Timestamp handling

Timestamp handling — Convenience functions for dealing with timestamps and dates

Functions

Types and Values

Includes

#include <zeitgeist.h>

Description

A suite of convenience functions for dealing with timestamps and dates.

Zeitgeist timestamps are represented as gint64s with the number of milliseconds since the Unix Epoch.

Functions

zeitgeist_timestamp_for_now ()

gint64
zeitgeist_timestamp_for_now (void);

Get the timestamp for the current system time

Returns

The timestamp for the current system time. Ie. the number of milliseconds since the Unix Epoch


zeitgeist_timestamp_from_date ()

gint64
zeitgeist_timestamp_from_date (GDate *date);

Convert a GDate to a Zeitgeist timestamp.

Parameters

date

A GDate to convert

 

Returns

date as a timestamp in milliseconds since the Epoch. The timestamp is guaranteed to be rounded off to the midnight of the given date.


zeitgeist_timestamp_from_dmy ()

gint64
zeitgeist_timestamp_from_dmy (GDateDay day,
                              GDateMonth month,
                              GDateYear year);

Convert a day, month, year tuple into a Zeitgeist timestamp

Parameters

day

The day of the month represented as a GDateDay

 

month

The month of the year represented as a GDateMonth

 

year

The year represented as a GDateYear

 

Returns

Input data as a timestamp in milliseconds since the Epoch or -1 in case the provided data does not constitute a valid date. If the date is valid the returned timestamp is guaranteed to be rounded off to the midnight of the given date


zeitgeist_timestamp_from_iso8601 ()

gint64
zeitgeist_timestamp_from_iso8601 (const gchar *datetime);

Parse a timestamp from a ISO8601 encoded string.

Parameters

datetime

A string containing an iso8601 conforming datetime specification

 

Returns

The timestamp represented by datetime , or -1 on failure to parse datetime


zeitgeist_timestamp_from_timeval ()

gint64
zeitgeist_timestamp_from_timeval (GTimeVal *tv);

Parameters

tv

A GTimeVal instance

 

Returns

A gint64 with the total number of milliseconds since the Unix Epoch


zeitgeist_timestamp_next_midnight ()

gint64
zeitgeist_timestamp_next_midnight (gint64 timestamp);

Calculate the timestamp for the next midnight after timestamp

Parameters

timestamp

The Zeitgeist timestamp to find the next midnight for

 

Returns

Returns the timestamp for the first midnight after timestamp . If timestamp is already midnight (down to the millisecond) this method will return the value for the next midnight. In other words you can call this method recursively in order to iterate, forwards in time, over midnights.


zeitgeist_timestamp_prev_midnight ()

gint64
zeitgeist_timestamp_prev_midnight (gint64 timestamp);

Calculate the timestamp for the midnight just before timestamp

Parameters

timestamp

The Zeitgeist timestamp to find the previous midnight for

 

Returns

Returns the timestamp for the first midnight just before timestamp . If timestamp is already midnight (down to the millisecond) this method will return the value for the midnight before. In other words you can call this method recursively in order to iterate, backwards in time, over midnights.


zeitgeist_timestamp_to_date ()

void
zeitgeist_timestamp_to_date (gint64 timestamp,
                             GDate *date);

Write a timestamp to a GDate structure

Parameters

timestamp

The Zeitgeist timestamp to convert to a GDate

 

date

The place to store the result in. Must be non-NULL

 

zeitgeist_timestamp_to_iso8601 ()

gchar *
zeitgeist_timestamp_to_iso8601 (gint64 timestamp);

Convert a timestamp to a human readable ISO8601 format

Parameters

timestamp

A Zeitgeist timestamp in ms since the Epoch

 

Returns

A newly allocated string containing the ISO8601 format of timestamp . Free with g_free().


zeitgeist_timestamp_to_timeval ()

void
zeitgeist_timestamp_to_timeval (gint64 timestamp,
                                GTimeVal *tv);

Write a Zeitgeist timestamp to a GTimeVal instance. Note that Zeitgeist uses only a millisecond resolution for where GTimeVal uses a microsecond resolution, meaning that the lower three digits of tv.tv_usec will be 0.

Parameters

timestamp

A gint64 with a number of milliseconds since the Unix Epoch

 

tv

A GTimeVal instance to store the result in

 

Types and Values

ZEITGEIST_TIMESTAMP_SECOND

#define ZEITGEIST_TIMESTAMP_SECOND G_GINT64_CONSTANT (1000)

A second represented as a Zeitgeist timestamp (ie. 1000ms)


ZEITGEIST_TIMESTAMP_MINUTE

#define ZEITGEIST_TIMESTAMP_MINUTE G_GINT64_CONSTANT (60000)

A minute represented as a Zeitgeist timestamp (ie. 60000ms)


ZEITGEIST_TIMESTAMP_HOUR

#define ZEITGEIST_TIMESTAMP_HOUR G_GINT64_CONSTANT (3600000)

An hour represented as a Zeitgeist timestamp (ie. 3600000ms)


ZEITGEIST_TIMESTAMP_DAY

#define ZEITGEIST_TIMESTAMP_DAY G_GINT64_CONSTANT (86400000)

A day represented as a Zeitgeist timestamp (ie. 86400000ms)


ZEITGEIST_TIMESTAMP_WEEK

#define ZEITGEIST_TIMESTAMP_WEEK G_GINT64_CONSTANT (604800000)

A week represented as a Zeitgeist timestamp (ie. 604800000ms)


ZEITGEIST_TIMESTAMP_YEAR

#define ZEITGEIST_TIMESTAMP_YEAR G_GINT64_CONSTANT (31556952000)

A year represented as a Zeitgeist timestamp (ie. 31556952000ms). Be warned that a year is not 365 days, but in fact 365.2425 days to account for leap years.