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   char* output = NULL;
  17   struct option long_options[] = {
  18     {"device", required_argument, 0,            'd' },
  19     {"output", required_argument, 0,            'o' },
  20     {"usec",   no_argument,       &print_usec,  1   },
  21     {0,        0,                 0,            0   },
  22   };
  23   while (1) {
  24     int c = getopt_long(argc, argv, "", long_options, NULL);
  25     if (c == -1) break;
  26     if (c == 'd') {
  27       device = optarg;
  28       continue;
  29     }
  30     if (c == 'o') {
  31       output = optarg;
  32       continue;
  33     }
  34     if (c != 0) exit(EX_USAGE);
  35   }
  36
  37   /* Open output file */
  38   FILE *output_file;
  39   if (output == NULL) {
  40     output_file = stdout;
  41   } else {
  42     output_file = fopen(output, "a");
  43     if (output_file == NULL) {
  44       err(EX_CANTCREAT, "Could not open output file: %s", output);
  45     }
  46   }
  47
  48   /* Open device inputs */
  49   fd_set all_inputs;
  50   FD_ZERO(&all_inputs);
  51   int maxfd = 0;
  52   glob_t glob_result;
  53   int glob_return = glob(device, GLOB_ERR | GLOB_NOSORT, NULL, &glob_result);
  54   if (glob_return == GLOB_NOMATCH) {
  55     errx(EX_NOINPUT, "Could not find keyboard event file(s): %s", device);
  56   }
  57   if (glob_return != 0) {
  58     err(EX_NOINPUT, "Could not glob keyboard event file(s): %s", device);
  59   }
  60   for (unsigned i = 0; i < glob_result.gl_pathc; i++) {
  61     int device_fd = open(glob_result.gl_pathv[i], O_RDONLY);
  62     if (device_fd < 0) {
  63       err(EX_NOINPUT, "Could not open keyboard event file: %s", glob_result.gl_pathv[i]);
  64     }
  65     if (device_fd > maxfd) {
  66       maxfd = device_fd;
  67     }
  68     FD_SET(device_fd, &all_inputs);
  69   }
  70   globfree(&glob_result);
  71
  72   /* Report keystroke timestamps */
  73   struct input_event i;
  74   while (1) {
  75     fd_set ready_inputs = all_inputs;
  76     if (select(maxfd+1, &ready_inputs, NULL, NULL, NULL) != 1) {
  77       err(EX_IOERR, "select");
  78     }
  79     for (int fd=0; fd <= maxfd; fd++) {
  80       if (FD_ISSET(fd, &ready_inputs)) {
  81         int read_return = read(fd, &i, sizeof(i));
  82         if (read_return == -1) {
  83           err(EX_IOERR, "read");
  84         }
  85         if (read_return != sizeof(i)) {
  86           errx(EX_IOERR, "Unexpected EOF");
  87         }
  88         if (i.type == 1 && i.value == 1) {
  89           if (print_usec) {
  90             fprintf(output_file, "%ld.%06ld\n", i.time.tv_sec, i.time.tv_usec);
  91           } else {
  92             fprintf(output_file, "%ld\n", i.time.tv_sec);
  93           }
  94           fflush(output_file);
  95         }
  96       }
  97     }
  98   }
  99   return 0;
 100 }