lib/rfc1123.c

   1
   2 /*
   3  * $Id: rfc1123.c,v 1.26 2000/11/07 23:37:35 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 #include "assert.h"
  65
  66 #include "util.h"
  67 #include "snprintf.h"
  68
  69 #define RFC850_STRFTIME "%A, %d-%b-%y %H:%M:%S GMT"
  70 #define RFC1123_STRFTIME "%a, %d %b %Y %H:%M:%S GMT"
  71
  72 static const char *const w_space = " \t\r\n";
  73
  74 static int make_month(const char *s);
  75 static int make_num(const char *s);
  76
  77 static char *month_names[12] =
  78 {
  79     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  80     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
  81 };
  82
  83
  84 static int
  85 make_num(const char *s)
  86 {
  87     if (*s >= '0' && *s <= '9')
  88         return 10 * (*s - '0') + *(s + 1) - '0';
  89     else
  90         return *(s + 1) - '0';
  91 }
  92
  93 static int
  94 make_month(const char *s)
  95 {
  96     int i;
  97     char month[3];
  98
  99     month[0] = xtoupper(*s);
 100     month[1] = xtolower(*(s + 1));
 101     month[2] = xtolower(*(s + 2));
 102
 103     for (i = 0; i < 12; i++)
 104         if (!strncmp(month_names[i], month, 3))
 105             return i;
 106     return 0;
 107 }
 108
 109 static int
 110 tmSaneValues(struct tm *tm)
 111 {
 112     if (tm->tm_sec < 0 || tm->tm_sec > 59)
 113         return 0;
 114     if (tm->tm_min < 0 || tm->tm_min > 59)
 115         return 0;
 116     if (tm->tm_hour < 0 || tm->tm_hour > 23)
 117         return 0;
 118     if (tm->tm_mday < 1 || tm->tm_mday > 31)
 119         return 0;
 120     if (tm->tm_mon < 0 || tm->tm_mon > 11)
 121         return 0;
 122     if (tm->tm_year < 70 || tm->tm_year > 120)
 123         return 0;
 124     return 1;
 125 }
 126
 127 static struct tm *
 128 parse_date1(const char *str)
 129 {
 130     /* Thursday, 10-Jun-93 01:29:59 GMT */
 131     const char *s;
 132     static struct tm tm;
 133     assert(NULL != str);
 134     memset(&tm, '\0', sizeof(struct tm));
 135     s = strchr(str, ',');
 136     if (NULL == s)
 137         return NULL;
 138     while (*s == ' ')
 139         s++;
 140     /* backup if month is only one digit */
 141     if (xisdigit(*s) && !xisdigit(*(s + 1)))
 142         s--;
 143     if (!strchr(s, '-'))
 144         return NULL;
 145     if ((int) strlen(s) < 18)
 146         return NULL;
 147     memset(&tm, '\0', sizeof(tm));
 148     tm.tm_mday = make_num(s);
 149     tm.tm_mon = make_month(s + 3);
 150     tm.tm_year = make_num(s + 7);
 151     /*
 152      * Y2K: Arjan de Vet <Arjan.deVet@adv.IAEhv.nl>
 153      * if tm.tm_year < 70, assume it's after the year 2000.
 154      */
 155     if (tm.tm_year < 70)
 156         tm.tm_year += 100;
 157     tm.tm_hour = make_num(s + 10);
 158     tm.tm_min = make_num(s + 13);
 159     tm.tm_sec = make_num(s + 16);
 160     return tmSaneValues(&tm) ? &tm : NULL;
 161 }
 162
 163 static struct tm *
 164 parse_date2(const char *str)
 165 {
 166     /* Thu, 10 Jan 1993 01:29:59 GMT */
 167     const char *s;
 168     struct tm tm;
 169     assert(NULL != str);
 170     memset(&tm, '\0', sizeof(struct tm));
 171     s = strchr(str, ',');
 172     if (NULL == s)
 173         return NULL;
 174     while (*s == ' ')
 175         s++;
 176     /* backup if month is only one digit */
 177     if (xisdigit(*s) && !xisdigit(*(s + 1)))
 178         s--;
 179     if (strchr(s, '-'))
 180         return NULL;
 181     if ((int) strlen(s) < 20)
 182         return NULL;
 183     memset(&tm, '\0', sizeof(tm));
 184     tm.tm_mday = make_num(s);
 185     tm.tm_mon = make_month(s + 3);
 186     tm.tm_year = (100 * make_num(s + 7) - 1900) + make_num(s + 9);
 187     tm.tm_hour = make_num(s + 12);
 188     tm.tm_min = make_num(s + 15);
 189     tm.tm_sec = make_num(s + 18);
 190     return tmSaneValues(&tm) ? &tm : NULL;
 191 }
 192
 193 static struct tm *
 194 parse_date3(const char *str)
 195 {
 196     /* Wed Jun  9 01:29:59 1993 GMT */
 197     static struct tm tm;
 198     char *s;
 199     static char buf[128];
 200     while (*str && *str == ' ')
 201         str++;
 202     xstrncpy(buf, str, 128);
 203     if (NULL == (s = strtok(buf, w_space)))
 204         return NULL;
 205     if (NULL == (s = strtok(NULL, w_space)))
 206         return NULL;
 207     tm.tm_mon = make_month(s);
 208     if (NULL == (s = strtok(NULL, w_space)))
 209         return NULL;
 210     tm.tm_mday = atoi(s);
 211     if (NULL == (s = strtok(NULL, ":")))
 212         return NULL;
 213     tm.tm_hour = atoi(s);
 214     if (NULL == (s = strtok(NULL, ":")))
 215         return NULL;
 216     tm.tm_min = atoi(s);
 217     if (NULL == (s = strtok(NULL, w_space)))
 218         return NULL;
 219     tm.tm_sec = atoi(s);
 220     if (NULL == (s = strtok(NULL, w_space)))
 221         return NULL;
 222     /* Y2K fix, richard.kettlewell@kewill.com */
 223     tm.tm_year = atoi(s) - 1900;
 224     return tmSaneValues(&tm) ? &tm : NULL;
 225 }
 226
 227 time_t
 228 parse_rfc1123(const char *str)
 229 {
 230     struct tm *tm;
 231     time_t t;
 232     if (NULL == str)
 233         return -1;
 234     tm = parse_date1(str);
 235     if (NULL == tm) {
 236         tm = parse_date2(str);
 237         if (NULL == tm) {
 238             tm = parse_date3(str);
 239             if (NULL == tm)
 240                 return -1;
 241         }
 242     }
 243     tm->tm_isdst = -1;
 244 #ifdef HAVE_TIMEGM
 245     t = timegm(tm);
 246 #elif HAVE_TM_GMTOFF
 247     t = mktime(tm);
 248     {
 249         struct tm *local = localtime(&t);
 250         t += local->tm_gmtoff;
 251     }
 252 #else
 253     /* some systems do not have tm_gmtoff so we fake it */
 254     t = mktime(tm);
 255     {
 256         time_t dst = 0;
 257 #if defined (_TIMEZONE)
 258 #elif defined (_timezone)
 259 #elif defined(_SQUID_AIX_)
 260 #elif defined(_SQUID_CYGWIN_)
 261 #else
 262         extern time_t timezone;
 263 #endif
 264         /*
 265          * The following assumes a fixed DST offset of 1 hour,
 266          * which is probably wrong.
 267          */
 268         if (tm->tm_isdst > 0)
 269             dst = -3600;
 270 #if defined ( _timezone) || defined(_SQUID_CYGWIN_)
 271         t -= (_timezone + dst);
 272 #else
 273         t -= (timezone + dst);
 274 #endif
 275     }
 276 #endif
 277     return t;
 278 }
 279
 280 const char *
 281 mkrfc1123(time_t t)
 282 {
 283     static char buf[128];
 284
 285     struct tm *gmt = gmtime(&t);
 286
 287     buf[0] = '\0';
 288     strftime(buf, 127, RFC1123_STRFTIME, gmt);
 289     return buf;
 290 }
 291
 292 const char *
 293 mkhttpdlogtime(const time_t * t)
 294 {
 295     static char buf[128];
 296
 297     struct tm *gmt = gmtime(t);
 298
 299 #ifndef USE_GMT
 300     int gmt_min, gmt_hour, gmt_yday, day_offset;
 301     size_t len;
 302     struct tm *lt;
 303     int min_offset;
 304
 305     /* localtime & gmtime may use the same static data */
 306     gmt_min = gmt->tm_min;
 307     gmt_hour = gmt->tm_hour;
 308     gmt_yday = gmt->tm_yday;
 309
 310     lt = localtime(t);
 311
 312     day_offset = lt->tm_yday - gmt_yday;
 313     /* wrap round on end of year */
 314     if (day_offset > 1)
 315         day_offset = -1;
 316     else if (day_offset < -1)
 317         day_offset = 1;
 318
 319     min_offset = day_offset * 1440 + (lt->tm_hour - gmt_hour) * 60
 320         + (lt->tm_min - gmt_min);
 321
 322     len = strftime(buf, 127 - 5, "%d/%b/%Y:%H:%M:%S ", lt);
 323     snprintf(buf + len, 128 - len, "%+03d%02d",
 324         (min_offset / 60) % 24,
 325         min_offset % 60);
 326 #else /* USE_GMT */
 327     buf[0] = '\0';
 328     strftime(buf, 127, "%d/%b/%Y:%H:%M:%S -000", gmt);
 329 #endif /* USE_GMT */
 330
 331     return buf;
 332 }
 333
 334 #if 0
 335 int
 336 main()
 337 {
 338     char *x;
 339     time_t t, pt;
 340
 341     t = time(NULL);
 342     x = mkrfc1123(t);
 343     printf("HTTP Time: %s\n", x);
 344
 345     pt = parse_rfc1123(x);
 346     printf("Parsed: %d vs. %d\n", pt, t);
 347 }
 348
 349 #endif