Added support for Wii emulators (#59)

Cargo.toml

@@ -38,3 +38,4 @@ gcn = ["flags"]
 genesis = ["flags", "signature"]
 ps1 = ["flags", "signature"]
 ps2 = ["flags", "signature"]
+wii = ["flags"]

src/emulator/mod.rs

@@ -10,3 +10,5 @@ pub mod genesis;
 pub mod ps1;
 #[cfg(feature = "ps2")]
 pub mod ps2;
+#[cfg(feature = "wii")]
+pub mod wii;

src/emulator/wii/dolphin.rs

@@ -0,0 +1,46 @@
+use crate::{Address, Endian, FromEndian, MemoryRangeFlags, Process};
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub struct State;
+
+impl State {
+    pub fn find_ram(&self, game: &Process, endian: &mut Endian) -> Option<[Address; 2]> {
+        let mem_1 = game
+            .memory_ranges()
+            .find(|range| {
+                range
+                    .flags()
+                    .is_ok_and(|r| r.contains(MemoryRangeFlags::WRITE | MemoryRangeFlags::READ))
+                    && range.size().is_ok_and(|size| size == 0x2000000)
+                    && range.address().is_ok_and(|addr| {
+                        game.read::<[u32; 2]>(addr + 0x3118)
+                            .is_ok_and(|val| val.from_endian(Endian::Big) == [0x4000000; 2])
+                    })
+            })?
+            .address()
+            .ok()?;
+
+        let mem_2 = game
+            .memory_ranges()
+            .find(|range| {
+                range
+                    .flags()
+                    .is_ok_and(|r| r.contains(MemoryRangeFlags::WRITE | MemoryRangeFlags::READ))
+                    && range.size().is_ok_and(|size| size == 0x4000000)
+                    && range
+                        .address()
+                        .is_ok_and(|addr| addr > mem_1 && addr < mem_1 + 0x10000000)
+            })?
+            .address()
+            .ok()?;
+
+        *endian = Endian::Big;
+        Some([mem_1, mem_2])
+    }
+
+    pub fn keep_alive(&self, game: &Process, ram_base: &Option<[Address; 2]>) -> bool {
+        ram_base.is_some_and(|[mem1, mem2]| {
+            game.read::<u8>(mem1).is_ok() && game.read::<u8>(mem2).is_ok()
+        })
+    }
+}

src/emulator/wii/mod.rs

@@ -0,0 +1,213 @@
+//! Support for attaching to Nintendo Wii emulators.
+
+use crate::{Address, Endian, Error, FromEndian, Process};
+use bytemuck::CheckedBitPattern;
+
+mod dolphin;
+mod retroarch;
+
+/// A Nintendo Wii emulator that the auto splitter is attached to,
+/// for supporting Wii and WiiWare games.
+pub struct Emulator {
+    /// The attached emulator process
+    process: Process,
+    /// An enum stating which emulator is currently attached
+    state: State,
+    /// The memory address of the emulated RAM
+    ram_base: Option<[Address; 2]>, // [MEM1, MEM2]
+    /// The endianness used by the emulator process
+    endian: Endian,
+}
+
+impl Emulator {
+    /// Attaches to the emulator process
+    ///
+    /// Returns `Option<Emulator>` if successful, `None` otherwise.
+    ///
+    /// Supported emulators are:
+    /// - Dolphin
+    /// - Retroarch (using the `dolphin_libretro.dll` core)
+    pub fn attach() -> Option<Self> {
+        let (&state, process) = PROCESS_NAMES
+            .iter()
+            .find_map(|(name, state)| Some((state, Process::attach(name)?)))?;
+
+        Some(Self {
+            process,
+            state,
+            ram_base: None,      // [MEM1, MEM2]
+            endian: Endian::Big, // Endianness is usually Big in Wii emulators
+        })
+    }
+
+    /// Checks whether the emulator is still open. If it is not open anymore,
+    /// you should drop the emulator.
+    pub fn is_open(&self) -> bool {
+        self.process.is_open()
+    }
+
+    /// Calls the internal routines needed in order to find (and update, if
+    /// needed) the address of the emulated RAM.
+    ///
+    /// Returns true if successful, false otherwise.
+    pub fn update(&mut self) -> bool {
+        if self.ram_base.is_none() {
+            self.ram_base = match match &mut self.state {
+                State::Dolphin(x) => x.find_ram(&self.process, &mut self.endian),
+                State::Retroarch(x) => x.find_ram(&self.process, &mut self.endian),
+            } {
+                None => return false,
+                something => something,
+            };
+        }
+
+        let success = match &self.state {
+            State::Dolphin(x) => x.keep_alive(&self.process, &self.ram_base),
+            State::Retroarch(x) => x.keep_alive(&self.process, &self.ram_base),
+        };
+
+        if success {
+            true
+        } else {
+            self.ram_base = None;
+            false
+        }
+    }
+
+    /// Reads raw data from the emulated RAM ignoring all endianness settings.
+    /// The same call, performed on two different emulators, might return different
+    /// results due to the endianness used by the emulator.
+    ///
+    /// The address provided is meant to be the mapped address used on the original, big-endian system.
+    /// The call will automatically convert the address provided to its corresponding offset from
+    /// `MEM1` or `MEM2` and read the value.
+    ///
+    /// The provided memory address has to match a mapped memory address on the original Wii:
+    /// - Valid addresses for `MEM1` range from `0x80000000` to `0x817FFFFF`
+    /// - Valid addresses for `MEM2` range from `0x90000000` to `0x93FFFFFF`
+    ///
+    /// Any other invalid value will make this method immediately return `Err()`.
+    ///
+    /// This call is meant to be used by experienced users.
+    pub fn read_ignoring_endianness<T: CheckedBitPattern>(&self, address: u32) -> Result<T, Error> {
+        if address >= 0x80000000 && address <= 0x817FFFFF {
+            self.read_ignoring_endianness_from_mem_1(address)
+        } else if address >= 0x90000000 && address <= 0x93FFFFFF {
+            self.read_ignoring_endianness_from_mem_2(address)
+        } else {
+            Err(Error {})
+        }
+    }
+
+    /// Reads any value from the emulated RAM.
+    ///
+    /// The offset provided is meant to be the mapped address used on the original, big-endian system.
+    /// The call will automatically convert the address provided to its corresponding offset from
+    /// `MEM1` or `MEM2` and read the value, providing conversion from Big Endian to Little Endian.
+    ///
+    /// The provided memory address has to match a mapped memory address on the original Wii:
+    /// - Valid addresses for `MEM1` range from `0x80000000` to `0x817FFFFF`
+    /// - Valid addresses for `MEM2` range from `0x90000000` to `0x93FFFFFF`
+    ///
+    /// Any other invalid value will make this method immediately return `Err()`.
+    pub fn read<T: CheckedBitPattern + FromEndian>(&self, address: u32) -> Result<T, Error> {
+        Ok(self
+            .read_ignoring_endianness::<T>(address)?
+            .from_endian(self.endian))
+    }
+
+    /// Follows a path of pointers from the address given and reads a value of the type specified from
+    /// the process at the end of the pointer path.
+    ///
+    /// The end value is automatically converted to little endian if needed.
+    pub fn read_pointer_path<T: CheckedBitPattern + FromEndian>(
+        &self,
+        base_address: u32,
+        path: &[u32],
+    ) -> Result<T, Error> {
+        self.read(self.deref_offsets(base_address, path)?)
+    }
+
+    /// Follows a path of pointers from the address given and reads a value of the type specified from
+    /// the process at the end of the pointer path.
+    pub fn read_pointer_path_ignoring_endianness<T: CheckedBitPattern>(
+        &self,
+        base_address: u32,
+        path: &[u32],
+    ) -> Result<T, Error> {
+        self.read_ignoring_endianness(self.deref_offsets(base_address, path)?)
+    }
+
+    fn deref_offsets(&self, base_address: u32, path: &[u32]) -> Result<u32, Error> {
+        let mut address = base_address;
+        let (&last, path) = path.split_last().ok_or(Error {})?;
+        for &offset in path {
+            address = self.read::<u32>(address + offset)?;
+        }
+        Ok(address + last)
+    }
+
+    /// Reads raw data from the emulated RAM ignoring all endianness settings.
+    /// The same call, performed on two different emulators, might return different
+    /// results due to the endianness used by the emulator.
+    ///
+    /// The address provided is meant to be the mapped address used on the original, big-endian system.
+    /// The call will automatically convert the address provided to its corresponding offset from
+    /// `MEM1` or and read the value.
+    ///
+    /// The provided memory address has to match a mapped memory address on the original Wii.
+    /// Valid addresses for `MEM1` range from `0x80000000` to `0x817FFFFF`
+    ///
+    /// Any other invalid value will make this method immediately return `Err()`.
+    pub fn read_ignoring_endianness_from_mem_1<T: CheckedBitPattern>(
+        &self,
+        address: u32,
+    ) -> Result<T, Error> {
+        if address < 0x80000000 || address > 0x817FFFFF {
+            return Err(Error {});
+        }
+        let Some([mem1, _]) = self.ram_base else {
+            return Err(Error {});
+        };
+        let end_offset = address.checked_sub(0x80000000).unwrap_or(address);
+        self.process.read(mem1 + end_offset)
+    }
+
+    /// Reads raw data from the emulated RAM ignoring all endianness settings.
+    /// The same call, performed on two different emulators, might return different
+    /// results due to the endianness used by the emulator.
+    ///
+    /// The address provided is meant to be the mapped address used on the original, big-endian system.
+    /// The call will automatically convert the address provided to its corresponding offset from
+    /// `MEM2` or and read the value.
+    ///
+    /// The provided memory address has to match a mapped memory address on the original Wii.
+    /// Valid addresses for `MEM2` range from `0x90000000` to `0x93FFFFFF`
+    ///
+    /// Any other invalid value will make this method immediately return `Err()`.
+    pub fn read_ignoring_endianness_from_mem_2<T: CheckedBitPattern>(
+        &self,
+        address: u32,
+    ) -> Result<T, Error> {
+        if address < 0x90000000 || address > 0x93FFFFFF {
+            return Err(Error {});
+        }
+        let Some([_, mem2]) = self.ram_base else {
+            return Err(Error {});
+        };
+        let end_offset = address.checked_sub(0x90000000).unwrap_or(address);
+        self.process.read(mem2 + end_offset)
+    }
+}
+
+#[doc(hidden)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub enum State {
+    Dolphin(dolphin::State),
+    Retroarch(retroarch::State),
+}
+
+static PROCESS_NAMES: [(&str, State); 2] = [
+    ("Dolphin.exe", State::Dolphin(dolphin::State)),
+    ("retroarch.exe", State::Retroarch(retroarch::State::new())),
+];

src/emulator/wii/retroarch.rs

@@ -0,0 +1,45 @@
+use crate::{file_format::pe, Address, Endian, Process};
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub struct State {
+    core_base: Address,
+}
+
+impl State {
+    pub fn find_ram(&mut self, game: &Process, endian: &mut Endian) -> Option<[Address; 2]> {
+        const SUPPORTED_CORES: [&str; 1] = ["dolphin_libretro.dll"];
+
+        let main_module_address = super::PROCESS_NAMES
+            .iter()
+            .filter(|(_, state)| matches!(state, super::State::Retroarch(_)))
+            .find_map(|(name, _)| game.get_module_address(name).ok())?;
+
+        let is_64_bit =
+            pe::MachineType::read(game, main_module_address) == Some(pe::MachineType::X86_64);
+
+        if !is_64_bit {
+            // The Dolphin core, the only one available for retroarch, only supports 64-bit
+            return None;
+        }
+
+        self.core_base = SUPPORTED_CORES
+            .iter()
+            .find_map(|&m| game.get_module_address(m).ok())?;
+
+        *endian = Endian::Big;
+        super::dolphin::State::find_ram(&super::dolphin::State, game, endian)
+    }
+
+    pub fn keep_alive(&self, game: &Process, ram_base: &Option<[Address; 2]>) -> bool {
+        game.read::<u8>(self.core_base).is_ok()
+            && ram_base.is_some_and(|[mem1, mem2]| {
+                game.read::<u8>(mem1).is_ok() && game.read::<u8>(mem2).is_ok()
+            })
+    }
+
+    pub const fn new() -> Self {
+        Self {
+            core_base: Address::NULL,
+        }
+    }
+}