| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package scrape |
| 4 | |
| 5 | import "sync" |
| 6 | |
| 7 | type throttledCaller struct { |
| 8 | limit chan struct{} |
| 9 | wg sync.WaitGroup |
| 10 | } |
| 11 | |
| 12 | func newThrottledCaller(limit int) *throttledCaller { |
| 13 | if limit <= 0 { |
| 14 | panic("limit must be > 0") |
| 15 | } |
| 16 | return &throttledCaller{limit: make(chan struct{}, limit)} |
| 17 | } |
| 18 | |
| 19 | func (t *throttledCaller) call(job func()) { |
| 20 | t.wg.Go(func() { |
| 21 | t.limit <- struct{}{} |
| 22 | defer func() { |
| 23 | <-t.limit |
| 24 | }() |
| 25 | job() |
| 26 | }) |
| 27 | } |
| 28 | |
| 29 | func (t *throttledCaller) wait() { |
| 30 | t.wg.Wait() |
| 31 | } |