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.
bool	HasResult (int fd)
	This method will return true if the lookup's fd matches the one provided.
std::string	GetResult ()
	This method returns the result of your query as a string, depending upon wether you called DNS::ReverseLookup() or DNS::ForwardLookup.
std::string	GetResultIP ()
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
char	localbuf [1024]
int	t
int	myfd

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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.

std::string DNS::GetResultIP (   )

bool DNS::HasResult (  int  fd  )

This method will return true if the lookup's fd matches the one provided.

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.

char DNS::localbuf[1024] [private]

Definition at line 40 of file dns.h.

int DNS::myfd [private]

Definition at line 43 of file dns.h.

char* DNS::result [private]

Definition at line 39 of file dns.h.

int DNS::t [private]

Definition at line 41 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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