Adding upstream version 1.22.1.upstream/1.22.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/src/runtime/retry.go b/src/runtime/retry.go
new file mode 100644
index 0000000..2e2f813
--- /dev/null
+++ b/src/runtime/retry.go
@@ -0,0 +1,23 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package runtime
+
+// retryOnEAGAIN retries a function until it does not return EAGAIN.
+// It will use an increasing delay between calls, and retry up to 20 times.
+// The function argument is expected to return an errno value,
+// and retryOnEAGAIN will return any errno value other than EAGAIN.
+// If all retries return EAGAIN, then retryOnEAGAIN will return EAGAIN.
+func retryOnEAGAIN(fn func() int32) int32 {
+	for tries := 0; tries < 20; tries++ {
+		errno := fn()
+		if errno != _EAGAIN {
+			return errno
+		}
+		usleep_no_g(uint32(tries+1) * 1000) // milliseconds
+	}
+	return _EAGAIN
+}