Cleanups in the joystick code.

Removed some redundant state and other confusions.

Fixes Bugzilla #2738.

src/joystick/SDL_joystick.c

@@ -206,10 +206,6 @@ SDL_PrivateJoystickValid(SDL_Joystick * joystick)
         valid = 1;
     }
 
-    if (joystick && joystick->closed) {
-        valid = 0;
-    }
-
     return valid;
 }
 
@@ -412,6 +408,7 @@ SDL_JoystickClose(SDL_Joystick * joystick)
     }
 
     SDL_SYS_JoystickClose(joystick);
+    joystick->hwdata = NULL;
 
     joysticklist = SDL_joysticks;
     joysticklistprev = NULL;
@@ -668,7 +665,7 @@ SDL_JoystickUpdate(void)
 
         SDL_SYS_JoystickUpdate(joystick);
 
-        if (joystick->closed && joystick->uncentered) {
+        if (joystick->force_recentering) {
             int i;
 
             /* Tell the app that everything is centered/unpressed...  */
@@ -681,7 +678,7 @@ SDL_JoystickUpdate(void)
             for (i = 0; i < joystick->nhats; i++)
                 SDL_PrivateJoystickHat(joystick, i, SDL_HAT_CENTERED);
 
-            joystick->uncentered = SDL_FALSE;
+            joystick->force_recentering = SDL_FALSE;
         }
 
         SDL_updating_joystick = NULL;

src/joystick/SDL_sysjoystick.h

@@ -53,8 +53,7 @@ struct _SDL_Joystick
 
     int ref_count;              /* Reference count for multiple opens */
 
-    SDL_bool closed;            /* SDL_TRUE if this device is no longer valid */
-    SDL_bool uncentered;        /* SDL_TRUE if this device needs to have its state reset to 0 */
+    SDL_bool force_recentering; /* SDL_TRUE if this device needs to have its state reset to 0 */
     struct _SDL_Joystick *next; /* pointer to next joystick we have allocated */
 };
 

src/joystick/android/SDL_sysjoystick.c

@@ -498,7 +498,7 @@ SDL_SYS_JoystickOpen(SDL_Joystick * joystick, int device_index)
 /* Function to determine is this joystick is attached to the system right now */
 SDL_bool SDL_SYS_JoystickAttached(SDL_Joystick *joystick)
 {
-    return !joystick->closed && (joystick->hwdata != NULL);
+    return joystick->hwdata != NULL;
 }
 
 void
@@ -529,11 +529,6 @@ SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
 void
 SDL_SYS_JoystickClose(SDL_Joystick * joystick)
 {
-    if (joystick->hwdata) {
-        ((SDL_joylist_item*)joystick->hwdata)->joystick = NULL;
-        joystick->hwdata = NULL;
-    }
-    joystick->closed = 1;
 }
 
 /* Function to perform any system-specific joystick related cleanup */

src/joystick/bsd/SDL_sysjoystick.c

@@ -558,8 +558,6 @@ SDL_SYS_JoystickClose(SDL_Joystick * joy)
     close(joy->hwdata->fd);
     SDL_free(joy->hwdata->path);
     SDL_free(joy->hwdata);
-
-    return;
 }
 
 void

src/joystick/darwin/SDL_sysjoystick.c

@@ -138,7 +138,7 @@ static void
 JoystickDeviceWasRemovedCallback(void *ctx, IOReturn result, void *sender)
 {
     recDevice *device = (recDevice *) ctx;
-    device->removed = 1;
+    device->removed = SDL_TRUE;
     device->deviceRef = NULL; // deviceRef was invalidated due to the remove
 #if SDL_HAPTIC_IOKIT
     MacHaptic_MaybeRemoveDevice(device->ffservice);
@@ -677,16 +677,7 @@ SDL_SYS_JoystickOpen(SDL_Joystick * joystick, int device_index)
 SDL_bool
 SDL_SYS_JoystickAttached(SDL_Joystick * joystick)
 {
-    recDevice *device = gpDeviceList;
-
-    while (device) {
-        if (joystick->instance_id == device->instance_id) {
-            return SDL_TRUE;
-        }
-        device = device->pNext;
-    }
-
-    return SDL_FALSE;
+    return joystick->hwdata != NULL;
 }
 
 /* Function to update the state of a joystick - called as a device poll.
@@ -707,9 +698,10 @@ SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
     }
 
     if (device->removed) {      /* device was unplugged; ignore it. */
-        joystick->closed = 1;
-        joystick->uncentered = 1;
+        if (joystick->hwdata) {
+            joystick->force_recentering = SDL_TRUE;
             joystick->hwdata = NULL;
+        }
         return;
     }
 
@@ -797,7 +789,6 @@ SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
 void
 SDL_SYS_JoystickClose(SDL_Joystick * joystick)
 {
-    joystick->closed = 1;
 }
 
 /* Function to perform any system-specific joystick related cleanup */

src/joystick/darwin/SDL_sysjoystick_c.h

@@ -58,8 +58,7 @@ struct joystick_hwdata
     recElement *firstButton;
     recElement *firstHat;
 
-    int removed;
-    int uncentered;
+    SDL_bool removed;
 
     int instance_id;
     SDL_JoystickGUID guid;

src/joystick/dummy/SDL_sysjoystick.c

@@ -34,7 +34,7 @@
 int
 SDL_SYS_JoystickInit(void)
 {
-    return (0);
+    return 0;
 }
 
 int SDL_SYS_NumJoysticks()
@@ -85,21 +85,18 @@ SDL_bool SDL_SYS_JoystickAttached(SDL_Joystick *joystick)
 void
 SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
 {
-    return;
 }
 
 /* Function to close a joystick after use */
 void
 SDL_SYS_JoystickClose(SDL_Joystick * joystick)
 {
-    return;
 }
 
 /* Function to perform any system-specific joystick related cleanup */
 void
 SDL_SYS_JoystickQuit(void)
 {
-    return;
 }
 
 SDL_JoystickGUID SDL_SYS_JoystickGetDeviceGUID( int device_index )

src/joystick/emscripten/SDL_sysjoystick.c

@@ -326,7 +326,7 @@ SDL_SYS_JoystickOpen(SDL_Joystick * joystick, int device_index)
 /* Function to determine is this joystick is attached to the system right now */
 SDL_bool SDL_SYS_JoystickAttached(SDL_Joystick *joystick)
 {
-    return !joystick->closed && (joystick->hwdata != NULL);
+    return joystick->hwdata != NULL;
 }
 
 /* Function to update the state of a joystick - called as a device poll.
@@ -378,11 +378,6 @@ SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
 void
 SDL_SYS_JoystickClose(SDL_Joystick * joystick)
 {
-    if (joystick->hwdata) {
-        ((SDL_joylist_item*)joystick->hwdata)->joystick = NULL;
-        joystick->hwdata = NULL;
-    }
-    joystick->closed = 1;
 }
 
 /* Function to perform any system-specific joystick related cleanup */

src/joystick/haiku/SDL_haikujoystick.cc

@@ -228,7 +228,6 @@ extern "C"
             SDL_free(joystick->hwdata->new_hats);
             SDL_free(joystick->hwdata->new_axes);
             SDL_free(joystick->hwdata);
-            joystick->hwdata = NULL;
         }
     }
 

src/joystick/iphoneos/SDL_sysjoystick.m

@@ -153,7 +153,6 @@ void
 SDL_SYS_JoystickClose(SDL_Joystick * joystick)
 {
     [motionManager stopAccelerometerUpdates];
-    joystick->closed = 1;
 }
 
 /* Function to perform any system-specific joystick related cleanup */

src/joystick/linux/SDL_sysjoystick.c

@@ -624,7 +624,7 @@ SDL_SYS_JoystickOpen(SDL_Joystick * joystick, int device_index)
 /* Function to determine is this joystick is attached to the system right now */
 SDL_bool SDL_SYS_JoystickAttached(SDL_Joystick *joystick)
 {
-    return !joystick->closed && (joystick->hwdata->item != NULL);
+    return joystick->hwdata->item != NULL;
 }
 
 static SDL_INLINE void
@@ -841,9 +841,7 @@ SDL_SYS_JoystickClose(SDL_Joystick * joystick)
         SDL_free(joystick->hwdata->balls);
         SDL_free(joystick->hwdata->fname);
         SDL_free(joystick->hwdata);
-        joystick->hwdata = NULL;
     }
-    joystick->closed = 1;
 }
 
 /* Function to perform any system-specific joystick related cleanup */

src/joystick/psp/SDL_sysjoystick.c

@@ -233,7 +233,6 @@ void SDL_SYS_JoystickUpdate(SDL_Joystick *joystick)
 /* Function to close a joystick after use */
 void SDL_SYS_JoystickClose(SDL_Joystick *joystick)
 {
-    /* Do nothing. */
 }
 
 /* Function to perform any system-specific joystick related cleanup */

src/joystick/windows/SDL_mmjoystick.c

@@ -383,9 +383,7 @@ SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
 void
 SDL_SYS_JoystickClose(SDL_Joystick * joystick)
 {
-    /* free system specific hardware data */
     SDL_free(joystick->hwdata);
-    joystick->hwdata = NULL;
 }
 
 /* Function to perform any system-specific joystick related cleanup */

src/joystick/windows/SDL_windowsjoystick.c

@@ -460,7 +460,6 @@ SDL_SYS_JoystickOpen(SDL_Joystick * joystick, int device_index)
 
     /* allocate memory for system specific hardware data */
     joystick->instance_id = joystickdevice->nInstanceID;
-    joystick->closed = SDL_FALSE;
     joystick->hwdata =
         (struct joystick_hwdata *) SDL_malloc(sizeof(struct joystick_hwdata));
     if (joystick->hwdata == NULL) {
@@ -480,13 +479,13 @@ SDL_SYS_JoystickOpen(SDL_Joystick * joystick, int device_index)
 SDL_bool 
 SDL_SYS_JoystickAttached(SDL_Joystick * joystick)
 {
-    return !joystick->closed && !joystick->hwdata->removed;
+    return joystick->hwdata && !joystick->hwdata->removed;
 }
 
 void
 SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
 {
-    if (joystick->closed || !joystick->hwdata) {
+    if (!joystick->hwdata || joystick->hwdata->removed) {
         return;
     }
 
@@ -497,8 +496,7 @@ SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
     }
 
     if (joystick->hwdata->removed) {
-        joystick->closed = SDL_TRUE;
-        joystick->uncentered = SDL_TRUE;
+        joystick->force_recentering = SDL_TRUE;
     }
 }
 
@@ -512,10 +510,7 @@ SDL_SYS_JoystickClose(SDL_Joystick * joystick)
         SDL_DINPUT_JoystickClose(joystick);
     }
 
-    /* free system specific hardware data */
     SDL_free(joystick->hwdata);
-
-    joystick->closed = SDL_TRUE;
 }
 
 /* Function to perform any system-specific joystick related cleanup */

test/testjoystick.c

@@ -56,6 +56,12 @@ loop(void *arg)
 
         while (SDL_PollEvent(&event)) {
             switch (event.type) {
+
+            case SDL_JOYDEVICEREMOVED:
+                SDL_Log("Joystick device %d removed.\n", (int) event.jdevice.which);
+                SDL_Log("Our instance ID is %d\n", (int) SDL_JoystickInstanceID(joystick));
+                break;
+
             case SDL_JOYAXISMOTION:
                 SDL_Log("Joystick %d axis %d value: %d\n",
                        event.jaxis.which,