CqlParserHelpers.cs source code in C# .NET

                        Code:
                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / DataEntity / System / Data / Common / EntitySql / CqlParserHelpers.cs / 1305376 / CqlParserHelpers.cs
                        
                        
                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// 
// @owner  [....]
// @backupOwner [....] 
//--------------------------------------------------------------------- 

namespace System.Data.Common.EntitySql 
{
    using System;
    using System.Collections.Generic;
    using System.IO; 
    using System.Globalization;
    using System.Data.Common.EntitySql.AST; 
 
    /// 
    /// Represents the Cql Parser engine. Also, implements helpers and util routines. 
    /// 
    internal sealed partial class CqlParser
    {
        private Node _parsedTree; 
        private CqlLexer _lexer;
        private string _query; 
        private ParserOptions _parserOptions; 
        private const string _internalYaccSyntaxErrorMessage = "syntax error";
        ///  
        /// Contains inclusive count of method expressions.
        /// 
        private uint _methodExprCounter;
        private Stack _methodExprCounterStack; 

        private string _version = YYMAJOR.ToString(NumberFormatInfo.InvariantInfo) + '.' + YYMINOR.ToString(NumberFormatInfo.InvariantInfo); 
 
        internal CqlParser( ParserOptions parserOptions, bool debug )
        { 
            // The common practice is to make the null check at the public surface,
            // however this method is a convergence zone from multiple public entry points and it makes sense to
            // check for null once, here.
            EntityUtil.CheckArgumentNull(parserOptions, "parserOptions"); 

            _parserOptions = parserOptions; 
            yydebug = debug; 
        }
 
        /// 
        /// Main entry point for parsing cql.
        /// 
        /// query text 
        /// Thrown when Syntatic rules are violated and the query cannot be accepted
        /// Abstract Syntax Tree 
        internal Node Parse(string query) 
        {
            // The common practice is to make the null check at the public surface, 
            // however this method is a convergence zone from multiple public entry points and it makes sense to
            // check for null once, here.
            EntityUtil.CheckArgumentNull(query, "query");
            if (String.IsNullOrEmpty(query) || query.Trim().Length == 0) 
            {
                throw EntityUtil.Argument(System.Data.Entity.Strings.InvalidEmptyQueryTextArgument); 
            } 

            _query = query; 
            _parsedTree = null;
            _parserOptions = _parserOptions.MakeReadOnly();
            _methodExprCounter = 0;
            _methodExprCounterStack = new Stack(); 
            internalParseEntryPoint();
            return _parsedTree; 
        } 

        ///  
        /// Returns query string
        /// 
        internal string Query
        { 
            get { return _query; }
        } 
 
#if EXTRA_ENTITYSQL_PARSER_DEBUGGING
        ///  
        /// Enables/Disables yacc debugging.
        /// 
        internal bool EnableDebug
        { 
            get { return yydebug; }
            set { yydebug = value; } 
        } 
#endif
 
        /// 
        /// Returns ParserOptions used
        /// 
        /// Once parse has been invoked, ParserOptions are frozen and cannot be changed. otherwise a EntityException exception will be thrown 
        internal ParserOptions ParserOptions
        { 
            get { return _parserOptions; } 
        }
 

        /// 
        /// Internal entry point
        ///  
        private void internalParseEntryPoint()
        { 
            _lexer = new CqlLexer(Query, ParserOptions); 
#if EXTRA_ENTITYSQL_PARSER_DEBUGGING
            CqlLexer.Token tk = lexer.yylex(); 
            while (null != tk)
            {
                Console.WriteLine("{0} := {1}", tk.TokenId, lexer.yytext());
                tk = lexer.yylex(); 
            }
#endif 
            yyparse(); 
        }
 

        //
        // Conversion/Cast/Helpers
        // 
        private static Node AstNode(object o) { return ((Node)o); }
        private static int AstNodePos( object o ) { return ((Node)o).ErrCtx.InputPosition; } 
        private static CqlLexer.TerminalToken Terminal( object o ) { return ((CqlLexer.TerminalToken)o); } 
        private static int TerminalPos( object o ) { return ((CqlLexer.TerminalToken)o).IPos; }
        private static NodeList ToNodeList(object o) where T : Node { return ((NodeList)o); } 


        private short yylex()
        { 
            CqlLexer.Token token = null;
            token = _lexer.yylex(); 
            if (null == token) 
            {
                return 0; 
            }
            _lexer.AdvanceIPos();
            yylval = token.Value;
            return token.TokenId; 
        }
 
 
        private void yyerror_stackoverflow()
        { 
            yyerror(System.Data.Entity.Strings.StackOverflowInParser);
        }

 
        private void yyerror( string s )
        { 
            if (s.Equals(_internalYaccSyntaxErrorMessage, StringComparison.Ordinal)) 
            {
                int errorPosition = _lexer.IPos; 
                string syntaxContextInfo = null;
                string term = _lexer.YYText;
                if (!String.IsNullOrEmpty(term))
                { 
                    syntaxContextInfo = System.Data.Entity.Strings.LocalizedTerm;
                    ErrorContext errCtx = null; 
                    Node astNode = yylval as Node; 
                    if (null != astNode && (null != astNode.ErrCtx) && (!String.IsNullOrEmpty(astNode.ErrCtx.ErrorContextInfo)))
                    { 
                        errCtx = astNode.ErrCtx;
                        errorPosition = Math.Min(errorPosition, errorPosition - term.Length);
                    }
 
                    if ((yylval is CqlLexer.TerminalToken) && CqlLexer.IsReservedKeyword(term) && !(astNode is Identifier))
                    { 
                        syntaxContextInfo = System.Data.Entity.Strings.LocalizedKeyword; 
                        term = term.ToUpperInvariant();
                        errorPosition = Math.Min(errorPosition, errorPosition - term.Length); 
                    }
                    else if (null != errCtx)
                    {
                        syntaxContextInfo = EntityRes.GetString(errCtx.ErrorContextInfo); 
                    }
 
                    syntaxContextInfo = String.Format(CultureInfo.CurrentCulture, "{0} '{1}'", syntaxContextInfo, term); 
                }
 
                throw EntityUtil.EntitySqlError(_query,
                                     System.Data.Entity.Strings.GenericSyntaxError,
                                     errorPosition,
                                     syntaxContextInfo, 
                                     false /* loadErrorContextInfoFromResource */);
            } 
            throw EntityUtil.EntitySqlError(_query, s, _lexer.IPos); 
        }
 
        //
        // Error tracking helpers
        //
        private void SetErrCtx(Node astExpr, CqlLexer.TerminalToken tokenValue, string info) 
        {
            SetErrCtx(astExpr, tokenValue.IPos, info); 
        } 

        private void SetErrCtx(Node astExpr, int inputPos, string info) 
        {
            astExpr.ErrCtx.InputPosition = inputPos;
            astExpr.ErrCtx.ErrorContextInfo = info;
            astExpr.ErrCtx.CommandText = _query; 
        }
 
        private void StartMethodExprCounting() 
        {
            // Save the current counter value. 
            _methodExprCounterStack.Push(_methodExprCounter);

            // Reset the counter for the current level.
            _methodExprCounter = 0; 
        }
 
        private void IncrementMethodExprCount() 
        {
            ++_methodExprCounter; 
        }

        private uint EndMethodExprCounting()
        { 
            // Save number of method expressions on the current level.
            uint count = _methodExprCounter; 
 
            // Restore upper level counter and adjust it with the number of method expressions on the current level.
            _methodExprCounter += _methodExprCounterStack.Pop(); 

            return count;
        }
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
CqlParserHelpers.cs source code in C# .NET

Source code for the .NET framework in C#

Code:

Link Menu
