erpt: reimplement the sysmodule (#875)

* erpt: reimplement the sysmodule

* fatal: update for latest bindings

* erpt: amend logic for culling orphan attachments

libraries/libstratosphere/source/erpt/srv/erpt_srv_attachment.hpp

@@ -0,0 +1,62 @@
+/*
+ * 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 <stratosphere.hpp>
+#include "erpt_srv_allocator.hpp"
+#include "erpt_srv_stream.hpp"
+#include "erpt_srv_journal.hpp"
+
+namespace ams::erpt::srv {
+
+    enum AttachmentOpenType {
+        AttachmentOpenType_Create = 0,
+        AttachmentOpenType_Read   = 1,
+    };
+
+    constexpr inline u32 AttachmentStreamBufferSize = 1_KB;
+
+    class Attachment : public Allocator, public Stream {
+        private:
+            JournalRecord<AttachmentInfo> *record;
+        private:
+            AttachmentFileName FileName();
+        public:
+            static AttachmentFileName FileName(AttachmentId attachment_id);
+        public:
+            explicit Attachment(JournalRecord<AttachmentInfo> *r);
+            ~Attachment();
+
+            Result Open(AttachmentOpenType type);
+            Result Read(u32 *out_read_count, u8 *dst, u32 dst_size);
+            Result Delete();
+            void Close();
+
+            Result GetFlags(AttachmentFlagSet *out);
+            Result SetFlags(AttachmentFlagSet flags);
+            Result GetSize(s64 *out);
+
+            template<typename T>
+            Result Write(T val) {
+                return this->WriteStream(reinterpret_cast<const u8 *>(std::addressof(val)), sizeof(val));
+            }
+
+            template<typename T>
+            Result Write(const T *buf, u32 buffer_size) {
+                return this->WriteStream(reinterpret_cast<const u8 *>(buf), buffer_size);
+            }
+    };
+
+}