/*
 * Copyright (c) 1989, 1993, 1995
 *      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.
 */

/*
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "port_before.h"

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>

#ifdef IRS_LCL_SV_DB
#include <db.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include <irs.h>
#include <isc/memcluster.h>

#include "port_after.h"

#include "irs_p.h"
#include "lcl_p.h"

#ifdef SPRINTF_CHAR
# define SPRINTF(x) strlen(sprintf/**/x)
#else
# define SPRINTF(x) ((size_t)sprintf x)
#endif

/* Types */

struct pvt {
#ifdef IRS_LCL_SV_DB
        DB *            dbh;
        int             dbf;
#endif
        struct lcl_sv   sv;
};

/* Forward */

static void                     sv_close(struct irs_sv*);
static struct servent *         sv_next(struct irs_sv *);
static struct servent *         sv_byname(struct irs_sv *, const char *,
                                          const char *);
static struct servent *         sv_byport(struct irs_sv *, int, const char *);
static void                     sv_rewind(struct irs_sv *);
static void                     sv_minimize(struct irs_sv *);
/*global*/ struct servent *     irs_lclsv_fnxt(struct lcl_sv *);
#ifdef IRS_LCL_SV_DB
static struct servent *         sv_db_rec(struct lcl_sv *, DBT *, DBT *);
#endif

/* Portability */

#ifndef SEEK_SET
# define SEEK_SET 0
#endif

/* Public */

struct irs_sv *
irs_lcl_sv(struct irs_acc *this) {
        struct irs_sv *sv;
        struct pvt *pvt;

        UNUSED(this);

        if ((sv = memget(sizeof *sv)) == NULL) {
                errno = ENOMEM;
                return (NULL);
        }
        memset(sv, 0x5e, sizeof *sv);
        if ((pvt = memget(sizeof *pvt)) == NULL) {
                memput(sv, sizeof *sv);
                errno = ENOMEM;
                return (NULL);
        }
        memset(pvt, 0, sizeof *pvt);
        sv->private = pvt;
        sv->close = sv_close;
        sv->next = sv_next;
        sv->byname = sv_byname;
        sv->byport = sv_byport;
        sv->rewind = sv_rewind;
        sv->minimize = sv_minimize;
        sv->res_get = NULL;
        sv->res_set = NULL;
#ifdef IRS_LCL_SV_DB
        pvt->dbf = R_FIRST;
#endif
        return (sv);
}

/* Methods */

static void
sv_close(struct irs_sv *this) {
        struct pvt *pvt = (struct pvt *)this->private;

#ifdef IRS_LCL_SV_DB
        if (pvt->dbh != NULL)
                (*pvt->dbh->close)(pvt->dbh);
#endif
        if (pvt->sv.fp)
                fclose(pvt->sv.fp);
        memput(pvt, sizeof *pvt);
        memput(this, sizeof *this);
}

static struct servent *
sv_byname(struct irs_sv *this, const char *name, const char *proto) {
#ifdef IRS_LCL_SV_DB
        struct pvt *pvt = (struct pvt *)this->private;
#endif
        struct servent *p;
        char **cp;

        sv_rewind(this);
#ifdef IRS_LCL_SV_DB
        if (pvt->dbh != NULL) {
                DBT key, data;

                /* Note that (sizeof "/") == 2. */
                if ((strlen(name) + sizeof "/" + proto ? strlen(proto) : 0)
                    > sizeof pvt->sv.line)
                        goto try_local;
                key.data = pvt->sv.line;
                key.size = SPRINTF((pvt->sv.line, "%s/%s", name,
                                    proto ? proto : "")) + 1;
                if (proto != NULL) {
                        if ((*pvt->dbh->get)(pvt->dbh, &key, &data, 0) != 0)
                                return (NULL);
                } else if ((*pvt->dbh->seq)(pvt->dbh, &key, &data, R_CURSOR)
                           != 0)
                        return (NULL);
                return (sv_db_rec(&pvt->sv, &key, &data));
        }
 try_local:
#endif

        while ((p = sv_next(this))) {
                if (strcmp(name, p->s_name) == 0)
                        goto gotname;
                for (cp = p->s_aliases; *cp; cp++)
                        if (strcmp(name, *cp) == 0)
                                goto gotname;
                continue;
 gotname:
                if (proto == NULL || strcmp(p->s_proto, proto) == 0)
                        break;
        }
        return (p);
}

static struct servent *
sv_byport(struct irs_sv *this, int port, const char *proto) {
#ifdef IRS_LCL_SV_DB
        struct pvt *pvt = (struct pvt *)this->private;
#endif
        struct servent *p;

        sv_rewind(this);
#ifdef IRS_LCL_SV_DB
        if (pvt->dbh != NULL) {
                DBT key, data;
                u_short *ports;

                ports = (u_short *)pvt->sv.line;
                ports[0] = 0;
                ports[1] = port;
                key.data = ports;
                key.size = sizeof(u_short) * 2;
                if (proto && *proto) {
                        strncpy((char *)ports + key.size, proto,
                                BUFSIZ - key.size);
                        key.size += strlen((char *)ports + key.size) + 1;
                        if ((*pvt->dbh->get)(pvt->dbh, &key, &data, 0) != 0)
                                return (NULL);
                } else {
                        if ((*pvt->dbh->seq)(pvt->dbh, &key, &data, R_CURSOR)
                            != 0)
                                return (NULL);
                }
                return (sv_db_rec(&pvt->sv, &key, &data));
        }
#endif
        while ((p = sv_next(this))) {
                if (p->s_port != port)
                        continue;
                if (proto == NULL || strcmp(p->s_proto, proto) == 0)
                        break;
        }
        return (p);
}

static void
sv_rewind(struct irs_sv *this) {
        struct pvt *pvt = (struct pvt *)this->private;

        if (pvt->sv.fp) {
                if (fseek(pvt->sv.fp, 0L, SEEK_SET) == 0)
                        return;
                (void)fclose(pvt->sv.fp);
                pvt->sv.fp = NULL;
        }
#ifdef IRS_LCL_SV_DB
        pvt->dbf = R_FIRST;
        if (pvt->dbh != NULL)
                return;
        pvt->dbh = dbopen(_PATH_SERVICES_DB, O_RDONLY,O_RDONLY,DB_BTREE, NULL);
        if (pvt->dbh != NULL) {
                if (fcntl((*pvt->dbh->fd)(pvt->dbh), F_SETFD, 1) < 0) {
                        (*pvt->dbh->close)(pvt->dbh);
                        pvt->dbh = NULL;
                }
                return;
        }
#endif
        if ((pvt->sv.fp = fopen(_PATH_SERVICES, "r")) == NULL)
                return;
        if (fcntl(fileno(pvt->sv.fp), F_SETFD, 1) < 0) {
                (void)fclose(pvt->sv.fp);
                pvt->sv.fp = NULL;
        }
}

static struct servent *
sv_next(struct irs_sv *this) {
        struct pvt *pvt = (struct pvt *)this->private;

#ifdef IRS_LCL_SV_DB
        if (pvt->dbh == NULL && pvt->sv.fp == NULL)
#else
        if (pvt->sv.fp == NULL)
#endif
                sv_rewind(this);

#ifdef IRS_LCL_SV_DB
        if (pvt->dbh != NULL) {
                DBT key, data;

                while ((*pvt->dbh->seq)(pvt->dbh, &key, &data, pvt->dbf) == 0){
                        pvt->dbf = R_NEXT;
                        if (((char *)key.data)[0])
                                continue;
                        return (sv_db_rec(&pvt->sv, &key, &data));
                }
        }
#endif

        if (pvt->sv.fp == NULL)
                return (NULL);
        return (irs_lclsv_fnxt(&pvt->sv));
}

static void
sv_minimize(struct irs_sv *this) {
        struct pvt *pvt = (struct pvt *)this->private;

#ifdef IRS_LCL_SV_DB
        if (pvt->dbh != NULL) {
                (*pvt->dbh->close)(pvt->dbh);
                pvt->dbh = NULL;
        }
#endif
        if (pvt->sv.fp != NULL) {
                (void)fclose(pvt->sv.fp);
                pvt->sv.fp = NULL;
        }
}

/* Quasipublic. */

struct servent *
irs_lclsv_fnxt(struct lcl_sv *sv) {
        char *p, *cp, **q;

 again:
        if ((p = fgets(sv->line, BUFSIZ, sv->fp)) == NULL)
                return (NULL);
        if (*p == '#')
                goto again;
        sv->serv.s_name = p;
        while (*p && *p != '\n' && *p != ' ' && *p != '\t' && *p != '#')
                ++p;
        if (*p == '\0' || *p == '#' || *p == '\n')
                goto again;
        *p++ = '\0';
        while (*p == ' ' || *p == '\t')
                p++;
        if (*p == '\0' || *p == '#' || *p == '\n')
                goto again;
        sv->serv.s_port = htons((u_short)strtol(p, &cp, 10));
        if (cp == p || (*cp != '/' && *cp != ','))
                goto again;
        p = cp + 1;
        sv->serv.s_proto = p;

        q = sv->serv.s_aliases = sv->serv_aliases;

        while (*p && *p != '\n' && *p != ' ' && *p != '\t' && *p != '#')
                ++p;

        while (*p == ' ' || *p == '\t') {
                *p++ = '\0';
                while (*p == ' ' || *p == '\t')
                        ++p;
                if (*p == '\0' || *p == '#' || *p == '\n')
                        break;
                if (q < &sv->serv_aliases[IRS_SV_MAXALIASES - 1])
                        *q++ = p;
                while (*p && *p != '\n' && *p != ' ' && *p != '\t' && *p != '#')
                        ++p;
        }

        *p = '\0';
        *q = NULL;
        return (&sv->serv);
}

/* Private. */

#ifdef IRS_LCL_SV_DB
static struct servent *
sv_db_rec(struct lcl_sv *sv, DBT *key, DBT *data) {
        char *p, **q;
        int n;

        p = data->data;
        p[data->size - 1] = '\0';       /*%< should be, but we depend on it */
        if (((char *)key->data)[0] == '\0') {
                if (key->size < sizeof(u_short)*2 || data->size < 2)
                        return (NULL);
                sv->serv.s_port = ((u_short *)key->data)[1];
                n = strlen(p) + 1;
                if ((size_t)n > sizeof(sv->line)) {
                        n = sizeof(sv->line);
                }
                memcpy(sv->line, p, n);
                sv->serv.s_name = sv->line;
                if ((sv->serv.s_proto = strchr(sv->line, '/')) != NULL)
                        *(sv->serv.s_proto)++ = '\0';
                p += n;
                data->size -= n;
        } else {
                if (data->size < sizeof(u_short) + 1)
                        return (NULL);
                if (key->size > sizeof(sv->line))
                        key->size = sizeof(sv->line);
                ((char *)key->data)[key->size - 1] = '\0';
                memcpy(sv->line, key->data, key->size);
                sv->serv.s_name = sv->line;
                if ((sv->serv.s_proto = strchr(sv->line, '/')) != NULL)
                        *(sv->serv.s_proto)++ = '\0';
                sv->serv.s_port = *(u_short *)data->data;
                p += sizeof(u_short);
                data->size -= sizeof(u_short);
        }
        q = sv->serv.s_aliases = sv->serv_aliases;
        while (data->size > 0 && q < &sv->serv_aliases[IRS_SV_MAXALIASES - 1]) {

                *q++ = p;
                n = strlen(p) + 1;
                data->size -= n;
                p += n;
        }
        *q = NULL;
        return (&sv->serv);
}
#endif

/*! \file */