Plumbing for promise integration.

clients/c/promise.h

@@ -0,0 +1,19 @@
+#ifndef _PROMISE_H
+#define _PROMISE_H
+
+#include <stdbool.h>
+
+typedef struct promise promise;
+
+// (passthrough, result)
+typedef void (*promise_callback)(void *, void *);
+
+promise *promise_create(bool will_wait, promise_callback on_success, promise_callback on_failure, void *passthrough);
+bool promise_wait(promise *promise_obj, void **result);
+
+void promise_complete(promise *promise_obj, void *result, bool success);
+// Shortcuts for promise_complete()
+void promise_succeed(promise *promise_obj, void *result);
+void promise_fail(promise *promise_obj, void *result);
+
+#endif