/// This macro creates a zero-overhead &CStr by adding a NUL terminator to
/// the string literal passed into it at compile-time. Use it like:
///
/// ```
/// let some_const_cstr = const_cstr!("abc");
/// ```
///
/// The above is roughly equivalent to:
///
/// ```
/// let some_const_cstr = CStr::from_bytes_with_nul(b"abc\0").unwrap()
/// ```
///
/// Note that macro only checks the string literal for internal NULs if
/// debug-assertions are enabled in order to avoid runtime overhead in release
/// builds.
#[macro_export]
macro_rules! const_cstr {
($s:expr) => ({
use std::ffi::CStr;
let str_plus_nul = concat!($s, "\0");
if cfg!(debug_assertions) {
CStr::from_bytes_with_nul(str_plus_nul.as_bytes()).unwrap()
} else {
unsafe {
CStr::from_bytes_with_nul_unchecked(str_plus_nul.as_bytes())
}
}
})
}