1 files changed, 59 insertions, 0 deletions
diff --git a/crypto/async/arch/async_win.c b/crypto/async/arch/async_win.c
new file mode 100644
index 000000000000..0b276fd504d8
--- /dev/null
+++ b/crypto/async/arch/async_win.c
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2015-2021 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+/* This must be the first #include file */
+#include "../async_local.h"
+
+#ifdef ASYNC_WIN
+
+# include <windows.h>
+# include "internal/cryptlib.h"
+
+int ASYNC_is_capable(void)
+{
+    return 1;
+}
+
+void async_local_cleanup(void)
+{
+    async_ctx *ctx = async_get_ctx();
+    if (ctx != NULL) {
+        async_fibre *fibre = &ctx->dispatcher;
+        if (fibre != NULL && fibre->fibre != NULL && fibre->converted) {
+            ConvertFiberToThread();
+            fibre->fibre = NULL;
+        }
+    }
+}
+
+int async_fibre_init_dispatcher(async_fibre *fibre)
+{
+# if defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x600
+    fibre->fibre = ConvertThreadToFiberEx(NULL, FIBER_FLAG_FLOAT_SWITCH);
+# else
+    fibre->fibre = ConvertThreadToFiber(NULL);
+# endif
+    if (fibre->fibre == NULL) {
+        fibre->converted = 0;
+        fibre->fibre = GetCurrentFiber();
+        if (fibre->fibre == NULL)
+            return 0;
+    } else {
+        fibre->converted = 1;
+    }
+
+    return 1;
+}
+
+VOID CALLBACK async_start_func_win(PVOID unused)
+{
+    async_start_func();
+}
+
+#endif