linux-stable/rust/macros/helpers.rs
Gary Guo b13c9880f9 rust: macros: take string literals in module!
Instead of taking binary string literals, take string ones instead,
making it easier for users to define a module, i.e. instead of
calling `module!` like:

    module! {
        ...
        name: b"rust_minimal",
        ...
    }

now it is called as:

    module! {
        ...
        name: "rust_minimal",
        ...
    }

Module names, aliases and license strings are restricted to
ASCII only. However, the author and the description allows UTF-8.

For simplicity (avoid parsing), escape sequences and raw string
literals are not yet handled.

Link: https://github.com/Rust-for-Linux/linux/issues/252
Link: https://lore.kernel.org/lkml/YukvvPOOu8uZl7+n@yadro.com/
Signed-off-by: Gary Guo <gary@garyguo.net>
[Reworded, adapted for upstream and applied latest changes]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2022-12-04 01:59:15 +01:00

63 lines
1.8 KiB
Rust

// SPDX-License-Identifier: GPL-2.0
use proc_macro::{token_stream, TokenTree};
pub(crate) fn try_ident(it: &mut token_stream::IntoIter) -> Option<String> {
if let Some(TokenTree::Ident(ident)) = it.next() {
Some(ident.to_string())
} else {
None
}
}
pub(crate) fn try_literal(it: &mut token_stream::IntoIter) -> Option<String> {
if let Some(TokenTree::Literal(literal)) = it.next() {
Some(literal.to_string())
} else {
None
}
}
pub(crate) fn try_string(it: &mut token_stream::IntoIter) -> Option<String> {
try_literal(it).and_then(|string| {
if string.starts_with('\"') && string.ends_with('\"') {
let content = &string[1..string.len() - 1];
if content.contains('\\') {
panic!("Escape sequences in string literals not yet handled");
}
Some(content.to_string())
} else if string.starts_with("r\"") {
panic!("Raw string literals are not yet handled");
} else {
None
}
})
}
pub(crate) fn expect_ident(it: &mut token_stream::IntoIter) -> String {
try_ident(it).expect("Expected Ident")
}
pub(crate) fn expect_punct(it: &mut token_stream::IntoIter) -> char {
if let TokenTree::Punct(punct) = it.next().expect("Reached end of token stream for Punct") {
punct.as_char()
} else {
panic!("Expected Punct");
}
}
pub(crate) fn expect_string(it: &mut token_stream::IntoIter) -> String {
try_string(it).expect("Expected string")
}
pub(crate) fn expect_string_ascii(it: &mut token_stream::IntoIter) -> String {
let string = try_string(it).expect("Expected string");
assert!(string.is_ascii(), "Expected ASCII string");
string
}
pub(crate) fn expect_end(it: &mut token_stream::IntoIter) {
if it.next().is_some() {
panic!("Expected end");
}
}