feat: Add event filters (#5)

src/func_constants.inc

@@ -12,6 +12,7 @@ SF_REDRAW               = 12
 SF_GET_BUTTON           = 17
 SF_SYSTEM_GET           = 26
     SSF_SYS_LANG    = 5
+SF_SET_EVENTS_MASK      = 40
 SF_BOARD                = 63
     SSF_DEBUG_WRITE = 1
 SF_SYS_MISC             = 68

src/modules/threads.rs

@@ -1,4 +1,4 @@
-use crate::sys;
+use crate::sys::{self, set_event_mask};
 
 pub fn exit() -> ! {
     unsafe { sys::exit() }
@@ -6,18 +6,19 @@ pub fn exit() -> ! {
 
 #[non_exhaustive]
 pub enum Event {
-    Redraw,
-    KeyPress,
-    BtnPress,
-    BgRedraw,
-    Mouse,
-    IPC,
-    Network,
-    Debug,
+    Redraw = 1 << 0,
+    KeyPress = 1 << 1,
+    BtnPress = 1 << 2,
+    BgRedraw = 1 << 4,
+    Mouse = 1 << 5,
+    IPC = 1 << 6,
+    Network = 1 << 7,
+    Debug = 1 << 8,
 }
 
-pub fn fetch_event() -> Option<Event> {
-    match unsafe { sys::wait_event() } {
+pub fn fetch_event(flags: u32) -> Option<Event> {
+    let old_mask = unsafe { sys::set_event_mask(flags as u32) };
+    let e = match unsafe { sys::wait_event() } {
         1 => Some(Event::Redraw),
         2 => Some(Event::KeyPress),
         3 => Some(Event::BtnPress),
@@ -27,5 +28,7 @@ pub fn fetch_event() -> Option<Event> {
         8 => Some(Event::Network),
         9 => Some(Event::Debug),
         _ => None,
-    }
+    };
+    unsafe { set_event_mask(old_mask) };
+    e
 }

src/sys.rs

@@ -40,6 +40,10 @@ extern "C" {
     #[link_name = "_get_lang"]
     pub fn get_lang() -> u32;
 
+    // 40
+    #[link_name = "_set_event_mask"]
+    pub fn set_event_mask(mask: u32) -> u32;
+
     // 63.1
     #[link_name = "_debug_write"]
     pub fn _debug_write(cl: u8);

src/syscalls.S

@@ -18,6 +18,7 @@ section '.text'
     public _free
     public _get_lang
     public _load_dll
+    public _set_event_mask
 
 _exit:
     mov eax, SF_TERMINATE_PROCESS
@@ -126,3 +127,10 @@ _load_dll:
     mov ecx, [esp + 4 * 1]
     int 0x40
     ret
+
+_set_event_mask:
+    mov eax, SF_SET_EVENTS_MASK
+    mov ebx, [esp + 4 * 1]
+    int 0x40
+    ret
+