multiskt.c

项目描述: slsnif is a serial port logging utility. It listens to the specified serial port and logs all

/* multiskt.c: this program can open up multiple accepts on one server */
#include <stdio.h>
#include "xtdio.h"
#include "sockets.h"

/* ----------------------------------------------------------------------
 * Definitions:
 */
#define BUFSIZE 128

/* ----------------------------------------------------------------------
 * Typedefs:
 */
typedef struct sktlist_str SktList;


/* ----------------------------------------------------------------------
 * Data Structures:
 */
struct sktlist_str {
    int      id;
    Socket  *skt;
    SktList *nxt,*prv;
    };

/* ----------------------------------------------------------------------
 * Global Data:
 */
Socket  *srvr = NULL;
SktList *shd  = NULL;
SktList *stl  = NULL;

/* ---------------------------------------------------------------------- */

/* main: */
#ifdef __PROTOTYPE__
int main(
  int argc,
  char **argv)
#else	/* __PROTOTYPE__ */
int main(argc,argv)
int argc;
char **argv;
#endif	/* __PROTOTYPE__ */
{
char     mesg[BUFSIZE];
Socket  *skt        = NULL;
SktList *sktlist    = NULL;
SktList *sktlistnxt = NULL;

rdcolor();

/* open server */
srvr= Sopen("multiskt","s");
if(!srvr) {
    /* if "multiskt" did not open, this code (rudely) attempts to remove
     * any servers by that name and then re-open
     */
    Srmsrvr("multiskt");
    srvr= Sopen("multiskt","s");
    if(!srvr) error(XTDIO_ERROR,"unable to open <multiskt> as server\n");
    }

/* ok, read stuff into skt messages (so long as there are clients) */
Smaskset(srvr);
do {

	/* block until a Socket needs service */
    Smaskwait();

	/* if client awaiting connection, go ahead and connect to it */
    if(Stest(srvr)) {
        skt= Saccept(srvr);
        if(!skt) {
            error(XTDIO_WARNING,"unable to accept\n");
            continue;
            }

        /* allocate a doubly-linked SktList */
        sktlist= (SktList *) malloc(sizeof(SktList));
        if(stl) stl->nxt= sktlist;
        else    shd     = sktlist;
        sktlist->prv= stl;
        sktlist->nxt= NULL;
		stl         = sktlist;

        /* initialize the SktList */
        sktlist->id = stl->prv? (stl->prv->id + 1) : 1;
        sktlist->skt= skt;

        /* set up Smaskwait mask -- all Sockets entered into this mask will
		 * be waited upon as a group
		 */
        Smaskset(sktlist->skt);
        }

    else {    /* process communication from a client */
        sktlistnxt= NULL;

		/* scan all clients loop */
        for(sktlist= shd; sktlist; sktlist= sktlistnxt) {
            sktlistnxt= sktlist->nxt;

			/* is something waiting on this Socket? */
            if(Stest(sktlist->skt)) {

				/* something waiting on this Socket, get it */
                Sgets(mesg,BUFSIZE,sktlist->skt);

				/* report on message */
                printf("skt%d: mesg<%s>\n",sktlist->id,mesg);

				/* send message back */
                Sprintf(sktlist->skt,"received <%s>\n",sprt(mesg));

				/* sktlist is quitting on receipt of q */
                if(!strcmp(mesg,"q")) {

					/* close down Socket */
                    Sclose(sktlist->skt);
					Smaskunset(sktlist->skt);

					/* remove sktlist entry from linked list */
                    if(sktlist->prv) sktlist->prv->nxt= sktlist->nxt;
                    else             shd              = sktlist->nxt;
                    if(sktlist->nxt) sktlist->nxt->prv= sktlist->prv;
                    else             stl              = sktlist->prv;

					/* free up former sktlist memory */
                    free((char *) sktlist);
                    }    /* quit                             */
                }        /* get a message from a client      */
            }            /* sktlist loop                     */
        }                /* client communications processing */
    } while(shd);

/* close down the server */
Sclose(srvr);
return 0;
}

/* ---------------------------------------------------------------------- */