git.scottworley.com Git - keystroke-timestamps/blob - keystroke-timestamps.c

   1 #include <err.h>
   2 #include <fcntl.h>
   3 #include <glob.h>
   4 #include <getopt.h>
   5 #include <linux/input.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <sysexits.h>
   9 #include <sys/select.h>
  10 #include <unistd.h>
  11
  12 int main (int argc, char **argv)
  13 {
  14   int print_usec = 0;
  15   char* device = "/dev/input/by-path/*kbd*";
  16   struct option long_options[] = {
  17     {"device", required_argument, 0,            'd' },
  18     {"usec",   no_argument,       &print_usec,  1   },
  19     {0,        0,                 0,            0   },
  20   };
  21   while (1) {
  22     int c = getopt_long(argc, argv, "", long_options, NULL);
  23     if (c == -1) break;
  24     if (c == 'd') {
  25       device = optarg;
  26       continue;
  27     }
  28     if (c != 0) exit(EX_USAGE);
  29   }
  30
  31   fd_set all_inputs;
  32   FD_ZERO(&all_inputs);
  33   int maxfd = 0;
  34   glob_t glob_result;
  35   int glob_return = glob(device, GLOB_ERR | GLOB_NOSORT, NULL, &glob_result);
  36   if (glob_return == GLOB_NOMATCH) {
  37     errx(EX_NOINPUT, "Could not find keyboard event file(s): %s", device);
  38   }
  39   if (glob_return != 0) {
  40     err(EX_NOINPUT, "Could not glob keyboard event file(s): %s", device);
  41   }
  42   for (unsigned i = 0; i < glob_result.gl_pathc; i++) {
  43     int open_fd = open(glob_result.gl_pathv[i], O_RDONLY);
  44     if (open_fd < 0) {
  45       err(EX_NOINPUT, "Could not open keyboard event file: %s", glob_result.gl_pathv[i]);
  46     }
  47     if (open_fd > maxfd) {
  48       maxfd = open_fd;
  49     }
  50     FD_SET(open_fd, &all_inputs);
  51   }
  52   globfree(&glob_result);
  53
  54   struct input_event i;
  55   while (1) {
  56     fd_set ready_inputs = all_inputs;
  57     if (select(maxfd+1, &ready_inputs, NULL, NULL, NULL) != 1) {
  58       err(EX_IOERR, "select");
  59     }
  60     for (int fd=0; fd <= maxfd; fd++) {
  61       if (FD_ISSET(fd, &ready_inputs)) {
  62         int read_return = read(fd, &i, sizeof(i));
  63         if (read_return == -1) {
  64           err(EX_IOERR, "read");
  65         }
  66         if (read_return != sizeof(i)) {
  67           errx(EX_IOERR, "Unexpected EOF");
  68         }
  69         if (i.type == 1 && i.value == 1) {
  70           if (print_usec) {
  71             printf("%ld.%06ld\n", i.time.tv_sec, i.time.tv_usec);
  72           } else {
  73             printf("%ld\n", i.time.tv_sec);
  74           }
  75           fflush(stdout);
  76         }
  77       }
  78     }
  79   }
  80   return 0;
  81 }