joystickcallback : Add new callback, add overload.

.gitignore

@@ -82,4 +82,4 @@ tests/timeout
 tests/title
 tests/triangle-vulkan
 tests/windows
-
+/[Bb]uild*/

include/GLFW/glfw3.h

@@ -1613,6 +1613,32 @@ typedef void (* GLFWmonitorfun)(GLFWmonitor*,int);
  */
 typedef void (* GLFWjoystickfun)(int,int);
 
+/*! @brief The function pointer type for window joystick configuration callbacks.
+ *
+ *  This is the function pointer type for window joystick configuration callbacks.
+ *  Even though joystick configuration callbacks are global events, you may
+ *  use this version of the callback to recieve valid window pointers in
+ *  your callback. Must be used with appropriate glfwSetJoystickCallback overload.
+ *
+ *  A joystick configuration callback function has the following signature:
+ *  @code
+ *  void function_name(GLFWwindow* window, int jid, int event)
+ *  @endcode
+ *
+ *  @param[in] window A valid window associated to the event.
+ *  @param[in] jid The joystick that was connected or disconnected.
+ *  @param[in] event One of `GLFW_CONNECTED` or `GLFW_DISCONNECTED`.  Future
+ *  releases may add more events.
+ *
+ *  @sa @ref joystick_event
+ *  @sa @ref glfwSetJoystickCallback
+ *
+ *  @since Added in version 3.4.
+ *
+ *  @ingroup input
+ */
+typedef void (* GLFWjoystickwindowfun)(GLFWwindow*,int,int);
+
 /*! @brief Video mode type.
  *
  *  This describes a single video mode.
@@ -5139,6 +5165,44 @@ GLFWAPI int glfwJoystickIsGamepad(int jid);
  */
 GLFWAPI GLFWjoystickfun glfwSetJoystickCallback(GLFWjoystickfun callback);
 
+/*! @brief Sets the window joystick configuration callback.
+ *
+ *  This function sets the window joystick configuration callback, or removes the
+ *  currently set callback.  This is called when a joystick is connected to or
+ *  disconnected from the system. Windows which have registered to recieve
+ *  this callback will be notified, and provided with their window pointer.
+ *
+ *  For joystick connection and disconnection events to be delivered on all
+ *  platforms, you need to call one of the [event processing](@ref events)
+ *  functions.  Joystick disconnection may also be detected and the callback
+ *  called by joystick functions.  The function will then return whatever it
+ *  returns if the joystick is not present.
+ *
+ *  @param[in] window The window whose callback to set.
+ *  @param[in] callback The new callback, or `NULL` to remove the currently set
+ *  callback.
+ *  @return The previously set callback, or `NULL` if no callback was set or the
+ *  library had not been [initialized](@ref intro_init).
+ *
+ *  @callback_signature
+ *  @code
+ *  void function_name(GLFWwindow* window, int jid, int event)
+ *  @endcode
+ *  For more information about the callback parameters, see the
+ *  [function pointer type](@ref GLFWjoystickwindowfun).
+ *
+ *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED.
+ *
+ *  @thread_safety This function must only be called from the main thread.
+ *
+ *  @sa @ref joystick_event
+ *
+ *  @since Added in version 3.4.
+ *
+ *  @ingroup input
+ */
+GLFWAPI GLFWjoystickwindowfun glfwSetJoystickCallback(GLFWwindow* window, GLFWjoystickwindowfun callback);
+
 /*! @brief Adds the specified SDL_GameControllerDB gamepad mappings.
  *
  *  This function parses the specified ASCII encoded string and updates the

src/input.c

@@ -373,6 +373,18 @@ void _glfwInputJoystick(_GLFWjoystick* js, int event)
 
     if (_glfw.callbacks.joystick)
         _glfw.callbacks.joystick(jid, event);
+
+    // Send event to windows that want the notification.
+    {
+        _GLFWwindow* window;
+
+        for (window = _glfw.windowListHead;  window;  window = window->next) {
+            GLFWjoystickwindowfun fun = window->callbacks.joystickConnect;
+            if (fun) {
+                fun((GLFWwindow*) window, jid, event);
+            }
+        }
+    }
 }
 
 // Notifies shared code of the new value of a joystick axis
@@ -1112,6 +1124,16 @@ GLFWAPI GLFWjoystickfun glfwSetJoystickCallback(GLFWjoystickfun cbfun)
     return cbfun;
 }
 
+GLFWAPI GLFWjoystickwindowfun glfwSetJoystickCallback(GLFWwindow* handle, GLFWjoystickwindowfun cbfun)
+{
+    _GLFWwindow* window = (_GLFWwindow*) handle;
+    assert(window != NULL);
+
+    _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
+    _GLFW_SWAP_POINTERS(window->callbacks.joystickConnect, cbfun);
+    return cbfun;
+}
+
 GLFWAPI int glfwUpdateGamepadMappings(const char* string)
 {
     int jid;

src/internal.h

@@ -412,6 +412,7 @@ struct _GLFWwindow
         GLFWcharfun             character;
         GLFWcharmodsfun         charmods;
         GLFWdropfun             drop;
+        GLFWjoystickwindowfun   joystickConnect;
     } callbacks;
 
     // This is defined in the window API's platform.h