1 files changed, 27 insertions, 0 deletions
diff --git a/src/rust/tor_util/ffi.rs b/src/rust/tor_util/ffi.rs
new file mode 100644
index 0000000000..32779ed476
--- /dev/null
+++ b/src/rust/tor_util/ffi.rs
@@ -0,0 +1,27 @@
+// Copyright (c) 2016-2017, The Tor Project, Inc. */
+// See LICENSE for licensing information */
+
+//! FFI functions to announce Rust support during tor startup, only to be
+//! called from C.
+//!
+
+use tor_log::{LogSeverity, LogDomain};
+
+/// Returns a short string to announce Rust support during startup.
+///
+/// # Examples
+/// ```c
+/// char *rust_str = rust_welcome_string();
+/// printf("%s", rust_str);
+/// tor_free(rust_str);
+/// ```
+#[no_mangle]
+pub extern "C" fn rust_log_welcome_string() {
+    tor_log_msg!(
+        LogSeverity::Notice,
+        LogDomain::General,
+        "rust_log_welcome_string",
+        "Tor is running with Rust integration. Please report \
+        any bugs you encounter."
+    );
+}