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/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QLALR module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights. These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <cstdlib>
#include <cstdio>
enum Token {
EOF_SYMBOL,
LEFT_ANGLE,
RIGHT_ANGLE,
ANY,
};
static int current_char;
static int yytoken;
static bool in_tag = false;
bool parseXmlStream();
bool parseTagOrWord();
bool parseTagName();
inline int nextToken()
{
current_char = fgetc(stdin);
if (current_char == EOF) {
return (yytoken = EOF_SYMBOL);
} else if (current_char == '<') {
in_tag = true;
return (yytoken = LEFT_ANGLE);
} else if (in_tag && current_char == '>') {
in_tag = false;
return (yytoken = RIGHT_ANGLE);
}
return (yytoken = ANY);
}
bool parse()
{
nextToken();
return parseXmlStream();
}
bool parseXmlStream()
{
while (parseTagOrWord())
;
return true;
}
bool parseTagOrWord()
{
if (yytoken == LEFT_ANGLE) {
nextToken();
if (! parseTagName())
return false;
if (yytoken != RIGHT_ANGLE)
return false;
nextToken();
fprintf (stderr, "*** found a tag\n");
} else if (yytoken == ANY) {
nextToken();
} else {
return false;
}
return true;
}
bool parseTagName()
{
while (yytoken == ANY)
nextToken();
return true;
}
int main()
{
if (parse())
printf("OK\n");
else
printf("KO\n");
}
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