embassy/embassy-macros/src/lib.rs
Dario Nieuwenhuis a2e7c24e00 Clippy fixes
2021-10-18 01:05:29 +02:00

533 lines
15 KiB
Rust

#![feature(proc_macro_diagnostic)]
extern crate proc_macro;
use darling::FromMeta;
use proc_macro::TokenStream;
use proc_macro2::Span;
use quote::{format_ident, quote};
use std::iter;
use syn::spanned::Spanned;
use syn::{parse, Type, Visibility};
use syn::{ItemFn, ReturnType};
mod path;
use path::ModulePrefix;
#[derive(Debug, FromMeta)]
struct TaskArgs {
#[darling(default)]
pool_size: Option<usize>,
#[darling(default)]
send: bool,
#[darling(default)]
embassy_prefix: ModulePrefix,
}
#[proc_macro_attribute]
pub fn task(args: TokenStream, item: TokenStream) -> TokenStream {
let macro_args = syn::parse_macro_input!(args as syn::AttributeArgs);
let mut task_fn = syn::parse_macro_input!(item as syn::ItemFn);
let macro_args = match TaskArgs::from_list(&macro_args) {
Ok(v) => v,
Err(e) => {
return TokenStream::from(e.write_errors());
}
};
let embassy_prefix = macro_args.embassy_prefix.append("embassy");
let embassy_path = embassy_prefix.path();
let pool_size: usize = macro_args.pool_size.unwrap_or(1);
let mut fail = false;
if task_fn.sig.asyncness.is_none() {
task_fn
.sig
.span()
.unwrap()
.error("task functions must be async")
.emit();
fail = true;
}
if !task_fn.sig.generics.params.is_empty() {
task_fn
.sig
.span()
.unwrap()
.error("task functions must not be generic")
.emit();
fail = true;
}
if pool_size < 1 {
return parse::Error::new(Span::call_site(), "pool_size must be 1 or greater")
.to_compile_error()
.into();
}
let mut arg_names: syn::punctuated::Punctuated<syn::Ident, syn::Token![,]> =
syn::punctuated::Punctuated::new();
let mut args = task_fn.sig.inputs.clone();
for arg in args.iter_mut() {
match arg {
syn::FnArg::Receiver(_) => {
arg.span()
.unwrap()
.error("task functions must not have receiver arguments")
.emit();
fail = true;
}
syn::FnArg::Typed(t) => match t.pat.as_mut() {
syn::Pat::Ident(i) => {
arg_names.push(i.ident.clone());
i.mutability = None;
}
_ => {
arg.span()
.unwrap()
.error("pattern matching in task arguments is not yet supporteds")
.emit();
fail = true;
}
},
}
}
if fail {
return TokenStream::new();
}
let name = task_fn.sig.ident.clone();
let visibility = &task_fn.vis;
task_fn.sig.ident = format_ident!("task");
let impl_ty = if macro_args.send {
quote!(impl ::core::future::Future + Send + 'static)
} else {
quote!(impl ::core::future::Future + 'static)
};
let attrs = &task_fn.attrs;
let result = quote! {
#(#attrs)*
#visibility fn #name(#args) -> #embassy_path::executor::SpawnToken<#impl_ty> {
use #embassy_path::executor::raw::TaskStorage;
#task_fn
type F = #impl_ty;
#[allow(clippy::declare_interior_mutable_const)]
const NEW_TASK: TaskStorage<F> = TaskStorage::new();
static POOL: [TaskStorage<F>; #pool_size] = [NEW_TASK; #pool_size];
unsafe { TaskStorage::spawn_pool(&POOL, move || task(#arg_names)) }
}
};
result.into()
}
#[proc_macro_attribute]
pub fn interrupt(args: TokenStream, input: TokenStream) -> TokenStream {
let mut f: ItemFn = syn::parse(input).expect("`#[interrupt]` must be applied to a function");
if !args.is_empty() {
return parse::Error::new(Span::call_site(), "This attribute accepts no arguments")
.to_compile_error()
.into();
}
let fspan = f.span();
let ident = f.sig.ident.clone();
let ident_s = ident.to_string();
// XXX should we blacklist other attributes?
let valid_signature = f.sig.constness.is_none()
&& f.vis == Visibility::Inherited
&& f.sig.abi.is_none()
&& f.sig.inputs.is_empty()
&& f.sig.generics.params.is_empty()
&& f.sig.generics.where_clause.is_none()
&& f.sig.variadic.is_none()
&& match f.sig.output {
ReturnType::Default => true,
ReturnType::Type(_, ref ty) => match **ty {
Type::Tuple(ref tuple) => tuple.elems.is_empty(),
Type::Never(..) => true,
_ => false,
},
};
if !valid_signature {
return parse::Error::new(
fspan,
"`#[interrupt]` handlers must have signature `[unsafe] fn() [-> !]`",
)
.to_compile_error()
.into();
}
f.block.stmts = iter::once(
syn::parse2(quote! {{
// Check that this interrupt actually exists
let __irq_exists_check: interrupt::#ident;
}})
.unwrap(),
)
.chain(f.block.stmts)
.collect();
quote!(
#[doc(hidden)]
#[export_name = #ident_s]
#[allow(non_snake_case)]
#f
)
.into()
}
#[proc_macro]
pub fn interrupt_declare(item: TokenStream) -> TokenStream {
let name = syn::parse_macro_input!(item as syn::Ident);
let name = format_ident!("{}", name);
let name_interrupt = format_ident!("{}", name);
let name_handler = format!("__EMBASSY_{}_HANDLER", name);
let result = quote! {
#[allow(non_camel_case_types)]
pub struct #name_interrupt(());
unsafe impl ::embassy::interrupt::Interrupt for #name_interrupt {
type Priority = crate::interrupt::Priority;
fn number(&self) -> u16 {
use cortex_m::interrupt::InterruptNumber;
let irq = InterruptEnum::#name;
irq.number() as u16
}
unsafe fn steal() -> Self {
Self(())
}
unsafe fn __handler(&self) -> &'static ::embassy::interrupt::Handler {
#[export_name = #name_handler]
static HANDLER: ::embassy::interrupt::Handler = ::embassy::interrupt::Handler::new();
&HANDLER
}
}
unsafe impl ::embassy::util::Unborrow for #name_interrupt {
type Target = #name_interrupt;
unsafe fn unborrow(self) -> #name_interrupt {
self
}
}
};
result.into()
}
#[proc_macro]
pub fn interrupt_take(item: TokenStream) -> TokenStream {
let name = syn::parse_macro_input!(item as syn::Ident);
let name = format!("{}", name);
let name_interrupt = format_ident!("{}", name);
let name_handler = format!("__EMBASSY_{}_HANDLER", name);
let result = quote! {
{
#[allow(non_snake_case)]
#[export_name = #name]
pub unsafe extern "C" fn trampoline() {
extern "C" {
#[link_name = #name_handler]
static HANDLER: ::embassy::interrupt::Handler;
}
let func = HANDLER.func.load(::embassy::export::atomic::Ordering::Relaxed);
let ctx = HANDLER.ctx.load(::embassy::export::atomic::Ordering::Relaxed);
let func: fn(*mut ()) = ::core::mem::transmute(func);
func(ctx)
}
static TAKEN: ::embassy::export::atomic::AtomicBool = ::embassy::export::atomic::AtomicBool::new(false);
if TAKEN.compare_exchange(false, true, ::embassy::export::atomic::Ordering::AcqRel, ::embassy::export::atomic::Ordering::Acquire).is_err() {
panic!("IRQ Already taken");
}
let irq: interrupt::#name_interrupt = unsafe { ::core::mem::transmute(()) };
irq
}
};
result.into()
}
#[cfg(feature = "stm32")]
#[path = "chip/stm32.rs"]
mod chip;
#[cfg(feature = "nrf")]
#[path = "chip/nrf.rs"]
mod chip;
#[cfg(feature = "rp")]
#[path = "chip/rp.rs"]
mod chip;
#[derive(Debug, FromMeta)]
struct MainArgs {
#[darling(default)]
embassy_prefix: ModulePrefix,
#[darling(default)]
config: Option<syn::LitStr>,
}
#[cfg(any(feature = "nrf", feature = "rp", feature = "stm32"))]
#[proc_macro_attribute]
pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
let macro_args = syn::parse_macro_input!(args as syn::AttributeArgs);
let task_fn = syn::parse_macro_input!(item as syn::ItemFn);
let macro_args = match MainArgs::from_list(&macro_args) {
Ok(v) => v,
Err(e) => {
return TokenStream::from(e.write_errors());
}
};
let mut fail = false;
if task_fn.sig.asyncness.is_none() {
task_fn
.sig
.span()
.unwrap()
.error("task functions must be async")
.emit();
fail = true;
}
if !task_fn.sig.generics.params.is_empty() {
task_fn
.sig
.span()
.unwrap()
.error("main function must not be generic")
.emit();
fail = true;
}
let args = task_fn.sig.inputs.clone();
if args.len() != 2 {
task_fn
.sig
.span()
.unwrap()
.error("main function must have 2 arguments")
.emit();
fail = true;
}
if fail {
return TokenStream::new();
}
let embassy_prefix = macro_args.embassy_prefix;
let embassy_prefix_lit = embassy_prefix.literal();
let embassy_path = embassy_prefix.append("embassy").path();
let task_fn_body = task_fn.block;
let config = macro_args
.config
.map(|s| s.parse::<syn::Expr>().unwrap())
.unwrap_or_else(|| {
syn::Expr::Verbatim(quote! {
Default::default()
})
});
let chip_setup = chip::generate(&embassy_prefix, config);
let result = quote! {
#[#embassy_path::task(embassy_prefix = #embassy_prefix_lit)]
async fn __embassy_main(#args) {
#task_fn_body
}
#[cortex_m_rt::entry]
fn main() -> ! {
unsafe fn make_static<T>(t: &mut T) -> &'static mut T {
::core::mem::transmute(t)
}
let mut executor = #embassy_path::executor::Executor::new();
let executor = unsafe { make_static(&mut executor) };
#chip_setup
executor.run(|spawner| {
spawner.must_spawn(__embassy_main(spawner, p));
})
}
};
result.into()
}
#[cfg(feature = "std")]
#[proc_macro_attribute]
pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
let macro_args = syn::parse_macro_input!(args as syn::AttributeArgs);
let task_fn = syn::parse_macro_input!(item as syn::ItemFn);
let macro_args = match MainArgs::from_list(&macro_args) {
Ok(v) => v,
Err(e) => {
return TokenStream::from(e.write_errors());
}
};
let embassy_path = macro_args.embassy_prefix.append("embassy");
let mut fail = false;
if task_fn.sig.asyncness.is_none() {
task_fn
.sig
.span()
.unwrap()
.error("task functions must be async")
.emit();
fail = true;
}
if !task_fn.sig.generics.params.is_empty() {
task_fn
.sig
.span()
.unwrap()
.error("main function must not be generic")
.emit();
fail = true;
}
let args = task_fn.sig.inputs.clone();
if args.len() != 1 {
task_fn
.sig
.span()
.unwrap()
.error("main function must have one argument")
.emit();
fail = true;
}
if fail {
return TokenStream::new();
}
let task_fn_body = task_fn.block.clone();
let embassy_path = embassy_path.path();
let embassy_prefix_lit = macro_args.embassy_prefix.literal();
let result = quote! {
#[#embassy_path::task(embassy_prefix = #embassy_prefix_lit)]
async fn __embassy_main(#args) {
#task_fn_body
}
fn main() -> ! {
unsafe fn make_static<T>(t: &mut T) -> &'static mut T {
::core::mem::transmute(t)
}
let mut executor = #embassy_path::executor::Executor::new();
let executor = unsafe { make_static(&mut executor) };
executor.run(|spawner| {
spawner.spawn(__embassy_main(spawner)).unwrap();
})
}
};
result.into()
}
#[cfg(feature = "wasm")]
#[proc_macro_attribute]
pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
let macro_args = syn::parse_macro_input!(args as syn::AttributeArgs);
let task_fn = syn::parse_macro_input!(item as syn::ItemFn);
let macro_args = match MainArgs::from_list(&macro_args) {
Ok(v) => v,
Err(e) => {
return TokenStream::from(e.write_errors());
}
};
let embassy_path = macro_args.embassy_prefix.append("embassy");
let mut fail = false;
if task_fn.sig.asyncness.is_none() {
task_fn
.sig
.span()
.unwrap()
.error("task functions must be async")
.emit();
fail = true;
}
if !task_fn.sig.generics.params.is_empty() {
task_fn
.sig
.span()
.unwrap()
.error("main function must not be generic")
.emit();
fail = true;
}
let args = task_fn.sig.inputs.clone();
if args.len() != 1 {
task_fn
.sig
.span()
.unwrap()
.error("main function must have one argument")
.emit();
fail = true;
}
if fail {
return TokenStream::new();
}
let task_fn_body = task_fn.block.clone();
let embassy_path = embassy_path.path();
let embassy_prefix_lit = macro_args.embassy_prefix.literal();
let result = quote! {
#[#embassy_path::task(embassy_prefix = #embassy_prefix_lit)]
async fn __embassy_main(#args) {
#task_fn_body
}
use wasm_bindgen::prelude::*;
#[wasm_bindgen(start)]
pub fn main() -> Result<(), JsValue> {
static EXECUTOR: #embassy_path::util::Forever<#embassy_path::executor::Executor> = #embassy_path::util::Forever::new();
let executor = EXECUTOR.put(#embassy_path::executor::Executor::new());
executor.start(|spawner| {
spawner.spawn(__embassy_main(spawner)).unwrap();
});
Ok(())
}
};
result.into()
}