1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
|
# `const-cstr` [](https://crates.io/crates/const-cstr)
Create static C-compatible strings from Rust string literals.
Usage
------
Cargo.toml:
```toml
[dependencies]
const-cstr = "0.1"
```
Crate root:
```rust
#[macro_use] extern crate const_cstr;
```
Example
-------
```rust
#[macro_use] extern crate const_cstr;
use std::os::raw::c_char;
use std::ffi::CStr;
const_cstr! {
HELLO_CSTR = "Hello, world!";
// Multiple declarations can be made with one invocation.
// GOODNIGHT_CSTR = "Goodnight, sun!";
// But only with the same visibility:
// pub GOODNIGHT_CSTR = "Goodnight, sun!";
// ^~~ Error: expected identifier, found `pub`
}
// Imagine this is an `extern "C"` function linked from some other lib.
unsafe fn print_c_string(cstr: *const c_char) {
println!("{}", CStr::from_ptr(cstr).to_str().unwrap());
}
fn main() {
// When just passed a literal, returns an rvalue instead.
let goodnight_cstr = const_cstr!("Goodnight, sun!");
unsafe {
print_c_string(HELLO_CSTR.as_ptr());
print_c_string(goodnight_cstr.as_ptr());
}
}
```
Prints:
```notest
Hello, world!
Goodnight, sun!
```
## License
Licensed under either of
* Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
at your option.
### Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you shall be dual licensed as above, without any
additional terms or conditions.
|
