parser.cpp

qt-x11-opensource-src-4.1.4.tar.gz源码

    return m_problems == 0;
}

bool Parser::parseDeclaration(DeclarationAST *&node)
{
    int start = tokenStream->cursor();

    switch(tokenStream->lookAhead()) {

    case ';':
        advance();
        return true;

    case Token_extern:
        return parseLinkageSpecification(node);

    case Token_namespace:
        return parseNamespace(node);

    case Token_using:
        return parseUsing(node);

    case Token_typedef:
        return parseTypedef(node);

    case Token_asm:
        return parseAsmDefinition(node);

    case Token_template:
    case Token_export:
        return parseTemplateDeclaration(node);

    default:
        {
            // tokenStream->rewind(start);

            if (objcp && parseObjcDef(node))
                return true;

            tokenStream->rewind(start);

            AST *storageSpec = 0;
            parseStorageClassSpecifier(storageSpec);

            AST *cv = 0;
            parseCvQualify(cv);

            TypeSpecifierAST *spec = 0;
            if (parseEnumSpecifier(spec) || parseClassSpecifier(spec)) {
                spec->setCvQualify(cv);

                AST *cv2 = 0;
                parseCvQualify(cv2);
                spec->setCv2Qualify(cv2);

                InitDeclaratorListAST *declarators = 0;
                parseInitDeclaratorList(declarators);
                ADVANCE(';', ";");

                SimpleDeclarationAST *ast = CreateNode<SimpleDeclarationAST>(m_pool);
                ast->setStorageSpecifier(storageSpec);
                ast->setTypeSpec(spec);
                ast->setInitDeclaratorList(declarators);
                UPDATE_POS(ast, start, tokenStream->cursor());
                node = ast;

                return true;
            }

            tokenStream->rewind(start);
            return parseDeclarationInternal(node);
        }

    } // end switch
}

bool Parser::parseLinkageSpecification(DeclarationAST *&node)
{
    int start = tokenStream->cursor();

    if (tokenStream->lookAhead() != Token_extern) {
        return false;
    }
    advance();

    LinkageSpecificationAST *ast = CreateNode<LinkageSpecificationAST>(m_pool);

    int startExternType = tokenStream->cursor();
    if (tokenStream->lookAhead() == Token_string_literal) {
        advance();
        AST *externType = CreateNode<AST>(m_pool);
        UPDATE_POS(externType, startExternType, tokenStream->cursor());

        ast->setExternType(externType);
    }

    if (tokenStream->lookAhead() == '{') {
        LinkageBodyAST *linkageBody = 0;
        parseLinkageBody(linkageBody);
        ast->setLinkageBody(linkageBody);
    } else {
        DeclarationAST *decl = 0;
        if (!parseDeclaration(decl)) {
            reportError(i18n("Declaration syntax error"));
        }
        ast->setDeclaration(decl);
    }

    UPDATE_POS(ast, start, tokenStream->cursor());

    node = ast;

    return true;
}

bool Parser::parseLinkageBody(LinkageBodyAST *&node)
{

    int start = tokenStream->cursor();

    if (tokenStream->lookAhead() != '{') {
        return false;
    }
    advance();

    LinkageBodyAST *lba = CreateNode<LinkageBodyAST>(m_pool);
    node = lba;

    while (tokenStream->lookAhead()) {
        int tk = tokenStream->lookAhead();

        if (tk == '}')
            break;

        DeclarationAST *def = 0;
        int startDecl = tokenStream->cursor();
        if (parseDeclaration(def)) {
            node->addDeclaration(def);
        } else {
            // error recovery
            if (startDecl == tokenStream->cursor())
                advance(); // skip at least one token
            skipUntilDeclaration();
        }
    }

    if (tokenStream->lookAhead() != '}') {
        reportError(i18n("} expected"));
    } else
        advance();

    UPDATE_POS(node, start, tokenStream->cursor());
    return true;
}

bool Parser::parseNamespace(DeclarationAST *&node)
{
    int start = tokenStream->cursor();

    if (tokenStream->lookAhead() != Token_namespace) {
        return false;
    }
    advance();

    int startNamespaceName = tokenStream->cursor();
    if (tokenStream->lookAhead() == Token_identifier) {
        advance();
    }
    AST *namespaceName = CreateNode<AST>(m_pool);
    UPDATE_POS(namespaceName, startNamespaceName, tokenStream->cursor());

    if (tokenStream->lookAhead() == '=') {
        // namespace alias
        advance();

        NameAST *name = 0;
        if (parseName(name)) {
            ADVANCE(';', ";");

            NamespaceAliasAST *ast = CreateNode<NamespaceAliasAST>(m_pool);
            ast->setNamespaceName(namespaceName);
            ast->setAliasName(name);
            UPDATE_POS(ast, start, tokenStream->cursor());
            node = ast;
            return true;
        } else {
            reportError(i18n("namespace expected"));
            return false;
        }
    } else if (tokenStream->lookAhead() != '{') {
        reportError(i18n("{ expected"));
        return false;
    }

    NamespaceAST *ast = CreateNode<NamespaceAST>(m_pool);
    ast->setNamespaceName(namespaceName);

    LinkageBodyAST *linkageBody = 0;
    parseLinkageBody(linkageBody);

    ast->setLinkageBody(linkageBody);
    UPDATE_POS(ast, start, tokenStream->cursor());
    node = ast;

    return true;
}

bool Parser::parseUsing(DeclarationAST *&node)
{
    int start = tokenStream->cursor();

    if (tokenStream->lookAhead() != Token_using) {
        return false;
    }
    advance();

    if (tokenStream->lookAhead() == Token_namespace) {
        if (!parseUsingDirective(node)) {
            return false;
        }
        UPDATE_POS(node, start, tokenStream->cursor());
        return true;
    }

    UsingAST *ast = CreateNode<UsingAST>(m_pool);

    int startTypeName = tokenStream->cursor();
    if (tokenStream->lookAhead() == Token_typename) {
        advance();
        AST *tn = CreateNode<AST>(m_pool);
        UPDATE_POS(tn, startTypeName, tokenStream->cursor());
        ast->setTypeName(tn);
    }

    NameAST *name = 0;
    if (!parseName(name))
        return false;

    ast->setName(name);

    ADVANCE(';', ";");

    UPDATE_POS(ast, start, tokenStream->cursor());
    node = ast;

    return true;
}

bool Parser::parseUsingDirective(DeclarationAST *&node)
{
    int start = tokenStream->cursor();

    if (tokenStream->lookAhead() != Token_namespace) {
        return false;
    }
    advance();

    NameAST *name = 0;
    if (!parseName(name)) {
        reportError(i18n("Namespace name expected"));
        return false;
    }

    ADVANCE(';', ";");

    UsingDirectiveAST *ast = CreateNode<UsingDirectiveAST>(m_pool);
    ast->setName(name);
    UPDATE_POS(ast, start, tokenStream->cursor());
    node = ast;

    return true;
}


bool Parser::parseOperatorFunctionId(AST *&node)
{
    int start = tokenStream->cursor();

    if (tokenStream->lookAhead() != Token_operator) {
        return false;
    }
    advance();

    AST *op = 0;
    if (parseOperator(op)) {
        AST *asn = CreateNode<AST>(m_pool);
        node = asn;
        UPDATE_POS(node, start, tokenStream->cursor());
        return true;
    } else {
        // parse cast operator
        AST *cv = 0;
        parseCvQualify(cv);

        TypeSpecifierAST *spec = 0;
        if (!parseSimpleTypeSpecifier(spec)) {
            syntaxError();
            return false;
        }
        spec->setCvQualify(cv);

        AST *cv2 = 0;
        parseCvQualify(cv2);
        spec->setCv2Qualify(cv2);

        AST *ptrOp = 0;
        while (parsePtrOperator(ptrOp))
              ;

        AST *asn = CreateNode<AST>(m_pool);
        node = asn;
        UPDATE_POS(node, start, tokenStream->cursor());
        return true;
    }
}

bool Parser::parseTemplateArgumentList(TemplateArgumentListAST *&node, bool reportError)
{
    int start = tokenStream->cursor();

    TemplateArgumentListAST *ast = CreateNode<TemplateArgumentListAST>(m_pool);

    AST *templArg = 0;
    if (!parseTemplateArgument(templArg))
        return false;
    ast->addArgument(templArg);

    while (tokenStream->lookAhead() == ',') {
        advance();

        if (!parseTemplateArgument(templArg)) {
            if (reportError) {
               syntaxError();
               break;
            } else
               return false;
        }
        ast->addArgument(templArg);
    }

    UPDATE_POS(ast, start, tokenStream->cursor());
    node = ast;

    return true;
}

bool Parser::parseTypedef(DeclarationAST *&node)
{
    int start = tokenStream->cursor();

    if (tokenStream->lookAhead() != Token_typedef) {
        return false;
    }
    advance();

    TypeSpecifierAST *spec = 0;
    if (!parseTypeSpecifierOrClassSpec(spec)) {
        reportError(i18n("Need a type specifier to declare"));
        return false;
    }

    InitDeclaratorListAST *declarators = 0;
    if (!parseInitDeclaratorList(declarators)) {
        //reportError(i18n("Need an identifier to declare"));
        //return false;
    }

    ADVANCE(';', ";");

    TypedefAST *ast = CreateNode<TypedefAST>(m_pool);
    ast->setTypeSpec(spec);
    ast->setInitDeclaratorList(declarators);
    UPDATE_POS(ast, start, tokenStream->cursor());
    node = ast;

    return true;
}

bool Parser::parseAsmDefinition(DeclarationAST *&node)
{
    int start = tokenStream->cursor();

    ADVANCE(Token_asm, "asm");

    AST *cv = 0;
    parseCvQualify(cv);

    skip('(', ')');
    advance();
    ADVANCE(';', ";");

    DeclarationAST *ast = CreateNode<DeclarationAST>(m_pool);
    UPDATE_POS(ast, start, tokenStream->cursor());
    node = ast;

    return true;
}

bool Parser::parseTemplateDeclaration(DeclarationAST *&node)
{
    int start = tokenStream->cursor();

    AST *exp = 0;

    int startExport = tokenStream->cursor();
    if (tokenStream->lookAhead() == Token_export) {
        advance();
        AST *n = CreateNode<AST>(m_pool);
        UPDATE_POS(n, startExport, tokenStream->cursor());
        exp = n;
    }

    if (tokenStream->lookAhead() != Token_template) {
        return false;
    }
    advance();

    TemplateParameterListAST *params = 0;
    if (tokenStream->lookAhead() == '<') {
        advance();
        parseTemplateParameterList(params);

        ADVANCE('>', ">");
    }

    DeclarationAST *def = 0;
    if (!parseDeclaration(def)) {
        reportError(i18n("expected a declaration"));
    }

    TemplateDeclarationAST *ast = CreateNode<TemplateDeclarationAST>(m_pool);
    ast->setExported(exp);
    ast->setTemplateParameterList(params);
    ast->setDeclaration(def);
    UPDATE_POS(ast, start, tokenStream->cursor());
    node = ast;

    return true;
}

bool Parser::parseOperator(AST *&/*node*/)
{
    QString text = tokenStream->currentTokenText();

    switch(tokenStream->lookAhead()) {
    case Token_new:
    case Token_delete:
        advance();
        if (tokenStream->lookAhead() == '[' && tokenStream->lookAhead(1) == ']') {
            advance();
            advance();
            text += "[]";
        }
        return true;

    case '+':
    case '-':
    case '*':
    case '/':
    case '%':
    case '^':
    case '&':
    case '|':
    case '~':
    case '!':
    case '=':
    case '<':
    case '>':
    case ',':
    case Token_assign:
    case Token_shift:
    case Token_eq:
    case Token_not_eq:
    case Token_leq:
    case Token_geq:
    case Token_and:
    case Token_or:
    case Token_incr:
    case Token_decr:
    case Token_ptrmem:
    case Token_arrow:
        advance();
        return true;

    default:
        if (tokenStream->lookAhead() == '(' && tokenStream->lookAhead(1) == ')') {
            advance();
            advance();
            return true;
        } else if (tokenStream->lookAhead() == '[' && tokenStream->lookAhead(1) == ']') {
            advance();
            advance();
            return true;
        }
    }

    return false;
}

bool Parser::parseCvQualify(AST *&node)
{
    int start = tokenStream->cursor();

    AST *ast = CreateNode<AST>(m_pool);

    int n = 0;
    while (tokenStream->lookAhead()) {
        int tk = tokenStream->lookAhead();
        if (tk == Token_const || tk == Token_volatile) {
            ++n;
            int startWord = tokenStream->cursor();
            advance();
            AST *word = CreateNode<AST>(m_pool);
            UPDATE_POS(word, startWord, tokenStream->cursor());
            word->setParent(ast);
        } else
            break;
    }

    if (n == 0)
        return false;


    UPDATE_POS(ast, start, tokenStream->cursor());

    node = ast;