Vendor things

third-party/vendor/x11-dl/src/internal.rs

@@ -0,0 +1,39 @@
+// x11-rs: Rust bindings for X11 libraries
+// The X11 libraries are available under the MIT license.
+// These bindings are public domain.
+
+use std::cmp::min;
+use std::mem::{size_of, zeroed};
+
+//
+// public functions
+//
+
+pub unsafe fn mem_eq<T: Sized>(a: &T, b: &T) -> bool {
+    let a_addr = a as *const T as usize;
+    let b_addr = b as *const T as usize;
+
+    for i in 0..size_of::<T>() {
+        if *((a_addr + i) as *const u8) != *((b_addr + i) as *const u8) {
+            return false;
+        }
+    }
+
+    true
+}
+
+pub unsafe fn transmute_union<I, O>(input: &I) -> O
+where
+    I: Sized,
+    O: Sized,
+{
+    let mut output: O = zeroed();
+    let copy_len = min(size_of::<I>(), size_of::<O>());
+
+    for i in 0..copy_len {
+        *((&mut output as *mut O as usize + i) as *mut u8) =
+            *((input as *const I as usize + i) as *const u8);
+    }
+
+    output
+}