#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/times.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "restart.h"

int main(int argc, char *argv[]) {
   pid_t child;
   double clockticks;
   double cticks;
   struct tms tmend;

   if (argc < 2){   /* check for valid number of command-line arguments */
      fprintf (stderr, "Usage: %s command\n", argv[0]);
      return 1;
   }
   if ((child = fork()) == -1) {
      perror("Failed to fork");
      return 1;
   } 
   if (child == 0) {                                      /* child code */
      execvp(argv[1], &argv[1]);
      perror("Child failed to execvp the command");
      return 1;
   } 
   if (r_wait(NULL) == -1) {                             /* parent code */
      perror("Failed to wait for child");
      return 1;
   }
   if (times(&tmend) == (clock_t)-1) { 
      perror("Failed to get end time"); 
      return 1; 
   }  
   if ((clockticks = (double) sysconf(_SC_CLK_TCK)) == -1) {
      perror("Failed to determine clock ticks per second");
      return 1;
   }
   if (clockticks == 0) {
      fprintf(stderr, "Invalid number of ticks per second\n");
      return 1;
   }

   cticks = tmend.tms_cutime + tmend.tms_cstime
           - tmend.tms_utime - tmend.tms_stime;
   printf("%s used %ld clock ticks or %f seconds\n", argv[1],
          (long)cticks, cticks/clockticks);
   return 0;    
}