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 <string.h>
   9 #include <sysexits.h>
  10 #include <sys/select.h>
  11 #include <unistd.h>
  12
  13 int main (int argc, char **argv)
  14 {
  15   int print_usec = 0;
  16   char* device = strdup("/dev/input/by-path/*kbd*");
  17   struct option long_options[] = {
  18     {"device", required_argument, 0,            'd' },
  19     {"usec",   no_argument,       &print_usec,  1   },
  20     {0,        0,                 0,            0   },
  21   };
  22   while (1) {
  23     int c = getopt_long(argc, argv, "", long_options, NULL);
  24     if (c == -1) break;
  25     if (c == 'd') {
  26       free(device);
  27       device = strdup(optarg);
  28       continue;
  29     }
  30     if (c != 0) exit(EX_USAGE);
  31   }
  32
  33   fd_set all_inputs;
  34   FD_ZERO(&all_inputs);
  35   int maxfd = 0;
  36   glob_t glob_result;
  37   int glob_return = glob(device, GLOB_ERR | GLOB_NOSORT, NULL, &glob_result);
  38   if (glob_return == GLOB_NOMATCH) {
  39     errx(EX_NOINPUT, "Could not find keyboard event file(s): %s", device);
  40   }
  41   if (glob_return != 0) {
  42     err(EX_NOINPUT, "Could not glob keyboard event file(s): %s", device);
  43   }
  44   free(device);
  45   for (unsigned i = 0; i < glob_result.gl_pathc; i++) {
  46     int open_fd = open(glob_result.gl_pathv[i], O_RDONLY);
  47     if (open_fd < 0) {
  48       err(EX_NOINPUT, "Could not open keyboard event file: %s", glob_result.gl_pathv[i]);
  49     }
  50     if (open_fd > maxfd) {
  51       maxfd = open_fd;
  52     }
  53     FD_SET(open_fd, &all_inputs);
  54   }
  55   globfree(&glob_result);
  56
  57   struct input_event i;
  58   while (1) {
  59     fd_set ready_inputs = all_inputs;
  60     if (select(maxfd+1, &ready_inputs, NULL, NULL, NULL) != 1) {
  61       err(EX_IOERR, "select");
  62     }
  63     for (int fd=0; fd <= maxfd; fd++) {
  64       if (FD_ISSET(fd, &ready_inputs)) {
  65         int read_return = read(fd, &i, sizeof(i));
  66         if (read_return == -1) {
  67           err(EX_IOERR, "read");
  68         }
  69         if (read_return != sizeof(i)) {
  70           errx(EX_IOERR, "Unexpected EOF");
  71         }
  72         if (i.type == 1 && i.value == 1) {
  73           if (print_usec) {
  74             printf("%ld.%06ld\n", i.time.tv_sec, i.time.tv_usec);
  75           } else {
  76             printf("%ld\n", i.time.tv_sec);
  77           }
  78           fflush(stdout);
  79         }
  80       }
  81     }
  82   }
  83   return 0;
  84 }