/* * Copyright (C) 2001-2003 by egnite Software GmbH. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the copyright holders nor the names of * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * For additional information see http://www.ethernut.de/ * * Portions of the following functions are derived from material which is * Copyright (c) 1985 by Microsoft Corporation. All rights are reserved. */ /* * $Log$ * Revision 1.6 2009/01/17 15:37:52 haraldkipp * Added some NUTASSERT macros to check function parameters. * * Revision 1.5 2008/08/11 06:59:40 haraldkipp * BSD types replaced by stdint types (feature request #1282721). * * Revision 1.4 2004/10/14 16:43:00 drsung * Fixed compiler warning "comparison between signed and unsigned" * * Revision 1.3 2003/12/19 22:26:37 drsung * Dox written. * * Revision 1.2 2003/11/26 11:14:32 haraldkipp * Portability issues * * Revision 1.1 2003/11/24 18:07:37 drsung * first release * * */ #include #include #include "ctime.h" #include #define __need_NULL #include #define LONG_MAX 2147483647L /*! * \addtogroup xgCrtTime * @{ */ /*! * \brief Convert a time value and correct for the local time zone. * * Thread safe version of \b localtime. See ::localtime for more information. * * \param timer Pointer to stored time. * \param ptm Pointer to structure ::tm where the converted time is stored. * \return Always return 0. * */ int localtime_r(const time_t * timer, tm * ptm) { long ltime; NUTASSERT(timer != NULL); if ((*timer > (time_t)(3 * _DAY_SEC)) && (*timer < (time_t)(LONG_MAX - 3 * _DAY_SEC))) { /* * The date does not fall within the first three, or last * three, representable days of the Epoch. Therefore, there * is no possibility of overflowing or underflowing the * time_t representation as we compensate for timezone and * Daylight Savings Time. */ ltime = (long) *timer - _timezone; gmtime_r((time_t *) & ltime, ptm); /* * Check and adjust for Daylight Saving Time. */ if (_daylight && _isindst(ptm)) { ltime -= _dstbias; gmtime_r((time_t *) & ltime, ptm); ptm->tm_isdst = 1; } } else { gmtime_r(timer, ptm); /* * The date falls with the first three, or last three days * of the Epoch. It is possible the time_t representation * would overflow or underflow while compensating for * timezone and Daylight Savings Time. Therefore, make the * timezone and Daylight Savings Time adjustments directly * in the tm structure. The beginning of the Epoch is * 00:00:00, 01-01-70 (UCT) and the last representable second * in the Epoch is 03:14:07, 01-19-2038 (UCT). This will be * used in the calculations below. * * First, adjust for the timezone. */ if (_isindst(ptm)) ltime = (long) ptm->tm_sec - (_timezone + _dstbias); else ltime = (long) ptm->tm_sec - _timezone; ptm->tm_sec = (int) (ltime % 60); if (ptm->tm_sec < 0) { ptm->tm_sec += 60; ltime -= 60; } ltime = (long) ptm->tm_min + ltime / 60; ptm->tm_min = (int) (ltime % 60); if (ptm->tm_min < 0) { ptm->tm_min += 60; ltime -= 60; } ltime = (long) ptm->tm_hour + ltime / 60; ptm->tm_hour = (int) (ltime % 24); if (ptm->tm_hour < 0) { ptm->tm_hour += 24; ltime -= 24; } ltime /= 24; if (ltime > 0L) { /* * There is no possibility of overflowing the tm_mday * and tm_yday fields since the date can be no later * than January 19. */ ptm->tm_wday = (ptm->tm_wday + ltime) % 7; ptm->tm_mday += ltime; ptm->tm_yday += ltime; } else if (ltime < 0L) { /* * It is possible to underflow the tm_mday and tm_yday * fields. If this happens, then adjusted date must * lie in December 1969. */ ptm->tm_wday = (ptm->tm_wday + 7 + ltime) % 7; if ((ptm->tm_mday += ltime) <= 0) { ptm->tm_mday += 31; ptm->tm_yday = 364; ptm->tm_mon = 11; ptm->tm_year--; } else { ptm->tm_yday += ltime; } } } return 0; } /*! * \brief Convert a time value and correct for the local time zone. * * The localtime function converts a time stored as a time_t value and stores the * result in a structure of type ::tm. The long value \e timer represents the seconds * elapsed since midnight (00:00:00), January 1, 1970, UTC. This value is usually * obtained from the ::time function. * * ::gmtime, ::mktime, and \b localtime all use a single statically allocated ::tm structure * for the conversion. Each call to one of these routines destroys the result of the * previous call. * * \b localtime corrects for the local time zone if the user first sets the global * variable #_timezone. * * \param timer Pointer to stored time. * \return Return a pointer to the structure result. If the value in \e timer * represents a date before midnight, January 1, 1970, return \b NULL. * */ /* Note: This function is *not* thread safe, because it uses a static variable to store the calculated values. To be safe, you must surround the call to localtime _and_ the usage of the returned pointer with NutEnterCritical() and NutExitCritical()! Provided for compatibility to std c lib. */ tm *localtime(const time_t * timer) { if (localtime_r(timer, &_tb)) return NULL; else return &_tb; } /*@}*/