m + add controller fingerprint + relay less on libevdev

Signed-off-by: Mattias Andrée <maandree@kth.se>

9 files changed, 412 insertions, 83 deletions

diff --git a/TODO b/TODO
index 8cd3c2a..c82bd57 100644
--- a/TODO
+++ b/TODO
@@ -3,7 +3,7 @@ Add support for profiles (conformation, button names/icons/colours, controller l
 Add support for quirks
 Add support for leds
 Add support for accelerometer and gyroscope
-Add support for creating instance from a file descriptor
 Add man pages
 Add readme file
 Add force feedback tests
+Fix error details in .h documentation
diff --git a/common.h b/common.h
index aec4277..9889858 100644
--- a/common.h
+++ b/common.h
@@ -18,10 +18,24 @@
 #include <unistd.h>
 
 #include <libevdev/libevdev.h>
+#include <libsha2.h>
 #include <libudev.h>
 
 
+#if defined(__GNUC__)
+# define LIBGAMEPAD_CONST__ __attribute__((__const__))
+#else
+# define LIBGAMEPAD_CONST__
+#endif
+
+
+#define READ_(ARR, I) ((ARR)[(I) / BITSOF(*(ARR))])
+#define SHIFT_(ARR, I) ((I) % BITSOF(*(ARR)))
+
 #define ELEMSOF(A) (sizeof(A) / sizeof(*(A)))
+#define BITSOF(T) (8 * sizeof(T))
+#define SETBIT(ARR, I) (READ_(ARR, I) |= 1 << SHIFT_(ARR, I))
+#define GETBIT(ARR, I) ((READ_(ARR, I) >> SHIFT_(ARR, I)) & 1)
 
 
 struct libgamepad_attachment_monitor {
@@ -34,6 +48,8 @@ struct libgamepad_device_internals {
 	int close_fd;
 	int require_sync;
 	struct libevdev *dev;
+	struct input_absinfo *absinfo;
+	uint8_t *buttons;
 };
 
 
diff --git a/config.mk b/config.mk
index 8453750..7e9fb7c 100644
--- a/config.mk
+++ b/config.mk
@@ -9,6 +9,6 @@ CFLAGS   = -Wall -g
 LDFLAGS  =
 
 LIBS_CFLAGS = $$(pkg-config --cflags libevdev)
-LIBS_LDFLAGS = $$(pkg-config --libs libevdev) -ludev -lm
+LIBS_LDFLAGS = $$(pkg-config --libs libevdev) -ludev -lm -lsha2
 
 INPUT_EVENT_CODES_H = /usr/include/linux/input-event-codes.h
diff --git a/libgamepad.h b/libgamepad.h
index b0efec4..e7abd6a 100644
--- a/libgamepad.h
+++ b/libgamepad.h
@@ -15,6 +15,13 @@
 #include <libevdev/libevdev.h>
 
 
+#if defined(__GNUC__)
+# define LIBGAMEPAD_PURE__ __attribute__((__pure__))
+#else
+# define LIBGAMEPAD_PURE__
+#endif
+
+
 /**
  * Opaque structure for monitoring device attachment changes
  */
@@ -265,7 +272,6 @@ enum libgamepad_game_controller {
 	 *     Digital button "R" at upper right index finger position
 	 *     Digital button "ZL" at lower left index finger position
 	 *     Digital button "ZR" at lower right index finger position
-	 *     Digital Stadia (icon: brand) button between analogue sticks
 	 *     2 digital buttons at inner left thumb position:
 	 *     - North = "−"
 	 *     - East  = Capture (icon: circle; shape: square)
@@ -491,7 +497,30 @@ enum libgamepad_game_controller {
 	 * 
 	 * Released 2012-11-18 for Wii U
 	 * 
-	 * TODO Document Wii U Pro Controller
+	 * Layout:
+	 *     Clickable analogue stick at upper left thumb position
+	 *     Clickable analogue stick at upper right thumb position
+	 *     Digital D-pad at lower left thumb position
+	 *     4 digital buttons at lower right thumb position:
+	 *     - North = "X"
+	 *     - West  = "Y"
+	 *     - South = "B"
+	 *     - East  = "A"
+	 *     Digital button "L" at upper left index finger position
+	 *     Digital button "R" at upper right index finger position
+	 *     Digital button "ZL" at lower left index finger position
+	 *     Digital button "ZR" at lower right index finger position
+	 *     3 digital buttons at centre thumb position:
+	 *     - West   = "SELECT" (icon: minus symbol)
+	 *     - Centre = "HOME" (icon: house)
+	 *     - East   = "START" (icon: plus symbol)
+	 *     Digital "POWER" (icon: power symbol with the 1 over top
+	 *       of the 0, colour: red) button at lower center thumb position
+	 * 
+	 * Other features:
+	 * - Wireless via Bluetooth
+	 * - 4 digital LEDs numbered 1 through 4 (??)
+	 * - 1 digital LEDs labelled "BATTERY" (??)
 	 */
 	LIBGAMEPAD_CONTROLLER_WII_U_PRO,
 
@@ -525,9 +554,25 @@ enum libgamepad_game_controller {
 	/**
 	 * Classic Controller Pro
 	 * 
-	 * Released 2009-??-?? for Wii
+	 * Released 2009-08-01 for Wii
 	 * 
-	 * TODO Document Classic Controller Pro
+	 * Layout:
+	 *     Digital D-pad at upper left thumb position
+	 *     Analogue stick at lower left thumb position
+	 *     Analogue stick at lower right thumb position
+	 *     4 digital buttons at upper right thumb position:
+	 *     - North = "x"
+	 *     - West  = "y"
+	 *     - South = "b"
+	 *     - East  = "a"
+	 *     Digital button "L" at upper left index finger position
+	 *     Digital button "R" at upper right index finger position
+	 *     Digital button "ZL" at lower left index finger position
+	 *     Digital button "ZR" at lower right index finger position
+	 *     3 digital buttons at centre thumb position:
+	 *     - West   = "SELECT" (icon: minus symbol)
+	 *     - Centre = "HOME" (icon: house, colour: blue)
+	 *     - East   = "START" (icon: plus symbol)
 	 */
 	LIBGAMEPAD_CONTROLLER_WII_CLASSIC_PRO,
 
@@ -546,7 +591,23 @@ enum libgamepad_game_controller {
 	 * 
 	 * Released 2006-11-19 for Wii
 	 * 
-	 * TODO Document Classic Controller
+	 * Layout:
+	 *     Digital D-pad at upper left thumb position
+	 *     Analogue stick at lower left thumb position
+	 *     Analogue stick at lower right thumb position
+	 *     4 digital buttons at upper right thumb position:
+	 *     - North = "x"
+	 *     - West  = "y"
+	 *     - South = "b"
+	 *     - East  = "a"
+	 *     Analogue button "L" at left index finger position
+	 *     Analogue button "R" at right index finger position
+	 *     Digital button "ZL" inward from left index finger position
+	 *     Digital button "ZR" inward from right index finger position
+	 *     3 digital buttons at centre thumb position:
+	 *     - West   = "SELECT" (icon: minus symbol)
+	 *     - Centre = "HOME" (icon: house, colour: blue)
+	 *     - East   = "START" (icon: plus symbol)
 	 */
 	LIBGAMEPAD_CONTROLLER_WII_CLASSIC,
 
@@ -555,7 +616,14 @@ enum libgamepad_game_controller {
 	 * 
 	 * Released 2006-11-19 for Wii
 	 * 
-	 * TODO Document Nunchuk
+	 * Layout:
+	 *     Designed to be held in the user's dominant hand
+	 *     Analogue stick at thumb position
+	 *     Digital button "C" at upper index finger position
+	 *     Digital button "Z" at lower index finger position
+	 * 
+	 * Other features:
+	 * - Accelerometer
 	 */
 	LIBGAMEPAD_CONTROLLER_NUNCHUK,
 
@@ -574,6 +642,9 @@ enum libgamepad_game_controller {
 	 * Released 2010-10-28 for Wii
 	 * 
 	 * Adds (3 axis?) gyroscope to `LIBGAMEPAD_CONTROLLER_WII_REMOTE`
+	 * 
+	 * Conforming controllers:
+	 * - Wii Remote with Wii MotionPlus adapter
 	 */
 	LIBGAMEPAD_CONTROLLER_WII_REMOTE_PLUS,
 
@@ -763,7 +834,8 @@ enum libgamepad_game_controller {
 	 * 
 	 * Released 1997-11-20 for PlayStation
 	 * 
-	 * TODO Document DualShock Analog Controller
+	 * Adds rubble support to `LIBGAMEPAD_CONTROLLER_DUAL_ANALOG`
+	 * (TODO What does digital mode on DualShock do?)
 	 */
 	LIBGAMEPAD_CONTROLLER_DUAL_SHOCK,
 
@@ -771,8 +843,32 @@ enum libgamepad_game_controller {
 	 * Dual Analog Controller
 	 * 
 	 * Released 1997-04-25 for PlayStation
+	 *
+	 * The first Japanese version of this controller
+	 * had rumble support and is therefore better
+	 * reported as `LIBGAMEPAD_CONTROLLER_DUAL_SHOCK`
+	 * 
+	 * Layout:
+	 *     Digital D-pad at upper left thumb position
+	 *     Clickable analogue stick at lower left thumb position
+	 *     Clickable analogue stick at lower right thumb position
+	 *     4 digital buttons at upper right thumb position
+	 *     - North = Triangle (colour: green)
+	 *     - West  = Square (colour: pink)
+	 *     - South = Cross (colour: blue)
+	 *     - East  = Circle (colour: red)
+	 *     Digital button "L1" at upper left index finger position
+	 *     Digital button "R1" at upper right index finger position
+	 *     Digital button "L2" at lower left index finger position
+	 *     Digital button "R2" at lower right index finger position
+	 *     2 digital buttons at centre position:
+	 *     - West = "SELECT" (shape: flat rectangle)
+	 *     - East = "START"  (shape: flat play icon)
 	 * 
-	 * TODO Document Dual Analog Controller
+	 * Other features:
+	 * - LED-indicated digital "ANALOG" button at south part of center position
+	 *   for toggling between analogue and digital mode
+	 *   (TODO What does digital mode on Dual Analog do?)
 	 */
 	LIBGAMEPAD_CONTROLLER_DUAL_ANALOG,
 
@@ -885,7 +981,7 @@ enum libgamepad_game_controller {
 	 *     Digital "MODE" button right index finger position
 	 *     Digital "START" (shape: horizontal line) button at centre position
 	 * 
-	 * Conforming platforms:
+	 * Conforming controllers:
 	 * - Sega Nomad (however "MODE" is east of "START" which is far south east of "A")
 	 */
 	LIBGAMEPAD_CONTROLLER_6_BUTTON_ARCADE_PAD,
@@ -973,7 +1069,7 @@ enum libgamepad_game_controller {
 	 *     - West = "SELECT"
 	 *     - East = "START"
 	 * 
-	 * Conforming platforms:
+	 * Conforming controllers:
 	 * - Nintendo Game Boy
 	 * - Supervision (however "START" is also labelled "PAUSE" and the "SELECT" and "START"
 	 *                buttons are horizontal and north (slightly east) for "A" and "B" which
@@ -1040,7 +1136,7 @@ enum libgamepad_game_controller {
 	 *     Digital "L" button at left index finger position
 	 *     Digital "R" button at right index finger position
 	 *
-	 * Conforming platforms:
+	 * Conforming controllers:
 	 * - Game King (however "SELECT" and "START" are north of D-pad,
 	 *              "SELECT" to east and "START to west)
 	 */
@@ -1100,7 +1196,10 @@ enum libgamepad_game_controller {
 	 * BTN_EAST if there are 2 action buttons but reversed if there are 3
 	 * action buttons: (from bottom up) BTN_EAST, BTN_SOUTH, BTN_WEST
 	 * (`LIBGAMEPAD_CONTROLLER_LINUX_4_12_RECTIFIED_3BTN` is added to deal
-	 * with this problem).
+	 * with this problem). In the event that a controller has only one
+	 * action button (and truly is a gamepad and not a joystick), it shall
+	 * be reported as BTN_SOUTH as this one is designated as mandatory
+	 * (BTN_GAMEPAD) is an alias of it.
 	 */
 	LIBGAMEPAD_CONTROLLER_LINUX_4_12,
 
@@ -1383,18 +1482,18 @@ struct libgamepad_device {
 	/**
 	 * Human-readable device (sub- or superdevice) name
 	 */
-	const char *name;
+	char *name;
 
 	/**
 	 * ID that is supposted to be unique to the device
 	 * (sub- or superdevice)
 	 */
-	const char *unique_id;
+	char *unique_id;
 
 	/**
 	 * The location if the device
 	 */
-	const char *physical_location;
+	char *physical_location;
 
 	/**
 	 * Number of (digital) buttons/keys present
@@ -1452,6 +1551,18 @@ struct libgamepad_device {
 	 * Bitmap of supported force feedback effects
 	 */
 	uint8_t force_feedback_support[(FF_CNT + 7) / 8];
+
+	/**
+	 * Device fingerprint that does not take `.unique_id`
+	 * into account
+	 */
+	char fingerprint[65];
+
+	/**
+	 * Device fingerprint that does take `.unique_id`
+	 * into account
+	 */
+	char fingerprint_unique[65];
 };
 
 
@@ -1697,6 +1808,15 @@ int16_t libgamepad_get_relative_axis_by_name(const char *);
 /**
  * Get whether a button/key is pressed down or not
  * 
+ * libgamepad caches the last read button/key state,
+ * and will return the cached .state The underlaying
+ * ioctl(3) will has the ability to read a state
+ * even when the device is grabbed, but even if the
+ * device is not grabbed, the state may be out of
+ * that. Because the state may be out of date,
+ * libgamepad reads the current state when a device
+ * is opened.
+ * 
  * @param   device  The device to retrieve the information for
  * @param   code    The button/key
  * @return          1 if the button/key is pressed down,
@@ -1707,11 +1827,20 @@ int libgamepad_get_button_is_pressed(struct libgamepad_device *, uint16_t);
 /**
  * Get information about an absolute axis
  * 
+ * libgamepad caches the last read axis value, and
+ * will return the cached value. The underlaying
+ * ioctl(3) will has the ability to read a value
+ * even when the device is grabbed, but even if the
+ * device is not grabbed, the value may be out of
+ * that. Because the value may be out of date,
+ * libgamepad reads the current state when a device
+ * is opened.
+ * 
  * @param   device  The device to retrieve the information for
  * @param   code    The axis
  * @return          Information about the axis
  */
-const struct input_absinfo *libgamepad_get_absolute_axis_info(struct libgamepad_device *, uint16_t);
+LIBGAMEPAD_PURE__ const struct input_absinfo *libgamepad_get_absolute_axis_info(struct libgamepad_device *, uint16_t);
 /* `struct input_absinfo` is defined in <linux/input.h> */
 
 
diff --git a/libgamepad_close_device.c b/libgamepad_close_device.c
index 3b00149..273c7f8 100644
--- a/libgamepad_close_device.c
+++ b/libgamepad_close_device.c
@@ -11,14 +11,22 @@ libgamepad_close_device(struct libgamepad_device *device)
 				close(device->fd);
 			if (device->internals->dev)
 				libevdev_free(device->internals->dev);
+			free(device->internals->absinfo);
+			free(device->internals->buttons);
 			free(device->internals);
 			device->internals = NULL;
 		}
 		free(device->buttons);
 		free(device->absolute_axes);
 		free(device->relative_axes);
+		free(device->name);
+		free(device->unique_id);
+		free(device->physical_location);
 		device->buttons = NULL;
 		device->absolute_axes = NULL;
 		device->relative_axes = NULL;
+		device->name = NULL;
+		device->unique_id = NULL;
+		device->physical_location = NULL;
 	}
 }
diff --git a/libgamepad_get_absolute_axis_info.c b/libgamepad_get_absolute_axis_info.c
index a5aa4d5..ebd38fd 100644
--- a/libgamepad_get_absolute_axis_info.c
+++ b/libgamepad_get_absolute_axis_info.c
@@ -5,5 +5,7 @@
 const struct input_absinfo *
 libgamepad_get_absolute_axis_info(struct libgamepad_device *device, uint16_t code)
 {
-	return libevdev_get_abs_info(device->internals->dev, (unsigned int)code);
+	if ((size_t)code >= ELEMSOF(device->absolute_axis_map) || device->absolute_axis_map[code] == -1)
+		return NULL;
+	return &device->internals->absinfo[device->absolute_axis_map[code]];
 }
diff --git a/libgamepad_get_button_is_pressed.c b/libgamepad_get_button_is_pressed.c
index e3c0265..3c545c1 100644
--- a/libgamepad_get_button_is_pressed.c
+++ b/libgamepad_get_button_is_pressed.c
@@ -2,8 +2,17 @@
 #include "common.h"
 
 
+#if defined(__GNUC__)
+# pragma GCC diagnostic ignored "-Wsuggest-attribute=pure"
+#endif
+
+
 int
 libgamepad_get_button_is_pressed(struct libgamepad_device *device, uint16_t code)
 {
-	return libevdev_get_event_value(device->internals->dev, EV_KEY, (unsigned int)code);
+	int16_t i;
+	if ((size_t)code >= ELEMSOF(device->button_map))
+		return 0;
+	i = device->button_map[code];
+	return i >= 0 && (int)GETBIT(device->internals->buttons, (uint16_t)i);
 }
diff --git a/libgamepad_open_device.c b/libgamepad_open_device.c
index 3c2a751..22163a4 100644
--- a/libgamepad_open_device.c
+++ b/libgamepad_open_device.c
@@ -1,39 +1,165 @@
 /* See LICENSE file for copyright and license details. */
 #include "common.h"
 
+#define ELEMS_REQUIRED(BITS, TYPE) ((BITS + BITSOF(TYPE) - 1) / BITSOF(TYPE))
+#define MAX2(A, B) ((A) > (B) ? (A) : (B))
+#define MAX4(A, B, C, D) (MAX2(MAX2(A, B), MAX2(C, D)))
+
+
+static void
+store_uint(uint64_t value, char *buf)
+{
+	buf[0] = (char)((value >> 0) & 255);
+	buf[1] = (char)((value >> 8) & 255);
+	buf[2] = (char)((value >> 16) & 255);
+	buf[3] = (char)((value >> 24) & 255);
+	buf[4] = (char)((value >> 32) & 255);
+	buf[5] = (char)((value >> 40) & 255);
+	buf[6] = (char)((value >> 48) & 255);
+	buf[7] = (char)((value >> 56) & 255);
+}
+
+
+LIBGAMEPAD_CONST__
+static size_t
+popcount(uint8_t value)
+{
+	size_t n = 0;
+	for (; value; value >>= 1)
+		if (value & 1)
+			n += 1;
+	return n;
+}
+
+
+static int
+get_fingerprint(struct libgamepad_device *device, char non_unique[65], char unique[65])
+{
+	struct libsha2_state s, s2;
+	char buf[128];
+	size_t i, n;
+
+	if (libsha2_init(&s, LIBSHA2_256))
+		return -1;
+
+	libsha2_update(&s, device->name, 8 * strlen(device->name) + 8);
+	libsha2_update(&s, device->physical_location, 8 * strlen(device->physical_location) + 8);
+
+	store_uint(device->vendor, &buf[0]);
+	store_uint(device->product, &buf[8]);
+	store_uint(device->version, &buf[16]);
+	libsha2_update(&s, buf, 3 * 64);
+
+	store_uint(device->nbuttons, buf);
+	for (n = 8, i = 0; i < ELEMSOF(device->button_map); i++) {
+		if (device->button_map[i] >= 0) {
+			store_uint((uint64_t)i, &buf[n]);
+			n += 8;
+			if (n == sizeof(buf)) {
+				libsha2_update(&s, buf, 8 * n);
+				n = 0;
+			}
+		}
+	}
+	libsha2_update(&s, buf, 8 * n);
+	n = 0;
+
+	store_uint(device->nabsolute_axes, buf);
+	for (n = 8, i = 0; i < ELEMSOF(device->absolute_axis_map); i++) {
+		if (device->absolute_axis_map[i] >= 0) {
+			store_uint((uint64_t)i, &buf[n]);
+			n += 8;
+			if (n == sizeof(buf)) {
+				libsha2_update(&s, buf, 8 * n);
+				n = 0;
+			}
+		}
+	}
+	libsha2_update(&s, buf, 8 * n);
+	n = 0;
+
+	store_uint(device->nrelative_axes, buf);
+	for (n = 8, i = 0; i < ELEMSOF(device->relative_axis_map); i++) {
+		if (device->relative_axis_map[i] >= 0) {
+			store_uint((uint64_t)i, &buf[n]);
+			n += 8;
+			if (n == sizeof(buf)) {
+				libsha2_update(&s, buf, 8 * n);
+				n = 0;
+			}
+		}
+	}
+	libsha2_update(&s, buf, 8 * n);
+	n = 0;
+
+	n = 0;
+	for (i = 0; i < ELEMSOF(device->force_feedback_support); i++)
+		if (device->force_feedback_support[i])
+			n += popcount(device->force_feedback_support[i]);
+	store_uint((uint64_t)n, buf);
+	for (n = 8, i = 0; i < BITSOF(device->force_feedback_support); i++) {
+		if (GETBIT(device->force_feedback_support, i)) {
+			store_uint((uint64_t)i, &buf[n]);
+			n += 8;
+			if (n == sizeof(buf)) {
+				libsha2_update(&s, buf, 8 * n);
+				n = 0;
+			}
+		}
+	}
+	libsha2_update(&s, buf, 8 * n);
+	n = 0;
+
+	memcpy(&s2, &s, sizeof(s));
+	libsha2_update(&s2, device->unique_id, 8 * strlen(device->unique_id) + 8);
+
+	libsha2_digest(&s, NULL, 0, buf);
+	libsha2_behex_lower(non_unique, buf, 32);
+	libsha2_digest(&s2, NULL, 0, buf);
+	libsha2_behex_lower(unique, buf, 32);
+	return 0;
+}
+
 
 int
 libgamepad_open_device(struct libgamepad_device *devicep, int dirfd, const char *path, int mode)
 {
-	int err;
-	unsigned int i;
+	unsigned long int bits[ELEMS_REQUIRED(MAX4(ELEMSOF(devicep->button_map),
+	                                           ELEMSOF(devicep->absolute_axis_map),
+	                                           ELEMSOF(devicep->relative_axis_map),
+	                                           ELEMSOF(devicep->force_feedback_support)), long int)];
+	int err, r;
+	int16_t j;
 	uint16_t n;
+	unsigned int i, max;
 	struct input_id id;
+	char *buf = NULL;
+	size_t bufsize = 0;
+	void *new;
 
+	memset(devicep, 0, sizeof(*devicep));
 	devicep->fd = dirfd;
-	devicep->internals = NULL;
-	devicep->buttons = NULL;
-	devicep->absolute_axes = NULL;
-	devicep->relative_axes = NULL;
-	memset(devicep->force_feedback_support, 0, sizeof(devicep->force_feedback_support));
 
 	devicep->internals = calloc(1, sizeof(*devicep->internals));
 	if (!devicep->internals)
 		return -1;
 
+
 	if (path && *path) {
 		devicep->fd = openat(dirfd, path, mode);
-		if (devicep->fd < 0) {
-			libgamepad_close_device(devicep);
-			return -1;
-		}
+		if (devicep->fd < 0)
+			goto fail;
 		devicep->internals->close_fd = 1;
 	}
 
-	if (ioctl(devicep->fd, EVIOCGID, &id)) {
-		libgamepad_close_device(devicep);
-		return -1;
-	}
+
+	if (ioctl(devicep->fd, EVIOCGID, &id) < 0)
+		goto fail;
+	devicep->bus_type = (unsigned int)id.bustype;
+	devicep->vendor   = (unsigned int)id.vendor;
+	devicep->product  = (unsigned int)id.product;
+	devicep->version  = (unsigned int)id.version;
+
 
 	err = libevdev_new_from_fd(devicep->fd, &devicep->internals->dev);
 	if (err < 0) {
@@ -42,68 +168,105 @@ libgamepad_open_device(struct libgamepad_device *devicep, int dirfd, const char
 		return -1;
 	}
 
-	devicep->name              = libevdev_get_name(devicep->internals->dev);
-	devicep->unique_id         = libevdev_get_uniq(devicep->internals->dev);
-	devicep->physical_location = libevdev_get_phys(devicep->internals->dev);
-	devicep->bus_type          = (unsigned int)id.bustype;
-	devicep->vendor            = (unsigned int)id.vendor;
-	devicep->product           = (unsigned int)id.product;
-	devicep->version           = (unsigned int)id.version;
-
-	devicep->nbuttons = 0;
-	for (i = 0; i < KEY_CNT; i++) {
-		devicep->button_map[i] = -1;
-		if (libevdev_has_event_code(devicep->internals->dev, EV_KEY, i))
-			devicep->button_map[i] = (int16_t)devicep->nbuttons++;
-	}
 
-	devicep->nabsolute_axes = 0;
-	for (i = 0; i < ABS_CNT; i++) {
-		devicep->absolute_axis_map[i] = -1;
-		if (libevdev_has_event_code(devicep->internals->dev, EV_ABS, i))
-			devicep->absolute_axis_map[i] = (int16_t)devicep->nabsolute_axes++;
-	}
+#define GET_STRING(EVIOCMACRO, OUTPUT)\
+	do {\
+		for (;;) {\
+			r = ioctl(devicep->fd, EVIOCMACRO(bufsize), buf);\
+			if (r < 0)\
+				goto fail_free_buf;\
+			if ((size_t)r < bufsize)\
+				break;\
+			new = realloc(buf, bufsize += 32);\
+			if (!new)\
+				goto fail_free_buf;\
+			buf = new;\
+		}\
+		buf[r] = '\0';\
+		*OUTPUT = strdup(buf);\
+		if (!*OUTPUT)\
+			goto fail_free_buf;\
+	} while (0)
+	GET_STRING(EVIOCGNAME, &devicep->name);
+	GET_STRING(EVIOCGUNIQ, &devicep->unique_id);
+	GET_STRING(EVIOCGPHYS, &devicep->physical_location);
+	free(buf);
 
-	devicep->nrelative_axes = 0;
-	for (i = 0; i < REL_CNT; i++) {
-		devicep->relative_axis_map[i] = -1;
-		if (libevdev_has_event_code(devicep->internals->dev, EV_REL, i))
-			devicep->relative_axis_map[i] = (int16_t)devicep->nrelative_axes++;
-	}
 
-	for (i = 0; i < FF_CNT; i++)
-		if (libevdev_has_event_code(devicep->internals->dev, EV_FF, i))
-			devicep->force_feedback_support[i / 8] |= (uint8_t)(1 << (i & 7));
+#define CREATE_MAPS(EVENTS, SINGULAR, PLURAL)\
+	do {\
+		/* Code-to-index map */\
+		r = ioctl(devicep->fd, EVIOCGBIT(EVENTS, sizeof(bits)), bits);\
+		if (r < 0)\
+			goto fail;\
+		max = (unsigned int)r * 8;\
+		devicep->n##PLURAL = 0;\
+		for (i = 0; i < ELEMSOF(devicep->SINGULAR##_map); i++) {\
+			devicep->SINGULAR##_map[i] = -1;\
+			if (i < max && ((bits[i / BITSOF(*bits)] >> (i % BITSOF(*bits))) & 1))\
+				devicep->SINGULAR##_map[i] = (int16_t)devicep->n##PLURAL++;\
+		}\
+		\
+		/* Index-to-code map */\
+		if (devicep->n##PLURAL) {\
+			devicep->PLURAL = calloc(devicep->n##PLURAL, sizeof(*devicep->PLURAL));\
+			if (!devicep->PLURAL)\
+				goto fail;\
+			for (i = 0, n = 0; i < ELEMSOF(devicep->SINGULAR##_map); i++)\
+				if (devicep->SINGULAR##_map[i] >= 0)\
+					devicep->PLURAL[n++] = (uint16_t)i;\
+		}\
+	} while (0)
+
+	CREATE_MAPS(EV_KEY, button, buttons);
+	CREATE_MAPS(EV_ABS, absolute_axis, absolute_axes);
+	CREATE_MAPS(EV_REL, relative_axis, relative_axes);
 
-	if (devicep->nbuttons) {
-		devicep->buttons = calloc(devicep->nbuttons, sizeof(*devicep->buttons));
-		if (!devicep->buttons)
-			goto fail;
-		for (i = 0, n = 0; i < KEY_CNT; i++)
-			if (devicep->button_map[i] >= 0)
-				devicep->buttons[n++] = (uint16_t)i;
-	}
 
 	if (devicep->nabsolute_axes) {
-		devicep->absolute_axes = calloc(devicep->nabsolute_axes, sizeof(*devicep->absolute_axes));
-		if (!devicep->absolute_axes)
+		devicep->internals->absinfo = calloc(devicep->nabsolute_axes, sizeof(*devicep->internals->absinfo));
+		if (!devicep->internals->absinfo)
 			goto fail;
-		for (i = 0, n = 0; i < ABS_CNT; i++)
-			if (devicep->absolute_axis_map[i] >= 0)
-				devicep->absolute_axes[n++] = (uint16_t)i;
 	}
+	for (i = 0; i < devicep->nabsolute_axes; i++)
+		if (ioctl(devicep->fd, EVIOCGABS((unsigned int)devicep->absolute_axes[i]), &devicep->internals->absinfo[i]) < 0)
+			goto fail;
+
 
-	if (devicep->nrelative_axes) {
-		devicep->relative_axes = calloc(devicep->nrelative_axes, sizeof(*devicep->relative_axes));
-		if (!devicep->relative_axes)
+	if (devicep->nbuttons) {
+		devicep->internals->buttons = calloc((devicep->nbuttons + 7) / 8, sizeof(*devicep->internals->buttons));
+		if (!devicep->internals->buttons)
 			goto fail;
-		for (i = 0, n = 0; i < REL_CNT; i++)
-			if (devicep->relative_axis_map[i] >= 0)
-				devicep->relative_axes[n++] = (uint16_t)i;
+		r = ioctl(devicep->fd, EVIOCGKEY(sizeof(bits)), bits);
+		if (r < 0)
+			goto fail;
+		max = (unsigned int)r * 8;
+		for (i = 0; i < max && i < ELEMSOF(devicep->button_map); i++) {
+			j = devicep->button_map[i];
+			if (j >= 0 && GETBIT(bits, i))
+				SETBIT(devicep->internals->buttons, (uint16_t)j);
+		}
 	}
 
+
+	r = ioctl(devicep->fd, EVIOCGBIT(EV_FF, sizeof(bits)), bits);
+	if (r < 0)
+		goto fail;
+	max = (unsigned int)r * 8;
+	for (i = 0; i < BITSOF(devicep->force_feedback_support); i++)
+		if (i < max && ((bits[i / BITSOF(*bits)] >> (i % BITSOF(*bits))) & 1))
+			SETBIT(devicep->force_feedback_support, i);
+
+
+	if (get_fingerprint(devicep, devicep->fingerprint, devicep->fingerprint_unique))
+		goto fail;
+
+	/* TODO get actual KEY/ABS state */
+
 	return 0;
 
+fail_free_buf:
+	free(buf);
 fail:
 	libgamepad_close_device(devicep);
 	return -1;
diff --git a/test-details.c b/test-details.c
index e834819..f8b2365 100644
--- a/test-details.c
+++ b/test-details.c
@@ -31,6 +31,8 @@ main(int argc, char *argv[])
 	printf("Name: %s\n", gamepad.name);
 	printf("Unique id: %s\n", gamepad.unique_id);
 	printf("Physical location: %s\n", gamepad.physical_location);
+	printf("Fingerprint: %s\n", gamepad.fingerprint);
+	printf("Unique fingerprint: %s\n", gamepad.fingerprint_unique);
 
 	printf("Buttons:\n");
 	for (i = 0; i < gamepad.nbuttons; i++) {