bit_arithmetic.rs

    pub fn inode_get_project(inode: u64) -> u16 {
        (inode >> 48) as u16
    }

    pub fn inode_get_category(inode: u64) -> u8 {
        ((inode >> 40) & 0xff) as u8
    }

    pub fn inode_get_item(inode: u64) -> u32 {
        ((inode >> 8) & 0xffffffff) as u32
    }

    pub fn inode_get_reserved(inode: u64) -> u8 {
        (inode & 0xff) as u8
    }
    
    pub fn inode_create(project: u16, category: u8, item: u32, reserved: u8) -> u64 {
        let inode: u64 = ((project as u64) << 48) | ((category as u64) << 40) | ((item as u64) << 8) | (reserved as u64);
        return inode;
    }
    
fn main() {
    // let inode = inode_create(1, 2, 3, 4);
    // println!("{}, {}", inode_get_project(inode), inode_get_category(inode));
    
    // let inode: u64 = (65535 << 48) + (255 << 40) + (0xffffffff << 8) + 255;
    let inode = inode_create(65535, 255, 0xffffffff, 255);
    
    println!("project - {}", inode_get_project(inode));
    println!("category - {}", inode_get_category(inode));
    println!("item - {}", inode_get_item(inode));
    println!("reserved - {}", inode_get_reserved(inode));
    
    // println!("Hello, world!");
}