Add a `State` struct

The plan is to use this as an opaque pointer to be passed between the
Objective-C code and Rust code. It will contain the current mode (if in
a mode) and the parsed `MapGroup` definitions.

For now just some code inspired by the Rust FFI Omnibus
(http://jakegoulding.com/rust-ffi-omnibus/objects/) to create and free a
`State`.

1 files changed, 6 insertions, 0 deletions

diff --git a/dome_key_map.h b/dome_key_map.h
index 7bd77ca..633e9b3 100644
--- a/dome_key_map.h
+++ b/dome_key_map.h
@@ -23,6 +23,8 @@ typedef enum {
   MapKind_Command,
 } MapKind;
 
+typedef struct State State;
+
 typedef struct {
   const HeadphoneButton *buttons;
   size_t length;
@@ -35,3 +37,7 @@ typedef struct {
 } CKeyActionResult;
 
 const CKeyActionResult *c_run_key_action(Trigger trigger, const Trigger *mode);
+
+void state_free(State *ptr);
+
+State *state_new(void);