www.pudn.com > vxWorks_Lab.rar > pipeServerSig.c

/* pipeServerSig.c - reads requests over pipe */ 
/* Installs signal handlers for some exceptions. */ 
 
#include "vxWorks.h" 
#include "pipeDrv.h" 
#include "taskLib.h" 
#include "ioLib.h" 
#include "logLib.h" 
#include "sigLib.h" 
 
typedef struct 
	{ 
	VOIDFUNCPTR routine; 
	int arg; 
	} MSG_REQUEST; 
 
#define TASK_PRI						254 
#define TASK_STACK 20000  /* server stack space */ 
#define PIPE_NAME						"/pipe/server" 
#define NUM_MSGS						10 
 
int pipeFd; 
 
LOCAL void pipeServer (); 
 
/************************************************** 
* sigHandler -- Returns task to known state. 
* 
* Called when signal posted. 
* 
*/ 
 
 void sigHandler (	int sig) 
	{ 
	logMsg ("Signal %d received. Restarting" 
				" server\n", sig, 0,0,0,0,0); 
	taskRestart (0); 
	} 
 
/************************************************** 
* serverStart -- Initializes a server task to 
* execute functons at a low priority. Uses pipes as 
* the communication mechanism. 
* 
* RETURNS: OK or ERROR on failure. 
*/ 
 
STATUS serverStart (void) 
	{ 
	/* Create the pipe device */ 
 
	if (pipeDevCreate (PIPE_NAME, NUM_MSGS,  
			sizeof (MSG_REQUEST)) == ERROR) 
		return (ERROR); 
	 
	/* Open the pipe */ 
 
	if ((pipeFd = open (PIPE_NAME, UPDATE, 0)) 
			== ERROR) 
		return (ERROR); 
	 
	/* Spawn the server task */ 
 
	if (taskSpawn ("tServer", TASK_PRI, 0, 
						TASK_STACK, (FUNCPTR)pipeServer, 
						0,0,0,0,0,0,0,0,0,0) == ERROR) 
		{ 
		close (pipeFd); 
		return (ERROR); 
		} 
	 
	return (OK); 
	} 
 
/************************************************** 
* serverSend -- Sends a request to the server to 
* execute a function at the server's priority. 
* 
* RETURNS: OK or ERROR on failure. 
*/ 
 
STATUS serverSend  
	( 
	VOIDFUNCPTR routine, 
	int arg 
	) 
	{ 
	MSG_REQUEST msgRequest; 
	int status; 
 
	/* Initialize the message structure */ 
 
	msgRequest.routine = routine; 
	msgRequest.arg = arg; 
 
	/* Send the message and return the results */ 
 
	status = write (pipeFd, (char *)&msgRequest, 
						sizeof (MSG_REQUEST)); 
 
	return ((status == sizeof (MSG_REQUEST)) ? 
				OK : ERROR); 
	} 
 
/************************************************** 
* pipeServer -- Server task which reads from a pipe 
* and executes the function passed in the 
* MSG_REQUEST data structure. 
* 
*/ 
 
LOCAL void pipeServer (void) 
	{ 
	MSG_REQUEST msgRequest; 
 
	signal (SIGBUS,  sigHandler); 
	signal (SIGILL,  sigHandler); 
	signal (SIGSEGV, sigHandler);  
 
	while (read (pipeFd, (char *)&msgRequest,  
					 sizeof (MSG_REQUEST)) > 0) 
		(*msgRequest.routine) (msgRequest.arg); 
	}