sys crate (#583)

Fix #508.

bdwgc-alloc-sys/tests/collector.rs

@@ -0,0 +1,76 @@
+//! A smoke test of the bindings.
+
+use bdwgc_alloc_sys::{
+    GC_SUCCESS, GC_allow_register_threads, GC_free, GC_gcollect, GC_get_stack_base, GC_init,
+    GC_malloc, GC_realloc, GC_register_finalizer, GC_register_my_thread, GC_stack_base,
+    GC_unregister_my_thread,
+};
+use core::{
+    ffi::c_void,
+    ptr::null_mut,
+    sync::atomic::{AtomicUsize, Ordering},
+};
+use std::thread::spawn;
+
+const TOTAL_COUNT: usize = 1 << 10;
+
+static FINALIZED_COUNT: AtomicUsize = AtomicUsize::new(0);
+
+fn main() {
+    unsafe {
+        GC_init();
+        GC_allow_register_threads();
+    }
+
+    allocate();
+    finalize();
+    register_thread();
+}
+
+fn allocate() {
+    let ptr = unsafe { GC_malloc(42) };
+    assert!(!ptr.is_null());
+
+    let ptr = unsafe { GC_realloc(ptr, 84) };
+    assert!(!ptr.is_null());
+
+    unsafe { GC_free(ptr) };
+}
+
+fn finalize() {
+    extern "C" fn count(_object: *mut c_void, _client_data: *mut c_void) {
+        FINALIZED_COUNT.fetch_add(1, Ordering::Relaxed);
+    }
+
+    for _ in 0..TOTAL_COUNT {
+        unsafe {
+            GC_register_finalizer(
+                GC_malloc(42),
+                Some(count),
+                null_mut(),
+                null_mut(),
+                null_mut(),
+            );
+        }
+    }
+
+    unsafe { GC_gcollect() };
+
+    // TODO Is there any way to collect all?
+    assert!(FINALIZED_COUNT.load(Ordering::Relaxed) > TOTAL_COUNT / 2);
+}
+
+fn register_thread() {
+    spawn(|| {
+        let mut base = GC_stack_base {
+            mem_base: null_mut(),
+        };
+
+        assert_eq!(unsafe { GC_get_stack_base(&mut base) }, GC_SUCCESS);
+        assert_eq!(unsafe { GC_register_my_thread(&base) }, GC_SUCCESS);
+        assert!(!unsafe { GC_malloc(42) }.is_null());
+        assert_eq!(unsafe { GC_unregister_my_thread() }, GC_SUCCESS);
+    })
+    .join()
+    .unwrap();
+}