/*      $NetBSD: services_mkdb.c,v 1.14 2008/04/28 20:24:17 martin Exp $        */

/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 1999 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Luke Mewburn and Christos Zoulas.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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/param.h>
#include <sys/stat.h>

#include <assert.h>
#include <db.h>
#include <err.h>
#include <fcntl.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <libgen.h>
#include <ctype.h>
#include <errno.h>
#include <stringlist.h>

#include "extern.h"

static char tname[MAXPATHLEN];

#define PMASK           0xffff
#define PROTOMAX        6

static void     add(DB *, StringList *, size_t, const char *, size_t *, int);
static StringList ***parseservices(const char *, StringList *);
static void     cleanup(void);
static void     store(DB *, DBT *, DBT *, int);
static void     killproto(DBT *);
static char    *getstring(const char *, size_t, char **, const char *);
static size_t   getprotoindex(StringList *, const char *);
static const char *getprotostr(StringList *, size_t);
static const char *mkaliases(StringList *, char *, size_t);
static void     usage(void);

HASHINFO hinfo = {
        .bsize = 256,
        .ffactor = 4,
        .nelem = 32768,
        .cachesize = 1024,
        .hash = NULL,
        .lorder = 0
};


int
main(int argc, char *argv[])
{
        DB      *db;
        int      ch;
        const char *fname = _PATH_SERVICES;
        const char *dbname = _PATH_SERVICES_DB;
        int      warndup = 1;
        int      unique = 0;
        int      otherflag = 0;
        int      byteorder = 0;
        size_t   cnt = 0;
        StringList *sl, ***svc;
        size_t port, proto;
        char *dbname_dir, *dbname_dirbuf;
        int dbname_dir_fd = -1;

        setprogname(argv[0]);

        while ((ch = getopt(argc, argv, "blo:qu")) != -1)
                switch (ch) {
                case 'b':
                case 'l':
                        if (byteorder != 0)
                                usage();
                        byteorder = ch == 'b' ? 4321 : 1234;
                        break;
                case 'q':
                        otherflag = 1;
                        warndup = 0;
                        break;
                case 'o':
                        otherflag = 1;
                        dbname = optarg;
                        break;
                case 'u':
                        unique++;
                        break;
                case '?':
                default:
                        usage();
                }

        argc -= optind;
        argv += optind;

        if (argc > 1 || (unique && otherflag))
                usage();
        if (argc == 1)
                fname = argv[0];

        /* Set byte order. */
        hinfo.lorder = byteorder;

        if (unique)
                uniq(fname);

        svc = parseservices(fname, sl = sl_init());

        if (atexit(cleanup))
                err(1, "Cannot install exit handler");

        (void)snprintf(tname, sizeof(tname), "%s.tmp", dbname);
        db = dbopen(tname, O_RDWR | O_CREAT | O_EXCL,
            (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH), DB_HASH, &hinfo);
        if (!db)
                err(1, "Error opening temporary database `%s'", tname);


        for (port = 0; port < PMASK + 1; port++) {
                if (svc[port] == NULL)
                        continue;

                for (proto = 0; proto < PROTOMAX; proto++) {
                        StringList *s;
                        if ((s = svc[port][proto]) == NULL)
                                continue;
                        add(db, s, port, getprotostr(sl, proto), &cnt, warndup);
                }

                free(svc[port]);
        }

        free(svc);
        sl_free(sl, 1);

        if ((db->close)(db))
                err(1, "Error closing temporary database `%s'", tname);

        /*
         * Make sure file is safe on disk. To improve performance we will call
         * fsync() to the directory where file lies
         */
        if (rename(tname, dbname) == -1 ||
            (dbname_dirbuf = strdup(dbname)) == NULL ||
            (dbname_dir = dirname(dbname_dirbuf)) == NULL ||
            (dbname_dir_fd = open(dbname_dir, O_RDONLY|O_DIRECTORY)) == -1 ||
            fsync(dbname_dir_fd) != 0) {
                if (dbname_dir_fd != -1)
                        close(dbname_dir_fd);
                err(1, "Cannot rename `%s' to `%s'", tname, dbname);
        }

        if (dbname_dir_fd != -1)
                close(dbname_dir_fd);

        return 0;
}

static void
add(DB *db, StringList *sl, size_t port, const char *proto, size_t *cnt,
    int warndup)
{
        size_t i;
        char     keyb[BUFSIZ], datab[BUFSIZ], abuf[BUFSIZ];
        DBT      data, key;
        key.data = keyb;
        data.data = datab;

#ifdef DEBUG
        (void)printf("add %s %zu %s [ ", sl->sl_str[0], port, proto);
        for (i = 1; i < sl->sl_cur; i++)
            (void)printf("%s ", sl->sl_str[i]);
        (void)printf("]\n");
#endif

        /* key `indirect key', data `full line' */
        data.size = snprintf(datab, sizeof(datab), "%zu", (*cnt)++) + 1;
        key.size = snprintf(keyb, sizeof(keyb), "%s %zu/%s %s",
            sl->sl_str[0], port, proto, mkaliases(sl, abuf, sizeof(abuf))) + 1;
        store(db, &data, &key, warndup);

        /* key `\377port/proto', data = `indirect key' */
        key.size = snprintf(keyb, sizeof(keyb), "\377%zu/%s",
            port, proto) + 1;
        store(db, &key, &data, warndup);

        /* key `\377port', data = `indirect key' */
        killproto(&key);
        store(db, &key, &data, warndup);

        /* add references for service and all aliases */
        for (i = 0; i < sl->sl_cur; i++) {
                /* key `\376service/proto', data = `indirect key' */
                key.size = snprintf(keyb, sizeof(keyb), "\376%s/%s",
                    sl->sl_str[i], proto) + 1;
                store(db, &key, &data, warndup);

                /* key `\376service', data = `indirect key' */
                killproto(&key);
                store(db, &key, &data, warndup);
        }
        sl_free(sl, 1);
}

static StringList ***
parseservices(const char *fname, StringList *sl)
{
        ssize_t len;
        size_t linecap, line, pindex;
        FILE *fp;
        StringList ***svc, *s;
        char *p, *ep;

        if ((fp = fopen(fname, "r")) == NULL)
                err(1, "Cannot open `%s'", fname);

        line = linecap = 0;
        if ((svc = calloc(PMASK + 1, sizeof(StringList **))) == NULL)
                err(1, "Cannot allocate %zu bytes", (size_t)(PMASK + 1));

        p = NULL;
        while ((len = getline(&p, &linecap, fp)) != -1) {
                char    *name, *port, *proto, *aliases, *cp, *alias;
                unsigned long pnum;

                line++;

                if (len == 0)
                        continue;

                if (p[len - 1] == '\n')
                        p[len - 1] = '\0';

                for (cp = p; *cp && isspace((unsigned char)*cp); cp++)
                        continue;

                if (*cp == '\0' || *cp == '#')
                        continue;

                if ((name = getstring(fname, line, &cp, "name")) == NULL)
                        continue;

                if ((port = getstring(fname, line, &cp, "port")) == NULL)
                        continue;

                if (cp) {
                        for (aliases = cp; *cp && *cp != '#'; cp++)
                                continue;

                        if (*cp)
                                *cp = '\0';
                } else
                        aliases = NULL;

                proto = strchr(port, '/');
                if (proto == NULL || proto[1] == '\0') {
                        warnx("%s, %zu: no protocol found", fname, line);
                        continue;
                }
                *proto++ = '\0';

                errno = 0;
                pnum = strtoul(port, &ep, 0);
                if (*port == '\0' || *ep != '\0') {
                        warnx("%s, %zu: invalid port `%s'", fname, line, port);
                        continue;
                }
                if ((errno == ERANGE && pnum == ULONG_MAX) || pnum > PMASK) {
                        warnx("%s, %zu: port too big `%s'", fname, line, port);
                        continue;
                }

                if (svc[pnum] == NULL) {
                        svc[pnum] = calloc(PROTOMAX, sizeof(StringList *));
                        if (svc[pnum] == NULL)
                                err(1, "Cannot allocate %zu bytes",
                                    (size_t)PROTOMAX);
                }

                pindex = getprotoindex(sl, proto);
                if (svc[pnum][pindex] == NULL)
                        s = svc[pnum][pindex] = sl_init();
                else
                        s = svc[pnum][pindex];

                /* build list of aliases */
                if (sl_find(s, name) == NULL) {
                        char *p2;

                        if ((p2 = strdup(name)) == NULL)
                                err(1, "Cannot copy string");
                        (void)sl_add(s, p2);
                }

                if (aliases) {
                        while ((alias = strsep(&aliases, " \t")) != NULL) {
                                if (alias[0] == '\0')
                                        continue;
                                if (sl_find(s, alias) == NULL) {
                                        char *p2;

                                        if ((p2 = strdup(alias)) == NULL)
                                                err(1, "Cannot copy string");
                                        (void)sl_add(s, p2);
                                }
                        }
                }
        }
        (void)fclose(fp);
        return svc;
}

/*
 * cleanup(): Remove temporary files upon exit
 */
static void
cleanup(void)
{
        if (tname[0])
                (void)unlink(tname);
}

static char *
getstring(const char *fname, size_t line, char **cp, const char *tag)
{
        char *str;

        while ((str = strsep(cp, " \t")) != NULL && *str == '\0')
                continue;

        if (str == NULL)
                warnx("%s, %zu: no %s found", fname, line, tag);

        return str;
}

static void
killproto(DBT *key)
{
        char *p, *d = key->data;

        if ((p = strchr(d, '/')) == NULL)
                abort();
        *p++ = '\0';
        key->size = p - d;
}

static void
store(DB *db, DBT *key, DBT *data, int warndup)
{
#ifdef DEBUG
        int k = key->size - 1;
        int d = data->size - 1;
        (void)printf("store [%*.*s] [%*.*s]\n",
                k, k, (char *)key->data + 1,
                d, d, (char *)data->data + 1);
#endif
        switch ((db->put)(db, key, data, R_NOOVERWRITE)) {
        case 0:
                break;
        case 1:
                if (warndup)
                        warnx("duplicate service `%s'",
                            &((char *)key->data)[1]);
                break;
        case -1:
                err(1, "put");
                break;
        default:
                abort();
                break;
        }
}

static size_t
getprotoindex(StringList *sl, const char *str)
{
        size_t i;
        char *p;

        for (i= 0; i < sl->sl_cur; i++)
                if (strcmp(sl->sl_str[i], str) == 0)
                        return i;

        if (i == PROTOMAX)
                errx(1, "Ran out of protocols adding `%s';"
                    " recompile with larger PROTOMAX", str);
        if ((p = strdup(str)) == NULL)
                err(1, "Cannot copy string");
        (void)sl_add(sl, p);
        return i;
}

static const char *
getprotostr(StringList *sl, size_t i)
{
        assert(i < sl->sl_cur);
        return sl->sl_str[i];
}

static const char *
mkaliases(StringList *sl, char *buf, size_t len)
{
        size_t nc, i, pos;

        buf[0] = 0;
        for (i = 1, pos = 0; i < sl->sl_cur; i++) {
                nc = strlcpy(buf + pos, sl->sl_str[i], len);
                if (nc >= len)
                        goto out;
                pos += nc;
                len -= nc;
                nc = strlcpy(buf + pos, " ", len);
                if (nc >= len)
                        goto out;
                pos += nc;
                len -= nc;
        }
        return buf;
out:
        warn("aliases for `%s' truncated", sl->sl_str[0]);
        return buf;
}

static void
usage(void)
{
        (void)fprintf(stderr,
            "Usage:\t%s [-b | -l] [-q] [-o <db>] [<servicefile>]\n"
            "\t%s -u [<servicefile>]\n", getprogname(), getprogname());
        exit(1);
}