x11_dl/
internal.rs

1// x11-rs: Rust bindings for X11 libraries
2// The X11 libraries are available under the MIT license.
3// These bindings are public domain.
4
5use std::cmp::min;
6use std::mem::{size_of, zeroed};
7
8//
9// public functions
10//
11
12pub unsafe fn mem_eq<T: Sized>(a: &T, b: &T) -> bool {
13    let a_addr = a as *const T as usize;
14    let b_addr = b as *const T as usize;
15
16    for i in 0..size_of::<T>() {
17        if *((a_addr + i) as *const u8) != *((b_addr + i) as *const u8) {
18            return false;
19        }
20    }
21
22    true
23}
24
25pub unsafe fn transmute_union<I, O>(input: &I) -> O
26where
27    I: Sized,
28    O: Sized,
29{
30    let mut output: O = zeroed();
31    let copy_len = min(size_of::<I>(), size_of::<O>());
32
33    for i in 0..copy_len {
34        *((&mut output as *mut O as usize + i) as *mut u8) =
35            *((input as *const I as usize + i) as *const u8);
36    }
37
38    output
39}