udev-builtin-input_id.c revision 244477333afc8b95d2a5b2c05b7d8fe8b1be89c0
/*
* expose input properties via udev
*
* Copyright (C) 2009 Martin Pitt <martin.pitt@ubuntu.com>
* Portions Copyright (C) 2004 David Zeuthen, <david@fubar.dk>
* Copyright (C) 2011 Kay Sievers <kay@vrfy.org>
* Copyright (C) 2014 Carlos Garnacho <carlosg@gnome.org>
* Copyright (C) 2014 David Herrmann <dh.herrmann@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <linux/limits.h>
#include <linux/input.h>
#include "udev.h"
#include "util.h"
/* we must use this kernel-compatible implementation */
#define BITS_PER_LONG (sizeof(unsigned long) * 8)
#define NBITS(x) ((((x)-1)/BITS_PER_LONG)+1)
#define OFF(x) ((x)%BITS_PER_LONG)
#define BIT(x) (1UL<<OFF(x))
#define LONG(x) ((x)/BITS_PER_LONG)
#define test_bit(bit, array) ((array[LONG(bit)] >> OFF(bit)) & 1)
static inline int abs_size_mm(const struct input_absinfo *absinfo) {
/* Resolution is defined to be in units/mm for ABS_X/Y */
return (absinfo->maximum - absinfo->minimum) / absinfo->resolution;
}
static void extract_info(struct udev_device *dev, const char *devpath, bool test) {
char width[DECIMAL_STR_MAX(int)], height[DECIMAL_STR_MAX(int)];
struct input_absinfo xabsinfo = {}, yabsinfo = {};
_cleanup_close_ int fd = -1;
fd = open(devpath, O_RDONLY|O_CLOEXEC);
if (fd < 0)
return;
if (ioctl(fd, EVIOCGABS(ABS_X), &xabsinfo) < 0 ||
ioctl(fd, EVIOCGABS(ABS_Y), &yabsinfo) < 0)
return;
if (xabsinfo.resolution <= 0 || yabsinfo.resolution <= 0)
return;
snprintf(width, sizeof(width), "%d", abs_size_mm(&xabsinfo));
snprintf(height, sizeof(height), "%d", abs_size_mm(&yabsinfo));
udev_builtin_add_property(dev, test, "ID_INPUT_WIDTH_MM", width);
udev_builtin_add_property(dev, test, "ID_INPUT_HEIGHT_MM", height);
}
/*
* Read a capability attribute and return bitmask.
* @param dev udev_device
* @param attr sysfs attribute name (e. g. "capabilities/key")
* @param bitmask: Output array which has a sizeof of bitmask_size
*/
static void get_cap_mask(struct udev_device *dev,
struct udev_device *pdev, const char* attr,
unsigned long *bitmask, size_t bitmask_size,
bool test) {
const char *v;
char text[4096];
unsigned i;
char* word;
unsigned long val;
v = udev_device_get_sysattr_value(pdev, attr);
if (!v)
v = "";
snprintf(text, sizeof(text), "%s", v);
log_debug("%s raw kernel attribute: %s", attr, text);
memzero(bitmask, bitmask_size);
i = 0;
while ((word = strrchr(text, ' ')) != NULL) {
val = strtoul (word+1, NULL, 16);
if (i < bitmask_size/sizeof(unsigned long))
bitmask[i] = val;
else
log_debug("ignoring %s block %lX which is larger than maximum size", attr, val);
*word = '\0';
++i;
}
val = strtoul (text, NULL, 16);
if (i < bitmask_size / sizeof(unsigned long))
bitmask[i] = val;
else
log_debug("ignoring %s block %lX which is larger than maximum size", attr, val);
if (test) {
/* printf pattern with the right unsigned long number of hex chars */
snprintf(text, sizeof(text), " bit %%4u: %%0%zilX\n", 2 * sizeof(unsigned long));
log_debug("%s decoded bit map:", attr);
val = bitmask_size / sizeof (unsigned long);
/* skip over leading zeros */
while (bitmask[val-1] == 0 && val > 0)
--val;
for (i = 0; i < val; ++i) {
DISABLE_WARNING_FORMAT_NONLITERAL;
log_debug(text, i * BITS_PER_LONG, bitmask[i]);
REENABLE_WARNING;
}
}
}
/* pointer devices */
static void test_pointers (struct udev_device *dev,
const unsigned long* bitmask_ev,
const unsigned long* bitmask_abs,
const unsigned long* bitmask_key,
const unsigned long* bitmask_rel,
bool test) {
int is_mouse = 0;
int is_touchpad = 0;
if (!test_bit (EV_KEY, bitmask_ev)) {
if (test_bit (EV_ABS, bitmask_ev) &&
test_bit (ABS_X, bitmask_abs) &&
test_bit (ABS_Y, bitmask_abs) &&
test_bit (ABS_Z, bitmask_abs))
udev_builtin_add_property(dev, test, "ID_INPUT_ACCELEROMETER", "1");
return;
}
if (test_bit (EV_ABS, bitmask_ev) &&
test_bit (ABS_X, bitmask_abs) && test_bit (ABS_Y, bitmask_abs)) {
if (test_bit (BTN_STYLUS, bitmask_key) || test_bit (BTN_TOOL_PEN, bitmask_key))
udev_builtin_add_property(dev, test, "ID_INPUT_TABLET", "1");
else if (test_bit (BTN_TOOL_FINGER, bitmask_key) && !test_bit (BTN_TOOL_PEN, bitmask_key))
is_touchpad = 1;
else if (test_bit (BTN_MOUSE, bitmask_key))
/* This path is taken by VMware's USB mouse, which has
* absolute axes, but no touch/pressure button. */
is_mouse = 1;
else if (test_bit (BTN_TOUCH, bitmask_key))
udev_builtin_add_property(dev, test, "ID_INPUT_TOUCHSCREEN", "1");
/* joysticks don't necessarily have to have buttons; e. g.
* rudders/pedals are joystick-like, but buttonless; they have
* other fancy axes */
else if (test_bit (BTN_TRIGGER, bitmask_key) ||
test_bit (BTN_A, bitmask_key) ||
test_bit (BTN_1, bitmask_key) ||
test_bit (ABS_RX, bitmask_abs) ||
test_bit (ABS_RY, bitmask_abs) ||
test_bit (ABS_RZ, bitmask_abs) ||
test_bit (ABS_THROTTLE, bitmask_abs) ||
test_bit (ABS_RUDDER, bitmask_abs) ||
test_bit (ABS_WHEEL, bitmask_abs) ||
test_bit (ABS_GAS, bitmask_abs) ||
test_bit (ABS_BRAKE, bitmask_abs))
udev_builtin_add_property(dev, test, "ID_INPUT_JOYSTICK", "1");
}
if (test_bit (EV_REL, bitmask_ev) &&
test_bit (REL_X, bitmask_rel) && test_bit (REL_Y, bitmask_rel) &&
test_bit (BTN_MOUSE, bitmask_key))
is_mouse = 1;
if (is_mouse)
udev_builtin_add_property(dev, test, "ID_INPUT_MOUSE", "1");
if (is_touchpad)
udev_builtin_add_property(dev, test, "ID_INPUT_TOUCHPAD", "1");
}
/* key like devices */
static void test_key (struct udev_device *dev,
const unsigned long* bitmask_ev,
const unsigned long* bitmask_key,
bool test) {
unsigned i;
unsigned long found;
unsigned long mask;
/* do we have any KEY_* capability? */
if (!test_bit (EV_KEY, bitmask_ev)) {
log_debug("test_key: no EV_KEY capability");
return;
}
/* only consider KEY_* here, not BTN_* */
found = 0;
for (i = 0; i < BTN_MISC/BITS_PER_LONG; ++i) {
found |= bitmask_key[i];
log_debug("test_key: checking bit block %lu for any keys; found=%i", (unsigned long)i*BITS_PER_LONG, found > 0);
}
/* If there are no keys in the lower block, check the higher block */
if (!found) {
for (i = KEY_OK; i < BTN_TRIGGER_HAPPY; ++i) {
if (test_bit (i, bitmask_key)) {
log_debug("test_key: Found key %x in high block", i);
found = 1;
break;
}
}
}
if (found > 0)
udev_builtin_add_property(dev, test, "ID_INPUT_KEY", "1");
/* the first 32 bits are ESC, numbers, and Q to D; if we have all of
* those, consider it a full keyboard; do not test KEY_RESERVED, though */
mask = 0xFFFFFFFE;
if ((bitmask_key[0] & mask) == mask)
udev_builtin_add_property(dev, test, "ID_INPUT_KEYBOARD", "1");
}
static int builtin_input_id(struct udev_device *dev, int argc, char *argv[], bool test) {
struct udev_device *pdev;
unsigned long bitmask_ev[NBITS(EV_MAX)];
unsigned long bitmask_abs[NBITS(ABS_MAX)];
unsigned long bitmask_key[NBITS(KEY_MAX)];
unsigned long bitmask_rel[NBITS(REL_MAX)];
const char *sysname, *devnode;
/* walk up the parental chain until we find the real input device; the
* argument is very likely a subdevice of this, like eventN */
pdev = dev;
while (pdev != NULL && udev_device_get_sysattr_value(pdev, "capabilities/ev") == NULL)
pdev = udev_device_get_parent_with_subsystem_devtype(pdev, "input", NULL);
if (pdev) {
/* Use this as a flag that input devices were detected, so that this
* program doesn't need to be called more than once per device */
udev_builtin_add_property(dev, test, "ID_INPUT", "1");
get_cap_mask(dev, pdev, "capabilities/ev", bitmask_ev, sizeof(bitmask_ev), test);
get_cap_mask(dev, pdev, "capabilities/abs", bitmask_abs, sizeof(bitmask_abs), test);
get_cap_mask(dev, pdev, "capabilities/rel", bitmask_rel, sizeof(bitmask_rel), test);
get_cap_mask(dev, pdev, "capabilities/key", bitmask_key, sizeof(bitmask_key), test);
test_pointers(dev, bitmask_ev, bitmask_abs, bitmask_key, bitmask_rel, test);
test_key(dev, bitmask_ev, bitmask_key, test);
}
devnode = udev_device_get_devnode(dev);
sysname = udev_device_get_sysname(dev);
if (devnode && sysname && startswith(sysname, "event"))
extract_info(dev, devnode, test);
return EXIT_SUCCESS;
}
const struct udev_builtin udev_builtin_input_id = {
.name = "input_id",
.cmd = builtin_input_id,
.help = "Input device properties",
};