Adding upstream version 1.19.8.upstream/1.19.8upstream

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

1 files changed, 33 insertions, 0 deletions

diff --git a/src/internal/poll/errno_unix.go b/src/internal/poll/errno_unix.go
new file mode 100644
index 0000000..8eed93a
--- /dev/null
+++ b/src/internal/poll/errno_unix.go
@@ -0,0 +1,33 @@
+// Copyright 2019 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 poll
+
+import "syscall"
+
+// Do the interface allocations only once for common
+// Errno values.
+var (
+	errEAGAIN error = syscall.EAGAIN
+	errEINVAL error = syscall.EINVAL
+	errENOENT error = syscall.ENOENT
+)
+
+// errnoErr returns common boxed Errno values, to prevent
+// allocations at runtime.
+func errnoErr(e syscall.Errno) error {
+	switch e {
+	case 0:
+		return nil
+	case syscall.EAGAIN:
+		return errEAGAIN
+	case syscall.EINVAL:
+		return errEINVAL
+	case syscall.ENOENT:
+		return errENOENT
+	}
+	return e
+}