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-rw-r--r--rust/macros/lib.rs117
-rw-r--r--rust/macros/module.rs2
-rw-r--r--rust/macros/paste.rs96
-rw-r--r--rust/macros/quote.rs12
-rw-r--r--rust/macros/zeroable.rs72
5 files changed, 298 insertions, 1 deletions
diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
index 3fc74cb4ea19..c42105c2ff96 100644
--- a/rust/macros/lib.rs
+++ b/rust/macros/lib.rs
@@ -7,9 +7,11 @@ mod quote;
mod concat_idents;
mod helpers;
mod module;
+mod paste;
mod pin_data;
mod pinned_drop;
mod vtable;
+mod zeroable;
use proc_macro::TokenStream;
@@ -246,3 +248,118 @@ pub fn pin_data(inner: TokenStream, item: TokenStream) -> TokenStream {
pub fn pinned_drop(args: TokenStream, input: TokenStream) -> TokenStream {
pinned_drop::pinned_drop(args, input)
}
+
+/// Paste identifiers together.
+///
+/// Within the `paste!` macro, identifiers inside `[<` and `>]` are concatenated together to form a
+/// single identifier.
+///
+/// This is similar to the [`paste`] crate, but with pasting feature limited to identifiers
+/// (literals, lifetimes and documentation strings are not supported). There is a difference in
+/// supported modifiers as well.
+///
+/// # Example
+///
+/// ```ignore
+/// use kernel::macro::paste;
+///
+/// macro_rules! pub_no_prefix {
+/// ($prefix:ident, $($newname:ident),+) => {
+/// paste! {
+/// $(pub(crate) const $newname: u32 = [<$prefix $newname>];)+
+/// }
+/// };
+/// }
+///
+/// pub_no_prefix!(
+/// binder_driver_return_protocol_,
+/// BR_OK,
+/// BR_ERROR,
+/// BR_TRANSACTION,
+/// BR_REPLY,
+/// BR_DEAD_REPLY,
+/// BR_TRANSACTION_COMPLETE,
+/// BR_INCREFS,
+/// BR_ACQUIRE,
+/// BR_RELEASE,
+/// BR_DECREFS,
+/// BR_NOOP,
+/// BR_SPAWN_LOOPER,
+/// BR_DEAD_BINDER,
+/// BR_CLEAR_DEATH_NOTIFICATION_DONE,
+/// BR_FAILED_REPLY
+/// );
+///
+/// assert_eq!(BR_OK, binder_driver_return_protocol_BR_OK);
+/// ```
+///
+/// # Modifiers
+///
+/// For each identifier, it is possible to attach one or multiple modifiers to
+/// it.
+///
+/// Currently supported modifiers are:
+/// * `span`: change the span of concatenated identifier to the span of the specified token. By
+/// default the span of the `[< >]` group is used.
+/// * `lower`: change the identifier to lower case.
+/// * `upper`: change the identifier to upper case.
+///
+/// ```ignore
+/// use kernel::macro::paste;
+///
+/// macro_rules! pub_no_prefix {
+/// ($prefix:ident, $($newname:ident),+) => {
+/// kernel::macros::paste! {
+/// $(pub(crate) const fn [<$newname:lower:span>]: u32 = [<$prefix $newname:span>];)+
+/// }
+/// };
+/// }
+///
+/// pub_no_prefix!(
+/// binder_driver_return_protocol_,
+/// BR_OK,
+/// BR_ERROR,
+/// BR_TRANSACTION,
+/// BR_REPLY,
+/// BR_DEAD_REPLY,
+/// BR_TRANSACTION_COMPLETE,
+/// BR_INCREFS,
+/// BR_ACQUIRE,
+/// BR_RELEASE,
+/// BR_DECREFS,
+/// BR_NOOP,
+/// BR_SPAWN_LOOPER,
+/// BR_DEAD_BINDER,
+/// BR_CLEAR_DEATH_NOTIFICATION_DONE,
+/// BR_FAILED_REPLY
+/// );
+///
+/// assert_eq!(br_ok(), binder_driver_return_protocol_BR_OK);
+/// ```
+///
+/// [`paste`]: https://docs.rs/paste/
+#[proc_macro]
+pub fn paste(input: TokenStream) -> TokenStream {
+ let mut tokens = input.into_iter().collect();
+ paste::expand(&mut tokens);
+ tokens.into_iter().collect()
+}
+
+/// Derives the [`Zeroable`] trait for the given struct.
+///
+/// This can only be used for structs where every field implements the [`Zeroable`] trait.
+///
+/// # Examples
+///
+/// ```rust,ignore
+/// #[derive(Zeroable)]
+/// pub struct DriverData {
+/// id: i64,
+/// buf_ptr: *mut u8,
+/// len: usize,
+/// }
+/// ```
+#[proc_macro_derive(Zeroable)]
+pub fn derive_zeroable(input: TokenStream) -> TokenStream {
+ zeroable::derive(input)
+}
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index fb1244f8c2e6..d62d8710d77a 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -199,7 +199,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
/// Used by the printing macros, e.g. [`info!`].
const __LOG_PREFIX: &[u8] = b\"{name}\\0\";
- /// The \"Rust loadable module\" mark, for `scripts/is_rust_module.sh`.
+ /// The \"Rust loadable module\" mark.
//
// This may be best done another way later on, e.g. as a new modinfo
// key or a new section. For the moment, keep it simple.
diff --git a/rust/macros/paste.rs b/rust/macros/paste.rs
new file mode 100644
index 000000000000..385a78434224
--- /dev/null
+++ b/rust/macros/paste.rs
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use proc_macro::{Delimiter, Group, Ident, Spacing, Span, TokenTree};
+
+fn concat(tokens: &[TokenTree], group_span: Span) -> TokenTree {
+ let mut tokens = tokens.iter();
+ let mut segments = Vec::new();
+ let mut span = None;
+ loop {
+ match tokens.next() {
+ None => break,
+ Some(TokenTree::Literal(lit)) => segments.push((lit.to_string(), lit.span())),
+ Some(TokenTree::Ident(ident)) => {
+ let mut value = ident.to_string();
+ if value.starts_with("r#") {
+ value.replace_range(0..2, "");
+ }
+ segments.push((value, ident.span()));
+ }
+ Some(TokenTree::Punct(p)) if p.as_char() == ':' => {
+ let Some(TokenTree::Ident(ident)) = tokens.next() else {
+ panic!("expected identifier as modifier");
+ };
+
+ let (mut value, sp) = segments.pop().expect("expected identifier before modifier");
+ match ident.to_string().as_str() {
+ // Set the overall span of concatenated token as current span
+ "span" => {
+ assert!(
+ span.is_none(),
+ "span modifier should only appear at most once"
+ );
+ span = Some(sp);
+ }
+ "lower" => value = value.to_lowercase(),
+ "upper" => value = value.to_uppercase(),
+ v => panic!("unknown modifier `{v}`"),
+ };
+ segments.push((value, sp));
+ }
+ _ => panic!("unexpected token in paste segments"),
+ };
+ }
+
+ let pasted: String = segments.into_iter().map(|x| x.0).collect();
+ TokenTree::Ident(Ident::new(&pasted, span.unwrap_or(group_span)))
+}
+
+pub(crate) fn expand(tokens: &mut Vec<TokenTree>) {
+ for token in tokens.iter_mut() {
+ if let TokenTree::Group(group) = token {
+ let delimiter = group.delimiter();
+ let span = group.span();
+ let mut stream: Vec<_> = group.stream().into_iter().collect();
+ // Find groups that looks like `[< A B C D >]`
+ if delimiter == Delimiter::Bracket
+ && stream.len() >= 3
+ && matches!(&stream[0], TokenTree::Punct(p) if p.as_char() == '<')
+ && matches!(&stream[stream.len() - 1], TokenTree::Punct(p) if p.as_char() == '>')
+ {
+ // Replace the group with concatenated token
+ *token = concat(&stream[1..stream.len() - 1], span);
+ } else {
+ // Recursively expand tokens inside the group
+ expand(&mut stream);
+ let mut group = Group::new(delimiter, stream.into_iter().collect());
+ group.set_span(span);
+ *token = TokenTree::Group(group);
+ }
+ }
+ }
+
+ // Path segments cannot contain invisible delimiter group, so remove them if any.
+ for i in (0..tokens.len().saturating_sub(3)).rev() {
+ // Looking for a double colon
+ if matches!(
+ (&tokens[i + 1], &tokens[i + 2]),
+ (TokenTree::Punct(a), TokenTree::Punct(b))
+ if a.as_char() == ':' && a.spacing() == Spacing::Joint && b.as_char() == ':'
+ ) {
+ match &tokens[i + 3] {
+ TokenTree::Group(group) if group.delimiter() == Delimiter::None => {
+ tokens.splice(i + 3..i + 4, group.stream());
+ }
+ _ => (),
+ }
+
+ match &tokens[i] {
+ TokenTree::Group(group) if group.delimiter() == Delimiter::None => {
+ tokens.splice(i..i + 1, group.stream());
+ }
+ _ => (),
+ }
+ }
+ }
+}
diff --git a/rust/macros/quote.rs b/rust/macros/quote.rs
index dddbb4e6f4cb..33a199e4f176 100644
--- a/rust/macros/quote.rs
+++ b/rust/macros/quote.rs
@@ -124,6 +124,18 @@ macro_rules! quote_spanned {
));
quote_spanned!(@proc $v $span $($tt)*);
};
+ (@proc $v:ident $span:ident ; $($tt:tt)*) => {
+ $v.push(::proc_macro::TokenTree::Punct(
+ ::proc_macro::Punct::new(';', ::proc_macro::Spacing::Alone)
+ ));
+ quote_spanned!(@proc $v $span $($tt)*);
+ };
+ (@proc $v:ident $span:ident + $($tt:tt)*) => {
+ $v.push(::proc_macro::TokenTree::Punct(
+ ::proc_macro::Punct::new('+', ::proc_macro::Spacing::Alone)
+ ));
+ quote_spanned!(@proc $v $span $($tt)*);
+ };
(@proc $v:ident $span:ident $id:ident $($tt:tt)*) => {
$v.push(::proc_macro::TokenTree::Ident(::proc_macro::Ident::new(stringify!($id), $span)));
quote_spanned!(@proc $v $span $($tt)*);
diff --git a/rust/macros/zeroable.rs b/rust/macros/zeroable.rs
new file mode 100644
index 000000000000..0d605c46ab3b
--- /dev/null
+++ b/rust/macros/zeroable.rs
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use crate::helpers::{parse_generics, Generics};
+use proc_macro::{TokenStream, TokenTree};
+
+pub(crate) fn derive(input: TokenStream) -> TokenStream {
+ let (
+ Generics {
+ impl_generics,
+ ty_generics,
+ },
+ mut rest,
+ ) = parse_generics(input);
+ // This should be the body of the struct `{...}`.
+ let last = rest.pop();
+ // Now we insert `Zeroable` as a bound for every generic parameter in `impl_generics`.
+ let mut new_impl_generics = Vec::with_capacity(impl_generics.len());
+ // Are we inside of a generic where we want to add `Zeroable`?
+ let mut in_generic = !impl_generics.is_empty();
+ // Have we already inserted `Zeroable`?
+ let mut inserted = false;
+ // Level of `<>` nestings.
+ let mut nested = 0;
+ for tt in impl_generics {
+ match &tt {
+ // If we find a `,`, then we have finished a generic/constant/lifetime parameter.
+ TokenTree::Punct(p) if nested == 0 && p.as_char() == ',' => {
+ if in_generic && !inserted {
+ new_impl_generics.extend(quote! { : ::kernel::init::Zeroable });
+ }
+ in_generic = true;
+ inserted = false;
+ new_impl_generics.push(tt);
+ }
+ // If we find `'`, then we are entering a lifetime.
+ TokenTree::Punct(p) if nested == 0 && p.as_char() == '\'' => {
+ in_generic = false;
+ new_impl_generics.push(tt);
+ }
+ TokenTree::Punct(p) if nested == 0 && p.as_char() == ':' => {
+ new_impl_generics.push(tt);
+ if in_generic {
+ new_impl_generics.extend(quote! { ::kernel::init::Zeroable + });
+ inserted = true;
+ }
+ }
+ TokenTree::Punct(p) if p.as_char() == '<' => {
+ nested += 1;
+ new_impl_generics.push(tt);
+ }
+ TokenTree::Punct(p) if p.as_char() == '>' => {
+ assert!(nested > 0);
+ nested -= 1;
+ new_impl_generics.push(tt);
+ }
+ _ => new_impl_generics.push(tt),
+ }
+ }
+ assert_eq!(nested, 0);
+ if in_generic && !inserted {
+ new_impl_generics.extend(quote! { : ::kernel::init::Zeroable });
+ }
+ quote! {
+ ::kernel::__derive_zeroable!(
+ parse_input:
+ @sig(#(#rest)*),
+ @impl_generics(#(#new_impl_generics)*),
+ @ty_generics(#(#ty_generics)*),
+ @body(#last),
+ );
+ }
+}
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