/// <summary>
        /// Create Trans2FindFirst2 request for the client to find file on server. 
        /// </summary>
        /// <param name = "treeId">the valid tree connect id, must be response by server of the tree connect. </param>
        /// <param name = "fileName">The file name to find. </param>
        /// <param name = "transactOptions">
        /// A set of bit flags that alter the behavior of the requested operation. Unused bit fields MUST be set to  
        /// zero by the client sending the request, and MUST be ignored by the server receiving the request. The 
        /// client MAY set either or both of the following bit flags 
        /// </param>
        /// <param name = "searchCount">
        /// The server MUST NOT return more entries than indicated by the value of this field. 
        /// </param>
        /// <param name = "findFlags">
        /// This 16-bit field of flags is used to request that the server take certain actions. 
        /// </param>
        /// <param name = "searchAttributes">File attributes to apply as a constraint to the file search. </param>
        /// <param name = "searchStorageType">
        /// This field specifies if the find is searching for directories or for files. This field MUST be one of two  
        /// values 
        /// </param>
        /// <param name = "isReparsePath">If true, the path in the request MUST contain an @GMT token. </param>
        /// <param name = "isKnowsLongName">
        /// is used to indicate to set the SMB_FLAGS2_KNOWS_LONG_NAMES flag in smb header or not. 
        /// </param>
        /// <param name = "informationLevel">
        /// Indicates that client specifies the information it is requesting. Server return different data based on 
        /// the client's request. 
        /// </param>
        /// <returns>a find file for the first request packet </returns>
        public virtual SmbTrans2FindFirst2RequestPacket CreateTrans2FindFirst2Request(
            ushort treeId,
            string fileName,
            Trans2SmbParametersFlags transactOptions,
            ushort searchCount,
            Trans2FindFlags findFlags,
            SmbFileAttributes searchAttributes,
            Trans2FindFirst2SearchStorageType searchStorageType,
            bool isReparsePath,
            bool isKnowsLongName,
            FindInformationLevel informationLevel)
        {
            SmbHeader_Flags2_Values flags2 = this.capability.Flags2;
            // update flags2 of header
            if (isReparsePath)
            {
                flags2 |= SmbHeader_Flags2_Values.SMB_FLAGS2_REPARSE_PATH;
            }

            if (isKnowsLongName)
            {
                flags2 |= SmbHeader_Flags2_Values.SMB_FLAGS2_KNOWS_LONG_NAMES;
            }
            return CreateTrans2FindFirst2Request(this.MessageId,
                this.GetSessionIdByTreeId(treeId), treeId,
               this.capability.Flag, flags2, fileName, transactOptions,
                this.capability.Timeout, searchCount, findFlags, searchAttributes, searchStorageType,
                informationLevel);
        }
 /// <summary>
 /// to create a Trans2FindFirst2 request packet.
 /// </summary>
 /// <param name="uid">This field SHOULD identify the authenticated instance of the user.</param>
 /// <param name="treeId">This field identifies the subdirectory (or tree) on the server that the client is
 /// accessing.</param>
 /// <param name="extendedAttributeList">A list of extended file attribute name/value pairs. </param>
 /// <param name="searchCount">The server MUST NOT return more entries than indicated by the value of this
 /// field.</param>
 /// <param name="searchAttributes">File attributes to apply as a constraint to the file search.</param>
 /// <param name="findFlags">This 16-bit field of flags is used to request that the server take
 /// certain actions.</param>
 /// <param name="informationLevel">This field contains an information level code, which determines the
 /// information contained in the response.</param>
 /// <param name="searchStorageType">This field specifies if the find is searching for directories or for files.
 /// This field MUST be one of two values</param>
 /// <param name="name">A buffer containing the name of the file to be opened, created, or truncated. The
 /// string MUST be null terminated</param>
 /// <returns>a Trans2FindFirst2 request packet</returns>
 /// <exception cref="System.NullReferenceException">There is no connection in context. </exception>
 public SmbTrans2FindFirst2RequestPacket CreateTrans2FindFirst2Request(
     ushort uid,
     ushort treeId,
     SmbFileAttributes searchAttributes,
     Trans2FindFlags findFlags,
     ushort searchCount,
     FindInformationLevel informationLevel,
     Trans2FindFirst2SearchStorageType searchStorageType,
     string name,
     SMB_GEA[] extendedAttributeList)
 {
     return this.CreateTrans2FindFirst2Request(this.Context.GetMessageId(this.connectionId),
         uid, treeId, this.defaultParameters.Flag, this.defaultParameters.Flag2, this.defaultParameters.MaxParameterCount,
         this.defaultParameters.MaxDataCount, this.defaultParameters.MaxSetupCount, this.defaultParameters.Trans2SmbParametersFlags,
         this.defaultParameters.Timeout, searchAttributes, searchCount, findFlags, informationLevel,
         searchStorageType, name, extendedAttributeList);
 }
 /// <summary>
 /// Create Trans2FindFirst2 request for the client to find file on server. 
 /// </summary>
 /// <param name = "messageId">the id of message, used to identity the request and the server response. </param>
 /// <param name = "sessionUid">the valid session id, must be response by server of the session setup request. </param>
 /// <param name = "treeId">the valid tree connect id, must be response by server of the tree connect. </param>
 /// <param name = "flags">
 /// The Flags field contains individual flags, as specified in [CIFS] sections 2.4.2 and 3.1.1. 
 /// </param>
 /// <param name = "flags2">
 /// The Flags2 field contains individual bit flags that, depending on the negotiated SMB dialect, indicate   
 /// various client and server capabilities. 
 /// </param>
 /// <param name = "fileName">The file name to find. </param>
 /// <param name = "transactOptions">
 /// A set of bit flags that alter the behavior of the requested operation. Unused bit fields MUST be set to  
 /// zero by the client sending the request, and MUST be ignored by the server receiving the request. The 
 /// client MAY set either or both of the following bit flags 
 /// </param>
 /// <param name = "timeOut">
 /// The maximum amount of time in milliseconds to wait for the operation to complete. The client SHOULD set  
 /// this to 0 to indicate that no time-out is given. If the operation does not complete within the specified  
 /// time, the server MAY abort the request and send a failure response. 
 /// </param>
 /// <param name = "searchCount">
 /// The server MUST NOT return more entries than indicated by the value of this field. 
 /// </param>
 /// <param name = "findFlags">
 /// This 16-bit field of flags is used to request that the server take certain actions. 
 /// </param>
 /// <param name = "searchAttributes">File attributes to apply as a constraint to the file search. </param>
 /// <param name = "searchStorageType">
 /// This field specifies if the find is searching for directories or for files.This field MUST be one of two  
 /// values 
 /// </param>
 /// <param name = "informationLevel">
 /// Indicates that client specifies the information it is requesting. Server return different data based on 
 /// the client's request. 
 /// </param>
 /// <returns>a find file for the first request packet </returns>
 private SmbTrans2FindFirst2RequestPacket CreateTrans2FindFirst2Request(
     ushort messageId,
     ushort sessionUid,
     ushort treeId,
     SmbHeader_Flags_Values flags,
     SmbHeader_Flags2_Values flags2,
     string fileName,
     Trans2SmbParametersFlags transactOptions,
     uint timeOut,
     ushort searchCount,
     Trans2FindFlags findFlags,
     SmbFileAttributes searchAttributes,
     Trans2FindFirst2SearchStorageType searchStorageType,
     FindInformationLevel informationLevel)
 {
     return new SmbTrans2FindFirst2RequestPacket(
         this.cifsClient.CreateTrans2FindFirst2Request(
         messageId, sessionUid, treeId, (SmbFlags)flags, (SmbFlags2)flags2,
         this.capability.MaxParameterCount, this.capability.MaxDataCount, this.capability.MaxSetupCount,
         transactOptions, timeOut, searchAttributes, searchCount,
         findFlags, (Cifs.FindInformationLevel)informationLevel, searchStorageType, fileName, null));
 }
        /// <summary>
        /// to create a Trans2FindFirst2 request packet.
        /// </summary>
        /// <param name="messageId">This field SHOULD be the multiplex ID that is used to associate a response with a
        /// request.</param>
        /// <param name="uid">This field SHOULD identify the authenticated instance of the user.</param>
        /// <param name="treeId">This field identifies the subdirectory (or tree) on the server that the client is
        /// accessing.</param>
        /// <param name="flags">An 8-bit field of 1-bit flags describing various features in effect for the
        /// message</param>
        /// <param name="flags2">A 16-bit field of 1-bit flags that represent various features in effect for the
        /// message. Unspecified bits are reserved and MUST be zero.</param>
        /// <param name="maxParameterCount">The maximum number of parameter bytes that the client will accept in the
        /// transaction reply. The server MUST NOT return more than this number of parameter bytes.</param>
        /// <param name="maxDataCount">The maximum number of data bytes that the client will accept in the transaction
        /// reply. The server MUST NOT return more than this number of data bytes.</param>
        /// <param name="maxSetupCount">Maximum number of setup bytes that the client will accept in the transaction
        /// reply. The server MUST NOT return more than this number of setup bytes</param>
        /// <param name="smbParametersFlags">A set of bit flags that alter the behavior of the requested operation.
        /// Unused bit fields MUST be set to zero by the client sending the request, and MUST be ignored by the server
        /// receiving the request. The client MAY set either or both of the following bit flags</param>
        /// <param name="timeout">The number of milliseconds the server SHOULD wait for completion of the transaction
        /// before generating a timeout. A value of zero indicates that the operation MUST NOT block.</param>
        /// <param name="extendedAttributeList">A list of extended file attribute name/value pairs. </param>
        /// <param name="searchCount">The server MUST NOT return more entries than indicated by the value of this
        /// field.</param>
        /// <param name="searchAttributes">File attributes to apply as a constraint to the file search.</param>
        /// <param name="informationLevel">This field contains an information level code, which determines the
        /// information contained in the response.</param>
        /// <param name="searchStorageType">This field specifies if the find is searching for directories or for files.
        /// This field MUST be one of two values</param>
        /// <param name="name">A buffer containing the name of the file to be opened, created, or truncated. The
        /// string MUST be null terminated</param>
        /// <param name="findFlags">This 16-bit field of flags is used to request that the server take
        /// certain actions.</param>
        /// <returns>a Trans2FindFirst2 request packet</returns>
        public SmbTrans2FindFirst2RequestPacket CreateTrans2FindFirst2Request(
            ushort messageId,
            ushort uid,
            ushort treeId,
            SmbFlags flags,
            SmbFlags2 flags2,
            ushort maxParameterCount,
            ushort maxDataCount,
            byte maxSetupCount,
            Trans2SmbParametersFlags smbParametersFlags,
            uint timeout,
            SmbFileAttributes searchAttributes,
            ushort searchCount,
            Trans2FindFlags findFlags,
            FindInformationLevel informationLevel,
            Trans2FindFirst2SearchStorageType searchStorageType,
            string name,
            SMB_GEA[] extendedAttributeList)
        {
            if (name == null)
            {
                name = string.Empty;
            }
            if (extendedAttributeList == null)
            {
                extendedAttributeList = new SMB_GEA[0];
            }

            SmbTrans2FindFirst2RequestPacket packet = new SmbTrans2FindFirst2RequestPacket();

            packet.SmbHeader = CifsMessageUtils.CreateSmbHeader(SmbCommand.SMB_COM_TRANSACTION2,
                messageId, uid, treeId, flags, flags2);

            // Set Smb_Parameters
            SMB_COM_TRANSACTION2_Request_SMB_Parameters smbParameters =
                new SMB_COM_TRANSACTION2_Request_SMB_Parameters();
            smbParameters.MaxParameterCount = maxParameterCount;
            smbParameters.MaxDataCount = maxDataCount;
            smbParameters.MaxSetupCount = maxSetupCount;
            smbParameters.Flags = (ushort)smbParametersFlags;
            smbParameters.Timeout = timeout;
            smbParameters.SetupCount = 1; // the correct count in word of the Setup is always 1.
            smbParameters.Setup = new ushort[] { (ushort)Trans2SubCommand.TRANS2_FIND_FIRST2 };
            smbParameters.WordCount = (byte)(CifsMessageUtils.GetSize<SMB_COM_TRANSACTION2_Request_SMB_Parameters>(
                smbParameters) / NumBytesOfWord);

            // Set Smb_Data
            SMB_COM_TRANSACTION2_Request_SMB_Data smbData = new SMB_COM_TRANSACTION2_Request_SMB_Data();
            smbData.Name = CifsMessageUtils.ToSmbStringBytes(name,
                (flags2 & SmbFlags2.SMB_FLAGS2_UNICODE) == SmbFlags2.SMB_FLAGS2_UNICODE);

            // The size of the preceding SmbParameters part plus Header part is an odd number for all cifs messages
            // Use Name field to judge whether needs to add one 16-bits align pad.
            if ((flags2 & SmbFlags2.SMB_FLAGS2_UNICODE) == SmbFlags2.SMB_FLAGS2_UNICODE && smbData.Name.Length
                % twoBytesAlign == 0)
            {
                // pad 1 byte for 16-bits align:
                smbData.Pad1 = new byte[1];
            }
            else
            {
                smbData.Pad1 = new byte[0];
            }

            // Set Trans2_Parameters
            TRANS2_FIND_FIRST2_Request_Trans2_Parameters trans2Parameters =
                new TRANS2_FIND_FIRST2_Request_Trans2_Parameters();
            trans2Parameters.SearchAttributes = searchAttributes;
            trans2Parameters.SearchCount = searchCount;
            trans2Parameters.Flags = findFlags;
            trans2Parameters.InformationLevel = informationLevel;
            trans2Parameters.SearchStorageType = searchStorageType;
            trans2Parameters.FileName = CifsMessageUtils.ToSmbStringBytes(name,
                (flags2 & SmbFlags2.SMB_FLAGS2_UNICODE) == SmbFlags2.SMB_FLAGS2_UNICODE);

            // Set Trans2_Data
            TRANS2_FIND_FIRST2_Request_Trans2_Data trans2Data = new TRANS2_FIND_FIRST2_Request_Trans2_Data();
            trans2Data.GetExtendedAttributeList.GEAList = extendedAttributeList;
            trans2Data.GetExtendedAttributeList.SizeOfListInBytes =
                (uint)CifsMessageUtils.GetSize<uint>(trans2Data.GetExtendedAttributeList.SizeOfListInBytes);
            trans2Data.GetExtendedAttributeList.SizeOfListInBytes +=
                CifsMessageUtils.GetSmbQueryEAListSize(extendedAttributeList);

            packet.SmbParameters = smbParameters;
            packet.SmbData = smbData;
            packet.Trans2Parameters = trans2Parameters;
            packet.Trans2Data = trans2Data;
            packet.UpdateCountAndOffset();

            return packet;
        }