From 4b0c3bff871eb6125835fd911891bf503c61c820 Mon Sep 17 00:00:00 2001
From: Jorge Aparicio <jorge@japaric.io>
Date: Thu, 6 Jul 2017 17:51:34 -0500
Subject: [PATCH] rtfm!: remove init.resources and make idle.local optional

---
 macros/src/syntax/mod.rs   |  1 -
 macros/src/syntax/parse.rs | 66 +++++++++++++++++++++++++-------------
 macros/src/trans.rs        | 32 +++++++-----------
 3 files changed, 56 insertions(+), 43 deletions(-)

diff --git a/macros/src/syntax/mod.rs b/macros/src/syntax/mod.rs
index c856617ea1..53c17a82d4 100644
--- a/macros/src/syntax/mod.rs
+++ b/macros/src/syntax/mod.rs
@@ -17,7 +17,6 @@ pub struct App {
 #[derive(Debug)]
 pub struct Init {
     pub path: Tokens,
-    pub resources: HashSet<Ident>,
 }
 
 #[derive(Debug)]
diff --git a/macros/src/syntax/parse.rs b/macros/src/syntax/parse.rs
index e6d3f461cd..9cfbd78bdd 100644
--- a/macros/src/syntax/parse.rs
+++ b/macros/src/syntax/parse.rs
@@ -1,7 +1,6 @@
 use std::collections::{HashMap, HashSet};
 
 use syn::{self, DelimToken, Ident, IntTy, Lit, Token, TokenTree};
-use quote::Tokens;
 
 use syntax::{App, Idle, Init, Kind, Resource, Resources, Task, Tasks};
 
@@ -136,10 +135,7 @@ pub fn app(input: &str) -> App {
     }
 }
 
-fn idle_init(
-    tts: Vec<TokenTree>,
-    allows_locals: bool,
-) -> (Option<Resources>, Tokens, HashSet<Ident>) {
+pub fn idle(tts: Vec<TokenTree>) -> Idle {
     let mut tts = tts.into_iter();
 
     let mut local = None;
@@ -161,7 +157,7 @@ fn idle_init(
         );
 
         match id.as_ref() {
-            "local" if allows_locals => {
+            "local" => {
                 assert!(local.is_none(), "duplicated local field");
 
                 let tt = tts.next();
@@ -183,7 +179,8 @@ fn idle_init(
 
                 let mut pieces = vec![];
                 loop {
-                    let tt = tts.next().expect("expected comma, found EOM");
+                    let tt = tts.next()
+                        .expect("expected comma, found end of macro");
 
                     if tt == TokenTree::Token(Token::Comma) {
                         path = Some(quote!(#(#pieces)*));
@@ -225,27 +222,52 @@ fn idle_init(
         );
     }
 
-    (
-        local,
-        path.expect("path field is missing"),
-        resources.unwrap_or(HashSet::new()),
-    )
-}
-
-pub fn idle(tts: Vec<TokenTree>) -> Idle {
-    let (locals, path, resources) = idle_init(tts, true);
-
     Idle {
-        local: locals.expect("local field is missing"),
-        path,
-        resources,
+        local: local.unwrap_or(HashMap::new()),
+        path: path.expect("path field is missing"),
+        resources: resources.unwrap_or(HashSet::new()),
     }
 }
 
 pub fn init(tts: Vec<TokenTree>) -> Init {
-    let (_, path, resources) = idle_init(tts, false);
+    let mut tts = tts.into_iter();
 
-    Init { path, resources }
+    let mut path = None;
+    while let Some(tt) = tts.next() {
+        let id = if let TokenTree::Token(Token::Ident(id)) = tt {
+            id
+        } else {
+            panic!("expected ident, found {:?}", tt);
+        };
+
+        let tt = tts.next();
+        assert_eq!(
+            tt,
+            Some(TokenTree::Token(Token::Colon)),
+            "expected colon, found {:?}",
+            tt
+        );
+
+        match id.as_ref() {
+            "path" => {
+                let mut pieces = vec![];
+                loop {
+                    let tt = tts.next()
+                        .expect("expected comma, found end of macro");
+
+                    if tt == TokenTree::Token(Token::Comma) {
+                        path = Some(quote!(#(#pieces)*));
+                        break;
+                    } else {
+                        pieces.push(tt);
+                    }
+                }
+            }
+            id => panic!("unexpected field {}", id),
+        }
+    }
+
+    Init { path: path.expect("path field is missing") }
 }
 
 fn idents(tts: Vec<TokenTree>) -> HashSet<Ident> {
diff --git a/macros/src/trans.rs b/macros/src/trans.rs
index 6cf3a51750..14d24fd81c 100644
--- a/macros/src/trans.rs
+++ b/macros/src/trans.rs
@@ -33,32 +33,24 @@ fn init(app: &App, main: &mut Vec<Tokens>, root: &mut Vec<Tokens>) {
     let mut fields = vec![];
     let mut exprs = vec![];
     let mut lifetime = None;
-    for name in &app.init.resources {
+    for (name, resource) in &app.resources {
         lifetime = Some(quote!('a));
 
-        if let Some(resource) = app.resources.get(name) {
-            let ty = &resource.ty;
+        let ty = &resource.ty;
 
-            fields.push(quote! {
-                pub #name: &'a mut #ty,
-            });
+        fields.push(quote! {
+            pub #name: &'a mut #ty,
+        });
 
-            exprs.push(quote! {
-                #name: &mut *super::#name.get(),
-            });
-        } else {
-            fields.push(quote! {
-                pub #name: &'a mut ::#device::#name,
-            });
-
-            exprs.push(quote! {
-                #name: &mut *::#device::#name.get(),
-            });
-        }
+        exprs.push(quote! {
+            #name: &mut *super::#name.get(),
+        });
     }
 
     root.push(quote! {
         mod init {
+            pub use ::#device::Peripherals;
+
             #[allow(non_snake_case)]
             pub struct Resources<#lifetime> {
                 #(#fields)*
@@ -122,10 +114,10 @@ fn init(app: &App, main: &mut Vec<Tokens>, root: &mut Vec<Tokens>) {
     let init = &app.init.path;
     main.push(quote! {
         // type check
-        let init: fn(init::Resources) = #init;
+        let init: fn(init::Peripherals, init::Resources) = #init;
 
         #krate::atomic(|cs| unsafe {
-            init(init::Resources::new());
+            init(init::Peripherals::all(), init::Resources::new());
 
             #(#exceptions)*
             #(#interrupts)*