codec.c File Reference

D-Bus encoding/decoding utilities. More...

#include <string.h>
#include <stdio.h>
#include "codec.h"
#include "logging.h"

Functions
int	decode_int (DBusMessageIter *iter, int *pval)
int	decode_tm (DBusMessageIter *iter, struct tm *tm)
int	decode_ctm (DBusMessageIter *iter, struct tm *tm)

---

Detailed Description

Utilites for encoding/decoding dbus messages using message iterators. Useful only because libdbus does not expose some internal functions via the public API.

Copyright (C) 2008 Nokia. All rights reserved.

Author:

Simo Piiroinen <simo.piiroinen@nokia.com>

Raimo Vuonnala <raimo.vuonnala@nokia.com>

---

Function Documentation

int decode_int	(	DBusMessageIter *	iter,
		int *	pval
	)

Decode iteratively integer.

Parameters:

	iter	DBusMessageIter
	pval	Pointer to int to store the decoded integer

Returns:

-1 if error, 0 if success

int decode_tm	(	DBusMessageIter *	iter,
		struct tm *	tm
	)

Decode struct tm

Parameters:

	iter	DBusMessageIter
	tm	Pointer to struct tm to store the decoded time

Returns:

-1 if error, 0 if success

int decode_ctm	(	DBusMessageIter *	iter,
		struct tm *	tm
	)

Decode NET_TIME_IND to struct tm

The information may include the current date (day-month-year) and time (hour-minute-second) in UTC (Coordinated Universal Time), which is in practice same as GMT (Greenwich Mean Time).

Daylight Saving Time

• NET_DST_INFO_NOT_AVAIL 0x64
• NET_DST_1_HOUR 0x01
• NET_DST_2_HOURS 0x02
• NET_DST_0_HOUR 0x00

Example 1:
if the time is 12:00:00 and time zone is GMT+2 hours and daylight saving time information is NET_DST_1_HOUR then the local time is 12:00:00 + 2 hours = 14:00:00. The Universal time is 12:00:00, the daylight saving is in use, so the normal time in that area would be 13:00:00.

Example 2:
if universal time information is missing, but time zone information indicates GMT - 10 hours, then the local time is 02:00:00 when universal time is 12:00:00.

Example 3:
if universal time information is missing and time zone information is missing, but daylight saving time information indicate NET_DST_1_HOUR then it can be known that daylight saving of 1 hour is used currently in the area and the current local time is +1 hours from the normal local time. However, if time zone is not known it is not possible to determine the local time. (The time zone might be known by some other means.)

See:

• http://www.timeanddate.com/worldclock/
• http://www.timeanddate.com/library/abbreviations/timezones/na/pst.html
• http://www.timeanddate.com/library/abbreviations/timezones/eu/eet.html

• UTC time is 22:00 1st May 2008
• What is the YMDhms in Finland? 2. May 2008, 00:00:00

• What is the value of Timezone in Finland? UTC+2 hours EET
• What is the YMDhms in California? San Francisco (U.S.A. - California) 1. May 2008, 14:00:00

• What is the value of Timezone in California ? UTC-8 hours PST
  

See spec: https://svni1.isource-nokia.nokia.com/isource/svnroot/ngsp-swd/ngsp-alpha/trunk/casw/telephony-adaptation/libcsnet/net_dbus_interface.txt

Parameters:

	iter	DBusMessageIter
	tm	Pointer to struct tm to store the decoded time. tm->tm_yday is the UTC offset in secs.

Returns:

-1 if error, 0 if success

Referenced by handle_csd_net_time_change().