1 /* $NetBSD: dumpgame.c,v 1.15 2009/08/12 08:54:54 dholland 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)dumpgame.c 8.1 (Berkeley) 5/31/93"; 36 #else 37 __RCSID("$NetBSD: dumpgame.c,v 1.15 2009/08/12 08:54:54 dholland Exp $"); 38 #endif 39 #endif /* not lint */ 40 41 #include <stdio.h> 42 #include <err.h> 43 #include <unistd.h> 44 #include <fcntl.h> 45 #include "trek.h" 46 47 /*** THIS CONSTANT MUST CHANGE AS THE DATA SPACES CHANGE ***/ 48 #define VERSION 2 49 50 struct dump { 51 char *area; 52 int count; 53 }; 54 55 static int readdump(int); 56 57 58 static struct dump Dump_template[] = { 59 { (char *)&Ship, sizeof (Ship) }, 60 { (char *)&Now, sizeof (Now) }, 61 { (char *)&Param, sizeof (Param) }, 62 { (char *)&Etc, sizeof (Etc) }, 63 { (char *)&Game, sizeof (Game) }, 64 { (char *)Sect, sizeof (Sect) }, 65 { (char *)Quad, sizeof (Quad) }, 66 { (char *)&Move, sizeof (Move) }, 67 { (char *)Event, sizeof (Event) }, 68 { NULL, 0 } 69 }; 70 71 /* 72 ** DUMP GAME 73 ** 74 ** This routine dumps the game onto the file "trek.dump". The 75 ** first two bytes of the file are a version number, which 76 ** reflects whether this image may be used. Obviously, it must 77 ** change as the size, content, or order of the data structures 78 ** output change. 79 */ 80 81 /*ARGSUSED*/ 82 void 83 dumpgame(int v __unused) 84 { 85 int version; 86 int fd; 87 struct dump *d; 88 int i; 89 90 if ((fd = creat("trek.dump", 0644)) < 0) { 91 warn("cannot open `trek.dump'"); 92 return; 93 } 94 version = VERSION; 95 write(fd, &version, sizeof version); 96 97 /* output the main data areas */ 98 for (d = Dump_template; d->area; d++) { 99 write(fd, &d->area, sizeof d->area); 100 i = d->count; 101 write(fd, d->area, i); 102 } 103 104 close(fd); 105 } 106 107 108 /* 109 ** RESTORE GAME 110 ** 111 ** The game is restored from the file "trek.dump". In order for 112 ** this to succeed, the file must exist and be readable, must 113 ** have the correct version number, and must have all the appro- 114 ** priate data areas. 115 ** 116 ** Return value is zero for success, one for failure. 117 */ 118 119 int 120 restartgame(void) 121 { 122 int fd; 123 int version; 124 125 if ((fd = open("trek.dump", O_RDONLY)) < 0 || 126 read(fd, &version, sizeof version) != sizeof version || 127 version != VERSION || 128 readdump(fd)) { 129 printf("cannot restart\n"); 130 if (fd >= 0) 131 close(fd); 132 return (1); 133 } 134 135 close(fd); 136 return (0); 137 } 138 139 140 /* 141 ** READ DUMP 142 ** 143 ** This is the business end of restartgame(). It reads in the 144 ** areas. 145 ** 146 ** Returns zero for success, one for failure. 147 */ 148 149 static int 150 readdump(int fd1) 151 { 152 int fd; 153 struct dump *d; 154 int i; 155 long junk; 156 157 fd = fd1; 158 159 for (d = Dump_template; d->area; d++) { 160 if (read(fd, &junk, sizeof junk) != (sizeof junk)) 161 return (1); 162 if ((char *)junk != d->area) 163 return (1); 164 i = d->count; 165 if (read(fd, d->area, i) != i) 166 return (1); 167 } 168 169 /* make quite certain we are at EOF */ 170 return (read(fd, &junk, 1)); 171 } 172