lib/rfc1123.c

   1
   2 /*
   3  * $Id: rfc1123.c,v 1.28 2001/01/12 00:37:13 wessels Exp $
   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 #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     s++;
 139     while (*s == ' ')
 140         s++;
 141     /* backup if month is only one digit */
 142     if (xisdigit(*s) && !xisdigit(*(s + 1)))
 143         s--;
 144     if (!strchr(s, '-'))
 145         return NULL;
 146     if ((int) strlen(s) < 18)
 147         return NULL;
 148     memset(&tm, '\0', sizeof(tm));
 149     tm.tm_mday = make_num(s);
 150     tm.tm_mon = make_month(s + 3);
 151     tm.tm_year = make_num(s + 7);
 152     /*
 153      * Y2K: Arjan de Vet <Arjan.deVet@adv.IAEhv.nl>
 154      * if tm.tm_year < 70, assume it's after the year 2000.
 155      */
 156     if (tm.tm_year < 70)
 157         tm.tm_year += 100;
 158     tm.tm_hour = make_num(s + 10);
 159     tm.tm_min = make_num(s + 13);
 160     tm.tm_sec = make_num(s + 16);
 161     return tmSaneValues(&tm) ? &tm : NULL;
 162 }
 163
 164 static struct tm *
 165 parse_date2(const char *str)
 166 {
 167     /* Thu, 10 Jan 1993 01:29:59 GMT */
 168     const char *s;
 169     static struct tm tm;
 170     assert(NULL != str);
 171     memset(&tm, '\0', sizeof(struct tm));
 172     s = strchr(str, ',');
 173     if (NULL == s)
 174         return NULL;
 175     s++;
 176     while (*s == ' ')
 177         s++;
 178     /* backup if month is only one digit */
 179     if (xisdigit(*s) && !xisdigit(*(s + 1)))
 180         s--;
 181     if (strchr(s, '-'))
 182         return NULL;
 183     if ((int) strlen(s) < 20)
 184         return NULL;
 185     memset(&tm, '\0', sizeof(tm));
 186     tm.tm_mday = make_num(s);
 187     tm.tm_mon = make_month(s + 3);
 188     tm.tm_year = (100 * make_num(s + 7) - 1900) + make_num(s + 9);
 189     tm.tm_hour = make_num(s + 12);
 190     tm.tm_min = make_num(s + 15);
 191     tm.tm_sec = make_num(s + 18);
 192     return tmSaneValues(&tm) ? &tm : NULL;
 193 }
 194
 195 static struct tm *
 196 parse_date3(const char *str)
 197 {
 198     /* Wed Jun  9 01:29:59 1993 GMT */
 199     static struct tm tm;
 200     char *s;
 201     static char buf[128];
 202     while (*str && *str == ' ')
 203         str++;
 204     xstrncpy(buf, str, 128);
 205     if (NULL == (s = strtok(buf, w_space)))
 206         return NULL;
 207     if (NULL == (s = strtok(NULL, w_space)))
 208         return NULL;
 209     tm.tm_mon = make_month(s);
 210     if (NULL == (s = strtok(NULL, w_space)))
 211         return NULL;
 212     tm.tm_mday = atoi(s);
 213     if (NULL == (s = strtok(NULL, ":")))
 214         return NULL;
 215     tm.tm_hour = atoi(s);
 216     if (NULL == (s = strtok(NULL, ":")))
 217         return NULL;
 218     tm.tm_min = atoi(s);
 219     if (NULL == (s = strtok(NULL, w_space)))
 220         return NULL;
 221     tm.tm_sec = atoi(s);
 222     if (NULL == (s = strtok(NULL, w_space)))
 223         return NULL;
 224     /* Y2K fix, richard.kettlewell@kewill.com */
 225     tm.tm_year = atoi(s) - 1900;
 226     return tmSaneValues(&tm) ? &tm : NULL;
 227 }
 228
 229 time_t
 230 parse_rfc1123(const char *str)
 231 {
 232     struct tm *tm;
 233     time_t t;
 234     if (NULL == str)
 235         return -1;
 236     tm = parse_date1(str);
 237     if (NULL == tm) {
 238         tm = parse_date2(str);
 239         if (NULL == tm) {
 240             tm = parse_date3(str);
 241             if (NULL == tm)
 242                 return -1;
 243         }
 244     }
 245     tm->tm_isdst = -1;
 246 #ifdef HAVE_TIMEGM
 247     t = timegm(tm);
 248 #elif HAVE_TM_GMTOFF
 249     t = mktime(tm);
 250     {
 251         struct tm *local = localtime(&t);
 252         t += local->tm_gmtoff;
 253     }
 254 #else
 255     /* some systems do not have tm_gmtoff so we fake it */
 256     t = mktime(tm);
 257     {
 258         time_t dst = 0;
 259 #if defined (_TIMEZONE)
 260 #elif defined (_timezone)
 261 #elif defined(_SQUID_AIX_)
 262 #elif defined(_SQUID_CYGWIN_)
 263 #else
 264         extern time_t timezone;
 265 #endif
 266         /*
 267          * The following assumes a fixed DST offset of 1 hour,
 268          * which is probably wrong.
 269          */
 270         if (tm->tm_isdst > 0)
 271             dst = -3600;
 272 #if defined ( _timezone) || defined(_SQUID_CYGWIN_)
 273         t -= (_timezone + dst);
 274 #else
 275         t -= (timezone + dst);
 276 #endif
 277     }
 278 #endif
 279     return t;
 280 }
 281
 282 const char *
 283 mkrfc1123(time_t t)
 284 {
 285     static char buf[128];
 286
 287     struct tm *gmt = gmtime(&t);
 288
 289     buf[0] = '\0';
 290     strftime(buf, 127, RFC1123_STRFTIME, gmt);
 291     return buf;
 292 }
 293
 294 const char *
 295 mkhttpdlogtime(const time_t * t)
 296 {
 297     static char buf[128];
 298
 299     struct tm *gmt = gmtime(t);
 300
 301 #ifndef USE_GMT
 302     int gmt_min, gmt_hour, gmt_yday, day_offset;
 303     size_t len;
 304     struct tm *lt;
 305     int min_offset;
 306
 307     /* localtime & gmtime may use the same static data */
 308     gmt_min = gmt->tm_min;
 309     gmt_hour = gmt->tm_hour;
 310     gmt_yday = gmt->tm_yday;
 311
 312     lt = localtime(t);
 313
 314     day_offset = lt->tm_yday - gmt_yday;
 315     /* wrap round on end of year */
 316     if (day_offset > 1)
 317         day_offset = -1;
 318     else if (day_offset < -1)
 319         day_offset = 1;
 320
 321     min_offset = day_offset * 1440 + (lt->tm_hour - gmt_hour) * 60
 322         + (lt->tm_min - gmt_min);
 323
 324     len = strftime(buf, 127 - 5, "%d/%b/%Y:%H:%M:%S ", lt);
 325     snprintf(buf + len, 128 - len, "%+03d%02d",
 326         (min_offset / 60) % 24,
 327         min_offset % 60);
 328 #else /* USE_GMT */
 329     buf[0] = '\0';
 330     strftime(buf, 127, "%d/%b/%Y:%H:%M:%S -000", gmt);
 331 #endif /* USE_GMT */
 332
 333     return buf;
 334 }
 335
 336 #if 0
 337 int
 338 main()
 339 {
 340     char *x;
 341     time_t t, pt;
 342
 343     t = time(NULL);
 344     x = mkrfc1123(t);
 345     printf("HTTP Time: %s\n", x);
 346
 347     pt = parse_rfc1123(x);
 348     printf("Parsed: %d vs. %d\n", pt, t);
 349 }
 350
 351 #endif