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 #include "assert.h"
  65
  66 #include "util.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 const char *month_names[12] = {
  75     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  76     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
  77 };
  78
  79
  80 static int
  81 make_num(const char *s)
  82 {
  83     if (*s >= '0' && *s <= '9')
  84         return 10 * (*s - '0') + *(s + 1) - '0';
  85     else
  86         return *(s + 1) - '0';
  87 }
  88
  89 static int
  90 make_month(const char *s)
  91 {
  92     int i;
  93     char month[3];
  94
  95     month[0] = xtoupper(*s);
  96     month[1] = xtolower(*(s + 1));
  97     month[2] = xtolower(*(s + 2));
  98
  99     for (i = 0; i < 12; i++)
 100         if (!strncmp(month_names[i], month, 3))
 101             return i;
 102     return -1;
 103 }
 104
 105 static int
 106 tmSaneValues(struct tm *tm)
 107 {
 108     if (tm->tm_sec < 0 || tm->tm_sec > 59)
 109         return 0;
 110     if (tm->tm_min < 0 || tm->tm_min > 59)
 111         return 0;
 112     if (tm->tm_hour < 0 || tm->tm_hour > 23)
 113         return 0;
 114     if (tm->tm_mday < 1 || tm->tm_mday > 31)
 115         return 0;
 116     if (tm->tm_mon < 0 || tm->tm_mon > 11)
 117         return 0;
 118     return 1;
 119 }
 120
 121 static struct tm *
 122             parse_date_elements(const char *day, const char *month, const char *year,
 123                                 const char *time, const char *zone) {
 124     static struct tm tm;
 125     char *t;
 126     memset(&tm, 0, sizeof(tm));
 127
 128     if (!day || !month || !year || !time)
 129         return NULL;
 130     tm.tm_mday = atoi(day);
 131     tm.tm_mon = make_month(month);
 132     if (tm.tm_mon < 0)
 133         return NULL;
 134     tm.tm_year = atoi(year);
 135     if (strlen(year) == 4)
 136         tm.tm_year -= 1900;
 137     else if (tm.tm_year < 70)
 138         tm.tm_year += 100;
 139     else if (tm.tm_year > 19000)
 140         tm.tm_year -= 19000;
 141     tm.tm_hour = make_num(time);
 142     t = strchr(time, ':');
 143     if (!t)
 144         return NULL;
 145     t++;
 146     tm.tm_min = atoi(t);
 147     t = strchr(t, ':');
 148     if (t)
 149         tm.tm_sec = atoi(t + 1);
 150     return tmSaneValues(&tm) ? &tm : NULL;
 151 }
 152
 153 static struct tm *
 154             parse_date(const char *str) {
 155     struct tm *tm;
 156     static char tmp[64];
 157     char *t;
 158     char *wday = NULL;
 159     char *day = NULL;
 160     char *month = NULL;
 161     char *year = NULL;
 162     char *time = NULL;
 163     char *zone = NULL;
 164
 165     xstrncpy(tmp, str, 64);
 166
 167     for (t = strtok(tmp, ", "); t; t = strtok(NULL, ", ")) {
 168         if (xisdigit(*t)) {
 169             if (!day) {
 170                 day = t;
 171                 t = strchr(t, '-');
 172                 if (t) {
 173                     *t++ = '\0';
 174                     month = t;
 175                     t = strchr(t, '-');
 176                     if (!t)
 177                         return NULL;
 178                     *t++ = '\0';
 179                     year = t;
 180                 }
 181             } else if (strchr(t, ':'))
 182                 time = t;
 183             else if (!year)
 184                 year = t;
 185         } else if (!wday)
 186             wday = t;
 187         else if (!month)
 188             month = t;
 189         else if (!zone)
 190             zone = t;
 191     }
 192     tm = parse_date_elements(day, month, year, time, zone);
 193
 194     return tm;
 195 }
 196
 197 time_t
 198 parse_rfc1123(const char *str)
 199 {
 200     struct tm *tm;
 201     time_t t;
 202     if (NULL == str)
 203         return -1;
 204     tm = parse_date(str);
 205     if (!tm)
 206         return -1;
 207     tm->tm_isdst = -1;
 208 #ifdef HAVE_TIMEGM
 209     t = timegm(tm);
 210 #elif HAVE_TM_TM_GMTOFF
 211     t = mktime(tm);
 212     if (t != -1) {
 213         struct tm *local = localtime(&t);
 214         t += local->tm_gmtoff;
 215     }
 216 #else
 217     /* some systems do not have tm_gmtoff so we fake it */
 218     t = mktime(tm);
 219     if (t != -1) {
 220         time_t dst = 0;
 221 #if defined (_TIMEZONE)
 222 #elif defined (_timezone)
 223 #elif defined(_SQUID_AIX_)
 224 #elif defined(_SQUID_CYGWIN_)
 225 #elif defined(_SQUID_MSWIN_)
 226 #elif defined(_SQUID_SGI_)
 227 #else
 228         extern long timezone;
 229 #endif
 230         /*
 231          * The following assumes a fixed DST offset of 1 hour,
 232          * which is probably wrong.
 233          */
 234         if (tm->tm_isdst > 0)
 235             dst = -3600;
 236 #if defined ( _timezone) || defined(_SQUID_WIN32_)
 237         t -= (_timezone + dst);
 238 #else
 239         t -= (timezone + dst);
 240 #endif
 241     }
 242 #endif
 243     return t;
 244 }
 245
 246 const char *
 247 mkrfc1123(time_t t)
 248 {
 249     static char buf[128];
 250
 251     struct tm *gmt = gmtime(&t);
 252
 253     buf[0] = '\0';
 254     strftime(buf, 127, RFC1123_STRFTIME, gmt);
 255     return buf;
 256 }
 257
 258 const char *
 259 mkhttpdlogtime(const time_t * t)
 260 {
 261     static char buf[128];
 262
 263     struct tm *gmt = gmtime(t);
 264
 265 #ifndef USE_GMT
 266     int gmt_min, gmt_hour, gmt_yday, day_offset;
 267     size_t len;
 268     struct tm *lt;
 269     int min_offset;
 270
 271     /* localtime & gmtime may use the same static data */
 272     gmt_min = gmt->tm_min;
 273     gmt_hour = gmt->tm_hour;
 274     gmt_yday = gmt->tm_yday;
 275
 276     lt = localtime(t);
 277
 278     day_offset = lt->tm_yday - gmt_yday;
 279     /* wrap round on end of year */
 280     if (day_offset > 1)
 281         day_offset = -1;
 282     else if (day_offset < -1)
 283         day_offset = 1;
 284
 285     min_offset = day_offset * 1440 + (lt->tm_hour - gmt_hour) * 60
 286                  + (lt->tm_min - gmt_min);
 287
 288     len = strftime(buf, 127 - 5, "%d/%b/%Y:%H:%M:%S ", lt);
 289     snprintf(buf + len, 128 - len, "%+03d%02d",
 290              (min_offset / 60) % 24,
 291              min_offset % 60);
 292 #else /* USE_GMT */
 293     buf[0] = '\0';
 294     strftime(buf, 127, "%d/%b/%Y:%H:%M:%S -000", gmt);
 295 #endif /* USE_GMT */
 296
 297     return buf;
 298 }
 299
 300 #if 0
 301 int
 302 main()
 303 {
 304     char *x;
 305     time_t t, pt;
 306
 307     t = time(NULL);
 308     x = mkrfc1123(t);
 309     printf("HTTP Time: %s\n", x);
 310
 311     pt = parse_rfc1123(x);
 312     printf("Parsed: %d vs. %d\n", pt, t);
 313 }
 314
 315 #endif