Function loadPipeToBuffer

io.go:634–729

load console pipe content to buffer (synchronous version)

(stdin io.Reader, b *Buffer)

// load console pipe content to buffer (synchronous version)
func loadPipeToBuffer(stdin io.Reader, b *Buffer) error {
	totalAddedLN := 0 //the number of lines has been added into buffer
	var err error

	// Create progress tracker (no file size for pipes)
	progress := newProgressTracker(0, true)

	scanner := bufio.NewScanner(stdin)
	//increase buffer size for large files and long lines
	const maxScanTokenSize = 1024 * 1024
	buf := make([]byte, maxScanTokenSize)
	scanner.Buffer(buf, maxScanTokenSize)
	//read 10 lines to detect separator
	lineNumber := 10
	var detectLines []string //lines as detect separator data
	if b.sep == 0 {
		for scanner.Scan() {
			line := scanner.Text()
			//skip empty line
			if line == "\n" {
				continue
			}
			//ignore first n lines
			if args.SkipNum > 0 {
				args.SkipNum--
				continue
			}
			//ignore line with specified prefix
			if skipLine(line, args.SkipSymbol) {
				continue
			}
			detectLines = append(detectLines, line)
			if len(detectLines) >= lineNumber {
				break
			}
		}
		sd := sepDetecor{}
		b.sep = sd.sepDetect(detectLines)
	}
	//check final separator
	if b.sep == 0 {
		fatalError(errors.New("tv can't identify separator, you need to set it manual"))
	}

	//add detectLines to buffer
	for _, line := range detectLines {
		//parse and add line to buffer
		err = addDRToBuffer(b, line, args.ShowNum, args.HideNum)
		if err != nil {
			progress.finish()
			return err
		}
		totalAddedLN++
		progress.increment(int64(len(line) + 1))
		if totalAddedLN >= args.NLine && args.NLine > 0 {
			break
		}
	}