NandPaths: Return paths that are relative to Wii NAND

Since all FS access will go through the new FS interface (PR #6421)
in order to keep track of metadata properly, there is no need to return
absolute paths anymore.

In fact, returning host paths is a roadblock to using the FS interface.

This starts the migration work by adding a way to get paths that are
relative to the Wii NAND instead of always getting absolute paths
on the host FS.

To prepare for future changes, this commit also makes returned paths
canonical by removing the trailing slash when it's unneeded.

Eventually, once everything has been migrated to the new interface,
we can remove the "from" parameter.

11 files changed, 60 insertions, 41 deletions

diff --git a/Source/Core/Common/NandPaths.cpp b/Source/Core/Common/NandPaths.cpp
index b670be635d..336c1bb7bb 100644
--- a/Source/Core/Common/NandPaths.cpp
+++ b/Source/Core/Common/NandPaths.cpp
@@ -21,41 +21,46 @@ std::string RootUserPath(FromWhichRoot from)
   return File::GetUserPath(idx);
 }
 
-std::string GetImportTitlePath(u64 title_id, FromWhichRoot from)
+static std::string RootUserPath(std::optional<FromWhichRoot> from)
+{
+  return from ? RootUserPath(*from) : "";
+}
+
+std::string GetImportTitlePath(u64 title_id, std::optional<FromWhichRoot> from)
 {
   return RootUserPath(from) + StringFromFormat("/import/%08x/%08x",
                                                static_cast<u32>(title_id >> 32),
                                                static_cast<u32>(title_id));
 }
 
-std::string GetTicketFileName(u64 title_id, FromWhichRoot from)
+std::string GetTicketFileName(u64 title_id, std::optional<FromWhichRoot> from)
 {
   return StringFromFormat("%s/ticket/%08x/%08x.tik", RootUserPath(from).c_str(),
                           static_cast<u32>(title_id >> 32), static_cast<u32>(title_id));
 }
 
-std::string GetTitlePath(u64 title_id, FromWhichRoot from)
+std::string GetTitlePath(u64 title_id, std::optional<FromWhichRoot> from)
 {
-  return StringFromFormat("%s/title/%08x/%08x/", RootUserPath(from).c_str(),
+  return StringFromFormat("%s/title/%08x/%08x", RootUserPath(from).c_str(),
                           static_cast<u32>(title_id >> 32), static_cast<u32>(title_id));
 }
 
-std::string GetTitleDataPath(u64 title_id, FromWhichRoot from)
+std::string GetTitleDataPath(u64 title_id, std::optional<FromWhichRoot> from)
 {
-  return GetTitlePath(title_id, from) + "data/";
+  return GetTitlePath(title_id, from) + "/data";
 }
 
-std::string GetTitleContentPath(u64 title_id, FromWhichRoot from)
+std::string GetTitleContentPath(u64 title_id, std::optional<FromWhichRoot> from)
 {
-  return GetTitlePath(title_id, from) + "content/";
+  return GetTitlePath(title_id, from) + "/content";
 }
 
-std::string GetTMDFileName(u64 title_id, FromWhichRoot from)
+std::string GetTMDFileName(u64 title_id, std::optional<FromWhichRoot> from)
 {
-  return GetTitleContentPath(title_id, from) + "title.tmd";
+  return GetTitleContentPath(title_id, from) + "/title.tmd";
 }
 
-bool IsTitlePath(const std::string& path, FromWhichRoot from, u64* title_id)
+bool IsTitlePath(const std::string& path, std::optional<FromWhichRoot> from, u64* title_id)
 {
   std::string expected_prefix = RootUserPath(from) + "/title/";
   if (!StringBeginsWith(path, expected_prefix))
diff --git a/Source/Core/Common/NandPaths.h b/Source/Core/Common/NandPaths.h
index 5a1dcffce4..068a240f43 100644
--- a/Source/Core/Common/NandPaths.h
+++ b/Source/Core/Common/NandPaths.h
@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <optional>
 #include <string>
 
 #include "Common/CommonTypes.h"
@@ -18,17 +19,22 @@ enum FromWhichRoot
 
 std::string RootUserPath(FromWhichRoot from);
 
+// The following functions return paths relative to the NAND root.
+// If a FromWhichRoot is passed, the NAND root on the host filesystem will be prepended to the path.
+// TODO: remove the from parameter after all code is migrated off direct FS access.
+
 // Returns /import/%08x/%08x. Intended for use by ES.
-std::string GetImportTitlePath(u64 title_id, FromWhichRoot from = FROM_SESSION_ROOT);
+std::string GetImportTitlePath(u64 title_id, std::optional<FromWhichRoot> from = {});
 
-std::string GetTicketFileName(u64 title_id, FromWhichRoot from);
-std::string GetTitlePath(u64 title_id, FromWhichRoot from);
-std::string GetTitleDataPath(u64 title_id, FromWhichRoot from);
-std::string GetTitleContentPath(u64 title_id, FromWhichRoot from);
-std::string GetTMDFileName(u64 title_id, FromWhichRoot from);
+std::string GetTicketFileName(u64 title_id, std::optional<FromWhichRoot> from = {});
+std::string GetTitlePath(u64 title_id, std::optional<FromWhichRoot> from = {});
+std::string GetTitleDataPath(u64 title_id, std::optional<FromWhichRoot> from = {});
+std::string GetTitleContentPath(u64 title_id, std::optional<FromWhichRoot> from = {});
+std::string GetTMDFileName(u64 title_id, std::optional<FromWhichRoot> from = {});
 
 // Returns whether a path is within an installed title's directory.
-bool IsTitlePath(const std::string& path, FromWhichRoot from, u64* title_id = nullptr);
+bool IsTitlePath(const std::string& path, std::optional<FromWhichRoot> from = {},
+                 u64* title_id = nullptr);
 
 // Escapes characters that are invalid or have special meanings in the host file system
 std::string EscapeFileName(const std::string& filename);
diff --git a/Source/Core/Core/Boot/Boot.cpp b/Source/Core/Core/Boot/Boot.cpp
index f93b584251..d38ec6ad59 100644
--- a/Source/Core/Core/Boot/Boot.cpp
+++ b/Source/Core/Core/Boot/Boot.cpp
@@ -472,7 +472,7 @@ void StateFlags::UpdateChecksum()
 void UpdateStateFlags(std::function<void(StateFlags*)> update_function)
 {
   const std::string file_path =
-      Common::GetTitleDataPath(Titles::SYSTEM_MENU, Common::FROM_SESSION_ROOT) + WII_STATE;
+      Common::GetTitleDataPath(Titles::SYSTEM_MENU, Common::FROM_SESSION_ROOT) + "/" WII_STATE;
 
   File::IOFile file;
   StateFlags state;
diff --git a/Source/Core/Core/Boot/Boot_BS2Emu.cpp b/Source/Core/Core/Boot/Boot_BS2Emu.cpp
index f426175e58..dc4d5b91e8 100644
--- a/Source/Core/Core/Boot/Boot_BS2Emu.cpp
+++ b/Source/Core/Core/Boot/Boot_BS2Emu.cpp
@@ -227,7 +227,7 @@ bool CBoot::SetupWiiMemory()
   SettingsHandler gen;
   std::string serno;
   const std::string settings_file_path(
-      Common::GetTitleDataPath(Titles::SYSTEM_MENU, Common::FROM_SESSION_ROOT) + WII_SETTING);
+      Common::GetTitleDataPath(Titles::SYSTEM_MENU, Common::FROM_SESSION_ROOT) + "/" WII_SETTING);
   if (File::Exists(settings_file_path) && gen.Open(settings_file_path))
   {
     serno = gen.GetValue("SERNO");
@@ -328,7 +328,7 @@ bool CBoot::SetupWiiMemory()
 static void WriteEmptyPlayRecord()
 {
   const std::string file_path =
-      Common::GetTitleDataPath(Titles::SYSTEM_MENU, Common::FROM_SESSION_ROOT) + "play_rec.dat";
+      Common::GetTitleDataPath(Titles::SYSTEM_MENU, Common::FROM_SESSION_ROOT) + "/play_rec.dat";
   File::IOFile playrec_file(file_path, "r+b");
   std::vector<u8> empty_record(0x80);
   playrec_file.WriteBytes(empty_record.data(), empty_record.size());
diff --git a/Source/Core/Core/HW/WiiSaveCrypted.cpp b/Source/Core/Core/HW/WiiSaveCrypted.cpp
index 835ff9b980..28c9150b34 100644
--- a/Source/Core/Core/HW/WiiSaveCrypted.cpp
+++ b/Source/Core/Core/HW/WiiSaveCrypted.cpp
@@ -181,7 +181,7 @@ void CWiiSaveCrypted::ReadHDR()
     m_valid = false;
     return;
   }
-  std::string banner_file_path = m_wii_title_path + "banner.bin";
+  std::string banner_file_path = m_wii_title_path + "/banner.bin";
   if (!File::Exists(banner_file_path) ||
       AskYesNoT("%s already exists. Consider making a backup of the current save files before "
                 "overwriting.\nOverwrite now?",
@@ -203,7 +203,7 @@ void CWiiSaveCrypted::WriteHDR()
     return;
   memset(&m_header, 0, HEADER_SZ);
 
-  std::string banner_file_path = m_wii_title_path + "banner.bin";
+  std::string banner_file_path = m_wii_title_path + "/banner.bin";
   u32 banner_size = static_cast<u32>(File::GetSize(banner_file_path));
   m_header.hdr.BannerSize = Common::swap32(banner_size);
 
@@ -347,7 +347,7 @@ void CWiiSaveCrypted::ImportWiiSaveFiles()
       // Special characters in path components will be escaped such as /../
       std::string file_path = Common::EscapePath(reinterpret_cast<const char*>(file_hdr_tmp.name));
 
-      std::string file_path_full = m_wii_title_path + file_path;
+      std::string file_path_full = m_wii_title_path + '/' + file_path;
       File::CreateFullPath(file_path_full);
       const File::FileInfo file_info(file_path_full);
       if (file_hdr_tmp.type == 1)
@@ -585,7 +585,7 @@ bool CWiiSaveCrypted::getPaths(bool for_export)
       return false;
     }
 
-    if (!File::Exists(m_wii_title_path + "banner.bin"))
+    if (!File::Exists(m_wii_title_path + "/banner.bin"))
     {
       m_valid = false;
       ERROR_LOG(CONSOLE, "No banner file found for title %s", game_id);
diff --git a/Source/Core/Core/IOS/ES/NandUtils.cpp b/Source/Core/Core/IOS/ES/NandUtils.cpp
index 06c6efdf29..1b332bf97b 100644
--- a/Source/Core/Core/IOS/ES/NandUtils.cpp
+++ b/Source/Core/Core/IOS/ES/NandUtils.cpp
@@ -42,7 +42,8 @@ static IOS::ES::TMDReader FindTMD(u64 title_id, const std::string& tmd_path)
 
 IOS::ES::TMDReader ES::FindImportTMD(u64 title_id) const
 {
-  return FindTMD(title_id, Common::GetImportTitlePath(title_id) + "/content/title.tmd");
+  return FindTMD(title_id, Common::GetImportTitlePath(title_id, Common::FROM_SESSION_ROOT) +
+                               "/content/title.tmd");
 }
 
 IOS::ES::TMDReader ES::FindInstalledTMD(u64 title_id) const
@@ -218,7 +219,8 @@ bool ES::InitImport(u64 title_id)
   // IOS moves the title content directory to /import if the TMD exists during an import.
   if (File::Exists(Common::GetTMDFileName(title_id, Common::FROM_SESSION_ROOT)))
   {
-    const std::string import_content_dir = Common::GetImportTitlePath(title_id) + "/content";
+    const std::string import_content_dir =
+        Common::GetImportTitlePath(title_id, Common::FROM_SESSION_ROOT) + "/content";
     File::CreateFullPath(import_content_dir);
     if (!File::Rename(content_dir, import_content_dir))
     {
@@ -233,7 +235,8 @@ bool ES::InitImport(u64 title_id)
 bool ES::FinishImport(const IOS::ES::TMDReader& tmd)
 {
   const u64 title_id = tmd.GetTitleId();
-  const std::string import_content_dir = Common::GetImportTitlePath(title_id) + "/content";
+  const std::string import_content_dir =
+      Common::GetImportTitlePath(title_id, Common::FROM_SESSION_ROOT) + "/content";
 
   // Remove everything not listed in the TMD.
   std::unordered_set<std::string> expected_entries = {"title.tmd"};
@@ -274,7 +277,8 @@ bool ES::WriteImportTMD(const IOS::ES::TMDReader& tmd)
       return false;
   }
 
-  const std::string dest = Common::GetImportTitlePath(tmd.GetTitleId()) + "/content/title.tmd";
+  const std::string dest = Common::GetImportTitlePath(tmd.GetTitleId(), Common::FROM_SESSION_ROOT) +
+                           "/content/title.tmd";
   return File::Rename(tmd_path, dest);
 }
 
@@ -282,7 +286,8 @@ void ES::FinishStaleImport(u64 title_id)
 {
   const auto import_tmd = FindImportTMD(title_id);
   if (!import_tmd.IsValid())
-    File::DeleteDirRecursively(Common::GetImportTitlePath(title_id) + "/content");
+    File::DeleteDirRecursively(Common::GetImportTitlePath(title_id, Common::FROM_SESSION_ROOT) +
+                               "/content");
   else
     FinishImport(import_tmd);
 }
@@ -305,7 +310,7 @@ std::string ES::GetContentPath(const u64 title_id, const IOS::ES::Content& conte
     return content_map.GetFilenameFromSHA1(content.sha1).value_or("");
 
   return Common::GetTitleContentPath(title_id, Common::FROM_SESSION_ROOT) +
-         StringFromFormat("%08x.app", content.id);
+         StringFromFormat("/%08x.app", content.id);
 }
 }  // namespace Device
 }  // namespace HLE
diff --git a/Source/Core/Core/IOS/ES/TitleManagement.cpp b/Source/Core/Core/IOS/ES/TitleManagement.cpp
index 2496f854f7..1bb9a1a752 100644
--- a/Source/Core/Core/IOS/ES/TitleManagement.cpp
+++ b/Source/Core/Core/IOS/ES/TitleManagement.cpp
@@ -342,7 +342,8 @@ static bool CheckIfContentHashMatches(const std::vector<u8>& content, const IOS:
 
 static std::string GetImportContentPath(u64 title_id, u32 content_id)
 {
-  return Common::GetImportTitlePath(title_id) + StringFromFormat("/content/%08x.app", content_id);
+  return Common::GetImportTitlePath(title_id, Common::FROM_SESSION_ROOT) +
+         StringFromFormat("/content/%08x.app", content_id);
 }
 
 ReturnCode ES::ImportContentEnd(Context& context, u32 content_fd)
@@ -604,7 +605,7 @@ ReturnCode ES::DeleteContent(u64 title_id, u32 content_id) const
     return ES_EINVAL;
 
   if (!File::Delete(Common::GetTitleContentPath(title_id, Common::FROM_SESSION_ROOT) +
-                    StringFromFormat("%08x.app", content_id)))
+                    StringFromFormat("/%08x.app", content_id)))
   {
     return FS_ENOENT;
   }
diff --git a/Source/Core/Core/IOS/Network/KD/NetKDRequest.cpp b/Source/Core/Core/IOS/Network/KD/NetKDRequest.cpp
index a36ccf537a..ce3f202ddc 100644
--- a/Source/Core/Core/IOS/Network/KD/NetKDRequest.cpp
+++ b/Source/Core/Core/IOS/Network/KD/NetKDRequest.cpp
@@ -83,7 +83,8 @@ IPCCommandResult NetKDRequest::IOCtl(const IOCtlRequest& request)
     if (config.CreationStage() == NWC24::NWC24Config::NWC24_IDCS_INITIAL)
     {
       const std::string settings_file_path(
-          Common::GetTitleDataPath(Titles::SYSTEM_MENU, Common::FROM_SESSION_ROOT) + WII_SETTING);
+          Common::GetTitleDataPath(Titles::SYSTEM_MENU, Common::FROM_SESSION_ROOT) +
+          "/" WII_SETTING);
       SettingsHandler gen;
       std::string area, model;
       bool got_settings = false;
diff --git a/Source/Core/Core/Movie.cpp b/Source/Core/Core/Movie.cpp
index bf3b0c099f..980e75ee82 100644
--- a/Source/Core/Core/Movie.cpp
+++ b/Source/Core/Core/Movie.cpp
@@ -1384,8 +1384,8 @@ void GetSettings()
   if (SConfig::GetInstance().bWii)
   {
     u64 title_id = SConfig::GetInstance().GetTitleID();
-    s_bClearSave =
-        !File::Exists(Common::GetTitleDataPath(title_id, Common::FROM_SESSION_ROOT) + "banner.bin");
+    s_bClearSave = !File::Exists(Common::GetTitleDataPath(title_id, Common::FROM_SESSION_ROOT) +
+                                 "/banner.bin");
   }
   else
   {
diff --git a/Source/Core/Core/WiiRoot.cpp b/Source/Core/Core/WiiRoot.cpp
index a705801fc1..8058ab2685 100644
--- a/Source/Core/Core/WiiRoot.cpp
+++ b/Source/Core/Core/WiiRoot.cpp
@@ -36,7 +36,7 @@ static void InitializeDeterministicWiiSaves()
     else
     {
       // TODO: Check for the actual save data
-      Movie::SetClearSave(!File::Exists(user_save_path + "banner.bin"));
+      Movie::SetClearSave(!File::Exists(user_save_path + "/banner.bin"));
     }
   }
 
@@ -44,7 +44,7 @@ static void InitializeDeterministicWiiSaves()
       (Movie::IsMovieActive() && !Movie::IsStartingFromClearSave()))
   {
     // Copy the current user's save to the Blank NAND
-    if (File::Exists(user_save_path + "banner.bin"))
+    if (File::Exists(user_save_path + "/banner.bin"))
     {
       File::CopyDir(user_save_path, save_path);
     }
@@ -86,10 +86,10 @@ void ShutdownWiiRoot()
     std::string user_backup_path = File::GetUserPath(D_BACKUP_IDX) +
                                    StringFromFormat("%08x/%08x/", static_cast<u32>(title_id >> 32),
                                                     static_cast<u32>(title_id));
-    if (File::Exists(save_path + "banner.bin") && SConfig::GetInstance().bEnableMemcardSdWriting)
+    if (File::Exists(save_path + "/banner.bin") && SConfig::GetInstance().bEnableMemcardSdWriting)
     {
       // Backup the existing save just in case it's still needed.
-      if (File::Exists(user_save_path + "banner.bin"))
+      if (File::Exists(user_save_path + "/banner.bin"))
       {
         if (File::Exists(user_backup_path))
           File::DeleteDirRecursively(user_backup_path);
diff --git a/Source/Core/DiscIO/WiiSaveBanner.cpp b/Source/Core/DiscIO/WiiSaveBanner.cpp
index a248151e44..444cb0590d 100644
--- a/Source/Core/DiscIO/WiiSaveBanner.cpp
+++ b/Source/Core/DiscIO/WiiSaveBanner.cpp
@@ -25,7 +25,8 @@ constexpr unsigned int ICON_HEIGHT = 48;
 constexpr unsigned int ICON_SIZE = ICON_WIDTH * ICON_HEIGHT * 2;
 
 WiiSaveBanner::WiiSaveBanner(u64 title_id)
-    : WiiSaveBanner(Common::GetTitleDataPath(title_id, Common::FROM_CONFIGURED_ROOT) + "banner.bin")
+    : WiiSaveBanner(Common::GetTitleDataPath(title_id, Common::FROM_CONFIGURED_ROOT) +
+                    "/banner.bin")
 {
 }