date.c revision 1.44
1/* $NetBSD: date.c,v 1.44 2006/08/17 10:03:53 jnemeth Exp $ */ 2 3/* 4 * Copyright (c) 1985, 1987, 1988, 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__COPYRIGHT( 35"@(#) Copyright (c) 1985, 1987, 1988, 1993\n\ 36 The Regents of the University of California. All rights reserved.\n"); 37#endif /* not lint */ 38 39#ifndef lint 40#if 0 41static char sccsid[] = "@(#)date.c 8.2 (Berkeley) 4/28/95"; 42#else 43__RCSID("$NetBSD: date.c,v 1.44 2006/08/17 10:03:53 jnemeth Exp $"); 44#endif 45#endif /* not lint */ 46 47#include <sys/param.h> 48#include <sys/time.h> 49 50#include <ctype.h> 51#include <err.h> 52#include <fcntl.h> 53#include <locale.h> 54#include <stdio.h> 55#include <stdlib.h> 56#include <string.h> 57#include <syslog.h> 58#include <time.h> 59#include <tzfile.h> 60#include <unistd.h> 61#include <util.h> 62 63#include "extern.h" 64 65static time_t tval; 66static int aflag, rflag, nflag; 67int retval; 68 69static void badformat(void); 70static void badtime(void); 71static void setthetime(const char *); 72static void usage(void); 73 74int 75main(int argc, char *argv[]) 76{ 77 char *buf; 78 size_t bufsiz; 79 const char *format; 80 int ch; 81 82 setprogname(argv[0]); 83 (void)setlocale(LC_ALL, ""); 84 85 while ((ch = getopt(argc, argv, "anr:u")) != -1) { 86 switch (ch) { 87 case 'a': /* adjust time slowly */ 88 aflag = 1; 89 nflag = 1; 90 break; 91 case 'n': /* don't set network */ 92 nflag = 1; 93 break; 94 case 'r': /* user specified seconds */ 95 rflag = 1; 96 tval = strtol(optarg, NULL, 0); 97 break; 98 case 'u': /* do everything in UTC */ 99 (void)putenv("TZ=UTC0"); 100 break; 101 default: 102 usage(); 103 } 104 } 105 argc -= optind; 106 argv += optind; 107 108 if (!rflag && time(&tval) == -1) 109 err(EXIT_FAILURE, "time"); 110 111 format = "%a %b %e %H:%M:%S %Z %Y"; 112 113 /* allow the operands in any order */ 114 if (*argv && **argv == '+') { 115 format = *argv + 1; 116 ++argv; 117 } 118 119 if (*argv) { 120 setthetime(*argv); 121 ++argv; 122 } 123 124 if (*argv && **argv == '+') 125 format = *argv + 1; 126 127 if ((buf = malloc(bufsiz = 1024)) == NULL) 128 goto bad; 129 while (strftime(buf, bufsiz, format, localtime(&tval)) == 0) 130 if ((buf = realloc(buf, bufsiz <<= 1)) == NULL) 131 goto bad; 132 (void)printf("%s\n", buf); 133 free(buf); 134 return 0; 135bad: 136 err(1, "Cannot allocate format buffer"); 137} 138 139static void 140badformat(void) 141{ 142 warnx("illegal time format"); 143 usage(); 144} 145 146static void 147badtime(void) 148{ 149 errx(EXIT_FAILURE, "illegal time"); 150 /* NOTREACHED */ 151} 152 153#define ATOI2(s) ((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0')) 154 155static void 156setthetime(const char *p) 157{ 158 struct timeval tv; 159 time_t new_time; 160 struct tm *lt; 161 const char *dot, *t; 162 int len, yearset; 163 164 for (t = p, dot = NULL; *t; ++t) { 165 if (isdigit((unsigned char)*t)) 166 continue; 167 if (*t == '.' && dot == NULL) { 168 dot = t; 169 continue; 170 } 171 badformat(); 172 } 173 174 lt = localtime(&tval); 175 176 lt->tm_isdst = -1; /* Divine correct DST */ 177 178 if (dot != NULL) { /* .ss */ 179 len = strlen(dot); 180 if (len != 3) 181 badformat(); 182 ++dot; 183 lt->tm_sec = ATOI2(dot); 184 } else { 185 len = 0; 186 lt->tm_sec = 0; 187 } 188 189 yearset = 0; 190 switch (strlen(p) - len) { 191 case 12: /* cc */ 192 lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE; 193 yearset = 1; 194 /* FALLTHROUGH */ 195 case 10: /* yy */ 196 if (yearset) { 197 lt->tm_year += ATOI2(p); 198 } else { 199 yearset = ATOI2(p); 200 if (yearset < 69) 201 lt->tm_year = yearset + 2000 - TM_YEAR_BASE; 202 else 203 lt->tm_year = yearset + 1900 - TM_YEAR_BASE; 204 } 205 /* FALLTHROUGH */ 206 case 8: /* mm */ 207 lt->tm_mon = ATOI2(p); 208 --lt->tm_mon; /* time struct is 0 - 11 */ 209 /* FALLTHROUGH */ 210 case 6: /* dd */ 211 lt->tm_mday = ATOI2(p); 212 /* FALLTHROUGH */ 213 case 4: /* hh */ 214 lt->tm_hour = ATOI2(p); 215 /* FALLTHROUGH */ 216 case 2: /* mm */ 217 lt->tm_min = ATOI2(p); 218 break; 219 case 0: /* was just .sss */ 220 if (len != 0) 221 break; 222 /* FALLTHROUGH */ 223 default: 224 badformat(); 225 } 226 227 /* convert broken-down time to UTC clock time */ 228 if ((new_time = mktime(lt)) == -1) 229 badtime(); 230 231 /* set the time */ 232 if (nflag || netsettime(new_time)) { 233 logwtmp("|", "date", ""); 234 if (aflag) { 235 tv.tv_sec = new_time - tval; 236 tv.tv_usec = 0; 237 if (adjtime(&tv, NULL)) 238 err(EXIT_FAILURE, "adjtime"); 239 } else { 240 tval = new_time; 241 tv.tv_sec = tval; 242 tv.tv_usec = 0; 243 if (settimeofday(&tv, NULL)) 244 err(EXIT_FAILURE, "settimeofday"); 245 } 246 logwtmp("{", "date", ""); 247 } 248 249 if ((p = getlogin()) == NULL) 250 p = "???"; 251 syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p); 252} 253 254static void 255usage(void) 256{ 257 (void)fprintf(stderr, 258 "usage: %s [-u] [-r seconds] [+format]\n", getprogname()); 259 (void)fprintf(stderr, " %s [-anu] [[[[[cc]yy]mm]dd]hh]mm[.ss]\n", 260 getprogname()); 261 exit(EXIT_FAILURE); 262 /* NOTREACHED */ 263} 264