From e50296ceab22d49463b7bbe7174a98532afba9f5 Mon Sep 17 00:00:00 2001
From: Balazs Racz <balazs.racz@gmail.com>
Date: Mon, 6 Jun 2022 16:30:14 +0200
Subject: [PATCH] Adds implementation of factory_reset command.  (#624)

* Adds implementation of factory_reset command.

Adds unit test for factory reset and reboot commands.

* Adds a reboot after the factory reset is complete and quiesced.

* Removes wrong comment.
---
 src/openlcb/MemoryConfig.cxx     | 17 +++++++++
 src/openlcb/MemoryConfig.cxxtest | 59 +++++++++++++++++++++++++++++++-
 src/openlcb/MemoryConfig.hxx     | 25 ++++++++++++++
 3 files changed, 100 insertions(+), 1 deletion(-)

diff --git a/src/openlcb/MemoryConfig.cxx b/src/openlcb/MemoryConfig.cxx
index fd543f154..f6d6ee215 100644
--- a/src/openlcb/MemoryConfig.cxx
+++ b/src/openlcb/MemoryConfig.cxx
@@ -44,6 +44,8 @@
 #include "can_ioctl.h"
 #endif
 
+#include "openlcb/ConfigUpdateFlow.hxx"
+
 extern "C" {
 /// Implement this function (usually in HwInit.cxx) to enter the
 /// bootloader. Usual implementations write some magic value to RAM and the
@@ -65,6 +67,21 @@ void reboot()
 namespace openlcb
 {
 
+#ifdef GTEST
+static constexpr unsigned FACTORY_RESET_REBOOT_DELAY_MSEC = 50;
+#else
+static constexpr unsigned FACTORY_RESET_REBOOT_DELAY_MSEC = 500;
+#endif
+
+
+void __attribute__((weak)) MemoryConfigHandler::handle_factory_reset()
+{
+    static_cast<ConfigUpdateFlow *>(ConfigUpdateFlow::instance())
+        ->factory_reset();
+    (new RebootTimer(service()))
+        ->start(MSEC_TO_NSEC(FACTORY_RESET_REBOOT_DELAY_MSEC));
+}
+
 FileMemorySpace::FileMemorySpace(int fd, address_t len)
     : fileSize_(len)
     , name_(nullptr)
diff --git a/src/openlcb/MemoryConfig.cxxtest b/src/openlcb/MemoryConfig.cxxtest
index 88dba9471..839a3115c 100644
--- a/src/openlcb/MemoryConfig.cxxtest
+++ b/src/openlcb/MemoryConfig.cxxtest
@@ -32,9 +32,12 @@
  * @date 23 Feb 2014
  */
 
-#include "utils/async_datagram_test_helper.hxx"
 #include "openlcb/MemoryConfig.hxx"
 
+#include "utils/async_datagram_test_helper.hxx"
+#include "utils/ConfigUpdateListener.hxx"
+#include "openlcb/ConfigUpdateFlow.hxx"
+
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -372,6 +375,60 @@ TEST_F(MemoryConfigTest, GetSpaceInfoRO_NZLA)
     wait();
 }
 
+struct GlobalMock : public Singleton<GlobalMock> {
+    MOCK_METHOD0(reboot, void());
+    MOCK_METHOD0(factory_reset, void());
+};
+
+extern "C" void reboot()
+{
+    GlobalMock::instance()->reboot();
+}
+
+struct FactoryResetListener : public DefaultConfigUpdateListener
+{
+    void factory_reset(int fd) override
+    {
+        GlobalMock::instance()->factory_reset();
+    }
+
+    UpdateAction apply_configuration(
+        int fd, bool initial_load, BarrierNotifiable *done)
+    {
+        done->notify();
+        return UPDATED;
+    }
+};
+
+TEST_F(MemoryConfigTest, Reboot)
+{
+    StrictMock<GlobalMock> mock;
+    // Normally, a reboot function never returns. We can't do that under linux
+    // though, so the stack will generate an error datagram reply.
+    expect_packet(":X19A4822AN077C1041;"); // unsupported command
+
+    EXPECT_CALL(mock, reboot());
+    send_packet(":X1A22A77CN20A9;");
+    wait();
+}
+
+TEST_F(MemoryConfigTest, FactoryReset)
+{
+    StrictMock<GlobalMock> mock;
+    ConfigUpdateFlow update_flow{ifCan_.get()};
+    update_flow.TEST_set_fd(23);
+    
+    FactoryResetListener l;
+    expect_packet(":X19A2822AN077C00;"); // received OK, no response
+
+    EXPECT_CALL(mock, factory_reset());
+    send_packet(":X1A22A77CN20AA;");
+    wait();
+
+    EXPECT_CALL(mock, reboot());
+    twait();
+}
+
 static const char MEMORY_BLOCK_DATA[] = "abrakadabra12345678xxxxyyyyzzzzwww.";
 
 class StaticBlockTest : public MemoryConfigTest
diff --git a/src/openlcb/MemoryConfig.hxx b/src/openlcb/MemoryConfig.hxx
index 04dd3cffc..218a7b151 100644
--- a/src/openlcb/MemoryConfig.hxx
+++ b/src/openlcb/MemoryConfig.hxx
@@ -482,6 +482,11 @@ private:
 #endif
                 return respond_reject(Defs::ERROR_UNIMPLEMENTED_SUBCMD);
             }
+            case MemoryConfigDefs::COMMAND_FACTORY_RESET:
+            {
+                handle_factory_reset();
+                return respond_ok(0);
+            }
             case MemoryConfigDefs::COMMAND_OPTIONS:
             {
                 return call_immediately(STATE(handle_options));
@@ -513,6 +518,26 @@ private:
         }
     }
 
+    /// Used internally by the factory_reset implementation to reboot the
+    /// binary asynchronously.
+    class RebootTimer : public ::Timer
+    {
+    public:
+        RebootTimer(Service *s)
+            : ::Timer(s->executor()->active_timers())
+        { }
+
+        long long timeout() override
+        {
+            reboot();
+            return DELETE;
+        }
+    };
+
+    /// Invokes the openlcb config handler to do a factory reset. Starts a
+    /// timer to reboot the device after a little time.
+    void handle_factory_reset();
+    
     Action ok_response_sent() OVERRIDE
     {
         if (!response_.empty())