func()

in packetbeat/protos/mysql/mysql.go [1001:1148]

• 123 lines of code
• 34 McCabe index (conditional complexity)

func (mysql *mysqlPlugin) parseMysqlResponse(data []byte) ([]string, [][]string) {
	length, err := readLength(data, 0)
	if err != nil {
		logp.Warn("Invalid response: %v", err)
		return []string{}, [][]string{}
	}
	if length < 1 {
		logp.Warn("Warning: Skipping empty Response")
		return []string{}, [][]string{}
	}

	if len(data) < 5 {
		logp.Warn("Invalid response: data less than 5 bytes")
		return []string{}, [][]string{}
	}

	fields := []string{}
	rows := [][]string{}
	switch data[4] {
	case 0x00:
		// OK response
	case 0xff:
		// Error response
	default:
		offset := 5

		logp.Debug("mysql", "Data len: %d", len(data))

		// Read fields
		for {
			length, err = readLength(data, offset)
			if err != nil {
				logp.Warn("Invalid response: %v", err)
				return []string{}, [][]string{}
			}

			if len(data[offset:]) < 5 {
				logp.Warn("Invalid response.")
				return []string{}, [][]string{}
			}

			if data[offset+4] == 0xfe {
				// EOF
				offset += length + 4
				break
			}

			_ /* catalog */, off, complete, err := readLstring(data, offset+4)
			if err != nil || !complete {
				logp.Debug("mysql", "Reading field: %v %v", err, complete)
				return fields, rows
			}
			_ /*database*/, off, complete, err = readLstring(data, off)
			if err != nil || !complete {
				logp.Debug("mysql", "Reading field: %v %v", err, complete)
				return fields, rows
			}
			_ /*table*/, off, complete, err = readLstring(data, off)
			if err != nil || !complete {
				logp.Debug("mysql", "Reading field: %v %v", err, complete)
				return fields, rows
			}
			_ /*org table*/, off, complete, err = readLstring(data, off)
			if err != nil || !complete {
				logp.Debug("mysql", "Reading field: %v %v", err, complete)
				return fields, rows
			}
			name, off, complete, err := readLstring(data, off)
			if err != nil || !complete {
				logp.Debug("mysql", "Reading field: %v %v", err, complete)
				return fields, rows
			}
			_ /* org name */, _ /*off*/, complete, err = readLstring(data, off)
			if err != nil || !complete {
				logp.Debug("mysql", "Reading field: %v %v", err, complete)
				return fields, rows
			}

			fields = append(fields, string(name))

			offset += length + 4
			if len(data) < offset {
				logp.Warn("Invalid response.")
				return []string{}, [][]string{}
			}
		}

		// Read rows
		for offset < len(data) {
			var row []string
			var rowLen int

			if len(data[offset:]) < 5 {
				logp.Warn("Invalid response.")
				break
			}

			if data[offset+4] == 0xfe {
				// EOF
				offset += length + 4 // ineffassign
				break
			}

			length, err = readLength(data, offset)
			if err != nil {
				logp.Warn("Invalid response: %v", err)
				break
			}
			off := offset + 4 // skip length + packet number
			start := off
			for off < start+length {
				var text []byte

				if data[off] == 0xfb {
					text = []byte("NULL")
					off++
				} else {
					var err error
					var complete bool
					text, off, complete, err = readLstring(data, off)
					if err != nil || !complete {
						logp.Debug("mysql", "Error parsing rows: %+v %t", err, complete)
						// nevertheless, return what we have so far
						return fields, rows
					}
				}

				if rowLen < mysql.maxRowLength {
					if rowLen+len(text) > mysql.maxRowLength {
						text = text[:mysql.maxRowLength-rowLen]
					}
					row = append(row, string(text))
					rowLen += len(text)
				}
			}

			logp.Debug("mysqldetailed", "Append row: %v", row)

			rows = append(rows, row)
			if len(rows) >= mysql.maxStoreRows {
				break
			}

			offset += length + 4
		}
	}
	return fields, rows
}