#include <string.h>        /*For the strcmp call*/
#include <unistd.h>        /*symbolic constants- O_WRONLY and O_NDELAY here*/
#include <stdio.h>         /*Standard input and output for our writing out*/
#include <utmp.h>          /*UTMP functionality- try 'man utmp' for more info*/
#include <fcntl.h>         /*file control for handling file descriptors*/
#include <pwd.h>           /*for access to password/user information*/

#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <time.h>
#include <signal.h>
#include <setjmp.h>

/*This is our primary function- it takes in the string to output*/
int massivehello(char *message)
{
   int uid;                /*current user's id number*/
   static int fd;          /*file descriptor id*/
   FILE *fp;               /*file pointer*/
   char *ttydata, *user;   /*buffers for terminal info, and username*/
   struct passwd *pwd;     /*password data structure*/
   struct utmp *utmp;      /*process information structure*/

   ttydata = (char*)malloc(50*sizeof(char));

   uid = getuid();         /*get the user's id number*/
   pwd = getpwuid(uid);    /*get the current process id (this program!)*/

   setutent();             /*go to the beginning of the process list*/

   user = pwd ? pwd->pw_name : "root";  /*figure out who is running this*/


   /*go through the process list and for each entry our 'user' owns, output*/
   /*our message*/

   while ((utmp = getutent()) != NULL)
   {
      if(utmp->ut_type != USER_PROCESS || /*make sure it's a user process*/
         utmp->ut_user[0] == 0 ||         /*and their is a valid user*/
         (strcmp(utmp->ut_user, user)))   /*and that user is our 'user'*/
      {
         continue;          /*skip this entry if any of that stuff failed*/
      }
      sprintf(ttydata, "/dev/%s", utmp->ut_line);

      /*ttydata is the name of the terminal to write to*/

      fd = open(ttydata, O_WRONLY | O_NDELAY);
         if ((fp = fdopen(fd, "w")) != NULL)
         {
            fputs(message, fp);
            fputs("\n", fp);
            fclose(fp);
         } else
         {
            close(fd);
         }
   }


   endutent();                       /*close the utmp file*/

   free(ttydata);

   return(0);                        /*exit with no errors*/
}

#include <stdlib.h>
#include <stdio.h>
#include "ui.h"

int main(int argc, char **argv)
{
   int retval = 0;
   int string_length = 0;
   char *message;

   string_length = input_length(argc, argv);

   message = ((char*)(malloc(string_length*(sizeof(char)))));

   retval = parser(argc, argv, message);
   error_handle(retval);

   retval = mainhello(message);
   error_handle(retval);

   free(message);

   return(retval);
}

#include <stdlib.h>
#include <stdio.h>

void error_handle(int retval)
{
   if (retval)
   {
      fprintf(stderr, "Error: exiting\n");
      exit(1);
   }
   return;
}

int spew_usage(char* argv_0)
{
   fprintf(stderr, "Usage: %s [MESSAGE]\n", argv_0);
   fprintf(stderr, "Outputs MESSAGE to all terminals owned by caller\n");
   fprintf(stderr, "With no MESSAGE \"Hello World!\" is output\n");
}

int input_length(int argc, char **argv)
{
   int counter = 1;
   int string_length = 0;

   if (argc == 1)
   {
     return(strlen("Hello World!\n"));
   }

   while (counter < argc)
   {
      string_length += (strlen(argv[counter]));
      counter++;
   }

   string_length += argc;  /*to account for spaces*/

   return(string_length);
}


int parser(int argc, char **argv, char *message)
{
   int retval = 0;
   int counter = 2;

   if (argc == 1)
   {
      strcpy(message, "Hello World!\n");
      return(retval);

   }

   if (!(strcmp(argv[1], "--help")))
   {
      spew_usage(argv[0]);
      return(retval);
   }

   strcpy(message, argv[1]);
   strcat(message, " ");

   while (counter < argc)
   {
      strcat(message, argv[counter]);
      strcat(message, " ");
      counter++;

   }

   return(retval);
}

miniwall : ui.o hw.o
        gcc -o miniwall ui.o hw.o

ui.o : ui.c
        gcc -c -w ui.c

hw.o : hw.c
        gcc -c -w hw.c

.PHONY : clean

clean :
        rm -f *.o miniwall