TCP/IP or UDP socket utility functions

Macros
#define	OSIPADDR_ANY   ((OSIPADDR)0)
#define	OSIPADDR_LOCAL   ((OSIPADDR)0x7f000001UL) /* 127.0.0.1 */

Typedefs
typedef unsigned long	OSIPADDR

Functions
int	rtxSocketAccept (OSRTSOCKET socket, OSRTSOCKET *pNewSocket, OSIPADDR *destAddr, int *destPort)
int	rtxSocketAddrToStr (OSIPADDR ipAddr, char *pbuf, size_t bufsize)
int	rtxSocketBind (OSRTSOCKET socket, OSIPADDR addr, int port)
int	rtxSocketClose (OSRTSOCKET socket)
int	rtxSocketConnect (OSRTSOCKET socket, const char *host, int port)
int	rtxSocketConnectTimed (OSRTSOCKET socket, const char *host, int port, int nsecs)
int	rtxSocketCreate (OSRTSOCKET *psocket)
int	rtxSocketCreateUDP (OSRTSOCKET *psocket)
int	rtxSocketGetHost (const char *host, struct in_addr *inaddr)
int	rtxSocketsInit (OSVOIDARG)
int	rtxSocketListen (OSRTSOCKET socket, int maxConnection)
int	rtxSocketParseURL (char *url, char **protocol, char **address, int *port)
int	rtxSocketRecv (OSRTSOCKET socket, OSOCTET *pbuf, size_t bufsize)
int	rtxSocketRecvTimed (OSRTSOCKET socket, OSOCTET *pbuf, size_t bufsize, OSUINT32 secs)
int	rtxSocketSelect (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout)
int	rtxSocketSend (OSRTSOCKET socket, const OSOCTET *pdata, size_t size)
int	rtxSocketSetBlocking (OSRTSOCKET socket, OSBOOL value)
int	rtxSocketStrToAddr (const char *pIPAddrStr, OSIPADDR *pIPAddr)

Detailed Description

Typedef Documentation

OSIPADDR

typedef unsigned long OSIPADDR

The IP address represented as unsigned long value. The most significant 8 bits in this unsigned long value represent the first number of the IP address. The least significant 8 bits represent the last number of the IP address.

Function Documentation

rtxSocketAccept()

int rtxSocketAccept	(	OSRTSOCKET	socket,
		OSRTSOCKET *	pNewSocket,
		OSIPADDR *	destAddr,
		int *	destPort
	)

This function permits an incoming connection attempt on a socket. It extracts the first connection on the queue of pending connections on socket. It then creates a new socket and returns a handle to the new socket. The newly created socket is the socket that will handle the actual connection and has the same properties as original socket. See description of 'accept' socket function for further details.

Parameters

socket	The socket handle created by call to rtxSocketCreate function.
pNewSocket	The pointer to variable to receive the new socket handle.
destAddr	Optional pointer to a buffer that receives the IP address of the connecting entity. It may be NULL.
destPort	Optional pointer to a buffer that receives the port of the connecting entity. It may be NULL.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketAddrToStr()

int rtxSocketAddrToStr	(	OSIPADDR	ipAddr,
		char *	pbuf,
		size_t	bufsize
	)

This function converts an IP address to its string representation.

Parameters

ipAddr	The IP address to be converted.
pbuf	Pointer to the buffer to receive a string with the IP address.
bufsize	Size of the buffer.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketBind()

int rtxSocketBind	(	OSRTSOCKET	socket,
		OSIPADDR	addr,
		int	port
	)

This function associates a local address with a socket. It is used on an unconnected socket before subsequent calls to the rtxSocketConnect or rtxSocketListen functions. See description of 'bind' socket function for further details.

Parameters

socket	The socket handle created by call to rtxSocketCreate function.
addr	The local IP address to assign to the socket.
port	The local port number to assign to the socket.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketClose()

int rtxSocketClose

(

OSRTSOCKET

socket

)

This function closes an existing socket.

Parameters

socket

The socket handle created by call to rtxSocketCreate or rtxSocketAccept function.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketConnect()

int rtxSocketConnect	(	OSRTSOCKET	socket,
		const char *	host,
		int	port
	)

This function establishes a connection to a specified socket. It is used to create a connection to the specified destination. When the socket call completes successfully, the socket is ready to send and receive data. See description of 'connect' socket function for further details.

Parameters

socket	The socket handle created by call to rtxSocketCreate function.
host	The null-terminated string with the IP address in the following format: "NNN.NNN.NNN.NNN", where NNN is a number in the range (0..255).
port	The destination port to connect.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketConnectTimed()

int rtxSocketConnectTimed	(	OSRTSOCKET	socket,
		const char *	host,
		int	port,
		int	nsecs
	)

This function establishes a connection to a specified socket. It is similar to the rtxSocketConnect function except that it will only wait the given number of seconds to establish a connection before giving up.

Parameters

socket	The socket handle created by call to rtxSocketCreate function.
host	The null-terminated string with the IP address in the following format: "NNN.NNN.NNN.NNN", where NNN is a number in the range (0..255).
port	The destination port to connect.
nsecs	Number of seconds to wait before failing.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketCreate()

int rtxSocketCreate

(

OSRTSOCKET *

psocket

)

This function creates a TCP socket.

Parameters

psocket

The pointer to the socket handle variable to receive the handle of new socket.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketGetHost()

int rtxSocketGetHost	(	const char *	host,
		struct in_addr *	inaddr
	)

This function resolves the given host name to an IP address. The resulting address is stored in the given socket address structure.

Parameters

host	Host name to resolve
inaddr	Socket address structure to receive resolved IP address

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketListen()

int rtxSocketListen	(	OSRTSOCKET	socket,
		int	maxConnection
	)

This function places a socket a state where it is listening for an incoming connection. To accept connections, a socket is first created with the rtxSocketCreate function and bound to a local address with the rtxSocketBind function, a maxConnection for incoming connections is specified with rtxSocketListen, and then the connections are accepted with the rtxSocketAccept function. See description of 'listen' socket function for further details.

Parameters

socket	The socket handle created by call to rtxSocketCreate function.
maxConnection	Maximum length of the queue of pending connections.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketParseURL()

int rtxSocketParseURL	(	char *	url,
		char **	protocol,
		char **	address,
		int *	port
	)

This function parses a simple URL of the form <protocol>://<address>:<port> into its individual components. It is assumed that the buffer the URL is provided in is modifiable. Null-terminators are inserted in the buffer to delimit the individual components. If the user needs to use the URL in unparsed form for any other purpose, they will need to make a copy of it before calling this function.

Parameters

url	URL to be parsed. Buffer will be altered.
protocol	Protocol string parsed from the URL.
address	IP address or domain name parsed from URL.
port	Optional port number. Zero if no port provided.

Returns

Zero if parse successful or negative error code.

rtxSocketRecv()

int rtxSocketRecv	(	OSRTSOCKET	socket,
		OSOCTET *	pbuf,
		size_t	bufsize
	)

This function receives data from a connected socket. It is used to read incoming data on sockets. The socket must be connected before calling this function. See description of 'recv' socket function for further details.

Parameters

socket	The socket handle created by call to rtxSocketCreate or rtxSocketAccept function.
pbuf	Pointer to the buffer for the incoming data.
bufsize	Length of the buffer.

Returns

If no error occurs, returns the number of bytes received. Otherwise, the negative value is error code. RTERR_WOULDBLOCK is returned if the socket is non-blocking and 0 bytes were available without blocking.

rtxSocketRecvTimed()

int rtxSocketRecvTimed	(	OSRTSOCKET	socket,
		OSOCTET *	pbuf,
		size_t	bufsize,
		OSUINT32	secs
	)

This function receives data from a connected socket on a timed basis. It is used to read incoming data on sockets. The socket must be connected before calling this function. If no data is available within the given timeout period, an error is returned. See description of 'recv' socket function for further details.

Parameters

socket	The socket handle created by call to rtxSocketCreate or rtxSocketAccept function.
pbuf	Pointer to the buffer for the incoming data.
bufsize	Length of the buffer. secs Amount of time to wait, in seconds, for data to be received.

Returns

If no error occurs, returns the number of bytes received. Otherwise, the negative value is error code.

rtxSocketSelect()

int rtxSocketSelect	(	int	nfds,
		fd_set *	readfds,
		fd_set *	writefds,
		fd_set *	exceptfds,
		struct timeval *	timeout
	)

This function is used for synchronous monitoring of multiple sockets. For more information refer to documentation of the "select" system call.

Parameters

nfds	The highest numbered descriptor to be monitored plus one.
readfds	The descriptors listed in readfds will be watched for whether read would block on them.
writefds	The descriptors listed in writefds will be watched for whether write would block on them.
exceptfds	The descriptors listed in exceptfds will be watched for exceptions.
timeout	Upper bound on amout of time elapsed before select returns.

Returns

Completion status of operation: 0 = success, negative return value is error.

rtxSocketSend()

int rtxSocketSend	(	OSRTSOCKET	socket,
		const OSOCTET *	pdata,
		size_t	size
	)

This function sends data on a connected socket. It is used to write outgoing data on a connected socket. See description of 'send' socket function for further details.

Parameters

socket	The socket handle created by call to rtxSocketCreate or rtxSocketAccept function.
pdata	Buffer containing the data to be transmitted.
size	Length of the data in pdata.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketSetBlocking()

int rtxSocketSetBlocking	(	OSRTSOCKET	socket,
		OSBOOL	value
	)

This function turns blocking mode for a socket on or off.

Parameters

socket	The socket handle created by call to rtxSocketCreate or rtxSocketAccept function.
value	Boolean value. True = turn blocking mode on.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketsInit()

int rtxSocketsInit

(

OSVOIDARG

)

This function initiates use of sockets by an application. This function must be called first before use sockets.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.

rtxSocketStrToAddr()

int rtxSocketStrToAddr	(	const char *	pIPAddrStr,
		OSIPADDR *	pIPAddr
	)

This function converts the string with IP address to a double word representation. The converted address may be used with the rtxSocketBind function.

Parameters

pIPAddrStr	The null-terminated string with the IP address in the following format: "NNN.NNN.NNN.NNN", where NNN is a number in the range (0..255).
pIPAddr	Pointer to the converted IP address.

Returns

Completion status of operation: 0 (0) = success, negative return value is error.