swdc: first segatools added

Package.mk

@@ -88,6 +88,21 @@ $(BUILD_DIR_ZIP)/idac.zip:
 	$(V)strip $(BUILD_DIR_ZIP)/idac/*.{exe,dll}
 	$(V)cd $(BUILD_DIR_ZIP)/idac ; zip -r ../idac.zip *
 
+$(BUILD_DIR_ZIP)/swdc.zip:
+	$(V)echo ... $@
+	$(V)mkdir -p $(BUILD_DIR_ZIP)/swdc
+	$(V)mkdir -p $(BUILD_DIR_ZIP)/swdc/DEVICE
+	$(V)cp $(BUILD_DIR_64)/subprojects/capnhook/inject/inject.exe \
+		$(BUILD_DIR_64)/swdchook/swdchook.dll \
+		$(DIST_DIR)/swdc/segatools.ini \
+		$(DIST_DIR)/swdc/start.bat \
+    	$(BUILD_DIR_ZIP)/swdc
+	$(V)cp pki/billing.pub \
+		pki/ca.crt \
+    	$(BUILD_DIR_ZIP)/swdc/DEVICE
+	$(V)strip $(BUILD_DIR_ZIP)/swdc/*.{exe,dll}
+	$(V)cd $(BUILD_DIR_ZIP)/swdc ; zip -r ../swdc.zip *
+
 $(BUILD_DIR_ZIP)/mercury.zip:
 	$(V)echo ... $@
 	$(V)mkdir -p $(BUILD_DIR_ZIP)/mercury
@@ -135,6 +150,7 @@ $(BUILD_DIR_ZIP)/segatools.zip: \
 		$(BUILD_DIR_ZIP)/doc.zip \
 		$(BUILD_DIR_ZIP)/idz.zip \
 		$(BUILD_DIR_ZIP)/idac.zip \
+		$(BUILD_DIR_ZIP)/swdc.zip \
 		$(BUILD_DIR_ZIP)/mercury.zip \
 		$(BUILD_DIR_ZIP)/mu3.zip \
 		CHANGELOG.md \

README.md

@@ -1,6 +1,6 @@
 # Segatools
 
-Version: `v005`
+Version: `2023-07-14`
 
 Loaders and hardware emulators for SEGA games that run on the Nu and ALLS platforms.
 
@@ -14,6 +14,9 @@ Loaders and hardware emulators for SEGA games that run on the Nu and ALLS platfo
   * [Chunithm Crystal (Plus)](doc/chunihook.md)
 * Initial D
   * [Initial D Arcade Stage Zero](doc/idzhook.md)
+  * Initial D The Arcade
+* SEGA World Drivers Championship
+  * SEGA World Drivers Championship 2019
 * Wacca
   * Wacca Lilly R (WIP)
 

dist/swdc/segatools.ini

@@ -0,0 +1,99 @@
+[vfs]
+; Insert the path to the game AMFS directory here (contains ICF1 and ICF2)
+amfs=
+; Insert the path to the game Option directory here (contains OPxx directories)
+option=
+; Create an empty directory somewhere and insert the path here.
+; This directory may be shared between multiple SEGA games.
+; NOTE: This has nothing to do with Windows %APPDATA%.
+appdata=
+
+[aime]
+; Controls emulation of the Aime card reader assembly.
+enable=1
+aimePath=DEVICE\aime.txt
+felicaGen=0
+
+[dns]
+; Insert the hostname or IP address of the server you wish to use here.
+; Note that 127.0.0.1, localhost etc are specifically rejected.
+default=127.0.0.1
+
+[netenv]
+; Simulate an ideal LAN environment. This may interfere with head-to-head play.
+; SEGA games are somewhat picky about their LAN environment, so leaving this
+; setting enabled is recommended.
+enable=1
+
+[keychip]
+; The /24 LAN subnet that the emulated keychip will tell the game to expect.
+; You must set this to your LAN's IP subnet, and that subnet must start with 192.168.
+subnet=192.168.100.0
+
+[aimeio]
+; To use a custom card reader IO DLL enter its path here.
+; Leave empty if you want to use Segatools built-in keyboard input.
+path=
+
+[swdcio]
+; To use a custom SEGA World Drivers Championship DLL enter its path here.
+; Leave empty if you want to use Segatools built-in gamepad/wheel input.
+path=
+
+[io4]
+; Test button virtual-key code. Default is the 1 key.
+test=0x31
+; Service button virtual-key code. Default is the 2 key.
+service=0x32
+; Keyboard button to increment coin counter. Default is the 3 key.
+coin=0x33
+; Input API selection for IO4 input emulator.
+; Set "xinput" to use a gamepad and "dinput" to use a steering wheel.
+mode=xinput
+; Use the left thumbstick for steering instead of both on XInput Controllers.
+; Not recommended as it will not give you the precision needed for this game
+singleStickSteering=1
+; Adjust scaling for steering wheel input.
+;
+; This setting scales the steering wheel input so that the maximum positive
+; and minimum negative steering inputs reported in the operator menu's input
+; test screen do not exceed the value below. The maximum possible value is 128,
+; and the value that matches the input range of a real cabinet is 97.
+;
+; NOTE: This is not the same thing as DirectInput steering wheel movement
+; range! Segatools cannot control the maximum angle of your physical steering
+; wheel controller, this setting is vendor-specific and can only be adjusted
+; in the Control Panel.
+restrict=97
+
+[dinput]
+; Name of the DirectInput wheel to use (or any text that occurs in its name)
+; Example: TMX
+;
+; If this is left blank then the first DirectInput device will be used.
+deviceName=
+; Pedal mappings. Valid axis names are:
+;
+; X, Y, Z, RX, RY, RZ, U, V
+;
+; (U and V are old names for Slider 1 and Slider 2).
+; The examples below are valid for a Thrustmaster TMX.
+brakeAxis=RZ
+accelAxis=Y
+; DirectInput button numbers to map to menu inputs. Note that buttons are
+; numbered from 1; some software numbers buttons from 0.
+start=3
+viewChg=10
+; Button mappings for the steering wheel paddles. Note shiftDn is the
+; left paddle and shiftUp is the right paddle.
+shiftDn=1
+shiftUp=2
+; Button mappings for the steering wheel buttons.
+wheelGreen=4
+wheelRed=5
+wheelBlue=6
+wheelYellow=7
+; Invert the accelerator and or brake axis
+; (Needed when using DirectInput for the Dualshock 4 for example)
+reverseAccelAxis=0
+reverseBrakeAxis=0

dist/swdc/start.bat

@@ -0,0 +1,29 @@
+@echo off
+
+pushd %~dp0
+
+REM set the APP_DIR to the Y drive
+set APP_DIR=Y:\SWDC
+
+REM create the APP_DIR if it doesn't exist and redirect it to the TEMP folder
+if not exist "%APP_DIR%" (
+    subst Y: %TEMP%
+    REM timeout /t 1
+    if not exist "%APP_DIR%" (
+        mkdir "%APP_DIR%"
+    )
+)
+
+echo Mounted the Y:\ drive to the %TEMP%\SWDC folder
+
+REM start /min inject -d -k swdchook.dll amdaemon.exe -f -c config.json config_LanClient.json config_MiniCabinet.json
+start /min inject -d -k swdchook.dll amdaemon.exe -f -c config.json config_LanServer.json config_MiniCabinet.json
+inject -d -k swdchook.dll ..\Todoroki\Binaries\Win64\Todoroki-Win64-Shipping.exe -launch=MiniCabinet -ABSLOG="..\..\..\..\..\Userdata\GameProject.log" -UserDir="..\..\..\Userdata" -NotInstalled -UNATTENDED
+taskkill /f /im amdaemon.exe > nul 2>&1
+
+REM unmount the APP_DIR
+subst Y: /d > nul 2>&1
+
+echo.
+echo Game processes have terminated
+pause

meson.build

@@ -59,6 +59,7 @@ subdir('divaio')
 subdir('carolio')
 subdir('idzio')
 subdir('idacio')
+subdir('swdcio')
 subdir('mu3io')
 subdir('mercuryio')
 subdir('cxbio')
@@ -68,6 +69,7 @@ subdir('divahook')
 subdir('carolhook')
 subdir('idzhook')
 subdir('idachook')
+subdir('swdchook')
 subdir('minihook')
 subdir('mu3hook')
 subdir('mercuryhook')

swdchook/config.c

@@ -0,0 +1,53 @@
+#include <assert.h>
+#include <stddef.h>
+
+#include "board/config.h"
+#include "board/sg-reader.h"
+
+#include "hooklib/config.h"
+#include "hooklib/dvd.h"
+
+#include "swdchook/config.h"
+#include "swdchook/swdc-dll.h"
+
+#include "platform/config.h"
+#include "platform/platform.h"
+
+void swdc_dll_config_load(
+        struct swdc_dll_config *cfg,
+        const wchar_t *filename)
+{
+    assert(cfg != NULL);
+    assert(filename != NULL);
+
+    GetPrivateProfileStringW(
+            L"swdcio",
+            L"path",
+            L"",
+            cfg->path,
+            _countof(cfg->path),
+            filename);
+}
+
+void swdc_hook_config_load(
+        struct swdc_hook_config *cfg,
+        const wchar_t *filename)
+{
+    assert(cfg != NULL);
+    assert(filename != NULL);
+
+    platform_config_load(&cfg->platform, filename);
+    aime_config_load(&cfg->aime, filename);
+    swdc_dll_config_load(&cfg->dll, filename);
+    zinput_config_load(&cfg->zinput, filename);
+    dvd_config_load(&cfg->dvd, filename);
+    io4_config_load(&cfg->io4, filename);
+}
+
+void zinput_config_load(struct zinput_config *cfg, const wchar_t *filename)
+{
+    assert(cfg != NULL);
+    assert(filename != NULL);
+
+    cfg->enable = GetPrivateProfileIntW(L"zinput", L"enable", 1, filename);
+}

swdchook/config.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stddef.h>
+
+#include "board/config.h"
+
+#include "hooklib/dvd.h"
+
+#include "swdchook/swdc-dll.h"
+#include "swdchook/zinput.h"
+
+#include "platform/platform.h"
+
+struct swdc_hook_config {
+    struct platform_config platform;
+    struct aime_config aime;
+    struct dvd_config dvd;
+    struct io4_config io4;
+    struct swdc_dll_config dll;
+    struct zinput_config zinput;
+};
+
+void swdc_dll_config_load(
+        struct swdc_dll_config *cfg,
+        const wchar_t *filename);
+
+void swdc_hook_config_load(
+        struct swdc_hook_config *cfg,
+        const wchar_t *filename);
+
+void zinput_config_load(struct zinput_config *cfg, const wchar_t *filename);

swdchook/dllmain.c

@@ -0,0 +1,112 @@
+#include <windows.h>
+#include <shlwapi.h>
+
+#include <stdlib.h>
+
+#include "board/sg-reader.h"
+#include "board/io4.h"
+#include "board/vfd.h"
+
+#include "hook/process.h"
+
+#include "hooklib/dvd.h"
+#include "hooklib/serial.h"
+#include "hooklib/spike.h"
+
+#include "swdchook/config.h"
+#include "swdchook/swdc-dll.h"
+#include "swdchook/io4.h"
+#include "swdchook/zinput.h"
+
+#include "platform/platform.h"
+
+#include "util/dprintf.h"
+
+static HMODULE swdc_hook_mod;
+static process_entry_t swdc_startup;
+static struct swdc_hook_config swdc_hook_cfg;
+
+static DWORD CALLBACK swdc_pre_startup(void)
+{
+    HRESULT hr;
+
+    dprintf("--- Begin swdc_pre_startup ---\n");
+
+    /* Config load */
+
+    swdc_hook_config_load(&swdc_hook_cfg, L".\\segatools.ini");
+
+    /* Hook Win32 APIs */
+
+    serial_hook_init();
+    zinput_hook_init(&swdc_hook_cfg.zinput);
+    dvd_hook_init(&swdc_hook_cfg.dvd, swdc_hook_mod);
+
+    /* Initialize emulation hooks */
+
+    hr = platform_hook_init(
+            &swdc_hook_cfg.platform,
+            "SDDS",
+            "ACA4",
+            swdc_hook_mod);
+
+    if (FAILED(hr)) {
+        goto fail;
+    }
+
+    hr = sg_reader_hook_init(&swdc_hook_cfg.aime, 3, swdc_hook_mod);
+
+    if (FAILED(hr)) {
+        goto fail;
+    }
+
+    hr = vfd_hook_init(4);
+
+    if (FAILED(hr)) {
+        return hr;
+    }
+
+    hr = swdc_dll_init(&swdc_hook_cfg.dll, swdc_hook_mod);
+
+    if (FAILED(hr)) {
+        goto fail;
+    }
+
+    hr = swdc_io4_hook_init(&swdc_hook_cfg.io4);
+
+    if (FAILED(hr)) {
+        goto fail;
+    }
+
+    /* Initialize debug helpers */
+
+    spike_hook_init(L".\\segatools.ini");
+
+    dprintf("---  End  swdc_pre_startup ---\n");
+
+    /* Jump to EXE start address */
+
+    return swdc_startup();
+
+fail:
+    ExitProcess(EXIT_FAILURE);
+}
+
+BOOL WINAPI DllMain(HMODULE mod, DWORD cause, void *ctx)
+{
+    HRESULT hr;
+
+    if (cause != DLL_PROCESS_ATTACH) {
+        return TRUE;
+    }
+
+    swdc_hook_mod = mod;
+
+    hr = process_hijack_startup(swdc_pre_startup, &swdc_startup);
+
+    if (!SUCCEEDED(hr)) {
+        dprintf("Failed to hijack process startup: %x\n", (int) hr);
+    }
+
+    return SUCCEEDED(hr);
+}

swdchook/io4.c

@@ -0,0 +1,137 @@
+#include <windows.h>
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "board/io4.h"
+
+#include "swdchook/swdc-dll.h"
+
+#include "util/dprintf.h"
+
+static HRESULT swdc_io4_poll(void *ctx, struct io4_state *state);
+static uint16_t coins;
+
+static const struct io4_ops swdc_io4_ops = {
+    .poll = swdc_io4_poll,
+};
+
+HRESULT swdc_io4_hook_init(const struct io4_config *cfg)
+{
+    HRESULT hr;
+
+    assert(swdc_dll.init != NULL);
+
+    hr = io4_hook_init(cfg, &swdc_io4_ops, NULL);
+
+    if (FAILED(hr)) {
+        return hr;
+    }
+
+    return swdc_dll.init();
+}
+
+static HRESULT swdc_io4_poll(void *ctx, struct io4_state *state)
+{
+    uint8_t opbtn;
+    uint16_t gamebtn;
+    struct swdc_io_analog_state analog_state;
+    HRESULT hr;
+
+    assert(swdc_dll.poll != NULL);
+    assert(swdc_dll.get_opbtns != NULL);
+    assert(swdc_dll.get_gamebtns != NULL);
+    assert(swdc_dll.get_analogs != NULL);
+
+    memset(state, 0, sizeof(*state));
+    memset(&analog_state, 0, sizeof(analog_state));
+
+    hr = swdc_dll.poll();
+
+    if (FAILED(hr)) {
+        return hr;
+    }
+
+    opbtn = 0;
+    gamebtn = 0;
+
+    swdc_dll.get_opbtns(&opbtn);
+    swdc_dll.get_gamebtns(&gamebtn);
+    swdc_dll.get_analogs(&analog_state);
+
+    if (opbtn & SWDC_IO_OPBTN_TEST) {
+        state->buttons[0] |= IO4_BUTTON_TEST;
+    }
+
+    if (opbtn & SWDC_IO_OPBTN_SERVICE) {
+        state->buttons[0] |= IO4_BUTTON_SERVICE;
+    }
+
+    if (opbtn & SWDC_IO_OPBTN_COIN) {
+        coins++;
+    }
+    state->chutes[0] = coins << 8;
+
+    /* Update Cabinet buttons */
+
+    if (gamebtn & SWDC_IO_GAMEBTN_START) {
+        state->buttons[0] |= 1 << 7;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_VIEW_CHANGE) {
+        state->buttons[0] |= 1 << 1;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_UP) {
+        state->buttons[0] |= 1 << 5;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_DOWN) {
+        state->buttons[0] |= 1 << 4;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_LEFT) {
+        state->buttons[0] |= 1 << 3;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_RIGHT) {
+        state->buttons[0] |= 1 << 2;
+    }
+
+    /* Update steering wheel buttons */
+
+    if (gamebtn & SWDC_IO_GAMEBTN_STEERING_BLUE) {
+        state->buttons[1] |= 1 << 15;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_STEERING_GREEN) {
+        state->buttons[1] |= 1 << 14;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_STEERING_RED) {
+        state->buttons[1] |= 1 << 13;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_STEERING_YELLOW) {
+        state->buttons[1] |= 1 << 12;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_STEERING_PADDLE_LEFT) {
+        state->buttons[1] |= 1 << 1;
+    }
+
+    if (gamebtn & SWDC_IO_GAMEBTN_STEERING_PADDLE_RIGHT) {
+        state->buttons[1] |= 1 << 0;
+    }
+
+    /* Steering wheel increases left-to-right.
+
+       Use 0x8000 as the center point. */
+
+    state->adcs[0] = 0x8000 + analog_state.wheel;
+    state->adcs[1] = analog_state.accel;
+    state->adcs[2] = analog_state.brake;
+
+    return S_OK;
+}

swdchook/io4.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <windows.h>
+
+#include "board/io4.h"
+
+HRESULT swdc_io4_hook_init(const struct io4_config *cfg);

swdchook/meson.build

@@ -0,0 +1,32 @@
+shared_library(
+    'swdchook',
+    name_prefix : '',
+    include_directories : inc,
+    implicit_include_directories : false,
+    vs_module_defs : 'swdchook.def',
+    c_pch : '../precompiled.h',
+    dependencies : [
+        capnhook.get_variable('hook_dep'),
+        capnhook.get_variable('hooklib_dep'),
+        xinput_lib,
+    ],
+    link_with : [
+        aimeio_lib,
+        board_lib,
+        hooklib_lib,
+        swdcio_lib,
+        platform_lib,
+        util_lib,
+    ],
+    sources : [
+        'config.c',
+        'config.h',
+        'dllmain.c',
+        'swdc-dll.c',
+        'swdc-dll.h',
+        'io4.c',
+        'io4.h',
+        'zinput.c',
+        'zinput.h',
+    ],
+)

swdchook/swdc-dll.c

@@ -0,0 +1,112 @@
+#include <windows.h>
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "swdchook/swdc-dll.h"
+
+#include "util/dll-bind.h"
+#include "util/dprintf.h"
+
+const struct dll_bind_sym swdc_dll_syms[] = {
+    {
+        .sym = "swdc_io_init",
+        .off = offsetof(struct swdc_dll, init),
+    }, {
+        .sym = "swdc_io_poll",
+        .off = offsetof(struct swdc_dll, poll),
+    }, {
+        .sym = "swdc_io_get_opbtns",
+        .off = offsetof(struct swdc_dll, get_opbtns),
+    }, {
+        .sym = "swdc_io_get_gamebtns",
+        .off = offsetof(struct swdc_dll, get_gamebtns),
+    }, {
+        .sym = "swdc_io_get_analogs",
+        .off = offsetof(struct swdc_dll, get_analogs),
+    }
+};
+
+struct swdc_dll swdc_dll;
+
+// Copypasta DLL binding and diagnostic message boilerplate.
+// Not much of this lends itself to being easily factored out. Also there
+// will be a lot of API-specific branching code here eventually as new API
+// versions get defined, so even though these functions all look the same
+// now this won't remain the case forever.
+
+HRESULT swdc_dll_init(const struct swdc_dll_config *cfg, HINSTANCE self)
+{
+    uint16_t (*get_api_version)(void);
+    const struct dll_bind_sym *sym;
+    HINSTANCE owned;
+    HINSTANCE src;
+    HRESULT hr;
+
+    assert(cfg != NULL);
+    assert(self != NULL);
+
+    if (cfg->path[0] != L'\0') {
+        owned = LoadLibraryW(cfg->path);
+
+        if (owned == NULL) {
+            hr = HRESULT_FROM_WIN32(GetLastError());
+            dprintf("SWDC IO: Failed to load IO DLL: %lx: %S\n",
+                    hr,
+                    cfg->path);
+
+            goto end;
+        }
+
+        dprintf("SWDC IO: Using custom IO DLL: %S\n", cfg->path);
+        src = owned;
+    } else {
+        owned = NULL;
+        src = self;
+    }
+
+    get_api_version = (void *) GetProcAddress(src, "swdc_io_get_api_version");
+
+    if (get_api_version != NULL) {
+        swdc_dll.api_version = get_api_version();
+    } else {
+        swdc_dll.api_version = 0x0100;
+        dprintf("Custom IO DLL does not expose swdc_io_get_api_version, "
+                "assuming API version 1.0.\n"
+                "Please ask the developer to update their DLL.\n");
+    }
+
+    if (swdc_dll.api_version >= 0x0200) {
+        hr = E_NOTIMPL;
+        dprintf("SWDC IO: Custom IO DLL implements an unsupported "
+                "API version (%#04x). Please update Segatools.\n",
+                swdc_dll.api_version);
+
+        goto end;
+    }
+
+    sym = swdc_dll_syms;
+    hr = dll_bind(&swdc_dll, src, &sym, _countof(swdc_dll_syms));
+
+    if (FAILED(hr)) {
+        if (src != self) {
+            dprintf("SWDC IO: Custom IO DLL does not provide function "
+                    "\"%s\". Please contact your IO DLL's developer for "
+                    "further assistance.\n",
+                    sym->sym);
+
+            goto end;
+        } else {
+            dprintf("Internal error: could not reflect \"%s\"\n", sym->sym);
+        }
+    }
+
+    owned = NULL;
+
+end:
+    if (owned != NULL) {
+        FreeLibrary(owned);
+    }
+
+    return hr;
+}

swdchook/swdc-dll.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <windows.h>
+
+#include "swdcio/swdcio.h"
+
+struct swdc_dll {
+    uint16_t api_version;
+    HRESULT (*init)(void);
+    HRESULT (*poll)(void);
+    void (*get_opbtns)(uint8_t *opbtn);
+    void (*get_gamebtns)(uint16_t *gamebtn);
+    void (*get_analogs)(struct swdc_io_analog_state *out);
+};
+
+struct swdc_dll_config {
+    wchar_t path[MAX_PATH];
+};
+
+extern struct swdc_dll swdc_dll;
+
+HRESULT swdc_dll_init(const struct swdc_dll_config *cfg, HINSTANCE self);

swdchook/swdchook.def

@@ -0,0 +1,19 @@
+LIBRARY swdchook
+
+EXPORTS
+    aime_io_get_api_version
+    aime_io_init
+    aime_io_led_set_color
+    aime_io_nfc_get_aime_id
+    aime_io_nfc_get_felica_id
+    aime_io_nfc_poll
+    amDllVideoClose @2
+    amDllVideoGetVBiosVersion @4
+    amDllVideoOpen @1
+    amDllVideoSetResolution @3
+    swdc_io_get_api_version
+    swdc_io_init
+    swdc_io_poll
+    swdc_io_get_opbtns
+    swdc_io_get_gamebtns
+    swdc_io_get_analogs

swdchook/zinput.c

@@ -0,0 +1,186 @@
+#include <windows.h>
+#include <dinput.h>
+
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "swdchook/config.h"
+#include "swdchook/zinput.h"
+
+#include "hook/table.h"
+
+#include "util/dprintf.h"
+
+HRESULT WINAPI hook_DirectInput8Create(
+         HINSTANCE hinst,
+         DWORD dwVersion,
+         REFIID riidltf,
+         LPVOID *ppvOut,
+         LPUNKNOWN punkOuter);
+
+static unsigned long WINAPI hook_AddRef(IUnknown *self);
+
+static unsigned long WINAPI hook_Release(IUnknown *self);
+
+static HRESULT WINAPI hook_CreateDevice(
+        IDirectInput8W *self,
+        REFGUID rguid,
+        LPDIRECTINPUTDEVICE8W * lplpDirectInputDevice,
+        LPUNKNOWN pUnkOuter);
+
+static HRESULT WINAPI hook_EnumDevices(
+        IDirectInput8W *self,
+        DWORD dwDevType,
+        LPDIENUMDEVICESCALLBACKW lpCallback,
+        LPVOID pvRef,
+        DWORD dwFlags);
+
+static HRESULT WINAPI hook_SetDataFormat(
+        IDirectInputDevice8W *self,
+        LPCDIDATAFORMAT lpdf);
+
+static HRESULT WINAPI hook_SetCooperativeLevel(
+        IDirectInputDevice8W *self,
+        HWND hwnd,
+        DWORD flags);
+
+static HRESULT WINAPI hook_Acquire(IDirectInputDevice8W *self);
+
+static HRESULT WINAPI hook_Unacquire(IDirectInputDevice8W *self);
+
+static HRESULT WINAPI hook_GetDeviceState(
+        IDirectInputDevice8W *self,
+        DWORD cbData,
+        LPVOID lpvData);
+
+static const IDirectInput8WVtbl api_vtbl = {
+    .AddRef             = (void *) hook_AddRef,
+    .Release            = (void *) hook_Release,
+    .CreateDevice       = hook_CreateDevice,
+    .EnumDevices        = hook_EnumDevices,
+};
+
+static const IDirectInput8W api = { (void *) &api_vtbl };
+
+static const IDirectInputDevice8WVtbl dev_vtbl = {
+    .AddRef             = (void *) hook_AddRef,
+    .Release            = (void *) hook_Release,
+    .SetDataFormat      = hook_SetDataFormat,
+    .SetCooperativeLevel= hook_SetCooperativeLevel,
+    .Acquire            = hook_Acquire,
+    .Unacquire          = hook_Unacquire,
+    .GetDeviceState     = hook_GetDeviceState,
+};
+
+static const IDirectInputDevice8W dev = { (void *) &dev_vtbl };
+
+static const struct hook_symbol zinput_hook_syms[] = {
+    {
+        .name   = "DirectInput8Create",
+        .patch  = hook_DirectInput8Create,
+    }
+};
+
+HRESULT zinput_hook_init(struct zinput_config *cfg)
+{
+    assert(cfg != NULL);
+
+    if (!cfg->enable) {
+        return S_FALSE;
+    }
+
+    hook_table_apply(
+            NULL,
+            "dinput8.dll",
+            zinput_hook_syms,
+            _countof(zinput_hook_syms));
+
+    return S_OK;
+}
+
+HRESULT WINAPI hook_DirectInput8Create(
+         HINSTANCE hinst,
+         DWORD dwVersion,
+         REFIID riidltf,
+         LPVOID *ppvOut,
+         LPUNKNOWN punkOuter)
+{
+    dprintf("ZInput: Blocking built-in DirectInput support\n");
+    *ppvOut = (void *) &api;
+
+    return S_OK;
+}
+
+static unsigned long WINAPI hook_AddRef(IUnknown *self)
+{
+    return 1;
+}
+
+static unsigned long WINAPI hook_Release(IUnknown *self)
+{
+    return 1;
+}
+
+static HRESULT WINAPI hook_CreateDevice(
+        IDirectInput8W *self,
+        REFGUID rguid,
+        LPDIRECTINPUTDEVICE8W *lplpDirectInputDevice,
+        LPUNKNOWN pUnkOuter)
+{
+    dprintf("ZInput: %s\n", __func__);
+    *lplpDirectInputDevice = (void *) &dev;
+
+    return S_OK;
+}
+
+static HRESULT WINAPI hook_EnumDevices(
+        IDirectInput8W *self,
+        DWORD dwDevType,
+        LPDIENUMDEVICESCALLBACKW lpCallback,
+        LPVOID pvRef,
+        DWORD dwFlags)
+{
+    dprintf("ZInput: %s\n", __func__);
+
+    return S_OK;
+}
+
+static HRESULT WINAPI hook_SetDataFormat(
+        IDirectInputDevice8W *self,
+        LPCDIDATAFORMAT lpdf)
+{
+    dprintf("ZInput: %s\n", __func__);
+
+    return S_OK;
+}
+
+static HRESULT WINAPI hook_SetCooperativeLevel(
+        IDirectInputDevice8W *self,
+        HWND hwnd,
+        DWORD flags)
+{
+    dprintf("ZInput: %s\n", __func__);
+
+    return S_OK;
+}
+
+static HRESULT WINAPI hook_Acquire(IDirectInputDevice8W *self)
+{
+    return S_OK;
+}
+
+static HRESULT WINAPI hook_Unacquire(IDirectInputDevice8W *self)
+{
+    return S_OK;
+}
+
+static HRESULT WINAPI hook_GetDeviceState(
+        IDirectInputDevice8W *self,
+        DWORD cbData,
+        LPVOID lpvData)
+{
+    memset(lpvData, 0, cbData);
+
+    return S_OK;
+}

swdchook/zinput.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <windows.h>
+
+#include <stdbool.h>
+
+struct zinput_config {
+    bool enable;
+};
+
+HRESULT zinput_hook_init(struct zinput_config *cfg);

swdcio/backend.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <stdint.h>
+
+#include "swdcio/swdcio.h"
+
+struct swdc_io_backend {
+    void (*get_opbtns)(uint8_t *opbtn);
+    void (*get_gamebtns)(uint16_t *gamebtn);
+    void (*get_analogs)(struct swdc_io_analog_state *state);
+};

swdcio/config.c

@@ -0,0 +1,111 @@
+#include <windows.h>
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <wchar.h>
+
+#include "swdcio/config.h"
+
+void swdc_di_config_load(struct swdc_di_config *cfg, const wchar_t *filename)
+{
+    wchar_t key[8];
+    int i;
+
+    assert(cfg != NULL);
+    assert(filename != NULL);
+
+    GetPrivateProfileStringW(
+            L"dinput",
+            L"deviceName",
+            L"",
+            cfg->device_name,
+            _countof(cfg->device_name),
+            filename);
+
+    GetPrivateProfileStringW(
+            L"dinput",
+            L"brakeAxis",
+            L"RZ",
+            cfg->brake_axis,
+            _countof(cfg->brake_axis),
+            filename);
+
+    GetPrivateProfileStringW(
+            L"dinput",
+            L"accelAxis",
+            L"Y",
+            cfg->accel_axis,
+            _countof(cfg->accel_axis),
+            filename);
+
+    cfg->start = GetPrivateProfileIntW(L"dinput", L"start", 0, filename);
+    cfg->view_chg = GetPrivateProfileIntW(L"dinput", L"viewChg", 0, filename);
+    cfg->shift_dn = GetPrivateProfileIntW(L"dinput", L"shiftDn", 0, filename);
+    cfg->shift_up = GetPrivateProfileIntW(L"dinput", L"shiftUp", 0, filename);
+    cfg->wheel_green = GetPrivateProfileIntW(L"dinput", L"wheelGreen", 0, filename);
+    cfg->wheel_red = GetPrivateProfileIntW(L"dinput", L"wheelRed", 0, filename);
+    cfg->wheel_blue = GetPrivateProfileIntW(L"dinput", L"wheelBlue", 0, filename);
+    cfg->wheel_yellow = GetPrivateProfileIntW(L"dinput", L"wheelYellow", 0, filename);
+
+    cfg->reverse_brake_axis = GetPrivateProfileIntW(
+                            L"dinput",
+                            L"reverseBrakeAxis",
+                            0,
+                            filename);
+    cfg->reverse_accel_axis = GetPrivateProfileIntW(
+                            L"dinput",
+                            L"reverseAccelAxis",
+                            0,
+                            filename);
+}
+
+void swdc_xi_config_load(struct swdc_xi_config *cfg, const wchar_t *filename)
+{
+    assert(cfg != NULL);
+    assert(filename != NULL);
+
+    cfg->single_stick_steering = GetPrivateProfileIntW(
+                                L"io4",
+                                L"singleStickSteering",
+                                0,
+                                filename);
+}
+
+void swdc_io_config_load(struct swdc_io_config *cfg, const wchar_t *filename)
+{
+    assert(cfg != NULL);
+    assert(filename != NULL);
+
+    cfg->vk_test = GetPrivateProfileIntW(L"io4", L"test", '1', filename);
+    cfg->vk_service = GetPrivateProfileIntW(L"io4", L"service", '2', filename);
+    cfg->vk_coin = GetPrivateProfileIntW(L"io4", L"coin", '3', filename);
+    cfg->restrict_ = GetPrivateProfileIntW(L"io4", L"restrict", 97, filename);
+
+    GetPrivateProfileStringW(
+            L"io4",
+            L"mode",
+            L"xinput",
+            cfg->mode,
+            _countof(cfg->mode),
+            filename);
+
+    swdc_shifter_config_load(&cfg->shifter, filename);
+    swdc_di_config_load(&cfg->di, filename);
+    swdc_xi_config_load(&cfg->xi, filename);
+}
+
+void swdc_shifter_config_load(
+        struct swdc_shifter_config *cfg,
+        const wchar_t *filename)
+{
+    assert(cfg != NULL);
+    assert(filename != NULL);
+
+    cfg->auto_neutral = GetPrivateProfileIntW(
+            L"io4",
+            L"autoNeutral",
+            0,
+            filename);
+}

swdcio/config.h

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+struct swdc_shifter_config {
+    bool auto_neutral;
+};
+
+struct swdc_di_config {
+    wchar_t device_name[64];
+    wchar_t brake_axis[16];
+    wchar_t accel_axis[16];
+    uint8_t start;
+    uint8_t view_chg;
+    uint8_t shift_dn;
+    uint8_t shift_up;
+    uint8_t wheel_green;
+    uint8_t wheel_red;
+    uint8_t wheel_blue;
+    uint8_t wheel_yellow;
+    bool reverse_brake_axis;
+    bool reverse_accel_axis;
+};
+
+struct swdc_xi_config {
+    bool single_stick_steering;
+};
+
+struct swdc_io_config {
+    uint8_t vk_test;
+    uint8_t vk_service;
+    uint8_t vk_coin;
+    wchar_t mode[8];
+    int restrict_;
+    struct swdc_shifter_config shifter;
+    struct swdc_di_config di;
+    struct swdc_xi_config xi;
+};
+
+void swdc_di_config_load(struct swdc_di_config *cfg, const wchar_t *filename);
+void swdc_xi_config_load(struct swdc_xi_config *cfg, const wchar_t *filename);
+void swdc_io_config_load(struct swdc_io_config *cfg, const wchar_t *filename);
+void swdc_shifter_config_load(
+        struct swdc_shifter_config *cfg,
+        const wchar_t *filename);

swdcio/di-dev.c

@@ -0,0 +1,163 @@
+#include <windows.h>
+#include <dinput.h>
+
+#include <assert.h>
+
+#include "swdcio/di-dev.h"
+
+#include "util/dprintf.h"
+
+HRESULT swdc_di_dev_start(IDirectInputDevice8W *dev, HWND wnd)
+{
+    HRESULT hr;
+
+    assert(dev != NULL);
+    assert(wnd != NULL);
+
+    hr = IDirectInputDevice8_SetCooperativeLevel(
+            dev,
+            wnd,
+            DISCL_BACKGROUND | DISCL_EXCLUSIVE);
+
+    if (FAILED(hr)) {
+        dprintf("DirectInput: SetCooperativeLevel failed: %08x\n", (int) hr);
+
+        return hr;
+    }
+
+    hr = IDirectInputDevice8_SetDataFormat(dev, &c_dfDIJoystick);
+
+    if (FAILED(hr)) {
+        dprintf("DirectInput: SetDataFormat failed: %08x\n", (int) hr);
+
+        return hr;
+    }
+
+    hr = IDirectInputDevice8_Acquire(dev);
+
+    if (FAILED(hr)) {
+        dprintf("DirectInput: Acquire failed: %08x\n", (int) hr);
+
+        return hr;
+    }
+
+    return hr;
+}
+
+void swdc_di_dev_start_fx(IDirectInputDevice8W *dev, IDirectInputEffect **out)
+{
+    /* Set up force-feedback on devices that support it. This is just a stub
+       for the time being, since we don't yet know how the serial port force
+       feedback protocol works.
+
+       I'm currently developing with an Xbox One Thrustmaster TMX wheel, if
+       we don't perform at least some perfunctory FFB initialization of this
+       nature (or indeed if no DirectInput application is running) then the
+       wheel exhibits considerable resistance, similar to that of a stationary
+       car. Changing cf.lMagnitude to a nonzero value does cause the wheel to
+       continuously turn in the given direction with the given force as one
+       would expect (max magnitude per DirectInput docs is +/- 10000).
+
+       Failure here is non-fatal, we log any errors and move on.
+
+       https://docs.microsoft.com/en-us/previous-versions/windows/desktop/ee416353(v=vs.85)
+    */
+
+    IDirectInputEffect *obj;
+    DWORD axis;
+    LONG direction;
+    DIEFFECT fx;
+    DICONSTANTFORCE cf;
+    HRESULT hr;
+
+    assert(dev != NULL);
+    assert(out != NULL);
+
+    *out = NULL;
+
+    dprintf("DirectInput: Starting force feedback (may take a sec)\n");
+
+    axis = DIJOFS_X;
+    direction = 0;
+
+    memset(&cf, 0, sizeof(cf));
+    cf.lMagnitude = 0;
+
+    memset(&fx, 0, sizeof(fx));
+    fx.dwSize = sizeof(fx);
+    fx.dwFlags = DIEFF_CARTESIAN | DIEFF_OBJECTOFFSETS;
+    fx.dwDuration = INFINITE;
+    fx.dwGain = DI_FFNOMINALMAX;
+    fx.dwTriggerButton = DIEB_NOTRIGGER;
+    fx.dwTriggerRepeatInterval = INFINITE;
+    fx.cAxes = 1;
+    fx.rgdwAxes = &axis;
+    fx.rglDirection = &direction;
+    fx.cbTypeSpecificParams = sizeof(cf);
+    fx.lpvTypeSpecificParams = &cf;
+
+    hr = IDirectInputDevice8_CreateEffect(
+            dev,
+            &GUID_ConstantForce,
+            &fx,
+            &obj,
+            NULL);
+
+    if (FAILED(hr)) {
+        dprintf("DirectInput: DirectInput force feedback unavailable: %08x\n",
+                (int) hr);
+
+        return;
+    }
+
+    hr = IDirectInputEffect_Start(obj, INFINITE, 0);
+
+    if (FAILED(hr)) {
+        IDirectInputEffect_Release(obj);
+        dprintf("DirectInput: DirectInput force feedback start failed: %08x\n",
+                (int) hr);
+
+        return;
+    }
+
+    *out = obj;
+
+    dprintf("DirectInput: Force feedback initialized and set to zero\n");
+}
+
+HRESULT swdc_di_dev_poll(
+        IDirectInputDevice8W *dev,
+        HWND wnd,
+        union swdc_di_state *out)
+{
+    HRESULT hr;
+    MSG msg;
+
+    assert(dev != NULL);
+    assert(wnd != NULL);
+    assert(out != NULL);
+
+    memset(out, 0, sizeof(*out));
+
+    /* Pump our dummy window's message queue just in case DirectInput or an
+       IHV DirectInput driver somehow relies on it */
+
+    while (PeekMessageW(&msg, wnd, 0, 0, PM_REMOVE)) {
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+
+    hr = IDirectInputDevice8_GetDeviceState(
+            dev,
+            sizeof(out->st),
+            &out->st);
+
+    if (FAILED(hr)) {
+        dprintf("DirectInput: GetDeviceState error: %08x\n", (int) hr);
+    }
+
+    /* JVS lacks a protocol for reporting hardware errors from poll command
+       responses, so this ends up returning zeroed input state instead. */
+
+    return hr;
+}

swdcio/di-dev.h

@@ -0,0 +1,19 @@
+#pragma once
+
+#include <windows.h>
+#include <dinput.h>
+
+#include <stdint.h>
+
+union swdc_di_state {
+    DIJOYSTATE st;
+    uint8_t bytes[sizeof(DIJOYSTATE)];
+};
+
+HRESULT swdc_di_dev_start(IDirectInputDevice8W *dev, HWND wnd);
+void swdc_di_dev_start_fx(IDirectInputDevice8W *dev, IDirectInputEffect **out);
+HRESULT swdc_di_dev_poll(
+        IDirectInputDevice8W *dev,
+        HWND wnd,
+        union swdc_di_state *out);
+

swdcio/di.c

@@ -0,0 +1,420 @@
+#include <windows.h>
+#include <dinput.h>
+
+#include <stddef.h>
+#include <stdint.h>
+#include <wchar.h>
+
+#include "swdcio/backend.h"
+#include "swdcio/config.h"
+#include "swdcio/di.h"
+#include "swdcio/di-dev.h"
+#include "swdcio/swdcio.h"
+#include "swdcio/wnd.h"
+
+#include "util/dprintf.h"
+#include "util/str.h"
+
+struct swdc_di_axis {
+    wchar_t name[4];
+    size_t off;
+};
+
+static HRESULT swdc_di_config_apply(const struct swdc_di_config *cfg);
+static const struct swdc_di_axis *swdc_di_get_axis(const wchar_t *name);
+static BOOL CALLBACK swdc_di_enum_callback(
+        const DIDEVICEINSTANCEW *dev,
+        void *ctx);
+static BOOL CALLBACK swdc_di_enum_callback_shifter(
+        const DIDEVICEINSTANCEW *dev,
+        void *ctx);
+static void swdc_di_get_buttons(uint16_t *gamebtn_out);
+static uint8_t swdc_di_decode_pov(DWORD pov);
+static void swdc_di_get_analogs(struct swdc_io_analog_state *out);
+
+static const struct swdc_di_axis swdc_di_axes[] = {
+    /* Just map DIJOYSTATE for now, we can map DIJOYSTATE2 later if needed */
+    { .name = L"X",     .off = DIJOFS_X },
+    { .name = L"Y",     .off = DIJOFS_Y },
+    { .name = L"Z",     .off = DIJOFS_Z },
+    { .name = L"RX",    .off = DIJOFS_RX },
+    { .name = L"RY",    .off = DIJOFS_RY },
+    { .name = L"RZ",    .off = DIJOFS_RZ },
+    { .name = L"U",     .off = DIJOFS_SLIDER(0) },
+    { .name = L"V",     .off = DIJOFS_SLIDER(1) },
+};
+
+static const struct swdc_io_backend swdc_di_backend = {
+    .get_gamebtns   = swdc_di_get_buttons,
+    .get_analogs   = swdc_di_get_analogs,
+};
+
+static HWND swdc_di_wnd;
+static IDirectInput8W *swdc_di_api;
+static IDirectInputDevice8W *swdc_di_dev;
+static IDirectInputEffect *swdc_di_fx;
+static size_t swdc_di_off_brake;
+static size_t swdc_di_off_accel;
+static uint8_t swdc_di_shift_dn;
+static uint8_t swdc_di_shift_up;
+static uint8_t swdc_di_view_chg;
+static uint8_t swdc_di_start;
+static uint8_t swdc_di_wheel_green;
+static uint8_t swdc_di_wheel_red;
+static uint8_t swdc_di_wheel_blue;
+static uint8_t swdc_di_wheel_yellow;
+static bool swdc_di_reverse_brake_axis;
+static bool swdc_di_reverse_accel_axis;
+
+HRESULT swdc_di_init(
+        const struct swdc_di_config *cfg,
+        HINSTANCE inst,
+        const struct swdc_io_backend **backend)
+{
+    HRESULT hr;
+    HMODULE dinput8;
+    HRESULT (WINAPI *api_entry)(HINSTANCE,DWORD,REFIID,LPVOID *,LPUNKNOWN);
+    wchar_t dll_path[MAX_PATH];
+    UINT path_pos;
+
+    assert(cfg != NULL);
+    assert(backend != NULL);
+
+    *backend = NULL;
+
+    hr = swdc_di_config_apply(cfg);
+
+    if (FAILED(hr)) {
+        return hr;
+    }
+
+    hr = swdc_io_wnd_create(inst, &swdc_di_wnd);
+
+    if (FAILED(hr)) {
+        return hr;
+    }
+
+    /* SWDC has some built-in DirectInput support that is not
+       particularly useful. swdchook shorts this out by redirecting dinput8.dll
+       to a no-op implementation of DirectInput. However, swdcio does need to
+       talk to the real operating system implementation of DirectInput without
+       the stub DLL interfering, so build a path to
+       C:\Windows\System32\dinput.dll here. */
+
+    dll_path[0] = L'\0';
+    path_pos = GetSystemDirectoryW(dll_path, _countof(dll_path));
+    wcscat_s(
+            dll_path + path_pos,
+            _countof(dll_path) - path_pos,
+            L"\\dinput8.dll");
+
+    dinput8 = LoadLibraryW(dll_path);
+
+    if (dinput8 == NULL) {
+        hr = HRESULT_FROM_WIN32(GetLastError());
+        dprintf("DirectInput: LoadLibrary failed: %08x\n", (int) hr);
+
+        return hr;
+    }
+
+    api_entry = (void *) GetProcAddress(dinput8, "DirectInput8Create");
+
+    if (api_entry == NULL) {
+        dprintf("DirectInput: GetProcAddress failed\n");
+
+        return E_FAIL;
+    }
+
+    hr = api_entry(
+            inst,
+            DIRECTINPUT_VERSION,
+            &IID_IDirectInput8W,
+            (void **) &swdc_di_api,
+            NULL);
+
+    if (FAILED(hr)) {
+        dprintf("DirectInput: API create failed: %08x\n", (int) hr);
+
+        return hr;
+    }
+
+    hr = IDirectInput8_EnumDevices(
+            swdc_di_api,
+            DI8DEVCLASS_GAMECTRL,
+            swdc_di_enum_callback,
+            (void *) cfg,
+            DIEDFL_ATTACHEDONLY);
+
+    if (FAILED(hr)) {
+        dprintf("DirectInput: EnumDevices failed: %08x\n", (int) hr);
+
+        return hr;
+    }
+
+    if (swdc_di_dev == NULL) {
+        dprintf("Wheel: Controller not found\n");
+
+        return HRESULT_FROM_WIN32(ERROR_FILE_NOT_FOUND);
+    }
+
+    hr = swdc_di_dev_start(swdc_di_dev, swdc_di_wnd);
+
+    if (FAILED(hr)) {
+        return hr;
+    }
+
+    swdc_di_dev_start_fx(swdc_di_dev, &swdc_di_fx);
+
+    dprintf("DirectInput: Controller initialized\n");
+
+    *backend = &swdc_di_backend;
+
+    return S_OK;
+}
+
+static HRESULT swdc_di_config_apply(const struct swdc_di_config *cfg)
+{
+    const struct swdc_di_axis *brake_axis;
+    const struct swdc_di_axis *accel_axis;
+    int i;
+
+    brake_axis = swdc_di_get_axis(cfg->brake_axis);
+    accel_axis = swdc_di_get_axis(cfg->accel_axis);
+
+    if (brake_axis == NULL) {
+        dprintf("Wheel: Invalid brake axis: %S\n", cfg->brake_axis);
+
+        return E_INVALIDARG;
+    }
+
+    if (accel_axis == NULL) {
+        dprintf("Wheel: Invalid accel axis: %S\n", cfg->accel_axis);
+
+        return E_INVALIDARG;
+    }
+
+    if (cfg->start > 32) {
+        dprintf("Wheel: Invalid start button: %i\n", cfg->start);
+
+        return E_INVALIDARG;
+    }
+
+    if (cfg->view_chg > 32) {
+        dprintf("Wheel: Invalid view change button: %i\n", cfg->view_chg);
+
+        return E_INVALIDARG;
+    }
+
+    if (cfg->shift_dn > 32) {
+        dprintf("Wheel: Invalid shift down button: %i\n", cfg->shift_dn);
+
+        return E_INVALIDARG;
+    }
+
+    if (cfg->shift_up > 32) {
+        dprintf("Wheel: Invalid shift up button: %i\n", cfg->shift_up);
+
+        return E_INVALIDARG;
+    }
+
+    if (cfg->wheel_green > 32) {
+        dprintf("Wheel: Invalid steering wheel green button: %i\n", cfg->wheel_green);
+
+        return E_INVALIDARG;
+    }
+    
+    if (cfg->wheel_red > 32) {
+        dprintf("Wheel: Invalid steering wheel red button: %i\n", cfg->wheel_red);
+
+        return E_INVALIDARG;
+    }
+    
+    if (cfg->wheel_blue > 32) {
+        dprintf("Wheel: Invalid steering wheel blue button: %i\n", cfg->wheel_blue);
+
+        return E_INVALIDARG;
+    }
+    
+    if (cfg->wheel_yellow > 32) {
+        dprintf("Wheel: Invalid steering wheel yellow button: %i\n", cfg->wheel_yellow);
+
+        return E_INVALIDARG;
+    }
+
+    /* Print some debug output to make sure config works... */
+
+    dprintf("Wheel: --- Begin configuration ---\n");
+    dprintf("Wheel: Device name . . . . : Contains \"%S\"\n",
+            cfg->device_name);
+    dprintf("Wheel: Brake axis . . . . . . : %S\n", accel_axis->name);
+    dprintf("Wheel: Accelerator axis . . . : %S\n", brake_axis->name);
+    dprintf("Wheel: Start button . . . . . : %i\n", cfg->start);
+    dprintf("Wheel: View Change button . . : %i\n", cfg->view_chg);
+    dprintf("Wheel: Shift Down button  . . : %i\n", cfg->shift_dn);
+    dprintf("Wheel: Shift Up button  . . . : %i\n", cfg->shift_up);
+    dprintf("Wheel: Steering Green button  : %i\n", cfg->wheel_green);
+    dprintf("Wheel: Steering Red button  . : %i\n", cfg->wheel_red);
+    dprintf("Wheel: Steering Blue button . : %i\n", cfg->wheel_blue);
+    dprintf("Wheel: Steering Yellow button : %i\n", cfg->wheel_yellow);
+    dprintf("Wheel: Reverse Brake Axis . . : %i\n", cfg->reverse_brake_axis);
+    dprintf("Wheel: Reverse Accel Axis . . : %i\n", cfg->reverse_accel_axis);
+    dprintf("Wheel: ---  End  configuration ---\n");
+
+    swdc_di_off_brake = accel_axis->off;
+    swdc_di_off_accel = brake_axis->off;
+    swdc_di_start = cfg->start;
+    swdc_di_view_chg = cfg->view_chg;
+    swdc_di_shift_dn = cfg->shift_dn;
+    swdc_di_shift_up = cfg->shift_up;
+    swdc_di_wheel_green = cfg->wheel_green;
+    swdc_di_wheel_red = cfg->wheel_red;
+    swdc_di_wheel_blue = cfg->wheel_blue;
+    swdc_di_wheel_yellow = cfg->wheel_yellow;
+    swdc_di_reverse_brake_axis = cfg->reverse_brake_axis;
+    swdc_di_reverse_accel_axis = cfg->reverse_accel_axis;
+
+    return S_OK;
+}
+
+static const struct swdc_di_axis *swdc_di_get_axis(const wchar_t *name)
+{
+    const struct swdc_di_axis *axis;
+    size_t i;
+
+    for (i = 0 ; i < _countof(swdc_di_axes) ; i++) {
+        axis = &swdc_di_axes[i];
+
+        if (wstr_ieq(name, axis->name)) {
+            return axis;
+        }
+    }
+
+    return NULL;
+}
+
+static BOOL CALLBACK swdc_di_enum_callback(
+        const DIDEVICEINSTANCEW *dev,
+        void *ctx)
+{
+    const struct swdc_di_config *cfg;
+    HRESULT hr;
+
+    cfg = ctx;
+
+    if (wcsstr(dev->tszProductName, cfg->device_name) == NULL) {
+        return DIENUM_CONTINUE;
+    }
+
+    dprintf("Wheel: Using DirectInput device \"%S\"\n", dev->tszProductName);
+
+    hr = IDirectInput8_CreateDevice(
+            swdc_di_api,
+            &dev->guidInstance,
+            &swdc_di_dev,
+            NULL);
+
+    if (FAILED(hr)) {
+        dprintf("Wheel: CreateDevice failed: %08x\n", (int) hr);
+    }
+
+    return DIENUM_STOP;
+}
+
+static void swdc_di_get_buttons(uint16_t *gamebtn_out)
+{
+    union swdc_di_state state;
+    uint8_t gamebtn;
+    HRESULT hr;
+
+    assert(gamebtn_out != NULL);
+
+    hr = swdc_di_dev_poll(swdc_di_dev, swdc_di_wnd, &state);
+
+    if (FAILED(hr)) {
+        return;
+    }
+
+    gamebtn = swdc_di_decode_pov(state.st.rgdwPOV[0]);
+
+    if (swdc_di_start && state.st.rgbButtons[swdc_di_start - 1]) {
+        gamebtn |= SWDC_IO_GAMEBTN_START;
+    }
+
+    if (swdc_di_view_chg && state.st.rgbButtons[swdc_di_view_chg - 1]) {
+        gamebtn |= SWDC_IO_GAMEBTN_VIEW_CHANGE;
+    }
+
+    if (swdc_di_shift_dn && state.st.rgbButtons[swdc_di_shift_dn - 1]) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_PADDLE_LEFT;
+    }
+
+    if (swdc_di_shift_up && state.st.rgbButtons[swdc_di_shift_up - 1]) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_PADDLE_RIGHT;
+    }
+
+    if (swdc_di_wheel_green && state.st.rgbButtons[swdc_di_wheel_green - 1]) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_GREEN;
+    }
+
+    if (swdc_di_wheel_red && state.st.rgbButtons[swdc_di_wheel_red - 1]) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_RED;
+    }
+
+    if (swdc_di_wheel_blue && state.st.rgbButtons[swdc_di_wheel_blue - 1]) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_BLUE;
+    }
+
+    if (swdc_di_wheel_yellow && state.st.rgbButtons[swdc_di_wheel_yellow - 1]) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_YELLOW;
+    }
+
+    *gamebtn_out = gamebtn;
+}
+
+static uint8_t swdc_di_decode_pov(DWORD pov)
+{
+    switch (pov) {
+        case 0:     return SWDC_IO_GAMEBTN_UP;
+        case 4500:  return SWDC_IO_GAMEBTN_UP | SWDC_IO_GAMEBTN_RIGHT;
+        case 9000:  return SWDC_IO_GAMEBTN_RIGHT;
+        case 13500: return SWDC_IO_GAMEBTN_RIGHT | SWDC_IO_GAMEBTN_DOWN;
+        case 18000: return SWDC_IO_GAMEBTN_DOWN;
+        case 22500: return SWDC_IO_GAMEBTN_DOWN | SWDC_IO_GAMEBTN_RIGHT;
+        case 27000: return SWDC_IO_GAMEBTN_LEFT;
+        case 31500: return SWDC_IO_GAMEBTN_LEFT | SWDC_IO_GAMEBTN_UP;
+        default:    return 0;
+    }
+}
+
+static void swdc_di_get_analogs(struct swdc_io_analog_state *out)
+{
+    union swdc_di_state state;
+    const LONG *brake;
+    const LONG *accel;
+    HRESULT hr;
+
+    assert(out != NULL);
+
+    hr = swdc_di_dev_poll(swdc_di_dev, swdc_di_wnd, &state);
+
+    if (FAILED(hr)) {
+        return;
+    }
+
+    brake = (LONG *) &state.bytes[swdc_di_off_brake];
+    accel = (LONG *) &state.bytes[swdc_di_off_accel];
+
+    out->wheel = state.st.lX - 32768;
+
+    if (swdc_di_reverse_brake_axis) {
+        out->brake = *brake;
+    } else {
+        out->brake = 65535 - *brake;
+    }
+
+    if (swdc_di_reverse_accel_axis) {
+        out->accel = *accel;
+    } else {
+        out->accel = 65535 - *accel;
+    }
+}

swdcio/di.h

@@ -0,0 +1,9 @@
+#pragma once
+
+#include "swdcio/backend.h"
+#include "swdcio/config.h"
+
+HRESULT swdc_di_init(
+        const struct swdc_di_config *cfg,
+        HINSTANCE inst,
+        const struct swdc_io_backend **backend);

swdcio/dllmain.c

@@ -0,0 +1,112 @@
+#include <windows.h>
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "swdcio/backend.h"
+#include "swdcio/config.h"
+#include "swdcio/di.h"
+#include "swdcio/swdcio.h"
+#include "swdcio/xi.h"
+
+#include "util/dprintf.h"
+#include "util/str.h"
+
+static struct swdc_io_config swdc_io_cfg;
+static const struct swdc_io_backend *swdc_io_backend;
+static bool swdc_io_coin;
+
+uint16_t swdc_io_get_api_version(void)
+{
+    return 0x0100;
+}
+
+HRESULT swdc_io_init(void)
+{
+    HINSTANCE inst;
+    HRESULT hr;
+
+    assert(swdc_io_backend == NULL);
+
+    inst = GetModuleHandleW(NULL);
+
+    if (inst == NULL) {
+        hr = HRESULT_FROM_WIN32(GetLastError());
+        dprintf("GetModuleHandleW failed: %lx\n", hr);
+
+        return hr;
+    }
+
+    swdc_io_config_load(&swdc_io_cfg, L".\\segatools.ini");
+
+    if (wstr_ieq(swdc_io_cfg.mode, L"dinput")) {
+        hr = swdc_di_init(&swdc_io_cfg.di, inst, &swdc_io_backend);
+    } else if (wstr_ieq(swdc_io_cfg.mode, L"xinput")) {
+        hr = swdc_xi_init(&swdc_io_cfg.xi, &swdc_io_backend);
+    } else {
+        hr = E_INVALIDARG;
+        dprintf("swdc IO: Invalid IO mode \"%S\", use dinput or xinput\n",
+                swdc_io_cfg.mode);
+    }
+
+    return hr;
+}
+
+void swdc_io_get_opbtns(uint8_t *opbtn_out)
+{
+    uint8_t opbtn;
+
+    assert(swdc_io_backend != NULL);
+    assert(opbtn_out != NULL);
+
+    opbtn = 0;
+
+    if (GetAsyncKeyState(swdc_io_cfg.vk_test) & 0x8000) {
+        opbtn |= SWDC_IO_OPBTN_TEST;
+    }
+
+    if (GetAsyncKeyState(swdc_io_cfg.vk_service) & 0x8000) {
+        opbtn |= SWDC_IO_OPBTN_SERVICE;
+    }
+
+    if (GetAsyncKeyState(swdc_io_cfg.vk_coin) & 0x8000) {
+        if (!swdc_io_coin) {
+            swdc_io_coin = true;
+            opbtn |= SWDC_IO_OPBTN_COIN;
+        }
+    } else {
+        swdc_io_coin = false;
+    }
+
+    *opbtn_out = opbtn;
+}
+
+
+void swdc_io_get_gamebtns(uint16_t *gamebtn_out)
+{
+    assert(swdc_io_backend != NULL);
+    assert(gamebtn_out != NULL);
+
+    swdc_io_backend->get_gamebtns(gamebtn_out);
+}
+
+void swdc_io_get_analogs(struct swdc_io_analog_state *out)
+{
+    struct swdc_io_analog_state tmp;
+
+    assert(out != NULL);
+    assert(swdc_io_backend != NULL);
+
+    swdc_io_backend->get_analogs(&tmp);
+
+    /* Apply steering wheel restriction. Real cabs only report about 77% of
+       the IO-3's max ADC output value when the wheel is turned to either of
+       its maximum positions. To match this behavior we set the default value
+       for the wheel restriction config parameter to 97 (out of 128). This
+       scaling factor is applied using fixed-point arithmetic below. */
+
+    out->wheel = (tmp.wheel * swdc_io_cfg.restrict_) / 128;
+    out->accel = tmp.accel;
+    out->brake = tmp.brake;
+}

swdcio/meson.build

@@ -0,0 +1,30 @@
+swdcio_lib = static_library(
+    'swdccio',
+    name_prefix : '',
+    include_directories : inc,
+    implicit_include_directories : false,
+    c_pch : '../precompiled.h',
+    dependencies : [
+        dinput8_lib,
+        dxguid_lib,
+        xinput_lib,
+    ],
+    link_with : [
+        util_lib,
+    ],
+    sources : [
+        'backend.h',
+        'config.c',
+        'config.h',
+        'di.c',
+        'di.h',
+        'di-dev.c',
+        'di-dev.h',
+        'dllmain.c',
+        'swdcio.h',
+        'wnd.c',
+        'wnd.h',
+        'xi.c',
+        'xi.h',
+    ],
+)

swdcio/swdcio.def

@@ -0,0 +1,8 @@
+LIBRARY swdcio
+
+EXPORTS
+    swdc_io_init
+    swdc_io_poll
+    swdc_io_get_opbtns
+    swdc_io_get_gamebtns
+    swdc_io_get_analogs

swdcio/swdcio.h

@@ -0,0 +1,98 @@
+#pragma once
+
+#include <windows.h>
+
+#include <stdint.h>
+
+enum {
+    SWDC_IO_OPBTN_TEST = 0x01,
+    SWDC_IO_OPBTN_SERVICE = 0x02,
+    SWDC_IO_OPBTN_COIN = 0x04,
+};
+
+enum {
+    SWDC_IO_GAMEBTN_UP = 0x01,
+    SWDC_IO_GAMEBTN_DOWN = 0x02,
+    SWDC_IO_GAMEBTN_LEFT = 0x04,
+    SWDC_IO_GAMEBTN_RIGHT = 0x08,
+    SWDC_IO_GAMEBTN_START = 0x10,
+    SWDC_IO_GAMEBTN_VIEW_CHANGE = 0x20,
+
+    SWDC_IO_GAMEBTN_STEERING_BLUE = 0x40,
+    SWDC_IO_GAMEBTN_STEERING_GREEN = 0x80,
+    SWDC_IO_GAMEBTN_STEERING_RED = 0x100,
+    SWDC_IO_GAMEBTN_STEERING_YELLOW = 0x200,
+    SWDC_IO_GAMEBTN_STEERING_PADDLE_LEFT = 0x400,
+    SWDC_IO_GAMEBTN_STEERING_PADDLE_RIGHT = 0x800,
+};
+
+struct swdc_io_analog_state {
+    /* Current steering wheel position, where zero is the centered position.
+
+       The game will accept any signed 16-bit position value, however a real
+       cabinet will report a value of approximately +/- 25230 when the wheel
+       is at full lock. Steering wheel positions of a magnitude greater than
+       this value are not possible on a real cabinet. */
+
+    int16_t wheel;
+
+    /* Current position of the accelerator pedal, where 0 is released. */
+
+    uint16_t accel;
+
+    /* Current position of the brake pedal, where 0 is released. */
+
+    uint16_t brake;
+};
+
+/* Get the version of the IDAC IO API that this DLL supports. This
+   function should return a positive 16-bit integer, where the high byte is
+   the major version and the low byte is the minor version (as defined by the
+   Semantic Versioning standard).
+
+   The latest API version as of this writing is 0x0100. */
+
+uint16_t swdc_io_get_api_version(void);
+
+/* Initialize the IO DLL. This is the second function that will be called on
+   your DLL, after mu3_io_get_api_version.
+
+   All subsequent calls to this API may originate from arbitrary threads.
+
+   Minimum API version: 0x0100 */
+
+HRESULT swdc_io_init(void);
+
+/* Send any queued outputs (of which there are currently none, though this may
+   change in subsequent API versions) and retrieve any new inputs.
+
+   Minimum API version: 0x0100 */
+
+HRESULT swdc_io_poll(void);
+
+/* Get the state of the cabinet's operator buttons as of the last poll. See
+   MU3_IO_OPBTN enum above: this contains bit mask definitions for button
+   states returned in *opbtn. All buttons are active-high.
+
+   Minimum API version: 0x0100 */
+
+void swdc_io_get_opbtns(uint8_t *opbtn);
+
+/* Get the state of the cabinet's gameplay buttons as of the last poll. See
+   MU3_IO_GAMEBTN enum above for bit mask definitions. Inputs are split into
+   a left hand side set of inputs and a right hand side set of inputs: the bit
+   mappings are the same in both cases.
+
+   All buttons are active-high, even though some buttons' electrical signals
+   on a real cabinet are active-low.
+
+   Minimum API version: 0x0100 */
+
+void swdc_io_get_gamebtns(uint16_t *gamebtn);
+
+/* Poll the current state of the cabinet's JVS analog inputs. See structure
+   definition above for details.
+
+   Minimum API version: 0x0100 */
+
+void swdc_io_get_analogs(struct swdc_io_analog_state *out);

swdcio/wnd.c

@@ -0,0 +1,86 @@
+#include <windows.h>
+
+#include <assert.h>
+#include <string.h>
+
+#include "util/dprintf.h"
+
+/* DirectInput requires a window for correct initialization (and also force
+   feedback), so this source file provides some utilities for creating a
+   generic message-only window. */
+
+static LRESULT WINAPI swdc_io_wnd_proc(
+            HWND hwnd,
+            UINT msg,
+            WPARAM wparam,
+            LPARAM lparam);
+
+HRESULT swdc_io_wnd_create(HINSTANCE inst, HWND *out)
+{
+    HRESULT hr;
+    WNDCLASSEXW wcx;
+    ATOM atom;
+    HWND hwnd;
+
+    assert(inst != NULL); /* We are not an EXE */
+    assert(out != NULL);
+
+    *out = NULL;
+
+    memset(&wcx, 0, sizeof(wcx));
+    wcx.cbSize = sizeof(wcx);
+    wcx.lpfnWndProc = swdc_io_wnd_proc;
+    wcx.hInstance = inst;
+    wcx.lpszClassName = L"SWDCIO";
+
+    atom = RegisterClassExW(&wcx);
+
+    if (atom == 0) {
+        hr = HRESULT_FROM_WIN32(GetLastError());
+        dprintf("SWDCIO: RegisterClassExW failed: %08x\n", (int) hr);
+
+        goto fail;
+    }
+
+    hwnd = CreateWindowExW(
+            0,
+            (wchar_t *) (intptr_t) atom,
+            L"",
+            0,
+            CW_USEDEFAULT,
+            CW_USEDEFAULT,
+            CW_USEDEFAULT,
+            CW_USEDEFAULT,
+            HWND_MESSAGE,
+            NULL,
+            inst,
+            NULL);
+
+    if (hwnd == NULL) {
+        hr = HRESULT_FROM_WIN32(GetLastError());
+        dprintf("SWDCIO: CreateWindowExW failed: %08x\n", (int) hr);
+
+        goto fail;
+    }
+
+    *out = hwnd;
+
+    return S_OK;
+
+fail:
+    UnregisterClassW((wchar_t *) (intptr_t) atom, inst);
+
+    return hr;
+}
+
+static LRESULT WINAPI swdc_io_wnd_proc(
+            HWND hwnd,
+            UINT msg,
+            WPARAM wparam,
+            LPARAM lparam)
+{
+    switch (msg) {
+    default:
+        return DefWindowProcW(hwnd, msg, wparam, lparam);
+    }
+}

swdcio/wnd.h

@@ -0,0 +1,5 @@
+#pragma once
+
+#include <windows.h>
+
+HRESULT swdc_io_wnd_create(HINSTANCE inst, HWND *out);

swdcio/xi.c

@@ -0,0 +1,165 @@
+#include <windows.h>
+#include <xinput.h>
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "swdcio/backend.h"
+#include "swdcio/config.h"
+#include "swdcio/swdcio.h"
+#include "swdcio/xi.h"
+
+#include "util/dprintf.h"
+
+static void swdc_xi_get_gamebtns(uint16_t *gamebtn_out);
+static void swdc_xi_get_analogs(struct swdc_io_analog_state *out);
+
+static HRESULT swdc_xi_config_apply(const struct swdc_xi_config *cfg);
+
+static const struct swdc_io_backend swdc_xi_backend = {
+    .get_gamebtns  = swdc_xi_get_gamebtns,
+    .get_analogs   = swdc_xi_get_analogs,
+};
+
+static bool swdc_xi_single_stick_steering;
+
+HRESULT swdc_xi_init(const struct swdc_xi_config *cfg, const struct swdc_io_backend **backend)
+{
+    HRESULT hr;
+    assert(cfg != NULL);
+    assert(backend != NULL);
+
+    hr = swdc_xi_config_apply(cfg);
+
+    if (FAILED(hr)) {
+        return hr;
+    }
+
+    dprintf("XInput: Using XInput controller\n");
+    *backend = &swdc_xi_backend;
+
+    return S_OK;
+}
+
+HRESULT swdc_io_poll(void)
+{    
+    return S_OK;
+}
+
+static HRESULT swdc_xi_config_apply(const struct swdc_xi_config *cfg)
+{
+    dprintf("XInput: --- Begin configuration ---\n");
+    dprintf("XInput: Single Stick Steering : %i\n", cfg->single_stick_steering);
+    dprintf("XInput: ---  End  configuration ---\n");
+
+    swdc_xi_single_stick_steering = cfg->single_stick_steering;
+
+    return S_OK;
+}
+
+static void swdc_xi_get_gamebtns(uint16_t *gamebtn_out)
+{
+    uint16_t gamebtn;
+    XINPUT_STATE xi;
+    WORD xb;
+
+    assert(gamebtn_out != NULL);
+
+    gamebtn = 0;
+
+    memset(&xi, 0, sizeof(xi));
+    XInputGetState(0, &xi);
+    xb = xi.Gamepad.wButtons;
+
+    if (xb & XINPUT_GAMEPAD_DPAD_UP) {
+        gamebtn |= SWDC_IO_GAMEBTN_UP;
+    }
+
+    if (xb & XINPUT_GAMEPAD_DPAD_DOWN) {
+        gamebtn |= SWDC_IO_GAMEBTN_DOWN;
+    }
+
+    if (xb & XINPUT_GAMEPAD_DPAD_LEFT) {
+        gamebtn |= SWDC_IO_GAMEBTN_LEFT;
+    }
+
+    if (xb & XINPUT_GAMEPAD_DPAD_RIGHT) {
+        gamebtn |= SWDC_IO_GAMEBTN_RIGHT;
+    }
+
+    if (xb & XINPUT_GAMEPAD_START) {
+        gamebtn |= SWDC_IO_GAMEBTN_START;
+    }
+
+    if (xb & XINPUT_GAMEPAD_BACK) {
+        gamebtn |= SWDC_IO_GAMEBTN_VIEW_CHANGE;
+    }
+
+    if (xb & XINPUT_GAMEPAD_A) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_GREEN;
+    }
+
+    if (xb & XINPUT_GAMEPAD_B) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_RED;
+    }
+
+    if (xb & XINPUT_GAMEPAD_X) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_BLUE;
+    }
+
+    if (xb & XINPUT_GAMEPAD_Y) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_YELLOW;
+    }
+
+    if (xb & XINPUT_GAMEPAD_LEFT_SHOULDER) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_PADDLE_LEFT;
+    }
+
+    if (xb & XINPUT_GAMEPAD_RIGHT_SHOULDER) {
+        gamebtn |= SWDC_IO_GAMEBTN_STEERING_PADDLE_RIGHT;
+    }
+
+    *gamebtn_out = gamebtn;
+}
+
+static void swdc_xi_get_analogs(struct swdc_io_analog_state *out)
+{
+    XINPUT_STATE xi;
+    int left;
+    int right;
+
+    assert(out != NULL);
+
+    memset(&xi, 0, sizeof(xi));
+    XInputGetState(0, &xi);
+
+    left = xi.Gamepad.sThumbLX;
+
+    if (left < -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE) {
+        left += XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE;
+    } else if (left > XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE) {
+        left -= XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE;
+    } else {
+        left = 0;
+    }
+
+    right = xi.Gamepad.sThumbRX;
+
+    if (right < -XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE) {
+        right += XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE;
+    } else if (right > XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE) {
+        right -= XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE;
+    } else {
+        right = 0;
+    }
+
+    if (swdc_xi_single_stick_steering) {
+        out->wheel = left;
+    } else {
+        out->wheel = (left + right) / 2;
+    }
+
+    out->accel = xi.Gamepad.bRightTrigger << 8;
+    out->brake = xi.Gamepad.bLeftTrigger << 8;
+}

swdcio/xi.h

@@ -0,0 +1,10 @@
+#pragma once
+
+/* Can't call this xinput.h or it will conflict with <xinput.h> */
+
+#include <windows.h>
+
+#include "swdcio/backend.h"
+#include "swdcio/config.h"
+
+HRESULT swdc_xi_init(const struct swdc_xi_config *cfg, const struct swdc_io_backend **backend);