From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- rust/macros/pinned_drop.rs | 49 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 rust/macros/pinned_drop.rs (limited to 'rust/macros/pinned_drop.rs') diff --git a/rust/macros/pinned_drop.rs b/rust/macros/pinned_drop.rs new file mode 100644 index 0000000000..88fb72b206 --- /dev/null +++ b/rust/macros/pinned_drop.rs @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + +use proc_macro::{TokenStream, TokenTree}; + +pub(crate) fn pinned_drop(_args: TokenStream, input: TokenStream) -> TokenStream { + let mut toks = input.into_iter().collect::>(); + assert!(!toks.is_empty()); + // Ensure that we have an `impl` item. + assert!(matches!(&toks[0], TokenTree::Ident(i) if i.to_string() == "impl")); + // Ensure that we are implementing `PinnedDrop`. + let mut nesting: usize = 0; + let mut pinned_drop_idx = None; + for (i, tt) in toks.iter().enumerate() { + match tt { + TokenTree::Punct(p) if p.as_char() == '<' => { + nesting += 1; + } + TokenTree::Punct(p) if p.as_char() == '>' => { + nesting = nesting.checked_sub(1).unwrap(); + continue; + } + _ => {} + } + if i >= 1 && nesting == 0 { + // Found the end of the generics, this should be `PinnedDrop`. + assert!( + matches!(tt, TokenTree::Ident(i) if i.to_string() == "PinnedDrop"), + "expected 'PinnedDrop', found: '{:?}'", + tt + ); + pinned_drop_idx = Some(i); + break; + } + } + let idx = pinned_drop_idx + .unwrap_or_else(|| panic!("Expected an `impl` block implementing `PinnedDrop`.")); + // Fully qualify the `PinnedDrop`, as to avoid any tampering. + toks.splice(idx..idx, quote!(::kernel::init::)); + // Take the `{}` body and call the declarative macro. + if let Some(TokenTree::Group(last)) = toks.pop() { + let last = last.stream(); + quote!(::kernel::__pinned_drop! { + @impl_sig(#(#toks)*), + @impl_body(#last), + }) + } else { + TokenStream::from_iter(toks) + } +} -- cgit v1.2.3