Added support for press/release hardware keyboard events in iOS 13.4

src/events/SDL_events.c

@@ -35,9 +35,9 @@
 
 #undef SDL_PRIs64
 #ifdef __WIN32__
-#define SDL_PRIs64	"I64d"
+#define SDL_PRIs64  "I64d"
 #else
-#define SDL_PRIs64	"lld"
+#define SDL_PRIs64  "lld"
 #endif
 
 /* An arbitrary limit so we don't have unbounded growth */
@@ -678,10 +678,14 @@ SDL_PumpEvents(void)
 {
     SDL_VideoDevice *_this = SDL_GetVideoDevice();
 
+    /* Release any keys held down from last frame */
+    SDL_ReleaseAutoReleaseKeys();
+
     /* Get events from the video subsystem */
     if (_this) {
         _this->PumpEvents(_this);
     }
+
 #if !SDL_JOYSTICK_DISABLED
     /* Check for joystick state change */
     if ((!SDL_disabled_events[SDL_JOYAXISMOTION >> 8] || SDL_JoystickEventState(SDL_QUERY))) {

src/events/SDL_keyboard.c

@@ -33,6 +33,9 @@
 
 /* Global keyboard information */
 
+#define KEYBOARD_HARDWARE       0x01
+#define KEYBOARD_AUTORELEASE    0x02
+
 typedef struct SDL_Keyboard SDL_Keyboard;
 
 struct SDL_Keyboard
@@ -40,8 +43,10 @@ struct SDL_Keyboard
     /* Data common to all keyboards */
     SDL_Window *focus;
     Uint16 modstate;
+    Uint8 keysource[SDL_NUM_SCANCODES];
     Uint8 keystate[SDL_NUM_SCANCODES];
     SDL_Keycode keymap[SDL_NUM_SCANCODES];
+    SDL_bool autorelease_pending;
 };
 
 static SDL_Keyboard SDL_keyboard;
@@ -675,19 +680,20 @@ SDL_SetKeyboardFocus(SDL_Window * window)
     }
 }
 
-int
-SDL_SendKeyboardKey(Uint8 state, SDL_Scancode scancode)
+static int
+SDL_SendKeyboardKeyInternal(Uint8 source, Uint8 state, SDL_Scancode scancode)
 {
     SDL_Keyboard *keyboard = &SDL_keyboard;
     int posted;
     SDL_Keymod modifier;
     SDL_Keycode keycode;
     Uint32 type;
-    Uint8 repeat;
+    Uint8 repeat = SDL_FALSE;
 
-    if (!scancode) {
+    if (scancode == SDL_SCANCODE_UNKNOWN) {
         return 0;
     }
+
 #ifdef DEBUG_KEYBOARD
     printf("The '%s' key has been %s\n", SDL_GetScancodeName(scancode),
            state == SDL_PRESSED ? "pressed" : "released");
@@ -707,12 +713,20 @@ SDL_SendKeyboardKey(Uint8 state, SDL_Scancode scancode)
     }
 
     /* Drop events that don't change state */
-    repeat = (state && keyboard->keystate[scancode]);
-    if (keyboard->keystate[scancode] == state && !repeat) {
-#if 0
-        printf("Keyboard event didn't change state - dropped!\n");
-#endif
-        return 0;
+    if (state) {
+        if (keyboard->keystate[scancode]) {
+            if (!(keyboard->keysource[scancode] & source)) {
+                keyboard->keysource[scancode] |= source;
+                return 0;
+            }
+            repeat = SDL_TRUE;
+        }
+        keyboard->keysource[scancode] |= source;
+    } else {
+        if (!keyboard->keystate[scancode]) {
+            return 0;
+        }
+        keyboard->keysource[scancode] = 0;
     }
 
     /* Update internal keyboard state */
@@ -720,6 +734,10 @@ SDL_SendKeyboardKey(Uint8 state, SDL_Scancode scancode)
 
     keycode = keyboard->keymap[scancode];
 
+    if (source == KEYBOARD_AUTORELEASE) {
+        keyboard->autorelease_pending = SDL_TRUE;
+    }
+
     /* Update modifiers state if applicable */
     switch (keycode) {
     case SDLK_LCTRL:
@@ -785,6 +803,48 @@ SDL_SendKeyboardKey(Uint8 state, SDL_Scancode scancode)
     return (posted);
 }
 
+int
+SDL_SendKeyboardKey(Uint8 state, SDL_Scancode scancode)
+{
+    return SDL_SendKeyboardKeyInternal(KEYBOARD_HARDWARE, state, scancode);
+}
+
+int
+SDL_SendKeyboardKeyAutoRelease(SDL_Scancode scancode)
+{
+    return SDL_SendKeyboardKeyInternal(KEYBOARD_AUTORELEASE, SDL_PRESSED, scancode);
+}
+
+void
+SDL_ReleaseAutoReleaseKeys(void)
+{
+    SDL_Keyboard *keyboard = &SDL_keyboard;
+    SDL_Scancode scancode;
+
+    if (keyboard->autorelease_pending) {
+        for (scancode = SDL_SCANCODE_UNKNOWN; scancode < SDL_NUM_SCANCODES; ++scancode) {
+            if (keyboard->keysource[scancode] == KEYBOARD_AUTORELEASE) {
+                SDL_SendKeyboardKeyInternal(KEYBOARD_AUTORELEASE, SDL_RELEASED, scancode);
+            }
+        }
+        keyboard->autorelease_pending = SDL_FALSE;
+    }
+}
+
+SDL_bool
+SDL_HardwareKeyboardKeyPressed(void)
+{
+    SDL_Keyboard *keyboard = &SDL_keyboard;
+    SDL_Scancode scancode;
+
+    for (scancode = SDL_SCANCODE_UNKNOWN; scancode < SDL_NUM_SCANCODES; ++scancode) {
+        if ((keyboard->keysource[scancode] & KEYBOARD_HARDWARE) != 0) {
+            return SDL_TRUE;
+        }
+    }
+    return SDL_FALSE;
+}
+
 int
 SDL_SendKeyboardText(const char *text)
 {

src/events/SDL_keyboard_c.h

@@ -49,6 +49,13 @@ extern void SDL_SetKeyboardFocus(SDL_Window * window);
 
 /* Send a keyboard key event */
 extern int SDL_SendKeyboardKey(Uint8 state, SDL_Scancode scancode);
+extern int SDL_SendKeyboardKeyAutoRelease(SDL_Scancode scancode);
+
+/* Release all the autorelease keys */
+extern void SDL_ReleaseAutoReleaseKeys(void);
+
+/* Return true if any hardware key is pressed */
+extern SDL_bool SDL_HardwareKeyboardKeyPressed(void);
 
 /* Send keyboard text input */
 extern int SDL_SendKeyboardText(const char *text);