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GLAST/LAT > DAQ and FSW > FSW > Doxygen Index > NMSG / V4-0-1

Constituent: nmsg     Tag: sun-gcc

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nmsgLib.c File Reference

Routines for handling formatted network messages. More...

#include "NMSG/nmsgLib.h"
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <pthread.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>

Include dependency graph for nmsgLib.c:

Functions
int	nmsgCheck (void *hndl)
	Check a network connection handle.
int	nmsgClose (void *hndl, int force)
	Terminate a message client or server.
int	nmsgConnect (void **hndl, const char *node, int port)
	Connect to a message server.
int	nmsgConnectAsy (void **hndl, const char *node, int port, int prio, nmsgConnCB_t connRtn, nmsgDiscCB_t discRtn, void *uParm)
	Connect asynchronously (robustly) to a message server.
const char *	nmsgErrorMsg (int status)
	Obtain the text of an error message.
void	nmsgErrorReport (int status, const char *func)
	Display an error message.
int	nmsgListen (void **hndl, int port, int maxConn, int maxData, int prio, nmsgConnCB_t connRtn, nmsgDiscCB_t discRtn, nmsgRcveCB_t rcveRtn, void *uParm)
	Establish a message server.
int	nmsgRemoteIP (void *hndl, int *ip)
	Get the IP address of the remote end.
int	nmsgSend (void *hndl, nmsgBuff_t *msg)
	Send a message and return immediately.
int	nmsgSendW (void *hndl, nmsgBuff_t *msg, nmsgBuff_t **replyP, nmsgBuff_t *reply, int maxData)
	Send a message and receive reply.
int	nmsgStats (void *hndl, nmsgStats_t *stats)
	Get connection statistics.
int	nmsgWait (void *hndl, nmsgBuff_t **replyP, nmsgBuff_t *reply, int maxData)
	Wait for a reply to a sent message.

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Detailed Description

Routines for handling formatted network messages.

Author:

Owen H Saxton

Id

nmsgLib.c,v 1.12 2008/09/08 20:04:01 saxton Exp

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Function Documentation

int nmsgCheck (  void *  hndl  )

Check a network connection handle. This routine checks whether a network handle is valid or not. Parameters: hndl  The handle for the connection. Return values: 1  The handle is valid. 0  The handle is invalid.

int nmsgClose (  void *  hndl, int  force )

Terminate a message client or server. This routine closes a network connection or stops a network server. Parameters: hndl  The handle of the connection or server. force  For a client connection, if TRUE, the connection is closed even if another task is in the process of sending a message. If FALSE, the closing waits until any activity has ceased. Not used for a server. Return values: NMSG_SUCCESS  Success. NMSG_INVHNDL  Invalid network handle.

int nmsgConnect (  void **  hndl, const char *  node, int  port )

Connect to a message server. This routine establishes a network connection to a message server. Parameters: hndl  The address of a pointer to receive the identifying handle for the network connection. node  The address of the name of the node containing the message server. port  The port number on which to establish the connection. Return values: NMSG_SUCCESS  The connection was established successfully. NMSG_NOMEMORY  Insuffucuent memory available. NMSG_UNKNHOST  Host is unknown. NMSG_NOSEMCRE  Unable to create sync. semaphore (VxWorks) NMSG_xxx  Various connection errors.

int nmsgConnectAsy (  void **  hndl, const char *  node, int  port, int  prio, nmsgConnCB_t  connRtn, nmsgDiscCB_t  discRtn, void *  uParm )

Connect asynchronously (robustly) to a message server. This routine establishes a robust network connection to a message server. The connection is done asynchronously, and the attempt is retried periodically if the initial attempt fails, or if the connection is broken. Parameters: hndl  The address of a pointer to receive the identifying handle for the network connection. node  The address of the name of the node containing the message server. port  The port number on which to establish the connection. prio  The priority of the connection task, where applicable. If 0, the default value (100) is used. connRtn  The address of a routine to be called when the connection has been made. discRtn  The address of a routine to be called when the connection is broken. uParm  A parameter to be passed to the connect and disconnect callback routines. Return values: NMSG_SUCCESS  The connection was established successfully. NMSG_NOMEMORY  Insuffucuent memory available. NMSG_UNKNHOST  Host is unknown. NMSG_NOSEMCRE  Unable to create sync. semaphore (VxWorks) NMSG_NOTASKCR  Unable to spawn connection task.

const char* nmsgErrorMsg (  int  status  )

Obtain the text of an error message. This routine returns a pointer to the message corresponding to a given NMSG status code. Parameters: status  The NMSG status code. Returns: The address of the corresponding message text.

void nmsgErrorReport (  int  status, const char *  func )

Display an error message. This routine outputs to stderr the message corresponding to a given NMSG status code. Parameters: status  The NMSG status code. func  The function name to be displayed at the start of the message.

int nmsgListen (  void **  hndl, int  port, int  maxConn, int  maxData, int  prio, nmsgConnCB_t  connRtn, nmsgDiscCB_t  discRtn, nmsgRcveCB_t  rcveRtn, void *  uParm )

Establish a message server. This routine establishes a network message server (listener). Parameters: hndl  The address of a pointer to receive the identifying handle for the network listener. port  The port number on which to establish the server. maxConn  The maximum number of concurrent connections that the server will allow. maxData  The maximum number of data bytes that can be transferred in a single message. prio  The priority of the listener (server) and receiver tasks, where applicable. If 0, the default value (100) is used. connRtn  The address of a routine to be called when a new connection has been made. The connection will be rejected if this routine returns ERROR status. discRtn  The address of a routine to be called when a connection is broken. rcveRtn  The address of a routine to be called whenever a message is received. uParm  A parameter to be passed to the connect, disconnect and receive callback routines. Return values: NMSG_SUCCESS  The connection was established successfully. NMSG_NOMEMORY  Insuffucuent memory available. NMSG_NOTASKCR  Unable to spawn listener task. NMSG_xxx  Various system errors.

int nmsgRemoteIP (  void *  hndl, int *  ip )

Get the IP address of the remote end. This routine returns the IP address of the remote end of a connection. It can be used on either end of a connection. Parameters: hndl  The handle for the connection. ip  The addressof an integer to receive the IP address. Return values: NMSG_SUCCESS  Success. NMSG_INVHNDL  Invalid network handle.

int nmsgSend (  void *  hndl, nmsgBuff_t *  msg )

Send a message and return immediately. This routine sends a message on a network connection and returns without waiting for a reply. Parameters: hndl  The handle for the connection. msg  The address of message to be sent. It must be formatted using the nmsgBuff_t structure type. Return values: NMSG_SUCCESS  Success. NMSG_INVHNDL  Invalid network handle. NMSG_NOTCONN  Not connected to server. NMSG_INVSEMA  Invalid semaphore. NMSG_DISCONN  Server connection was broken.

int nmsgSendW (  void *  hndl, nmsgBuff_t *  msg, nmsgBuff_t **  replyP, nmsgBuff_t *  reply, int  maxData )

Send a message and receive reply. This routine sends a message on a network connection and waits for a reply. Parameters: hndl  The handle for the connection. msg  The address of message to be sent. It must be formatted using the nmsgBuff_t structure type. replyP  The address of a pointer to receive the address of the reply. If a reply area is supplied and it is big enough, this will be the address of this area. Otherwise a sufficiently large reply area is allocated and its address returned here. In this latter case, the memory must be relinquished using free() after it is no longer needed. reply  The address of an area to receive the reply to the message, or NULL if no area is to be used. maxData  The maximum number of data bytes that can be put into the supplied reply area. Return values: NMSG_SUCCESS  Success. NMSG_INVHNDL  Invalid network handle. NMSG_NOTCONN  Not connected to server. NMSG_INVSEMA  Invalid semaphore. NMSG_DISCONN  Server connection was broken.

int nmsgStats (  void *  hndl, nmsgStats_t *  stats )

Get connection statistics. This routine returns a block of connection statistics containing the number of connects, disconnects, messages sent/received, bytes sent and bytes received. Parameters: hndl  The handle for the connection. stats  The address of an area to receive the statistics block. Return values: NMSG_SUCCESS  Success. NMSG_INVHNDL  Invalid network handle.

int nmsgWait (  void *  hndl, nmsgBuff_t **  replyP, nmsgBuff_t *  reply, int  maxData )

Wait for a reply to a sent message. This routine waits for a reply to a previously sent message. Parameters: hndl  The handle for the connection. replyP  The address of a pointer to receive the address of the reply. If a reply area is supplied and it is big enough, this will be the address of this area. Otherwise a sufficiently large reply area is allocated and its address returned here. In this latter case, the memory must be relinquished using free() after it is no longer needed. reply  The address of an area to receive the reply to the message, or NULL if no area is to be used. maxData  The maximum number of data bytes that can be put into the supplied reply area. Return values: NMSG_SUCCESS  Success. NMSG_INVHNDL  Invalid network handle. NMSG_NOTCONN  Not connected to server. NMSG_INVSEMA  Invalid semaphore. NMSG_DISCONN  Server connection was broken.

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