lib/rfc1123.c

   1 /*
   2  * $Id: rfc1123.c,v 1.7 1997/02/18 23:53:48 wessels Exp $
   3  *
   4  * DEBUG:
   5  * AUTHOR: Harvest Derived
   6  *
   7  * SQUID Internet Object Cache  http://squid.nlanr.net/Squid/
   8  * --------------------------------------------------------
   9  *
  10  *  Squid is the result of efforts by numerous individuals from the
  11  *  Internet community.  Development is led by Duane Wessels of the
  12  *  National Laboratory for Applied Network Research and funded by
  13  *  the National Science Foundation.
  14  *
  15  *  This program is free software; you can redistribute it and/or modify
  16  *  it under the terms of the GNU General Public License as published by
  17  *  the Free Software Foundation; either version 2 of the License, or
  18  *  (at your option) any later version.
  19  *
  20  *  This program is distributed in the hope that it will be useful,
  21  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  *  GNU General Public License for more details.
  24  *
  25  *  You should have received a copy of the GNU General Public License
  26  *  along with this program; if not, write to the Free Software
  27  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  28  *
  29  */
  30
  31 /*
  32  * Copyright (c) 1994, 1995.  All rights reserved.
  33  *
  34  *   The Harvest software was developed by the Internet Research Task
  35  *   Force Research Group on Resource Discovery (IRTF-RD):
  36  *
  37  *         Mic Bowman of Transarc Corporation.
  38  *         Peter Danzig of the University of Southern California.
  39  *         Darren R. Hardy of the University of Colorado at Boulder.
  40  *         Udi Manber of the University of Arizona.
  41  *         Michael F. Schwartz of the University of Colorado at Boulder.
  42  *         Duane Wessels of the University of Colorado at Boulder.
  43  *
  44  *   This copyright notice applies to software in the Harvest
  45  *   ``src/'' directory only.  Users should consult the individual
  46  *   copyright notices in the ``components/'' subdirectories for
  47  *   copyright information about other software bundled with the
  48  *   Harvest source code distribution.
  49  *
  50  * TERMS OF USE
  51  *
  52  *   The Harvest software may be used and re-distributed without
  53  *   charge, provided that the software origin and research team are
  54  *   cited in any use of the system.  Most commonly this is
  55  *   accomplished by including a link to the Harvest Home Page
  56  *   (http://harvest.cs.colorado.edu/) from the query page of any
  57  *   Broker you deploy, as well as in the query result pages.  These
  58  *   links are generated automatically by the standard Broker
  59  *   software distribution.
  60  *
  61  *   The Harvest software is provided ``as is'', without express or
  62  *   implied warranty, and with no support nor obligation to assist
  63  *   in its use, correction, modification or enhancement.  We assume
  64  *   no liability with respect to the infringement of copyrights,
  65  *   trade secrets, or any patents, and are not responsible for
  66  *   consequential damages.  Proper use of the Harvest software is
  67  *   entirely the responsibility of the user.
  68  *
  69  * DERIVATIVE WORKS
  70  *
  71  *   Users may make derivative works from the Harvest software, subject
  72  *   to the following constraints:
  73  *
  74  *     - You must include the above copyright notice and these
  75  *       accompanying paragraphs in all forms of derivative works,
  76  *       and any documentation and other materials related to such
  77  *       distribution and use acknowledge that the software was
  78  *       developed at the above institutions.
  79  *
  80  *     - You must notify IRTF-RD regarding your distribution of
  81  *       the derivative work.
  82  *
  83  *     - You must clearly notify users that your are distributing
  84  *       a modified version and not the original Harvest software.
  85  *
  86  *     - Any derivative product is also subject to these copyright
  87  *       and use restrictions.
  88  *
  89  *   Note that the Harvest software is NOT in the public domain.  We
  90  *   retain copyright, as specified above.
  91  *
  92  * HISTORY OF FREE SOFTWARE STATUS
  93  *
  94  *   Originally we required sites to license the software in cases
  95  *   where they were going to build commercial products/services
  96  *   around Harvest.  In June 1995 we changed this policy.  We now
  97  *   allow people to use the core Harvest software (the code found in
  98  *   the Harvest ``src/'' directory) for free.  We made this change
  99  *   in the interest of encouraging the widest possible deployment of
 100  *   the technology.  The Harvest software is really a reference
 101  *   implementation of a set of protocols and formats, some of which
 102  *   we intend to standardize.  We encourage commercial
 103  *   re-implementations of code complying to this set of standards.
 104  */
 105
 106 #include "config.h"
 107
 108
 109 /*
 110  *  Adapted from HTSUtils.c in CERN httpd 3.0 (http://info.cern.ch/httpd/)
 111  *  by Darren Hardy <hardy@cs.colorado.edu>, November 1994.
 112  */
 113 #if HAVE_STDIO_H
 114 #include <stdio.h>
 115 #endif
 116 #if HAVE_STRING_H
 117 #include <string.h>
 118 #endif
 119 #if HAVE_CTYPE_H
 120 #include <ctype.h>
 121 #endif
 122 #if HAVE_SYS_TYPES_H
 123 #include <sys/types.h>
 124 #endif
 125 #if HAVE_TIME_H
 126 #include <time.h>
 127 #endif
 128 #if HAVE_SYS_TIME_H
 129 #include <sys/time.h>
 130 #endif
 131
 132 #include "ansiproto.h"
 133 #include "util.h"
 134
 135 #define RFC850_STRFTIME "%A, %d-%b-%y %H:%M:%S GMT"
 136 #define RFC1123_STRFTIME "%a, %d %b %Y %H:%M:%S GMT"
 137
 138 static int make_month _PARAMS((const char *s));
 139 static int make_num _PARAMS((const char *s));
 140
 141 static char *month_names[12] =
 142 {
 143     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
 144     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 145 };
 146
 147
 148 static int
 149 make_num(const char *s)
 150 {
 151     if (*s >= '0' && *s <= '9')
 152         return 10 * (*s - '0') + *(s + 1) - '0';
 153     else
 154         return *(s + 1) - '0';
 155 }
 156
 157 static int
 158 make_month(const char *s)
 159 {
 160     int i;
 161     char month[3];
 162
 163     month[0] = toupper(*s);
 164     month[1] = tolower(*(s + 1));
 165     month[2] = tolower(*(s + 2));
 166
 167     for (i = 0; i < 12; i++)
 168         if (!strncmp(month_names[i], month, 3))
 169             return i;
 170     return 0;
 171 }
 172
 173
 174 time_t
 175 parse_rfc1123(const char *str)
 176 {
 177     const char *s;
 178     struct tm tm;
 179     time_t t;
 180
 181     if (!str)
 182         return -1;
 183
 184     memset(&tm, '\0', sizeof(struct tm));
 185     if ((s = strchr(str, ','))) {       /* Thursday, 10-Jun-93 01:29:59 GMT */
 186         s++;                    /* or: Thu, 10 Jan 1993 01:29:59 GMT */
 187         while (*s && *s == ' ')
 188             s++;
 189         if (strchr(s, '-')) {   /* First format */
 190             if ((int) strlen(s) < 18)
 191                 return -1;
 192             tm.tm_mday = make_num(s);
 193             tm.tm_mon = make_month(s + 3);
 194             tm.tm_year = make_num(s + 7);
 195             tm.tm_hour = make_num(s + 10);
 196             tm.tm_min = make_num(s + 13);
 197             tm.tm_sec = make_num(s + 16);
 198         } else {                /* Second format */
 199             if ((int) strlen(s) < 20)
 200                 return -1;
 201             tm.tm_mday = make_num(s);
 202             tm.tm_mon = make_month(s + 3);
 203             tm.tm_year = (100 * make_num(s + 7) - 1900) + make_num(s + 9);
 204             tm.tm_hour = make_num(s + 12);
 205             tm.tm_min = make_num(s + 15);
 206             tm.tm_sec = make_num(s + 18);
 207
 208         }
 209     } else {                    /* Try the other format:        */
 210         s = str;                /* Wed Jun  9 01:29:59 1993 GMT */
 211         while (*s && *s == ' ')
 212             s++;
 213         if ((int) strlen(s) < 24)
 214             return -1;
 215         tm.tm_mday = make_num(s + 8);
 216         tm.tm_mon = make_month(s + 4);
 217         tm.tm_year = make_num(s + 22);
 218         tm.tm_hour = make_num(s + 11);
 219         tm.tm_min = make_num(s + 14);
 220         tm.tm_sec = make_num(s + 17);
 221     }
 222     if (tm.tm_sec < 0 || tm.tm_sec > 59 ||
 223         tm.tm_min < 0 || tm.tm_min > 59 ||
 224         tm.tm_hour < 0 || tm.tm_hour > 23 ||
 225         tm.tm_mday < 1 || tm.tm_mday > 31 ||
 226         tm.tm_mon < 0 || tm.tm_mon > 11 ||
 227         tm.tm_year < 70 || tm.tm_year > 120) {
 228         return -1;
 229     }
 230     tm.tm_isdst = -1;
 231
 232 #ifdef HAVE_TIMEGM
 233     t = timegm(&tm);
 234 #elif HAVE_TM_GMTOFF
 235     t = mktime(&tm);
 236     {
 237         time_t cur_t = time(NULL);
 238         struct tm *local = localtime(&cur_t);
 239         t += local->tm_gmtoff;
 240     }
 241 #else
 242     /* some systems do not have tm_gmtoff so we fake it */
 243     t = mktime(&tm);
 244     {
 245         time_t dst = 0;
 246 #ifndef _TIMEZONE
 247         extern time_t timezone;
 248 #endif /* _TIMEZONE */
 249         /*
 250          * The following assumes a fixed DST offset of 1 hour,
 251          * which is probably wrong.
 252          */
 253         if (tm.tm_isdst > 0)
 254             dst = -3600;
 255         t -= (timezone + dst);
 256     }
 257 #endif
 258     return t;
 259 }
 260
 261 const char *
 262 mkrfc1123(time_t t)
 263 {
 264     static char buf[128];
 265
 266     struct tm *gmt = gmtime(&t);
 267
 268     buf[0] = '\0';
 269     strftime(buf, 127, RFC1123_STRFTIME, gmt);
 270     return buf;
 271 }
 272
 273 const char *
 274 mkhttpdlogtime(const time_t * t)
 275 {
 276     static char buf[128];
 277
 278     struct tm *gmt = gmtime(t);
 279
 280 #ifndef USE_GMT
 281     int gmt_min, gmt_hour, gmt_yday, day_offset;
 282     size_t len;
 283     struct tm *lt;
 284     int min_offset;
 285
 286     /* localtime & gmtime may use the same static data */
 287     gmt_min = gmt->tm_min;
 288     gmt_hour = gmt->tm_hour;
 289     gmt_yday = gmt->tm_yday;
 290
 291     lt = localtime(t);
 292     day_offset = lt->tm_yday - gmt_yday;
 293     min_offset = day_offset * 1440 + (lt->tm_hour - gmt_hour) * 60
 294         + (lt->tm_min - gmt_min);
 295
 296     /* wrap round on end of year */
 297     if (day_offset > 1)
 298         day_offset = -1;
 299     else if (day_offset < -1)
 300         day_offset = 1;
 301
 302     len = strftime(buf, 127 - 5, "%d/%b/%Y:%H:%M:%S ", lt);
 303     sprintf(buf + len, "%+03d%02d",
 304         (min_offset / 60) % 24,
 305         min_offset % 60);
 306 #else /* USE_GMT */
 307     buf[0] = '\0';
 308     strftime(buf, 127, "%d/%b/%Y:%H:%M:%S -000", gmt);
 309 #endif /* USE_GMT */
 310
 311     return buf;
 312 }
 313
 314 #if 0
 315 int
 316 main()
 317 {
 318     char *x;
 319     time_t t, pt;
 320
 321     t = time(NULL);
 322     x = mkrfc1123(t);
 323     printf("HTTP Time: %s\n", x);
 324
 325     pt = parse_rfc1123(x);
 326     printf("Parsed: %d vs. %d\n", pt, t);
 327 }
 328
 329 #endif