#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <termios.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>

#define TRUE -1
#define FALSE 0
#define FTNLEN short
/* ftnlen defined in f2c.h */


struct termios saved_attributes;


/*
**- SUBROUTINE CLOSE_INKEY()
**- disable direct keyboard input 
*/
void close_inkey_ ()
{
  tcsetattr (STDIN_FILENO, TCSANOW, &saved_attributes);
}

/*
**- SUBROUTINE OPEN_INKEY()
**- enable direct keyboard input 
*/
void open_inkey_ ()
{
  struct termios tattr;
  if (!isatty (STDIN_FILENO))
  {
    fprintf (stderr, "Not a terminal. \n");
    exit (EXIT_FAILURE);
  }
  tcgetattr (STDIN_FILENO, &saved_attributes);
  atexit (close_inkey_); 
  tcgetattr (STDIN_FILENO, &tattr);
  tattr.c_iflag &= ~(ISTRIP);
  tattr.c_lflag &= ~(ICANON|ECHO);
  tattr.c_cc[VMIN] = 0;
  tattr.c_cc[VTIME] = 0;
  tcsetattr (STDIN_FILENO, TCSAFLUSH, &tattr);
}

/*
**- SUBROUTINE WAIT_INPUT(INUNIT,WASKEY,TESTKEY)
**- waits for the input on the INUNIT or standard input (if TESTKEY=.TRUE.)
**- to become available. WASKEY is true if key was pressed.
**- input parameters:   inunit<i> : c unit number
**-                     testkey<l> : wait for standard input too ?
**- output parameters : waskey<l> : was key pressed ?
*/
void wait_input_ (inunit, waskey, testkey)
int *inunit, *waskey, *testkey;
{
  fd_set read_fd_set;

  *waskey = FALSE;
  FD_ZERO (&read_fd_set);
  FD_SET (*inunit, &read_fd_set);
  if (*testkey)
    FD_SET (STDIN_FILENO, &read_fd_set);
  if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, NULL) <0)
  {
    perror ("select");
    exit (EXIT_FAILURE);
  } 
  if (*testkey)
    if (FD_ISSET (STDIN_FILENO, &read_fd_set))
      *waskey = TRUE;
}

/*
**- SUBROUTINE KEY_READY(WASKEY)
**- checks is standar input is available
**- output parameters : waskey<l> : was key pressed ?
*/
void key_ready_ (waskey)
int *waskey;
{
  fd_set read_fd_set;
  struct timeval timeout;

  *waskey = FALSE;
  timeout.tv_sec  = 0;
  timeout.tv_usec = 0;
  FD_ZERO (&read_fd_set);
  FD_SET (STDIN_FILENO, &read_fd_set);
  if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, &timeout) <0)
  {
    perror ("select");
    exit (EXIT_FAILURE);
  } 
  if (FD_ISSET (STDIN_FILENO, &read_fd_set))
    *waskey = TRUE;
}

/*
**- SUBROUTINE WAIT_KEY()
**- waits for standar input to become available
*/
void wait_key_ ()
{
  fd_set read_fd_set;

  FD_ZERO (&read_fd_set);
  FD_SET (STDIN_FILENO, &read_fd_set);
  if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, NULL) <0)
  {
    perror ("select");
    exit (EXIT_FAILURE);
  } 
}

/*
**- INTEGER FUNCTION MY_GETC(CH_READ)
**- get next character from standar input. function returns
**- -1 , CH_READ=CHAR(0) if input empty
**-  0 , CH_READ if input not empty
**- output parameters : ch_read<c1> : input character
*/
int my_getc_ (ch_read, ch_len)
char *ch_read;
FTNLEN ch_len;
{
  int status;
  status = read(STDIN_FILENO,ch_read,1);
  if (status != 1)
  {
    *ch_read = 0;
    return -1;
  }
   else
  {
    return 0;
  }
}