krfcdate.cpp

来自「将konqueror浏览器移植到ARM9 2410中」· C++ 代码 · 共 321 行

/*
 *
 *  This file is part of the KDE libraries
 *  Copyright (c) 2000 Waldo Bastian <[e-mail]>
 *
 * $Id: krfcdate.cpp,v 1.9.2.2 2001/10/08 23:34:03 waba Exp $
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Library General Public
 *  License version 2 as published by the Free Software Foundation.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Library General Public License for more details.
 *
 *  You should have received a copy of the GNU Library General Public License
 *  along with this library; see the file COPYING.LIB.  If not, write to
 *  the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 *  Boston, MA 02111-1307, USA.
 **/

#include <config.h>

#include <sys/param.h>
#include <ctype.h>
#include <stdlib.h>

#include <krfcdate.h>

static unsigned int ymdhms_to_seconds(int year, int mon, int day, int hour, int minute, int second)
{
    unsigned int ret = (day - 32075)       /* days */
            + 1461L * (year + 4800L + (mon - 14) / 12) / 4
            + 367 * (mon - 2 - (mon - 14) / 12 * 12) / 12
            - 3 * ((year + 4900L + (mon - 14) / 12) / 100) / 4
            - 2440588;
    ret = 24*ret + hour;     /* hours   */
    ret = 60*ret + minute;   /* minutes */
    ret = 60*ret + second;   /* seconds */

    return ret;
}

static const char haystack[37]="janfebmaraprmayjunjulaugsepoctnovdec";

// we follow the recommendation of rfc2822 to consider all
// obsolete time zones not listed here equivalent to "-0000"
static const struct {
    const char *tzName;
    int tzOffset;
} known_zones[] = {
    { "UT", 0 },
    { "GMT", 0 },
    { "EST", -300 },
    { "EDT", -240 },
    { "CST", -360 },
    { "CDT", -300 },
    { "MST", -420 },
    { "MDT", -360 },
    { "PST", -480 },
    { "PDT", -420 },
    { 0, 0 }
};

time_t
KRFCDate::parseDate(const QString &_date)
{
     // This parse a date in the form:
     //     Wednesday, 09-Nov-99 23:12:40 GMT
     // or
     //     Sat, 01-Jan-2000 08:00:00 GMT
     // or
     //     Sat, 01 Jan 2000 08:00:00 GMT
     // or
     //     01 Jan 99 22:00 +0100    (exceptions in rfc822/rfc2822)
     //
     // We ignore the weekday
     //
     time_t result = 0;
     int offset = 0;
     char *newPosStr;
     const char *dateString = _date.latin1();
     int day = 0;
     char monthStr[4];
     int month = 0;
     int year = 0;
     int hour = 0;
     int minute = 0;
     int second = 0;

     while(*dateString && !isdigit(*dateString))
     	dateString++;

     if (!*dateString)
     	return result;  // Invalid date

     // ' 09-Nov-99 23:12:40 GMT'
     day = strtol(dateString, &newPosStr, 10);
     dateString = newPosStr;

     if ((day < 1) || (day > 31))
     	return result; // Invalid date;
     if (!*dateString)
     	return result;  // Invalid date

     if (*dateString == '-')
     	dateString++;

     while(*dateString && isspace(*dateString))
     	dateString++;

     for(int i=0; i < 3;i++)
     {
         if (!*dateString || (*dateString == '-') || isspace(*dateString))
              return result;  // Invalid date
         monthStr[i] = tolower(*dateString++);
     }
     monthStr[3] = '\0';

     newPosStr = (char*)strstr(haystack, monthStr);

     if (!newPosStr)
     	return result;  // Invalid date

     month = (newPosStr-haystack)/3; // Jan=00, Feb=01, Mar=02, ..

     if ((month < 0) || (month > 11))
     	return result;  // Invalid date

     while(*dateString && (*dateString != '-') && !isspace(*dateString))
     	dateString++;

     if (!*dateString)
     	return result;  // Invalid date

     // '-99 23:12:40 GMT'
     if ((*dateString != '-') && !isspace(*dateString))
     	return result;  // Invalid date
     dateString++;

     // '99 23:12:40 GMT'
     year = strtol(dateString, &newPosStr, 10);
     dateString = newPosStr;

     // Y2K: Solve 2 digit years
     if ((year >= 0) && (year < 50))
         year += 2000;

     if ((year >= 50) && (year < 100))
         year += 1900;  // Y2K

     if ((year < 1900) || (year > 2500))
     	return result; // Invalid date

     // Don't fail if the time is missing.
     if (*dateString)
     {
        // ' 23:12:40 GMT'
        if (!isspace(*dateString++))
           return result;  // Invalid date

        hour = strtol(dateString, &newPosStr, 10);
        dateString = newPosStr;

        if ((hour < 0) || (hour > 23))
           return result; // Invalid date

        if (!*dateString)
           return result;  // Invalid date

        // ':12:40 GMT'
        if (*dateString++ != ':')
           return result;  // Invalid date

        minute = strtol(dateString, &newPosStr, 10);
        dateString = newPosStr;

        if ((minute < 0) || (minute > 59))
           return result; // Invalid date

        if (!*dateString)
           return result;  // Invalid date

        // ':40 GMT'
        if (*dateString != ':' && !isspace(*dateString))
           return result;  // Invalid date

        // seconds are optional in rfc822 + rfc2822
        if (*dateString ==':') {
           dateString++;

           second = strtol(dateString, &newPosStr, 10);
           dateString = newPosStr;

           if ((second < 0) || (second > 59))
              return result; // Invalid date
        } else {
           dateString++;
        }

        while(*dateString && isspace(*dateString))
           dateString++;
     }

     // don't fail if the time zone is missing, some
     // broken mail-/news-clients omit the time zone
     if (*dateString) {

        if ((*dateString == '+') || (*dateString == '-')) {
           offset = strtol(dateString, &newPosStr, 10);

           if ((offset < -9959) || (offset > 9959))
              return result; // Invalid date

           int sgn = (offset < 0)? -1:1;
           offset = abs(offset);
           offset = ((offset / 100)*60 + (offset % 100))*sgn;
        } else {
           for (int i=0; known_zones[i].tzName != 0; i++) {
              if (0 == strncasecmp(dateString, known_zones[i].tzName, strlen(known_zones[i].tzName))) {
                 offset = known_zones[i].tzOffset;
                 break;
              }
           }
        }
     }
     if (sizeof(time_t) == 4)
     {
         if ((time_t)-1 < 0)
         {
            if (year >= 2038)
            {
               year = 2038;
               month = 0;
               day = 1;
               hour = 0;
               minute = 0;
               second = 0;
            }
         }
         else
         {
            if (year >= 2115)
            {
               year = 2115;
               month = 0;
               day = 1;
               hour = 0;
               minute = 0;
               second = 0;
            }
         }
     }

     result = ymdhms_to_seconds(year, month+1, day, hour, minute, second);

     // avoid negative time values
     if ((offset > 0) && (offset > result))
        offset = 0;

     result -= offset*60;

     // If epoch 0 return epoch +1 which is Thu, 01-Jan-70 00:00:01 GMT
     // This is so that parse error and valid epoch 0 return values won't
     // be the same for sensitive applications...     
     if (result < 1) result = 1;

     return result;
}


int KRFCDate::localUTCOffset()
{
  time_t timeNow = time((time_t*) 0);

  tm *tM = gmtime(&timeNow);
  unsigned int timeUTC = ymdhms_to_seconds(tM->tm_year+1900, tM->tm_mon+1, tM->tm_mday,
                                           tM->tm_hour, tM->tm_min, tM->tm_sec);

  tM = localtime(&timeNow);
  unsigned int timeLocal = ymdhms_to_seconds(tM->tm_year+1900, tM->tm_mon+1, tM->tm_mday,
                                             tM->tm_hour, tM->tm_min, tM->tm_sec);

  return ((int)(timeLocal-timeUTC))/60;
}


static const char *day_names[] = {
    "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};

static const char *month_names[] = {
    "Jan", "Feb", "Mar", "Apr", "May", "Jun",
    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
};


QCString KRFCDate::rfc2822DateString(time_t utcTime, int utcOffset)
{
    utcTime += utcOffset * 60;
    tm *tM = gmtime(&utcTime);
    char sgn = (utcOffset < 0) ? '-' : '+';
    int z = (utcOffset < 0) ? -utcOffset : utcOffset;
    QCString dateStr;

    dateStr.sprintf("%s, %02d %s %04d %02d:%02d:%02d %c%02d%02d",
                    day_names[tM->tm_wday], tM->tm_mday,
                    month_names[tM->tm_mon], tM->tm_year+1900,
                    tM->tm_hour, tM->tm_min, tM->tm_sec,
                    sgn, z/60%24, z%60);

    return dateStr;
}


QCString KRFCDate::rfc2822DateString(time_t utcTime)
{
    return rfc2822DateString(utcTime, localUTCOffset());
}