Rust: start writing binding

pkgs/rust/Cargo.toml

@@ -13,3 +13,4 @@ categories = ["api-bindings", "embedded", "external-ffi-bindings", "no-std", "pa
 publish = true
 
 [dependencies]
+libc = "0.2.113"

pkgs/rust/rustfmt.toml

@@ -0,0 +1 @@
+max_width = 80

pkgs/rust/src/lib.rs

@@ -1,8 +1,24 @@
+#[cfg(test)]
+use libc::c_char;
+
+#[link(name = "kernaux")]
+extern "C" {
+    #[cfg(test)]
+    fn kernaux_utoa10(value: u64, buffer: *mut c_char);
+}
+
 #[cfg(test)]
 mod tests {
+    use super::*;
+
+    use std::ffi::CStr;
+
     #[test]
-    fn it_works() {
-        let result = 2 + 2;
-        assert_eq!(result, 4);
+    fn utoa10() {
+        let mut buffer: [i8; 1000] = [0; 1000];
+        unsafe { kernaux_utoa10(123, buffer.as_mut_ptr()) };
+        let result =
+            unsafe { CStr::from_ptr(buffer.as_ptr()) }.to_str().unwrap();
+        assert_eq!(result, "123");
     }
 }