usr.lib/in.chargend/in.chargend.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * chargen inetd service - both stream and dgram based.
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdio.h>
#include <strings.h>
#include <netinet/in.h>
#include <sys/sysmacros.h>
#include <ctype.h>
#include <inetsvc.h>


#define LINESIZE        72
#define RINGSIZE        128


static  char    ring[RINGSIZE];
static  char    *endring;


static void
initring(void)
{
    unsigned char ch;

    endring = ring;

    for (ch = 0; ch <= RINGSIZE; ++ch) {
        if (isprint(ch))
            *endring++ = ch;
    }
}

static void
chargen_stream(int s, char *argv[])
{
    char    text[LINESIZE+2];
    int i;
    char    *rp;
    char    *dp;
    char    *rs = ring;

    setproctitle("chargen", s, argv);

    for (;;) {
        if (rs >= endring)
            rs = ring;
        rp = rs++;
        dp = text;
        i = MIN(LINESIZE, endring - rp);
        (void) memmove(dp, rp, i);
        dp += i;
        if ((rp += i) >= endring)
            rp = ring;
        if (i < LINESIZE) {
            i = LINESIZE - i;
            (void) memmove(dp, rp, i);
            dp += i;
            if ((rp += i) >= endring)
                rp = ring;
        }

        *dp++ = '\r';
        *dp++ = '\n';

        if (safe_write(s, text, dp - text) != 0)
            break;
    }
}

/* ARGSUSED3 */
static void
chargen_dg(int s, const struct sockaddr *sap, int sa_size, const void *buf,
    size_t sz)
{
    char        text[LINESIZE+2];
    int     i;
    char        *rp;
    static char     *rs = ring;

    rp = rs;
    if (rs++ >= endring)
        rs = ring;
    i = MIN(LINESIZE, endring - rp);
    (void) memmove(text, rp, i);
    if ((rp += i) >= endring)
        rp = ring;
    if (i < LINESIZE) {
        (void) memmove(text, rp, i);
        if ((rp += i) >= endring)
            rp = ring;
    }

    text[LINESIZE - 2] = '\r';
    text[LINESIZE - 1] = '\n';

    (void) safe_sendto(s, text, sizeof (text), 0, sap, sa_size);
}

int
main(int argc, char *argv[])
{
    opterr = 0; /* disable getopt error msgs */

    initring();

    switch (getopt(argc, argv, "ds")) {
    case 'd':
        dg_template(chargen_dg, STDIN_FILENO, NULL, 0);
        break;
    case 's':
        chargen_stream(STDIN_FILENO, argv);
        break;
    default:
        return (1);
    }

    return (0);
}