BSD 4_2 release

[unix-history] / usr / src / games / trek / schedule.c

#ifndef lint
static char sccsid[] = "@(#)schedule.c  4.2     (Berkeley)      5/27/83";
#endif not lint

# include       "trek.h"

/*
**  SCHEDULE AN EVENT
**
**      An event of type 'type' is scheduled for time NOW + 'offset'
**      into the first available slot.  'x', 'y', and 'z' are
**      considered the attributes for this event.
**
**      The address of the slot is returned.
*/

struct event *schedule(type, offset, x, y, z)
int     type;
double  offset;
char    x, y;
char    z;
{
       register struct event   *e;
       register int            i;
       double                  date;

       date = Now.date + offset;
       for (i = 0; i < MAXEVENTS; i++)
       {
               e = &Event[i];
               if (e->evcode)
                       continue;
               /* got a slot */
#               ifdef xTRACE
               if (Trace)
                       printf("schedule: type %d @ %.2f slot %d parm %d %d %d\n",
                               type, date, i, x, y, z);
#               endif
               e->evcode = type;
               e->date = date;
               e->x = x;
               e->y = y;
               e->systemname = z;
               Now.eventptr[type] = e;
               return (e);
       }
       syserr("Cannot schedule event %d parm %d %d %d", type, x, y, z);
}


/*
**  RESCHEDULE AN EVENT
**
**      The event pointed to by 'e' is rescheduled to the current
**      time plus 'offset'.
*/

reschedule(e1, offset)
struct event    *e1;
double          offset;
{
       double                  date;
       register struct event   *e;

       e = e1;

       date = Now.date + offset;
       e->date = date;
#       ifdef xTRACE
       if (Trace)
               printf("reschedule: type %d parm %d %d %d @ %.2f\n",
                       e->evcode, e->x, e->y, e->systemname, date);
#       endif
       return;
}


/*
**  UNSCHEDULE AN EVENT
**
**      The event at slot 'e' is deleted.
*/

unschedule(e1)
struct event    *e1;
{
       register struct event   *e;

       e = e1;

#       ifdef xTRACE
       if (Trace)
               printf("unschedule: type %d @ %.2f parm %d %d %d\n",
                       e->evcode, e->date, e->x, e->y, e->systemname);
#       endif
       Now.eventptr[e->evcode & E_EVENT] = 0;
       e->date = 1e50;
       e->evcode = 0;
       return;
}


/*
**  Abreviated schedule routine
**
**      Parameters are the event index and a factor for the time
**      figure.
*/

struct event *xsched(ev1, factor, x, y, z)
int     ev1;
int     factor;
int     x, y, z;
{
       register int    ev;

       ev = ev1;
       return (schedule(ev, -Param.eventdly[ev] * Param.time * log(franf()) / factor, x, y, z));
}


/*
**  Simplified reschedule routine
**
**      Parameters are the event index, the initial date, and the
**      division factor.  Look at the code to see what really happens.
*/

xresched(e1, ev1, factor)
struct event    *e1;
int             ev1;
int             factor;
{
       register int            ev;
       register struct event   *e;

       ev = ev1;
       e = e1;
       reschedule(e, -Param.eventdly[ev] * Param.time * log(franf()) / factor);
}