Commit eb6f92cd authored Oct 04, 2024 by Danilo Krummrich Committed by Miguel Ojeda Oct 15, 2024

rust: str: test: replace `alloc::format`



The current implementation of tests in str.rs use `format!` to format
strings for comparison, which, internally, creates a new `String`.

In order to prepare for getting rid of Rust's alloc crate, we have to
cut this dependency. Instead, implement `format!` for `CString`.

Note that for userspace tests, `Kmalloc`, which is backing `CString`'s
memory, is just a type alias to `Cmalloc`.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-27-dakr@kernel.org


Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

parent dd09538f

rust/kernel/str.rs

+22 −1

Original line number	Diff line number	Diff line
		@@ -524,7 +524,28 @@ macro_rules! c_str {
		#[cfg(test)]
		mod tests {
		use super::*;
		use alloc::format;

		struct String(CString);

		impl String {
		fn from_fmt(args: fmt::Arguments<'_>) -> Self {
		String(CString::try_from_fmt(args).unwrap())
		}
		}

		impl Deref for String {
		type Target = str;

		fn deref(&self) -> &str {
		self.0.to_str().unwrap()
		}
		}

		macro_rules! format {
		($($f:tt)*) => ({
		&String::from_fmt(kernel::fmt!($($f)))
		})
		}

		const ALL_ASCII_CHARS: &'static str =
		"\\x01\\x02\\x03\\x04\\x05\\x06\\x07\\x08\\x09\\x0a\\x0b\\x0c\\x0d\\x0e\\x0f\