1 /* $NetBSD: dumpgame.c,v 1.7 1999/09/08 21:45:32 jsm Exp $ */ 2 3 /* 4 * Copyright (c) 1980, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)dumpgame.c 8.1 (Berkeley) 5/31/93"; 40 #else 41 __RCSID("$NetBSD: dumpgame.c,v 1.7 1999/09/08 21:45:32 jsm Exp $"); 42 #endif 43 #endif /* not lint */ 44 45 #include <stdio.h> 46 #include <err.h> 47 #include <unistd.h> 48 #include <fcntl.h> 49 #include "trek.h" 50 51 /*** THIS CONSTANT MUST CHANGE AS THE DATA SPACES CHANGE ***/ 52 # define VERSION 2 53 54 struct dump 55 { 56 char *area; 57 int count; 58 }; 59 60 static int readdump __P((int)); 61 62 63 struct dump Dump_template[] = 64 { 65 { (char *)&Ship, sizeof (Ship) }, 66 { (char *)&Now, sizeof (Now) }, 67 { (char *)&Param, sizeof (Param) }, 68 { (char *)&Etc, sizeof (Etc) }, 69 { (char *)&Game, sizeof (Game) }, 70 { (char *)Sect, sizeof (Sect) }, 71 { (char *)Quad, sizeof (Quad) }, 72 { (char *)&Move, sizeof (Move) }, 73 { (char *)Event, sizeof (Event) }, 74 { NULL, 0 } 75 }; 76 77 /* 78 ** DUMP GAME 79 ** 80 ** This routine dumps the game onto the file "trek.dump". The 81 ** first two bytes of the file are a version number, which 82 ** reflects whether this image may be used. Obviously, it must 83 ** change as the size, content, or order of the data structures 84 ** output change. 85 */ 86 87 /*ARGSUSED*/ 88 void 89 dumpgame(v) 90 int v __attribute__((__unused__)); 91 { 92 int version; 93 int fd; 94 struct dump *d; 95 int i; 96 97 if ((fd = creat("trek.dump", 0644)) < 0) { 98 warn("cannot open `trek.dump'"); 99 return; 100 } 101 version = VERSION; 102 write(fd, &version, sizeof version); 103 104 /* output the main data areas */ 105 for (d = Dump_template; d->area; d++) 106 { 107 write(fd, &d->area, sizeof d->area); 108 i = d->count; 109 write(fd, d->area, i); 110 } 111 112 close(fd); 113 } 114 115 116 /* 117 ** RESTORE GAME 118 ** 119 ** The game is restored from the file "trek.dump". In order for 120 ** this to succeed, the file must exist and be readable, must 121 ** have the correct version number, and must have all the appro- 122 ** priate data areas. 123 ** 124 ** Return value is zero for success, one for failure. 125 */ 126 127 int 128 restartgame() 129 { 130 int fd; 131 int version; 132 133 if ((fd = open("trek.dump", O_RDONLY)) < 0 || 134 read(fd, &version, sizeof version) != sizeof version || 135 version != VERSION || 136 readdump(fd)) 137 { 138 printf("cannot restart\n"); 139 close(fd); 140 return (1); 141 } 142 143 close(fd); 144 return (0); 145 } 146 147 148 /* 149 ** READ DUMP 150 ** 151 ** This is the business end of restartgame(). It reads in the 152 ** areas. 153 ** 154 ** Returns zero for success, one for failure. 155 */ 156 157 static int 158 readdump(fd1) 159 int fd1; 160 { 161 int fd; 162 struct dump *d; 163 int i; 164 long junk; 165 166 fd = fd1; 167 168 for (d = Dump_template; d->area; d++) 169 { 170 if (read(fd, &junk, sizeof junk) != (sizeof junk)) 171 return (1); 172 if ((char *)junk != d->area) 173 return (1); 174 i = d->count; 175 if (read(fd, d->area, i) != i) 176 return (1); 177 } 178 179 /* make quite certain we are at EOF */ 180 return (read(fd, &junk, 1)); 181 } 182