/*      $OpenBSD: getrpcent.c,v 1.22 2020/10/13 04:42:28 guenther Exp $ */

/*
 * Copyright (c) 2010, Oracle America, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of the "Oracle America, Inc." 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 COPYRIGHT HOLDERS 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
 *   COPYRIGHT HOLDER 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.
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <string.h>
#include <limits.h>
#include <rpc/rpc.h>

/*
 * Internet version.
 */
static struct rpcdata {
        FILE    *rpcf;
        int     stayopen;
#define MAXALIASES      35
        char    *rpc_aliases[MAXALIASES];
        struct  rpcent rpc;
        char    line[BUFSIZ+1];
} *rpcdata;

static  struct rpcent *interpret(char *val, int len);

static const char RPCDB[] = "/etc/rpc";

static struct rpcdata *
_rpcdata(void)
{
        struct rpcdata *d = rpcdata;

        if (d == NULL) {
                d = calloc(1, sizeof (struct rpcdata));
                rpcdata = d;
        }
        return (d);
}

struct rpcent *
getrpcbynumber(int number)
{
        struct rpcdata *d = _rpcdata();
        struct rpcent *p;

        if (d == NULL)
                return (0);
        setrpcent(0);
        while ((p = getrpcent())) {
                if (p->r_number == number)
                        break;
        }
        endrpcent();
        return (p);
}

struct rpcent *
getrpcbyname(char *name)
{
        struct rpcent *rpc;
        char **rp;

        setrpcent(0);
        while ((rpc = getrpcent())) {
                if (strcmp(rpc->r_name, name) == 0)
                        goto done;
                for (rp = rpc->r_aliases; *rp != NULL; rp++) {
                        if (strcmp(*rp, name) == 0)
                                goto done;
                }
        }
done:
        endrpcent();
        return (rpc);
}

void
setrpcent(int f)
{
        struct rpcdata *d = _rpcdata();

        if (d == NULL)
                return;
        if (d->rpcf == NULL)
                d->rpcf = fopen(RPCDB, "re");
        else
                rewind(d->rpcf);
        d->stayopen |= f;
}
DEF_WEAK(setrpcent);

void
endrpcent(void)
{
        struct rpcdata *d = _rpcdata();

        if (d == NULL)
                return;
        if (d->rpcf && !d->stayopen) {
                fclose(d->rpcf);
                d->rpcf = NULL;
        }
}
DEF_WEAK(endrpcent);

struct rpcent *
getrpcent(void)
{
        struct rpcdata *d = _rpcdata();

        if (d == NULL)
                return(NULL);
        if (d->rpcf == NULL && (d->rpcf = fopen(RPCDB, "re")) == NULL)
                return (NULL);
        /* -1 so there is room to append a \n below */
        if (fgets(d->line, sizeof(d->line) - 1, d->rpcf) == NULL)
                return (NULL);
        return (interpret(d->line, strlen(d->line)));
}
DEF_WEAK(getrpcent);

static struct rpcent *
interpret(char *val, int len)
{
        const char *errstr;
        struct rpcdata *d = _rpcdata();
        char *p;
        char *cp, *num, **q;

        if (d == NULL)
                return (0);
        strlcpy(d->line, val, sizeof(d->line));
        p = d->line;
        p[len] = '\n';
        if (*p == '#')
                return (getrpcent());
        cp = strpbrk(p, "#\n");
        if (cp == NULL)
                return (getrpcent());
        *cp = '\0';
        cp = strpbrk(p, " \t");
        if (cp == NULL)
                return (getrpcent());
        *cp++ = '\0';
        /* THIS STUFF IS INTERNET SPECIFIC */
        d->rpc.r_name = d->line;
        while (*cp == ' ' || *cp == '\t')
                cp++;
        num = cp;
        cp = strpbrk(cp, " \t");
        if (cp != NULL)
                *cp++ = '\0';
        d->rpc.r_number = strtonum(num, 0, INT_MAX, &errstr);
        if (errstr)
                return (0);
        q = d->rpc.r_aliases = d->rpc_aliases;
        while (cp && *cp) {
                if (*cp == ' ' || *cp == '\t') {
                        cp++;
                        continue;
                }
                if (q < &(d->rpc_aliases[MAXALIASES - 1]))
                        *q++ = cp;
                cp = strpbrk(cp, " \t");
                if (cp != NULL)
                        *cp++ = '\0';
        }
        *q = NULL;
        return (&d->rpc);
}