| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package functions |
| 4 | |
| 5 | import ( |
| 6 | "bufio" |
| 7 | "os" |
| 8 | "sync" |
| 9 | ) |
| 10 | |
| 11 | type input interface { |
| 12 | lines() <-chan string |
| 13 | } |
| 14 | |
| 15 | func newStdinInput() input { |
| 16 | return &stdinReader{} |
| 17 | } |
| 18 | |
| 19 | type stdinReader struct { |
| 20 | once sync.Once |
| 21 | linesCh chan string |
| 22 | } |
| 23 | |
| 24 | func (in *stdinReader) run() { |
| 25 | defer close(in.linesCh) |
| 26 | sc := bufio.NewScanner(bufio.NewReader(os.Stdin)) |
| 27 | |
| 28 | for sc.Scan() { |
| 29 | in.linesCh <- sc.Text() |
| 30 | } |
| 31 | } |
| 32 | |
| 33 | func (in *stdinReader) lines() <-chan string { |
| 34 | in.once.Do(func() { |
| 35 | in.linesCh = make(chan string) |
| 36 | go in.run() |
| 37 | }) |
| 38 | |
| 39 | return in.linesCh |
| 40 | } |