Adding upstream version 1.21.8.upstream/1.21.8

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

1 files changed, 53 insertions, 0 deletions

diff --git a/src/os/sys_linux.go b/src/os/sys_linux.go
new file mode 100644
index 0000000..36a8a24
--- /dev/null
+++ b/src/os/sys_linux.go
@@ -0,0 +1,53 @@
+// Copyright 2009 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 os
+
+import (
+	"runtime"
+	"syscall"
+)
+
+func hostname() (name string, err error) {
+	// Try uname first, as it's only one system call and reading
+	// from /proc is not allowed on Android.
+	var un syscall.Utsname
+	err = syscall.Uname(&un)
+
+	var buf [512]byte // Enough for a DNS name.
+	for i, b := range un.Nodename[:] {
+		buf[i] = uint8(b)
+		if b == 0 {
+			name = string(buf[:i])
+			break
+		}
+	}
+	// If we got a name and it's not potentially truncated
+	// (Nodename is 65 bytes), return it.
+	if err == nil && len(name) > 0 && len(name) < 64 {
+		return name, nil
+	}
+	if runtime.GOOS == "android" {
+		if name != "" {
+			return name, nil
+		}
+		return "localhost", nil
+	}
+
+	f, err := Open("/proc/sys/kernel/hostname")
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	n, err := f.Read(buf[:])
+	if err != nil {
+		return "", err
+	}
+
+	if n > 0 && buf[n-1] == '\n' {
+		n--
+	}
+	return string(buf[:n]), nil
+}