Add MemoryVerifier to AchievementManager Startup

rc_client calls the provided memory peeker asynchronously in the callback for starting a session, to validate/invalidate the memory used for achievements. Dolphin cannot access memory from any thread but host or CPU so this access has a small chance of being invalid. This commit adds a MemoryVerifier that the AchievementManager will use to perform this, before changing the peek method back to the original MemoryPeeker for normal operation.

Source/Core/Core/AchievementManager.cpp

@@ -44,7 +44,7 @@ void AchievementManager::Init()
   LoadDefaultBadges();
   if (!m_client && Config::Get(Config::RA_ENABLED))
   {
-    m_client = rc_client_create(MemoryPeeker, Request);
+    m_client = rc_client_create(MemoryVerifier, Request);
     std::string host_url = Config::Get(Config::RA_HOST_URL);
     if (!host_url.empty())
       rc_client_set_host(m_client, host_url.c_str());
@@ -679,12 +679,14 @@ void AchievementManager::LoadGameCallback(int result, const char* error_message,
   }
   INFO_LOG_FMT(ACHIEVEMENTS, "Loaded data for game ID {}.", game->id);
 
-  AchievementManager::GetInstance().m_display_welcome_message = true;
-  AchievementManager::GetInstance().FetchGameBadges();
-  AchievementManager::GetInstance().m_system = &Core::System::GetInstance();
-  AchievementManager::GetInstance().m_update_callback({.all = true});
+  auto& instance = AchievementManager::GetInstance();
+  rc_client_set_read_memory_function(instance.m_client, MemoryPeeker);
+  instance.m_display_welcome_message = true;
+  instance.FetchGameBadges();
+  instance.m_system = &Core::System::GetInstance();
+  instance.m_update_callback({.all = true});
   // Set this to a value that will immediately trigger RP
-  AchievementManager::GetInstance().m_last_rp_time =
+  instance.m_last_rp_time =
       std::chrono::steady_clock::now() - std::chrono::minutes{2};
 }
 
@@ -914,6 +916,13 @@ void AchievementManager::Request(const rc_api_request_t* request,
       });
 }
 
+u32 AchievementManager::MemoryVerifier(u32 address, u8* buffer, u32 num_bytes, rc_client_t* client)
+{
+  for (u32 ix = 0; ix < num_bytes; ix++)
+    buffer[ix] = 0xcd;
+  return std::min(0x17fffff - address, num_bytes);
+}
+
 u32 AchievementManager::MemoryPeeker(u32 address, u8* buffer, u32 num_bytes, rc_client_t* client)
 {
   if (buffer == nullptr)

Source/Core/Core/AchievementManager.h

@@ -177,6 +177,7 @@ class AchievementManager
 
   static void Request(const rc_api_request_t* request, rc_client_server_callback_t callback,
                       void* callback_data, rc_client_t* client);
+  static u32 MemoryVerifier(u32 address, u8* buffer, u32 num_bytes, rc_client_t* client);
   static u32 MemoryPeeker(u32 address, u8* buffer, u32 num_bytes, rc_client_t* client);
   void FetchBadge(Badge* badge, u32 badge_type, const BadgeNameFunction function,
                   const UpdatedItems callback_data);