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+/*
+ * Copyright (c) 1987, 1989 Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Arthur David Olson of the National Cancer Institute.
+ *
+ * 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. */
+
+/*static char *sccsid = "from: @(#)ctime.c 5.26 (Berkeley) 2/23/91";*/
+
+/*
+ * This implementation of mktime is lifted straight from the NetBSD (BSD 4.4)
+ * version. I modified it slightly to divorce it from the internals of the
+ * ctime library. Thus this version can't use details of the internal
+ * timezone state file to figure out strange unnormalized struct tm values,
+ * as might result from someone doing date math on the tm struct then passing
+ * it to mktime.
+ *
+ * It just does as well as it can at normalizing the tm input, then does a
+ * binary search of the time space using the system's localtime() function.
+ *
+ * The original binary search was defective in that it didn't consider the
+ * setting of tm_isdst when comparing tm values, causing the search to be
+ * flubbed for times near the dst/standard time changeover. The original
+ * code seems to make up for this by grubbing through the timezone info
+ * whenever the binary search barfed. Since I don't have that luxury in
+ * portable code, I have to take care of tm_isdst in the comparison routine.
+ * This requires knowing how many minutes offset dst is from standard time.
+ *
+ * So, if you live somewhere in the world where dst is not 60 minutes offset,
+ * and your vendor doesn't supply mktime(), you'll have to edit this variable
+ * by hand. Sorry about that.
+ */
+
+#include "db_config.h"
+
+#include "db_int.h"
+
+#undef DSTMINUTES
+#define DSTMINUTES 60
+
+#undef FALSE
+#undef TRUE
+#define FALSE 0
+#define TRUE 1
+
+/*
+** Adapted from code provided by Robert Elz, who writes:
+** The "best" way to do mktime I think is based on an idea of Bob
+** Kridle's (so its said...) from a long time ago. (mtxinu!kridle now).
+** It does a binary search of the time_t space. Since time_t's are
+** just 32 bits, its a max of 32 iterations (even at 64 bits it
+** would still be very reasonable).
+*/
+
+#undef WRONG
+#define WRONG (-1)
+
+const unsigned int mon_lengths[2][MONSPERYEAR] = {
+ { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
+ { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
+};
+const unsigned int year_lengths[2] = {
+ DAYSPERNYEAR, DAYSPERLYEAR
+};
+
+static void
+normalize(tensptr, unitsptr, base)
+ int base, *tensptr, *unitsptr;
+{
+ if (*unitsptr >= base) {
+ *tensptr += *unitsptr / base;
+ *unitsptr %= base;
+ } else if (*unitsptr < 0) {
+ --*tensptr;
+ *unitsptr += base;
+ if (*unitsptr < 0) {
+ *tensptr -= 1 + (-*unitsptr) / base;
+ *unitsptr = base - (-*unitsptr) % base;
+ }
+ }
+}
+
+static struct tm *
+mkdst(tmp)
+ struct tm * tmp;
+{
+ /* jds */
+ static struct tm tmbuf;
+
+ tmbuf = *tmp;
+ tmbuf.tm_isdst = 1;
+ tmbuf.tm_min += DSTMINUTES;
+ normalize(&tmbuf.tm_hour, &tmbuf.tm_min, MINSPERHOUR);
+ return &tmbuf;
+}
+
+static int
+tmcomp(atmp, btmp)
+ register struct tm *atmp, *btmp;
+{
+ register int result;
+
+ /* compare down to the same day */
+ if ((result = (atmp->tm_year - btmp->tm_year)) == 0 &&
+ (result = (atmp->tm_mon - btmp->tm_mon)) == 0)
+ result = (atmp->tm_mday - btmp->tm_mday);
+
+ if (result != 0)
+ return result;
+
+ /* get rid of one-sided dst bias */
+ if (atmp->tm_isdst == 1 && !btmp->tm_isdst)
+ btmp = mkdst(btmp);
+ else if (btmp->tm_isdst == 1 && !atmp->tm_isdst)
+ atmp = mkdst(atmp);
+
+ /* compare the rest of the way */
+ if ((result = (atmp->tm_hour - btmp->tm_hour)) == 0 &&
+ (result = (atmp->tm_min - btmp->tm_min)) == 0)
+ result = atmp->tm_sec - btmp->tm_sec;
+
+ return result;
+}
+
+static time_t
+time2(tmp, okayp, usezn)
+ struct tm *tmp;
+ int *okayp, usezn;
+{
+ register int bits, dir, i, saved_seconds;
+ time_t t;
+ struct tm yourtm, mytm;
+
+ *okayp = FALSE;
+ yourtm = *tmp;
+ if (yourtm.tm_sec >= SECSPERMIN + 2 || yourtm.tm_sec < 0)
+ normalize(&yourtm.tm_min, &yourtm.tm_sec, SECSPERMIN);
+ normalize(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR);
+ normalize(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY);
+ normalize(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR);
+ while (yourtm.tm_mday <= 0) {
+ --yourtm.tm_year;
+ yourtm.tm_mday +=
+ year_lengths[isleap(yourtm.tm_year + TM_YEAR_BASE)];
+ }
+ for ( ; ; ) {
+ i = mon_lengths[isleap(yourtm.tm_year +
+ TM_YEAR_BASE)][yourtm.tm_mon];
+ if (yourtm.tm_mday <= i)
+ break;
+ yourtm.tm_mday -= i;
+ if (++yourtm.tm_mon >= MONSPERYEAR) {
+ yourtm.tm_mon = 0;
+ ++yourtm.tm_year;
+ }
+ }
+ saved_seconds = yourtm.tm_sec;
+ yourtm.tm_sec = 0;
+ /*
+ ** Calculate the number of magnitude bits in a time_t
+ ** (this works regardless of whether time_t is
+ ** signed or unsigned, though lint complains if unsigned).
+ */
+ for (bits = 0, t = 1; t > 0; ++bits, t <<= 1)
+ ;
+ /*
+ ** If time_t is signed, then 0 is the median value,
+ ** if time_t is unsigned, then 1 << bits is median.
+ */
+ t = (t < 0) ? 0 : ((time_t) 1 << bits);
+ for ( ; ; ) {
+ if (usezn)
+ mytm = *localtime(&t);
+ else
+ mytm = *gmtime(&t);
+ dir = tmcomp(&mytm, &yourtm);
+ if (dir != 0) {
+ if (bits-- < 0)
+ return WRONG;
+ if (bits < 0)
+ --t;
+ else if (dir > 0)
+ t -= (time_t) 1 << bits;
+ else t += (time_t) 1 << bits;
+ continue;
+ }
+ if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst)
+ break;
+
+ return WRONG;
+ }
+ t += saved_seconds;
+ if (usezn)
+ *tmp = *localtime(&t);
+ else
+ *tmp = *gmtime(&t);
+ *okayp = TRUE;
+ return t;
+}
+
+static time_t
+time1(tmp)
+ struct tm * tmp;
+{
+ register time_t t;
+ int okay;
+
+ if (tmp->tm_isdst > 1)
+ tmp->tm_isdst = 1;
+ t = time2(tmp, &okay, 1);
+ if (okay || tmp->tm_isdst < 0)
+ return t;
+
+ return WRONG;
+}
+
+/*
+ * mktime --
+ *
+ * PUBLIC: #ifdef DB_WINCE
+ * PUBLIC: time_t __ce_mktime __P((struct tm *));
+ * PUBLIC: #endif
+ */
+time_t
+__ce_mktime(tmp)
+ struct tm * tmp;
+{
+ return time1(tmp);
+}