subscribe(std::move(handler));
 }
 
 // Posts to network strand (call from chaser strands).
@@ -82,13 +79,13 @@ void chaser::notify(const code& ec, chase event_, link value) NOEXCEPT
 // Executed on network strand (handler should bounce to chaser strand).
 void chaser::do_notify(const code& ec, chase event_, link value) NOEXCEPT
 {
-    BC_ASSERT_MSG(node_.stranded(), "chaser");
+    BC_ASSERT_MSG(node_stranded(), "chaser");
     subscriber_.notify(ec, event_, value);
 }
 
-void chaser::stop(const code&) NOEXCEPT
+void chaser::stop(const code& ec) NOEXCEPT
 {
-    ////LOGF("Chaser fault, " << ec.message());
+    LOGF("Chaser fault, " << ec.message());
     node_.close();
 }
 

src/chasers/chaser_candidate.cpp

@@ -38,6 +38,14 @@ chaser_candidate::chaser_candidate(full_node& node) NOEXCEPT
 {
 }
 
+// TODO: initialize candidate state.
+code chaser_candidate::start() NOEXCEPT
+{
+    BC_ASSERT_MSG(node_stranded(), "chaser_check");
+    return subscribe(std::bind(&chaser_candidate::handle_event,
+        this, _1, _2, _3));
+}
+
 void chaser_candidate::handle_event(const code& ec, chase event_,
     link value) NOEXCEPT
 {
@@ -66,13 +74,6 @@ void chaser_candidate::do_handle_event(const code& ec, chase event_,
     }
 }
 
-// TODO: initialize candidate state.
-bool chaser_candidate::start() NOEXCEPT
-{
-    return subscribe(std::bind(&chaser_candidate::handle_event,
-        this, _1, _2, _3));
-}
-
 // TODO: handle transaction graph change (may issue 'candidate').
 void chaser_candidate::handle_transaction(transaction_t tx) NOEXCEPT
 {

src/chasers/chaser_check.cpp

@@ -39,6 +39,16 @@ chaser_check::chaser_check(full_node& node) NOEXCEPT
 {
 }
 
+// TODO: initialize check state.
+code chaser_check::start() NOEXCEPT
+{
+    BC_ASSERT_MSG(node_stranded(), "chaser_check");
+
+    // get_all_unassociated_above(0)
+    return subscribe(std::bind(&chaser_check::handle_event,
+        this, _1, _2, _3));
+}
+
 void chaser_check::handle_event(const code& ec, chase event_,
     link value) NOEXCEPT
 {
@@ -67,14 +77,6 @@ void chaser_check::do_handle_event(const code& ec, chase event_,
     }
 }
 
-// TODO: initialize check state.
-bool chaser_check::start() NOEXCEPT
-{
-    // get_all_unassociated_above(0)
-    return subscribe(std::bind(&chaser_check::handle_event,
-        this, _1, _2, _3));
-}
-
 // TODO: handle the new strong branch (may issue 'checked').
 void chaser_check::handle_header(height_t branch_point) NOEXCEPT
 {

src/chasers/chaser_confirm.cpp

@@ -37,6 +37,14 @@ chaser_confirm::chaser_confirm(full_node& node) NOEXCEPT
 {
 }
 
+// TODO: initialize confirm state.
+code chaser_confirm::start() NOEXCEPT
+{
+    BC_ASSERT_MSG(node_stranded(), "chaser_confirm");
+    return subscribe(std::bind(&chaser_confirm::handle_event,
+        this, _1, _2, _3));
+}
+
 void chaser_confirm::handle_event(const code& ec, chase event_,
     link value) NOEXCEPT
 {
@@ -65,13 +73,6 @@ void chaser_confirm::do_handle_event(const code& ec, chase event_,
     }
 }
 
-// TODO: initialize confirm state.
-bool chaser_confirm::start() NOEXCEPT
-{
-    return subscribe(std::bind(&chaser_confirm::handle_event,
-        this, _1, _2, _3));
-}
-
 // TODO: handle new strong connected branch (may issue 'confirmed').
 void chaser_confirm::handle_connected(header_t block) NOEXCEPT
 {