games/trek/schedule.c

   1 /*-
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)schedule.c       8.1 (Berkeley) 5/31/93
  30  * $FreeBSD: src/games/trek/schedule.c,v 1.4 1999/11/30 03:49:53 billf Exp $
  31  * $DragonFly: src/games/trek/schedule.c,v 1.3 2006/09/07 21:19:44 pavalos Exp $
  32  */
  33
  34 #include "trek.h"
  35
  36 /*
  37 **  SCHEDULE AN EVENT
  38 **
  39 **      An event of type 'type' is scheduled for time NOW + 'offset'
  40 **      into the first available slot.  'x', 'y', and 'z' are
  41 **      considered the attributes for this event.
  42 **
  43 **      The address of the slot is returned.
  44 */
  45
  46 struct event *
  47 schedule(int type, double offset, char x, char y, char z)
  48 {
  49         struct event    *e;
  50         int             i;
  51         double                  date;
  52
  53         date = Now.date + offset;
  54         for (i = 0; i < MAXEVENTS; i++) {
  55                 e = &Event[i];
  56                 if (e->evcode)
  57                         continue;
  58                 /* got a slot */
  59 #ifdef xTRACE
  60                 if (Trace)
  61                         printf("schedule: type %d @ %.2f slot %d parm %d %d %d\n",
  62                                 type, date, i, x, y, z);
  63 #endif
  64                 e->evcode = type;
  65                 e->date = date;
  66                 e->x = x;
  67                 e->y = y;
  68                 e->systemname = z;
  69                 Now.eventptr[type] = e;
  70                 return (e);
  71         }
  72         syserr("Cannot schedule event %d parm %d %d %d", type, x, y, z);
  73         /* NOTREACHED */
  74         return(NULL);
  75 }
  76
  77
  78 /*
  79 **  RESCHEDULE AN EVENT
  80 **
  81 **      The event pointed to by 'e' is rescheduled to the current
  82 **      time plus 'offset'.
  83 */
  84
  85 void
  86 reschedule(struct event *e1, double offset)
  87 {
  88         double                  date;
  89         struct event    *e;
  90
  91         e = e1;
  92
  93         date = Now.date + offset;
  94         e->date = date;
  95 #ifdef xTRACE
  96         if (Trace)
  97                 printf("reschedule: type %d parm %d %d %d @ %.2f\n",
  98                         e->evcode, e->x, e->y, e->systemname, date);
  99 #endif
 100         return;
 101 }
 102
 103
 104 /*
 105 **  UNSCHEDULE AN EVENT
 106 **
 107 **      The event at slot 'e' is deleted.
 108 */
 109
 110 void
 111 unschedule(struct event *e1)
 112 {
 113         struct event    *e;
 114
 115         e = e1;
 116
 117 #ifdef xTRACE
 118         if (Trace)
 119                 printf("unschedule: type %d @ %.2f parm %d %d %d\n",
 120                         e->evcode, e->date, e->x, e->y, e->systemname);
 121 #endif
 122         Now.eventptr[e->evcode & E_EVENT] = 0;
 123         e->date = TOOLARGE;
 124         e->evcode = 0;
 125         return;
 126 }
 127
 128
 129 /*
 130 **  Abreviated schedule routine
 131 **
 132 **      Parameters are the event index and a factor for the time
 133 **      figure.
 134 */
 135
 136 struct event *
 137 xsched(int ev1, int factor, int x, int y, int z)
 138 {
 139         int     ev;
 140         double when;
 141
 142         ev = ev1;
 143         when = -Param.eventdly[ev] * Param.time * log(franf()) / factor;
 144         return (schedule(ev, when, x, y, z));
 145 }
 146
 147
 148 /*
 149 **  Simplified reschedule routine
 150 **
 151 **      Parameters are the event index, the initial date, and the
 152 **      division factor.  Look at the code to see what really happens.
 153 */
 154
 155 void
 156 xresched(struct event *e1, int ev1, int factor)
 157 {
 158         int             ev;
 159         struct event    *e;
 160         double when;
 161
 162         ev = ev1;
 163         e = e1;
 164         when = -Param.eventdly[ev] * Param.time * log(franf()) / factor;
 165         reschedule(e, when);
 166 }