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| author | Guy Harris <guy@alum.mit.edu> | 2020-01-21 14:26:38 -0800 |
|---|---|---|
| committer | Guy Harris <guy@alum.mit.edu> | 2020-01-21 23:37:05 +0000 |
| commit | a152e041fa893ba672dcb1337c596ec15fdb0c0d (patch) | |
| tree | 17debde7ec0104d70d12e67bb4e5d8764ef076d1 /wsutil/epochs.h | |
| parent | d44c5e45cbb5e9ece96cab6a62793dd24ec52b7d (diff) | |
Put various epoch time deltas into wsutil/epochs.h.
There are some deltas between the UN*X epoch and other epochs that are
used in a number of places; put them into a header.
Change-Id: Ia2d9d69b9d91352d730d97d9e4897518635b4861
Reviewed-on: https://code.wireshark.org/review/35895
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <guy@alum.mit.edu>
Diffstat (limited to 'wsutil/epochs.h')
| -rw-r--r-- | wsutil/epochs.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/wsutil/epochs.h b/wsutil/epochs.h new file mode 100644 index 0000000000..c6f28cea6a --- /dev/null +++ b/wsutil/epochs.h @@ -0,0 +1,57 @@ +/* epochs.h + * Definitions of epoch values for various absolute time types. + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 2006 Gerald Combs + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#ifndef __EPOCHS_H__ +#define __EPOCHS_H__ + +#include <glib.h> + +/* + * Deltas between the epochs for various non-UN*X time stamp formats and + * the January 1, 1970, 00:00:00 (proleptic?) UTC epoch for the UN*X time + * stamp format. + */ + +/* + * 1900-01-01 00:00:00 (proleptic?) UTC. + * Used by a number of time formats. + */ +#define EPOCH_DELTA_1900_01_01_00_00_00_UTC 2208988800U + +/* + * 1904-01-01 00:00:00 (proleptic?) UTC. + * Used in the classic Mac OS, and by formats, such as MPEG-4 Part 14 (MP4), + * which is based on Apple's QuickTime format. + */ +#define EPOCH_DELTA_1904_01_01_00_00_00_UTC 2082844800U + +/* + * 1601-01-01 (proleptic Gregorian) 00:00:00 (proleptic?) UTC. + * The Windows NT epoch, used in a number of places. + * + * 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 EPOCH_DELTA_1601_01_01_00_00_00_UTC G_GUINT64_CONSTANT(11644473600) + +#endif /* __EPOCHS_H__ */ |