os: fix tests for AIX

This commits fixes tests for AIX inside os package.

"hostname" command on AIX returns "name.domain" and not only "name".
So, "hostname -s" must be called.

Change-Id: I75e193bcb6ad607ce54ad99aabbed9839012f707
Reviewed-on: https://go-review.googlesource.com/c/144537Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/os/executable_test.go

@@ -36,8 +36,8 @@ func TestExecutable(t *testing.T) {
 	// forge argv[0] for child, so that we can verify we could correctly
 	// get real path of the executable without influenced by argv[0].
 	cmd.Args = []string{"-", "-test.run=XXXX"}
-	if runtime.GOOS == "openbsd" {
-		// OpenBSD relies on argv[0]
+	if runtime.GOOS == "openbsd" || runtime.GOOS == "aix" {
+		// OpenBSD and AIX rely on argv[0]
 		cmd.Args[0] = fn
 	}
 	cmd.Env = append(os.Environ(), fmt.Sprintf("%s=1", executable_EnvVar))

src/os/file_posix.go

@@ -7,6 +7,7 @@
 package os
 
 import (
+	"runtime"
 	"syscall"
 	"time"
 )
@@ -19,6 +20,10 @@ func Readlink(name string) (string, error) {
 	for len := 128; ; len *= 2 {
 		b := make([]byte, len)
 		n, e := fixCount(syscall.Readlink(fixLongPath(name), b))
+		// buffer too small
+		if runtime.GOOS == "aix" && e == syscall.ERANGE {
+			continue
+		}
 		if e != nil {
 			return "", &PathError{"readlink", name, e}
 		}

src/os/os_test.go

@@ -1493,7 +1493,11 @@ func runBinHostname(t *testing.T) string {
 	}
 	defer r.Close()
 	const path = "/bin/hostname"
-	p, err := StartProcess(path, []string{"hostname"}, &ProcAttr{Files: []*File{nil, w, Stderr}})
+	argv := []string{"hostname"}
+	if runtime.GOOS == "aix" {
+		argv = []string{"hostname", "-s"}
+	}
+	p, err := StartProcess(path, argv, &ProcAttr{Files: []*File{nil, w, Stderr}})
 	if err != nil {
 		if _, err := Stat(path); IsNotExist(err) {
 			t.Skipf("skipping test; test requires %s but it does not exist", path)

src/os/sticky_bsd.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd netbsd openbsd solaris
+// +build aix darwin dragonfly freebsd netbsd openbsd solaris
 
 package os
 

src/os/sticky_notbsd.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build !aix
 // +build !darwin
 // +build !dragonfly
 // +build !freebsd