xref: /dragonfly/games/trek/schedule.c (revision 36a3d1d6)
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 }
167