Configure for importing from C/FFI

* Add `#[repr(C)]` on `HeadphoneButton` to hopefully be able to use it
  outside Rust
* Add `#[no_mangle]` to `run_key_action()`
* Export `run_key_action()` as a public function
* Build the crate as a static library

(But holy cow, a 19 MB library file?)

4 files changed, 7 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 851ed38..23af201 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,3 +5,6 @@ version = "0.0.1"
 [dependencies]
 cocoa = "0.18.0"
 combine = "3.4.0"
+
+[lib]
+crate-type = ["staticlib"]
diff --git a/src/cocoa_bridge.rs b/src/cocoa_bridge.rs
index df144f1..d4749f0 100644
--- a/src/cocoa_bridge.rs
+++ b/src/cocoa_bridge.rs
@@ -44,6 +44,7 @@ pub struct KeyActionResult {
     pub kind: MapKind,
 }
 
+#[no_mangle]
 pub extern "C" fn run_key_action(
     trigger: &[HeadphoneButton]
 ) -> Option<KeyActionResult> {
diff --git a/src/lib.rs b/src/lib.rs
index 7fb0b92..3127631 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -7,3 +7,5 @@ mod cocoa_bridge;
 mod parser;
 
 use parser::{HeadphoneButton, MapGroup, MapKind};
+
+pub use cocoa_bridge::run_key_action;
diff --git a/src/parser.rs b/src/parser.rs
index d5cd860..c6c8cce 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -13,6 +13,7 @@ use combine::parser::char::{
 use combine::parser::repeat::take_until;
 use combine::stream::state::{SourcePosition, State};
 
+#[repr(C)]
 #[derive(Debug, Hash, Eq, PartialEq)]
 pub enum HeadphoneButton {
     Play,