/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1987, 1993, 1994
 *      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>
#include <ctype.h>
#include <limits.h>
#include <stdio.h>

#include "ctags.h"

/*
 * y_entries:
 *      find the yacc tags and put them in.
 */
void
y_entries(void)
{
        int     c;
        char    *sp;
        bool    in_rule;
        char    tok[MAXTOKEN];

        in_rule = false;

        while (GETC(!=, EOF))
                switch (c) {
                case '\n':
                        SETLINE;
                        /* FALLTHROUGH */
                case ' ':
                case '\f':
                case '\r':
                case '\t':
                        break;
                case '{':
                        if (skip_key('}'))
                                in_rule = false;
                        break;
                case '\'':
                case '"':
                        if (skip_key(c))
                                in_rule = false;
                        break;
                case '%':
                        if (GETC(==, '%'))
                                return;
                        (void)ungetc(c, inf);
                        break;
                case '/':
                        if (GETC(==, '*') || c == '/')
                                skip_comment(c);
                        else
                                (void)ungetc(c, inf);
                        break;
                case '|':
                case ';':
                        in_rule = false;
                        break;
                default:
                        if (in_rule || (!isalpha(c) && c != '.' && c != '_'))
                                break;
                        sp = tok;
                        *sp++ = c;
                        while (GETC(!=, EOF) && (intoken(c) || c == '.'))
                                *sp++ = c;
                        *sp = EOS;
                        get_line();             /* may change before ':' */
                        while (iswhite(c)) {
                                if (c == '\n')
                                        SETLINE;
                                if (GETC(==, EOF))
                                        return;
                        }
                        if (c == ':') {
                                pfnote(tok, lineno);
                                in_rule = true;
                        }
                        else
                                (void)ungetc(c, inf);
                }
}

/*
 * toss_yysec --
 *      throw away lines up to the next "\n%%\n"
 */
void
toss_yysec(void)
{
        int     c;                      /* read character */
        int     state;

        /*
         * state == 0 : waiting
         * state == 1 : received a newline
         * state == 2 : received first %
         * state == 3 : received second %
         */
        lineftell = ftell(inf);
        for (state = 0; GETC(!=, EOF);)
                switch (c) {
                case '\n':
                        ++lineno;
                        lineftell = ftell(inf);
                        if (state == 3)         /* done! */
                                return;
                        state = 1;              /* start over */
                        break;
                case '%':
                        if (state)              /* if 1 or 2 */
                                ++state;        /* goto 3 */
                        break;
                default:
                        state = 0;              /* reset */
                        break;
                }
}