Started work

macros/src/codegen/local_resources_struct.rs

@@ -0,0 +1,88 @@
+use proc_macro2::TokenStream as TokenStream2;
+use quote::quote;
+use rtic_syntax::{ast::App, Context};
+
+use crate::codegen::util;
+
+/// Generates local resources structs
+pub fn codegen(ctxt: Context, needs_lt: &mut bool, app: &App) -> (TokenStream2, TokenStream2) {
+    let mut lt = None;
+
+    let resources = match ctxt {
+        Context::Init => &app.init.args.local_resources,
+        Context::Idle => &app.idle.unwrap().args.local_resources,
+        Context::HardwareTask(name) => &app.hardware_tasks[name].args.local_resources,
+        Context::SoftwareTask(name) => &app.software_tasks[name].args.local_resources,
+    };
+
+    let mut fields = vec![];
+    let mut values = vec![];
+    let mut has_cfgs = false;
+
+    for (name, task_local) in resources {
+        let res = app.local_resources.get(name).expect("UNREACHABLE");
+
+        let cfgs = &res.cfgs;
+        has_cfgs |= !cfgs.is_empty();
+
+        let lt = if ctxt.runs_once() {
+            quote!('static)
+        } else {
+            lt = Some(quote!('a));
+            quote!('a)
+        };
+
+        let ty = &res.ty;
+        let mangled_name = util::mark_internal_ident(&name);
+
+        fields.push(quote!(
+            #(#cfgs)*
+            pub #name: &#lt mut #ty
+        ));
+
+        let expr = quote!(&mut *#mangled_name.get_mut_unchecked().as_mut_ptr());
+
+        values.push(quote!(
+            #(#cfgs)*
+            #name: #expr
+        ));
+    }
+
+    if lt.is_some() {
+        *needs_lt = true;
+
+        // The struct could end up empty due to `cfg`s leading to an error due to `'a` being unused
+        if has_cfgs {
+            fields.push(quote!(
+                #[doc(hidden)]
+                pub __marker__: core::marker::PhantomData<&'a ()>
+            ));
+
+            values.push(quote!(__marker__: core::marker::PhantomData))
+        }
+    }
+
+    let doc = format!("Local resources `{}` has access to", ctxt.ident(app));
+    let ident = util::local_resources_ident(ctxt, app);
+    let ident = util::mark_internal_ident(&ident);
+    let item = quote!(
+        #[allow(non_snake_case)]
+        #[doc = #doc]
+        pub struct #ident<#lt> {
+            #(#fields,)*
+        }
+    );
+
+    let constructor = quote!(
+        impl<#lt> #ident<#lt> {
+            #[inline(always)]
+            pub unsafe fn new() -> Self {
+                #ident {
+                    #(#values,)*
+                }
+            }
+        }
+    );
+
+    (item, constructor)
+}