NetPlay save data synchronization

This adds the functionality of sending the host's save data (raw memory
cards, as well as GCI files and Wii saves with a matching GameID) to
all other clients. The data is compressed using LZO1X to greatly reduce
its size while keeping compression/decompression fast. Save
synchronization is enabled by default, and toggleable with a checkbox
in the NetPlay dialog.

On clicking start, if the option is enabled, game boot will be delayed
until all players have received the save data sent by the host. If any
player fails to receive it properly, boot will be cancelled to prevent
desyncs.

1 files changed, 51 insertions, 15 deletions

diff --git a/Source/Core/DolphinQt/NetPlay/NetPlayDialog.cpp b/Source/Core/DolphinQt/NetPlay/NetPlayDialog.cpp
index d4cfacb605..ce296acef8 100644
--- a/Source/Core/DolphinQt/NetPlay/NetPlayDialog.cpp
+++ b/Source/Core/DolphinQt/NetPlay/NetPlayDialog.cpp
@@ -86,6 +86,7 @@ void NetPlayDialog::CreateMainLayout()
   m_buffer_size_box = new QSpinBox;
   m_save_sd_box = new QCheckBox(tr("Write save/SD data"));
   m_load_wii_box = new QCheckBox(tr("Load Wii Save"));
+  m_sync_save_data_box = new QCheckBox(tr("Sync Saves"));
   m_record_input_box = new QCheckBox(tr("Record inputs"));
   m_reduce_polling_rate_box = new QCheckBox(tr("Reduce Polling Rate"));
   m_buffer_label = new QLabel(tr("Buffer:"));
@@ -95,6 +96,8 @@ void NetPlayDialog::CreateMainLayout()
   m_game_button->setDefault(false);
   m_game_button->setAutoDefault(false);
 
+  m_sync_save_data_box->setChecked(true);
+
   auto* default_button = new QAction(tr("Calculate MD5 hash"), m_md5_button);
 
   auto* menu = new QMenu(this);
@@ -140,6 +143,7 @@ void NetPlayDialog::CreateMainLayout()
   options_widget->addWidget(m_buffer_size_box);
   options_widget->addWidget(m_save_sd_box);
   options_widget->addWidget(m_load_wii_box);
+  options_widget->addWidget(m_sync_save_data_box);
   options_widget->addWidget(m_record_input_box);
   options_widget->addWidget(m_reduce_polling_rate_box);
   options_widget->addWidget(m_quit_button);
@@ -305,9 +309,11 @@ void NetPlayDialog::OnStart()
   settings.m_ReducePollingRate = m_reduce_polling_rate_box->isChecked();
   settings.m_EXIDevice[0] = instance.m_EXIDevice[0];
   settings.m_EXIDevice[1] = instance.m_EXIDevice[1];
+  settings.m_SyncSaveData = m_sync_save_data_box->isChecked();
 
   Settings::Instance().GetNetPlayServer()->SetNetSettings(settings);
-  Settings::Instance().GetNetPlayServer()->StartGame();
+  if (Settings::Instance().GetNetPlayServer()->RequestStartGame())
+    SetOptionsEnabled(false);
 }
 
 void NetPlayDialog::reject()
@@ -346,6 +352,7 @@ void NetPlayDialog::show(std::string nickname, bool use_traversal)
   m_start_button->setHidden(!is_hosting);
   m_save_sd_box->setHidden(!is_hosting);
   m_load_wii_box->setHidden(!is_hosting);
+  m_sync_save_data_box->setHidden(!is_hosting);
   m_reduce_polling_rate_box->setHidden(!is_hosting);
   m_buffer_size_box->setHidden(!is_hosting);
   m_buffer_label->setHidden(!is_hosting);
@@ -374,7 +381,6 @@ void NetPlayDialog::UpdateGUI()
 
   m_player_count = static_cast<int>(players.size());
 
-
   int selection_pid = m_players_list->currentItem() ?
                           m_players_list->currentItem()->data(Qt::UserRole).toInt() :
                           -1;
@@ -487,6 +493,11 @@ void NetPlayDialog::StopGame()
   emit Stop();
 }
 
+bool NetPlayDialog::IsHosting() const
+{
+  return Settings::Instance().GetNetPlayServer() != nullptr;
+}
+
 void NetPlayDialog::Update()
 {
   QueueOnObject(this, &NetPlayDialog::UpdateGUI);
@@ -539,19 +550,23 @@ void NetPlayDialog::GameStatusChanged(bool running)
   if (!running && !m_got_stop_request)
     Settings::Instance().GetNetPlayClient()->RequestStopGame();
 
-  QueueOnObject(this, [this, running] {
-    if (Settings::Instance().GetNetPlayServer() != nullptr)
-    {
-      m_start_button->setEnabled(!running);
-      m_game_button->setEnabled(!running);
-      m_load_wii_box->setEnabled(!running);
-      m_save_sd_box->setEnabled(!running);
-      m_assign_ports_button->setEnabled(!running);
-      m_reduce_polling_rate_box->setEnabled(!running);
-    }
+  QueueOnObject(this, [this, running] { SetOptionsEnabled(!running); });
+}
 
-    m_record_input_box->setEnabled(!running);
-  });
+void NetPlayDialog::SetOptionsEnabled(bool enabled)
+{
+  if (Settings::Instance().GetNetPlayServer() != nullptr)
+  {
+    m_start_button->setEnabled(enabled);
+    m_game_button->setEnabled(enabled);
+    m_load_wii_box->setEnabled(enabled);
+    m_save_sd_box->setEnabled(enabled);
+    m_sync_save_data_box->setEnabled(enabled);
+    m_assign_ports_button->setEnabled(enabled);
+    m_reduce_polling_rate_box->setEnabled(enabled);
+  }
+
+  m_record_input_box->setEnabled(enabled);
 }
 
 void NetPlayDialog::OnMsgStartGame()
@@ -618,6 +633,11 @@ void NetPlayDialog::OnTraversalError(TraversalClient::FailureReason error)
   });
 }
 
+void NetPlayDialog::OnSaveDataSyncFailure()
+{
+  QueueOnObject(this, [this] { SetOptionsEnabled(true); });
+}
+
 bool NetPlayDialog::IsRecording()
 {
   std::optional<bool> is_recording = RunOnObject(m_record_input_box, &QCheckBox::isChecked);
@@ -628,7 +648,7 @@ bool NetPlayDialog::IsRecording()
 
 std::string NetPlayDialog::FindGame(const std::string& game)
 {
-  std::optional<std::string> path = RunOnObject(this, [this, game] {
+  std::optional<std::string> path = RunOnObject(this, [this, &game] {
     for (int i = 0; i < m_game_list_model->rowCount(QModelIndex()); i++)
     {
       if (m_game_list_model->GetUniqueIdentifier(i).toStdString() == game)
@@ -641,6 +661,22 @@ std::string NetPlayDialog::FindGame(const std::string& game)
   return std::string("");
 }
 
+std::shared_ptr<const UICommon::GameFile> NetPlayDialog::FindGameFile(const std::string& game)
+{
+  std::optional<std::shared_ptr<const UICommon::GameFile>> game_file =
+      RunOnObject(this, [this, &game] {
+        for (int i = 0; i < m_game_list_model->rowCount(QModelIndex()); i++)
+        {
+          if (m_game_list_model->GetUniqueIdentifier(i).toStdString() == game)
+            return m_game_list_model->GetGameFile(i);
+        }
+        return static_cast<std::shared_ptr<const UICommon::GameFile>>(nullptr);
+      });
+  if (game_file)
+    return *game_file;
+  return nullptr;
+}
+
 void NetPlayDialog::ShowMD5Dialog(const std::string& file_identifier)
 {
   QueueOnObject(this, [this, file_identifier] {