diff options
Diffstat (limited to 'rust/qemu-api-macros/src')
| -rw-r--r-- | rust/qemu-api-macros/src/bits.rs | 213 | ||||
| -rw-r--r-- | rust/qemu-api-macros/src/lib.rs | 271 | ||||
| -rw-r--r-- | rust/qemu-api-macros/src/tests.rs | 137 |
3 files changed, 0 insertions, 621 deletions
diff --git a/rust/qemu-api-macros/src/bits.rs b/rust/qemu-api-macros/src/bits.rs deleted file mode 100644 index a80a3b9fee..0000000000 --- a/rust/qemu-api-macros/src/bits.rs +++ /dev/null @@ -1,213 +0,0 @@ -// SPDX-License-Identifier: MIT or Apache-2.0 or GPL-2.0-or-later - -// shadowing is useful together with "if let" -#![allow(clippy::shadow_unrelated)] - -use proc_macro2::{ - Delimiter, Group, Ident, Punct, Spacing, Span, TokenStream, TokenTree, TokenTree as TT, -}; -use syn::Error; - -pub struct BitsConstInternal { - typ: TokenTree, -} - -fn paren(ts: TokenStream) -> TokenTree { - TT::Group(Group::new(Delimiter::Parenthesis, ts)) -} - -fn ident(s: &'static str) -> TokenTree { - TT::Ident(Ident::new(s, Span::call_site())) -} - -fn punct(ch: char) -> TokenTree { - TT::Punct(Punct::new(ch, Spacing::Alone)) -} - -/// Implements a recursive-descent parser that translates Boolean expressions on -/// bitmasks to invocations of `const` functions defined by the `bits!` macro. -impl BitsConstInternal { - // primary ::= '(' or ')' - // | ident - // | '!' ident - fn parse_primary( - &self, - tok: TokenTree, - it: &mut dyn Iterator<Item = TokenTree>, - out: &mut TokenStream, - ) -> Result<Option<TokenTree>, Error> { - let next = match tok { - TT::Group(ref g) => { - if g.delimiter() != Delimiter::Parenthesis && g.delimiter() != Delimiter::None { - return Err(Error::new(g.span(), "expected parenthesis")); - } - let mut stream = g.stream().into_iter(); - let Some(first_tok) = stream.next() else { - return Err(Error::new(g.span(), "expected operand, found ')'")); - }; - let mut output = TokenStream::new(); - // start from the lowest precedence - let next = self.parse_or(first_tok, &mut stream, &mut output)?; - if let Some(tok) = next { - return Err(Error::new(tok.span(), format!("unexpected token {tok}"))); - } - out.extend(Some(paren(output))); - it.next() - } - TT::Ident(_) => { - let mut output = TokenStream::new(); - output.extend([ - self.typ.clone(), - TT::Punct(Punct::new(':', Spacing::Joint)), - TT::Punct(Punct::new(':', Spacing::Joint)), - tok, - ]); - out.extend(Some(paren(output))); - it.next() - } - TT::Punct(ref p) => { - if p.as_char() != '!' { - return Err(Error::new(p.span(), "expected operand")); - } - let Some(rhs_tok) = it.next() else { - return Err(Error::new(p.span(), "expected operand at end of input")); - }; - let next = self.parse_primary(rhs_tok, it, out)?; - out.extend([punct('.'), ident("invert"), paren(TokenStream::new())]); - next - } - _ => { - return Err(Error::new(tok.span(), "unexpected literal")); - } - }; - Ok(next) - } - - fn parse_binop< - F: Fn( - &Self, - TokenTree, - &mut dyn Iterator<Item = TokenTree>, - &mut TokenStream, - ) -> Result<Option<TokenTree>, Error>, - >( - &self, - tok: TokenTree, - it: &mut dyn Iterator<Item = TokenTree>, - out: &mut TokenStream, - ch: char, - f: F, - method: &'static str, - ) -> Result<Option<TokenTree>, Error> { - let mut next = f(self, tok, it, out)?; - while next.is_some() { - let op = next.as_ref().unwrap(); - let TT::Punct(ref p) = op else { break }; - if p.as_char() != ch { - break; - } - - let Some(rhs_tok) = it.next() else { - return Err(Error::new(p.span(), "expected operand at end of input")); - }; - let mut rhs = TokenStream::new(); - next = f(self, rhs_tok, it, &mut rhs)?; - out.extend([punct('.'), ident(method), paren(rhs)]); - } - Ok(next) - } - - // sub ::= primary ('-' primary)* - pub fn parse_sub( - &self, - tok: TokenTree, - it: &mut dyn Iterator<Item = TokenTree>, - out: &mut TokenStream, - ) -> Result<Option<TokenTree>, Error> { - self.parse_binop(tok, it, out, '-', Self::parse_primary, "difference") - } - - // and ::= sub ('&' sub)* - fn parse_and( - &self, - tok: TokenTree, - it: &mut dyn Iterator<Item = TokenTree>, - out: &mut TokenStream, - ) -> Result<Option<TokenTree>, Error> { - self.parse_binop(tok, it, out, '&', Self::parse_sub, "intersection") - } - - // xor ::= and ('&' and)* - fn parse_xor( - &self, - tok: TokenTree, - it: &mut dyn Iterator<Item = TokenTree>, - out: &mut TokenStream, - ) -> Result<Option<TokenTree>, Error> { - self.parse_binop(tok, it, out, '^', Self::parse_and, "symmetric_difference") - } - - // or ::= xor ('|' xor)* - pub fn parse_or( - &self, - tok: TokenTree, - it: &mut dyn Iterator<Item = TokenTree>, - out: &mut TokenStream, - ) -> Result<Option<TokenTree>, Error> { - self.parse_binop(tok, it, out, '|', Self::parse_xor, "union") - } - - pub fn parse( - it: &mut dyn Iterator<Item = TokenTree>, - ) -> Result<proc_macro2::TokenStream, Error> { - let mut pos = Span::call_site(); - let mut typ = proc_macro2::TokenStream::new(); - - // Gobble everything up to an `@` sign, which is followed by a - // parenthesized expression; that is, all token trees except the - // last two form the type. - let next = loop { - let tok = it.next(); - if let Some(ref t) = tok { - pos = t.span(); - } - match tok { - None => break None, - Some(TT::Punct(ref p)) if p.as_char() == '@' => { - let tok = it.next(); - if let Some(ref t) = tok { - pos = t.span(); - } - break tok; - } - Some(x) => typ.extend(Some(x)), - } - }; - - let Some(tok) = next else { - return Err(Error::new( - pos, - "expected expression, do not call this macro directly", - )); - }; - let TT::Group(ref _group) = tok else { - return Err(Error::new( - tok.span(), - "expected parenthesis, do not call this macro directly", - )); - }; - let mut out = TokenStream::new(); - let state = Self { - typ: TT::Group(Group::new(Delimiter::None, typ)), - }; - - let next = state.parse_primary(tok, it, &mut out)?; - - // A parenthesized expression is a single production of the grammar, - // so the input must have reached the last token. - if let Some(tok) = next { - return Err(Error::new(tok.span(), format!("unexpected token {tok}"))); - } - Ok(out) - } -} diff --git a/rust/qemu-api-macros/src/lib.rs b/rust/qemu-api-macros/src/lib.rs deleted file mode 100644 index 959726efe6..0000000000 --- a/rust/qemu-api-macros/src/lib.rs +++ /dev/null @@ -1,271 +0,0 @@ -// Copyright 2024, Linaro Limited -// Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org> -// SPDX-License-Identifier: GPL-2.0-or-later - -use proc_macro::TokenStream; -use quote::quote; -use syn::{ - parse_macro_input, parse_quote, punctuated::Punctuated, spanned::Spanned, token::Comma, Data, - DeriveInput, Error, Field, Fields, FieldsUnnamed, Ident, Meta, Path, Token, Variant, -}; -mod bits; -use bits::BitsConstInternal; - -#[cfg(test)] -mod tests; - -fn get_fields<'a>( - input: &'a DeriveInput, - msg: &str, -) -> Result<&'a Punctuated<Field, Comma>, Error> { - let Data::Struct(ref s) = &input.data else { - return Err(Error::new( - input.ident.span(), - format!("Struct required for {msg}"), - )); - }; - let Fields::Named(ref fs) = &s.fields else { - return Err(Error::new( - input.ident.span(), - format!("Named fields required for {msg}"), - )); - }; - Ok(&fs.named) -} - -fn get_unnamed_field<'a>(input: &'a DeriveInput, msg: &str) -> Result<&'a Field, Error> { - let Data::Struct(ref s) = &input.data else { - return Err(Error::new( - input.ident.span(), - format!("Struct required for {msg}"), - )); - }; - let Fields::Unnamed(FieldsUnnamed { ref unnamed, .. }) = &s.fields else { - return Err(Error::new( - s.fields.span(), - format!("Tuple struct required for {msg}"), - )); - }; - if unnamed.len() != 1 { - return Err(Error::new( - s.fields.span(), - format!("A single field is required for {msg}"), - )); - } - Ok(&unnamed[0]) -} - -fn is_c_repr(input: &DeriveInput, msg: &str) -> Result<(), Error> { - let expected = parse_quote! { #[repr(C)] }; - - if input.attrs.iter().any(|attr| attr == &expected) { - Ok(()) - } else { - Err(Error::new( - input.ident.span(), - format!("#[repr(C)] required for {msg}"), - )) - } -} - -fn is_transparent_repr(input: &DeriveInput, msg: &str) -> Result<(), Error> { - let expected = parse_quote! { #[repr(transparent)] }; - - if input.attrs.iter().any(|attr| attr == &expected) { - Ok(()) - } else { - Err(Error::new( - input.ident.span(), - format!("#[repr(transparent)] required for {msg}"), - )) - } -} - -fn derive_object_or_error(input: DeriveInput) -> Result<proc_macro2::TokenStream, Error> { - is_c_repr(&input, "#[derive(Object)]")?; - - let name = &input.ident; - let parent = &get_fields(&input, "#[derive(Object)]")? - .get(0) - .ok_or_else(|| { - Error::new( - input.ident.span(), - "#[derive(Object)] requires a parent field", - ) - })? - .ident; - - Ok(quote! { - ::qemu_api::assert_field_type!(#name, #parent, - ::qemu_api::qom::ParentField<<#name as ::qemu_api::qom::ObjectImpl>::ParentType>); - - ::qemu_api::module_init! { - MODULE_INIT_QOM => unsafe { - ::qemu_api::bindings::type_register_static(&<#name as ::qemu_api::qom::ObjectImpl>::TYPE_INFO); - } - } - }) -} - -#[proc_macro_derive(Object)] -pub fn derive_object(input: TokenStream) -> TokenStream { - let input = parse_macro_input!(input as DeriveInput); - - derive_object_or_error(input) - .unwrap_or_else(syn::Error::into_compile_error) - .into() -} - -fn derive_opaque_or_error(input: DeriveInput) -> Result<proc_macro2::TokenStream, Error> { - is_transparent_repr(&input, "#[derive(Wrapper)]")?; - - let name = &input.ident; - let field = &get_unnamed_field(&input, "#[derive(Wrapper)]")?; - let typ = &field.ty; - - Ok(quote! { - unsafe impl ::qemu_api::cell::Wrapper for #name { - type Wrapped = <#typ as ::qemu_api::cell::Wrapper>::Wrapped; - } - impl #name { - pub unsafe fn from_raw<'a>(ptr: *mut <Self as ::qemu_api::cell::Wrapper>::Wrapped) -> &'a Self { - let ptr = ::std::ptr::NonNull::new(ptr).unwrap().cast::<Self>(); - unsafe { ptr.as_ref() } - } - - pub const fn as_mut_ptr(&self) -> *mut <Self as ::qemu_api::cell::Wrapper>::Wrapped { - self.0.as_mut_ptr() - } - - pub const fn as_ptr(&self) -> *const <Self as ::qemu_api::cell::Wrapper>::Wrapped { - self.0.as_ptr() - } - - pub const fn as_void_ptr(&self) -> *mut ::core::ffi::c_void { - self.0.as_void_ptr() - } - - pub const fn raw_get(slot: *mut Self) -> *mut <Self as ::qemu_api::cell::Wrapper>::Wrapped { - slot.cast() - } - } - }) -} - -#[proc_macro_derive(Wrapper)] -pub fn derive_opaque(input: TokenStream) -> TokenStream { - let input = parse_macro_input!(input as DeriveInput); - - derive_opaque_or_error(input) - .unwrap_or_else(syn::Error::into_compile_error) - .into() -} - -#[allow(non_snake_case)] -fn get_repr_uN(input: &DeriveInput, msg: &str) -> Result<Path, Error> { - let repr = input.attrs.iter().find(|attr| attr.path().is_ident("repr")); - if let Some(repr) = repr { - let nested = repr.parse_args_with(Punctuated::<Meta, Token![,]>::parse_terminated)?; - for meta in nested { - match meta { - Meta::Path(path) if path.is_ident("u8") => return Ok(path), - Meta::Path(path) if path.is_ident("u16") => return Ok(path), - Meta::Path(path) if path.is_ident("u32") => return Ok(path), - Meta::Path(path) if path.is_ident("u64") => return Ok(path), - _ => {} - } - } - } - - Err(Error::new( - input.ident.span(), - format!("#[repr(u8/u16/u32/u64) required for {msg}"), - )) -} - -fn get_variants(input: &DeriveInput) -> Result<&Punctuated<Variant, Comma>, Error> { - let Data::Enum(ref e) = &input.data else { - return Err(Error::new( - input.ident.span(), - "Cannot derive TryInto for union or struct.", - )); - }; - if let Some(v) = e.variants.iter().find(|v| v.fields != Fields::Unit) { - return Err(Error::new( - v.fields.span(), - "Cannot derive TryInto for enum with non-unit variants.", - )); - } - Ok(&e.variants) -} - -#[rustfmt::skip::macros(quote)] -fn derive_tryinto_body( - name: &Ident, - variants: &Punctuated<Variant, Comma>, - repr: &Path, -) -> Result<proc_macro2::TokenStream, Error> { - let discriminants: Vec<&Ident> = variants.iter().map(|f| &f.ident).collect(); - - Ok(quote! { - #(const #discriminants: #repr = #name::#discriminants as #repr;)* - match value { - #(#discriminants => core::result::Result::Ok(#name::#discriminants),)* - _ => core::result::Result::Err(value), - } - }) -} - -#[rustfmt::skip::macros(quote)] -fn derive_tryinto_or_error(input: DeriveInput) -> Result<proc_macro2::TokenStream, Error> { - let repr = get_repr_uN(&input, "#[derive(TryInto)]")?; - let name = &input.ident; - let body = derive_tryinto_body(name, get_variants(&input)?, &repr)?; - let errmsg = format!("invalid value for {name}"); - - Ok(quote! { - impl #name { - #[allow(dead_code)] - pub const fn into_bits(self) -> #repr { - self as #repr - } - - #[allow(dead_code)] - pub const fn from_bits(value: #repr) -> Self { - match ({ - #body - }) { - Ok(x) => x, - Err(_) => panic!(#errmsg), - } - } - } - impl core::convert::TryFrom<#repr> for #name { - type Error = #repr; - - #[allow(ambiguous_associated_items)] - fn try_from(value: #repr) -> Result<Self, #repr> { - #body - } - } - }) -} - -#[proc_macro_derive(TryInto)] -pub fn derive_tryinto(input: TokenStream) -> TokenStream { - let input = parse_macro_input!(input as DeriveInput); - - derive_tryinto_or_error(input) - .unwrap_or_else(syn::Error::into_compile_error) - .into() -} - -#[proc_macro] -pub fn bits_const_internal(ts: TokenStream) -> TokenStream { - let ts = proc_macro2::TokenStream::from(ts); - let mut it = ts.into_iter(); - - BitsConstInternal::parse(&mut it) - .unwrap_or_else(syn::Error::into_compile_error) - .into() -} diff --git a/rust/qemu-api-macros/src/tests.rs b/rust/qemu-api-macros/src/tests.rs deleted file mode 100644 index 6028cdbc4c..0000000000 --- a/rust/qemu-api-macros/src/tests.rs +++ /dev/null @@ -1,137 +0,0 @@ -// Copyright 2025, Linaro Limited -// Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org> -// SPDX-License-Identifier: GPL-2.0-or-later - -use quote::quote; - -use super::*; - -macro_rules! derive_compile_fail { - ($derive_fn:ident, $input:expr, $($error_msg:expr),+ $(,)?) => {{ - let input: proc_macro2::TokenStream = $input; - let error_msg = &[$( quote! { ::core::compile_error! { $error_msg } } ),*]; - let derive_fn: fn(input: syn::DeriveInput) -> Result<proc_macro2::TokenStream, syn::Error> = - $derive_fn; - - let input: syn::DeriveInput = syn::parse2(input).unwrap(); - let result = derive_fn(input); - let err = result.unwrap_err().into_compile_error(); - assert_eq!( - err.to_string(), - quote! { #(#error_msg)* }.to_string() - ); - }}; -} - -macro_rules! derive_compile { - ($derive_fn:ident, $input:expr, $($expected:tt)*) => {{ - let input: proc_macro2::TokenStream = $input; - let expected: proc_macro2::TokenStream = $($expected)*; - let derive_fn: fn(input: syn::DeriveInput) -> Result<proc_macro2::TokenStream, syn::Error> = - $derive_fn; - - let input: syn::DeriveInput = syn::parse2(input).unwrap(); - let result = derive_fn(input).unwrap(); - assert_eq!(result.to_string(), expected.to_string()); - }}; -} - -#[test] -fn test_derive_object() { - derive_compile_fail!( - derive_object_or_error, - quote! { - #[derive(Object)] - struct Foo { - _unused: [u8; 0], - } - }, - "#[repr(C)] required for #[derive(Object)]" - ); - derive_compile!( - derive_object_or_error, - quote! { - #[derive(Object)] - #[repr(C)] - struct Foo { - _unused: [u8; 0], - } - }, - quote! { - ::qemu_api::assert_field_type!( - Foo, - _unused, - ::qemu_api::qom::ParentField<<Foo as ::qemu_api::qom::ObjectImpl>::ParentType> - ); - ::qemu_api::module_init! { - MODULE_INIT_QOM => unsafe { - ::qemu_api::bindings::type_register_static(&<Foo as ::qemu_api::qom::ObjectImpl>::TYPE_INFO); - } - } - } - ); -} - -#[test] -fn test_derive_tryinto() { - derive_compile_fail!( - derive_tryinto_or_error, - quote! { - #[derive(TryInto)] - struct Foo { - _unused: [u8; 0], - } - }, - "#[repr(u8/u16/u32/u64) required for #[derive(TryInto)]" - ); - derive_compile!( - derive_tryinto_or_error, - quote! { - #[derive(TryInto)] - #[repr(u8)] - enum Foo { - First = 0, - Second, - } - }, - quote! { - impl Foo { - #[allow(dead_code)] - pub const fn into_bits(self) -> u8 { - self as u8 - } - - #[allow(dead_code)] - pub const fn from_bits(value: u8) -> Self { - match ({ - const First: u8 = Foo::First as u8; - const Second: u8 = Foo::Second as u8; - match value { - First => core::result::Result::Ok(Foo::First), - Second => core::result::Result::Ok(Foo::Second), - _ => core::result::Result::Err(value), - } - }) { - Ok(x) => x, - Err(_) => panic!("invalid value for Foo"), - } - } - } - - impl core::convert::TryFrom<u8> for Foo { - type Error = u8; - - #[allow(ambiguous_associated_items)] - fn try_from(value: u8) -> Result<Self, u8> { - const First: u8 = Foo::First as u8; - const Second: u8 = Foo::Second as u8; - match value { - First => core::result::Result::Ok(Foo::First), - Second => core::result::Result::Ok(Foo::Second), - _ => core::result::Result::Err(value), - } - } - } - } - ); -} |