X-Git-Url: https://piware.de/gitweb/?p=learn-rust.git;a=blobdiff_plain;f=call-rust-from-c%2Fsrc%2Flib.rs;fp=call-rust-from-c%2Fsrc%2Flib.rs;h=f5e43842b908f49ffbbe5e3799f75156aa186521;hp=0000000000000000000000000000000000000000;hb=7ed2d982ac15df78e852fd5835d137881536a4ef;hpb=b74219aafd6977a99de7e52bc47f956b0b45cb01

diff --git a/call-rust-from-c/src/lib.rs b/call-rust-from-c/src/lib.rs
new file mode 100644
index 0000000..f5e4384
--- /dev/null
+++ b/call-rust-from-c/src/lib.rs
@@ -0,0 +1,26 @@
+use std::os::raw;
+
+/// Return The Answer.
+///
+/// # Example
+///
+/// ```
+/// let a = call_rust_from_c::answer();
+/// assert_eq!(a, 42);
+/// ```
+#[no_mangle]
+// C 'int'; it does not actually hurt to have more specific types such as int32_t, but it's good to know that plain ints work
+pub extern "C" fn answer() -> raw::c_int {
+    return 42;
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_answer() {
+        assert_eq!(answer(), 42);
+    }
+}