Function NewPDFReader

cmd/pdftext/reader.go:32–74

(reader io.Reader, password string)

}

func NewPDFReader(reader io.Reader, password string) (*pdfReader, error) {
	data, err := io.ReadAll(reader)
	if err != nil {
		return nil, err
	} else if len(data) < 8 || !bytes.Equal(data[:7], []byte("%PDF-1.")) || data[7] < '0' || '7' < data[7] {
		return nil, fmt.Errorf("invalid PDF file: bad version")
	}

	r := &pdfReader{
		data:    data,
		objects: map[pdfRef]pdfObject{},
		cache:   map[pdfRef]any{},
	}

	// get startxref
	var line []byte
	lrr := newLineReaderReverse(r.data, len(r.data))
	if line = lrr.Next(); !bytes.Equal(line, []byte("%%EOF")) {
		return nil, fmt.Errorf("invalid PDF file")
	}
	if r.data[lrr.Pos()] == '\r' && r.data[lrr.Pos()+1] == '\n' {
		r.eol = r.data[lrr.Pos() : lrr.Pos()+2]
	} else {
		r.eol = r.data[lrr.Pos() : lrr.Pos()+1]
	}
	num, _ := strconv.ParseUint(lrr.Next())
	if num == 0 {
		return nil, fmt.Errorf("invalid PDF file")
	} else if line = lrr.Next(); !bytes.Equal(bytes.TrimSpace(line), []byte("startxref")) {
		return nil, fmt.Errorf("invalid PDF file")
	}
	startxref := int(num)
	//endtrailer := lrr.Pos()

	if r.trailer, err = r.readTrailer(startxref); err != nil {
		return nil, err
	} else if err := r.readEncrypt([]byte(password)); err != nil {
		return nil, err
	} else if err := r.readKids(); err != nil {
		return nil, err
	}
	return r, nil
}

func (r *pdfReader) readCrossReferenceTable() (pdfDict, error) {
	var starttrailer int