time_util.h File Reference

#include <wireshark.h>
#include <time.h>

Go to the source code of this file.

Functions
WS_DLL_PUBLIC time_t	mktime_utc (struct tm *tm)
	Converts a UTC-based broken-down time to a timestamp.
WS_DLL_PUBLIC bool	tm_is_valid (struct tm *tm)
	Validates the fields of a broken-down time structure.
WS_DLL_PUBLIC void	get_resource_usage (double *user_time, double *sys_time)
	Retrieves the current process CPU usage.
WS_DLL_PUBLIC void	log_resource_usage (bool reset_delta, const char *format,...)
	Logs the process CPU usage along with a formatted message.
WS_DLL_PUBLIC uint64_t	create_timestamp (void)
	Fetches the number of microseconds since the Unix epoch.
WS_DLL_PUBLIC void	ws_tzset (void)
	Initializes or updates timezone settings.
WS_DLL_PUBLIC struct timespec *	ws_clock_get_realtime (struct timespec *ts)
	Retrieves the current real-time clock value.
WS_DLL_PUBLIC struct tm *	ws_localtime_r (const time_t *timep, struct tm *result)
	Converts a time value to local time.
WS_DLL_PUBLIC struct tm *	ws_gmtime_r (const time_t *timep, struct tm *result)
	Converts a time value to UTC (GMT).

Detailed Description

Wireshark - Network traffic analyzer By Gerald Combs geral.nosp@m.d@wi.nosp@m.resha.nosp@m.rk.o.nosp@m.rg Copyright 1998 Gerald Combs

SPDX-License-Identifier: GPL-2.0-or-later

Function Documentation

create_timestamp()

WS_DLL_PUBLIC uint64_t create_timestamp

(

void

)

Fetches the number of microseconds since the Unix epoch.

Returns the current time as a 64-bit unsigned integer representing microseconds since midnight (00:00:00), January 1, 1970 (UTC).

Returns

The current timestamp in microseconds since the epoch.

get_resource_usage()

WS_DLL_PUBLIC void get_resource_usage	(	double *	user_time,
		double *	sys_time
	)

Retrieves the current process CPU usage.

Fetches the amount of time the process has spent in user and system (kernel) mode, and stores the values in seconds.

Parameters

user_time	Pointer to receive user-mode CPU time in seconds.
sys_time	Pointer to receive system-mode CPU time in seconds.

log_resource_usage()

WS_DLL_PUBLIC void log_resource_usage	(	bool	reset_delta,
		const char *	format,
			...
	)

Logs the process CPU usage along with a formatted message.

Prints the current user and system CPU times, and optionally resets the delta used for tracking elapsed time between measurements.

Parameters

reset_delta	If true, resets the delta timer after logging.
format	Printf-style format string for the log message.
...	Arguments for the format string.

mktime_utc()

WS_DLL_PUBLIC time_t mktime_utc

(

struct tm *

tm

)

Converts a UTC-based broken-down time to a timestamp.

Converts a struct tm representing a UTC time into a time_t value. This is similar to mktime() but assumes the input is in UTC rather than local time.

Parameters

tm	Pointer to a struct tm representing UTC time.

Returns

The corresponding time_t value.

tm_is_valid()

WS_DLL_PUBLIC bool tm_is_valid

(

struct tm *

tm

)

Validates the fields of a broken-down time structure.

Checks whether the values in a struct tm are within valid ranges. Only tm_year, tm_mon, tm_mday, tm_hour, tm_min, and tm_sec are validated. Fields tm_wday, tm_yday, and tm_isdst are ignored.

Parameters

tm	Pointer to the struct tm to validate.

Returns

true if the structure contains valid values, false otherwise.

ws_clock_get_realtime()

WS_DLL_PUBLIC struct timespec * ws_clock_get_realtime

(

struct timespec *

ts

)

Retrieves the current real-time clock value.

Fills the provided timespec structure with the current time from the system clock.

Parameters

ts	Pointer to a struct timespec to receive the current time.

Returns

Pointer to the same ts structure, or NULL on failure.

ws_gmtime_r()

WS_DLL_PUBLIC struct tm * ws_gmtime_r	(	const time_t *	timep,
		struct tm *	result
	)

Converts a time value to UTC (GMT).

Thread-safe version of gmtime(). Converts a time_t value to a struct tm representing UTC time. The result is stored in the caller-provided buffer.

Parameters

timep	Pointer to the time value to convert.
result	Pointer to a struct tm to receive the result.

Returns

Pointer to result, or NULL on failure.

ws_localtime_r()

WS_DLL_PUBLIC struct tm * ws_localtime_r	(	const time_t *	timep,
		struct tm *	result
	)

Converts a time value to local time.

Thread-safe version of localtime(). Converts a time_t value to a struct tm representing local time. The result is stored in the caller-provided buffer.

Parameters

timep	Pointer to the time value to convert.
result	Pointer to a struct tm to receive the result.

Returns

Pointer to result, or NULL on failure.

ws_tzset()

WS_DLL_PUBLIC void ws_tzset

(

void

)

Initializes or updates timezone settings.

Calls the system-specific timezone setup routine (e.g., tzset()) to ensure local time conversions reflect the current environment.