libdar::datetime Class Reference

stores time information More...

#include <datetime.hpp>

Collaboration diagram for libdar::datetime:

Public Types
enum	time_unit { tu_nanosecond , tu_microsecond , tu_second }

Public Member Functions
	datetime (const infinint &value=0)
	constructor based on the number of second ellasped since the end of 1969 More...
	datetime (time_t second, time_t subsec, time_unit unit)
	general constructor More...
	datetime (generic_file &x, archive_version ver)
	constructor reading data dump() into a generic_file
	datetime (const datetime &ref)=default
	datetime (datetime &&ref) noexcept=default
datetime &	operator= (const datetime &ref)=default
datetime &	operator= (datetime &&ref) noexcept=default
bool	operator< (const datetime &ref) const
bool	operator== (const datetime &ref) const
bool	operator!= (const datetime &ref) const
bool	operator>= (const datetime &ref) const
bool	operator> (const datetime &ref) const
bool	operator<= (const datetime &ref) const
void	operator-= (const datetime &ref)
void	operator+= (const datetime &ref)
datetime	operator- (const datetime &ref) const
datetime	operator+ (const datetime &ref) const
bool	loose_equal (const datetime &ref) const
	equivalent to operator == but if compared object use different time unit, do the comparison rounding up the values to the largest unit
datetime	loose_diff (const datetime &ref) const
	at the difference of operator - provides the difference using the less precise unit used between the two elements
infinint	get_second_value () const
	return the integer number of second More...
infinint	get_subsecond_value (time_unit unit) const
	return the subsecond time fraction expressed in the given time unit
time_unit	get_unit () const
	returns the time unit used internally to store the subsecond time fraction More...
bool	get_value (time_t &second, time_t &subsecond, time_unit unit) const
	return a time as time_t arguments More...
void	dump (generic_file &x) const
	write down this to file
void	read (generic_file &f, archive_version ver)
	read this from file
bool	is_null () const
	return true if the datetime is exactly January 1st, 1970, 0 h 0 mn 0 s More...
bool	is_integer_second () const
	return true if the datetime is an integer number of second (subsecond part is zero) More...
infinint	get_storage_size () const
	return the storage it would require to dump this object
void	nullify ()
	set to null (zero) More...

Static Public Member Functions
static std::string	unit_symbol (time_unit tu)
	return the SI symbol of the time unit (s, ms, us (should be mu greek letter), ns)

Private Member Functions
void	reduce_to_largest_unit () const
	reduce the value to the largest unit possible
void	get_value (infinint &sec, infinint &sub, time_unit unit) const
void	build (const infinint &sec, const infinint &sub, time_unit unit)

Static Private Member Functions
static time_unit	min (time_unit a, time_unit b)
static time_unit	max (time_unit a, time_unit b)
static char	time_unit_to_char (time_unit a)
static time_unit	char_to_time_unit (const char a)
static const infinint &	get_scaling_factor (time_unit source, time_unit dest)
	return the factor between two units More...

Private Attributes
infinint	val
	the date expressed in the "uni" time unit More...
time_unit	uni
	the time unit used to store the subsecond fraction of the timestamp. More...

Detailed Description

stores time information

Definition at line 58 of file datetime.hpp.

Member Enumeration Documentation

time_unit

enum libdar::datetime::time_unit

Definition at line 63 of file datetime.hpp.

Constructor & Destructor Documentation

datetime() [1/2]

libdar::datetime::datetime ( const infinint &  value = 0 )

inline

constructor based on the number of second ellasped since the end of 1969

Definition at line 66 of file datetime.hpp.

References uni, and val.

datetime() [2/2]

libdar::datetime::datetime	(	time_t	second,
		time_t	subsec,
		time_unit	unit
	)

general constructor

Parameters

[in]	second	the number of second since the dawn of computer time (1970)
[in]	subsec	the fraction of the time below 1 second expressed in the time unit given as next argument
[in]	unit	the time unit in which is expressed the previous argument

Member Function Documentation

get_scaling_factor()

static const infinint & libdar::datetime::get_scaling_factor ( time_unit  source, time_unit  dest  )

staticprivate

return the factor between two units

Note

"source" must be larger than "dest" (source >= dest), else an exception is thrown

Returns

the factor f, which makes the following to be true: source = f*dest

get_second_value()

infinint libdar::datetime::get_second_value ( ) const

inline

return the integer number of second

Definition at line 107 of file datetime.hpp.

References get_value(), and uni.

get_unit()

time_unit libdar::datetime::get_unit ( ) const

inline

returns the time unit used internally to store the subsecond time fraction

Definition at line 113 of file datetime.hpp.

References uni.

get_value()

bool libdar::datetime::get_value	(	time_t &	second,
		time_t &	subsecond,
		time_unit	unit
	)		const

return a time as time_t arguments

Parameters

[out]	second	the time value in second
[out]	subsecond	is the remaining time fraction as expressed in the unit given as next argument
[in]	unit	the unit of the subsecond fraction of the timestamp

Returns

true upon success, false if the value cannot be represented by system types (overflow)

Referenced by libdar::list_entry::get_last_access(), libdar::list_entry::get_last_change(), libdar::list_entry::get_last_modif(), and get_second_value().

is_integer_second()

bool libdar::datetime::is_integer_second ( ) const

inline

return true if the datetime is an integer number of second (subsecond part is zero)

Definition at line 134 of file datetime.hpp.

References uni.

is_null()

bool libdar::datetime::is_null ( ) const

inline

return true if the datetime is exactly January 1st, 1970, 0 h 0 mn 0 s

Definition at line 131 of file datetime.hpp.

References libdar::infinint::is_zero(), and val.

nullify()

void libdar::datetime::nullify ( )

inline

set to null (zero)

Definition at line 140 of file datetime.hpp.

References uni, and val.

operator!=()

bool libdar::datetime::operator!= ( const datetime &  ref ) const

inline

Definition at line 89 of file datetime.hpp.

operator+()

datetime libdar::datetime::operator+ ( const datetime &  ref ) const

inline

Definition at line 98 of file datetime.hpp.

operator-()

datetime libdar::datetime::operator- ( const datetime &  ref ) const

inline

Definition at line 97 of file datetime.hpp.

operator<=()

bool libdar::datetime::operator<= ( const datetime &  ref ) const

inline

Definition at line 92 of file datetime.hpp.

operator>()

bool libdar::datetime::operator> ( const datetime &  ref ) const

inline

Definition at line 91 of file datetime.hpp.

operator>=()

bool libdar::datetime::operator>= ( const datetime &  ref ) const

inline

Definition at line 90 of file datetime.hpp.

Member Data Documentation

uni

time_unit libdar::datetime::uni

private

the time unit used to store the subsecond fraction of the timestamp.

Definition at line 153 of file datetime.hpp.

Referenced by datetime(), get_second_value(), get_unit(), is_integer_second(), and nullify().

val

infinint libdar::datetime::val

private

the date expressed in the "uni" time unit

Definition at line 152 of file datetime.hpp.

Referenced by datetime(), is_null(), and nullify().

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The documentation for this class was generated from the following file:

• datetime.hpp