netrom.c

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/* netrom.c - XLNT Design's netrom backend library */

/* Copyright 1984-1995 Wind River Systems, Inc. */
#include "copyright_wrs.h"

/*
modification history
--------------------
01h,01jul98,c_c  Fixed an include Pb on HP.
01g,01jul98,c_c  Ported to backend V2 API.
01f,20mar98,pcn  Changed FALSE to ERROR.
01e,03mar98,c_c  Removed clnt_soc.h for WIN32.
01d,03feb98,dbt  corrected clntudp_create() call.
01c,28jun96,c_s   just include <fcntl.h>; this is more portable.
01b,15jan96,elp	  added external function variable (WIN32)
		  + modified netromInit() to initialize this variable.
01a,27sep95,tpr	  written, inspired from /backend/wdbrpc/wdbrpc.c version 02m.
*/

/*
DESCRIPTION
This backend utilizes the XLNT Designs NetRom rom emulator to form a
communication path the target running the WDB agent.  It requires a
special netRom driver to be configured into the target agent.
*/

/* includes */

#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <rpc/rpc.h>
#include <sys/socket.h>
#include <sys/time.h>
#ifndef WIN32
#ifdef SUN4_SOLARIS2
#include <rpc/clnt_soc.h>
#endif
#endif

#include "tgtlib.h"
#include "wpwrlog.h"
#include "host.h"
#include "bkendlib.h"

/* defines */

/* forward declarations */

extern STATUS rpcCoreInit (CLIENT *, u_int, u_int, TGT_OPS *);

/* locals */

LOCAL u_int netromTimeout       = BKEND_TIMEOUT;/* backend timeout */
LOCAL u_int netromRetry         = BKEND_RESEND; /* backend resend number */

static FLAG_DESC netromFlags [] =
    {
	{
    	"-Btimeout","-Bt", (PARSE_RTN) flagInt,    &netromTimeout,
	"-Bt[imeout] value\tNetRom Backend request timeout (default 1 sec.)."
	},

	{
    	"-Bresend", "-Br", (PARSE_RTN) flagInt,    &netromRetry,
	"-Br[esend] number\tNetRom Backend request re-send number (default 3)."
	},

	{NULL, NULL, NULL, NULL, NULL}		/* End Of Record delimiter */
    };

/*******************************************************************************
*
* netromFlagsGet - Get the supported flags for this backend
*
* This function is called by the target server when it wants to get the flags
* which are supported by the currently attached backend. The following options
* can be set trough command line parameters.
*
* <timeout> is the time out duration to use for the communication with the
* WDB target agent. This input argument is set when the target server is
* started with the option -Bt. Otherwise set to zero.
*
* <recallNum> is the maximun number of time that a request is re-sent before
* to admit the communication link is broken. Set when the target server is
* started with the option -Br, otherwise reset to zero.
*
* Here we return our supported flags.
*
*/

DLL_EXPORT FLAG_DESC *  netromFlagsGet (void)
    {
    return (FLAG_DESC *) netromFlags;
    }

/*******************************************************************************
*
* netromInitialize - initialize the backend interface
*
* This function is called by the target server when it wants to attach this
* backend. Three input arguments are accepted:
*
* <tgtName> is a pointer to a string that handles either the name or the
* internet address (in dotted-decimal * format) of the target board. 
*
* <pTgtOps> is a pointer to TGT_OPS structure (defined in tgtlib.h file).
* This structure handles function pointers used by the target server to call
* a backend function. The backend attachment is performed by filling this
* structure with the backend function address. 
*
* <pBkInfo> is a structure to fill for the target server to know if the backend
* exports a selectable file descriptor, a select-like function, or nothing for
* the asynchronous event notification. 
* Remember that the target server now dedicates a thread to the event
* notification.
*
* This function initializes the backend. It creates the backend client, resets
* the udp datagram sequence number and fills the TGT_OPS structure with
* the information describing the backend and returns a pointer to this 
* structure.
*
* CAVEAT: its name is built from the file name concatenated with the string
*         "Initialize". This is compulsory.
* 
* RETURNS: TRUE if the backend is properly initialized, otherwise FALSE.
*/

DLL_EXPORT STATUS netromInitialize
    (
    char *		tgtName,	/* target name to connect to */
    TGT_OPS *		pTgtOps,	/* backend function */
    BKEND_INFO *	pBkInfo		/* Backend info and select method */
    )
    {
    CLIENT *		pClnt;		/* target client */
    u_long		addr;		/* target address: long int format */
    struct sockaddr_in	dest_addr;	/* target address information */
    struct hostent *	dest_host;	/* target address */
    int			wdbSocket;	/* backend client socket */
    struct timeval 	tv;		/* connection timeout */
    u_int		resendCnt;	/* connection re-send counter */


    /* clear dest_addr */

    memset ((void *) &dest_addr, 0x00, sizeof (dest_addr));

    /* convert <tgtName> into the target board Internet address */

    if ((dest_host = (struct hostent *) gethostbyname (tgtName)) == NULL)
	{
	if ((addr = inet_addr (tgtName)) == (u_long) ERROR)
	    {
	    errno = WTX_ERR_SVR_TARGET_UNKNOWN;
	    wpwrLogErr ("Target %s unknown. Attach failed.\n", tgtName);
	    return (ERROR);
	    }
	dest_addr.sin_addr.s_addr = addr;
	}
    else
	dest_addr.sin_addr.s_addr = * ((u_long *) dest_host->h_addr_list[0]);

    /* set the socket with the input informaton */

    dest_addr.sin_family = AF_INET;
    dest_addr.sin_port	 = htons (1235);		/* XXX define 1235! */
    wdbSocket		 = RPC_ANYSOCK;

    /* set the connection timeout to the current value */

    tv.tv_sec  = netromTimeout;
    tv.tv_usec = 0;

    /*
     * set the resendCnt counter with the maximun of time the client creation
     * will be re-tried.
     */

    resendCnt = netromRetry;

    do
	{
    	/* create the backend client and connect the target deamon */
	pClnt = clntudp_create (&dest_addr, WDBPROG, WDBVERS, tv, &wdbSocket);
	}
    while ((pClnt == NULL) && (--resendCnt > 0));

    /*
     * check the client creation : If the creation failed, log a message with
     * the RPC error and return ERROR to stop the target server initialization.
     */

    if (pClnt == NULL)
	{
	wpwrLogErr ("%s", clnt_spcreateerror("netrom backend client create"));
	return (ERROR);
	}

    /* initialize the rpc core */

    rpcCoreInit (pClnt, netromTimeout, netromRetry, pTgtOps);

    /* describe the link used between the backend and the target */

    pTgtOps->tgtLink.name		= "WDB NetRom";
    pTgtOps->tgtLink.type		= TGT_LINK_ETHERNET_RPC;
    pTgtOps->tgtLink.speed		= SPEED_ETHERNET;

    pBkInfo->tgtBkVersion = BKEND_VERSION_2;    /* Backend version 2 */

    /* We give here our polling method : a selectable socket */

    pBkInfo->INFO.POLLING_METHOD.bkEndPollingMethod = POLL_SELECT_MODE;
    pBkInfo->INFO.POLLING_METHOD.BKEND_NOTIF_METHOD.pollingFd =
		    pTgtOps->tgtEventFd;

    return (OK);
    }