1 files changed, 121 insertions, 0 deletions
diff --git a/rtic-macros/src/syntax.rs b/rtic-macros/src/syntax.rs
new file mode 100644
index 00000000..d6f5a476
--- /dev/null
+++ b/rtic-macros/src/syntax.rs
@@ -0,0 +1,121 @@
+#[allow(unused_extern_crates)]
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+
+use indexmap::{IndexMap, IndexSet};
+use proc_macro2::TokenStream as TokenStream2;
+use syn::Ident;
+
+use crate::syntax::ast::App;
+
+mod accessors;
+pub mod analyze;
+pub mod ast;
+mod check;
+mod parse;
+
+/// An ordered map keyed by identifier
+pub type Map<T> = IndexMap<Ident, T>;
+
+/// An order set
+pub type Set<T> = IndexSet<T>;
+
+/// Execution context
+#[derive(Clone, Copy)]
+pub enum Context<'a> {
+    /// The `idle` context
+    Idle,
+
+    /// The `init`-ialization function
+    Init,
+
+    /// A async software task
+    SoftwareTask(&'a Ident),
+
+    /// A hardware task
+    HardwareTask(&'a Ident),
+}
+
+impl<'a> Context<'a> {
+    /// The identifier of this context
+    pub fn ident(&self, app: &'a App) -> &'a Ident {
+        match self {
+            Context::HardwareTask(ident) => ident,
+            Context::Idle => &app.idle.as_ref().unwrap().name,
+            Context::Init => &app.init.name,
+            Context::SoftwareTask(ident) => ident,
+        }
+    }
+
+    /// Is this the `idle` context?
+    pub fn is_idle(&self) -> bool {
+        matches!(self, Context::Idle)
+    }
+
+    /// Is this the `init`-ialization context?
+    pub fn is_init(&self) -> bool {
+        matches!(self, Context::Init)
+    }
+
+    /// Whether this context runs only once
+    pub fn runs_once(&self) -> bool {
+        self.is_init() || self.is_idle()
+    }
+
+    /// Whether this context has shared resources
+    pub fn has_shared_resources(&self, app: &App) -> bool {
+        match *self {
+            Context::HardwareTask(name) => {
+                !app.hardware_tasks[name].args.shared_resources.is_empty()
+            }
+            Context::Idle => !app.idle.as_ref().unwrap().args.shared_resources.is_empty(),
+            Context::Init => false,
+            Context::SoftwareTask(name) => {
+                !app.software_tasks[name].args.shared_resources.is_empty()
+            }
+        }
+    }
+
+    /// Whether this context has local resources
+    pub fn has_local_resources(&self, app: &App) -> bool {
+        match *self {
+            Context::HardwareTask(name) => {
+                !app.hardware_tasks[name].args.local_resources.is_empty()
+            }
+            Context::Idle => !app.idle.as_ref().unwrap().args.local_resources.is_empty(),
+            Context::Init => !app.init.args.local_resources.is_empty(),
+            Context::SoftwareTask(name) => {
+                !app.software_tasks[name].args.local_resources.is_empty()
+            }
+        }
+    }
+}
+
+/// Parses the input of the `#[app]` attribute
+pub fn parse(
+    args: TokenStream,
+    input: TokenStream,
+) -> Result<(ast::App, analyze::Analysis), syn::parse::Error> {
+    parse2(args.into(), input.into())
+}
+
+/// `proc_macro2::TokenStream` version of `parse`
+pub fn parse2(
+    args: TokenStream2,
+    input: TokenStream2,
+) -> Result<(ast::App, analyze::Analysis), syn::parse::Error> {
+    let app = parse::app(args, input)?;
+    check::app(&app)?;
+
+    match analyze::app(&app) {
+        Err(e) => Err(e),
+        // If no errors, return the app and analysis results
+        Ok(analysis) => Ok((app, analysis)),
+    }
+}
+
+enum Either<A, B> {
+    Left(A),
+    Right(B),
+}