file_util: Use an enum class for GetUserPath()

Instead of using an unsigned int as a parameter and expecting a user to
always pass in the correct values, we can just convert the enum into an
enum class and use that type as the parameter type instead, which makes
the interface more type safe.

We also get rid of the bookkeeping "NUM_" element in the enum by just
using an unordered map. This function is generally low-frequency in
terms of calls (and I'd hope so, considering otherwise would mean we're
slamming the disk with IO all the time) so I'd consider this acceptable
in this case.

src/citra/citra.cpp

@@ -115,6 +115,18 @@ static void OnMessageReceived(const Network::ChatEntry& msg) {
     std::cout << std::endl << msg.nickname << ": " << msg.message << std::endl << std::endl;
 }
 
+static void InitializeLogging() {
+    Log::Filter log_filter(Log::Level::Debug);
+    log_filter.ParseFilterString(Settings::values.log_filter);
+    Log::SetGlobalFilter(log_filter);
+
+    Log::AddBackend(std::make_unique<Log::ColorConsoleBackend>());
+
+    const std::string& log_dir = FileUtil::GetUserPath(FileUtil::UserPath::LogDir);
+    FileUtil::CreateFullPath(log_dir);
+    Log::AddBackend(std::make_unique<Log::FileBackend>(log_dir + LOG_FILE));
+}
+
 /// Application entry point
 int main(int argc, char** argv) {
     Config config;
@@ -124,14 +136,7 @@ int main(int argc, char** argv) {
     std::string movie_record;
     std::string movie_play;
 
-    Log::Filter log_filter;
+    InitializeLogging();
-    log_filter.ParseFilterString(Settings::values.log_filter);
-    Log::SetGlobalFilter(log_filter);
-
-    Log::AddBackend(std::make_unique<Log::ColorConsoleBackend>());
-    FileUtil::CreateFullPath(FileUtil::GetUserPath(D_LOGS_IDX));
-    Log::AddBackend(
-        std::make_unique<Log::FileBackend>(FileUtil::GetUserPath(D_LOGS_IDX) + LOG_FILE));
 
     char* endarg;
 #ifdef _WIN32

src/citra/config.cpp

@@ -20,7 +20,7 @@
 
 Config::Config() {
     // TODO: Don't hardcode the path; let the frontend decide where to put the config files.
-    sdl2_config_loc = FileUtil::GetUserPath(D_CONFIG_IDX) + "sdl2-config.ini";
+    sdl2_config_loc = FileUtil::GetUserPath(FileUtil::UserPath::ConfigDir) + "sdl2-config.ini";
     sdl2_config = std::make_unique<INIReader>(sdl2_config_loc);
 
     Reload();

src/citra_qt/configuration/config.cpp

@@ -14,7 +14,7 @@
 
 Config::Config() {
     // TODO: Don't hardcode the path; let the frontend decide where to put the config files.
-    qt_config_loc = FileUtil::GetUserPath(D_CONFIG_IDX) + "qt-config.ini";
+    qt_config_loc = FileUtil::GetUserPath(FileUtil::UserPath::ConfigDir) + "qt-config.ini";
     FileUtil::CreateFullPath(qt_config_loc);
     qt_config = new QSettings(QString::fromStdString(qt_config_loc), QSettings::IniFormat);
 

src/citra_qt/configuration/configure_debug.cpp

@@ -19,7 +19,7 @@ ConfigureDebug::ConfigureDebug(QWidget* parent) : QWidget(parent), ui(new Ui::Co
     ui->setupUi(this);
     this->setConfiguration();
     connect(ui->open_log_button, &QPushButton::pressed, []() {
-        QString path = QString::fromStdString(FileUtil::GetUserPath(D_LOGS_IDX));
+        QString path = QString::fromStdString(FileUtil::GetUserPath(FileUtil::UserPath::LogDir));
         QDesktopServices::openUrl(QUrl::fromLocalFile(path));
     });
     ui->toggle_cpu_jit->setEnabled(!Core::System::GetInstance().IsPoweredOn());

src/citra_qt/game_list.cpp

@@ -715,7 +715,8 @@ void GameListWorker::run() {
     stop_processing = false;
     for (UISettings::GameDir& game_dir : game_dirs) {
         if (game_dir.path == "INSTALLED") {
-            QString path = QString::fromStdString(FileUtil::GetUserPath(D_SDMC_IDX)) +
+            QString path =
+                QString::fromStdString(FileUtil::GetUserPath(FileUtil::UserPath::SDMCDir)) +
                 "Nintendo "
                 "3DS/00000000000000000000000000000000/"
                 "00000000000000000000000000000000/title/00040000";
@@ -724,7 +725,8 @@ void GameListWorker::run() {
             emit DirEntryReady({game_list_dir});
             AddFstEntriesToGameList(path.toStdString(), 2, game_list_dir);
         } else if (game_dir.path == "SYSTEM") {
-            QString path = QString::fromStdString(FileUtil::GetUserPath(D_NAND_IDX)) +
+            QString path =
+                QString::fromStdString(FileUtil::GetUserPath(FileUtil::UserPath::NANDDir)) +
                 "00000000000000000000000000000000/title/00040010";
             watch_list.append(path);
             GameListDir* game_list_dir = new GameListDir(game_dir, GameListItemType::SystemDir);

src/citra_qt/game_list_p.h

@@ -172,13 +172,13 @@ public:
             QString second_name = QString::fromStdString(filename + extension);
             static QRegExp installed_pattern(
                 QString::fromStdString(
-                    FileUtil::GetUserPath(D_SDMC_IDX) +
+                    FileUtil::GetUserPath(FileUtil::UserPath::SDMCDir) +
                     "Nintendo "
                     "3DS/00000000000000000000000000000000/00000000000000000000000000000000/"
                     "title/0004000(0|e)/[0-9a-f]{8}/content/")
                     .replace("\\", "\\\\"));
             static QRegExp system_pattern(
-                QString::fromStdString(FileUtil::GetUserPath(D_NAND_IDX) +
+                QString::fromStdString(FileUtil::GetUserPath(FileUtil::UserPath::NANDDir) +
                                        "00000000000000000000000000000000/"
                                        "title/00040010/[0-9a-f]{8}/content/")
                     .replace("\\", "\\\\"));

src/citra_qt/main.cpp

@@ -102,13 +102,18 @@ void GMainWindow::ShowTelemetryCallout() {
 
 const int GMainWindow::max_recent_files_item;
 
-GMainWindow::GMainWindow() : config(new Config()), emu_thread(nullptr) {
+static void InitializeLogging() {
     Log::Filter log_filter;
     log_filter.ParseFilterString(Settings::values.log_filter);
     Log::SetGlobalFilter(log_filter);
-    FileUtil::CreateFullPath(FileUtil::GetUserPath(D_LOGS_IDX));
+
-    Log::AddBackend(
+    const std::string& log_dir = FileUtil::GetUserPath(FileUtil::UserPath::LogDir);
-        std::make_unique<Log::FileBackend>(FileUtil::GetUserPath(D_LOGS_IDX) + LOG_FILE));
+    FileUtil::CreateFullPath(log_dir);
+    Log::AddBackend(std::make_unique<Log::FileBackend>(log_dir + LOG_FILE));
+}
+
+GMainWindow::GMainWindow() : config(new Config()), emu_thread(nullptr) {
+    InitializeLogging();
     Debugger::ToggleConsole();
     Settings::LogSettings();
 
@@ -880,7 +885,7 @@ void GMainWindow::OnGameListOpenFolder(u64 program_id, GameListOpenTarget target
     switch (target) {
     case GameListOpenTarget::SAVE_DATA: {
         open_target = "Save Data";
-        std::string sdmc_dir = FileUtil::GetUserPath(D_SDMC_IDX);
+        std::string sdmc_dir = FileUtil::GetUserPath(FileUtil::UserPath::SDMCDir);
         path = FileSys::ArchiveSource_SDSaveData::GetSaveDataPathFor(sdmc_dir, program_id);
         break;
     }
@@ -931,13 +936,13 @@ void GMainWindow::OnGameListOpenDirectory(QString directory) {
     QString path;
     if (directory == "INSTALLED") {
         path =
-            QString::fromStdString(FileUtil::GetUserPath(D_SDMC_IDX).c_str() +
+            QString::fromStdString(FileUtil::GetUserPath(FileUtil::UserPath::SDMCDir).c_str() +
                                    std::string("Nintendo "
                                                "3DS/00000000000000000000000000000000/"
                                                "00000000000000000000000000000000/title/00040000"));
     } else if (directory == "SYSTEM") {
         path =
-            QString::fromStdString(FileUtil::GetUserPath(D_NAND_IDX).c_str() +
+            QString::fromStdString(FileUtil::GetUserPath(FileUtil::UserPath::NANDDir).c_str() +
                                    std::string("00000000000000000000000000000000/title/00040010"));
     } else {
         path = directory;

src/common/common_paths.h

@@ -30,7 +30,7 @@
 #define USA_DIR "USA"
 #define JAP_DIR "JAP"
 
-// Subdirs in the User dir returned by GetUserPath(D_USER_IDX)
+// Subdirs in the User dir returned by GetUserPath(UserPath::UserDir)
 #define CONFIG_DIR "config"
 #define CACHE_DIR "cache"
 #define SDMC_DIR "sdmc"
@@ -39,10 +39,10 @@
 #define LOG_DIR "log"
 
 // Filenames
-// Files in the directory returned by GetUserPath(D_LOGS_IDX)
+// Files in the directory returned by GetUserPath(UserPath::LogDir)
 #define LOG_FILE "citra_log.txt"
 
-// Files in the directory returned by GetUserPath(D_CONFIG_IDX)
+// Files in the directory returned by GetUserPath(UserPath::ConfigDir)
 #define EMU_CONFIG "emu.ini"
 #define DEBUGGER_CONFIG "debugger.ini"
 #define LOGGER_CONFIG "logger.ini"

src/common/file_util.cpp

@@ -4,6 +4,7 @@
 
 #include <array>
 #include <memory>
+#include <unordered_map>
 #include "common/assert.h"
 #include "common/common_funcs.h"
 #include "common/common_paths.h"
@@ -670,67 +671,68 @@ std::string GetSysDirectory() {
 
 // Returns a string with a Citra data dir or file in the user's home
 // directory. To be used in "multi-user" mode (that is, installed).
-const std::string& GetUserPath(const unsigned int DirIDX, const std::string& newPath) {
+const std::string& GetUserPath(UserPath path, const std::string& new_path) {
-    static std::string paths[NUM_PATH_INDICES];
+    static std::unordered_map<UserPath, std::string> paths;
+    auto& user_path = paths[UserPath::UserDir];
 
     // Set up all paths and files on the first run
-    if (paths[D_USER_IDX].empty()) {
+    if (user_path.empty()) {
 #ifdef _WIN32
-        paths[D_USER_IDX] = GetExeDirectory() + DIR_SEP USERDATA_DIR DIR_SEP;
+        user_path = GetExeDirectory() + DIR_SEP USERDATA_DIR DIR_SEP;
-        if (!FileUtil::IsDirectory(paths[D_USER_IDX])) {
+        if (!FileUtil::IsDirectory(user_path)) {
-            paths[D_USER_IDX] = AppDataRoamingDirectory() + DIR_SEP EMU_DATA_DIR DIR_SEP;
+            user_path = AppDataRoamingDirectory() + DIR_SEP EMU_DATA_DIR DIR_SEP;
         } else {
             LOG_INFO(Common_Filesystem, "Using the local user directory");
         }
 
-        paths[D_CONFIG_IDX] = paths[D_USER_IDX] + CONFIG_DIR DIR_SEP;
+        paths.emplace(UserPath::ConfigDir, user_path + CONFIG_DIR DIR_SEP);
-        paths[D_CACHE_IDX] = paths[D_USER_IDX] + CACHE_DIR DIR_SEP;
+        paths.emplace(UserPath::CacheDir, user_path + CACHE_DIR DIR_SEP);
 #else
         if (FileUtil::Exists(ROOT_DIR DIR_SEP USERDATA_DIR)) {
-            paths[D_USER_IDX] = ROOT_DIR DIR_SEP USERDATA_DIR DIR_SEP;
+            user_path = ROOT_DIR DIR_SEP USERDATA_DIR DIR_SEP;
-            paths[D_CONFIG_IDX] = paths[D_USER_IDX] + CONFIG_DIR DIR_SEP;
+            paths.emplace(UserPath::ConfigDir, user_path + CONFIG_DIR DIR_SEP);
-            paths[D_CACHE_IDX] = paths[D_USER_IDX] + CACHE_DIR DIR_SEP;
+            paths.emplace(UserPath::CacheDir, user_path + CACHE_DIR DIR_SEP);
         } else {
             std::string data_dir = GetUserDirectory("XDG_DATA_HOME");
             std::string config_dir = GetUserDirectory("XDG_CONFIG_HOME");
             std::string cache_dir = GetUserDirectory("XDG_CACHE_HOME");
 
-            paths[D_USER_IDX] = data_dir + DIR_SEP EMU_DATA_DIR DIR_SEP;
+            user_path = data_dir + DIR_SEP EMU_DATA_DIR DIR_SEP;
-            paths[D_CONFIG_IDX] = config_dir + DIR_SEP EMU_DATA_DIR DIR_SEP;
+            paths.emplace(UserPath::ConfigDir, config_dir + DIR_SEP EMU_DATA_DIR DIR_SEP);
-            paths[D_CACHE_IDX] = cache_dir + DIR_SEP EMU_DATA_DIR DIR_SEP;
+            paths.emplace(UserPath::CacheDir, cache_dir + DIR_SEP EMU_DATA_DIR DIR_SEP);
         }
 #endif
-        paths[D_SDMC_IDX] = paths[D_USER_IDX] + SDMC_DIR DIR_SEP;
+        paths.emplace(UserPath::SDMCDir, user_path + SDMC_DIR DIR_SEP);
-        paths[D_NAND_IDX] = paths[D_USER_IDX] + NAND_DIR DIR_SEP;
+        paths.emplace(UserPath::NANDDir, user_path + NAND_DIR DIR_SEP);
-        paths[D_SYSDATA_IDX] = paths[D_USER_IDX] + SYSDATA_DIR DIR_SEP;
+        paths.emplace(UserPath::SysDataDir, user_path + SYSDATA_DIR DIR_SEP);
         // TODO: Put the logs in a better location for each OS
-        paths[D_LOGS_IDX] = paths[D_USER_IDX] + LOG_DIR DIR_SEP;
+        paths.emplace(UserPath::LogDir, user_path + LOG_DIR DIR_SEP);
     }
 
-    if (!newPath.empty()) {
+    if (!new_path.empty()) {
-        if (!FileUtil::IsDirectory(newPath)) {
+        if (!FileUtil::IsDirectory(new_path)) {
-            LOG_ERROR(Common_Filesystem, "Invalid path specified {}", newPath);
+            LOG_ERROR(Common_Filesystem, "Invalid path specified {}", new_path);
-            return paths[DirIDX];
+            return paths[path];
         } else {
-            paths[DirIDX] = newPath;
+            paths[path] = new_path;
         }
 
-        switch (DirIDX) {
+        switch (path) {
-        case D_ROOT_IDX:
+        case UserPath::RootDir:
-            paths[D_USER_IDX] = paths[D_ROOT_IDX] + DIR_SEP;
+            user_path = paths[UserPath::RootDir] + DIR_SEP;
             break;
 
-        case D_USER_IDX:
+        case UserPath::UserDir:
-            paths[D_USER_IDX] = paths[D_ROOT_IDX] + DIR_SEP;
+            user_path = paths[UserPath::RootDir] + DIR_SEP;
-            paths[D_CONFIG_IDX] = paths[D_USER_IDX] + CONFIG_DIR DIR_SEP;
+            paths[UserPath::ConfigDir] = user_path + CONFIG_DIR DIR_SEP;
-            paths[D_CACHE_IDX] = paths[D_USER_IDX] + CACHE_DIR DIR_SEP;
+            paths[UserPath::CacheDir] = user_path + CACHE_DIR DIR_SEP;
-            paths[D_SDMC_IDX] = paths[D_USER_IDX] + SDMC_DIR DIR_SEP;
+            paths[UserPath::SDMCDir] = user_path + SDMC_DIR DIR_SEP;
-            paths[D_NAND_IDX] = paths[D_USER_IDX] + NAND_DIR DIR_SEP;
+            paths[UserPath::NANDDir] = user_path + NAND_DIR DIR_SEP;
             break;
         }
     }
 
-    return paths[DirIDX];
+    return paths[path];
 }
 
 size_t WriteStringToFile(bool text_file, const std::string& str, const char* filename) {

src/common/file_util.h

@@ -17,21 +17,20 @@
 #include "common/string_util.h"
 #endif
 
-// User directory indices for GetUserPath
-enum {
-    D_USER_IDX,
-    D_ROOT_IDX,
-    D_CONFIG_IDX,
-    D_CACHE_IDX,
-    D_SDMC_IDX,
-    D_NAND_IDX,
-    D_SYSDATA_IDX,
-    D_LOGS_IDX,
-    NUM_PATH_INDICES
-};
-
 namespace FileUtil {
 
+// User paths for GetUserPath
+enum class UserPath {
+    CacheDir,
+    ConfigDir,
+    LogDir,
+    NANDDir,
+    RootDir,
+    SDMCDir,
+    SysDataDir,
+    UserDir,
+};
+
 // FileSystem tree node/
 struct FSTEntry {
     bool isDirectory;
@@ -124,7 +123,7 @@ bool SetCurrentDir(const std::string& directory);
 
 // Returns a pointer to a string with a Citra data dir in the user's home
 // directory. To be used in "multi-user" mode (that is, installed).
-const std::string& GetUserPath(const unsigned int DirIDX, const std::string& newPath = "");
+const std::string& GetUserPath(UserPath path, const std::string& new_path = "");
 
 // Returns the path to where the sys file are
 std::string GetSysDirectory();

src/core/hle/service/am/am.cpp

@@ -441,11 +441,13 @@ std::string GetTitlePath(Service::FS::MediaType media_type, u64 tid) {
 
 std::string GetMediaTitlePath(Service::FS::MediaType media_type) {
     if (media_type == Service::FS::MediaType::NAND)
-        return fmt::format("{}{}/title/", FileUtil::GetUserPath(D_NAND_IDX), SYSTEM_ID);
+        return fmt::format("{}{}/title/", FileUtil::GetUserPath(FileUtil::UserPath::NANDDir),
+                           SYSTEM_ID);
 
     if (media_type == Service::FS::MediaType::SDMC)
-        return fmt::format("{}Nintendo 3DS/{}/{}/title/", FileUtil::GetUserPath(D_SDMC_IDX),
+        return fmt::format("{}Nintendo 3DS/{}/{}/title/",
-                           SYSTEM_ID, SDCARD_ID);
+                           FileUtil::GetUserPath(FileUtil::UserPath::SDMCDir), SYSTEM_ID,
+                           SDCARD_ID);
 
     if (media_type == Service::FS::MediaType::GameCard) {
         // TODO(shinyquagsire23): get current app parent folder if TID matches?

src/core/hle/service/apt/apt.cpp

@@ -172,7 +172,7 @@ bool Module::LoadLegacySharedFont() {
     // generated by the APT:U service. The best way to get is by dumping it from RAM. We've provided
     // a homebrew app to do this: https://github.com/citra-emu/3dsutils. Put the resulting file
     // "shared_font.bin" in the Citra "sysdata" directory.
-    std::string filepath = FileUtil::GetUserPath(D_SYSDATA_IDX) + SHARED_FONT;
+    std::string filepath = FileUtil::GetUserPath(FileUtil::UserPath::SysDataDir) + SHARED_FONT;
 
     FileUtil::CreateFullPath(filepath); // Create path if not already created
     FileUtil::IOFile file(filepath, "rb");

src/core/hle/service/fs/archive.cpp

@@ -572,9 +572,9 @@ ResultCode DeleteExtSaveData(MediaType media_type, u32 high, u32 low) {
 
     std::string media_type_directory;
     if (media_type == MediaType::NAND) {
-        media_type_directory = FileUtil::GetUserPath(D_NAND_IDX);
+        media_type_directory = FileUtil::GetUserPath(FileUtil::UserPath::NANDDir);
     } else if (media_type == MediaType::SDMC) {
-        media_type_directory = FileUtil::GetUserPath(D_SDMC_IDX);
+        media_type_directory = FileUtil::GetUserPath(FileUtil::UserPath::SDMCDir);
     } else {
         LOG_ERROR(Service_FS, "Unsupported media type {}", static_cast<u32>(media_type));
         return ResultCode(-1); // TODO(Subv): Find the right error code
@@ -593,7 +593,7 @@ ResultCode DeleteSystemSaveData(u32 high, u32 low) {
     // Construct the binary path to the archive first
     FileSys::Path path = FileSys::ConstructSystemSaveDataBinaryPath(high, low);
 
-    std::string nand_directory = FileUtil::GetUserPath(D_NAND_IDX);
+    std::string nand_directory = FileUtil::GetUserPath(FileUtil::UserPath::NANDDir);
     std::string base_path = FileSys::GetSystemSaveDataContainerPath(nand_directory);
     std::string systemsavedata_path = FileSys::GetSystemSaveDataPath(base_path, path);
     if (!FileUtil::DeleteDirRecursively(systemsavedata_path))
@@ -605,7 +605,7 @@ ResultCode CreateSystemSaveData(u32 high, u32 low) {
     // Construct the binary path to the archive first
     FileSys::Path path = FileSys::ConstructSystemSaveDataBinaryPath(high, low);
 
-    std::string nand_directory = FileUtil::GetUserPath(D_NAND_IDX);
+    std::string nand_directory = FileUtil::GetUserPath(FileUtil::UserPath::NANDDir);
     std::string base_path = FileSys::GetSystemSaveDataContainerPath(nand_directory);
     std::string systemsavedata_path = FileSys::GetSystemSaveDataPath(base_path, path);
     if (!FileUtil::CreateFullPath(systemsavedata_path))
@@ -617,8 +617,8 @@ void RegisterArchiveTypes() {
     // TODO(Subv): Add the other archive types (see here for the known types:
     // http://3dbrew.org/wiki/FS:OpenArchive#Archive_idcodes).
 
-    std::string sdmc_directory = FileUtil::GetUserPath(D_SDMC_IDX);
+    std::string sdmc_directory = FileUtil::GetUserPath(FileUtil::UserPath::SDMCDir);
-    std::string nand_directory = FileUtil::GetUserPath(D_NAND_IDX);
+    std::string nand_directory = FileUtil::GetUserPath(FileUtil::UserPath::NANDDir);
     auto sdmc_factory = std::make_unique<FileSys::ArchiveFactory_SDMC>(sdmc_directory);
     if (sdmc_factory->Initialize())
         RegisterArchiveType(std::move(sdmc_factory), ArchiveIdCode::SDMC);

src/core/hw/aes/key.cpp

@@ -70,7 +70,7 @@ AESKey HexToKey(const std::string& hex) {
 }
 
 void LoadPresetKeys() {
-    const std::string filepath = FileUtil::GetUserPath(D_SYSDATA_IDX) + AES_KEYS;
+    const std::string filepath = FileUtil::GetUserPath(FileUtil::UserPath::SysDataDir) + AES_KEYS;
     FileUtil::CreateFullPath(filepath); // Create path if not already created
     std::ifstream file;
     OpenFStream(file, filepath, std::ios_base::in);

src/core/telemetry_session.cpp

@@ -45,7 +45,8 @@ static u64 GenerateTelemetryId() {
 
 u64 GetTelemetryId() {
     u64 telemetry_id{};
-    const std::string filename{FileUtil::GetUserPath(D_CONFIG_IDX) + "telemetry_id"};
+    const std::string filename{FileUtil::GetUserPath(FileUtil::UserPath::ConfigDir) +
+                               "telemetry_id"};
 
     if (FileUtil::Exists(filename)) {
         FileUtil::IOFile file(filename, "rb");
@@ -69,7 +70,8 @@ u64 GetTelemetryId() {
 
 u64 RegenerateTelemetryId() {
     const u64 new_telemetry_id{GenerateTelemetryId()};
-    const std::string filename{FileUtil::GetUserPath(D_CONFIG_IDX) + "telemetry_id"};
+    const std::string filename{FileUtil::GetUserPath(FileUtil::UserPath::ConfigDir) +
+                               "telemetry_id"};
 
     FileUtil::IOFile file(filename, "wb");
     if (!file.IsOpen()) {