From 2efb46afd519fb5595a36b4244d592acd61873cc Mon Sep 17 00:00:00 2001
From: Nick Fitzgerald <fitzgen@gmail.com>
Date: Tue, 21 Jul 2020 09:33:34 -0700
Subject: [PATCH] wasmtime-c-api: Add `wasmtime_store_gc` for GCing
 `externref`s

---
 crates/c-api/include/wasmtime.h | 11 +++++++++++
 crates/c-api/src/store.rs       |  5 +++++
 2 files changed, 16 insertions(+)

diff --git a/crates/c-api/include/wasmtime.h b/crates/c-api/include/wasmtime.h
index 972dfb2f8e..ee2c2fc002 100644
--- a/crates/c-api/include/wasmtime.h
+++ b/crates/c-api/include/wasmtime.h
@@ -299,6 +299,17 @@ WASM_API_EXTERN own wasmtime_error_t* wasmtime_wat2wasm(
     own wasm_byte_vec_t *ret
 );
 
+/**
+ * \brief Perform garbage collection within the given store.
+ *
+ * Garbage collects `externref`s that are used within this store. Any
+ * `externref`s that are discovered to be unreachable by other code or objects
+ * will have their finalizers run.
+ *
+ * The `store` argument must not be NULL.
+ */
+WASM_API_EXTERN void wasmtime_store_gc(wasm_store_t* store);
+
 /**
  * \typedef wasmtime_linker_t
  * \brief Convenience alias for #wasmtime_linker_t
diff --git a/crates/c-api/src/store.rs b/crates/c-api/src/store.rs
index 625b3831ea..018f06729c 100644
--- a/crates/c-api/src/store.rs
+++ b/crates/c-api/src/store.rs
@@ -17,6 +17,11 @@ pub extern "C" fn wasm_store_new(engine: &wasm_engine_t) -> Box<wasm_store_t> {
     })
 }
 
+#[no_mangle]
+pub extern "C" fn wasmtime_store_gc(store: &wasm_store_t) {
+    store.store.gc();
+}
+
 #[repr(C)]
 pub struct wasmtime_interrupt_handle_t {
     handle: InterruptHandle,