/* nstime.c * Routines for manipulating nstime_t structures * * Copyright (c) 2005 MX Telecom Ltd. * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * */ #include #include "nstime.h" /* this is #defined so that we can clearly see that we have the right number of zeros, rather than as a guard against the number of nanoseconds in a second changing ;) */ #define NS_PER_S 1000000000 /* set the given nstime_t to zero */ void nstime_set_zero(nstime_t *nstime) { nstime->secs = 0; nstime->nsecs = 0; } /* is the given nstime_t currently zero? */ gboolean nstime_is_zero(nstime_t *nstime) { if(nstime->secs == 0 && nstime->nsecs == 0) { return TRUE; } else { return FALSE; } } /* set the given nstime_t to (0,maxint) to mark it as "unset" * That way we can find the first frame even when a timestamp * is zero (fix for bug 1056) */ void nstime_set_unset(nstime_t *nstime) { nstime->secs = 0; nstime->nsecs = G_MAXINT; } /* is the given nstime_t currently (0,maxint)? */ gboolean nstime_is_unset(const nstime_t *nstime) { if(nstime->secs == 0 && nstime->nsecs == G_MAXINT) { return TRUE; } else { return FALSE; } } /** funcion: nstime_copy * * a = b */ void nstime_copy(nstime_t *a, const nstime_t *b) { a->secs = b->secs; a->nsecs = b->nsecs; } /* * function: nstime_delta * delta = b - a */ void nstime_delta(nstime_t *delta, const nstime_t *b, const nstime_t *a ) { if (b->secs == a->secs) { /* The seconds part of b is the same as the seconds part of a, so if the nanoseconds part of the first time is less than the nanoseconds part of a, b is before a. The nanoseconds part of the delta should just be the difference between the nanoseconds part of b and the nanoseconds part of a; don't adjust the seconds part of the delta, as it's OK if the nanoseconds part is negative, and an overflow can never result. */ delta->secs = 0; delta->nsecs = b->nsecs - a->nsecs; } else if (b->secs <= a->secs) { /* The seconds part of b is less than the seconds part of a, so b is before a. Both the "seconds" and "nanoseconds" value of the delta should have the same sign, so if the difference between the nanoseconds values would be *positive*, subtract 1,000,000,000 from it, and add one to the seconds value. */ delta->secs = b->secs - a->secs; delta->nsecs = b->nsecs - a->nsecs; if(delta->nsecs > 0) { delta->nsecs -= NS_PER_S; delta->secs ++; } } else { delta->secs = b->secs - a->secs; delta->nsecs = b->nsecs - a->nsecs; if(delta->nsecs < 0) { delta->nsecs += NS_PER_S; delta->secs --; } } } /* * function: nstime_sum * sum = a + b */ void nstime_sum(nstime_t *sum, const nstime_t *a, const nstime_t *b) { sum->secs = a->secs + b->secs; sum->nsecs = a->nsecs + b->nsecs; if(sum->nsecs>=NS_PER_S || (sum->nsecs>0 && sum->secs<0)){ sum->nsecs-=NS_PER_S; sum->secs++; } else if(sum->nsecs<=-NS_PER_S || (sum->nsecs<0 && sum->secs>0)) { sum->nsecs+=NS_PER_S; sum->secs--; } } /* * function: nstime_cmp * * a > b : > 0 * a = b : 0 * a < b : < 0 */ int nstime_cmp (const nstime_t *a, const nstime_t *b ) { if (G_UNLIKELY(nstime_is_unset(a))) { if (G_UNLIKELY(nstime_is_unset(b))) { return 0; /* "no time stamp" is "equal" to "no time stamp" */ } else { return -1; /* and is less than all time stamps */ } } else { if (G_UNLIKELY(nstime_is_unset(b))) { return 1; } } if (a->secs == b->secs) { return a->nsecs - b->nsecs; } else { return (int) (a->secs - b->secs); } } /* * function: nstime_to_msec * converts nstime to double, time base is milli seconds */ double nstime_to_msec(const nstime_t *nstime) { return ((double)nstime->secs*1000 + (double)nstime->nsecs/1000000); } /* * function: nstime_to_sec * converts nstime to double, time base is seconds */ double nstime_to_sec(const nstime_t *nstime) { return ((double)nstime->secs + (double)nstime->nsecs/NS_PER_S); } /* * This code is based on the Samba code: * * Unix SMB/Netbios implementation. * Version 1.9. * time handling functions * Copyright (C) Andrew Tridgell 1992-1998 */ /* * Number of seconds between the UN*X epoch (January 1, 1970, 00:00:00 GMT) * and the Windows NT epoch (January 1, 1601 in the proleptic Gregorian * calendar, 00:00:00 "GMT") * * This is * * 369*365.25*24*60*60-(3*24*60*60+6*60*60) * * 1970-1601 is 369; 365.25 is the average length of a year in days, * including leap years. * * 3 days are subtracted because 1700, 1800, and 1900 were not leap * years, as, while they're all evenly divisible by 4, they're also * evently divisible by 100, but not evently divisible by 400, so * we need to compensate for using the average length of a year in * days, which assumes a leap year every 4 years, *including* every * 100 years. * * I'm not sure what the extra 6 hours are that are being subtracted. */ #define TIME_FIXUP_CONSTANT G_GUINT64_CONSTANT(11644473600) #ifndef TIME_T_MIN #define TIME_T_MIN ((time_t) ((time_t)0 < (time_t) -1 ? (time_t) 0 \ : (time_t) (~0ULL << (sizeof (time_t) * CHAR_BIT - 1)))) #endif #ifndef TIME_T_MAX #define TIME_T_MAX ((time_t) (~ (time_t) 0 - TIME_T_MIN)) #endif static gboolean common_filetime_to_nstime(nstime_t *nstime, guint64 ftsecs, int nsecs) { gint64 secs; /* * Shift the seconds from the Windows epoch to the UN*X epoch. * ftsecs's value should fit in a 64-bit signed variable, as * ftsecs is derived from a 64-bit fractions-of-a-second value, * and is far from the maximum 64-bit signed value, and * TIME_FIXUP_CONSTANT is also far from the maximum 64-bit * signed value, so the difference between them should also * fit in a 64-bit signed value. */ secs = (gint64)ftsecs - TIME_FIXUP_CONSTANT; if (!(TIME_T_MIN <= secs && secs <= TIME_T_MAX)) { /* The result won't fit in a time_t */ return FALSE; } /* * Get the time as seconds and nanoseconds. */ nstime->secs = (time_t) secs; nstime->nsecs = nsecs; return TRUE; } /* * function: filetime_to_nstime * converts a Windows FILETIME value to an nstime_t * returns TRUE if the conversion succeeds, FALSE if it doesn't * (for example, with a 32-bit time_t, the time overflows or * underflows time_t) */ gboolean filetime_to_nstime(nstime_t *nstime, guint64 filetime) { guint64 ftsecs; int nsecs; /* * Split into seconds and tenths of microseconds, and * then convert tenths of microseconds to nanoseconds. */ ftsecs = filetime / 10000000; nsecs = (int)((filetime % 10000000)*100); return common_filetime_to_nstime(nstime, ftsecs, nsecs); } /* * function: nsfiletime_to_nstime * converts a Windows FILETIME-like value, but given in nanoseconds * rather than 10ths of microseconds, to an nstime_t * returns TRUE if the conversion succeeds, FALSE if it doesn't * (for example, with a 32-bit time_t, the time overflows or * underflows time_t) */ gboolean nsfiletime_to_nstime(nstime_t *nstime, guint64 nsfiletime) { guint64 ftsecs; int nsecs; /* Split into seconds and nanoseconds. */ ftsecs = nsfiletime / NS_PER_S; nsecs = (int)(nsfiletime % NS_PER_S); return common_filetime_to_nstime(nstime, ftsecs, nsecs); } /* * Editor modelines * * Local Variables: * c-basic-offset: 4 * tab-width: 8 * indent-tabs-mode: nil * End: * * ex: set shiftwidth=4 tabstop=8 expandtab: * :indentSize=4:tabSize=8:noTabs=true: */