From ea6b397526ee830cd43beb11200b0c206d654c2d Mon Sep 17 00:00:00 2001
From: xushiwei <x@goplus.org>
Date: Fri, 19 Jul 2024 22:23:12 +0800
Subject: [PATCH] library: os/exec.Cmd.childStdin

---
 internal/lib/os/exec/exec.go         |  3 ---
 internal/lib/os/exec/exec_plan9.go   | 19 +++++++++++++++++++
 internal/lib/os/exec/exec_unix.go    | 24 ++++++++++++++++++++++++
 internal/lib/os/exec/exec_windows.go | 23 +++++++++++++++++++++++
 4 files changed, 66 insertions(+), 3 deletions(-)
 create mode 100644 internal/lib/os/exec/exec_plan9.go
 create mode 100644 internal/lib/os/exec/exec_unix.go
 create mode 100644 internal/lib/os/exec/exec_windows.go

diff --git a/internal/lib/os/exec/exec.go b/internal/lib/os/exec/exec.go
index d56db4e7..c54ecc3e 100644
--- a/internal/lib/os/exec/exec.go
+++ b/internal/lib/os/exec/exec.go
@@ -416,7 +416,6 @@ func (c *Cmd) argv() []string {
 }
 
 func (c *Cmd) childStdin() (*os.File, error) {
-	/* TODO(xsw):
 	if c.Stdin == nil {
 		f, err := os.Open(os.DevNull)
 		if err != nil {
@@ -448,8 +447,6 @@ func (c *Cmd) childStdin() (*os.File, error) {
 		return err
 	})
 	return pr, nil
-	*/
-	panic("todo: exec.Cmd.childStdin")
 }
 
 func (c *Cmd) childStdout() (*os.File, error) {
diff --git a/internal/lib/os/exec/exec_plan9.go b/internal/lib/os/exec/exec_plan9.go
new file mode 100644
index 00000000..8920bec1
--- /dev/null
+++ b/internal/lib/os/exec/exec_plan9.go
@@ -0,0 +1,19 @@
+// 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.
+
+package exec
+
+import "io/fs"
+
+// skipStdinCopyError optionally specifies a function which reports
+// whether the provided stdin copy error should be ignored.
+func skipStdinCopyError(err error) bool {
+	// Ignore hungup errors copying to stdin if the program
+	// completed successfully otherwise.
+	// See Issue 35753.
+	pe, ok := err.(*fs.PathError)
+	return ok &&
+		pe.Op == "write" && pe.Path == "|1" &&
+		pe.Err.Error() == "i/o on hungup channel"
+}
diff --git a/internal/lib/os/exec/exec_unix.go b/internal/lib/os/exec/exec_unix.go
new file mode 100644
index 00000000..3ed672a7
--- /dev/null
+++ b/internal/lib/os/exec/exec_unix.go
@@ -0,0 +1,24 @@
+// Copyright 2015 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 !plan9 && !windows
+
+package exec
+
+import (
+	"io/fs"
+	"syscall"
+)
+
+// skipStdinCopyError optionally specifies a function which reports
+// whether the provided stdin copy error should be ignored.
+func skipStdinCopyError(err error) bool {
+	// Ignore EPIPE errors copying to stdin if the program
+	// completed successfully otherwise.
+	// See Issue 9173.
+	pe, ok := err.(*fs.PathError)
+	return ok &&
+		pe.Op == "write" && pe.Path == "|1" &&
+		pe.Err == syscall.EPIPE
+}
diff --git a/internal/lib/os/exec/exec_windows.go b/internal/lib/os/exec/exec_windows.go
new file mode 100644
index 00000000..e7a2ee6c
--- /dev/null
+++ b/internal/lib/os/exec/exec_windows.go
@@ -0,0 +1,23 @@
+// Copyright 2017 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.
+
+package exec
+
+import (
+	"io/fs"
+	"syscall"
+)
+
+// skipStdinCopyError optionally specifies a function which reports
+// whether the provided stdin copy error should be ignored.
+func skipStdinCopyError(err error) bool {
+	// Ignore ERROR_BROKEN_PIPE and ERROR_NO_DATA errors copying
+	// to stdin if the program completed successfully otherwise.
+	// See Issue 20445.
+	const _ERROR_NO_DATA = syscall.Errno(0xe8)
+	pe, ok := err.(*fs.PathError)
+	return ok &&
+		pe.Op == "write" && pe.Path == "|1" &&
+		(pe.Err == syscall.ERROR_BROKEN_PIPE || pe.Err == _ERROR_NO_DATA)
+}