sheaf: task dispatching made simple

     ⣀                    ⢀⡀  
    ⣰⣿⡆               ⣄ ⢀⣴⣿⡇  
 ⢠⣄ ⣿⣿⡿ ⢀⡀           ⣸⣿ ⢸⣿⡿   
 ⠈⣿⣆⠘⠟⢀⣼⣿⠁    ⢀    ⣠⡀⢹⣿⡇⠈⣁⣤⣶⠖ 
 ⣀⠙⢿⡆⢰⣿⡿⠃    ⣰⣿⡇   ⣿⣧⠈⠏⢠⣾⠿⠿⠋  
 ⢻⣷⡀⠁⠈⢁⣤⣶⠁⣴⡄⢸⣿⣿⡇   ⣿⣿⠂⣀⣠⣤⣤⡄
 ⠈⢿⣿ ⣴⣿⡿⠃ ⣿⣷ ⠟⢁⣠⣶⠇ ⠈⠁⢴⣿⡿⠟⠉  
   ⠙ ⠛⠋⠁ ⣦⠈⢿⠃⣰⣿⡿⠏  ⣾⠆    ⣴⣿ 
    ⣿    ⣿⣷⡀ ⠋⣁⣤⡤ ⢰⡏ ⢸⣆ ⣾⣿⡿   
    ⣿    ⢻⣿⠃⣰⣿⣿⠟ ⢀⡿  ⢿⣿⡄⠹⠛⢁⣤⡤  
    ⣿     ⠈⡀⠛⠋⠁  ⣼⡇⢰⣆⠈⢿⠇⢠⣾⣿⠟  
    ⣿     ⢸⠃    ⢀⣿ ⢸⣿⣆⠈ ⠋⣉⣠⡄ 
    ⣿     ⣿     ⢸⡇ ⠘⢿⡟⢀⣶⣿⡿⠋   
    ⢻⡆   ⢸⡏     ⣾⡇  ⢀⣀⠘⠛⠉     
    ⠘⠓   ⠘⠃     ⠛⠁  ⠘⠋        

# features

a minimal, zero-dependency, proof-of-concept library for task dispatching in c:

- pthreads for compute-heavy tasks, inspired by goroutines
- cooperative async for io-heavy tasks, inspired by the javascript event loop
- defer statement for simple RAII, leveraging gcc's cleanup attribute

# usage

```
$ tail -n +10 src/demo_go.c

    static void task(u32 id) {
        usleep((u32)((rand() % 1000) * 1000));
        printf("finished task %u\n", id);
    }

    i32 main(void) {
        u32 *results = malloc(4 * sizeof(u32));
        defer({ free(results); printf("cleaned up\n"); });

        go({ task(1); });
        go({ task(2); });
        go({ task(3); });

        wait();
        return EXIT_SUCCESS;
    }

$ make demo-go

    finished task 2
    finished task 1
    finished task 3
    cleaned up

$ tail -n +6 src/demo_async.c

    static void ping(void) {
        for (u8 i = 0; i < 2; i++) {
            printf("ping\n");
            async_yield();
        }
    }

    static void pong(void) {
        for (u8 i = 0; i < 2; i++) {
            printf("pong\n");
            async_yield();
        }
    }

    i32 main(void) {
        async_spawn(ping);
        async_spawn(pong);
        async_run_all();
        return EXIT_SUCCESS;
    }

$ make demo-async

    ping
    pong
    ping
    pong
```