Move internals to shared joystick objects

Preparation for gamecontrollerdb support and the gamepad API.

src/input.c

@@ -30,6 +30,7 @@
 #include <assert.h>
 #include <float.h>
 #include <stdlib.h>
+#include <string.h>
 
 // Internal key state used for sticky keys
 #define _GLFW_STICK 3
@@ -123,12 +124,22 @@ void _glfwInputDrop(_GLFWwindow* window, int count, const char** paths)
         window->callbacks.drop((GLFWwindow*) window, count, paths);
 }
 
-void _glfwInputJoystickChange(int jid, int event)
+void _glfwInputJoystick(int jid, int event)
 {
     if (_glfw.callbacks.joystick)
         _glfw.callbacks.joystick(jid, event);
 }
 
+void _glfwInputJoystickAxis(int jid, int axis, float value)
+{
+    _glfw.joysticks[jid].axes[axis] = value;
+}
+
+void _glfwInputJoystickButton(int jid, int button, char value)
+{
+    _glfw.joysticks[jid].buttons[button] = value;
+}
+
 
 //////////////////////////////////////////////////////////////////////////
 //////                       GLFW internal API                      //////
@@ -141,6 +152,39 @@ GLFWbool _glfwIsPrintable(int key)
            key == GLFW_KEY_KP_EQUAL;
 }
 
+_GLFWjoystick* _glfwAllocJoystick(const char* name, int axisCount, int buttonCount)
+{
+    int jid;
+    _GLFWjoystick* js;
+
+    for (jid = 0;  jid <= GLFW_JOYSTICK_LAST;  jid++)
+    {
+        if (!_glfw.joysticks[jid].present)
+            break;
+    }
+
+    if (jid > GLFW_JOYSTICK_LAST)
+        return NULL;
+
+    js = _glfw.joysticks + jid;
+    js->present     = GLFW_TRUE;
+    js->name        = strdup(name);
+    js->axes        = calloc(axisCount, sizeof(float));
+    js->buttons     = calloc(buttonCount, 1);
+    js->axisCount   = axisCount;
+    js->buttonCount = buttonCount;
+
+    return js;
+}
+
+void _glfwFreeJoystick(_GLFWjoystick* js)
+{
+    free(js->name);
+    free(js->axes);
+    free(js->buttons);
+    memset(js, 0, sizeof(_GLFWjoystick));
+}
+
 
 //////////////////////////////////////////////////////////////////////////
 //////                        GLFW public API                       //////
@@ -554,20 +598,29 @@ GLFWAPI GLFWdropfun glfwSetDropCallback(GLFWwindow* handle, GLFWdropfun cbfun)
 
 GLFWAPI int glfwJoystickPresent(int jid)
 {
-    _GLFW_REQUIRE_INIT_OR_RETURN(0);
+    assert(jid >= GLFW_JOYSTICK_1);
+    assert(jid <= GLFW_JOYSTICK_LAST);
+
+    _GLFW_REQUIRE_INIT_OR_RETURN(GLFW_FALSE);
 
     if (jid < 0 || jid > GLFW_JOYSTICK_LAST)
     {
         _glfwInputError(GLFW_INVALID_ENUM, "Invalid joystick %i", jid);
-        return 0;
+        return GLFW_FALSE;
     }
 
-    return _glfwPlatformJoystickPresent(jid);
+    if (!_glfw.joysticks[jid].present)
+        return GLFW_FALSE;
+
+    return _glfwPlatformPollJoystick(jid, _GLFW_POLL_PRESENCE);
 }
 
 GLFWAPI const float* glfwGetJoystickAxes(int jid, int* count)
 {
+    assert(jid >= GLFW_JOYSTICK_1);
+    assert(jid <= GLFW_JOYSTICK_LAST);
     assert(count != NULL);
+
     *count = 0;
 
     _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
@@ -578,12 +631,22 @@ GLFWAPI const float* glfwGetJoystickAxes(int jid, int* count)
         return NULL;
     }
 
-    return _glfwPlatformGetJoystickAxes(jid, count);
+    if (!_glfw.joysticks[jid].present)
+        return NULL;
+
+    if (!_glfwPlatformPollJoystick(jid, _GLFW_POLL_AXES))
+        return NULL;
+
+    *count = _glfw.joysticks[jid].axisCount;
+    return _glfw.joysticks[jid].axes;
 }
 
 GLFWAPI const unsigned char* glfwGetJoystickButtons(int jid, int* count)
 {
+    assert(jid >= GLFW_JOYSTICK_1);
+    assert(jid <= GLFW_JOYSTICK_LAST);
     assert(count != NULL);
+
     *count = 0;
 
     _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
@@ -594,11 +657,21 @@ GLFWAPI const unsigned char* glfwGetJoystickButtons(int jid, int* count)
         return NULL;
     }
 
-    return _glfwPlatformGetJoystickButtons(jid, count);
+    if (!_glfw.joysticks[jid].present)
+        return NULL;
+
+    if (!_glfwPlatformPollJoystick(jid, _GLFW_POLL_BUTTONS))
+        return NULL;
+
+    *count = _glfw.joysticks[jid].buttonCount;
+    return _glfw.joysticks[jid].buttons;
 }
 
 GLFWAPI const char* glfwGetJoystickName(int jid)
 {
+    assert(jid >= GLFW_JOYSTICK_1);
+    assert(jid <= GLFW_JOYSTICK_LAST);
+
     _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
 
     if (jid < 0 || jid > GLFW_JOYSTICK_LAST)
@@ -607,7 +680,13 @@ GLFWAPI const char* glfwGetJoystickName(int jid)
         return NULL;
     }
 
-    return _glfwPlatformGetJoystickName(jid);
+    if (!_glfw.joysticks[jid].present)
+        return NULL;
+
+    if (!_glfwPlatformPollJoystick(jid, _GLFW_POLL_PRESENCE))
+        return NULL;
+
+    return _glfw.joysticks[jid].name;
 }
 
 GLFWAPI GLFWjoystickfun glfwSetJoystickCallback(GLFWjoystickfun cbfun)