refactor background thread into a separate .cpp file

dll/dll/steam_client.h

@@ -64,6 +64,35 @@ enum Steam_Pipe {
     SERVER
 };
 
+class Steam_Client;
+class Client_Background_Thread
+{
+private:
+    // don't run immediately, give the game some time to initialize
+    constexpr const static auto initial_delay = std::chrono::seconds(2);
+    // max allowed time in which RunCallbacks() might not be called
+    constexpr const static auto max_stall_ms = std::chrono::milliseconds(300);
+
+    std::thread background_keepalive{};
+    std::mutex kill_background_thread_mutex{};
+    std::condition_variable kill_background_thread_cv{};
+    bool kill_background_thread{};
+    
+    Steam_Client *client_instance{};
+    
+    void thread_proc();
+
+public:
+    Client_Background_Thread();
+    ~Client_Background_Thread();
+
+    // spawn the thread if necessary, never call this inside the ctor of Steam_Client
+    // since the thread will attempt to get the global client pointer during initialization (which will still be under construction)
+    void start(Steam_Client *client_instance);
+    // kill the thread if necessary
+    void kill();
+};
+
 class Steam_Client :
 public ISteamClient007,
 public ISteamClient008,
@@ -144,14 +173,14 @@ public:
     Steam_Masterserver_Updater *steam_masterserver_updater{};
     Steam_AppTicket *steam_app_ticket{};
 
+    Client_Background_Thread *background_thread{};
+
     Steam_Overlay* steam_overlay{};
 
     bool steamclient_server_inited = false;
 
     bool gameserver_has_ipv6_functions{};
     
-    std::thread background_keepalive{};
-
     unsigned steam_pipe_counter = 1;
     std::map<HSteamPipe, enum Steam_Pipe> steam_pipes{};
 

dll/steam_client.cpp

@@ -19,60 +19,13 @@
 #include "dll/settings_parser.h"
 
 
-static std::mutex kill_background_thread_mutex{};
-static std::condition_variable kill_background_thread_cv{};
-static bool kill_background_thread{};
-static void background_thread(Steam_Client *client)
-{
-    // max allowed time in which RunCallbacks() might not be called
-    constexpr const static auto max_stall_ms = std::chrono::milliseconds(300);
-
-    // wait 1 sec
-    {
-        std::unique_lock<std::mutex> lck(kill_background_thread_mutex);
-        if (kill_background_thread || kill_background_thread_cv.wait_for(lck, std::chrono::seconds(1)) != std::cv_status::timeout) {
-            if (kill_background_thread) {
-                PRINT_DEBUG("early exit");
-                return;
-            }
-        }
-    }
-
-    PRINT_DEBUG("starting");
-
-    while (1) {
-        {
-            std::unique_lock lck(kill_background_thread_mutex);
-            if (kill_background_thread || kill_background_thread_cv.wait_for(lck, max_stall_ms) != std::cv_status::timeout) {
-                if (kill_background_thread) {
-                    PRINT_DEBUG("exit");
-                    return;
-                }
-            }
-        }
-
-        auto now_ms = (unsigned long long)std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::steady_clock::now().time_since_epoch()).count();
-
-        // if our time exceeds last run time of callbacks and it wasn't processing already
-        if (!client->cb_run_active && (now_ms >= (client->last_cb_run + max_stall_ms.count()))) {
-            global_mutex.lock();
-            PRINT_DEBUG("run @@@@@@@@@@@@@@@@@@@@@@@@@@@");
-            client->last_cb_run = now_ms; // update the time counter just to avoid overlap
-            client->network->Run(); // networking must run first since it receives messages used by each run_callback()
-            client->run_every_runcb->run(); // call each run_callback()
-            global_mutex.unlock();
-        }
-    }
-}
-
-
-
 Steam_Client::Steam_Client()
 {
     PRINT_DEBUG("start ----------");
     uint32 appid = create_localstorage_settings(&settings_client, &settings_server, &local_storage);
     local_storage->update_save_filenames(Local_Storage::remote_storage_folder);
 
+    background_thread = new Client_Background_Thread();
     network = new Networking(settings_server->get_local_steam_id(), appid, settings_server->get_port(), &(settings_server->custom_broadcasts), settings_server->disable_networking);
 
     run_every_runcb = new RunEveryRunCB();
@@ -333,17 +286,14 @@ HSteamUser Steam_Client::ConnectToGlobalUser( HSteamPipe hSteamPipe )
 
     userLogIn();
     
-    
     // games like appid 1740720 and 2379780 do not call SteamAPI_RunCallbacks() or SteamAPI_ManualDispatch_RunFrame() or Steam_BGetCallback()
     // hence all run_callbacks() will never run, which might break the assumption that these callbacks are always run
     // also networking callbacks won't run
     // hence we spawn the background thread here which trigger all run_callbacks() and run networking callbacks
-    if (!background_keepalive.joinable()) {
+    background_thread->start(this);
-        background_keepalive = std::thread(background_thread, this);
-        PRINT_DEBUG("spawned background thread *********");
-    }
 
     steam_overlay->SetupOverlay();
+    
     steam_pipes[hSteamPipe] = Steam_Pipe::CLIENT;
     return CLIENT_HSTEAMUSER;
 }
@@ -427,21 +377,8 @@ bool Steam_Client::BShutdownIfAllPipesClosed()
     PRINT_DEBUG_ENTRY();
     if (steam_pipes.size()) return false; // not all pipes are released via BReleaseSteamPipe() yet
     
-    bool joinable = background_keepalive.joinable();
+    background_thread->kill();
-    if (joinable) {
-        {
-            std::lock_guard lk(kill_background_thread_mutex);
-            kill_background_thread = true;
-        }
-        kill_background_thread_cv.notify_one();
-    }
-
     steam_controller->Shutdown();
-
-
-    if (joinable) {
-        background_keepalive.join();
-    }
     steam_overlay->UnSetupOverlay();
 
     PRINT_DEBUG("all pipes closed");

dll/steam_client_background_thread.cpp

@@ -0,0 +1,90 @@
+/* Copyright (C) 2019 Mr Goldberg
+   This file is part of the Goldberg Emulator
+
+   The Goldberg Emulator is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   The Goldberg Emulator is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the Goldberg Emulator; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "dll/steam_client.h"
+#include "dll/dll.h"
+
+void Client_Background_Thread::thread_proc()
+{
+    // wait for some time
+    {
+
+        std::unique_lock lck(kill_background_thread_mutex);
+        if (kill_background_thread_cv.wait_for(lck, initial_delay, [&] { return kill_background_thread; })) {
+            PRINT_DEBUG("early exit");
+            return;
+        }
+    }
+
+    PRINT_DEBUG("starting");
+
+    while (1) {
+        {
+            std::unique_lock lck(kill_background_thread_mutex);
+            if (kill_background_thread_cv.wait_for(lck, max_stall_ms, [&] { return kill_background_thread; })) {
+                PRINT_DEBUG("exit");
+                return;
+            }
+        }
+
+        auto now_ms = (unsigned long long)std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::steady_clock::now().time_since_epoch()).count();
+
+        // if our time exceeds last run time of callbacks and it wasn't processing already
+        const auto runcallbacks_timeout_ms = client_instance->get_last_runcallbacks_time() + max_stall_ms.count();
+        if (!client_instance->runcallbacks_active() && (now_ms >= runcallbacks_timeout_ms)) {
+            std::lock_guard lock(global_mutex);
+            PRINT_DEBUG("run @@@@@@@@@@@@@@@@@@@@@@@@@@@");
+            client_instance->set_last_runcallbacks_time(now_ms); // update the time counter just to avoid overlap
+            client_instance->network->Run(); // networking must run first since it receives messages used by each run_callback()
+            client_instance->run_every_runcb->run(); // call each run_callback()
+        }
+    }
+}
+
+
+Client_Background_Thread::Client_Background_Thread()
+{
+
+}
+
+Client_Background_Thread::~Client_Background_Thread()
+{
+    kill();
+}
+
+void Client_Background_Thread::start(Steam_Client *client_instance)
+{
+    if (background_keepalive.joinable()) return; // alrady spawned
+    
+    this->client_instance = client_instance;
+    background_keepalive = std::thread([this] { thread_proc(); });
+    PRINT_DEBUG("spawned background thread *********");
+}
+
+void Client_Background_Thread::kill()
+{
+    if (!background_keepalive.joinable()) return; // already killed
+    
+    {
+        std::lock_guard lk(kill_background_thread_mutex);
+        kill_background_thread = true;
+    }
+    kill_background_thread_cv.notify_one();
+    PRINT_DEBUG("joining worker thread");
+    background_keepalive.join();
+    PRINT_DEBUG("worker thread killed");
+}