nl::Inet::InterfaceIterator

#include <src/inet/InetInterface.h>

Iterator for the list of system network interfaces.

Summary

Use objects of this class to iterate the list of system network interfaces.

Methods on an individual instance of this class are not thread-safe; however separate instances may be used simultaneously by multiple threads.

On multi-threaded LwIP systems, instances are thread-safe relative to other threads accessing the global LwIP state provided that the other threads hold the LwIP core lock while mutating the list of netifs, and that netif object themselves are never destroyed.

On sockets-based systems, iteration is always stable in the face of changes to the underlying system's interfaces.

On LwIP systems, iteration is stable except in the case where the currently selected interface is removed from the list, in which case iteration ends immediately.

Constructors and Destructors
InterfaceIterator(void)
Constructs an InterfaceIterator object.
~InterfaceIterator(void)
Destroys an InterfaceIterator object.

Protected attributes
mCurIntf
size_t
mCurNetif
struct netif *
mIntfArray
struct if_nameindex *
mIntfFlags
short
mIntfFlagsCached
bool

Public functions
GetInterface(void)
InterfaceId
Deprecated alias for GetInterfaceId(void)
GetInterfaceId(void)
InterfaceId
Returns the network interface id at the current iterator position.
GetInterfaceName(char *nameBuf, size_t nameBufSize)
Get the name of the current network interface.
HasBroadcastAddress(void)
bool
Returns whether the current network interface has a broadcast address.
HasCurrent(void)
bool
Test whether the iterator is positioned on an interface.
IsUp(void)
bool
Returns whether the current network interface is up.
Next(void)
bool
Advance the iterator to the next network interface.
SupportsMulticast(void)
bool
Returns whether the current network interface supports multicast.

Protected functions
GetFlags(void)
short
Returns the ifr_flags value for the current interface.

Protected attributes

mCurIntf

size_t mCurIntf

mCurNetif

struct netif * mCurNetif

mIntfArray

struct if_nameindex * mIntfArray

mIntfFlags

short mIntfFlags

mIntfFlagsCached

bool mIntfFlagsCached

Public functions

GetInterface

InterfaceId GetInterface(
  void
)

Deprecated alias for GetInterfaceId(void)

GetInterfaceId

InterfaceId GetInterfaceId(
  void
)

Returns the network interface id at the current iterator position.

Details
Return Values
INET_NULL_INTERFACEID
if advanced beyond the end of the list.
id
the current network interface id.

GetInterfaceName

INET_ERROR GetInterfaceName(
  char *nameBuf,
  size_t nameBufSize
)

Get the name of the current network interface. 

Writes the name of the network interface as \c NUL terminated text string
at \c nameBuf.

Details
Parameters
[in] nameBuf
region of memory to write the interface name
[in] nameBufSize
size of the region denoted by nameBuf
Return Values
INET_NO_ERROR
successful result, interface name written
INET_ERROR_INCORRECT_STATE
iterator is positioned beyond the end of the list
INET_ERROR_NO_MEMORY
name is too large to be written in buffer
other
another system or platform error

HasBroadcastAddress

bool HasBroadcastAddress(
  void
)

Returns whether the current network interface has a broadcast address.

Details
Returns
true if current network interface has a broadcast address, false if not, or if the iterator is positioned beyond the end of the list.

HasCurrent

bool HasCurrent(
  void
)

Test whether the iterator is positioned on an interface.

Test whether the iterator is positioned on an interface address.

Details
Returns
true if the iterator is positioned on an interface; false if positioned beyond the end of the interface list.
Returns
true if the iterator is positioned on an interface address; false if positioned beyond the end of the address list.

InterfaceIterator

 InterfaceIterator(
  void
)

Constructs an InterfaceIterator object.

Starts the iterator at the first network interface. On some platforms, this constructor may allocate resources recycled by the destructor.

IsUp

bool IsUp(
  void
)

Returns whether the current network interface is up.

Details
Returns
true if current network interface is up, false if not or if the iterator is positioned beyond the end of the list.

Next

bool Next(
  void
)

Advance the iterator to the next network interface. 

Advances the internal iterator to the next network interface or to a position
beyond the end of the interface list.

On multi-threaded LwIP systems, this method is thread-safe relative to other
threads accessing the global LwIP state provided that: 1) the other threads
hold the LwIP core lock while mutating the list of netifs; and 2) netif objects
themselves are never destroyed.

Iteration is stable in the face of changes to the underlying system's
interfaces, *except* in the case of LwIP systems when the currently selected
interface is removed from the list, which causes iteration to end immediately.

Details
Returns
false if advanced beyond the end, else true.

SupportsMulticast

bool SupportsMulticast(
  void
)

Returns whether the current network interface supports multicast.

Details
Returns
true if current network interface supports multicast, false if not, or if the iterator is positioned beyond the end of the list.

~InterfaceIterator

 ~InterfaceIterator(
  void
)

Destroys an InterfaceIterator object.

Recycles any resources allocated by the constructor.

Protected functions

GetFlags

short GetFlags(
  void
)

Returns the ifr_flags value for the current interface.