x/sys/unix: fix invalid syscall on linux/arm

Some system calls are obsolete and no longer available for EABI.
This CL replace such system call usages.

Updates golang/go#14524

Change-Id: Ib99b239455ca677e46d7097911904c45119051bd
Reviewed-on: https://go-review.googlesource.com/19945
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

unix/syscall_linux_test.go

@@ -0,0 +1,110 @@
+// Copyright 2016 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.
+
+// +build linux
+
+package unix_test
+
+import (
+	"io/ioutil"
+	"os"
+	"testing"
+	"time"
+
+	"golang.org/x/sys/unix"
+)
+
+func TestTime(t *testing.T) {
+	var ut unix.Time_t
+	ut2, err := unix.Time(&ut)
+	if err != nil {
+		t.Fatalf("Time: %v", err)
+	}
+	if ut != ut2 {
+		t.Errorf("Time: return value %v should be equal to argument %v", ut2, ut)
+	}
+
+	var now time.Time
+
+	for i := 0; i < 10; i++ {
+		ut, err = unix.Time(nil)
+		if err != nil {
+			t.Fatalf("Time: %v", err)
+		}
+
+		now = time.Now()
+
+		if int64(ut) == now.Unix() {
+			return
+		}
+	}
+
+	t.Errorf("Time: return value %v should be nearly equal to time.Now().Unix() %v", ut, now.Unix())
+}
+
+func TestUtime(t *testing.T) {
+	defer chtmpdir(t)()
+
+	touch(t, "file1")
+
+	buf := &unix.Utimbuf{
+		Modtime: 12345,
+	}
+
+	err := unix.Utime("file1", buf)
+	if err != nil {
+		t.Fatalf("Utime: %v", err)
+	}
+
+	fi, err := os.Stat("file1")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if fi.ModTime().Unix() != 12345 {
+		t.Errorf("Utime: failed to change modtime: expected %v, got %v", 12345, fi.ModTime().Unix())
+	}
+}
+
+func TestGetrlimit(t *testing.T) {
+	var rlim unix.Rlimit
+	err := unix.Getrlimit(unix.RLIMIT_AS, &rlim)
+	if err != nil {
+		t.Fatalf("Getrlimit: %v", err)
+	}
+}
+
+// utilities taken from os/os_test.go
+
+func touch(t *testing.T, name string) {
+	f, err := os.Create(name)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := f.Close(); err != nil {
+		t.Fatal(err)
+	}
+}
+
+// chtmpdir changes the working directory to a new temporary directory and
+// provides a cleanup function. Used when PWD is read-only.
+func chtmpdir(t *testing.T) func() {
+	oldwd, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("chtmpdir: %v", err)
+	}
+	d, err := ioutil.TempDir("", "test")
+	if err != nil {
+		t.Fatalf("chtmpdir: %v", err)
+	}
+	if err := os.Chdir(d); err != nil {
+		t.Fatalf("chtmpdir: %v", err)
+	}
+	return func() {
+		if err := os.Chdir(oldwd); err != nil {
+			t.Fatalf("chtmpdir: %v", err)
+		}
+		os.RemoveAll(d)
+	}
+}