// Copyright (c) 2015-2021 MinIO, Inc.//// This file is part of MinIO Object Storage stack//// This program is free software: you can redistribute it and/or modify// it under the terms of the GNU Affero General Public License as published by// the Free Software Foundation, either version 3 of the License, or// (at your option) any later version.//// 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 Affero General Public License for more details.//// You should have received a copy of the GNU Affero General Public License// along with this program.  If not, see <http://www.gnu.org/licenses/>. package csv import (	"encoding/xml"	"errors"	"fmt"	"io"	"strings"	"unicode/utf8") const (	none = "none"	use  = "use" 	defaultRecordDelimiter      = "\n"	defaultFieldDelimiter       = ","	defaultQuoteCharacter       = `"`	defaultQuoteEscapeCharacter = `"`	defaultCommentCharacter     = "#" 	asneeded = "asneeded") // ReaderArgs - represents elements inside <InputSerialization><CSV> in request XML.type ReaderArgs struct {	FileHeaderInfo             string `xml:"FileHeaderInfo"`	RecordDelimiter            string `xml:"RecordDelimiter"`	FieldDelimiter             string `xml:"FieldDelimiter"`	QuoteCharacter             string `xml:"QuoteCharacter"`	QuoteEscapeCharacter       string `xml:"QuoteEscapeCharacter"`	CommentCharacter           string `xml:"Comments"`	AllowQuotedRecordDelimiter bool   `xml:"AllowQuotedRecordDelimiter"`	unmarshaled                bool} // IsEmpty - returns whether reader args is empty or not.func (args *ReaderArgs) IsEmpty() bool {	return !args.unmarshaled} // UnmarshalXML - decodes XML data.func (args *ReaderArgs) UnmarshalXML(d *xml.Decoder, start xml.StartElement) (err error) {	args.FileHeaderInfo = none	args.RecordDelimiter = defaultRecordDelimiter	args.FieldDelimiter = defaultFieldDelimiter	args.QuoteCharacter = defaultQuoteCharacter	args.QuoteEscapeCharacter = defaultQuoteEscapeCharacter	args.CommentCharacter = defaultCommentCharacter	args.AllowQuotedRecordDelimiter = false 	for {		// Read tokens from the XML document in a stream.		t, err := d.Token()		if err != nil {			if err == io.EOF {				break			}			return err		} 		switch se := t.(type) {		case xml.StartElement:			tagName := se.Name.Local			switch tagName {			case "AllowQuotedRecordDelimiter":				var b bool				if err = d.DecodeElement(&b, &se); err != nil {					return err				}				args.AllowQuotedRecordDelimiter = b			default:				var s string				if err = d.DecodeElement(&s, &se); err != nil {					return err				}				switch tagName {				case "FileHeaderInfo":					args.FileHeaderInfo = strings.ToLower(s)				case "RecordDelimiter":					args.RecordDelimiter = s				case "FieldDelimiter":					args.FieldDelimiter = s				case "QuoteCharacter":					if utf8.RuneCountInString(s) > 1 {						return fmt.Errorf("unsupported QuoteCharacter '%v'", s)					}					args.QuoteCharacter = s				case "QuoteEscapeCharacter":					switch utf8.RuneCountInString(s) {					case 0:						args.QuoteEscapeCharacter = defaultQuoteEscapeCharacter					case 1:						args.QuoteEscapeCharacter = s					default:						return fmt.Errorf("unsupported QuoteEscapeCharacter '%v'", s)					}				case "Comments":					args.CommentCharacter = s				default:					return errors.New("unrecognized option")				}			}		}	} 	args.unmarshaled = true	return nil} // WriterArgs - represents elements inside <OutputSerialization><CSV/> in request XML.type WriterArgs struct {	QuoteFields          string `xml:"QuoteFields"`	RecordDelimiter      string `xml:"RecordDelimiter"`	FieldDelimiter       string `xml:"FieldDelimiter"`	QuoteCharacter       string `xml:"QuoteCharacter"`	QuoteEscapeCharacter string `xml:"QuoteEscapeCharacter"`	unmarshaled          bool} // IsEmpty - returns whether writer args is empty or not.func (args *WriterArgs) IsEmpty() bool {	return !args.unmarshaled} // UnmarshalXML - decodes XML data.func (args *WriterArgs) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {	args.QuoteFields = asneeded	args.RecordDelimiter = defaultRecordDelimiter	args.FieldDelimiter = defaultFieldDelimiter	args.QuoteCharacter = defaultQuoteCharacter	args.QuoteEscapeCharacter = defaultQuoteCharacter 	for {		// Read tokens from the XML document in a stream.		t, err := d.Token()		if err != nil {			if err == io.EOF {				break			}			return err		} 		switch se := t.(type) {		case xml.StartElement:			var s string			if err = d.DecodeElement(&s, &se); err != nil {				return err			}			switch se.Name.Local {			case "QuoteFields":				args.QuoteFields = strings.ToLower(s)			case "RecordDelimiter":				args.RecordDelimiter = s			case "FieldDelimiter":				args.FieldDelimiter = s			case "QuoteCharacter":				switch utf8.RuneCountInString(s) {				case 0:					args.QuoteCharacter = "\x00"				case 1:					args.QuoteCharacter = s				default:					return fmt.Errorf("unsupported QuoteCharacter '%v'", s)				}			case "QuoteEscapeCharacter":				switch utf8.RuneCountInString(s) {				case 0:					args.QuoteEscapeCharacter = defaultQuoteEscapeCharacter				case 1:					args.QuoteEscapeCharacter = s				default:					return fmt.Errorf("unsupported QuoteCharacter '%v'", s)				}			default:				return errors.New("unrecognized option")			}		}	} 	args.unmarshaled = true	return nil}