lib/rfc1123.c

   1
   2 /*
   3  * $Id: rfc1123.c,v 1.24 2000/03/27 21:56:21 wessels Exp $
   4  *
   5  * DEBUG:
   6  * AUTHOR: Harvest Derived
   7  *
   8  * SQUID Internet Object Cache  http://squid.nlanr.net/Squid/
   9  * ----------------------------------------------------------
  10  *
  11  *  Squid is the result of efforts by numerous individuals from the
  12  *  Internet community.  Development is led by Duane Wessels of the
  13  *  National Laboratory for Applied Network Research and funded by the
  14  *  National Science Foundation.  Squid is Copyrighted (C) 1998 by
  15  *  the Regents of the University of California.  Please see the
  16  *  COPYRIGHT file for full details.  Squid incorporates software
  17  *  developed and/or copyrighted by other sources.  Please see the
  18  *  CREDITS file for full details.
  19  *
  20  *  This program is free software; you can redistribute it and/or modify
  21  *  it under the terms of the GNU General Public License as published by
  22  *  the Free Software Foundation; either version 2 of the License, or
  23  *  (at your option) any later version.
  24  *
  25  *  This program is distributed in the hope that it will be useful,
  26  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  27  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28  *  GNU General Public License for more details.
  29  *
  30  *  You should have received a copy of the GNU General Public License
  31  *  along with this program; if not, write to the Free Software
  32  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  33  *
  34  */
  35
  36 #include "config.h"
  37
  38
  39 /*
  40  *  Adapted from HTSUtils.c in CERN httpd 3.0 (http://info.cern.ch/httpd/)
  41  *  by Darren Hardy <hardy@cs.colorado.edu>, November 1994.
  42  */
  43 #if HAVE_STDIO_H
  44 #include <stdio.h>
  45 #endif
  46 #if HAVE_STDLIB_H
  47 #include <stdlib.h>
  48 #endif
  49 #if HAVE_STRING_H
  50 #include <string.h>
  51 #endif
  52 #if HAVE_CTYPE_H
  53 #include <ctype.h>
  54 #endif
  55 #if HAVE_SYS_TYPES_H
  56 #include <sys/types.h>
  57 #endif
  58 #if HAVE_TIME_H
  59 #include <time.h>
  60 #endif
  61 #if HAVE_SYS_TIME_H
  62 #include <sys/time.h>
  63 #endif
  64
  65 #include "util.h"
  66 #include "snprintf.h"
  67
  68 #define RFC850_STRFTIME "%A, %d-%b-%y %H:%M:%S GMT"
  69 #define RFC1123_STRFTIME "%a, %d %b %Y %H:%M:%S GMT"
  70
  71 static int make_month(const char *s);
  72 static int make_num(const char *s);
  73
  74 static char *month_names[12] =
  75 {
  76     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  77     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
  78 };
  79
  80
  81 static int
  82 make_num(const char *s)
  83 {
  84     if (*s >= '0' && *s <= '9')
  85         return 10 * (*s - '0') + *(s + 1) - '0';
  86     else
  87         return *(s + 1) - '0';
  88 }
  89
  90 static int
  91 make_month(const char *s)
  92 {
  93     int i;
  94     char month[3];
  95
  96     month[0] = xtoupper(*s);
  97     month[1] = xtolower(*(s + 1));
  98     month[2] = xtolower(*(s + 2));
  99
 100     for (i = 0; i < 12; i++)
 101         if (!strncmp(month_names[i], month, 3))
 102             return i;
 103     return 0;
 104 }
 105
 106
 107 time_t
 108 parse_rfc1123(const char *str)
 109 {
 110     const char *s;
 111     struct tm tm;
 112     time_t t;
 113
 114     if (!str)
 115         return -1;
 116
 117     memset(&tm, '\0', sizeof(struct tm));
 118     if ((s = strchr(str, ','))) {       /* Thursday, 10-Jun-93 01:29:59 GMT */
 119         s++;                    /* or: Thu, 10 Jan 1993 01:29:59 GMT */
 120         while (*s == ' ')
 121             s++;
 122         if (xisdigit(*s) && !xisdigit(*(s + 1)))        /* backoff if only one digit */
 123             s--;
 124         if (strchr(s, '-')) {   /* First format */
 125             if ((int) strlen(s) < 18)
 126                 return -1;
 127             tm.tm_mday = make_num(s);
 128             tm.tm_mon = make_month(s + 3);
 129             tm.tm_year = make_num(s + 7);
 130             /*
 131              * Y2K: Arjan de Vet <Arjan.deVet@adv.IAEhv.nl>
 132              * if tm.tm_year < 70, assume it's after the year 2000.
 133              */
 134             if (tm.tm_year < 70)
 135                 tm.tm_year += 100;
 136             tm.tm_hour = make_num(s + 10);
 137             tm.tm_min = make_num(s + 13);
 138             tm.tm_sec = make_num(s + 16);
 139         } else {                /* Second format */
 140             if ((int) strlen(s) < 20)
 141                 return -1;
 142             tm.tm_mday = make_num(s);
 143             tm.tm_mon = make_month(s + 3);
 144             tm.tm_year = (100 * make_num(s + 7) - 1900) + make_num(s + 9);
 145             tm.tm_hour = make_num(s + 12);
 146             tm.tm_min = make_num(s + 15);
 147             tm.tm_sec = make_num(s + 18);
 148
 149         }
 150     } else {                    /* Try the other format:        */
 151         s = str;                /* Wed Jun  9 01:29:59 1993 GMT */
 152         while (*s && *s == ' ')
 153             s++;
 154         if ((int) strlen(s) < 24)
 155             return -1;
 156         tm.tm_mday = make_num(s + 8);
 157         tm.tm_mon = make_month(s + 4);
 158         /* Y2K fix, richard.kettlewell@kewill.com */
 159         tm.tm_year = atoi(s + 20) - 1900;
 160         tm.tm_hour = make_num(s + 11);
 161         tm.tm_min = make_num(s + 14);
 162         tm.tm_sec = make_num(s + 17);
 163     }
 164     if (tm.tm_sec < 0 || tm.tm_sec > 59 ||
 165         tm.tm_min < 0 || tm.tm_min > 59 ||
 166         tm.tm_hour < 0 || tm.tm_hour > 23 ||
 167         tm.tm_mday < 1 || tm.tm_mday > 31 ||
 168         tm.tm_mon < 0 || tm.tm_mon > 11 ||
 169         tm.tm_year < 70 || tm.tm_year > 120) {
 170         return -1;
 171     }
 172     tm.tm_isdst = -1;
 173
 174 #ifdef HAVE_TIMEGM
 175     t = timegm(&tm);
 176 #elif HAVE_TM_GMTOFF
 177     t = mktime(&tm);
 178     {
 179         struct tm *local = localtime(&t);
 180         t += local->tm_gmtoff;
 181     }
 182 #else
 183     /* some systems do not have tm_gmtoff so we fake it */
 184     t = mktime(&tm);
 185     {
 186         time_t dst = 0;
 187 #if defined (_TIMEZONE)
 188 #elif defined (_timezone)
 189 #elif defined(_SQUID_AIX_)
 190 #else
 191         extern time_t timezone;
 192 #endif
 193         /*
 194          * The following assumes a fixed DST offset of 1 hour,
 195          * which is probably wrong.
 196          */
 197         if (tm.tm_isdst > 0)
 198             dst = -3600;
 199 #ifdef _timezone
 200         t -= (_timezone + dst);
 201 #else
 202         t -= (timezone + dst);
 203 #endif
 204     }
 205 #endif
 206     return t;
 207 }
 208
 209 const char *
 210 mkrfc1123(time_t t)
 211 {
 212     static char buf[128];
 213
 214     struct tm *gmt = gmtime(&t);
 215
 216     buf[0] = '\0';
 217     strftime(buf, 127, RFC1123_STRFTIME, gmt);
 218     return buf;
 219 }
 220
 221 const char *
 222 mkhttpdlogtime(const time_t * t)
 223 {
 224     static char buf[128];
 225
 226     struct tm *gmt = gmtime(t);
 227
 228 #ifndef USE_GMT
 229     int gmt_min, gmt_hour, gmt_yday, day_offset;
 230     size_t len;
 231     struct tm *lt;
 232     int min_offset;
 233
 234     /* localtime & gmtime may use the same static data */
 235     gmt_min = gmt->tm_min;
 236     gmt_hour = gmt->tm_hour;
 237     gmt_yday = gmt->tm_yday;
 238
 239     lt = localtime(t);
 240
 241     day_offset = lt->tm_yday - gmt_yday;
 242     /* wrap round on end of year */
 243     if (day_offset > 1)
 244         day_offset = -1;
 245     else if (day_offset < -1)
 246         day_offset = 1;
 247
 248     min_offset = day_offset * 1440 + (lt->tm_hour - gmt_hour) * 60
 249         + (lt->tm_min - gmt_min);
 250
 251     len = strftime(buf, 127 - 5, "%d/%b/%Y:%H:%M:%S ", lt);
 252     snprintf(buf + len, 128 - len, "%+03d%02d",
 253         (min_offset / 60) % 24,
 254         min_offset % 60);
 255 #else /* USE_GMT */
 256     buf[0] = '\0';
 257     strftime(buf, 127, "%d/%b/%Y:%H:%M:%S -000", gmt);
 258 #endif /* USE_GMT */
 259
 260     return buf;
 261 }
 262
 263 #if 0
 264 int
 265 main()
 266 {
 267     char *x;
 268     time_t t, pt;
 269
 270     t = time(NULL);
 271     x = mkrfc1123(t);
 272     printf("HTTP Time: %s\n", x);
 273
 274     pt = parse_rfc1123(x);
 275     printf("Parsed: %d vs. %d\n", pt, t);
 276 }
 277
 278 #endif