1 files changed, 34 insertions, 0 deletions
diff --git a/libgo/runtime/go-closed.c b/libgo/runtime/go-closed.c
new file mode 100644
index 000000000..bfa9cd6f9
--- /dev/null
+++ b/libgo/runtime/go-closed.c
@@ -0,0 +1,34 @@
+/* go-closed.c -- the builtin closed function.
+
+   Copyright 2009 The Go Authors. All rights reserved.
+   Use of this source code is governed by a BSD-style
+   license that can be found in the LICENSE file.  */
+
+#include "go-assert.h"
+#include "channel.h"
+
+/* Return whether a channel is closed.  We only return true after at
+   least one nil value has been read from the channel.  */
+
+_Bool
+__go_builtin_closed (struct __go_channel *channel)
+{
+  int i;
+  _Bool ret;
+
+  i = pthread_mutex_lock (&channel->lock);
+  __go_assert (i == 0);
+
+  while (channel->selected_for_receive)
+    {
+      i = pthread_cond_wait (&channel->cond, &channel->lock);
+      __go_assert (i == 0);
+    }
+
+  ret = channel->saw_close;
+
+  i = pthread_mutex_unlock (&channel->lock);
+  __go_assert (i == 0);
+
+  return ret;
+}