G3D::NetworkDevice Class Reference

Abstraction of network (socket) functionality. More...

Classes
class	EthernetAdapter
	Description of an ethernet or wireless ethernet adapter. More...

Public Member Functions
	~NetworkDevice ()
const Array< EthernetAdapter > &	adapterArray () const
	Returns the available ethernet adapters for the current machine that are online. More...
const Array< uint32 > &	broadcastAddressArray () const
	Returns the (unique) IP addresses for UDP broadcasting extracted from adapterArray(). More...
void	describeSystem (TextOutput &t)
	Prints a human-readable description of this machine to the text output stream. More...
void	describeSystem (String &s)
void	localHostAddresses (Array< NetAddress > &array) const
	There is often more than one address for the local host. More...
String	localHostName () const
	Returns the name (or one of the names) of this computer. More...

Static Public Member Functions
static void	cleanup ()
	Shuts down the network device (destroying the global instance). More...
static String	formatIP (uint32 ip)
	Prints an IP address to a string. More...
static String	formatMAC (const uint8 mac[6])
	Prints a MAC address to a string. More...
static NetworkDevice *	instance ()
	Returns nullptr if there was a problem initializing the network. More...

Friends
class	Conduit
class	LightweightConduit
class	NetListener
class	ReliableConduit

Detailed Description

Abstraction of network (socket) functionality.

An abstraction over sockets that provides a message-based network infrastructure optimized for sending many small (~500 bytes) messages. All functions always return immediately.

Create only one NetworkDevice per process (a WinSock restriction).

NetworkDevice is technically not thread safe. However, as long as you use different conduits on different threads (or lock conduits before sending), you will encounter no problems sharing the single NetworkDevice across multiple threads. That is, do not invoke the same Conduit's send or receive method on two threads at once.

This assumes that the underlying WinSock/BSD sockets implementation is thread safe. That is not guaranteed, but in practice seems to always be true (see http://tangentsoft.net/wskfaq/intermediate.html#threadsafety)

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IP networks use "network byte order" (big-endian) for communicating integers. "Host byte order" is the endian-ness of the local machine (typically little-endian; see System::endian). The C functions htonl() and ntohl() convert 32-bit values between these formats. G3D only ever exposes host byte order, so programmers rarely need to be aware of the distinction.

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These classes abstract networking from the socket level to a serialized messaging style that is more appropriate for games. The performance has been tuned for sending many small messages. The message protocol contains a header that prevents them from being used with raw UDP/TCP (e.g. connecting to an HTTP server).

LightweightConduit and ReliableConduits have different interfaces because they have different semantics. You would never want to interchange them without rewriting the surrounding code.

NetworkDevice creates conduits because they need access to a global log pointer and because I don't want non-reference counted conduits being created.

Be careful with threads and reference counting. The reference counters are not threadsafe, and are also not updated correctly if a thread is explicitly killed. Since the conduits will be passed by const XConduitRef& most of the time this doesn't appear as a major problem. With non-blocking conduits, you should need few threads anyway.

LightweightConduits preceed each message with a 4-byte host order unsigned integer that is the message type. This does not appear in the message serialization/deserialization.

ReliableConduits preceed each message with two 4-byte host order unsigned integers. The first is the message type and the second indicates the length of the rest of the data. The size does not include the size of the header itself. The minimum message is 9 bytes:a 4-byte type, a 4-byte header equal to "1", and one byte of data.

Deprecated:

Constructor & Destructor Documentation

~NetworkDevice()

G3D::NetworkDevice::~NetworkDevice

(

)

Member Function Documentation

adapterArray()

const Array<EthernetAdapter>& G3D::NetworkDevice::adapterArray ( ) const

inline

Returns the available ethernet adapters for the current machine that are online.

Does not include the loopback adapter for localhost.

broadcastAddressArray()

const Array<uint32>& G3D::NetworkDevice::broadcastAddressArray ( ) const

inline

Returns the (unique) IP addresses for UDP broadcasting extracted from adapterArray().

All are in host byte order.

cleanup()

static void G3D::NetworkDevice::cleanup ( )

static

Shuts down the network device (destroying the global instance).

describeSystem() [1/2]

void G3D::NetworkDevice::describeSystem

(

TextOutput &

t

)

Prints a human-readable description of this machine to the text output stream.

describeSystem() [2/2]

void G3D::NetworkDevice::describeSystem

(

String &

s

)

formatIP()

static String G3D::NetworkDevice::formatIP ( uint32  ip )

static

Prints an IP address to a string.

Parameters

ip	In host byte order.

formatMAC()

static String G3D::NetworkDevice::formatMAC ( const uint8  mac[6] )

static

Prints a MAC address to a string.

instance()

static NetworkDevice* G3D::NetworkDevice::instance ( )

static

Returns nullptr if there was a problem initializing the network.

localHostAddresses()

void G3D::NetworkDevice::localHostAddresses

(

Array< NetAddress > &

array

)

const

There is often more than one address for the local host.

This returns all of them.

Deprecated:

Use adapterArray()

localHostName()

String G3D::NetworkDevice::localHostName

(

)

const

Returns the name (or one of the names) of this computer.

Friends And Related Function Documentation

Conduit

friend class Conduit

friend

LightweightConduit

friend class LightweightConduit

friend

NetListener

friend class NetListener

friend

ReliableConduit

friend class ReliableConduit

friend