farsamiscutilities.cpp

/********************************************************************************
 *  FARSA Utilities Library                                                     *
 *  Copyright (C) 2007-2012                                                     *
 *  Gianluca Massera <emmegian@yahoo.it>                                        *
 *  Stefano Nolfi <stefano.nolfi@istc.cnr.it>                                   *
 *  Tomassino Ferrauto <tomassino.ferrauto@istc.cnr.it>                         *
 *                                                                              *
 *  This program is free software; you can redistribute it and/or modify        *
 *  it under the terms of the GNU General Public License as published by        *
 *  the Free Software Foundation; either version 2 of the License, or           *
 *  (at your option) any later version.                                         *
 *                                                                              *
 *  This program is distributed in the hope that it will be useful,             *
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of              *
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               *
 *  GNU General Public License for more details.                                *
 *                                                                              *
 *  You should have received a copy of the GNU General Public License           *
 *  along with this program; if not, write to the Free Software                 *
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA  *
 ********************************************************************************/

#include "farsamiscutilities.h"

namespace farsa {

QString removeComments(const QString& program, CommentsPositions* commentsPos, StringsPositions* stringsPos)
{
    // We create the list of comments and strings in any case, even if we don't have to return them
    CommentsPositions cpos;
    StringsPositions spos;

    // To remove comments we read one character at a time and check if it is a comment or not
    QString cleaned;
    // The possible states
    enum RemoveCommentsState {
        FirstSlash,
        StartEndCComment,
        InCComment,
        InCppComment,
        InString,
        InCharacter,
        NormalCode
    } state = NormalCode;
    CommentPosition curComment;
    StringPosition curString;
    for (int i = 0; i < program.size(); i++) {
        switch (state) {
            case FirstSlash:
                if (program[i] == '/') {
                    state = InCppComment;
                    curComment.type = CommentPosition::CppComment;
                } else if (program[i] == '*') {
                    state = InCComment;
                    curComment.type = CommentPosition::CComment;
                } else {
                    cleaned += '/';
                    cleaned += program[i];
                    state = NormalCode;

                    // Checking for strings. We don't change or remove them but we have to report them
                    if ((program[i] == '\"') && ((i == 0) || (program[i - 1] != '\\'))) {
                        state = InString;
                        curString.originalStart = i;
                        curString.parsedStart = cleaned.size() - 1;
                        curString.type = StringPosition::String;
                    } else if ((program[i] == '\'') && ((i == 0) || (program[i - 1] != '\\'))) {
                        state = InCharacter;
                        curString.originalStart = i;
                        curString.parsedStart = cleaned.size() - 1;
                        curString.type = StringPosition::Character;
                    }
                }
                break;
            case StartEndCComment:
                state = InCComment;
                if (program[i] == '/') {
                    state = NormalCode;
                    // Adding a whitespace for the cases of comments between two elements which should be separated
                    cleaned += ' ';
                    curComment.originalEnd = i;
                    curComment.parsedPosition = cleaned.size() - 1;
                    cpos.append(curComment);
                } else if (program[i] == '*') {
                    state = StartEndCComment;
                }
                break;
            case InCComment:
                if (program[i] == '*') {
                    state = StartEndCComment;
                }
                break;
            case InCppComment:
                if ((program[i] == '\n') || (program[i] == '\r')) {
                    cleaned += program[i];
                    state = NormalCode;
                    curComment.originalEnd = i - 1;
                    curComment.parsedPosition = cleaned.size() - 1;
                    cpos.append(curComment);
                }
                break;
            case InString:
                cleaned += program[i];

                if ((program[i] == '"') && ((i == 0) || (program[i - 1] != '\\'))) {
                    state = NormalCode;
                    curString.originalEnd = i;
                    curString.parsedEnd = cleaned.size() - 1;
                    spos.append(curString);
                }
                break;
            case InCharacter:
                cleaned += program[i];

                // Here we don't check that there is only one character enclosed in '',
                // the code won't compile anyway if there is more than one character
                if ((program[i] == '\'') && ((i == 0) || (program[i - 1] != '\\'))) {
                    state = NormalCode;
                    curString.originalEnd = i;
                    curString.parsedEnd = cleaned.size() - 1;
                    spos.append(curString);
                }
                break;
            case NormalCode:
                if (program[i] == '/') {
                    state = FirstSlash;
                    curComment.originalStart = i;
                } else {
                    cleaned += program[i];

                    // Checking for strings. We don't change or remove them but we have to report them
                    if ((program[i] == '\"') && ((i == 0) || (program[i - 1] != '\\'))) {
                        state = InString;
                        curString.originalStart = i;
                        curString.parsedStart = cleaned.size() - 1;
                        curString.type = StringPosition::String;
                    } else if ((program[i] == '\'') && ((i == 0) || (program[i - 1] != '\\'))) {
                        state = InCharacter;
                        curString.originalStart = i;
                        curString.parsedStart = cleaned.size() - 1;
                        curString.type = StringPosition::Character;
                    }
                }
                break;
        }
    }

    // Whe have to check if we are still in a comment or string/character to add it
    switch (state) {
        case StartEndCComment:
        case InCComment:
        case InCppComment:
            cleaned += ' ';
            curComment.originalEnd = program.size() - 1;
            curComment.parsedPosition = cleaned.size() - 1;
            cpos.append(curComment);
            break;
        case InString:
        case InCharacter:
            curString.originalEnd = program.size() - 1;
            curString.parsedEnd = cleaned.size() - 1;
            spos.append(curString);
            break;
        default:
            break;
    }

    if (commentsPos != NULL) {
        *commentsPos = cpos;
    }
    if (stringsPos != NULL) {
        *stringsPos = spos;
    }

    return cleaned;
}

} // end namespace farsa