From fbf8fb328d1bfe3bd17d5c5626cb485a1ca1a50d Mon Sep 17 00:00:00 2001 From: Benno Lossin Date: Sat, 8 Mar 2025 11:04:00 +0000 Subject: rust: move pin-init API into its own directory In preparation of splitting off the pin-init crate from the kernel crate, move all pin-init API code (including proc-macros) into `rust/pin-init`. Moved modules have their import path adjusted via the `#[path = "..."]` attribute. This allows the files to still be imported in the kernel crate even though the files are in different directories. Code that is moved out of files (but the file itself stays where it is) is imported via the `include!` macro. This also allows the code to be moved while still being part of the kernel crate. Note that this commit moves the generics parsing code out of the GPL-2.0 file `rust/macros/helpers.rs` into the Apache-2.0 OR MIT file `rust/pin_init/internal/src/helpers.rs`. I am the sole author of that code and it already is available with that license at [1]. The same is true for the entry-points of the proc-macros `pin_data`, `pinned_drop` and `derive_zeroable` in `rust/macros/lib.rs` that are moved to `rust/pin_data/internal/src/lib.rs`. Although there are some smaller patches that fix the doctests. Link: https://github.com/Rust-for-Linux/pinned-init [1] Signed-off-by: Benno Lossin Reviewed-by: Andreas Hindborg Reviewed-by: Fiona Behrens Tested-by: Andreas Hindborg Link: https://lore.kernel.org/r/20250308110339.2997091-3-benno.lossin@proton.me Signed-off-by: Miguel Ojeda --- rust/pin-init/internal/src/helpers.rs | 147 ++++++++++++++++++++++++++++++++++ 1 file changed, 147 insertions(+) create mode 100644 rust/pin-init/internal/src/helpers.rs (limited to 'rust/pin-init/internal/src/helpers.rs') diff --git a/rust/pin-init/internal/src/helpers.rs b/rust/pin-init/internal/src/helpers.rs new file mode 100644 index 000000000000..2f4fc75c014e --- /dev/null +++ b/rust/pin-init/internal/src/helpers.rs @@ -0,0 +1,147 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + +/// Parsed generics. +/// +/// See the field documentation for an explanation what each of the fields represents. +/// +/// # Examples +/// +/// ```rust,ignore +/// # let input = todo!(); +/// let (Generics { decl_generics, impl_generics, ty_generics }, rest) = parse_generics(input); +/// quote! { +/// struct Foo<$($decl_generics)*> { +/// // ... +/// } +/// +/// impl<$impl_generics> Foo<$ty_generics> { +/// fn foo() { +/// // ... +/// } +/// } +/// } +/// ``` +pub(crate) struct Generics { + /// The generics with bounds and default values (e.g. `T: Clone, const N: usize = 0`). + /// + /// Use this on type definitions e.g. `struct Foo<$decl_generics> ...` (or `union`/`enum`). + pub(crate) decl_generics: Vec, + /// The generics with bounds (e.g. `T: Clone, const N: usize`). + /// + /// Use this on `impl` blocks e.g. `impl<$impl_generics> Trait for ...`. + pub(crate) impl_generics: Vec, + /// The generics without bounds and without default values (e.g. `T, N`). + /// + /// Use this when you use the type that is declared with these generics e.g. + /// `Foo<$ty_generics>`. + pub(crate) ty_generics: Vec, +} + +/// Parses the given `TokenStream` into `Generics` and the rest. +/// +/// The generics are not present in the rest, but a where clause might remain. +pub(crate) fn parse_generics(input: TokenStream) -> (Generics, Vec) { + // The generics with bounds and default values. + let mut decl_generics = vec![]; + // `impl_generics`, the declared generics with their bounds. + let mut impl_generics = vec![]; + // Only the names of the generics, without any bounds. + let mut ty_generics = vec![]; + // Tokens not related to the generics e.g. the `where` token and definition. + let mut rest = vec![]; + // The current level of `<`. + let mut nesting = 0; + let mut toks = input.into_iter(); + // If we are at the beginning of a generic parameter. + let mut at_start = true; + let mut skip_until_comma = false; + while let Some(tt) = toks.next() { + if nesting == 1 && matches!(&tt, TokenTree::Punct(p) if p.as_char() == '>') { + // Found the end of the generics. + break; + } else if nesting >= 1 { + decl_generics.push(tt.clone()); + } + match tt.clone() { + TokenTree::Punct(p) if p.as_char() == '<' => { + if nesting >= 1 && !skip_until_comma { + // This is inside of the generics and part of some bound. + impl_generics.push(tt); + } + nesting += 1; + } + TokenTree::Punct(p) if p.as_char() == '>' => { + // This is a parsing error, so we just end it here. + if nesting == 0 { + break; + } else { + nesting -= 1; + if nesting >= 1 && !skip_until_comma { + // We are still inside of the generics and part of some bound. + impl_generics.push(tt); + } + } + } + TokenTree::Punct(p) if skip_until_comma && p.as_char() == ',' => { + if nesting == 1 { + impl_generics.push(tt.clone()); + impl_generics.push(tt); + skip_until_comma = false; + } + } + _ if !skip_until_comma => { + match nesting { + // If we haven't entered the generics yet, we still want to keep these tokens. + 0 => rest.push(tt), + 1 => { + // Here depending on the token, it might be a generic variable name. + match tt.clone() { + TokenTree::Ident(i) if at_start && i.to_string() == "const" => { + let Some(name) = toks.next() else { + // Parsing error. + break; + }; + impl_generics.push(tt); + impl_generics.push(name.clone()); + ty_generics.push(name.clone()); + decl_generics.push(name); + at_start = false; + } + TokenTree::Ident(_) if at_start => { + impl_generics.push(tt.clone()); + ty_generics.push(tt); + at_start = false; + } + TokenTree::Punct(p) if p.as_char() == ',' => { + impl_generics.push(tt.clone()); + ty_generics.push(tt); + at_start = true; + } + // Lifetimes begin with `'`. + TokenTree::Punct(p) if p.as_char() == '\'' && at_start => { + impl_generics.push(tt.clone()); + ty_generics.push(tt); + } + // Generics can have default values, we skip these. + TokenTree::Punct(p) if p.as_char() == '=' => { + skip_until_comma = true; + } + _ => impl_generics.push(tt), + } + } + _ => impl_generics.push(tt), + } + } + _ => {} + } + } + rest.extend(toks); + ( + Generics { + impl_generics, + decl_generics, + ty_generics, + }, + rest, + ) +} -- cgit From dbd5058ba60c3499b24a7133a4e2e24dba6ea77b Mon Sep 17 00:00:00 2001 From: Benno Lossin Date: Sat, 8 Mar 2025 11:05:09 +0000 Subject: rust: make pin-init its own crate Rename relative paths inside of the crate to still refer to the same items, also rename paths inside of the kernel crate and adjust the build system to build the crate. [ Remove the `expect` (and thus the `lint_reasons` feature) since the tree now uses `quote!` from `rust/macros/export.rs`. Remove the `TokenStream` import removal, since it is now used as well. In addition, temporarily (i.e. just for this commit) use an `--extern force:alloc` to prevent an unknown `new_uninit` error in the `rustdoc` target. For context, please see a similar case in: https://lore.kernel.org/lkml/20240422090644.525520-1-ojeda@kernel.org/ And adjusted the message above. - Miguel ] Signed-off-by: Benno Lossin Reviewed-by: Fiona Behrens Tested-by: Andreas Hindborg Link: https://lore.kernel.org/r/20250308110339.2997091-16-benno.lossin@proton.me Signed-off-by: Miguel Ojeda --- rust/pin-init/internal/src/helpers.rs | 2 ++ 1 file changed, 2 insertions(+) (limited to 'rust/pin-init/internal/src/helpers.rs') diff --git a/rust/pin-init/internal/src/helpers.rs b/rust/pin-init/internal/src/helpers.rs index 2f4fc75c014e..78521ba19d0b 100644 --- a/rust/pin-init/internal/src/helpers.rs +++ b/rust/pin-init/internal/src/helpers.rs @@ -1,5 +1,7 @@ // SPDX-License-Identifier: Apache-2.0 OR MIT +use proc_macro::{TokenStream, TokenTree}; + /// Parsed generics. /// /// See the field documentation for an explanation what each of the fields represents. -- cgit From 7cb5dee4c8349f8cc3e1ce529df4e18ebe3fed2e Mon Sep 17 00:00:00 2001 From: Benno Lossin Date: Sat, 8 Mar 2025 11:05:22 +0000 Subject: rust: pin-init: internal: synchronize with user-space version Synchronize the internal macros crate with the user-space version that uses the quote crate [1] instead of a custom `quote!` macro. The imports in the different version are achieved using `cfg` on the kernel config value. This cfg is always set in the kernel and never set in the user-space version. Since the quote crate requires the proc_macro2 crate, imports also need to be adjusted and `.into()` calls have to be inserted. Link: https://crates.io/crates/quote [1] Signed-off-by: Benno Lossin Reviewed-by: Andreas Hindborg Tested-by: Andreas Hindborg Reviewed-by: Fiona Behrens Link: https://lore.kernel.org/r/20250308110339.2997091-19-benno.lossin@proton.me Signed-off-by: Miguel Ojeda --- rust/pin-init/internal/src/helpers.rs | 3 +++ 1 file changed, 3 insertions(+) (limited to 'rust/pin-init/internal/src/helpers.rs') diff --git a/rust/pin-init/internal/src/helpers.rs b/rust/pin-init/internal/src/helpers.rs index 78521ba19d0b..236f989a50f2 100644 --- a/rust/pin-init/internal/src/helpers.rs +++ b/rust/pin-init/internal/src/helpers.rs @@ -1,5 +1,8 @@ // SPDX-License-Identifier: Apache-2.0 OR MIT +#[cfg(not(kernel))] +use proc_macro2 as proc_macro; + use proc_macro::{TokenStream, TokenTree}; /// Parsed generics. -- cgit