preprocessor.cpp

cppcheck is a static C/C++ code analyzer that checks for memory leaks, mismatching allocation-deallo

        }

        if (line.find("#file \"") == 0 ||
            line.find("#endfile") == 0)
        {
            // We must not remove #file tags or line numbers
            // are corrupted. File tags are removed by the tokenizer.
        }
        else if (!match ||
                 line.find("#if") == 0 ||
                 line.find("#else") == 0 ||
                 line.find("#elif") == 0 ||
                 line.find("#endif") == 0)
            line = "";

        ret << line << "\n";
    }

    return expandMacros(ret.str());
}

std::string Preprocessor::getHeaderFileName(const std::string &str)
{
    std::string result;
    std::string::size_type i = str.find("\"");
    if (i == std::string::npos)
        return result;

    for (i = i + 1; i < str.length(); ++i)
    {
        if (str[i] == '"')
            break;

        result.append(1, str[i]);
    }

    return result;
}

void Preprocessor::handleIncludes(std::string &code, const std::string &filename, const std::list<std::string> &includePaths)
{
//    std::string line;
    std::string path = filename;
    path.erase(1 + path.find_last_of("\\/"));
    std::string::size_type pos = 0;
    std::map<std::string, bool> handledFiles;
    while ((pos = code.find("#include", pos)) != std::string::npos)
    {
        // Accept only includes that are at the start of a line
        if (pos > 0 && code[pos-1] != '\n')
        {
            pos += 8; // length of "#include"
            continue;
        }

        std::string::size_type end = code.find("\n", pos);
        std::string filename = code.substr(pos, end - pos);

        // Remove #include clause
        code.erase(pos, end - pos);

        filename = getHeaderFileName(filename);
        if (filename.length() == 0)
            continue;

        std::string tempFile = filename;
        std::transform(tempFile.begin(), tempFile.end(), tempFile.begin(), static_cast < int(*)(int) > (std::tolower));
        if (handledFiles.find(tempFile) != handledFiles.end())
        {
            // We have processed this file already once, skip
            // it this time to avoid ethernal loop.
            continue;
        }

        handledFiles[ tempFile ] = true;

        // filename contains now a file name e.g. "menu.h"
        std::string processedFile;
        for (std::list<std::string>::const_iterator iter = includePaths.begin(); iter != includePaths.end(); ++iter)
        {
            std::ifstream fin;
            fin.open((*iter + filename).c_str());
            if (fin.is_open())
            {
                filename = *iter + filename;
                processedFile = Preprocessor::read(fin);
                break;
            }
        }

        if (processedFile.length() == 0)
        {
            filename = path + filename;
            std::ifstream fin(filename.c_str());
            processedFile = Preprocessor::read(fin);
        }

        if (processedFile.length() > 0)
        {
            // Replace all tabs with spaces..
            std::replace(processedFile.begin(), processedFile.end(), '\t', ' ');

            // Remove all indentation..
            if (!processedFile.empty() && processedFile[0] == ' ')
                processedFile.erase(0, processedFile.find_first_not_of(" "));

            // Remove space characters that are after or before new line character
            processedFile = removeSpaceNearNL(processedFile);
            processedFile = "#file \"" + filename + "\"\n" + processedFile + "\n#endfile";
            code.insert(pos, processedFile);

        }
    }
}

class Macro
{
private:
    Tokenizer tokenizer;
    std::vector<std::string> _params;
    std::string _name;
    std::string _macro;
    bool _variadic;

public:
    Macro(const std::string &macro)
            : _macro(macro)
    {
        // Tokenize the macro to make it easier to handle
        std::istringstream istr(macro.c_str());
        tokenizer.tokenize(istr, "");

        // macro name..
        if (tokens() && tokens()->isName())
            _name = tokens()->str();

        _variadic = false;

        std::string::size_type pos = macro.find_first_of(" (");
        if (pos != std::string::npos && macro[pos] == '(')
        {
            // Extract macro parameters
            if (Token::Match(tokens(), "%var% ( %var%"))
            {
                for (const Token *tok = tokens()->tokAt(2); tok; tok = tok->next())
                {
                    if (tok->str() == ")")
                        break;
                    if (Token::Match(tok, ". . . )"))
                    {
                        _variadic = true;
                        break;
                    }
                    if (tok->isName())
                        _params.push_back(tok->str());
                }
            }
        }
    }

    const Token *tokens() const
    {
        return tokenizer.tokens();
    }

    const std::vector<std::string> params() const
    {
        return _params;
    }

    bool variadic() const
    {
        return _variadic;
    }

    const std::string &name() const
    {
        return _name;
    }

    const std::string code(const std::vector<std::string> &params2) const
    {
        std::string macrocode;

        if (_params.empty())
        {
            std::string::size_type pos = _macro.find(" ");
            if (pos == std::string::npos)
                macrocode = "";
            else
            {
                macrocode = _macro.substr(pos + 1);
                if ((pos = macrocode.find_first_of("\r\n")) != std::string::npos)
                    macrocode.erase(pos);
            }
        }

        else
        {
            const Token *tok = tokens();
            while (tok && tok->str() != ")")
                tok = tok->next();
            if (tok)
            {
                bool optcomma = false;
                while ((tok = tok->next()) != NULL)
                {
                    std::string str = tok->str();
                    if (str == "##")
                        continue;
                    if (str[0] == '#' || tok->isName())
                    {
                        bool stringify = false;
                        if (str[0] == '#')
                        {
                            str = str.erase(0, 1);
                            stringify = true;
                        }
                        for (unsigned int i = 0; i < _params.size(); ++i)
                        {
                            if (str == _params[i])
                            {
                                if (_variadic && i == _params.size() - 1)
                                {
                                    str = "";
                                    for (unsigned int j = _params.size() - 1; j < params2.size(); ++j)
                                    {
                                        if (optcomma || j > _params.size() - 1)
                                            str += ",";
                                        optcomma = false;
                                        str += params2[j];
                                    }
                                    break;
                                }
                                if (stringify)
                                    str = "\"" + params2[i] + "\"";
                                else
                                    str = params2[i];
                                break;
                            }
                        }
                    }
                    if (_variadic && Token::Match(tok, ",") && tok->next() && Token::Match(tok->next(), "##"))
                    {
                        optcomma = true;
                        continue;
                    }
                    optcomma = false;
                    macrocode += str;
                    if (Token::Match(tok, "%type% %var%"))
                        macrocode += " ";
                }
            }
        }

        return macrocode;
    }
};

std::string Preprocessor::expandMacros(std::string code)
{
    // Search for macros and expand them..
    std::string::size_type defpos = 0;
    while ((defpos = code.find("#define ", defpos)) != std::string::npos)
    {
        if (defpos > 0 && code[defpos-1] != '\n')
        {
            defpos += 6;
            continue;
        }

        // Get macro..
        std::string::size_type endpos = code.find("\n", defpos + 6);
        if (endpos == std::string::npos)
        {
            code.erase(defpos);
            break;
        }

        // Extract the whole macro into a separate variable "macro" and then erase it from "code"
        const Macro macro(code.substr(defpos + 8, endpos - defpos - 7));
        code.erase(defpos, endpos - defpos);

        // No macro name => continue
        if (macro.name() == "")
            continue;

        // Expand all macros in the code..
        char pattern[5] = "\"'# ";
        pattern[3] = macro.name().at(0);
        std::string::size_type pos1 = defpos;
        while ((pos1 = code.find_first_of(pattern, pos1 + 1)) != std::string::npos)
        {
            char ch = code[pos1];

            // #undef => break
            if (code[pos1] == '#')
            {
                // Are we at a #undef or #define?
                if (code.substr(pos1, 7) == "#undef ")
                    pos1 += 7;
                else if (code.substr(pos1, 8) == "#define ")
                    pos1 += 8;
                else
                    continue;

                // Compare the macroname with the macroname we're currently parsing (macro.name())
                // If it's the same macroname.. break.
                std::string::size_type pos = pos1 + macro.name().length();
                if (pos < code.length()
                    && code.substr(pos1, macro.name().length()) == macro.name()
                    && !std::isalnum(code[pos]) && code[pos] != '_')
                    break;


                continue;
            }

            // String or char..
            if (code[pos1] == '\"' || code[pos1] == '\'')
            {
                //char ch = code[pos1];
                ++pos1;
                while (code[pos1] != ch)
                {
                    if (code[pos1] == '\\')
                        ++pos1;
                    ++pos1;

                    if (!code[pos1])
                    {
                        // This should not happen, if it does, there is a bug in cppcheck.
                        std::cout << "\n\n####### There is a bug in preprocessor.cpp that can cause crash, shutting down.\n\n" << std::endl;
                        std::exit(0);
                    }
                }
                continue;
            }

            // Matching the macroname?
            const std::string substr(code.substr(pos1, macro.name().length()));
            if (code.substr(pos1, macro.name().length()) != macro.name())
                continue;

            // Previous char must not be alphanumeric or '_'
            if (pos1 != 0 && (std::isalnum(code[pos1-1]) || code[pos1-1] == '_'))
                continue;

            // The char after the macroname must not be alphanumeric or '_'
            if (pos1 + macro.name().length() < code.length())
            {
                std::string::size_type pos2 = pos1 + macro.name().length();
                if (std::isalnum(code[pos2]) || code[pos2] == '_')
                    continue;
            }

            std::vector<std::string> params;
            std::string::size_type pos2 = pos1 + macro.name().length();
            if (macro.params().size() && pos2 >= code.length())
                continue;
            if (macro.params().size())
            {
                if (code[pos2] != '(')
                    continue;

                int parlevel = 0;
                std::string par;
                for (; pos2 < code.length(); ++pos2)
                {
                    if (code[pos2] == '(')
                    {
                        ++parlevel;
                        if (parlevel == 1)
                            continue;
                    }
                    else if (code[pos2] == ')')
                    {
                        --parlevel;
                        if (parlevel <= 0)
                        {
                            params.push_back(par);
                            break;
                        }
                    }
                    else if (code[pos2] == '\"' || code[pos2] == '\'')
                    {
                        par += code[pos2];
                        char ch = code[pos2];
                        ++pos2;
                        while (pos2 < code.length() && code[pos2] != ch)
                        {
                            par += code[pos2];
                            if (code[pos2] == '\\')
                            {
                                par += code[pos2];
                                ++pos2;
                            }
                            ++pos2;
                        }
                        if (pos2 == code.length())
                            break;
                        par += code[pos2];
                        continue;
                    }

                    if (parlevel == 1 && code[pos2] == ',')
                    {
                        params.push_back(par);
                        par = "";
                    }
                    else if (parlevel >= 1)
                    {
                        par += std::string(1, code[pos2]);
                    }
                }
            }

            // Same number of parameters..
            if (!macro.variadic() && params.size() != macro.params().size())
                continue;

            // Create macro code..
            const std::string macrocode(macro.code(params));

            // Insert macro code..
            if (!macro.params().empty())
                ++pos2;

            code.erase(pos1, pos2 - pos1);
            code.insert(pos1, macrocode);
            pos1 += macrocode.length() - 1;
        }
    }

    // Remove all #undef..
    defpos = 0;
    while ((defpos = code.find("\n#undef ", defpos)) != std::string::npos)
    {
        ++defpos;
        std::string::size_type pos2 = code.find("\n", defpos);
        code.erase(defpos, pos2 - defpos);
    }

    return code;
}