server: Refactor to make the event loop owned by server object

Source/cmServer.h

@@ -7,26 +7,83 @@
 #include "cm_jsoncpp_value.h"
 #include "cm_uv.h"
 
+#include <memory> // IWYU pragma: keep
 #include <string>
 #include <vector>
 
+class cmConnection;
 class cmFileMonitor;
-class cmServerConnection;
 class cmServerProtocol;
 class cmServerRequest;
 class cmServerResponse;
 
-class cmServer
+/***
+ * This essentially hold and manages a libuv event queue and responds to
+ * messages
+ * on any of its connections.
+ */
+class cmServerBase
+{
+public:
+  cmServerBase(cmConnection* connection);
+  virtual ~cmServerBase();
+
+  virtual void AddNewConnection(cmConnection* ownedConnection);
+
+  /***
+   * The main override responsible for tailoring behavior towards
+   * whatever the given server is supposed to do
+   *
+   * This should almost always be called by the given connections
+   * directly.
+   *
+   * @param connection The connectiont the request was received on
+   * @param request The actual request
+   */
+  virtual void ProcessRequest(cmConnection* connection,
+                              const std::string& request) = 0;
+  virtual void OnConnected(cmConnection* connection);
+  virtual void OnDisconnect();
+
+  /***
+   * Start a dedicated thread. If this is used to start the server, it will
+   * join on the
+   * servers dtor.
+   */
+  virtual bool StartServeThread();
+  virtual bool Serve(std::string* errorMessage);
+
+  virtual void OnServeStart();
+  virtual void StartShutDown();
+
+  virtual bool OnSignal(int signum);
+  uv_loop_t* GetLoop();
+
+  void OnDisconnect(cmConnection* pConnection);
+
+protected:
+  std::vector<std::unique_ptr<cmConnection> > Connections;
+
+  bool ServeThreadRunning = false;
+  uv_thread_t ServeThread;
+
+  uv_loop_t Loop;
+
+  uv_signal_t SIGINTHandler;
+  uv_signal_t SIGHUPHandler;
+};
+
+class cmServer : public cmServerBase
 {
   CM_DISABLE_COPY(cmServer)
 
 public:
   class DebugInfo;
 
-  cmServer(cmServerConnection* conn, bool supportExperimental);
-  ~cmServer();
+  cmServer(cmConnection* conn, bool supportExperimental);
+  ~cmServer() override;
 
-  bool Serve(std::string* errorMessage);
+  bool Serve(std::string* errorMessage) override;
 
   cmFileMonitor* FileMonitor() const;
 
@@ -34,9 +91,20 @@ private:
   void RegisterProtocol(cmServerProtocol* protocol);
 
   // Callbacks from cmServerConnection:
-  void PopOne();
-  void QueueRequest(const std::string& request);
 
+  void ProcessRequest(cmConnection* connection,
+                      const std::string& request) override;
+  std::shared_ptr<cmFileMonitor> fileMonitor;
+
+public:
+  void OnServeStart() override;
+
+  void StartShutDown() override;
+
+public:
+  void OnConnected(cmConnection* connection) override;
+
+private:
   static void reportProgress(const char* msg, float progress, void* data);
   static void reportMessage(const char* msg, const char* title, bool& cancel,
                             void* data);
@@ -44,36 +112,37 @@ private:
   // Handle requests:
   cmServerResponse SetProtocolVersion(const cmServerRequest& request);
 
-  void PrintHello() const;
+  void PrintHello(cmConnection* connection) const;
 
   // Write responses:
   void WriteProgress(const cmServerRequest& request, int min, int current,
                      int max, const std::string& message) const;
   void WriteMessage(const cmServerRequest& request, const std::string& message,
                     const std::string& title) const;
-  void WriteResponse(const cmServerResponse& response,
+  void WriteResponse(cmConnection* connection,
+                     const cmServerResponse& response,
                      const DebugInfo* debug) const;
-  void WriteParseError(const std::string& message) const;
+  void WriteParseError(cmConnection* connection,
+                       const std::string& message) const;
   void WriteSignal(const std::string& name, const Json::Value& obj) const;
 
   void WriteJsonObject(Json::Value const& jsonValue,
                        const DebugInfo* debug) const;
 
+  void WriteJsonObject(cmConnection* connection, Json::Value const& jsonValue,
+                       const DebugInfo* debug) const;
+
   static cmServerProtocol* FindMatchingProtocol(
     const std::vector<cmServerProtocol*>& protocols, int major, int minor);
 
-  cmServerConnection* Connection = nullptr;
   const bool SupportExperimental;
 
   cmServerProtocol* Protocol = nullptr;
   std::vector<cmServerProtocol*> SupportedProtocols;
-  std::vector<std::string> Queue;
 
   std::string DataBuffer;
   std::string JsonData;
 
-  uv_loop_t* Loop = nullptr;
-
   typedef union
   {
     uv_tty_t tty;
@@ -87,7 +156,6 @@ private:
 
   mutable bool Writing = false;
 
-  friend class cmServerConnection;
   friend class cmServerProtocol;
   friend class cmServerRequest;
 };