defs: allow NULL callbacks in gint_call()

include/gint/defs/call.h

@@ -153,7 +153,8 @@ static GINLINE int gint_call(gint_call_t cb)
 	int (*f)(int r4, int r5, int r6, int r7) = cb.function;
 #endif
 
-	return f(cb.args[0].i, cb.args[1].i, cb.args[2].i, cb.args[3].i);
+        gint_call_arg_t *args = cb.args;
+	return f ? f(args[0].i, args[1].i, args[2].i, args[3].i) : -1;
 }
 
 //---

src/dma/dma.c

@@ -160,11 +160,8 @@ static void dma_interrupt_transfer_ended(int channel)
 	if(dma_wait_ics[channel])
 		cpu_csleep_cancel(dma_wait_ics[channel]);
 
-	if(dma_callbacks[channel].function)
-	{
-		gint_call(dma_callbacks[channel]);
-		dma_callbacks[channel] = GINT_CALL_NULL;
-	}
+	gint_call(dma_callbacks[channel]);
+	dma_callbacks[channel] = GINT_CALL_NULL;
 }
 
 /* dma_channel_wait(): Wait for a particular channel's transfer to finish

src/kernel/world.c

@@ -149,7 +149,7 @@ int gint_world_switch(gint_call_t call)
 	if(canary)
 		*canary = 0xb7c0ffee;
 
-	int rc = call.function ? gint_call(call) : 0;
+	int rc = gint_call(call);
 
 	/* The canary check needs to occur before switching in the gint world;
 	   otherwise we just crash due to the overflow. gint_panic() isn't

src/render-cg/dupdate.c

@@ -12,8 +12,7 @@ void dupdate(void)
 
 	r61524_display(gint_vram, 0, 224, method);
 
-	gint_call_t hook = dupdate_get_hook();
-	if(hook.function) gint_call(hook);
+	gint_call(dupdate_get_hook());
 
 	/* Switch buffers if triple buffering is enabled */
 	dvram_switch();

src/render-fx/dupdate.c

@@ -28,8 +28,7 @@ void dupdate(void)
 		t6k11_display(gint_vram, 0, 64, 16);
 	}
 
-	gint_call_t hook = dupdate_get_hook();
-	if(hook.function) gint_call(hook);
+	gint_call(dupdate_get_hook());
 }
 __attribute__((alias("dupdate")))
 void _WEAK_dupdate(void);

src/usb/pipes.c

@@ -263,10 +263,10 @@ static void finish_transfer(struct transfer volatile *t, int pipe)
 	t->used = 0;
 
 	/* Disable the interrupt */
-	if(pipe) USB.BEMPENB &= ~(1 << pipe);
-
-	if(t->callback.function) gint_call(t->callback);
+	if(pipe != 0)
+		USB.BEMPENB &= ~(1 << pipe);
 
+	gint_call(t->callback);
 	USB_TRACE("finish_transfer()");
 }
 
@@ -287,14 +287,14 @@ static void finish_round(struct transfer volatile *t, int pipe)
 	t->flying = 0;
 
 	/* Account for auto-transfers */
-	if(t->used == pipe_bufsize(pipe)) t->used = 0;
+	if(t->used == pipe_bufsize(pipe))
+		t->used = 0;
 
 	/* At the end, free the FIFO and invoke the callback. Hold the
 	   controller until the pipe is committed */
-	if(t->size == 0)
-	{
+	if(t->size == 0) {
 		t->data = NULL;
-		if(t->callback.function) gint_call(t->callback);
+		gint_call(t->callback);
 	}
 
 	USB_TRACE("finish_round()");

src/usb/usb.c

@@ -266,13 +266,9 @@ static void usb_interrupt_handler(void)
 		if(USB.INTSTS0.DVSQ == 3)
 		{
 			usb_configure_clear_pipes();
-
 			usb_open_status = true;
-			if(usb_open_callback.function)
-			{
-				gint_call(usb_open_callback);
-				usb_open_callback = GINT_CALL_NULL;
-			}
+			gint_call(usb_open_callback);
+			usb_open_callback = GINT_CALL_NULL;
 		}
 	}
 	else if(USB.INTSTS0.BEMP)