/* $NetBSD: clock_subr.c,v 1.27 2016/08/15 15:51:39 jakllsch Exp $ */ /* * Copyright (c) 1988 University of Utah. * Copyright (c) 1982, 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department. * * 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 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. * * from: Utah $Hdr: clock.c 1.18 91/01/21$ * * @(#)clock.c 8.2 (Berkeley) 1/12/94 */ /* * Generic routines to convert between a POSIX date * (seconds since 1/1/1970) and yr/mo/day/hr/min/sec * Derived from arch/hp300/hp300/clock.c */ #if HAVE_NBTOOL_CONFIG_H #include "nbtool_config.h" #endif /* HAVE_NBTOOL_CONFIG_H */ #ifdef _KERNEL #include <sys/cdefs.h> __KERNEL_RCSID(0, "$NetBSD: clock_subr.c,v 1.27 2016/08/15 15:51:39 jakllsch Exp $"); #include <sys/param.h> #include <sys/systm.h> #include <sys/errno.h> #else /* ! _KERNEL */ #include <string.h> #include <time.h> #include <errno.h> #endif /* ! _KERNEL */ #include "../sys/clock.h" #include <dev/clock_subr.h> #define FEBRUARY 2 /* for easier alignment: * time from the epoch to 2001 (there were 8 leap years): */ #define DAYSTO2001 (365*31+8) /* 4 year intervals include 1 leap year */ #define DAYS4YEARS (365*4+1) /* 100 year intervals include 24 leap years */ #define DAYS100YEARS (365*100+24) /* 400 year intervals include 97 leap years */ #define DAYS400YEARS (365*400+97) time_t clock_ymdhms_to_secs(struct clock_ymdhms *dt) { uint64_t secs, i, year, days; year = dt->dt_year; /* * Compute days since start of time * First from years, then from months. */ if (year < POSIX_BASE_YEAR) return -1; days = 0; if (is_leap_year(year) && dt->dt_mon > FEBRUARY) days++; if (year < 2001) { /* simple way for early years */ for (i = POSIX_BASE_YEAR; i < year; i++) days += days_per_year(i); } else { /* years are properly aligned */ days += DAYSTO2001; year -= 2001; i = year / 400; days += i * DAYS400YEARS; year -= i * 400; i = year / 100; days += i * DAYS100YEARS; year -= i * 100; i = year / 4; days += i * DAYS4YEARS; year -= i * 4; for (i = dt->dt_year-year; i < dt->dt_year; i++) days += days_per_year(i); } /* Months */ for (i = 1; i < dt->dt_mon; i++) days += days_in_month(i); days += (dt->dt_day - 1); /* Add hours, minutes, seconds. */ secs = (((uint64_t)days * 24 + dt->dt_hour) * 60 + dt->dt_min) * 60 + dt->dt_sec; if ((time_t)secs < 0 || secs > __type_max(time_t)) return -1; return secs; } int clock_secs_to_ymdhms(time_t secs, struct clock_ymdhms *dt) { int leap; uint64_t i; time_t days; time_t rsec; /* remainder seconds */ if (secs < 0) return EINVAL; days = secs / SECS_PER_DAY; rsec = secs % SECS_PER_DAY; /* Day of week (Note: 1/1/1970 was a Thursday) */ dt->dt_wday = (days + 4) % 7; if (days >= DAYSTO2001) { days -= DAYSTO2001; dt->dt_year = 2001; i = days / DAYS400YEARS; days -= i*DAYS400YEARS; dt->dt_year += i*400; i = days / DAYS100YEARS; days -= i*DAYS100YEARS; dt->dt_year += i*100; i = days / DAYS4YEARS; days -= i*DAYS4YEARS; dt->dt_year += i*4; for (i = dt->dt_year; days >= days_per_year(i); i++) days -= days_per_year(i); dt->dt_year = i; } else { /* Subtract out whole years, counting them in i. */ for (i = POSIX_BASE_YEAR; days >= days_per_year(i); i++) days -= days_per_year(i); dt->dt_year = i; } /* Subtract out whole months, counting them in i. */ for (leap = 0, i = 1; days >= days_in_month(i)+leap; i++) { days -= days_in_month(i)+leap; if (i == 1 && is_leap_year(dt->dt_year)) leap = 1; else leap = 0; } dt->dt_mon = i; /* Days are what is left over (+1) from all that. */ dt->dt_day = days + 1; /* Hours, minutes, seconds are easy */ dt->dt_hour = rsec / SECS_PER_HOUR; rsec = rsec % SECS_PER_HOUR; dt->dt_min = rsec / SECS_PER_MINUTE; rsec = rsec % SECS_PER_MINUTE; dt->dt_sec = rsec; return 0; }
