[tma2] [Ongoing] Continue implementing modules for tma2. (#1388)

* cs: add stub sysmodule to host command shell server

* cs: implement logic for main (linker error paradise, for now)

* cs: implement more of the system module's skeleton

* htcs: update client type names for libnx pr merge

libraries/libstratosphere/source/scs/scs_command_processor.cpp

@@ -0,0 +1,99 @@
+/*
+ * 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/>.
+ */
+#include <stratosphere.hpp>
+
+namespace ams::scs {
+
+    namespace {
+
+        struct ResponseError {
+            ResponseHeader header;
+            u32 result;
+        };
+
+        constinit os::SdkMutex g_htcs_send_mutex;
+
+    }
+
+    os::SdkMutex &GetHtcsSendMutex() {
+        return g_htcs_send_mutex;
+    }
+
+    void CommandProcessor::SendSuccess(s32 socket, const CommandHeader &header) {
+        /* Build the response. */
+        const ResponseHeader response = {
+            .id        = header.id,
+            .response  = Response_Success,
+            .body_size = 0,
+        };
+
+        /* Send the response. */
+        std::scoped_lock lk(GetHtcsSendMutex());
+        htcs::Send(socket, std::addressof(response), sizeof(response), 0);
+    }
+
+    void CommandProcessor::SendErrorResult(s32 socket, const CommandHeader &header, Result result) {
+        return SendErrorResult(socket, header.id, result);
+    }
+
+    void CommandProcessor::SendErrorResult(s32 socket, u64 id, Result result) {
+        /* Build the response. */
+        const ResponseError response = {
+            .header = {
+                .id        = id,
+                .response  = Response_Error,
+                .body_size = sizeof(response) - sizeof(response.header),
+            },
+            .result = result.GetValue(),
+        };
+
+        /* Send the response. */
+        std::scoped_lock lk(GetHtcsSendMutex());
+        htcs::Send(socket, std::addressof(response), sizeof(response), 0);
+    }
+
+    void CommandProcessor::OnProcessStart(u64 id, s32 socket, os::ProcessId process_id) {
+        /* TODO */
+        AMS_ABORT("CommandProcessor::OnProcessStart");
+    }
+
+    void CommandProcessor::OnProcessExit(u64 id, s32 socket, os::ProcessId process_id) {
+        /* TODO */
+        AMS_ABORT("CommandProcessor::OnProcessExit");
+    }
+
+    void CommandProcessor::OnProcessJitDebug(u64 id, s32 socket, os::ProcessId process_id) {
+        /* TODO */
+        AMS_ABORT("CommandProcessor::OnProcessJitDebug");
+    }
+
+    void CommandProcessor::Initialize() {
+        /* Register our process event handlers. */
+        scs::RegisterCommonProcessEventHandler(OnProcessStart, OnProcessExit, OnProcessJitDebug);
+    }
+
+    bool CommandProcessor::ProcessCommand(const CommandHeader &header, const u8 *body, s32 socket) {
+        switch (header.command) {
+            /* TODO: Support commands. */
+            default:
+                SendErrorResult(socket, header, scs::ResultUnknownCommand());
+                break;
+        }
+
+        return true;
+    }
+
+}