/*      $NetBSD: catopen.c,v 1.34 2025/12/16 12:39:02 nia Exp $ */

/*-
 * Copyright (c) 1996 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by J.T. Conklin.
 *
 * 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/cdefs.h>
__RCSID("$NetBSD: catopen.c,v 1.34 2025/12/16 12:39:02 nia Exp $");

#define _NLS_PRIVATE
#define __SETLOCALE_SOURCE__

#include "namespace.h"
#include <sys/param.h>
#include <sys/endian.h>
#include <sys/stat.h>
#include <sys/mman.h>

#include <assert.h>
#include <fcntl.h>
#include <limits.h>
#include <locale.h>
#include <nl_types.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "citrus_namespace.h"
#include "citrus_bcs.h"
#include "citrus_region.h"
#include "citrus_lookup.h"
#include "citrus_aliasname_local.h"
#include "setlocale_local.h"

#define NLS_ALIAS_DB "/usr/share/nls/nls.alias"

#define NLS_DEFAULT_PATH "/usr/share/nls/%L/%N.cat:/usr/share/nls/%N/%L"
#define NLS_DEFAULT_LANG "C"

__weak_alias(catopen, _catopen)
__weak_alias(catopen_l, _catopen_l)

static nl_catd load_msgcat(const char *);

nl_catd
catopen(const char *name, int oflag)
{

        return catopen_l(name, oflag, _current_locale());
}

nl_catd
catopen_l(const char *name, int oflag, locale_t loc)
{
        char tmppath[PATH_MAX+1];
        const char *nlspath;
        const char *lang, *reallang;
        char *t;
        const char *s, *u;
        nl_catd catd;
        char langbuf[PATH_MAX];

        if (name == NULL || *name == '\0')
                return (nl_catd)-1;

        /* absolute or relative path? */
        if (strchr(name, '/'))
                return load_msgcat(name);

        if (issetugid() || (nlspath = getenv("NLSPATH")) == NULL)
                nlspath = NLS_DEFAULT_PATH;
        /*
         * Historical note:
         * http://www.hauN.org/ml/b-l-j/a/800/828.html (in japanese)
         */
        if (oflag == NL_CAT_LOCALE) {
                lang = loc->part_name[LC_MESSAGES];
        } else {
                lang = getenv("LANG");
        }
        if (lang == NULL || strchr(lang, '/'))
                lang = NLS_DEFAULT_LANG;

        reallang = __unaliasname(NLS_ALIAS_DB, lang, langbuf, sizeof(langbuf));
        if (reallang == NULL)
                reallang = lang;

        s = nlspath;
        t = tmppath;
        do {
                while (*s && *s != ':') {
                        if (*s == '%') {
                                switch (*(++s)) {
                                case 'L':       /* locale */
                                        u = reallang;
                                        while (*u && t < tmppath + PATH_MAX)
                                                *t++ = *u++;
                                        break;
                                case 'N':       /* name */
                                        u = name;
                                        while (*u && t < tmppath + PATH_MAX)
                                                *t++ = *u++;
                                        break;
                                case 'l':       /* lang */
                                case 't':       /* territory */
                                case 'c':       /* codeset */
                                        break;
                                default:
                                        if (t < tmppath + PATH_MAX)
                                                *t++ = *s;
                                }
                        } else {
                                if (t < tmppath + PATH_MAX)
                                        *t++ = *s;
                        }
                        s++;
                }

                *t = '\0';
                catd = load_msgcat(tmppath);
                if (catd != (nl_catd)-1)
                        return catd;

                if (*s)
                        s++;
                t = tmppath;
        } while (*s);

        return (nl_catd)-1;
}

static nl_catd
load_msgcat(const char *path)
{
        struct stat st;
        nl_catd catd;
        void *data;
        int fd;

        _DIAGASSERT(path != NULL);

        if ((fd = open(path, O_RDONLY|O_CLOEXEC)) == -1)
                return (nl_catd)-1;

        if (fstat(fd, &st) != 0) {
                close (fd);
                return (nl_catd)-1;
        }

        data = mmap(0, (size_t)st.st_size, PROT_READ, MAP_FILE|MAP_SHARED, fd,
            (off_t)0);
        close (fd);

        if (data == MAP_FAILED) {
                return (nl_catd)-1;
        }

        if (ntohl((u_int32_t)((struct _nls_cat_hdr *)data)->__magic) !=
            _NLS_MAGIC) {
                munmap(data, (size_t)st.st_size);
                return (nl_catd)-1;
        }

        if ((catd = malloc(sizeof (*catd))) == NULL) {
                munmap(data, (size_t)st.st_size);
                return (nl_catd)-1;
        }

        catd->__data = data;
        catd->__size = (int)st.st_size;
        return catd;
}