| use std::ffi::{CStr, CString}; |
| use std::borrow::Cow; |
| use std::os::raw; |
| |
| use crate::Error; |
| |
| /// Checks for last byte and avoids allocating if it is zero. |
| /// |
| /// Non-last null bytes still result in an error. |
| pub(crate) fn cstr_cow_from_bytes<'a>(slice: &'a [u8]) -> Result<Cow<'a, CStr>, Error> { |
| static ZERO: raw::c_char = 0; |
| Ok(match slice.last() { |
| // Slice out of 0 elements |
| None => unsafe { Cow::Borrowed(CStr::from_ptr(&ZERO)) }, |
| // Slice with trailing 0 |
| Some(&0) => Cow::Borrowed(CStr::from_bytes_with_nul(slice) |
| .map_err(|source| Error::CreateCStringWithTrailing { source })?), |
| // Slice with no trailing 0 |
| Some(_) => Cow::Owned(CString::new(slice) |
| .map_err(|source| Error::CreateCString { source })?), |
| }) |
| } |
| |
| #[inline] |
| pub(crate) fn ensure_compatible_types<T, E>() -> Result<(), Error> { |
| if ::std::mem::size_of::<T>() != ::std::mem::size_of::<E>() { |
| Err(Error::IncompatibleSize) |
| } else { |
| Ok(()) |
| } |
| } |