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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
commit | 43a97878ce14b72f0981164f87f2e35e14151312 (patch) | |
tree | 620249daf56c0258faa40cbdcf9cfba06de2a846 /servo/components/to_shmem_derive | |
parent | Initial commit. (diff) | |
download | firefox-43a97878ce14b72f0981164f87f2e35e14151312.tar.xz firefox-43a97878ce14b72f0981164f87f2e35e14151312.zip |
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | servo/components/to_shmem_derive/Cargo.toml | 18 | ||||
-rw-r--r-- | servo/components/to_shmem_derive/lib.rs | 26 | ||||
-rw-r--r-- | servo/components/to_shmem_derive/to_shmem.rs | 78 |
3 files changed, 122 insertions, 0 deletions
diff --git a/servo/components/to_shmem_derive/Cargo.toml b/servo/components/to_shmem_derive/Cargo.toml new file mode 100644 index 0000000000..7029ca355a --- /dev/null +++ b/servo/components/to_shmem_derive/Cargo.toml @@ -0,0 +1,18 @@ +[package] +name = "to_shmem_derive" +version = "0.0.1" +authors = ["The Servo Project Developers"] +license = "MPL-2.0" +publish = false + +[lib] +path = "lib.rs" +proc-macro = true + +[dependencies] +darling = { version = "0.14", default-features = false } +derive_common = { path = "../derive_common" } +proc-macro2 = "1" +quote = "1" +syn = { version = "1", default-features = false, features = ["derive", "parsing"] } +synstructure = "0.12" diff --git a/servo/components/to_shmem_derive/lib.rs b/servo/components/to_shmem_derive/lib.rs new file mode 100644 index 0000000000..b820e7f85d --- /dev/null +++ b/servo/components/to_shmem_derive/lib.rs @@ -0,0 +1,26 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at https://mozilla.org/MPL/2.0/. */ + +#![recursion_limit = "128"] + +#[macro_use] +extern crate darling; +extern crate derive_common; +extern crate proc_macro; +extern crate proc_macro2; +#[macro_use] +extern crate quote; +#[macro_use] +extern crate syn; +extern crate synstructure; + +use proc_macro::TokenStream; + +mod to_shmem; + +#[proc_macro_derive(ToShmem, attributes(shmem))] +pub fn derive_to_shmem(stream: TokenStream) -> TokenStream { + let input = syn::parse(stream).unwrap(); + to_shmem::derive(input).into() +} diff --git a/servo/components/to_shmem_derive/to_shmem.rs b/servo/components/to_shmem_derive/to_shmem.rs new file mode 100644 index 0000000000..157730c5a5 --- /dev/null +++ b/servo/components/to_shmem_derive/to_shmem.rs @@ -0,0 +1,78 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at https://mozilla.org/MPL/2.0/. */ + +use derive_common::cg; +use proc_macro2::TokenStream; +use syn; +use synstructure::{BindStyle, Structure}; + +pub fn derive(mut input: syn::DeriveInput) -> TokenStream { + let mut where_clause = input.generics.where_clause.take(); + let attrs = cg::parse_input_attrs::<ShmemInputAttrs>(&input); + if !attrs.no_bounds { + for param in input.generics.type_params() { + cg::add_predicate(&mut where_clause, parse_quote!(#param: ::to_shmem::ToShmem)); + } + } + for variant in Structure::new(&input).variants() { + for binding in variant.bindings() { + let attrs = cg::parse_field_attrs::<ShmemFieldAttrs>(&binding.ast()); + if attrs.field_bound { + let ty = &binding.ast().ty; + cg::add_predicate(&mut where_clause, parse_quote!(#ty: ::to_shmem::ToShmem)) + } + } + } + + input.generics.where_clause = where_clause; + + // Do all of the `to_shmem()?` calls before the `ManuallyDrop::into_inner()` + // calls, so that we don't drop a value in the shared memory buffer if one + // of the `to_shmem`s fails. + let match_body = cg::fmap2_match( + &input, + BindStyle::Ref, + |binding| { + quote! { + ::to_shmem::ToShmem::to_shmem(#binding, builder)? + } + }, + |binding| { + Some(quote! { + ::std::mem::ManuallyDrop::into_inner(#binding) + }) + }, + ); + + let name = &input.ident; + let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl(); + + quote! { + impl #impl_generics ::to_shmem::ToShmem for #name #ty_generics #where_clause { + #[allow(unused_variables, unreachable_code)] + fn to_shmem( + &self, + builder: &mut ::to_shmem::SharedMemoryBuilder, + ) -> ::to_shmem::Result<Self> { + Ok(::std::mem::ManuallyDrop::new( + match *self { + #match_body + } + )) + } + } + } +} + +#[derive(Default, FromDeriveInput)] +#[darling(attributes(shmem), default)] +pub struct ShmemInputAttrs { + pub no_bounds: bool, +} + +#[derive(Default, FromField)] +#[darling(attributes(shmem), default)] +pub struct ShmemFieldAttrs { + pub field_bound: bool, +} |