fs: implement AccessLog, enable for File operations

libraries/libstratosphere/include/stratosphere/fs/fs_context.hpp

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2018-2020 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 <vapours.hpp>
+
+namespace ams::fs {
+
+    enum class AbortSpecifier {
+        Default,
+        Abort,
+        Return,
+    };
+
+    using ResultHandler = AbortSpecifier (*)(Result);
+
+    class FsContext {
+        private:
+            ResultHandler handler;
+        public:
+            constexpr explicit FsContext(ResultHandler h) : handler(h) { /* ... */ }
+
+            constexpr void SetHandler(ResultHandler h) { this->handler = h; }
+
+            constexpr AbortSpecifier HandleResult(Result result) const { return this->handler(result); }
+    };
+
+    void SetDefaultFsContextResultHandler(const ResultHandler handler);
+
+    const FsContext *GetCurrentThreadFsContext();
+    void SetCurrentThreadFsContext(const FsContext *context);
+
+    class ScopedFsContext {
+        private:
+            const FsContext * const prev_context;
+        public:
+            ALWAYS_INLINE ScopedFsContext(const FsContext &ctx) : prev_context(GetCurrentThreadFsContext()) {
+                SetCurrentThreadFsContext(std::addressof(ctx));
+            }
+
+            ALWAYS_INLINE ~ScopedFsContext() {
+                SetCurrentThreadFsContext(this->prev_context);
+            }
+    };
+
+    class ScopedAutoAbortDisabler {
+        private:
+            const FsContext * const prev_context;
+        public:
+            ScopedAutoAbortDisabler();
+            ALWAYS_INLINE ~ScopedAutoAbortDisabler() {
+                SetCurrentThreadFsContext(this->prev_context);
+            }
+    };
+
+}