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   FILE *output_file;
  38   if (output == NULL) {
  39     output_file = stdout;
  40   } else {
  41     output_file = fopen(output, "a");
  42     if (output_file == NULL) {
  43       err(EX_CANTCREAT, "Could not open output file: %s", output);
  44     }
  45   }
  46
  47   fd_set all_inputs;
  48   FD_ZERO(&all_inputs);
  49   int maxfd = 0;
  50   glob_t glob_result;
  51   int glob_return = glob(device, GLOB_ERR | GLOB_NOSORT, NULL, &glob_result);
  52   if (glob_return == GLOB_NOMATCH) {
  53     errx(EX_NOINPUT, "Could not find keyboard event file(s): %s", device);
  54   }
  55   if (glob_return != 0) {
  56     err(EX_NOINPUT, "Could not glob keyboard event file(s): %s", device);
  57   }
  58   for (unsigned i = 0; i < glob_result.gl_pathc; i++) {
  59     int device_fd = open(glob_result.gl_pathv[i], O_RDONLY);
  60     if (device_fd < 0) {
  61       err(EX_NOINPUT, "Could not open keyboard event file: %s", glob_result.gl_pathv[i]);
  62     }
  63     if (device_fd > maxfd) {
  64       maxfd = device_fd;
  65     }
  66     FD_SET(device_fd, &all_inputs);
  67   }
  68   globfree(&glob_result);
  69
  70   struct input_event i;
  71   while (1) {
  72     fd_set ready_inputs = all_inputs;
  73     if (select(maxfd+1, &ready_inputs, NULL, NULL, NULL) != 1) {
  74       err(EX_IOERR, "select");
  75     }
  76     for (int fd=0; fd <= maxfd; fd++) {
  77       if (FD_ISSET(fd, &ready_inputs)) {
  78         int read_return = read(fd, &i, sizeof(i));
  79         if (read_return == -1) {
  80           err(EX_IOERR, "read");
  81         }
  82         if (read_return != sizeof(i)) {
  83           errx(EX_IOERR, "Unexpected EOF");
  84         }
  85         if (i.type == 1 && i.value == 1) {
  86           if (print_usec) {
  87             fprintf(output_file, "%ld.%06ld\n", i.time.tv_sec, i.time.tv_usec);
  88           } else {
  89             fprintf(output_file, "%ld\n", i.time.tv_sec);
  90           }
  91           fflush(output_file);
  92         }
  93       }
  94     }
  95   }
  96   return 0;
  97 }