First commit

src/lib.rs

@@ -0,0 +1,47 @@
+use ::safer_ffi::prelude::*;
+
+/// A `struct` usable from both Rust and C
+#[derive_ReprC]
+#[repr(C)]
+#[derive(Debug, Clone, Copy)]
+pub struct Point {
+    x: f64,
+    y: f64,
+}
+
+/* Export a Rust function to the C world. */
+/// Returns the middle point of `[a, b]`.
+#[ffi_export]
+fn mid_point(a: Option<repr_c::Box<Point>>, b: Option<repr_c::Box<Point>>) -> repr_c::Box<Point> {
+    let a = a.unwrap();
+    let b = b.unwrap();
+    repr_c::Box::new(Point {
+        x: (a.x + b.x) / 2.,
+        y: (a.y + b.y) / 2.,
+    })
+}
+
+/// Pretty-prints a point using Rust's formatting logic.
+#[ffi_export]
+fn print_point(point: Option<repr_c::Box<Point>>) {
+    println!("{:?}", point);
+}
+
+#[ffi_export]
+fn new_point(x: f64, y: f64) -> repr_c::Box<Point> {
+    repr_c::Box::new(Point { x, y })
+}
+
+#[ffi_export]
+fn free_point(point: Option<repr_c::Box<Point>>) {
+    drop(point)
+}
+
+/// The following test function is necessary for the header generation.
+#[::safer_ffi::cfg_headers]
+#[test]
+fn generate_headers() -> ::std::io::Result<()> {
+    ::safer_ffi::headers::builder()
+        .to_file("bdk_ffi.h")?
+        .generate()
+}