我正在尝试在C语言中使用Rust代码。我将no mangle
用于Rust,将extern "C"
用于将在Rust中定义的C ++代码。但是,我不断收到未定义的引用,试图将Rust库链接到我的C ++代码中]
interface.rs
use std::os::raw::{c_int};
type OnDataCallback = unsafe extern "C" fn(data: *mut u8, len: usize) -> c_int;
static mut onDataCallback_: Option<OnDataCallback> = None;
#[no_mangle]
pub extern "C" fn registerOnDataCallback(cb: Option<OnDataCallback>) -> c_int
{
unsafe{onDataCallback_ = cb;}
return 0;
}
#[no_mangle]
pub extern "C" fn doSomething()
{
let mut s = String::from("hello world\0");
unsafe {
unsafe{onDataCallback_.unwrap()(s.as_mut_ptr() , 100)};
}
}
interface.cpp
#include <iostream>
typedef int (*onDataCallback_)(uint8_t *data, size_t len);
extern "C" int registerOnDataCallback(onDataCallback_ cb);
extern "C" void doSomething();
extern "C" int onDataCallback(uint8_t *data, size_t len) {
std::cout << "called onData with size " + len << std::endl;
}
int main() {
registerOnDataCallback(&onDataCallback);
doSomething();
getchar();
return 0;
}
我如何编译:
rustc --crate-type=staticlib interface.rs
g++ -o rust_c -L. -linterface interface.cpp
错误:
/tmp/ccgjsC7i.o: In function `main':
interface.cpp:(.text+0x51): undefined reference to `registerOnDataCallback'
interface.cpp:(.text+0x56): undefined reference to `doSomething'
collect2: error: ld returned 1 exit status
我关注了2个不同的教程。我也尝试过货运:
[package]
name = "smoltcp_c_interface"
version = "0.1.0"
[lib]
name = "smoltcp_c_interface"
path = "interface.rs"
crate-type = ["staticlib"]
[dependencies]
libc = "0.2.0"
然后做了cargo build
,并尝试以与上述相同的方式与g++
链接。相同的未定义引用。
链接器从左到右搜索符号。在需要符号的源文件后面指定带有符号的库。
g++ -o rust_c -L. interface.cpp -linterface
然后添加防锈依赖项--pthread
和dlsym -ldl
。