lib/rfc1123.c

   1
   2 /*
   3  * $Id$
   4  *
   5  * DEBUG:
   6  * AUTHOR: Harvest Derived
   7  *
   8  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   9  * ----------------------------------------------------------
  10  *
  11  *  Squid is the result of efforts by numerous individuals from
  12  *  the Internet community; see the CONTRIBUTORS file for full
  13  *  details.   Many organizations have provided support for Squid's
  14  *  development; see the SPONSORS file for full details.  Squid is
  15  *  Copyrighted (C) 2001 by the Regents of the University of
  16  *  California; see the COPYRIGHT file for full details.  Squid
  17  *  incorporates software developed and/or copyrighted by other
  18  *  sources; see the 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
  67 #define RFC850_STRFTIME "%A, %d-%b-%y %H:%M:%S GMT"
  68 #define RFC1123_STRFTIME "%a, %d %b %Y %H:%M:%S GMT"
  69
  70 static int make_month(const char *s);
  71 static int make_num(const char *s);
  72
  73 static const char *month_names[12] = {
  74     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  75     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
  76 };
  77
  78
  79 static int
  80 make_num(const char *s)
  81 {
  82     if (*s >= '0' && *s <= '9')
  83         return 10 * (*s - '0') + *(s + 1) - '0';
  84     else
  85         return *(s + 1) - '0';
  86 }
  87
  88 static int
  89 make_month(const char *s)
  90 {
  91     int i;
  92     char month[3];
  93
  94     month[0] = xtoupper(*s);
  95     month[1] = xtolower(*(s + 1));
  96     month[2] = xtolower(*(s + 2));
  97
  98     for (i = 0; i < 12; i++)
  99         if (!strncmp(month_names[i], month, 3))
 100             return i;
 101     return -1;
 102 }
 103
 104 static int
 105 tmSaneValues(struct tm *tm)
 106 {
 107     if (tm->tm_sec < 0 || tm->tm_sec > 59)
 108         return 0;
 109     if (tm->tm_min < 0 || tm->tm_min > 59)
 110         return 0;
 111     if (tm->tm_hour < 0 || tm->tm_hour > 23)
 112         return 0;
 113     if (tm->tm_mday < 1 || tm->tm_mday > 31)
 114         return 0;
 115     if (tm->tm_mon < 0 || tm->tm_mon > 11)
 116         return 0;
 117     return 1;
 118 }
 119
 120 static struct tm *
 121 parse_date_elements(const char *day, const char *month, const char *year,
 122                     const char *time, const char *zone) {
 123     static struct tm tm;
 124     char *t;
 125     memset(&tm, 0, sizeof(tm));
 126
 127     if (!day || !month || !year || !time)
 128         return NULL;
 129     tm.tm_mday = atoi(day);
 130     tm.tm_mon = make_month(month);
 131     if (tm.tm_mon < 0)
 132         return NULL;
 133     tm.tm_year = atoi(year);
 134     if (strlen(year) == 4)
 135         tm.tm_year -= 1900;
 136     else if (tm.tm_year < 70)
 137         tm.tm_year += 100;
 138     else if (tm.tm_year > 19000)
 139         tm.tm_year -= 19000;
 140     tm.tm_hour = make_num(time);
 141     t = strchr(time, ':');
 142     if (!t)
 143         return NULL;
 144     t++;
 145     tm.tm_min = atoi(t);
 146     t = strchr(t, ':');
 147     if (t)
 148         tm.tm_sec = atoi(t + 1);
 149     return tmSaneValues(&tm) ? &tm : NULL;
 150 }
 151
 152 static struct tm *
 153 parse_date(const char *str) {
 154     struct tm *tm;
 155     static char tmp[64];
 156     char *t;
 157     char *wday = NULL;
 158     char *day = NULL;
 159     char *month = NULL;
 160     char *year = NULL;
 161     char *time = NULL;
 162     char *zone = NULL;
 163
 164     xstrncpy(tmp, str, 64);
 165
 166     for (t = strtok(tmp, ", "); t; t = strtok(NULL, ", ")) {
 167         if (xisdigit(*t)) {
 168             if (!day) {
 169                 day = t;
 170                 t = strchr(t, '-');
 171                 if (t) {
 172                     *t++ = '\0';
 173                     month = t;
 174                     t = strchr(t, '-');
 175                     if (!t)
 176                         return NULL;
 177                     *t++ = '\0';
 178                     year = t;
 179                 }
 180             } else if (strchr(t, ':'))
 181                 time = t;
 182             else if (!year)
 183                 year = t;
 184         } else if (!wday)
 185             wday = t;
 186         else if (!month)
 187             month = t;
 188         else if (!zone)
 189             zone = t;
 190     }
 191     tm = parse_date_elements(day, month, year, time, zone);
 192
 193     return tm;
 194 }
 195
 196 time_t
 197 parse_rfc1123(const char *str)
 198 {
 199     struct tm *tm;
 200     time_t t;
 201     if (NULL == str)
 202         return -1;
 203     tm = parse_date(str);
 204     if (!tm)
 205         return -1;
 206     tm->tm_isdst = -1;
 207 #ifdef HAVE_TIMEGM
 208     t = timegm(tm);
 209 #elif HAVE_TM_TM_GMTOFF
 210     t = mktime(tm);
 211     if (t != -1) {
 212         struct tm *local = localtime(&t);
 213         t += local->tm_gmtoff;
 214     }
 215 #else
 216     /* some systems do not have tm_gmtoff so we fake it */
 217     t = mktime(tm);
 218     if (t != -1) {
 219         time_t dst = 0;
 220 #if defined (_TIMEZONE)
 221 #elif defined (_timezone)
 222 #elif defined(_SQUID_AIX_)
 223 #elif defined(_SQUID_CYGWIN_)
 224 #elif defined(_SQUID_MSWIN_)
 225 #elif defined(_SQUID_SGI_)
 226 #else
 227     extern long timezone;
 228 #endif
 229         /*
 230          * The following assumes a fixed DST offset of 1 hour,
 231          * which is probably wrong.
 232          */
 233         if (tm->tm_isdst > 0)
 234             dst = -3600;
 235 #if defined ( _timezone) || defined(_SQUID_WIN32_)
 236         t -= (_timezone + dst);
 237 #else
 238     t -= (timezone + dst);
 239 #endif
 240     }
 241 #endif
 242     return t;
 243 }
 244
 245 const char *
 246 mkrfc1123(time_t t)
 247 {
 248     static char buf[128];
 249
 250     struct tm *gmt = gmtime(&t);
 251
 252     buf[0] = '\0';
 253     strftime(buf, 127, RFC1123_STRFTIME, gmt);
 254     return buf;
 255 }
 256
 257 const char *
 258 mkhttpdlogtime(const time_t * t)
 259 {
 260     static char buf[128];
 261
 262     struct tm *gmt = gmtime(t);
 263
 264 #ifndef USE_GMT
 265     int gmt_min, gmt_hour, gmt_yday, day_offset;
 266     size_t len;
 267     struct tm *lt;
 268     int min_offset;
 269
 270     /* localtime & gmtime may use the same static data */
 271     gmt_min = gmt->tm_min;
 272     gmt_hour = gmt->tm_hour;
 273     gmt_yday = gmt->tm_yday;
 274
 275     lt = localtime(t);
 276
 277     day_offset = lt->tm_yday - gmt_yday;
 278     /* wrap round on end of year */
 279     if (day_offset > 1)
 280         day_offset = -1;
 281     else if (day_offset < -1)
 282         day_offset = 1;
 283
 284     min_offset = day_offset * 1440 + (lt->tm_hour - gmt_hour) * 60
 285                  + (lt->tm_min - gmt_min);
 286
 287     len = strftime(buf, 127 - 5, "%d/%b/%Y:%H:%M:%S ", lt);
 288     snprintf(buf + len, 128 - len, "%+03d%02d",
 289              (min_offset / 60) % 24,
 290              min_offset % 60);
 291 #else /* USE_GMT */
 292     buf[0] = '\0';
 293     strftime(buf, 127, "%d/%b/%Y:%H:%M:%S -000", gmt);
 294 #endif /* USE_GMT */
 295
 296     return buf;
 297 }
 298
 299 #if 0
 300 int
 301 main()
 302 {
 303     char *x;
 304     time_t t, pt;
 305
 306     t = time(NULL);
 307     x = mkrfc1123(t);
 308     printf("HTTP Time: %s\n", x);
 309
 310     pt = parse_rfc1123(x);
 311     printf("Parsed: %d vs. %d\n", pt, t);
 312 }
 313
 314 #endif