Convert extern fn to libdl call procedural macro.
use lazylink::lazylink;
/// comment!
#[lazylink]
#[link(name = "z")]
extern "C" {
/// zlib version
#[link_name = "zlibVersion"]
fn zlib_version() -> *const std::os::raw::c_char;
}
#[lazylink(fullname = "libc.so.6")]
mod libc {
/// comment!
extern "C" {
pub(crate) fn puts(v: *const std::os::raw::c_char);
}
}
fn main() {
let ver = unsafe {
zlib_version()
};
unsafe {
libc::puts(ver);
}
}
into
#![feature(prelude_import)]
#[prelude_import]
use std::prelude::v1::*;
#[macro_use]
extern crate std;
use lazylink::lazylink;
struct __LazyLinkbfde0578a8e5d844<'a> {
/// comment!
/// zlib version
zlib_version:
lazylink::libloading::Symbol<'a, unsafe extern "C" fn() -> *const std::os::raw::c_char>,
_phantom: std::marker::PhantomData<fn() -> &'a ()>,
}
impl<'a> __LazyLinkbfde0578a8e5d844<'a> {
unsafe fn new(
lib: &'a lazylink::libloading::Library,
) -> Result<Self, lazylink::libloading::Error> {
Ok(
Self { # [doc = " comment!"] # [doc = " zlib version"] zlib_version : lib . get (b"zlibVersion\x00") ? , _pha
ntom : std :: marker :: PhantomData , },
)
}
fn get() -> &'static __LazyLinkbfde0578a8e5d844<'static> {
static mut LIB: Option<lazylink::libloading::Library> = None;
static mut FNS: Option<__LazyLinkbfde0578a8e5d844<'static>> = None;
static ONCE: std::sync::Once = std::sync::Once::new();
ONCE.call_once(|| unsafe {
LIB = Some(
lazylink::libloading::Library::new(lazylink::libloading::library_filename("z"))
.unwrap(),
);
FNS = Some(__LazyLinkbfde0578a8e5d844::new(LIB.as_ref().unwrap()).unwrap());
});
unsafe { FNS.as_ref().unwrap() }
}
}
/// comment!
/// zlib version
unsafe fn zlib_version() -> *const std::os::raw::c_char {
(__LazyLinkbfde0578a8e5d844::get().zlib_version)()
}
mod libc {
struct __LazyLink79e825dc6d38824d<'a> {
/// comment!
puts: lazylink::libloading::Symbol<'a, unsafe extern "C" fn(*const std::os::raw::c_char)>,
_phantom: std::marker::PhantomData<fn() -> &'a ()>,
}
impl<'a> __LazyLink79e825dc6d38824d<'a> {
unsafe fn new(
lib: &'a lazylink::libloading::Library,
) -> Result<Self, lazylink::libloading::Error> {
Ok(
Self { # [doc = " comment!"] puts : lib . get (b"puts\x00") ? , _phantom : std :: marker :: PhantomData ,
},
)
}
fn get() -> &'static __LazyLink79e825dc6d38824d<'static> {
static mut LIB: Option<lazylink::libloading::Library> = None;
static mut FNS: Option<__LazyLink79e825dc6d38824d<'static>> = None;
const ONCE: std::sync::Once = std::sync::Once::new();
ONCE.call_once(|| unsafe {
LIB = Some(lazylink::libloading::Library::new("libc.so.6").unwrap());
FNS = Some(__LazyLink79e825dc6d38824d::new(LIB.as_ref().unwrap()).unwrap());
});
unsafe { FNS.as_ref().unwrap() }
}
}
/// comment!
pub(crate) unsafe fn puts(v: *const std::os::raw::c_char) {
(__LazyLink79e825dc6d38824d::get().puts)(v)
}
}
fn main() {
let ver = unsafe { zlib_version() };
unsafe {
libc::puts(ver);
}
}
Licensed under either of
- Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.