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#if MYSQL_6_10
// Copyright ?2004, 2016, Oracle and/or its affiliates. All rights reserved.
//
// MySQL Connector/NET is licensed under the terms of the GPLv2
// <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most
// MySQL Connectors. There are special exceptions to the terms and
// conditions of the GPLv2 as it is applied to this software, see the
// FLOSS License Exception
// <http://www.mysql.com/about/legal/licensing/foss-exception.html>.
//
// 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; version 2 of the License.
//
// 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
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Text;
namespace Externals.MySql.Data.Common
{
internal class MySqlTokenizer
{
private string _sql;
public MySqlTokenizer()
{
BackslashEscapes = true;
MultiLine = true;
Position = 0;
}
public MySqlTokenizer(string input)
: this()
{
_sql = input;
}
#region Properties
public string Text
{
get { return _sql; }
set { _sql = value; Position = 0; }
}
public bool AnsiQuotes { get; set; }
public bool BackslashEscapes { get; set; }
public bool MultiLine { get; set; }
public bool SqlServerMode { get; set; }
public bool Quoted { get; private set; }
public bool IsComment { get; private set; }
public int StartIndex { get; set; }
public int StopIndex { get; set; }
public int Position { get; set; }
public bool ReturnComments { get; set; }
#endregion
public List<string> GetAllTokens()
{
List<string> tokens = new List<string>();
string token = NextToken();
while (token != null)
{
tokens.Add(token);
token = NextToken();
}
return tokens;
}
public string NextToken()
{
while (FindToken())
{
string token = _sql.Substring(StartIndex, StopIndex - StartIndex);
return token;
}
return null;
}
public static bool IsParameter(string s)
{
if (String.IsNullOrEmpty(s)) return false;
if (s[0] == '?') return true;
return s.Length > 1 && s[0] == '@' && s[1] != '@';
}
public string NextParameter()
{
while (FindToken())
{
if ((StopIndex - StartIndex) < 2) continue;
char c1 = _sql[StartIndex];
char c2 = _sql[StartIndex + 1];
if (c1 == '?' ||
(c1 == '@' && c2 != '@'))
return _sql.Substring(StartIndex, StopIndex - StartIndex);
}
return null;
}
public bool FindToken()
{
IsComment = Quoted = false; // reset our flags
StartIndex = StopIndex = -1;
while (Position < _sql.Length)
{
char c = _sql[Position++];
if (Char.IsWhiteSpace(c)) continue;
if (c == '`' || c == '\'' || c == '"' || (c == '[' && SqlServerMode))
ReadQuotedToken(c);
else if (c == '#' || c == '-' || c == '/')
{
if (!ReadComment(c))
ReadSpecialToken();
}
else
ReadUnquotedToken();
if (StartIndex != -1) return true;
}
return false;
}
public string ReadParenthesis()
{
StringBuilder sb = new StringBuilder("(");
int start = StartIndex;
string token = NextToken();
while (true)
{
if (token == null)
throw new InvalidOperationException("Unable to parse SQL");
sb.Append(token);
if (token == ")" && !Quoted) break;
token = NextToken();
}
return sb.ToString();
}
private bool ReadComment(char c)
{
// make sure the comment starts correctly
if (c == '/' && (Position >= _sql.Length || _sql[Position] != '*')) return false;
if (c == '-' && ((Position + 1) >= _sql.Length || _sql[Position] != '-' || _sql[Position + 1] != ' ')) return false;
string endingPattern = "\n";
if (_sql[Position] == '*')
endingPattern = "*/";
int startingIndex = Position - 1;
int index = _sql.IndexOf(endingPattern, Position);
if (endingPattern == "\n")
index = _sql.IndexOf('\n', Position);
if (index == -1)
index = _sql.Length - 1;
else
index += endingPattern.Length;
Position = index;
if (ReturnComments)
{
StartIndex = startingIndex;
StopIndex = index;
IsComment = true;
}
return true;
}
private void CalculatePosition(int start, int stop)
{
StartIndex = start;
StopIndex = stop;
if (!MultiLine) return;
}
private void ReadUnquotedToken()
{
StartIndex = Position - 1;
if (!IsSpecialCharacter(_sql[StartIndex]))
{
while (Position < _sql.Length)
{
char c = _sql[Position];
if (Char.IsWhiteSpace(c)) break;
if (IsSpecialCharacter(c)) break;
Position++;
}
}
Quoted = false;
StopIndex = Position;
}
private void ReadSpecialToken()
{
StartIndex = Position - 1;
Debug.Assert(IsSpecialCharacter(_sql[StartIndex]));
StopIndex = Position;
Quoted = false;
}
/// <summary>
/// Read a single quoted identifier from the stream
/// </summary>
/// <param name="quoteChar"></param>
/// <returns></returns>
private void ReadQuotedToken(char quoteChar)
{
if (quoteChar == '[')
quoteChar = ']';
StartIndex = Position - 1;
bool escaped = false;
bool found = false;
while (Position < _sql.Length)
{
char c = _sql[Position];
if (c == quoteChar && !escaped)
{
found = true;
break;
}
if (escaped)
escaped = false;
else if (c == '\\' && BackslashEscapes)
escaped = true;
Position++;
}
if (found) Position++;
Quoted = found;
StopIndex = Position;
}
private bool IsQuoteChar(char c)
{
return c == '`' || c == '\'' || c == '\"';
}
private bool IsParameterMarker(char c)
{
return c == '@' || c == '?';
}
private bool IsSpecialCharacter(char c)
{
if (Char.IsLetterOrDigit(c) ||
c == '$' || c == '_' || c == '.') return false;
if (IsParameterMarker(c)) return false;
return true;
}
}
}
#endif