-
-
Notifications
You must be signed in to change notification settings - Fork 19
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Update repr parsing logic to handle multiple attrs
- Loading branch information
Showing
3 changed files
with
117 additions
and
162 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -1,176 +1,137 @@ | ||
| use proc_macro2::{Span, TokenStream}; | ||
| use quote::{quote, ToTokens, TokenStreamExt}; | ||
| use syn::{ | ||
| meta::ParseNestedMeta, parenthesized, spanned::Spanned, Error, LitInt, | ||
| }; | ||
| use quote::{quote, ToTokens}; | ||
| use syn::{parenthesized, token, Attribute, Error, Ident, LitInt}; | ||
|
|
||
| #[derive(Clone, Copy)] | ||
| pub enum IntRepr { | ||
| pub enum Primitive { | ||
| I8, | ||
| I16, | ||
| I32, | ||
| I64, | ||
| I128, | ||
| Isize, | ||
| U8, | ||
| U16, | ||
| U32, | ||
| U64, | ||
| U128, | ||
| Usize, | ||
| } | ||
|
|
||
| impl ToTokens for IntRepr { | ||
| fn to_tokens(&self, tokens: &mut TokenStream) { | ||
| impl Primitive { | ||
| const ALL: [Self; 10] = [ | ||
| Self::I8, | ||
| Self::I16, | ||
| Self::I32, | ||
| Self::I64, | ||
| Self::Isize, | ||
| Self::U8, | ||
| Self::U16, | ||
| Self::U32, | ||
| Self::U64, | ||
| Self::Usize, | ||
| ]; | ||
|
|
||
| pub const fn as_str(&self) -> &'static str { | ||
| match self { | ||
| Self::I8 => tokens.append_all(quote! { i8 }), | ||
| Self::I16 => tokens.append_all(quote! { i16 }), | ||
| Self::I32 => tokens.append_all(quote! { i32 }), | ||
| Self::I64 => tokens.append_all(quote! { i64 }), | ||
| Self::I128 => tokens.append_all(quote! { i128 }), | ||
| Self::U8 => tokens.append_all(quote! { u8 }), | ||
| Self::U16 => tokens.append_all(quote! { u16 }), | ||
| Self::U32 => tokens.append_all(quote! { u32 }), | ||
| Self::U64 => tokens.append_all(quote! { u64 }), | ||
| Self::U128 => tokens.append_all(quote! { u128 }), | ||
| Self::I8 => "i8", | ||
| Self::I16 => "i16", | ||
| Self::I32 => "i32", | ||
| Self::I64 => "i64", | ||
| Self::Isize => "isize", | ||
| Self::U8 => "u8", | ||
| Self::U16 => "u16", | ||
| Self::U32 => "u32", | ||
| Self::U64 => "u64", | ||
| Self::Usize => "usize", | ||
| } | ||
| } | ||
| } | ||
|
|
||
| #[derive(Clone, Copy)] | ||
| pub enum BaseRepr { | ||
| C, | ||
| // structs only | ||
| Transparent, | ||
| // enums only | ||
| Int(IntRepr), | ||
| } | ||
|
|
||
| impl ToTokens for BaseRepr { | ||
| impl ToTokens for Primitive { | ||
| fn to_tokens(&self, tokens: &mut TokenStream) { | ||
| match self { | ||
| BaseRepr::C => tokens.append_all(quote! { C }), | ||
| BaseRepr::Transparent => tokens.append_all(quote! { transparent }), | ||
| BaseRepr::Int(int_repr) => tokens.append_all(quote! { #int_repr }), | ||
| } | ||
| let ident = Ident::new(self.as_str(), Span::call_site()); | ||
| tokens.extend(quote! { #ident }); | ||
| } | ||
| } | ||
|
|
||
| #[derive(Clone)] | ||
| pub enum Modifier { | ||
| // structs only | ||
| Packed, | ||
| Align(LitInt), | ||
| Packed(#[allow(dead_code)] usize), | ||
| Align(#[allow(dead_code)] usize), | ||
| } | ||
|
|
||
| impl ToTokens for Modifier { | ||
| fn to_tokens(&self, tokens: &mut TokenStream) { | ||
| match self { | ||
| Modifier::Packed => tokens.append_all(quote! { packed }), | ||
| Modifier::Align(n) => tokens.append_all(quote! { align(#n) }), | ||
| } | ||
| } | ||
| } | ||
|
|
||
| #[derive(Clone, Default)] | ||
| pub struct Repr { | ||
| pub base_repr: Option<(BaseRepr, Span)>, | ||
| pub modifier: Option<(Modifier, Span)>, | ||
| pub enum Repr { | ||
| Transparent, | ||
| Primitive(Primitive), | ||
| C { | ||
| #[allow(dead_code)] | ||
| primitive: Option<Primitive>, | ||
| #[allow(dead_code)] | ||
| modifier: Option<Modifier>, | ||
| }, | ||
| Rust { | ||
| #[allow(dead_code)] | ||
| modifier: Option<Modifier>, | ||
| }, | ||
| } | ||
|
|
||
| impl Repr { | ||
| fn try_set_modifier<S: ToTokens>( | ||
| &mut self, | ||
| modifier: Modifier, | ||
| spanned: S, | ||
| ) -> Result<(), Error> { | ||
| if self.modifier.is_some() { | ||
| Err(Error::new_spanned( | ||
| spanned, | ||
| "only one repr modifier may be specified", | ||
| )) | ||
| } else { | ||
| self.modifier = Some((modifier, spanned.span())); | ||
| Ok(()) | ||
| pub fn from_attrs(attrs: &[Attribute]) -> Result<Self, Error> { | ||
| let mut c = false; | ||
| let mut transparent = false; | ||
| let mut primitive = None; | ||
| let mut modifier = None; | ||
|
|
||
| for attr in attrs.iter().filter(|a| a.meta.path().is_ident("repr")) { | ||
| attr.parse_nested_meta(|meta| { | ||
| if meta.path.is_ident("C") { | ||
| c = true; | ||
| Ok(()) | ||
| } else if meta.path.is_ident("transparent") { | ||
| transparent = true; | ||
| Ok(()) | ||
| } else if let Some(&p) = Primitive::ALL | ||
| .iter() | ||
| .find(|p| meta.path.is_ident(p.as_str())) | ||
| { | ||
| primitive = Some(p); | ||
| Ok(()) | ||
| } else if meta.path.is_ident("align") { | ||
| let content; | ||
| parenthesized!(content in meta.input); | ||
| let lit = content.parse::<LitInt>()?; | ||
| let n = lit.base10_parse()?; | ||
| modifier = Some(Modifier::Align(n)); | ||
| Ok(()) | ||
| } else if meta.path.is_ident("packed") { | ||
| if meta.input.peek(token::Paren) { | ||
| let content; | ||
| parenthesized!(content in meta.input); | ||
| let lit = content.parse::<LitInt>()?; | ||
| let n = lit.base10_parse()?; | ||
| modifier = Some(Modifier::Packed(n)); | ||
| } else { | ||
| modifier = Some(Modifier::Packed(1)); | ||
| } | ||
| Ok(()) | ||
| } else { | ||
| Err(Error::new_spanned( | ||
| meta.path, | ||
| "unrecognized repr argument", | ||
| )) | ||
| } | ||
| })?; | ||
| } | ||
| } | ||
|
|
||
| fn try_set_base_repr<S: ToTokens>( | ||
| &mut self, | ||
| repr: BaseRepr, | ||
| spanned: S, | ||
| ) -> Result<(), Error> { | ||
| if self.base_repr.is_some() { | ||
| Err(Error::new_spanned( | ||
| spanned, | ||
| "only one repr may be specified", | ||
| )) | ||
| if c { | ||
| Ok(Repr::C { | ||
| primitive, | ||
| modifier, | ||
| }) | ||
| } else if transparent { | ||
| Ok(Repr::Transparent) | ||
| } else if let Some(primitive) = primitive { | ||
| Ok(Repr::Primitive(primitive)) | ||
| } else { | ||
| self.base_repr = Some((repr, spanned.span())); | ||
| Ok(()) | ||
| Ok(Repr::Rust { modifier }) | ||
| } | ||
| } | ||
|
|
||
| pub fn parse_list_meta( | ||
| &mut self, | ||
| meta: ParseNestedMeta<'_>, | ||
| ) -> Result<(), Error> { | ||
| if meta.path.is_ident("packed") { | ||
| return self.try_set_modifier(Modifier::Packed, meta.path); | ||
| } else if meta.path.is_ident("align") { | ||
| let content; | ||
| parenthesized!(content in meta.input); | ||
| let alignment = content.parse()?; | ||
|
|
||
| if !content.is_empty() { | ||
| return Err(content.error("align requires only one argument")); | ||
| } | ||
|
|
||
| return self | ||
| .try_set_modifier(Modifier::Align(alignment), meta.path); | ||
| } | ||
|
|
||
| let parsed_repr = if meta.path.is_ident("transparent") { | ||
| BaseRepr::Transparent | ||
| } else if meta.path.is_ident("C") { | ||
| BaseRepr::C | ||
| } else if meta.path.is_ident("i8") { | ||
| BaseRepr::Int(IntRepr::I8) | ||
| } else if meta.path.is_ident("i16") { | ||
| BaseRepr::Int(IntRepr::I16) | ||
| } else if meta.path.is_ident("i32") { | ||
| BaseRepr::Int(IntRepr::I32) | ||
| } else if meta.path.is_ident("i64") { | ||
| BaseRepr::Int(IntRepr::I64) | ||
| } else if meta.path.is_ident("i128") { | ||
| BaseRepr::Int(IntRepr::I128) | ||
| } else if meta.path.is_ident("u8") { | ||
| BaseRepr::Int(IntRepr::U8) | ||
| } else if meta.path.is_ident("u16") { | ||
| BaseRepr::Int(IntRepr::U16) | ||
| } else if meta.path.is_ident("u32") { | ||
| BaseRepr::Int(IntRepr::U32) | ||
| } else if meta.path.is_ident("u64") { | ||
| BaseRepr::Int(IntRepr::U64) | ||
| } else if meta.path.is_ident("u128") { | ||
| BaseRepr::Int(IntRepr::U128) | ||
| } else { | ||
| let msg = | ||
| "invalid repr, available reprs are transparent, C, i* and u*"; | ||
|
|
||
| return Err(Error::new_spanned(meta.path, msg)); | ||
| }; | ||
|
|
||
| self.try_set_base_repr(parsed_repr, meta.path) | ||
| } | ||
| } | ||
|
|
||
| impl ToTokens for Repr { | ||
| fn to_tokens(&self, tokens: &mut TokenStream) { | ||
| let base_repr = self.base_repr.as_ref().map(|(b, _)| b); | ||
| let base_repr_iter = base_repr.iter(); | ||
| let modifier = self.modifier.as_ref().map(|(m, _)| m); | ||
| let modifier_iter = modifier.iter(); | ||
| tokens.append_all( | ||
| quote! { #[repr(#(#base_repr_iter,)* #(#modifier_iter,)*)] }, | ||
| ); | ||
| } | ||
| } |