| // Copyright 2013 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| // ignore-wasm32-bare no libc to test ffi with |
| |
| #[link(name = "rust_test_helpers", kind = "static")] |
| extern { |
| fn rust_interesting_average(_: u64, ...) -> f64; |
| } |
| |
| pub fn main() { |
| // Call without variadic arguments |
| unsafe { |
| assert!(rust_interesting_average(0).is_nan()); |
| } |
| |
| // Call with direct arguments |
| unsafe { |
| assert_eq!(rust_interesting_average(1, 10i64, 10.0f64) as i64, 20); |
| } |
| |
| // Call with named arguments, variable number of them |
| let (x1, x2, x3, x4) = (10i64, 10.0f64, 20i64, 20.0f64); |
| unsafe { |
| assert_eq!(rust_interesting_average(2, x1, x2, x3, x4) as i64, 30); |
| } |
| |
| // A function that takes a function pointer |
| unsafe fn call(fp: unsafe extern fn(u64, ...) -> f64) { |
| let (x1, x2, x3, x4) = (10i64, 10.0f64, 20i64, 20.0f64); |
| assert_eq!(fp(2, x1, x2, x3, x4) as i64, 30); |
| } |
| |
| unsafe { |
| call(rust_interesting_average); |
| |
| // Make a function pointer, pass indirectly |
| let x: unsafe extern fn(u64, ...) -> f64 = rust_interesting_average; |
| call(x); |
| } |
| } |