1#![allow(non_upper_case_globals)]
 2#![allow(non_camel_case_types)]
 3#![allow(non_snake_case)]
 4
 5use crate::PlatformDispatcher;
 6use async_task::Runnable;
 7use objc::{
 8    class, msg_send,
 9    runtime::{BOOL, YES},
10    sel, sel_impl,
11};
12use std::ffi::c_void;
13
14include!(concat!(env!("OUT_DIR"), "/dispatch_sys.rs"));
15
16pub fn dispatch_get_main_queue() -> dispatch_queue_t {
17    unsafe { &_dispatch_main_q as *const _ as dispatch_queue_t }
18}
19
20pub struct MacDispatcher;
21
22impl PlatformDispatcher for MacDispatcher {
23    fn is_main_thread(&self) -> bool {
24        let is_main_thread: BOOL = unsafe { msg_send![class!(NSThread), isMainThread] };
25        is_main_thread == YES
26    }
27
28    fn dispatch(&self, runnable: Runnable) {
29        unsafe {
30            dispatch_async_f(
31                dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT.try_into().unwrap(), 0),
32                runnable.into_raw() as *mut c_void,
33                Some(trampoline),
34            );
35        }
36    }
37
38    fn dispatch_on_main_thread(&self, runnable: Runnable) {
39        unsafe {
40            dispatch_async_f(
41                dispatch_get_main_queue(),
42                runnable.into_raw() as *mut c_void,
43                Some(trampoline),
44            );
45        }
46    }
47}
48
49extern "C" fn trampoline(runnable: *mut c_void) {
50    let task = unsafe { Runnable::from_raw(runnable as *mut ()) };
51    task.run();
52}
53
54// #include <dispatch/dispatch.h>
55
56// int main(void) {
57
58//     dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
59//         // Do some lengthy background work here...
60//         printf("Background Work\n");
61
62//         dispatch_async(dispatch_get_main_queue(), ^{
63//             // Once done, update your UI on the main queue here.
64//             printf("UI Updated\n");
65
66//         });
67//     });
68
69//     sleep(3);  // prevent the program from terminating immediately
70
71//     return 0;
72// }
73// ```