Libinput sample

The libinput API documentation has a sample program on the main page but it doesn't compile as given.

This revision of it does compile and run:

#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <libinput.h>
#include <libudev.h>
#include <stdio.h>

#define ANSI_HIGHLIGHT    "\x1B[0;1;39m"
#define ANSI_RED    "\x1B[0;31m"
#define ANSI_GREEN    "\x1B[0;32m"
#define ANSI_YELLOW   "\x1B[0;33m"
#define ANSI_BLUE   "\x1B[0;34m"
#define ANSI_MAGENTA    "\x1B[0;35m"
#define ANSI_CYAN   "\x1B[0;36m"
#define ANSI_BRIGHT_RED   "\x1B[0;31;1m"
#define ANSI_BRIGHT_GREEN "\x1B[0;32;1m"
#define ANSI_BRIGHT_YELLOW  "\x1B[0;33;1m"
#define ANSI_BRIGHT_BLUE  "\x1B[0;34;1m"
#define ANSI_BRIGHT_MAGENTA "\x1B[0;35;1m"
#define ANSI_BRIGHT_CYAN  "\x1B[0;36;1m"
#define ANSI_NORMAL   "\x1B[0m"


static int open_restricted(const char *path, int flags, void *user_data)
{
        int fd = open(path, flags);
        return fd < 0 ? -errno : fd;
}
 
static void close_restricted(int fd, void *user_data)
{
        close(fd);
}
 
const static struct libinput_interface interface = {
        .open_restricted = open_restricted,
        .close_restricted = close_restricted,
};

static void
log_handler(struct libinput *li,
    enum libinput_log_priority priority,
    const char *format,
    va_list args)
{
  static int is_tty = -1;

  if (is_tty == -1)
    is_tty = isatty(STDOUT_FILENO);

  if (is_tty) {
    if (priority >= LIBINPUT_LOG_PRIORITY_ERROR)
      printf(ANSI_RED);
    else if (priority >= LIBINPUT_LOG_PRIORITY_INFO)
      printf(ANSI_HIGHLIGHT);
  }

  vprintf(format, args);

  if (is_tty && priority >= LIBINPUT_LOG_PRIORITY_INFO)
    printf(ANSI_NORMAL);
}
 
 
int main(void) {
  fprintf(stderr, "start main\n");
        struct libinput *li;
        struct libinput_event *event;

        struct udev *udev = udev_new();

        if (!udev) {
          fprintf(stderr, "Failed to initialize udev\n");
          return -1;
        }
 
        fprintf(stderr, "create libinput context for udev\n");
        li = libinput_udev_create_context(&interface, NULL, udev);
        if (!li) {
          fprintf(stderr, "Failed to create libinput context\n");
          return -1;
        }

        libinput_log_set_handler(li, log_handler);
        libinput_log_set_priority(li, LIBINPUT_LOG_PRIORITY_DEBUG);

        if (libinput_udev_assign_seat(li, "seat0")) {
          fprintf(stderr, "Failed to assign seat\n");
          libinput_unref(li);
          li = NULL;
          udev_unref(udev);
          return -1;
        }

        libinput_dispatch(li);
 
        while ((event = libinput_get_event(li)) != NULL) {
 
                // handle the event here
                fprintf(stderr, "in the event loop\n");
 
                libinput_event_destroy(event);
                libinput_dispatch(li);
        }
 
        fprintf(stderr, "unreference libinput context\n");
        libinput_unref(li);
 
        return 0;
}

 

This can be compiled with:

$  gcc -o sample sample.c `pkg-config --cflags --libs libinput` -ludev