pcpp::internal::PcapHandle Class Reference

A wrapper class for pcap_t* which is the libpcap packet capture descriptor. This class is used to manage the lifecycle of the pcap_t* object. More...

#include <PcapDevice.h>

Public Member Functions
constexpr	PcapHandle () noexcept=default
	Creates an empty handle.
	PcapHandle (pcap_t *pcapDescriptor) noexcept
	Creates a handle from the provided pcap descriptor. More...
bool	isValid () const noexcept
pcap_t *	get () const noexcept
pcap_t *	release () noexcept
	Releases ownership of the handle and returns the pcap descriptor. More...
void	reset (pcap_t *pcapDescriptor=nullptr) noexcept
	Replaces the managed handle with the provided one. More...
char const *	getLastError () const noexcept
	Helper function to retrieve a view of the last error string for this handle. More...
bool	setFilter (std::string const &filter)
	Sets a filter on the handle. Only packets that match the filter will be captured by the handle. More...
bool	clearFilter ()
	Clears the filter currently set on the handle. More...
bool	getStatistics (PcapStats &stats) const
	Retrieves statistics from the pcap handle. More...
	operator bool () const noexcept

Detailed Description

A wrapper class for pcap_t* which is the libpcap packet capture descriptor. This class is used to manage the lifecycle of the pcap_t* object.

Constructor & Destructor Documentation

PcapHandle()

pcpp::internal::PcapHandle::PcapHandle ( pcap_t *  pcapDescriptor )

explicitnoexcept

Creates a handle from the provided pcap descriptor.

Parameters

pcapDescriptor

The pcap descriptor to wrap.

Member Function Documentation

clearFilter()

bool pcpp::internal::PcapHandle::clearFilter

(

)

Clears the filter currently set on the handle.

Returns

True if the filter was removed successfully or if no filter was set, false otherwise.

get()

pcap_t* pcpp::internal::PcapHandle::get ( ) const

inlinenoexcept

Returns

The underlying pcap descriptor.

getLastError()

char const* pcpp::internal::PcapHandle::getLastError ( ) const

noexcept

Helper function to retrieve a view of the last error string for this handle.

Returns

A null-terminated view of the last error string.

Remarks

The returned view is only valid until the next call to a pcap function.

getStatistics()

bool pcpp::internal::PcapHandle::getStatistics

(

PcapStats &

stats

)

const

Retrieves statistics from the pcap handle.

The function internally calls pcap_stats() to retrieve the statistics and only works on live devices.

Parameters

stats

Structure to store the statistics.

Returns

True if the statistics were retrieved successfully, false otherwise.

isValid()

bool pcpp::internal::PcapHandle::isValid ( ) const

inlinenoexcept

Returns

True if the handle is not null, false otherwise.

operator bool()

pcpp::internal::PcapHandle::operator bool ( ) const

inlineexplicitnoexcept

Returns

True if the handle is not null, false otherwise.

release()

pcap_t* pcpp::internal::PcapHandle::release ( )

noexcept

Releases ownership of the handle and returns the pcap descriptor.

Returns

The pcap descriptor or nullptr if no handle is owned.

reset()

void pcpp::internal::PcapHandle::reset ( pcap_t *  pcapDescriptor = nullptr )

noexcept

Replaces the managed handle with the provided one.

Parameters

pcapDescriptor

A new pcap descriptor to manage.

Remarks

If the handle contains a non-null descriptor it will be closed.

setFilter()

bool pcpp::internal::PcapHandle::setFilter

(

std::string const &

filter

)

Sets a filter on the handle. Only packets that match the filter will be captured by the handle.

The filter uses Berkeley Packet Filter (BPF) syntax (http://biot.com/capstats/bpf.html).

Parameters

[in]

filter

The filter to set in Berkeley Packet Filter (BPF) syntax.

Returns

True if the filter was set successfully, false otherwise.