Refactor the core's handling of firmware and BIOS images to rely less on the file system (#1826)

* Introduce firmware-related structs

* Fix some indents

* Move the generated firmware identifier to a constant

* Document the WifiAccessPoint constructors

* Add some constants

* Remove a stray comment

* Implement Firmware::UserData

* Add Firmware::Mask

* Document Firmware::Buffer

* Add a Firmware constructor that uses a FileHandle

* Set the default username in UserData

* Update the UserData checksum

* Forgot to include Platform.h

* Remove some redundant assignments in the default Firmware constructor

* const-ify CRC16

* Replace the plain Firmware buffer with a Firmware object

- Remove some functions that were reimplemented in the Firmware constructors

* Fix some crashes due to undefined behavior

* Fix the user data initialization

- Initialize both user data objects to default
- Set both user data objects to the same touch screen calibration

* Follow the DS logic in determining which user data section is current

* Remove an unneeded include

* Remove another unneeded include

* Initialize FirmwareMask in Firmware::Firmware

* Use the DEFAULT_SSID constant

* Add SPI_Firmware::InstallFirmware and SPI_Firmware::RemoveFirmware

* Move a logging call to after the file is written

* Add a SaveManager for the firmware

* Touch up the SPI_Firmware::Firmware declaration

* Move all firmware loading and customization to the frontend

* Call Platform::WriteFirmware when it's time to write the firmware back to disk

* Fix some missing stuff

* Remove the Get* functions from SPI_Firmware in favor of GetFirmware()

* Implement SPI_Firmware::DeInit in terms of RemoveFirmware

* Add Firmware::UpdateChecksums

* Fix an incorrect length

* Update all checksums in the firmware after setting touch screen calibration data

* Use the Firmware object's Position methods

* Remove register fields from the Firmware object

* Install the firmware before seeing if direct boot is necessary

* Install the firmware before calling NDS::Reset in LoadROM

* Slight cleanup in ROMManager

* Fix the default access point name

* Shorten the various getters in Firmware

* Add qualifiers for certain uses of firmware types

- GCC can get picky if -fpermissive isn't defined

* Add an InstallFirmware overload that takes a unique_ptr

* Log when firmware is added or removed

* Don't clear the firmware in SPI_Firmware::Init

- The original code didn't, it just set the pointer to nullptr

* Fix a typo

* Write back the full firmware if it's not generated

* Move the FreeBIOS to an external file

* Load wfcsettings.bin into the correct part of the generated firmware blob

* Load BIOS files in the frontend, not in the core

* Fix logging the firmware ID

* Add some utility functions

* Mark Firmware's constructors as explicit

* Remove obsolete ConfigEntry values

* Include <locale> explicitly in ROMManager

* Fix up some includes

* Add Firmware::IsBootable()

* Add a newline to a log entry

- Whoops

* Log the number of bytes written out in SaveManager

* Mark FirmwareHeader's constructor as explicit

* Clean up GenerateDefaultFirmware and LoadFirmwareFromFile

- Now they return a pair instead of two by-ref values

* Refactor SaveManager a little bit

- Manage its buffers as unique_ptrs to mitigate leaks
- Reallocate the internal buffer if SetPath is asked to reload the file (and the new length is different)

* Remove some stray parens

* Fix some firmware-related bugs I introduced

- Firmware settings are now properly saved to disk (beforehand I misunderstood when the firmware blob was written)
- Firmware is no longer overwritten by contents of wfcsettings.bin

* Slight cleanup

src/frontend/qt_sdl/Platform.cpp

@@ -39,6 +39,7 @@
 #include "LAN_PCap.h"
 #include "LocalMP.h"
 #include "OSD.h"
+#include "SPI_Firmware.h"
 
 #ifdef __WIN32__
 #define fseek _fseeki64
@@ -249,13 +250,6 @@ std::string GetConfigString(ConfigEntry entry)
 {
     switch (entry)
     {
-    case BIOS9Path: return Config::BIOS9Path;
-    case BIOS7Path: return Config::BIOS7Path;
-    case FirmwarePath: return Config::FirmwarePath;
-
-    case DSi_BIOS9Path: return Config::DSiBIOS9Path;
-    case DSi_BIOS7Path: return Config::DSiBIOS7Path;
-    case DSi_FirmwarePath: return Config::DSiFirmwarePath;
     case DSi_NANDPath: return Config::DSiNANDPath;
 
     case DLDI_ImagePath: return Config::DLDISDPath;
@@ -584,7 +578,36 @@ void WriteGBASave(const u8* savedata, u32 savelen, u32 writeoffset, u32 writelen
         ROMManager::GBASave->RequestFlush(savedata, savelen, writeoffset, writelen);
 }
 
+void WriteFirmware(const SPI_Firmware::Firmware& firmware, u32 writeoffset, u32 writelen)
+{
+    if (!ROMManager::FirmwareSave)
+        return;
 
+    if (firmware.Header().Identifier != SPI_Firmware::GENERATED_FIRMWARE_IDENTIFIER)
+    { // If this is not the default built-in firmware...
+        // ...then write the whole thing back.
+        ROMManager::FirmwareSave->RequestFlush(firmware.Buffer(), firmware.Length(), writeoffset, writelen);
+    }
+    else
+    {
+        u32 eapstart = firmware.ExtendedAccessPointOffset();
+        u32 eapend = eapstart + sizeof(firmware.ExtendedAccessPoints());
+
+        u32 apstart = firmware.WifiAccessPointOffset();
+        u32 apend = apstart + sizeof(firmware.AccessPoints());
+
+        // assert that the extended access points come just before the regular ones
+        assert(eapend == apstart);
+
+        if (eapstart <= writeoffset && writeoffset < apend)
+        { // If we're writing to the access points...
+            const u8* buffer = firmware.ExtendedAccessPointPosition();
+            u32 length = sizeof(firmware.ExtendedAccessPoints()) + sizeof(firmware.AccessPoints());
+            ROMManager::FirmwareSave->RequestFlush(buffer, length, writeoffset - eapstart, writelen);
+        }
+    }
+
+}
 
 bool MP_Init()
 {