/*
 * Copyright (c)2004 The DragonFly Project. All rights reserved.
 *
 * 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 DragonFly Project 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 HOLDERS 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.
 */

/*
 * fn_parsers.c
 * Installer Function : Parse /usr/share/zoneinfo/zone.tab.
 * $Id: fn_zonetab.c,v 1.3 2004/07/16 21:04:20 adonijah Exp $
 */

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

#include "fn_zonetab.h"

char *
zt_readfile(char *buf, int len, FILE *f) {
        int i = 0;
        char *cs;

        /* XXX this is kinda ugly */
        cs = buf;
        while (--len > 0 && (i = getc(f)) != EOF)
                *(cs++) = i;
        *cs = '\0';
        return((i == EOF && buf == cs) ? NULL : buf);
}

void
zt_get_token(struct zt_parse *zp) {
        int i = 0;

        while (*(zp->buf) != '\0' && *(zp->buf) != '\n' && *(zp->buf) != '\t') {
                switch (*(zp->buf)) {
                case '#':
                        while (*(zp->buf) != '\n')
                                zp->buf++;
                        zp->buf++;
                        break;
                default:
                        while (*(zp->buf) != '\n' && *(zp->buf) != '\t' &&
                            *(zp->buf) != '\0') {
                                if (*(zp->buf) == '/' && zp->state == ZT_REGION) {
                                        zp->tok[i] = '\0';
                                        return;
                                }
                                zp->tok[i++] = *(zp->buf++);
                        }
                        zp->tok[i] = '\0';
                        if (zp->state == ZT_LOCALE && *(zp->buf) == '\n')
                                zp->state = ZT_LOCALE_ENDL;
                        else if (*(zp->buf) == '\0')
                                zp->state = ZT_NOTOK;
                        break;
                }
        }
}

void
zt_parse(struct zonetab *head) {
        FILE *zone_tab;
        struct stat sb;
        struct zonetab *c;
        struct zt_parse zp;
        char *file;

        zone_tab = fopen(ZONETAB_FILE, "r");
        stat(ZONETAB_FILE, &sb);
        file = malloc(sb.st_size + 1);
        file = zt_readfile(file, sb.st_size, zone_tab);
        zp.buf = file;

        zp.state = ZT_CC;
        c = head;

        do {
                zt_get_token(&zp);
                switch (zp.state) {
                case ZT_CC:
                        c->zt_cc = strdup(zp.tok);
                        zp.state = ZT_COORDS;
                        break;
                case ZT_COORDS:
                        c->zt_coords = strdup(zp.tok);
                        zp.state = ZT_REGION;
                        break;
                case ZT_REGION:
                        c->zt_region = strdup(zp.tok);
                        zp.state = ZT_LOCALE;
                        break;
                case ZT_LOCALE:
                        c->zt_locale = strdup(zp.tok);
                        zp.state = ZT_COMMENTS;
                        break;
                case ZT_LOCALE_ENDL:
                        c->zt_locale = strdup(zp.tok);
                        c->zt_comments = NULL;
                        c->next = malloc(sizeof(struct zonetab));
                        c = c->next;
                        zp.state = ZT_CC;
                        break;
                case ZT_COMMENTS:
                        c->zt_comments = strdup(zp.tok);
                        c->next = malloc(sizeof(struct zonetab));
                        c = c->next;
                        zp.state = ZT_CC;
                        break;
                case ZT_NOTOK:
                        goto done;
                }
                zp.buf++;
        } while (1);

done:
        c->next = NULL;
        free(file);
}