test: Add a unit test for input device classification heuristics

This uses pre-recorded evdev capabilities, so that we can check for
regressions without the devices having to be physically present.

Signed-off-by: Simon McVittie <smcv@collabora.com>

2 files changed, 1035 insertions, 0 deletions

diff --git a/test/Makefile.in b/test/Makefile.in
index 41fa6039e..4e514ff31 100644
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -24,6 +24,7 @@ TARGETS = \
 	testdrawchessboard$(EXE) \
 	testdropfile$(EXE) \
 	testerror$(EXE) \
+	testevdev$(EXE) \
 	testfile$(EXE) \
 	testfilesystem$(EXE) \
 	testgamecontroller$(EXE) \
@@ -148,6 +149,9 @@ testdropfile$(EXE): $(srcdir)/testdropfile.c
 testerror$(EXE): $(srcdir)/testerror.c
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
 
+testevdev$(EXE): $(srcdir)/testevdev.c
+	$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
+
 testfile$(EXE): $(srcdir)/testfile.c
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
 
diff --git a/test/testevdev.c b/test/testevdev.c
new file mode 100644
index 000000000..9ed3eff34
--- /dev/null
+++ b/test/testevdev.c
@@ -0,0 +1,1031 @@
+/*
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+  Copyright (C) 2020 Collabora Ltd.
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely.
+*/
+
+#include "../src/SDL_internal.h"
+
+#include <stdio.h>
+#include <string.h>
+
+static int run_test(void);
+
+#if HAVE_LIBUDEV_H || defined(SDL_JOYSTICK_LINUX)
+
+#include <stdint.h>
+
+#include "SDL_stdinc.h"
+#include "SDL_endian.h"
+#include "../src/core/linux/SDL_evdev_capabilities.h"
+#include "../src/core/linux/SDL_evdev_capabilities.c"
+
+static const struct
+{
+    int code;
+    const char *name;
+} device_classes[] =
+{
+#define CLS(x) \
+    { SDL_UDEV_DEVICE_ ## x, #x }
+    CLS(MOUSE),
+    CLS(KEYBOARD),
+    CLS(JOYSTICK),
+    CLS(SOUND),
+    CLS(TOUCHSCREEN),
+    CLS(ACCELEROMETER),
+#undef CLS
+    { 0, NULL }
+};
+
+typedef struct
+{
+  const char *name;
+  uint16_t bus_type;
+  uint16_t vendor_id;
+  uint16_t product_id;
+  uint16_t version;
+  uint8_t ev[(EV_MAX + 1) / 8];
+  uint8_t keys[(KEY_MAX + 1) / 8];
+  uint8_t abs[(ABS_MAX + 1) / 8];
+  uint8_t rel[(REL_MAX + 1) / 8];
+  uint8_t ff[(FF_MAX + 1) / 8];
+  uint8_t props[INPUT_PROP_MAX / 8];
+  int expected;
+} GuessTest;
+
+/*
+ * Test-cases for guessing a device type from its capabilities.
+ *
+ * The bytes in ev, etc. are in little-endian byte order
+ * Trailing zeroes can be omitted.
+ *
+ * The evemu-describe tool is a convenient way to add a test-case for
+ * a physically available device.
+ */
+#define ZEROx4 0, 0, 0, 0
+#define ZEROx8 ZEROx4, ZEROx4
+#define FFx4 0xff, 0xff, 0xff, 0xff
+#define FFx8 FFx4, FFx4
+
+/* Test-cases derived from real devices or from Linux kernel source */
+static const GuessTest guess_tests[] =
+{
+    {
+      .name = "Xbox 360 wired USB controller",
+      .bus_type = 0x0003,
+      .vendor_id = 0x045e,
+      .product_id = 0x028e,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS, FF */
+      .ev = { 0x0b, 0x00, 0x20 },
+      /* X, Y, Z, RX, RY, RZ, HAT0X, HAT0Y */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, SELECT, START, MODE, THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7c,
+      },
+    },
+    {
+      .name = "X-Box One Elite",
+      .bus_type = 0x0003,
+      .vendor_id = 0x045e,
+      .product_id = 0x02e3,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RX, RY, RZ, HAT0X, HAT0Y */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, SELECT, START, MODE, THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7c,
+      },
+    },
+    {
+      .name = "X-Box One S via Bluetooth",
+      .bus_type = 0x0005,
+      .vendor_id = 0x045e,
+      .product_id = 0x02e0,
+      .version = 0x1130,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RX, RY, RZ, HAT0X, HAT0Y */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, SELECT, START, MODE, THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7c,
+      },
+    },
+    {
+      .name = "X-Box One S wired",
+      .bus_type = 0x0003,
+      .vendor_id = 0x045e,
+      .product_id = 0x02ea,
+      .version = 0x0301,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RX, RY, RZ, HAT0X, HAT0Y */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, SELECT, START, MODE, THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7c,
+      },
+    },
+    {
+      .name = "DualShock 4 - gamepad",
+      .bus_type = 0x0003,
+      .vendor_id = 0x054c,
+      .product_id = 0x09cc,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS, MSC, FF */
+      /* Some versions only have 0x0b, SYN, KEY, ABS, like the
+       * Bluetooth example below */
+      .ev = { 0x1b, 0x00, 0x20 },
+      /* X, Y, Z, RX, RY, RZ, HAT0X, HAT0Y */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, TL2, TR2, SELECT, START, MODE,
+           * THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7f,
+      },
+    },
+    {
+      .name = "DualShock 4 - gamepad via Bluetooth",
+      .bus_type = 0x0005,
+      .vendor_id = 0x054c,
+      .product_id = 0x09cc,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RX, RY, RZ, HAT0X, HAT0Y */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, TL2, TR2, SELECT, START, MODE,
+           * THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7f,
+      },
+    },
+    {
+      .name = "DualShock 4 - touchpad",
+      .bus_type = 0x0003,
+      .vendor_id = 0x054c,
+      .product_id = 0x09cc,
+      /* TODO: Should this be MOUSE? That's what it most closely
+       * resembles */
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, multitouch */
+      .abs = { 0x03, 0x00, 0x00, 0x00, 0x00, 0x80, 0x60, 0x02 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* Left mouse button */
+          /* 0x100 */ 0x00, 0x00, 0x01, 0x00, ZEROx4,
+          /* BTN_TOOL_FINGER and some multitouch stuff */
+          /* 0x140 */ 0x20, 0x24, 0x00, 0x00
+      },
+      /* POINTER, BUTTONPAD */
+      .props = { 0x05 },
+    },
+    {
+      .name = "DualShock 4 - accelerometer",
+      .bus_type = 0x0003,
+      .vendor_id = 0x054c,
+      .product_id = 0x09cc,
+      .expected = SDL_UDEV_DEVICE_ACCELEROMETER,
+      /* SYN, ABS, MSC */
+      .ev = { 0x19 },
+      /* X, Y, Z, RX, RY, RZ */
+      .abs = { 0x3f },
+      /* ACCELEROMETER */
+      .props = { 0x40 },
+    },
+    {
+      .name = "DualShock 4 via USB dongle",
+      .bus_type = 0x0003,
+      .vendor_id = 0x054c,
+      .product_id = 0x0ba0,
+      .version = 0x8111,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, ABS, KEY */
+      .ev = { 0x0b },
+      /* X, Y, Z, RX, RY, RZ, HAT0X, HAT0Y */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, TL2, TR2, SELECT, START, MODE,
+           * THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7f,
+      },
+    },
+    {
+      .name = "DualShock 3 - gamepad",
+      .bus_type = 0x0003,
+      .vendor_id = 0x054c,
+      .product_id = 0x0268,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS, MSC, FF */
+      .ev = { 0x1b, 0x00, 0x20 },
+      /* X, Y, Z, RX, RY, RZ */
+      .abs = { 0x3f },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, TL2, TR2, SELECT, START, MODE,
+           * THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7f,
+          /* 0x140 */ ZEROx8,
+          /* 0x180 */ ZEROx8,
+          /* 0x1c0 */ ZEROx8,
+          /* Digital dpad */
+          /* 0x200 */ ZEROx4, 0x0f, 0x00, 0x00, 0x00,
+      },
+    },
+    {
+      .name = "DualShock 3 - accelerometer",
+      .bus_type = 0x0003,
+      .vendor_id = 0x054c,
+      .product_id = 0x0268,
+      .expected = SDL_UDEV_DEVICE_ACCELEROMETER,
+      /* SYN, ABS */
+      .ev = { 0x09 },
+      /* X, Y, Z */
+      .abs = { 0x07 },
+      /* ACCELEROMETER */
+      .props = { 0x40 },
+    },
+    {
+      .name = "Steam Controller - gamepad",
+      .bus_type = 0x0003,
+      .vendor_id = 0x28de,
+      .product_id = 0x1142,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, RX, RY, HAT0X, HAT0Y, HAT2X, HAT2Y */
+      .abs = { 0x1b, 0x00, 0x33 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, TL2, TR2, SELECT, START, MODE,
+           * THUMBL, THUMBR, joystick THUMB, joystick THUMB2  */
+          /* 0x100 */ ZEROx4, 0x06, 0x00, 0xdb, 0x7f,
+          /* GEAR_DOWN, GEAR_UP */
+          /* 0x140 */ 0x00, 0x00, 0x03, 0x00, ZEROx4,
+          /* 0x180 */ ZEROx8,
+          /* 0x1c0 */ ZEROx8,
+          /* Digital dpad */
+          /* 0x200 */ ZEROx4, 0x0f, 0x00, 0x00, 0x00,
+      },
+    },
+    {
+      /* Present to support lizard mode, even if no Steam Controller
+       * is connected */
+      .name = "Steam Controller - dongle",
+      .bus_type = 0x0003,
+      .vendor_id = 0x28de,
+      .product_id = 0x1142,
+      .expected = (SDL_UDEV_DEVICE_KEYBOARD
+                   | SDL_UDEV_DEVICE_MOUSE),
+      /* SYN, KEY, REL, MSC, LED, REP */
+      .ev = { 0x17, 0x00, 0x12 },
+      /* X, Y, mouse wheel, high-res mouse wheel */
+      .rel = { 0x03, 0x09 },
+      .keys = {
+          /* 0x00 */ 0xfe, 0xff, 0xff, 0xff, FFx4,
+          /* 0x40 */ 0xff, 0xff, 0xcf, 0x01, 0xdf, 0xff, 0x80, 0xe0,
+          /* 0x80 */ ZEROx8,
+          /* 0xc0 */ ZEROx8,
+          /* 0x100 */ 0x00, 0x00, 0x1f, 0x00, ZEROx4,
+      },
+    },
+    {
+      .name = "Guitar Hero for PS3",
+      .bus_type = 0x0003,
+      .vendor_id = 0x12ba,
+      .product_id = 0x0100,
+      .version = 0x0110,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RZ, HAT0X, HAT0Y */
+      .abs = { 0x27, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* ABC, XYZ, TL, TR, TL2, TR2, SELECT, START, MODE */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xff, 0x1f,
+      },
+    },
+    {
+      .name = "G27 Racing Wheel, 0003:046d:c29b v0111",
+      .bus_type = 0x0003,
+      .vendor_id = 0x046d,
+      .product_id = 0xc29b,
+      .version = 0x0111,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RZ, HAT0X, HAT0Y */
+      .abs = { 0x27, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* 16 buttons: TRIGGER, THUMB, THUMB2, TOP, TOP2, PINKIE, BASE,
+           * BASE2..BASE6, unregistered event codes 0x12c-0x12e, DEAD */
+          /* 0x100 */ ZEROx4, 0xff, 0xff, 0x00, 0x00,
+          /* 0x140 */ ZEROx8,
+          /* 0x180 */ ZEROx8,
+          /* 0x1c0 */ ZEROx8,
+          /* 0x200 */ ZEROx8,
+          /* 0x240 */ ZEROx8,
+          /* 0x280 */ ZEROx8,
+          /* TRIGGER_HAPPY1..TRIGGER_HAPPY7 */
+          /* 0x2c0 */ 0x7f,
+      },
+    },
+    {
+      .name = "Logitech Driving Force, 0003:046d:c294 v0100",
+      .bus_type = 0x0003,
+      .vendor_id = 0x046d,
+      .product_id = 0xc294,
+      .version = 0x0100,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, RZ, HAT0X, HAT0Y */
+      .abs = { 0x23, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* 12 buttons: TRIGGER, THUMB, THUMB2, TOP, TOP2, PINKIE, BASE,
+           * BASE2..BASE6 */
+          /* 0x100 */ ZEROx4, 0xff, 0x0f, 0x00, 0x00,
+      },
+    },
+    {
+      .name = "Logitech Dual Action",
+      .bus_type = 0x0003,
+      .vendor_id = 0x046d,
+      .product_id = 0xc216,
+      .version = 0x0110,
+      /* Logitech RumblePad 2 USB, 0003:046d:c218 v0110, is the same
+       * except for having force feedback, which we don't use in our
+       * heuristic */
+      /* Jess Tech GGE909 PC Recoil Pad, 0003:0f30:010b v0110, is the same */
+      /* 8BitDo SNES30, 0003:2dc8:ab20 v0110, is the same */
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RZ, HAT0X, HAT0Y */
+      .abs = { 0x27, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* 12 buttons: TRIGGER, THUMB, THUMB2, TOP, TOP2, PINKIE, BASE,
+           * BASE2..BASE6 */
+          /* 0x100 */ ZEROx4, 0xff, 0x0f, 0x00, 0x00,
+      },
+    },
+    {
+      .name = "Saitek ST290 Pro flight stick",
+      .bus_type = 0x0003,
+      .vendor_id = 0x06a3,
+      .product_id = 0x0160,   /* 0x0460 seems to be the same */
+      .version = 0x0100,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS, MSC */
+      .ev = { 0x1b },
+      /* X, Y, Z, RZ, HAT0X, HAT0Y */
+      .abs = { 0x27, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* TRIGGER, THUMB, THUMB2, TOP, TOP2, PINKIE */
+          /* 0x100 */ ZEROx4, 0x3f, 0x00, 0x00, 0x00,
+      },
+    },
+    {
+      .name = "Saitek X52 Pro Flight Control System",
+      .bus_type = 0x0003,
+      .vendor_id = 0x06a3,
+      .product_id = 0x0762,
+      .version = 0x0111,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      .ev = { 0x0b },
+      /* XYZ, RXYZ, throttle, hat0, MISC, unregistered event code 0x29 */
+      .abs = { 0x7f, 0x00, 0x03, 0x00, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* 16 buttons: TRIGGER, THUMB, THUMB2, TOP, TOP2, PINKIE, BASE,
+           * BASE2..BASE6, unregistered event codes 0x12c-0x12e, DEAD */
+          /* 0x100 */ ZEROx4, 0xff, 0xff, 0x00, 0x00,
+          /* 0x140 */ ZEROx8,
+          /* 0x180 */ ZEROx8,
+          /* 0x1c0 */ ZEROx8,
+          /* 0x200 */ ZEROx8,
+          /* 0x240 */ ZEROx8,
+          /* 0x280 */ ZEROx8,
+          /* TRIGGER_HAPPY1..TRIGGER_HAPPY23 */
+          /* 0x2c0 */ 0xff, 0xff, 0x7f,
+      },
+    },
+    {
+      .name = "Logitech Extreme 3D",
+      .bus_type = 0x0003,
+      .vendor_id = 0x046d,
+      .product_id = 0xc215,
+      .version = 0x0110,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS, MSC */
+      .ev = { 0x0b },
+      /* X, Y, RZ, throttle, hat 0 */
+      .abs = { 0x63, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* 12 buttons: TRIGGER, THUMB, THUMB2, TOP, TOP2, PINKIE, BASE,
+           * BASE2..BASE6 */
+          /* 0x100 */ ZEROx4, 0xff, 0x0f, 0x00, 0x00,
+      },
+    },
+    {
+      .name = "Hori Real Arcade Pro VX-SA",
+      .bus_type = 0x0003,
+      .vendor_id = 0x24c6,
+      .product_id = 0x5501,
+      .version = 0x0533,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RX, RY, RZ, hat 0 */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, SELECT, START, MODE, THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7c,
+      },
+    },
+    {
+      .name = "Switch Pro Controller via Bluetooth",
+      .bus_type = 0x0005,
+      .vendor_id = 0x057e,
+      .product_id = 0x2009,
+      .version = 0x0001,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, RX, RY, hat 0 */
+      .abs = { 0x1b, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* 16 buttons: TRIGGER, THUMB, THUMB2, TOP, TOP2, PINKIE, BASE,
+           * BASE2..BASE6, unregistered event codes 0x12c-0x12e, DEAD */
+          /* 0x100 */ ZEROx4, 0xff, 0xff, 0x00, 0x00,
+          /* 0x140 */ ZEROx8,
+          /* 0x180 */ ZEROx8,
+          /* 0x1c0 */ ZEROx8,
+          /* 0x200 */ ZEROx8,
+          /* 0x240 */ ZEROx8,
+          /* 0x280 */ ZEROx8,
+          /* TRIGGER_HAPPY1..TRIGGER_HAPPY2 */
+          /* 0x2c0 */ 0x03,
+      },
+    },
+    {
+      .name = "Switch Pro Controller via USB",
+      .bus_type = 0x0003,
+      .vendor_id = 0x057e,
+      .product_id = 0x2009,
+      .version = 0x0111,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, Z, RZ, HAT0X, HAT0Y */
+      .abs = { 0x27, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+      },
+    },
+    {
+      .name = "Thrustmaster Racing Wheel FFB",
+      /* Mad Catz FightStick TE S+ PS4, 0003:0738:8384:0111 v0111
+       * (aka Street Fighter V Arcade FightStick TES+)
+       * is functionally the same */
+      .bus_type = 0x0003,
+      .vendor_id = 0x044f,
+      .product_id = 0xb66d,
+      .version = 0x0110,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      .ev = { 0x0b },
+      /* XYZ, RXYZ, hat 0 */
+      .abs = { 0x3f, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* ABC, XYZ, TL, TR, TL2, TR2, SELECT, START, MODE,
+           * THUMBL */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xff, 0x3f,
+      },
+    },
+    {
+      .name = "Thrustmaster T.Flight Hotas X",
+      .bus_type = 0x0003,
+      .vendor_id = 0x044f,
+      .product_id = 0xb108,
+      .version = 0x0100,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      .ev = { 0x0b },
+      /* XYZ, RZ, throttle, hat 0 */
+      .abs = { 0x67, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* trigger, thumb, thumb2, top, top2, pinkie, base,
+           * base2..base6 */
+          /* 0x100 */ ZEROx4, 0xff, 0x0f
+      },
+    },
+    {
+      .name = "8BitDo N30 Pro 2",
+      .bus_type = 0x0003,
+      .vendor_id = 0x2dc8,
+      .product_id = 0x9015,
+      .version = 0x0111,
+      /* 8BitDo NES30 Pro, 0003:2dc8:9001 v0111, is the same */
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      .ev = { 0x0b },
+      /* XYZ, RZ, gas, brake, hat0 */
+      .abs = { 0x27, 0x06, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* ABC, XYZ, TL, TR, TL2, TR2, select, start, mode, thumbl,
+           * thumbr */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xff, 0x7f,
+      },
+    },
+    {
+      .name = "Retro Power SNES-style controller, 0003:0079:0011 v0110",
+      .bus_type = 0x0003,
+      .vendor_id = 0x0079,
+      .product_id = 0x0011,
+      .version = 0x0110,
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      .ev = { 0x0b },
+      /* X, Y */
+      .abs = { 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* trigger, thumb, thumb2, top, top2, pinkie, base,
+           * base2..base4 */
+          /* 0x100 */ ZEROx4, 0xff, 0x03, 0x00, 0x00,
+      },
+    },
+    {
+      .name = "Wiimote - buttons",
+      .bus_type = 0x0005,
+      .vendor_id = 0x057e,
+      .product_id = 0x0306,
+      .version = 0x8600,
+      /* This one is a bit weird because some of the buttons are mapped
+       * to the arrow, page up and page down keys, so it's a joystick
+       * with a subset of a keyboard attached. */
+      /* TODO: Should this be JOYSTICK, or even JOYSTICK|KEYBOARD? */
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY */
+      .ev = { 0x03 },
+      .keys = {
+          /* 0x00 */ ZEROx8,
+          /* left, right, up down */
+          /* 0x40 */ ZEROx4, 0x80, 0x16, 0x00, 0x00,
+          /* 0x80 */ ZEROx8,
+          /* 0xc0 */ ZEROx8,
+          /* BTN_1, BTN_2, BTN_A, BTN_B, BTN_MODE */
+          /* 0x100 */ 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0x10,
+          /* 0x140 */ ZEROx8,
+          /* next, previous */
+          /* 0x180 */ 0x00, 0x00, 0x80, 0x10, ZEROx4,
+      },
+    },
+    {
+      .name = "Wiimote - Motion Plus or accelerometer",
+      .bus_type = 0x0005,
+      .vendor_id = 0x057e,
+      .product_id = 0x0306,
+      .version = 0x8600,
+      .expected = SDL_UDEV_DEVICE_ACCELEROMETER,
+      /* SYN, ABS */
+      .ev = { 0x09 },
+      /* RX, RY, RZ */
+      .abs = { 0x38 },
+    },
+    {
+      .name = "Wiimote - IR positioning",
+      .bus_type = 0x0005,
+      .vendor_id = 0x057e,
+      .product_id = 0x0306,
+      .version = 0x8600,
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, ABS */
+      .ev = { 0x09 },
+      /* HAT0 to HAT3 */
+      .abs = { 0x00, 0x1f },
+    },
+    {
+      .name = "Wiimote - Nunchuck",
+      .bus_type = 0x0005,
+      .vendor_id = 0x057e,
+      .product_id = 0x0306,
+      .version = 0x8600,
+      /* TODO: Should this be JOYSTICK? It has one stick and two buttons */
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* RX, RY, RZ, hat 0 */
+      .abs = { 0x38, 0x00, 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+         /* C and Z buttons */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0x24, 0x00,
+      },
+    },
+    {
+      /* Flags guessed from kernel source code */
+      .name = "Wiimote - Classic Controller",
+      /* TODO: Should this be JOYSTICK, or maybe JOYSTICK|KEYBOARD?
+       * It's unusual in the same ways as the Wiimote */
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* Hat 1-3 */
+      .abs = { 0x00, 0x1c },
+      .keys = {
+          /* 0x00 */ ZEROx8,
+          /* left, right, up down */
+          /* 0x40 */ ZEROx4, 0x80, 0x16, 0x00, 0x00,
+          /* 0x80 */ ZEROx8,
+          /* 0xc0 */ ZEROx8,
+          /* A, B, X, Y, MODE, TL, TL2, TR, TR2 */
+          /* 0x100 */ ZEROx4, 0x00, 0x13, 0xdb, 0x10,
+          /* 0x140 */ ZEROx8,
+          /* next, previous */
+          /* 0x180 */ 0x00, 0x00, 0x80, 0x10, ZEROx4,
+      },
+    },
+    {
+      /* Flags guessed from kernel source code */
+      .name = "Wiimote - Balance Board",
+      /* TODO: Should this be JOYSTICK? */
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* Hat 0-1 */
+      .abs = { 0x00, 0x0f },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0x01, 0x00,
+      },
+    },
+    {
+      /* Flags guessed from kernel source code */
+      .name = "Wiimote - Wii U Pro Controller",
+      .expected = SDL_UDEV_DEVICE_JOYSTICK,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, RX, RY */
+      .abs = { 0x1b },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* A, B, X, Y, TL, TR, TL2, TR2, SELECT, START, MODE,
+           * THUMBL, THUMBR */
+          /* 0x100 */ ZEROx4, 0x00, 0x00, 0xdb, 0x7f,
+          /* 0x140 */ ZEROx8,
+          /* 0x180 */ ZEROx8,
+          /* 0x1c0 */ ZEROx8,
+          /* Digital dpad */
+          /* 0x200 */ ZEROx4, 0x0f, 0x00, 0x00, 0x00,
+      },
+    },
+    {
+      .name = "Synaptics TM3381-002 (Thinkpad X280 trackpad)",
+      .bus_type = 0x001d,   /* BUS_RMI */
+      .vendor_id = 0x06cb,
+      .product_id = 0x0000,
+      .version = 0x0000,
+      /* TODO: Should this be MOUSE? That's what it most closely
+       * resembles */
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY, ABS */
+      .ev = { 0x0b },
+      /* X, Y, pressure, multitouch */
+      .abs = { 0x03, 0x00, 0x00, 0x01, 0x00, 0x80, 0xf3, 0x06 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* Left mouse button */
+          /* 0x100 */ 0x00, 0x00, 0x01, 0x00, ZEROx4,
+          /* BTN_TOOL_FINGER and some multitouch gestures */
+          /* 0x140 */ 0x20, 0xe5
+      },
+      /* POINTER, BUTTONPAD */
+      .props = { 0x05 },
+    },
+    {
+      .name = "TPPS/2 Elan TrackPoint (Thinkpad X280)",
+      .bus_type = 0x0011,   /* BUS_I8042 */
+      .vendor_id = 0x0002,
+      .product_id = 0x000a,
+      .version = 0x0000,
+      .expected = SDL_UDEV_DEVICE_MOUSE,
+      /* SYN, KEY, REL */
+      .ev = { 0x07 },
+      /* X, Y */
+      .rel = { 0x03 },
+      .keys = {
+          /* 0x00-0xff */ ZEROx8, ZEROx8, ZEROx8, ZEROx8,
+          /* Left, middle, right mouse buttons */
+          /* 0x100 */ 0x00, 0x00, 0x07,
+      },
+      /* POINTER, POINTING_STICK */
+      .props = { 0x21 },
+    },
+    {
+      .name = "Thinkpad ACPI buttons",
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY, MSC, SW */
+      .ev = { 0x33 },
+      .keys = {
+          /* 0x00 */ ZEROx8,
+          /* 0x40 */ ZEROx4, 0x00, 0x00, 0x0e, 0x01,
+          /* 0x80 */ 0x00, 0x50, 0x11, 0x51, 0x00, 0x28, 0x00, 0xc0,
+          /* 0xc0 */ 0x04, 0x20, 0x10, 0x02, 0x1b, 0x70, 0x01, 0x00,
+          /* 0x100 */ ZEROx8,
+          /* 0x140 */ ZEROx4, 0x00, 0x00, 0x50, 0x00,
+          /* 0x180 */ ZEROx8,
+          /* 0x1c0 */ 0x00, 0x00, 0x04, 0x18, ZEROx4,
+          /* 0x200 */ ZEROx8,
+          /* 0x240 */ 0x40, 0x00, 0x01, 0x00, ZEROx4,
+      },
+    },
+    {
+      .name = "PC speaker",
+      .bus_type = 0x0010,   /* BUS_ISA */
+      .vendor_id = 0x001f,
+      .product_id = 0x0001,
+      .version = 0x0100,
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, SND */
+      .ev = { 0x01, 0x00, 0x04 },
+    },
+    {
+      .name = "ALSA headphone detection, etc.",
+      .bus_type = 0x0000,
+      .vendor_id = 0x0000,
+      .product_id = 0x0000,
+      .version = 0x0000,
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, SW */
+      .ev = { 0x21 },
+    },
+    {
+      /* Assumed to be a reasonably typical i8042 (PC AT) keyboard */
+      .name = "Thinkpad T520 and X280 keyboards",
+      .bus_type = 0x0011,   /* BUS_I8042 */
+      .vendor_id = 0x0001,
+      .product_id = 0x0001,
+      .version = 0xab54,
+      .expected = SDL_UDEV_DEVICE_KEYBOARD,
+      /* SYN, KEY, MSC, LED, REP */
+      .ev = { 0x13, 0x00, 0x12 },
+      .keys = {
+          /* 0x00 */ 0xfe, 0xff, 0xff, 0xff, FFx4,
+          /* 0x40 */ 0xff, 0xff, 0xef, 0xff, 0xdf, 0xff, 0xff, 0xfe,
+          /* 0x80 */ 0x01, 0xd0, 0x00, 0xf8, 0x78, 0x30, 0x80, 0x03,
+          /* 0xc0 */ 0x00, 0x00, 0x00, 0x02, 0x04, 0x00, 0x00, 0x00,
+      },
+    },
+    {
+      .name = "Thinkpad X280 sleep button",
+      .bus_type = 0x0019,   /* BUS_HOST */
+      .vendor_id = 0x0000,
+      .product_id = 0x0003,
+      .version = 0x0000,
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY */
+      .ev = { 0x03 },
+      .keys = {
+          /* 0x00 */ ZEROx8,
+          /* 0x40 */ ZEROx8,
+          /* KEY_SLEEP */
+          /* 0x80 */ 0x00, 0x40,
+      },
+    },
+    {
+      .name = "Thinkpad X280 lid switch",
+      .bus_type = 0x0019,   /* BUS_HOST */
+      .vendor_id = 0x0000,
+      .product_id = 0x0005,
+      .version = 0x0000,
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, SW */
+      .ev = { 0x21 },
+    },
+    {
+      .name = "Thinkpad X280 power button",
+      .bus_type = 0x0019,   /* BUS_HOST */
+      .vendor_id = 0x0000,
+      .product_id = 0x0001,
+      .version = 0x0000,
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY */
+      .ev = { 0x03 },
+      .keys = {
+          /* 0x00 */ ZEROx8,
+          /* KEY_POWER */
+          /* 0x40 */ ZEROx4, 0x00, 0x00, 0x10, 0x00,
+      },
+    },
+    {
+      .name = "Thinkpad X280 video bus",
+      .bus_type = 0x0019,   /* BUS_HOST */
+      .vendor_id = 0x0000,
+      .product_id = 0x0006,
+      .version = 0x0000,
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY */
+      .ev = { 0x03 },
+      .keys = {
+          /* 0x00 */ ZEROx8,
+          /* 0x40 */ ZEROx8,
+          /* 0x80 */ ZEROx8,
+          /* brightness control, video mode, display off */
+          /* 0xc0 */ ZEROx4, 0x0b, 0x00, 0x3e, 0x00,
+      },
+    },
+    {
+      .name = "Thinkpad X280 extra buttons",
+      .bus_type = 0x0019,   /* BUS_HOST */
+      .vendor_id = 0x17aa,
+      .product_id = 0x5054,
+      .version = 0x4101,
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+      /* SYN, KEY */
+      .ev = { 0x03 },
+      .keys = {
+          /* 0x00 */ ZEROx8,
+          /* 0x40 */ ZEROx4, 0x00, 0x00, 0x0e, 0x01,
+          /* 0x80 */ 0x00, 0x50, 0x11, 0x51, 0x00, 0x28, 0x00, 0xc0,
+          /* 0xc0 */ 0x04, 0x20, 0x10, 0x02, 0x1b, 0x70, 0x01, 0x00,
+          /* 0x100 */ ZEROx8,
+          /* 0x140 */ ZEROx4, 0x00, 0x00, 0x50, 0x00,
+          /* 0x180 */ ZEROx8,
+          /* 0x1c0 */ 0x00, 0x00, 0x04, 0x18, ZEROx4,
+          /* 0x200 */ ZEROx8,
+          /* 0x240 */ 0x40, 0x00, 0x01, 0x00, ZEROx4,
+      },
+    },
+    {
+      .name = "Thinkpad USB keyboard with Trackpoint - keyboard",
+      .bus_type = 0x0003,
+      .vendor_id = 0x17ef,
+      .product_id = 0x6009,
+      .expected = SDL_UDEV_DEVICE_KEYBOARD,
+      /* SYN, KEY, MSC, LED, REP */
+      .ev = { 0x13, 0x00, 0x12 },
+      .keys = {
+          /* 0x00 */ 0xfe, 0xff, 0xff, 0xff, FFx4,
+          /* 0x40 */ 0xff, 0xff, 0xef, 0xff, 0xdf, 0xff, 0xbe, 0xfe,
+          /* 0x80 */ 0xff, 0x57, 0x40, 0xc1, 0x7a, 0x20, 0x9f, 0xff,
+          /* 0xc0 */ 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00,
+      },
+    },
+    {
+      .name = "Thinkpad USB keyboard with Trackpoint - Trackpoint",
+      .bus_type = 0x0003,
+      .vendor_id = 0x17ef,
+      .product_id = 0x6009,
+      /* For some reason the special keys like mute and wlan toggle
+       * show up here instead of, or in addition to, as part of
+       * the keyboard - so udev reports this as having keys too.
+       * SDL currently doesn't. */
+      .expected = SDL_UDEV_DEVICE_MOUSE,
+      /* SYN, KEY, REL, MSC, LED */
+      .ev = { 0x17, 0x00, 0x02 },
+      /* X, Y */
+      .rel = { 0x03 },
+      .keys = {
+          /* 0x00 */ ZEROx8,
+          /* 0x40 */ ZEROx4, 0x00, 0x00, 0x1e, 0x00,
+          /* 0x80 */ 0x00, 0xcc, 0x11, 0x01, 0x78, 0x40, 0x00, 0xc0,
+          /* 0xc0 */ 0x00, 0x20, 0x10, 0x00, 0x0b, 0x50, 0x00, 0x00,
+          /* Mouse buttons: left, right, middle, "task" */
+          /* 0x100 */ 0x00, 0x00, 0x87, 0x68, ZEROx4,
+          /* 0x140 */ ZEROx4, 0x00, 0x00, 0x10, 0x00,
+          /* 0x180 */ ZEROx4, 0x00, 0x00, 0x40, 0x00,
+      },
+    },
+    {
+      .name = "No information",
+      .expected = SDL_UDEV_DEVICE_UNKNOWN,
+    }
+};
+
+#if ULONG_MAX == 0xFFFFFFFFUL
+#   define SwapLongLE(X) SDL_SwapLE32(X)
+#else
+    /* assume 64-bit */
+#   define SwapLongLE(X) SDL_SwapLE64(X)
+#endif
+
+static int
+run_test(void)
+{
+    int success = 1;
+    size_t i;
+
+    for (i = 0; i < SDL_arraysize(guess_tests); i++) {
+        const GuessTest *t = &guess_tests[i];
+        size_t j;
+        int actual;
+        struct {
+            unsigned long ev[NBITS(EV_MAX)];
+            unsigned long abs[NBITS(ABS_MAX)];
+            unsigned long keys[NBITS(KEY_MAX)];
+            unsigned long rel[NBITS(REL_MAX)];
+        } caps = {};
+
+        printf("%s...\n", t->name);
+
+        memset(&caps, '\0', sizeof(caps));
+        memcpy(caps.ev, t->ev, sizeof(t->ev));
+        memcpy(caps.keys, t->keys, sizeof(t->keys));
+        memcpy(caps.abs, t->abs, sizeof(t->abs));
+        memcpy(caps.rel, t->rel, sizeof(t->rel));
+
+        for (j = 0; j < SDL_arraysize(caps.ev); j++) {
+            caps.ev[j] = SwapLongLE(caps.ev[j]);
+        }
+
+        for (j = 0; j < SDL_arraysize(caps.keys); j++) {
+            caps.keys[j] = SwapLongLE(caps.keys[j]);
+        }
+
+        for (j = 0; j < SDL_arraysize(caps.abs); j++) {
+            caps.abs[j] = SwapLongLE(caps.abs[j]);
+        }
+
+        for (j = 0; j < SDL_arraysize(caps.rel); j++) {
+            caps.rel[j] = SwapLongLE(caps.rel[j]);
+        }
+
+        actual = SDL_EVDEV_GuessDeviceClass(caps.ev, caps.abs, caps.keys,
+                                            caps.rel);
+
+        if (actual == t->expected) {
+            printf("\tOK\n");
+        }
+        else {
+            printf("\tExpected 0x%08x\n", t->expected);
+
+            for (j = 0; device_classes[j].code != 0; j++) {
+                if (t->expected & device_classes[j].code) {
+                    printf("\t\t%s\n", device_classes[j].name);
+                }
+            }
+
+            printf("\tGot      0x%08x\n", actual);
+
+            for (j = 0; device_classes[j].code != 0; j++) {
+                if (actual & device_classes[j].code) {
+                    printf("\t\t%s\n", device_classes[j].name);
+                }
+            }
+
+            success = 0;
+        }
+    }
+
+    return success;
+}
+
+#else /* !(HAVE_LIBUDEV_H || defined(SDL_JOYSTICK_LINUX)) */
+
+static int
+run_test(void)
+{
+    printf("SDL compiled without evdev capability check.\n");
+    return 0;
+}
+
+#endif
+
+int
+main(int argc, char *argv[])
+{
+    return run_test() ? 0 : 1;
+}