Refactor DSi_NAND (#1844)

* Refactor diskio's contents

- Change ff_disk_read_cb/write_cb into a std::function instead of a raw pointer
- Add const specifiers as needed

* Refactor DSi_NAND to manage the file system's mounted lifetime with RAII

* Split NANDMount into NANDMount and NANDImage

- NANDImage is used for information about the NAND that doesn't require decryption or filesystem access
- NANDMount is used to actually access the file system
- Both classes manage their respective resources (the NAND file handle and the NAND's mount) with RAII
- Also split the file loading into another function that I will remove in a later PR

* Make NANDMount immovable

* Remove NAND-loading code that I had sectioned off into a function

- Incomplete copypasta
- I must have gotten distracted

* Tidy up NANDImage's initialization

- Don't unmount the disk image if the constructor fails (that's NANDMount's job now)
- Only assign CurFile if the constructor succeeds

* Add some const-correctness

* Move DSi NAND initialization to the frontend

- The NANDImage is now installed via a unique_ptr in DSi

* Remove Platform::DSi_NANDPath

- Not Config::DSiNANDPath; that can still be configured as usual
- The core no longer needs to care

5 files changed, 92 insertions, 29 deletions

diff --git a/src/frontend/qt_sdl/Platform.cpp b/src/frontend/qt_sdl/Platform.cpp
index 0574d5d..7f6e1d5 100644
--- a/src/frontend/qt_sdl/Platform.cpp
+++ b/src/frontend/qt_sdl/Platform.cpp
@@ -250,8 +250,6 @@ std::string GetConfigString(ConfigEntry entry)
 {
     switch (entry)
     {
-    case DSi_NANDPath: return Config::DSiNANDPath;
-
     case DLDI_ImagePath: return Config::DLDISDPath;
     case DLDI_FolderPath: return Config::DLDIFolderPath;
 
diff --git a/src/frontend/qt_sdl/ROMManager.cpp b/src/frontend/qt_sdl/ROMManager.cpp
index 49f4c45..206332b 100644
--- a/src/frontend/qt_sdl/ROMManager.cpp
+++ b/src/frontend/qt_sdl/ROMManager.cpp
@@ -595,6 +595,10 @@ void Reset()
     LoadBIOSFiles();
 
     InstallFirmware();
+    if (Config::ConsoleType == 1)
+    {
+        InstallNAND(&DSi::ARM7iBIOS[0x8308]);
+    }
     NDS::Reset();
     SetBatteryLevels();
 
@@ -657,6 +661,9 @@ bool LoadBIOS()
     if (!InstallFirmware())
         return false;
 
+    if (Config::ConsoleType == 1 && !InstallNAND(&DSi::ARM7iBIOS[0x8308]))
+        return false;
+
     if (NDS::NeedsDirectBoot())
         return false;
 
@@ -948,6 +955,47 @@ void LoadUserSettingsFromConfig(SPI_Firmware::Firmware& firmware)
     firmware.UpdateChecksums();
 }
 
+static Platform::FileHandle* OpenNANDFile() noexcept
+{
+    std::string nandpath = Config::DSiNANDPath;
+    std::string instnand = nandpath + Platform::InstanceFileSuffix();
+
+    FileHandle* nandfile = Platform::OpenLocalFile(instnand, FileMode::ReadWriteExisting);
+    if ((!nandfile) && (Platform::InstanceID() > 0))
+    {
+        FileHandle* orig = Platform::OpenLocalFile(nandpath, FileMode::Read);
+        if (!orig)
+        {
+            Log(LogLevel::Error, "Failed to open DSi NAND\n");
+            return nullptr;
+        }
+
+        QFile::copy(QString::fromStdString(nandpath), QString::fromStdString(instnand));
+
+        nandfile = Platform::OpenLocalFile(instnand, FileMode::ReadWriteExisting);
+    }
+
+    return nandfile;
+}
+
+bool InstallNAND(const u8* es_keyY)
+{
+    Platform::FileHandle* nandfile = OpenNANDFile();
+    if (!nandfile)
+        return false;
+
+    if (auto nand = std::make_unique<DSi_NAND::NANDImage>(nandfile, es_keyY); *nand)
+    {
+        DSi::NANDImage = std::move(nand);
+        return true;
+    }
+    else
+    {
+        DSi::NANDImage = nullptr;
+        return false;
+    }
+}
+
 bool InstallFirmware()
 {
     using namespace SPI_Firmware;
@@ -1089,6 +1137,9 @@ bool LoadROM(QStringList filepath, bool reset)
         NDS::SetConsoleType(Config::ConsoleType);
         NDS::EjectCart();
         LoadBIOSFiles();
+        if (Config::ConsoleType == 1)
+            InstallNAND(&DSi::ARM7iBIOS[0x8308]);
+
         NDS::Reset();
         SetBatteryLevels();
     }
diff --git a/src/frontend/qt_sdl/ROMManager.h b/src/frontend/qt_sdl/ROMManager.h
index 5faef1a..2eeed0a 100644
--- a/src/frontend/qt_sdl/ROMManager.h
+++ b/src/frontend/qt_sdl/ROMManager.h
@@ -22,6 +22,7 @@
 #include "types.h"
 #include "SaveManager.h"
 #include "AREngine.h"
+#include "DSi_NAND.h"
 
 #include <string>
 #include <memory>
@@ -40,6 +41,7 @@ bool LoadBIOS();
 void ClearBackupState();
 
 bool InstallFirmware();
+bool InstallNAND(const u8* es_keyY);
 bool LoadROM(QStringList filepath, bool reset);
 void EjectCart();
 bool CartInserted();
diff --git a/src/frontend/qt_sdl/TitleManagerDialog.cpp b/src/frontend/qt_sdl/TitleManagerDialog.cpp
index d5147fc..84bd1ef 100644
--- a/src/frontend/qt_sdl/TitleManagerDialog.cpp
+++ b/src/frontend/qt_sdl/TitleManagerDialog.cpp
@@ -32,13 +32,13 @@
 
 using namespace Platform;
 
-bool TitleManagerDialog::NANDInited = false;
+std::unique_ptr<DSi_NAND::NANDImage> TitleManagerDialog::nand = nullptr;
 TitleManagerDialog* TitleManagerDialog::currentDlg = nullptr;
 
 extern std::string EmuDirectory;
 
 
-TitleManagerDialog::TitleManagerDialog(QWidget* parent) : QDialog(parent), ui(new Ui::TitleManagerDialog)
+TitleManagerDialog::TitleManagerDialog(QWidget* parent, DSi_NAND::NANDImage& image) : QDialog(parent), ui(new Ui::TitleManagerDialog), nandmount(image)
 {
     ui->setupUi(this);
     setAttribute(Qt::WA_DeleteOnClose);
@@ -47,7 +47,7 @@ TitleManagerDialog::TitleManagerDialog(QWidget* parent) : QDialog(parent), ui(ne
 
     const u32 category = 0x00030004;
     std::vector<u32> titlelist;
-    DSi_NAND::ListTitles(category, titlelist);
+    nandmount.ListTitles(category, titlelist);
 
     for (std::vector<u32>::iterator it = titlelist.begin(); it != titlelist.end(); it++)
     {
@@ -109,7 +109,7 @@ void TitleManagerDialog::createTitleItem(u32 category, u32 titleid)
     NDSHeader header;
     NDSBanner banner;
 
-    DSi_NAND::GetTitleInfo(category, titleid, version, &header, &banner);
+    nandmount.GetTitleInfo(category, titleid, version, &header, &banner);
 
     u32 icondata[32*32];
     ROMManager::ROMIcon(banner.Icon, banner.Palette, icondata);
@@ -137,7 +137,7 @@ void TitleManagerDialog::createTitleItem(u32 category, u32 titleid)
 
 bool TitleManagerDialog::openNAND()
 {
-    NANDInited = false;
+    nand = nullptr;
 
     FileHandle* bios7i = Platform::OpenLocalFile(Config::DSiBIOS7Path, FileMode::Read);
     if (!bios7i)
@@ -148,22 +148,25 @@ bool TitleManagerDialog::openNAND()
     FileRead(es_keyY, 16, 1, bios7i);
     CloseFile(bios7i);
 
-    if (!DSi_NAND::Init(es_keyY))
-    {
+    FileHandle* nandfile = Platform::OpenLocalFile(Config::DSiNANDPath, FileMode::ReadWriteExisting);
+    if (!nandfile)
+        return false;
+
+    nand = std::make_unique<DSi_NAND::NANDImage>(nandfile, es_keyY);
+    if (!*nand)
+    { // If loading and mounting the NAND image failed...
+        nand = nullptr;
         return false;
+        // NOTE: The NANDImage takes ownership of the FileHandle,
+        // so it will be closed even if the NANDImage constructor fails.
     }
 
-    NANDInited = true;
     return true;
 }
 
 void TitleManagerDialog::closeNAND()
 {
-    if (NANDInited)
-    {
-        DSi_NAND::DeInit();
-        NANDInited = false;
-    }
+    nand = nullptr;
 }
 
 void TitleManagerDialog::done(int r)
@@ -175,7 +178,7 @@ void TitleManagerDialog::done(int r)
 
 void TitleManagerDialog::on_btnImportTitle_clicked()
 {
-    TitleImportDialog* importdlg = new TitleImportDialog(this, importAppPath, &importTmdData, importReadOnly);
+    TitleImportDialog* importdlg = new TitleImportDialog(this, importAppPath, &importTmdData, importReadOnly, nandmount);
     importdlg->open();
     connect(importdlg, &TitleImportDialog::finished, this, &TitleManagerDialog::onImportTitleFinished);
 
@@ -190,14 +193,16 @@ void TitleManagerDialog::onImportTitleFinished(int res)
     titleid[0] = importTmdData.GetCategory();
     titleid[1] = importTmdData.GetID();
 
+    assert(nand != nullptr);
+    assert(*nand);
     // remove anything that might hinder the install
-    DSi_NAND::DeleteTitle(titleid[0], titleid[1]);
+    nandmount.DeleteTitle(titleid[0], titleid[1]);
 
-    bool importres = DSi_NAND::ImportTitle(importAppPath.toStdString().c_str(), importTmdData, importReadOnly);
+    bool importres = nandmount.ImportTitle(importAppPath.toStdString().c_str(), importTmdData, importReadOnly);
     if (!importres)
     {
         // remove a potential half-completed install
-        DSi_NAND::DeleteTitle(titleid[0], titleid[1]);
+        nandmount.DeleteTitle(titleid[0], titleid[1]);
 
         QMessageBox::critical(this,
                               "Import title - melonDS",
@@ -224,7 +229,7 @@ void TitleManagerDialog::on_btnDeleteTitle_clicked()
         return;
 
     u64 titleid = cur->data(Qt::UserRole).toULongLong();
-    DSi_NAND::DeleteTitle((u32)(titleid >> 32), (u32)titleid);
+    nandmount.DeleteTitle((u32)(titleid >> 32), (u32)titleid);
 
     delete cur;
 }
@@ -317,7 +322,7 @@ void TitleManagerDialog::onImportTitleData()
     }
 
     u64 titleid = cur->data(Qt::UserRole).toULongLong();
-    bool res = DSi_NAND::ImportTitleData((u32)(titleid >> 32), (u32)titleid, type, file.toStdString().c_str());
+    bool res = nandmount.ImportTitleData((u32)(titleid >> 32), (u32)titleid, type, file.toStdString().c_str());
     if (!res)
     {
         QMessageBox::critical(this,
@@ -370,7 +375,7 @@ void TitleManagerDialog::onExportTitleData()
     if (file.isEmpty()) return;
 
     u64 titleid = cur->data(Qt::UserRole).toULongLong();
-    bool res = DSi_NAND::ExportTitleData((u32)(titleid >> 32), (u32)titleid, type, file.toStdString().c_str());
+    bool res = nandmount.ExportTitleData((u32)(titleid >> 32), (u32)titleid, type, file.toStdString().c_str());
     if (!res)
     {
         QMessageBox::critical(this,
@@ -380,8 +385,8 @@ void TitleManagerDialog::onExportTitleData()
 }
 
 
-TitleImportDialog::TitleImportDialog(QWidget* parent, QString& apppath, const DSi_TMD::TitleMetadata* tmd, bool& readonly)
-: QDialog(parent), ui(new Ui::TitleImportDialog), appPath(apppath), tmdData(tmd), readOnly(readonly)
+TitleImportDialog::TitleImportDialog(QWidget* parent, QString& apppath, const DSi_TMD::TitleMetadata* tmd, bool& readonly, DSi_NAND::NANDMount& nandmount)
+: QDialog(parent), ui(new Ui::TitleImportDialog), appPath(apppath), tmdData(tmd), readOnly(readonly), nandmount(nandmount)
 {
     ui->setupUi(this);
     setAttribute(Qt::WA_DeleteOnClose);
@@ -455,7 +460,7 @@ void TitleImportDialog::accept()
         }
     }
 
-    if (DSi_NAND::TitleExists(titleid[1], titleid[0]))
+    if (nandmount.TitleExists(titleid[1], titleid[0]))
     {
         if (QMessageBox::question(this,
                                   "Import title - melonDS",
diff --git a/src/frontend/qt_sdl/TitleManagerDialog.h b/src/frontend/qt_sdl/TitleManagerDialog.h
index fc92fd8..5182e1d 100644
--- a/src/frontend/qt_sdl/TitleManagerDialog.h
+++ b/src/frontend/qt_sdl/TitleManagerDialog.h
@@ -19,6 +19,7 @@
 #ifndef TITLEMANAGERDIALOG_H
 #define TITLEMANAGERDIALOG_H
 
+#include <memory>
 #include <QDialog>
 #include <QMessageBox>
 #include <QListWidget>
@@ -30,6 +31,7 @@
 #include <QNetworkAccessManager>
 
 #include "DSi_TMD.h"
+#include "DSi_NAND.h"
 
 namespace Ui
 {
@@ -44,10 +46,10 @@ class TitleManagerDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit TitleManagerDialog(QWidget* parent);
+    explicit TitleManagerDialog(QWidget* parent, DSi_NAND::NANDImage& image);
     ~TitleManagerDialog();
 
-    static bool NANDInited;
+    static std::unique_ptr<DSi_NAND::NANDImage> nand;
     static bool openNAND();
     static void closeNAND();
 
@@ -68,7 +70,10 @@ public:
             return nullptr;
         }
 
-        currentDlg = new TitleManagerDialog(parent);
+        assert(nand != nullptr);
+        assert(*nand);
+
+        currentDlg = new TitleManagerDialog(parent, *nand);
         currentDlg->open();
         return currentDlg;
     }
@@ -89,6 +94,7 @@ private slots:
     void onExportTitleData();
 
 private:
+    DSi_NAND::NANDMount nandmount;
     Ui::TitleManagerDialog* ui;
 
     QString importAppPath;
@@ -106,7 +112,7 @@ class TitleImportDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit TitleImportDialog(QWidget* parent, QString& apppath, const DSi_TMD::TitleMetadata* tmd, bool& readonly);
+    explicit TitleImportDialog(QWidget* parent, QString& apppath, const DSi_TMD::TitleMetadata* tmd, bool& readonly, DSi_NAND::NANDMount& nand);
     ~TitleImportDialog();
 
 private slots:
@@ -119,6 +125,7 @@ private slots:
 
 private:
     Ui::TitleImportDialog* ui;
+    DSi_NAND::NANDMount& nandmount;
 
     QButtonGroup* grpTmdSource;