/*      $NetBSD: sethostent.c,v 1.20 2014/03/17 13:24:23 christos Exp $ */

/*
 * Copyright (c) 1985, 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. 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.
 */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)sethostent.c        8.1 (Berkeley) 6/4/93";
static char rcsid[] = "Id: sethostent.c,v 8.5 1996/09/28 06:51:07 vixie Exp ";
#else
__RCSID("$NetBSD: sethostent.c,v 1.20 2014/03/17 13:24:23 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */

#include "namespace.h"
#include <sys/param.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <assert.h>
#include <string.h>
#include <nsswitch.h>
#include <netdb.h>
#include <resolv.h>
#include <errno.h>
#include <stdlib.h>

#include "hostent.h"

#ifdef __HAIKU__
#include <libutil.h>
#include <FindDirectory.h>
#endif

#ifdef __weak_alias
__weak_alias(sethostent,_sethostent)
__weak_alias(endhostent,_endhostent)
#endif

#ifndef _REENTRANT
void    res_close(void);
#endif

static struct hostent *_hf_gethtbyname2(const char *, int, struct getnamaddr *);

void
/*ARGSUSED*/
sethostent(int stayopen)
{
#ifndef _REENTRANT
        if ((_res.options & RES_INIT) == 0 && res_init() == -1)
                return;
        if (stayopen)
                _res.options |= RES_STAYOPEN | RES_USEVC;
#endif
        sethostent_r(&_h_file);
}

void
endhostent(void)
{
#ifndef _REENTRANT
        _res.options &= ~(RES_STAYOPEN | RES_USEVC);
        res_close();
#endif
        endhostent_r(&_h_file);
}

void
sethostent_r(FILE **hf)
{
        if (!*hf) {
#ifdef __HAIKU__
                char buffer[256];
                find_directory(B_SYSTEM_SETTINGS_DIRECTORY, 0, false,
                        buffer, sizeof(buffer));
                strlcat(buffer, "/network/hosts", sizeof(buffer));
                *hf = fopen(buffer, "re");
#else
                *hf = fopen(_h_hosts, "re");
#endif
        } else
                rewind(*hf);
}

void
endhostent_r(FILE **hf)
{
        if (*hf) {
                (void)fclose(*hf);
                *hf = NULL;
        }
}

/*ARGSUSED*/
int
_hf_gethtbyname(void *rv, void *cb_data, va_list ap)
{
        struct hostent *hp;
        const char *name;
        int af;
        struct getnamaddr *info = rv;

        _DIAGASSERT(rv != NULL);

        name = va_arg(ap, char *);
        /* NOSTRICT skip string len */(void)va_arg(ap, int);
        af = va_arg(ap, int);

#if 0
        {
                res_state res = __res_get_state();
                if (res == NULL)
                        return NS_NOTFOUND;
                if (res->options & RES_USE_INET6)
                        hp = _hf_gethtbyname2(name, AF_INET6, info);
                else
                        hp = NULL;
                if (hp == NULL)
                        hp = _hf_gethtbyname2(name, AF_INET, info);
                __res_put_state(res);
        }
#else
        hp = _hf_gethtbyname2(name, af, info);
#endif
        if (hp == NULL) {
                *info->he = HOST_NOT_FOUND;
                return NS_NOTFOUND;
        }
        return NS_SUCCESS;
}

struct hostent *
_hf_gethtbyname2(const char *name, int af, struct getnamaddr *info)
{
        struct hostent *hp, hent;
        char *buf, *ptr;
        size_t len, anum, num, i;
        FILE *hf;
        char *aliases[MAXALIASES];
        char *addr_ptrs[MAXADDRS];

        _DIAGASSERT(name != NULL);

        hf = NULL;
        sethostent_r(&hf);
        if (hf == NULL) {
                errno = EINVAL;
                *info->he = NETDB_INTERNAL;
                return NULL;
        }

        if ((ptr = buf = malloc(len = info->buflen)) == NULL) {
                *info->he = NETDB_INTERNAL;
                return NULL;
        }

        anum = 0;               /* XXX: gcc */
        hent.h_name = NULL;     /* XXX: gcc */
        hent.h_addrtype = 0;    /* XXX: gcc */
        hent.h_length = 0;      /* XXX: gcc */

        for (num = 0; num < MAXADDRS;) {
                info->hp->h_addrtype = af;
                info->hp->h_length = 0;

                hp = gethostent_r(hf, info->hp, info->buf, info->buflen,
                    info->he);
                if (hp == NULL)
                        break;

                if (strcasecmp(hp->h_name, name) != 0) {
                        char **cp;
                        for (cp = hp->h_aliases; *cp != NULL; cp++)
                                if (strcasecmp(*cp, name) == 0)
                                        break;
                        if (*cp == NULL) continue;
                }

                if (num == 0) {
                        hent.h_addrtype = af = hp->h_addrtype;
                        hent.h_length = hp->h_length;

                        HENT_SCOPY(hent.h_name, hp->h_name, ptr, len);
                        for (anum = 0; hp->h_aliases[anum]; anum++) {
                                if (anum >= __arraycount(aliases))
                                        goto nospc;
                                HENT_SCOPY(aliases[anum], hp->h_aliases[anum],
                                    ptr, len);
                        }
                        ptr = (void *)ALIGN(ptr);
                        if ((size_t)(ptr - buf) >= info->buflen)
                                goto nospc;
                }

                if (num >= __arraycount(addr_ptrs))
                        goto nospc;
                HENT_COPY(addr_ptrs[num], hp->h_addr_list[0], hp->h_length, ptr,
                    len);
                num++;
        }
        endhostent_r(&hf);

        if (num == 0) {
                *info->he = HOST_NOT_FOUND;
                free(buf);
                return NULL;
        }

        hp = info->hp;
        ptr = info->buf;
        len = info->buflen;

        hp->h_addrtype = hent.h_addrtype;
        hp->h_length = hent.h_length;

        HENT_ARRAY(hp->h_aliases, anum, ptr, len);
        HENT_ARRAY(hp->h_addr_list, num, ptr, len);

        for (i = 0; i < num; i++)
                HENT_COPY(hp->h_addr_list[i], addr_ptrs[i], hp->h_length, ptr,
                    len);
        hp->h_addr_list[num] = NULL;

        HENT_SCOPY(hp->h_name, hent.h_name, ptr, len);

        for (i = 0; i < anum; i++)
                HENT_SCOPY(hp->h_aliases[i], aliases[i], ptr, len);
        hp->h_aliases[anum] = NULL;

        free(buf);
        return hp;
nospc:
        *info->he = NETDB_INTERNAL;
        free(buf);
        errno = ENOSPC;
        return NULL;
}

/*ARGSUSED*/
int
_hf_gethtbyaddr(void *rv, void *cb_data, va_list ap)
{
        struct hostent *hp;
        const unsigned char *addr;
        struct getnamaddr *info = rv;
        FILE *hf;

        _DIAGASSERT(rv != NULL);

        addr = va_arg(ap, unsigned char *);
        info->hp->h_length = va_arg(ap, int);
        info->hp->h_addrtype = va_arg(ap, int);
        
        hf = NULL;
        sethostent_r(&hf);
        if (hf == NULL) {
                *info->he = NETDB_INTERNAL;
                return NS_UNAVAIL;
        }
        while ((hp = gethostent_r(hf, info->hp, info->buf, info->buflen,
            info->he)) != NULL)
                if (!memcmp(hp->h_addr_list[0], addr, (size_t)hp->h_length))
                        break;
        endhostent_r(&hf);

        if (hp == NULL) {
                *info->he = HOST_NOT_FOUND;
                return NS_NOTFOUND;
        }
        return NS_SUCCESS;
}