Kea 2.5.8
isc::dns::Serial Class Reference

This class defines DNS serial numbers and serial arithmetic. More...

#include <serial.h>

Public Member Functions

 Serial (const Serial &other)
 Copy constructor.
 
 Serial (uint32_t value)
 Constructor with value.
 
uint32_t getValue () const
 Returns the uint32_t representation of this serial value.
 
bool operator!= (const Serial &other) const
 Returns true if the serial values are not equal.
 
Serial operator+ (const Serial &other) const
 Adds the given value to the serial number.
 
Serial operator+ (uint32_t other_val) const
 Adds the given value to the serial number.
 
bool operator< (const Serial &other) const
 Returns true if the serial value of this serial is smaller than the other, according to serial arithmetic as described in RFC 1982.
 
bool operator<= (const Serial &other) const
 Returns true if the serial value of this serial is equal to or smaller than the other, according to serial arithmetic as described in RFC 1982.
 
Serialoperator= (const Serial &other)
 Direct assignment from other Serial.
 
void operator= (uint32_t value)
 Direct assignment from value.
 
bool operator== (const Serial &other) const
 Returns true if the serial values are equal.
 
bool operator> (const Serial &other) const
 Returns true if the serial value of this serial is greater than the other, according to serial arithmetic as described in RFC 1982.
 
bool operator>= (const Serial &other) const
 Returns true if the serial value of this serial is equal to or greater than the other, according to serial arithmetic as described in RFC 1982.
 

Detailed Description

This class defines DNS serial numbers and serial arithmetic.

DNS Serial number are in essence unsigned 32-bits numbers, with one catch; they should be compared using sequence space arithmetic. So given that they are 32-bits; as soon as the difference between two serial numbers is greater than 2147483647 (2^31 - 1), the lower number (in plain comparison) is considered the higher one.

In order to do this as transparently as possible, these numbers are stored in the Serial class, which overrides the basic comparison operators.

In this specific context, these operations are called 'serial number arithmetic', and they are defined in RFC 1982.

Note
RFC 1982 defines everything based on the value SERIAL_BITS. Since the serial number has a fixed length of 32 bits, the values we use are hard-coded, and not computed based on variable bit lengths.

Definition at line 41 of file serial.h.

Constructor & Destructor Documentation

◆ Serial() [1/2]

isc::dns::Serial::Serial ( uint32_t  value)
inlineexplicit

Constructor with value.

Parameters
valueThe uint32_t value of the serial

Definition at line 46 of file serial.h.

◆ Serial() [2/2]

isc::dns::Serial::Serial ( const Serial other)
inline

Copy constructor.

Definition at line 49 of file serial.h.

Member Function Documentation

◆ getValue()

uint32_t isc::dns::Serial::getValue ( ) const
inline

Returns the uint32_t representation of this serial value.

Returns
The uint32_t value of this Serial

Definition at line 67 of file serial.h.

Referenced by operator!=(), operator+(), operator<(), isc::dns::operator<<(), operator=(), and operator==().

◆ operator!=()

bool isc::dns::Serial::operator!= ( const Serial other) const

Returns true if the serial values are not equal.

Returns
True if the values are not equal

Definition at line 20 of file serial.cc.

References getValue().

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◆ operator+() [1/2]

Serial isc::dns::Serial::operator+ ( const Serial other) const

Adds the given value to the serial number.

If this would make the number greater than 2^32-1, it is 'wrapped'.

Note
According to the specification, an addition greater than MAX_SERIAL_INCREMENT is undefined. We do NOT catch this error (so as not to raise exceptions), but this behaviour remains undefined.
Parameters
otherThe Serial to add
Returns
The result of the addition

Definition at line 59 of file serial.cc.

References getValue().

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◆ operator+() [2/2]

Serial isc::dns::Serial::operator+ ( uint32_t  other_val) const

Adds the given value to the serial number.

If this would make the number greater than 2^32-1, it is 'wrapped'.

Note
According to the specification, an addition greater than MAX_SERIAL_INCREMENT is undefined. We do NOT catch this error (so as not to raise exceptions), but this behaviour remains undefined.
Parameters
other_valThe uint32_t value to add
Returns
The result of the addition

Definition at line 52 of file serial.cc.

References isc::dns::MAX_SERIAL_VALUE.

◆ operator<()

bool isc::dns::Serial::operator< ( const Serial other) const

Returns true if the serial value of this serial is smaller than the other, according to serial arithmetic as described in RFC 1982.

Parameters
otherThe Serial to compare to
Returns
True if this is smaller than the given value

Definition at line 24 of file serial.cc.

References getValue(), and isc::dns::MAX_SERIAL_INCREMENT.

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◆ operator<=()

bool isc::dns::Serial::operator<= ( const Serial other) const

Returns true if the serial value of this serial is equal to or smaller than the other, according to serial arithmetic as described in RFC 1982.

Parameters
otherThe Serial to compare to
Returns
True if this is smaller than or equal to the given value

Definition at line 36 of file serial.cc.

◆ operator=() [1/2]

Serial & isc::dns::Serial::operator= ( const Serial other)
inline

Direct assignment from other Serial.

Parameters
otherThe Serial to assign the value from

Definition at line 54 of file serial.h.

References getValue().

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◆ operator=() [2/2]

void isc::dns::Serial::operator= ( uint32_t  value)
inline

Direct assignment from value.

Parameters
valuethe uint32_t value to assign

Definition at line 62 of file serial.h.

◆ operator==()

bool isc::dns::Serial::operator== ( const Serial other) const

Returns true if the serial values are equal.

Returns
True if the values are equal

Definition at line 15 of file serial.cc.

References getValue().

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◆ operator>()

bool isc::dns::Serial::operator> ( const Serial other) const

Returns true if the serial value of this serial is greater than the other, according to serial arithmetic as described in RFC 1982.

Parameters
otherThe Serial to compare to
Returns
True if this is greater than the given value

Definition at line 42 of file serial.cc.

◆ operator>=()

bool isc::dns::Serial::operator>= ( const Serial other) const

Returns true if the serial value of this serial is equal to or greater than the other, according to serial arithmetic as described in RFC 1982.

Parameters
otherThe Serial to compare to
Returns
True if this is greater than or equal to the given value

Definition at line 47 of file serial.cc.


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