StdLib/BsdSocketLib/getservent.c

/*
 * Copyright (c) 1983, 1993
 *  The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *  This product includes software developed by the University of
 *  California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getservent.c    8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */

#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#ifdef YP
#include <rpc/rpc.h>
#include <rpcsvc/yp_prot.h>
#include <rpcsvc/ypclnt.h>
static int serv_stepping_yp = 0;
extern int _yp_check __P(( char ** ));
#endif


#define MAXALIASES  35

static FILE *servf = NULL;
static char line[BUFSIZ+1];
static struct servent serv;
static char *serv_aliases[MAXALIASES];
int _serv_stayopen;

#ifdef YP
char *___getservbyname_yp = NULL;
char *___getservbyproto_yp = NULL;
int ___getservbyport_yp = 0;
static char *yp_domain = NULL;

static int
_getservbyport_yp(line)
    char *line;
{
    char *result;
    int resultlen;
    char buf[YPMAXRECORD + 2];
    int rv;

    snprintf(buf, sizeof(buf), "%d/%s", ntohs(___getservbyport_yp),
                        ___getservbyproto_yp);

    ___getservbyport_yp = 0;
    ___getservbyproto_yp = NULL;

    if(!yp_domain) {
        if(yp_get_default_domain(&yp_domain))
            return (0);
    }

    /*
     * We have to be a little flexible here. Ideally you're supposed
     * to have both a services.byname and a services.byport map, but
     * some systems have only services.byname. FreeBSD cheats a little
     * by putting the services.byport information in the same map as
     * services.byname so that either case will work. We allow for both
     * possibilities here: if there is no services.byport map, we try
     * services.byname instead.
     */
    if ((rv = yp_match(yp_domain, "services.byport", buf, strlen(buf),
                        &result, &resultlen))) {
        if (rv == YPERR_MAP) {
            if (yp_match(yp_domain, "services.byname", buf,
                    strlen(buf), &result, &resultlen))
            return(0);
        } else
            return(0);
    }

    /* getservent() expects lines terminated with \n -- make it happy */
    snprintf(line, BUFSIZ, "%.*s\n", resultlen, result);

    free(result);
    return(1);
}

static int
_getservbyname_yp(line)
    char *line;
{
    char *result;
    int resultlen;
    char buf[YPMAXRECORD + 2];

    if(!yp_domain) {
        if(yp_get_default_domain(&yp_domain))
            return (0);
    }

    snprintf(buf, sizeof(buf), "%s/%s", ___getservbyname_yp,
                        ___getservbyproto_yp);

    ___getservbyname_yp = 0;
    ___getservbyproto_yp = NULL;

    if (yp_match(yp_domain, "services.byname", buf, strlen(buf),
                        &result, &resultlen)) {
        return(0);
    }

    /* getservent() expects lines terminated with \n -- make it happy */
    snprintf(line, BUFSIZ, "%.*s\n", resultlen, result);

    free(result);
    return(1);
}

static int
_getservent_yp(line)
    char *line;
{
    static char *key = NULL;
    static int keylen;
    char *lastkey, *result;
    int resultlen;
    int rv;

    if(!yp_domain) {
        if(yp_get_default_domain(&yp_domain))
            return (0);
    }

    if (!serv_stepping_yp) {
        if (key)
            free(key);
        if ((rv = yp_first(yp_domain, "services.byname", &key, &keylen,
                 &result, &resultlen))) {
            serv_stepping_yp = 0;
            return(0);
        }
        serv_stepping_yp = 1;
    } else {
        lastkey = key;
        rv = yp_next(yp_domain, "services.byname", key, keylen, &key,
                 &keylen, &result, &resultlen);
        free(lastkey);
        if (rv) {
            serv_stepping_yp = 0;
            return (0);
        }
    }

    /* getservent() expects lines terminated with \n -- make it happy */
    snprintf(line, BUFSIZ, "%.*s\n", resultlen, result);

    free(result);

    return(1);
}
#endif

void
setservent(int f)
{
    if (servf == NULL)
        servf = fopen(_PATH_SERVICES, "r" );
    else
        rewind(servf);
    _serv_stayopen |= f;
}

void
endservent()
{
    if (servf) {
        fclose(servf);
        servf = NULL;
    }
    _serv_stayopen = 0;
}

struct servent *
getservent()
{
    char *p;
    register char *cp, **q;

#ifdef YP
    if (serv_stepping_yp && _getservent_yp(line)) {
        p = (char *)&line;
        goto unpack;
    }
tryagain:
#endif
    if (servf == NULL && (servf = fopen(_PATH_SERVICES, "r" )) == NULL)
        return (NULL);
again:
    if ((p = fgets(line, BUFSIZ, servf)) == NULL)
        return (NULL);
#ifdef YP
    if (*p == '+' && _yp_check(NULL)) {
        if (___getservbyname_yp != NULL) {
            if (!_getservbyname_yp(line))
                goto tryagain;
        }
        else if (___getservbyport_yp != 0) {
            if (!_getservbyport_yp(line))
                goto tryagain;
        }
        else if (!_getservent_yp(line))
            goto tryagain;
    }
unpack:
#endif
    if (*p == '#')
        goto again;
    cp = strpbrk(p, "#\n");
    if (cp == NULL)
        goto again;
    *cp = '\0';
    serv.s_name = p;
    p = strpbrk(p, " \t");
    if (p == NULL)
        goto again;
    *p++ = '\0';
    while (*p == ' ' || *p == '\t')
        p++;
    cp = strpbrk(p, ",/");
    if (cp == NULL)
        goto again;
    *cp++ = '\0';
    serv.s_port = htons((u_short)atoi(p));
    serv.s_proto = cp;
    q = serv.s_aliases = serv_aliases;
    cp = strpbrk(cp, " \t");
    if (cp != NULL)
        *cp++ = '\0';
    while (cp && *cp) {
        if (*cp == ' ' || *cp == '\t') {
            cp++;
            continue;
        }
        if (q < &serv_aliases[MAXALIASES - 1])
            *q++ = cp;
        cp = strpbrk(cp, " \t");
        if (cp != NULL)
            *cp++ = '\0';
    }
    *q = NULL;
    return (&serv);
}