DNS Class Reference

The DNS class allows fast nonblocking resolution of hostnames and ip addresses. More...

#include <dns.h>

Collaboration diagram for DNS:

[legend]List of all members.

Public Member Functions
	DNS ()
	The default constructor uses dns addresses read from /etc/resolv.conf.
	DNS (std::string dnsserver)
	This constructor accepts a dns server address.
	~DNS ()
	The destructor frees all used structures.
bool	ReverseLookup (std::string ip)
	This method will start the reverse lookup of an ip given in dotted decimal format, e.g.
bool	ForwardLookup (std::string host)
	This method will start the forward lookup of a hostname, e.g.
bool	HasResult ()
	This method will return true when the lookup is completed.
std::string	GetResult ()
	This method returns the result of your query as a string, depending upon wether you called DNS::ReverseLookup() or DNS::ForwardLookup.
int	GetFD ()
	This method returns the file handle used by the dns query socket or zero if the query is invalid for some reason, e.g.
void	SetNS (std::string dnsserver)
Private Member Functions
void	dns_init ()
void	dns_init_2 (const char *dnsserver)
in_addr *	dns_aton4 (const char *const ipstring)
char *	dns_ntoa4 (const in_addr *const ip)
int	dns_getip4 (const char *const name)
int	dns_getip4list (const char *const name)
int	dns_getname4 (const in_addr *const ip)
char *	dns_getresult (const int fd)
in_addr *	dns_aton4_s (const char *const ipstring, in_addr *const ip)
char *	dns_ntoa4_s (const in_addr *const ip, char *const result)
char *	dns_getresult_s (const int fd, char *const result)
in_addr *	dns_aton4_r (const char *const ipstring)
char *	dns_ntoa4_r (const in_addr *const ip)
char *	dns_getresult_r (const int fd)
Private Attributes
in_addr *	binip
char *	result
int	t
unsigned int	fd

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Detailed Description

The DNS class allows fast nonblocking resolution of hostnames and ip addresses.

It is based heavily upon firedns by Ian Gulliver.

Definition at line 35 of file dns.h.

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Constructor & Destructor Documentation

DNS::DNS (   )

The default constructor uses dns addresses read from /etc/resolv.conf. Please note that it will re-read /etc/resolv.conf for each copy of the class you instantiate, causing disk access and slow lookups if you create a lot of them. Consider passing the constructor a server address as a parameter instead.

DNS::DNS (  std::string  dnsserver  )

This constructor accepts a dns server address. The address must be in dotted decimal form, e.g. 1.2.3.4.

DNS::~DNS (   )

The destructor frees all used structures.

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Member Function Documentation

in_addr* DNS::dns_aton4 (  const char *const  ipstring  )  [private]

in_addr* DNS::dns_aton4_r (  const char *const  ipstring  )  [private]

in_addr* DNS::dns_aton4_s (  const char *const  ipstring, in_addr *const  ip )  [private]

int DNS::dns_getip4 (  const char *const  name  )  [private]

int DNS::dns_getip4list (  const char *const  name  )  [private]

int DNS::dns_getname4 (  const in_addr *const  ip  )  [private]

char* DNS::dns_getresult (  const int  fd  )  [private]

char* DNS::dns_getresult_r (  const int  fd  )  [private]

char* DNS::dns_getresult_s (  const int  fd, char *const  result )  [private]

void DNS::dns_init (   )  [private]

void DNS::dns_init_2 (  const char *  dnsserver  )  [private]

char* DNS::dns_ntoa4 (  const in_addr *const  ip  )  [private]

char* DNS::dns_ntoa4_r (  const in_addr *const  ip  )  [private]

char* DNS::dns_ntoa4_s (  const in_addr *const  ip, char *const  result )  [private]

bool DNS::ForwardLookup (  std::string  host  )

This method will start the forward lookup of a hostname, e.g. www.inspircd.org, and returns true if the lookup was successfully initiated.

int DNS::GetFD (   )

This method returns the file handle used by the dns query socket or zero if the query is invalid for some reason, e.g. the dns server not responding.

std::string DNS::GetResult (   )

This method returns the result of your query as a string, depending upon wether you called DNS::ReverseLookup() or DNS::ForwardLookup.

bool DNS::HasResult (   )

This method will return true when the lookup is completed. It uses poll internally to determine the status of the socket.

bool DNS::ReverseLookup (  std::string  ip  )

This method will start the reverse lookup of an ip given in dotted decimal format, e.g. 1.2.3.4, and returns true if the lookup was successfully initiated.

void DNS::SetNS (  std::string  dnsserver  )

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Member Data Documentation

in_addr* DNS::binip [private]

Definition at line 38 of file dns.h.

unsigned int DNS::fd [private]

Definition at line 42 of file dns.h.

char* DNS::result [private]

Definition at line 39 of file dns.h.

int DNS::t [private]

Definition at line 40 of file dns.h.

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

• dns.h

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