ams: support building unit test programs on windows/linux/macos

libraries/libstratosphere/source/fssrv/fssrv_retry_utility.hpp

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+#include <stratosphere.hpp>
+
+namespace ams::fssrv::impl {
+
+    template<typename F>
+    ALWAYS_INLINE Result RetryFinitelyForDataCorrupted(F f) {
+        /* All official uses of this retry once, for two tries total. */
+        constexpr auto MaxTryCount = 2;
+
+        /* Perform the operation, retrying on fs::ResultDataCorrupted. */
+        auto tries = 0;
+        while (true) {
+            /* Try to perform the operation. */
+            const auto rc = f();
+
+            /* If we should, retry. */
+            if (fs::ResultDataCorrupted::Includes(rc)) {
+                if ((++tries) < MaxTryCount) {
+                    continue;
+                }
+            }
+
+            /* Ensure the current attempt succeeded. */
+            R_TRY(rc);
+
+            /* Return success. */
+            R_SUCCEED();
+        }
+    }
+
+}