From 18d1c3e6d14e93f78ab6d39bcfbe16d8043f2cd1 Mon Sep 17 00:00:00 2001
From: Bradlee Speice <bradlee@speice.io>
Date: Tue, 6 Nov 2018 23:04:26 -0500
Subject: [PATCH] Start work on a procedural macro Turns out the system still
 needs some work.

---
 Cargo.toml                          |  4 +++-
 qadapt-macro/.gitignore             |  3 +++
 qadapt-macro/Cargo.toml             |  9 +++++++++
 qadapt-macro/src/lib.rs             | 31 +++++++++++++++++++++++++++++
 src/lib.rs                          |  4 ++++
 tests/{simple.rs => allocations.rs} |  1 -
 6 files changed, 50 insertions(+), 2 deletions(-)
 create mode 100644 qadapt-macro/.gitignore
 create mode 100644 qadapt-macro/Cargo.toml
 create mode 100644 qadapt-macro/src/lib.rs
 rename tests/{simple.rs => allocations.rs} (99%)

diff --git a/Cargo.toml b/Cargo.toml
index 68ce1f5..8b19f40 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,4 +12,6 @@ repository = "https://github.com/bspeice/qadapt.git"
 backtrace = "0.3"
 libc = "0.2"
 log = "0.4"
-spin = "0.4"
\ No newline at end of file
+spin = "0.4"
+
+qadapt-macro = { path = "./qadapt-macro" }
\ No newline at end of file
diff --git a/qadapt-macro/.gitignore b/qadapt-macro/.gitignore
new file mode 100644
index 0000000..6936990
--- /dev/null
+++ b/qadapt-macro/.gitignore
@@ -0,0 +1,3 @@
+/target
+**/*.rs.bk
+Cargo.lock
diff --git a/qadapt-macro/Cargo.toml b/qadapt-macro/Cargo.toml
new file mode 100644
index 0000000..0342b5a
--- /dev/null
+++ b/qadapt-macro/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "qadapt-macro"
+version = "0.1.0"
+authors = ["Bradlee Speice <bradlee@speice.io>"]
+
+[lib]
+proc-macro = true
+
+[dependencies]
diff --git a/qadapt-macro/src/lib.rs b/qadapt-macro/src/lib.rs
new file mode 100644
index 0000000..47512b4
--- /dev/null
+++ b/qadapt-macro/src/lib.rs
@@ -0,0 +1,31 @@
+//! Helper macros to use with the QADAPT allocator system
+//! 
+//! This crate is unusable on its own, but because `proc_macro` crates
+//! can't export non-proc-macro symbols, we have to go through an extra step
+//! to move these up.
+//! 
+//! Ultimately, this does actually work because we don't need to actually use
+//! references to the underlying functionality here, we just need to know
+//! where they will ultimately end up at.
+// TODO: This causes issues, but I can't track down why
+// #![deny(missing_docs)]
+extern crate proc_macro;
+
+use proc_macro::TokenTree;
+use proc_macro::TokenStream;
+
+/// Set up the QADAPT allocator to trigger a panic if any allocations happen during
+/// this function. Race conditions between threads are not checked, this macro will
+/// only work as intended in a single-threaded or otherwise synchronized environment.
+#[proc_macro_attribute]
+pub fn allocate_panic(_attr: TokenStream, item: TokenStream) -> TokenStream {
+    let ret = item.clone();
+
+    let mut token_iter = item.into_iter();
+    match token_iter.next() {
+        Some(TokenTree::Ident(ref i)) if i.to_string() == "fn" => (),
+        _ => panic!("#[allocate_panic] macro can only be applied to functions")
+    }
+
+    ret
+}
diff --git a/src/lib.rs b/src/lib.rs
index b8251f8..ccfdfd4 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,9 +1,13 @@
 extern crate backtrace;
 extern crate libc;
+extern crate qadapt_macro;
 #[macro_use]
 extern crate log;
 extern crate spin;
 
+// Re-export the proc macros to use by other code
+pub use qadapt_macro::*;
+
 use backtrace::Backtrace;
 use libc::c_void;
 use libc::free;
diff --git a/tests/simple.rs b/tests/allocations.rs
similarity index 99%
rename from tests/simple.rs
rename to tests/allocations.rs
index bc09bb1..327444d 100644
--- a/tests/simple.rs
+++ b/tests/allocations.rs
@@ -1,5 +1,4 @@
 #![feature(asm)]
-
 extern crate qadapt;
 
 use qadapt::QADAPT;