GCMemcardDirectory: Decode and strip strings for GCI filenames.

Source/Core/Core/HW/GCMemcard/GCMemcard.cpp

@@ -304,7 +304,7 @@ void GCMemcard::UpdateBat(const BlockAlloc& bat)
 
 bool GCMemcard::IsShiftJIS() const
 {
-  return m_header_block.m_data.m_encoding != 0;
+  return m_header_block.IsShiftJIS();
 }
 
 bool GCMemcard::Save()
@@ -1274,15 +1274,6 @@ DEntry::DEntry()
   memset(reinterpret_cast<u8*>(this), 0xFF, DENTRY_SIZE);
 }
 
-std::string DEntry::GCI_FileName() const
-{
-  std::string filename =
-      std::string(reinterpret_cast<const char*>(m_makercode.data()), m_makercode.size()) + '-' +
-      std::string(reinterpret_cast<const char*>(m_gamecode.data()), m_gamecode.size()) + '-' +
-      reinterpret_cast<const char*>(m_filename.data()) + ".gci";
-  return Common::EscapeFileName(filename);
-}
-
 void Header::FixChecksums()
 {
   std::tie(m_checksum, m_checksum_inv) = CalculateChecksums();
@@ -1324,6 +1315,11 @@ GCMemcardErrorCode Header::CheckForErrors(u16 card_size_mbits) const
   return error_code;
 }
 
+bool Header::IsShiftJIS() const
+{
+  return m_data.m_encoding != 0;
+}
+
 Directory::Directory()
 {
   memset(reinterpret_cast<u8*>(this), 0xFF, BLOCK_SIZE);

Source/Core/Core/HW/GCMemcard/GCMemcard.h

@@ -231,6 +231,8 @@ struct Header
   std::pair<u16, u16> CalculateChecksums() const;
 
   GCMemcardErrorCode CheckForErrors(u16 card_size_mbits) const;
+
+  bool IsShiftJIS() const;
 };
 static_assert(sizeof(Header) == BLOCK_SIZE);
 static_assert(std::is_trivially_copyable_v<Header>);
@@ -239,9 +241,6 @@ struct DEntry
 {
   DEntry();
 
-  // TODO: This probably shouldn't be here at all?
-  std::string GCI_FileName() const;
-
   static constexpr std::array<u8, 4> UNINITIALIZED_GAMECODE{{0xFF, 0xFF, 0xFF, 0xFF}};
 
   // 4 bytes at 0x00: Gamecode

Source/Core/Core/HW/GCMemcard/GCMemcardDirectory.cpp

@@ -9,6 +9,7 @@
 #include <memory>
 #include <mutex>
 #include <string>
+#include <string_view>
 #include <vector>
 
 #include <fmt/format.h>
@@ -39,6 +40,28 @@
 
 static const char* MC_HDR = "MC_SYSTEM_AREA";
 
+static std::string GenerateDefaultGCIFilename(const Memcard::DEntry& entry,
+                                              bool card_encoding_is_shift_jis)
+{
+  const auto string_decoder = card_encoding_is_shift_jis ? SHIFTJISToUTF8 : CP1252ToUTF8;
+  const auto strip_null = [](const std::string_view& s) {
+    auto offset = s.find('\0');
+    if (offset == std::string_view::npos)
+      return s;
+    return s.substr(0, offset);
+  };
+
+  const std::string_view makercode(reinterpret_cast<const char*>(entry.m_makercode.data()),
+                                   entry.m_makercode.size());
+  const std::string_view gamecode(reinterpret_cast<const char*>(entry.m_gamecode.data()),
+                                  entry.m_gamecode.size());
+  const std::string_view filename(reinterpret_cast<const char*>(entry.m_filename.data()),
+                                  entry.m_filename.size());
+  return Common::EscapeFileName(fmt::format("{}-{}-{}.gci", strip_null(string_decoder(makercode)),
+                                            strip_null(string_decoder(gamecode)),
+                                            strip_null(string_decoder(filename))));
+}
+
 bool GCMemcardDirectory::LoadGCI(Memcard::GCIFile gci)
 {
   // check if any already loaded file has the same internal name as the new file
@@ -102,7 +125,8 @@ bool GCMemcardDirectory::LoadGCI(Memcard::GCIFile gci)
 
 // This is only used by NetPlay but it made sense to put it here to keep the relevant code together
 std::vector<std::string> GCMemcardDirectory::GetFileNamesForGameID(const std::string& directory,
-                                                                   const std::string& game_id)
+                                                                   const std::string& game_id,
+                                                                   bool card_encoding_is_shift_jis)
 {
   std::vector<std::string> filenames;
 
@@ -123,7 +147,8 @@ std::vector<std::string> GCMemcardDirectory::GetFileNamesForGameID(const std::st
     if (!gci_file.ReadBytes(&gci.m_gci_header, Memcard::DENTRY_SIZE))
       continue;
 
-    const std::string gci_filename = gci.m_gci_header.GCI_FileName();
+    const std::string gci_filename =
+        GenerateDefaultGCIFilename(gci.m_gci_header, card_encoding_is_shift_jis);
     if (std::find(loaded_saves.begin(), loaded_saves.end(), gci_filename) != loaded_saves.end())
       continue;
 
@@ -614,7 +639,8 @@ void GCMemcardDirectory::FlushToFile()
         }
         if (save.m_filename.empty())
         {
-          std::string default_save_name = m_save_directory + save.m_gci_header.GCI_FileName();
+          std::string default_save_name =
+              m_save_directory + GenerateDefaultGCIFilename(save.m_gci_header, m_hdr.IsShiftJIS());
 
           // Check to see if another file is using the same name
           // This seems unlikely except in the case of file corruption

Source/Core/Core/HW/GCMemcard/GCMemcardDirectory.h

@@ -32,7 +32,8 @@ public:
   GCMemcardDirectory& operator=(GCMemcardDirectory&&) = delete;
 
   static std::vector<std::string> GetFileNamesForGameID(const std::string& directory,
-                                                        const std::string& game_id);
+                                                        const std::string& game_id,
+                                                        bool card_encoding_is_shift_jis);
   void FlushToFile();
   void FlushThread();
   s32 Read(u32 src_address, s32 length, u8* dest_address) override;

Source/Core/Core/NetPlayServer.cpp

@@ -1686,7 +1686,8 @@ bool NetPlayServer::SyncSaveData(const SaveSyncInfo& sync_info)
     return true;
 
   const auto game_region = sync_info.game->GetRegion();
-  const std::string region = Config::GetDirectoryForRegion(Config::ToGameCubeRegion(game_region));
+  const auto gamecube_region = Config::ToGameCubeRegion(game_region);
+  const std::string region = Config::GetDirectoryForRegion(gamecube_region);
 
   for (ExpansionInterface::Slot slot : ExpansionInterface::MEMCARD_SLOTS)
   {
@@ -1733,8 +1734,8 @@ bool NetPlayServer::SyncSaveData(const SaveSyncInfo& sync_info)
 
       if (File::IsDirectory(path))
       {
-        std::vector<std::string> files =
+        std::vector<std::string> files = GCMemcardDirectory::GetFileNamesForGameID(
-            GCMemcardDirectory::GetFileNamesForGameID(path + DIR_SEP, sync_info.game->GetGameID());
+            path + DIR_SEP, sync_info.game->GetGameID(), gamecube_region == DiscIO::Region::NTSC_J);
 
         pac << static_cast<u8>(files.size());