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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 #if 0 36 static char sccsid[] = "@(#)dumpgame.c 8.1 (Berkeley) 5/31/93"; 37 #endif 38 static const char rcsid[] = 39 "$FreeBSD: src/games/trek/dumpgame.c,v 1.6 1999/11/30 03:49:46 billf Exp $"; 40 #endif /* not lint */ 41 42 #include <fcntl.h> 43 44 # include "trek.h" 45 46 /*** THIS CONSTANT MUST CHANGE AS THE DATA SPACES CHANGE ***/ 47 # define VERSION 2 48 49 struct dump 50 { 51 char *area; 52 int count; 53 }; 54 55 56 struct dump Dump_template[] = 57 { 58 (char *)&Ship, sizeof (Ship), 59 (char *)&Now, sizeof (Now), 60 (char *)&Param, sizeof (Param), 61 (char *)&Etc, sizeof (Etc), 62 (char *)&Game, sizeof (Game), 63 (char *)Sect, sizeof (Sect), 64 (char *)Quad, sizeof (Quad), 65 (char *)&Move, sizeof (Move), 66 (char *)Event, sizeof (Event), 67 0 68 }; 69 70 /* 71 ** DUMP GAME 72 ** 73 ** This routine dumps the game onto the file "trek.dump". The 74 ** first two bytes of the file are a version number, which 75 ** reflects whether this image may be used. Obviously, it must 76 ** change as the size, content, or order of the data structures 77 ** output change. 78 */ 79 80 dumpgame() 81 { 82 int version; 83 int fd; 84 struct dump *d; 85 int i; 86 87 if ((fd = creat("trek.dump", 0644)) < 0) 88 return (printf("cannot dump\n")); 89 version = VERSION; 90 write(fd, &version, sizeof version); 91 92 /* output the main data areas */ 93 for (d = Dump_template; d->area; d++) 94 { 95 write(fd, &d->area, sizeof d->area); 96 i = d->count; 97 write(fd, d->area, i); 98 } 99 100 close(fd); 101 } 102 103 104 /* 105 ** RESTORE GAME 106 ** 107 ** The game is restored from the file "trek.dump". In order for 108 ** this to succeed, the file must exist and be readable, must 109 ** have the correct version number, and must have all the appro- 110 ** priate data areas. 111 ** 112 ** Return value is zero for success, one for failure. 113 */ 114 115 restartgame() 116 { 117 int fd; 118 int version; 119 120 if ((fd = open("trek.dump", O_RDONLY)) < 0 || 121 read(fd, &version, sizeof version) != sizeof version || 122 version != VERSION || 123 readdump(fd)) 124 { 125 printf("cannot restart\n"); 126 close(fd); 127 return (1); 128 } 129 130 close(fd); 131 return (0); 132 } 133 134 135 /* 136 ** READ DUMP 137 ** 138 ** This is the business end of restartgame(). It reads in the 139 ** areas. 140 ** 141 ** Returns zero for success, one for failure. 142 */ 143 144 readdump(fd1) 145 int fd1; 146 { 147 int fd; 148 struct dump *d; 149 int i; 150 long junk; 151 152 fd = fd1; 153 154 for (d = Dump_template; d->area; d++) 155 { 156 if (read(fd, &junk, sizeof junk) != (sizeof junk)) 157 return (1); 158 if ((char *)junk != d->area) 159 return (1); 160 i = d->count; 161 if (read(fd, d->area, i) != i) 162 return (1); 163 } 164 165 /* make quite certain we are at EOF */ 166 return (read(fd, &junk, 1)); 167 } 168