1// Copyright 2017 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package unix_test
6
7import (
8	"fmt"
9	"testing"
10
11	"golang.org/x/sys/unix"
12)
13
14func TestDevices(t *testing.T) {
15	testCases := []struct {
16		path  string
17		major uint32
18		minor uint32
19	}{
20		// well known major/minor numbers according to
21		// https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-guide/devices.txt
22		{"/dev/null", 1, 3},
23		{"/dev/zero", 1, 5},
24		{"/dev/random", 1, 8},
25		{"/dev/full", 1, 7},
26		{"/dev/urandom", 1, 9},
27		{"/dev/tty", 5, 0},
28	}
29	for _, tc := range testCases {
30		t.Run(fmt.Sprintf("%s %v:%v", tc.path, tc.major, tc.minor), func(t *testing.T) {
31			var stat unix.Stat_t
32			err := unix.Stat(tc.path, &stat)
33			if err != nil {
34				t.Errorf("failed to stat device: %v", err)
35				return
36			}
37
38			dev := uint64(stat.Rdev)
39			if unix.Major(dev) != tc.major {
40				t.Errorf("for %s Major(%#x) == %d, want %d", tc.path, dev, unix.Major(dev), tc.major)
41			}
42			if unix.Minor(dev) != tc.minor {
43				t.Errorf("for %s Minor(%#x) == %d, want %d", tc.path, dev, unix.Minor(dev), tc.minor)
44			}
45			if unix.Mkdev(tc.major, tc.minor) != dev {
46				t.Errorf("for %s Mkdev(%d, %d) == %#x, want %#x", tc.path, tc.major, tc.minor, unix.Mkdev(tc.major, tc.minor), dev)
47			}
48		})
49
50	}
51}
52