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#![recursion_limit = "1024"]
extern crate proc_macro;
use proc_macro2;
use quote::quote;
use proc_macro::TokenStream;
fn impl_field(ident: &proc_macro2::TokenStream, ty: &syn::Type) -> proc_macro2::TokenStream {
match *ty {
syn::Type::Array(ref array) => match array.len {
syn::Expr::Lit(syn::ExprLit {
lit: syn::Lit::Int(ref int),
..
}) => {
let size = int.base10_parse::<usize>().unwrap();
quote! {
#ident: { let mut __tmp: #ty = [0u8.into(); #size]; src.gread_inout_with(offset, &mut __tmp, ctx)?; __tmp }
}
}
_ => panic!("Pread derive with bad array constexpr"),
},
syn::Type::Group(ref group) => impl_field(ident, &group.elem),
_ => {
quote! {
#ident: src.gread_with::<#ty>(offset, ctx)?
}
}
}
}
fn impl_struct(
name: &syn::Ident,
fields: &syn::punctuated::Punctuated<syn::Field, syn::Token![,]>,
generics: &syn::Generics,
) -> proc_macro2::TokenStream {
let items: Vec<_> = fields
.iter()
.enumerate()
.map(|(i, f)| {
let ident = &f.ident.as_ref().map(|i| quote! {#i}).unwrap_or({
let t = proc_macro2::Literal::usize_unsuffixed(i);
quote! {#t}
});
let ty = &f.ty;
impl_field(ident, ty)
})
.collect();
let gl = &generics.lt_token;
let gp = &generics.params;
let gg = &generics.gt_token;
let gn = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! { #ident }
}
p => quote! { #p },
});
let gn = quote! { #gl #( #gn ),* #gg };
let gw = if !gp.is_empty() {
let gi = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! {
#ident : ::scroll::ctx::TryFromCtx<'a, ::scroll::Endian> + ::std::convert::From<u8> + ::std::marker::Copy,
::scroll::Error : ::std::convert::From<< #ident as ::scroll::ctx::TryFromCtx<'a, ::scroll::Endian>>::Error>,
< #ident as ::scroll::ctx::TryFromCtx<'a, ::scroll::Endian>>::Error : ::std::convert::From<scroll::Error>
}
},
p => quote! { #p }
});
quote! { #( #gi ),* , }
} else {
quote! {}
};
quote! {
impl<'a, #gp > ::scroll::ctx::TryFromCtx<'a, ::scroll::Endian> for #name #gn where #gw #name #gn : 'a {
type Error = ::scroll::Error;
#[inline]
fn try_from_ctx(src: &'a [u8], ctx: ::scroll::Endian) -> ::scroll::export::result::Result<(Self, usize), Self::Error> {
use ::scroll::Pread;
let offset = &mut 0;
let data = Self { #(#items,)* };
Ok((data, *offset))
}
}
}
}
fn impl_try_from_ctx(ast: &syn::DeriveInput) -> proc_macro2::TokenStream {
let name = &ast.ident;
let generics = &ast.generics;
match ast.data {
syn::Data::Struct(ref data) => match data.fields {
syn::Fields::Named(ref fields) => impl_struct(name, &fields.named, generics),
syn::Fields::Unnamed(ref fields) => impl_struct(name, &fields.unnamed, generics),
_ => {
panic!("Pread can not be derived for unit structs")
}
},
_ => panic!("Pread can only be derived for structs"),
}
}
#[proc_macro_derive(Pread)]
pub fn derive_pread(input: TokenStream) -> TokenStream {
let ast: syn::DeriveInput = syn::parse(input).unwrap();
let gen = impl_try_from_ctx(&ast);
gen.into()
}
fn impl_pwrite_field(ident: &proc_macro2::TokenStream, ty: &syn::Type) -> proc_macro2::TokenStream {
match ty {
syn::Type::Array(ref array) => match array.len {
syn::Expr::Lit(syn::ExprLit {
lit: syn::Lit::Int(ref int),
..
}) => {
let size = int.base10_parse::<usize>().unwrap();
quote! {
for i in 0..#size {
dst.gwrite_with(&self.#ident[i], offset, ctx)?;
}
}
}
_ => panic!("Pwrite derive with bad array constexpr"),
},
syn::Type::Group(group) => impl_pwrite_field(ident, &group.elem),
_ => {
quote! {
dst.gwrite_with(&self.#ident, offset, ctx)?
}
}
}
}
fn impl_try_into_ctx(
name: &syn::Ident,
fields: &syn::punctuated::Punctuated<syn::Field, syn::Token![,]>,
generics: &syn::Generics,
) -> proc_macro2::TokenStream {
let items: Vec<_> = fields
.iter()
.enumerate()
.map(|(i, f)| {
let ident = &f.ident.as_ref().map(|i| quote! {#i}).unwrap_or({
let t = proc_macro2::Literal::usize_unsuffixed(i);
quote! {#t}
});
let ty = &f.ty;
impl_pwrite_field(ident, ty)
})
.collect();
let gl = &generics.lt_token;
let gp = &generics.params;
let gg = &generics.gt_token;
let gn = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! { #ident }
}
p => quote! { #p },
});
let gn = quote! { #gl #( #gn ),* #gg };
let gwref = if !gp.is_empty() {
let gi = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! {
&'a #ident : ::scroll::ctx::TryIntoCtx<::scroll::Endian>,
::scroll::Error: ::std::convert::From<<&'a #ident as ::scroll::ctx::TryIntoCtx<::scroll::Endian>>::Error>,
<&'a #ident as ::scroll::ctx::TryIntoCtx<::scroll::Endian>>::Error: ::std::convert::From<scroll::Error>
}
},
p => quote! { #p }
});
quote! { where #( #gi ),* }
} else {
quote! {}
};
let gw = if !gp.is_empty() {
let gi = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! {
#ident : ::scroll::ctx::TryIntoCtx<::scroll::Endian>,
::scroll::Error: ::std::convert::From<<#ident as ::scroll::ctx::TryIntoCtx<::scroll::Endian>>::Error>,
<#ident as ::scroll::ctx::TryIntoCtx<::scroll::Endian>>::Error: ::std::convert::From<scroll::Error>
}
},
p => quote! { #p }
});
quote! { where Self: ::std::marker::Copy, #( #gi ),* }
} else {
quote! {}
};
quote! {
impl<'a, #gp > ::scroll::ctx::TryIntoCtx<::scroll::Endian> for &'a #name #gn #gwref {
type Error = ::scroll::Error;
#[inline]
fn try_into_ctx(self, dst: &mut [u8], ctx: ::scroll::Endian) -> ::scroll::export::result::Result<usize, Self::Error> {
use ::scroll::Pwrite;
let offset = &mut 0;
#(#items;)*;
Ok(*offset)
}
}
impl #gl #gp #gg ::scroll::ctx::TryIntoCtx<::scroll::Endian> for #name #gn #gw {
type Error = ::scroll::Error;
#[inline]
fn try_into_ctx(self, dst: &mut [u8], ctx: ::scroll::Endian) -> ::scroll::export::result::Result<usize, Self::Error> {
(&self).try_into_ctx(dst, ctx)
}
}
}
}
fn impl_pwrite(ast: &syn::DeriveInput) -> proc_macro2::TokenStream {
let name = &ast.ident;
let generics = &ast.generics;
match ast.data {
syn::Data::Struct(ref data) => match data.fields {
syn::Fields::Named(ref fields) => impl_try_into_ctx(name, &fields.named, generics),
syn::Fields::Unnamed(ref fields) => impl_try_into_ctx(name, &fields.unnamed, generics),
_ => {
panic!("Pwrite can not be derived for unit structs")
}
},
_ => panic!("Pwrite can only be derived for structs"),
}
}
#[proc_macro_derive(Pwrite)]
pub fn derive_pwrite(input: TokenStream) -> TokenStream {
let ast: syn::DeriveInput = syn::parse(input).unwrap();
let gen = impl_pwrite(&ast);
gen.into()
}
fn size_with(
name: &syn::Ident,
fields: &syn::punctuated::Punctuated<syn::Field, syn::Token![,]>,
generics: &syn::Generics,
) -> proc_macro2::TokenStream {
let items: Vec<_> = fields
.iter()
.map(|f| {
let ty = &f.ty;
match *ty {
syn::Type::Array(ref array) => {
let elem = &array.elem;
match array.len {
syn::Expr::Lit(syn::ExprLit {
lit: syn::Lit::Int(ref int),
..
}) => {
let size = int.base10_parse::<usize>().unwrap();
quote! {
(#size * <#elem>::size_with(ctx))
}
}
_ => panic!("Pread derive with bad array constexpr"),
}
}
_ => {
quote! {
<#ty>::size_with(ctx)
}
}
}
})
.collect();
let gl = &generics.lt_token;
let gp = &generics.params;
let gg = &generics.gt_token;
let gn = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! { #ident }
}
p => quote! { #p },
});
let gn = quote! { #gl #( #gn ),* #gg };
let gw = if !gp.is_empty() {
let gi = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! {
#ident : ::scroll::ctx::SizeWith<::scroll::Endian>
}
}
p => quote! { #p },
});
quote! { where #( #gi ),* }
} else {
quote! {}
};
quote! {
impl #gl #gp #gg ::scroll::ctx::SizeWith<::scroll::Endian> for #name #gn #gw {
#[inline]
fn size_with(ctx: &::scroll::Endian) -> usize {
0 #(+ #items)*
}
}
}
}
fn impl_size_with(ast: &syn::DeriveInput) -> proc_macro2::TokenStream {
let name = &ast.ident;
let generics = &ast.generics;
match ast.data {
syn::Data::Struct(ref data) => match data.fields {
syn::Fields::Named(ref fields) => size_with(name, &fields.named, generics),
syn::Fields::Unnamed(ref fields) => size_with(name, &fields.unnamed, generics),
_ => {
panic!("SizeWith can not be derived for unit structs")
}
},
_ => panic!("SizeWith can only be derived for structs"),
}
}
#[proc_macro_derive(SizeWith)]
pub fn derive_sizewith(input: TokenStream) -> TokenStream {
let ast: syn::DeriveInput = syn::parse(input).unwrap();
let gen = impl_size_with(&ast);
gen.into()
}
fn impl_cread_struct(
name: &syn::Ident,
fields: &syn::punctuated::Punctuated<syn::Field, syn::Token![,]>,
generics: &syn::Generics,
) -> proc_macro2::TokenStream {
let items: Vec<_> = fields.iter().enumerate().map(|(i, f)| {
let ident = &f.ident.as_ref().map(|i|quote!{#i}).unwrap_or({let t = proc_macro2::Literal::usize_unsuffixed(i); quote!{#t}});
let ty = &f.ty;
match *ty {
syn::Type::Array(ref array) => {
let arrty = &array.elem;
match array.len {
syn::Expr::Lit(syn::ExprLit { lit: syn::Lit::Int(ref int), ..}) => {
let size = int.base10_parse::<usize>().unwrap();
let incr = quote! { ::scroll::export::mem::size_of::<#arrty>() };
quote! {
#ident: {
let mut __tmp: #ty = [0u8.into(); #size];
for i in 0..__tmp.len() {
__tmp[i] = src.cread_with(*offset, ctx);
*offset += #incr;
}
__tmp
}
}
},
_ => panic!("IOread derive with bad array constexpr")
}
},
_ => {
let size = quote! { ::scroll::export::mem::size_of::<#ty>() };
quote! {
#ident: { let res = src.cread_with::<#ty>(*offset, ctx); *offset += #size; res }
}
}
}
}).collect();
let gl = &generics.lt_token;
let gp = &generics.params;
let gg = &generics.gt_token;
let gn = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! { #ident }
}
p => quote! { #p },
});
let gn = quote! { #gl #( #gn ),* #gg };
let gw = if !gp.is_empty() {
let gi = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! {
#ident : ::scroll::ctx::FromCtx<::scroll::Endian> + ::std::convert::From<u8> + ::std::marker::Copy
}
},
p => quote! { #p }
});
quote! { where #( #gi ),* , }
} else {
quote! {}
};
quote! {
impl #gl #gp #gg ::scroll::ctx::FromCtx<::scroll::Endian> for #name #gn #gw {
#[inline]
fn from_ctx(src: &[u8], ctx: ::scroll::Endian) -> Self {
use ::scroll::Cread;
let offset = &mut 0;
let data = Self { #(#items,)* };
data
}
}
}
}
fn impl_from_ctx(ast: &syn::DeriveInput) -> proc_macro2::TokenStream {
let name = &ast.ident;
let generics = &ast.generics;
match ast.data {
syn::Data::Struct(ref data) => match data.fields {
syn::Fields::Named(ref fields) => impl_cread_struct(name, &fields.named, generics),
syn::Fields::Unnamed(ref fields) => impl_cread_struct(name, &fields.unnamed, generics),
_ => {
panic!("IOread can not be derived for unit structs")
}
},
_ => panic!("IOread can only be derived for structs"),
}
}
#[proc_macro_derive(IOread)]
pub fn derive_ioread(input: TokenStream) -> TokenStream {
let ast: syn::DeriveInput = syn::parse(input).unwrap();
let gen = impl_from_ctx(&ast);
gen.into()
}
fn impl_into_ctx(
name: &syn::Ident,
fields: &syn::punctuated::Punctuated<syn::Field, syn::Token![,]>,
generics: &syn::Generics,
) -> proc_macro2::TokenStream {
let items: Vec<_> = fields
.iter()
.enumerate()
.map(|(i, f)| {
let ident = &f.ident.as_ref().map(|i| quote! {#i}).unwrap_or({
let t = proc_macro2::Literal::usize_unsuffixed(i);
quote! {#t}
});
let ty = &f.ty;
let size = quote! { ::scroll::export::mem::size_of::<#ty>() };
match *ty {
syn::Type::Array(ref array) => {
let arrty = &array.elem;
quote! {
let size = ::scroll::export::mem::size_of::<#arrty>();
for i in 0..self.#ident.len() {
dst.cwrite_with(self.#ident[i], *offset, ctx);
*offset += size;
}
}
}
_ => {
quote! {
dst.cwrite_with(self.#ident, *offset, ctx);
*offset += #size;
}
}
}
})
.collect();
let gl = &generics.lt_token;
let gp = &generics.params;
let gg = &generics.gt_token;
let gn = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! { #ident }
}
p => quote! { #p },
});
let gw = if !gp.is_empty() {
let gi = gp.iter().map(|param: &syn::GenericParam| match param {
syn::GenericParam::Type(ref t) => {
let ident = &t.ident;
quote! {
#ident : ::scroll::ctx::IntoCtx<::scroll::Endian> + ::std::marker::Copy
}
}
p => quote! { #p },
});
quote! { where #( #gi ),* }
} else {
quote! {}
};
let gn = quote! { #gl #( #gn ),* #gg };
quote! {
impl<'a, #gp > ::scroll::ctx::IntoCtx<::scroll::Endian> for &'a #name #gn #gw {
#[inline]
fn into_ctx(self, dst: &mut [u8], ctx: ::scroll::Endian) {
use ::scroll::Cwrite;
let offset = &mut 0;
#(#items;)*;
()
}
}
impl #gl #gp #gg ::scroll::ctx::IntoCtx<::scroll::Endian> for #name #gn #gw {
#[inline]
fn into_ctx(self, dst: &mut [u8], ctx: ::scroll::Endian) {
(&self).into_ctx(dst, ctx)
}
}
}
}
fn impl_iowrite(ast: &syn::DeriveInput) -> proc_macro2::TokenStream {
let name = &ast.ident;
let generics = &ast.generics;
match ast.data {
syn::Data::Struct(ref data) => match data.fields {
syn::Fields::Named(ref fields) => impl_into_ctx(name, &fields.named, generics),
syn::Fields::Unnamed(ref fields) => impl_into_ctx(name, &fields.unnamed, generics),
_ => {
panic!("IOwrite can not be derived for unit structs")
}
},
_ => panic!("IOwrite can only be derived for structs"),
}
}
#[proc_macro_derive(IOwrite)]
pub fn derive_iowrite(input: TokenStream) -> TokenStream {
let ast: syn::DeriveInput = syn::parse(input).unwrap();
let gen = impl_iowrite(&ast);
gen.into()
}