Storage

Every storage device is described by a StorageDevice (id, display name, mount prefix such as sd:/, volume label, whether it is removable, whether it is mounted automatically at startup, whether it is always shown in a device list, and optional capacity/free-space/block-size/read-only telemetry). The app enumerates devices, mounts them, and then builds paths with getMountPath() / getPath(); after that, all file access is ordinary POSIX I/O. getValidLoadDevices() and getValidSaveDevices() list which devices make sense as a load or save location on the current platform, and FindFirstMountedPath() picks the first mounted device out of a priority list.

Each device type has exactly one mount. A mount attempt returns MountResult::Success, DeviceNotFound, or MountFailed (something is present but can't be mounted, for example an unsupported format), and mountResultMessage() supplies a short string suitable for showing to the user.

Device	GameCube	Wii	Wii U
SD card	SD Gecko in slot A or B, SD2SP2 in serial port 2 (FAT)	SD slot (FAT)	SD slot, mounted natively by Cafe OS
USB storage	-	Up to 3 simultaneous drives (FAT), via IOS	Up to 3 simultaneous drives (FAT, exFAT, NTFS), via libmocha + libdvm
GC Loader	Mounted as a FAT device	-	-
DVD	Data DVD (ISO9660)	Data DVD (ISO9660)	-
Network share	SMB	SMB	SMB

Multiple USB drives. Wii and Wii U each expose three USB storage slots (DEVICE_USB, DEVICE_USB2, DEVICE_USB3). A newly attached drive takes the first free slot in attach order; slots are not tied to a physical port. On Wii this is handled by WiiUsbMulti, which opens each attached mass storage device through IOS independently and presents each one as its own disc interface. On Wii U, each slot is opened through libmocha's raw disc interface and mounted through libdvm, which recognizes FAT, exFAT, and NTFS. USB on Wii U requires the Mocha CFW component (available under Aroma); without it the USB slots are simply absent while the SD card and network share continue to work.

Hot-plug. Devices can be inserted and removed while the app runs. pollStorageDevices() is meant to be called about once a second from a background thread (the demo's device-checking thread does exactly this at low priority), and reports which mounted devices disappeared and whether the device list changed shape so the UI can refresh.

• Wii - SD, all three USB slots, and the DVD drive are checked each cycle.
• GameCube - SD Gecko slots A and B and SD2SP2 are checked each cycle with an EXI presence probe. The GC Loader and the DVD drive are only touched when the user mounts them.
• Wii U - USB attach/detach is detected by scanning the USB stack; a mounted USB volume is verified each cycle with a real, uncached sector read, so a drive that was pulled is noticed even if the filesystem cache could still answer from memory. A slot holding a device that won't mount gets a few quick retries and is then probed on a slow backoff schedule, which resets immediately when the USB stack reports a hardware change.

isDevicePresent() is a cheap, cached check that never mounts anything, so a UI can list only devices that are actually there (devices flagged alwaysListed, such as the network share, are shown regardless). On a mount failure or a read/write error, invalidateStorageDevice() marks a device to be re-mounted fresh on its next use.

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