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 * @(#)dumpgame.c 8.1 (Berkeley) 5/31/93 34 * $FreeBSD: src/games/trek/dumpgame.c,v 1.6 1999/11/30 03:49:46 billf Exp $ 35 * $DragonFly: src/games/trek/dumpgame.c,v 1.2 2003/06/17 04:25:25 dillon Exp $ 36 */ 37 38 #include <fcntl.h> 39 40 # include "trek.h" 41 42 /*** THIS CONSTANT MUST CHANGE AS THE DATA SPACES CHANGE ***/ 43 # define VERSION 2 44 45 struct dump 46 { 47 char *area; 48 int count; 49 }; 50 51 52 struct dump Dump_template[] = 53 { 54 (char *)&Ship, sizeof (Ship), 55 (char *)&Now, sizeof (Now), 56 (char *)&Param, sizeof (Param), 57 (char *)&Etc, sizeof (Etc), 58 (char *)&Game, sizeof (Game), 59 (char *)Sect, sizeof (Sect), 60 (char *)Quad, sizeof (Quad), 61 (char *)&Move, sizeof (Move), 62 (char *)Event, sizeof (Event), 63 0 64 }; 65 66 /* 67 ** DUMP GAME 68 ** 69 ** This routine dumps the game onto the file "trek.dump". The 70 ** first two bytes of the file are a version number, which 71 ** reflects whether this image may be used. Obviously, it must 72 ** change as the size, content, or order of the data structures 73 ** output change. 74 */ 75 76 dumpgame() 77 { 78 int version; 79 int fd; 80 struct dump *d; 81 int i; 82 83 if ((fd = creat("trek.dump", 0644)) < 0) 84 return (printf("cannot dump\n")); 85 version = VERSION; 86 write(fd, &version, sizeof version); 87 88 /* output the main data areas */ 89 for (d = Dump_template; d->area; d++) 90 { 91 write(fd, &d->area, sizeof d->area); 92 i = d->count; 93 write(fd, d->area, i); 94 } 95 96 close(fd); 97 } 98 99 100 /* 101 ** RESTORE GAME 102 ** 103 ** The game is restored from the file "trek.dump". In order for 104 ** this to succeed, the file must exist and be readable, must 105 ** have the correct version number, and must have all the appro- 106 ** priate data areas. 107 ** 108 ** Return value is zero for success, one for failure. 109 */ 110 111 restartgame() 112 { 113 int fd; 114 int version; 115 116 if ((fd = open("trek.dump", O_RDONLY)) < 0 || 117 read(fd, &version, sizeof version) != sizeof version || 118 version != VERSION || 119 readdump(fd)) 120 { 121 printf("cannot restart\n"); 122 close(fd); 123 return (1); 124 } 125 126 close(fd); 127 return (0); 128 } 129 130 131 /* 132 ** READ DUMP 133 ** 134 ** This is the business end of restartgame(). It reads in the 135 ** areas. 136 ** 137 ** Returns zero for success, one for failure. 138 */ 139 140 readdump(fd1) 141 int fd1; 142 { 143 int fd; 144 struct dump *d; 145 int i; 146 long junk; 147 148 fd = fd1; 149 150 for (d = Dump_template; d->area; d++) 151 { 152 if (read(fd, &junk, sizeof junk) != (sizeof junk)) 153 return (1); 154 if ((char *)junk != d->area) 155 return (1); 156 i = d->count; 157 if (read(fd, d->area, i) != i) 158 return (1); 159 } 160 161 /* make quite certain we are at EOF */ 162 return (read(fd, &junk, 1)); 163 } 164