tests: add v0.9 example filesystem with a 255-byte filename

gocryptfs v0.9 introduced long file names, so lets add an
example filesystem that has that feature flag set.

Operations on long file names are tested in the regular integration
tests as well.

integration_tests/example_filesystems/v0.9/00msNUi5h5aKMX_f-4pBhA==

@@ -0,0 +1 @@
+5nI119EbCRtgT8AwTDPmxCuORvbGV4xdtmqnur7KK9ufir-ALyneV7Iy

integration_tests/example_filesystems/v0.9/gocryptfs.conf

@@ -0,0 +1,17 @@
+{
+	"EncryptedKey": "sAB/dsiDbFBbMr7ppsB3Fu81hVr6BBxlcfY1wZYRHlRvRV2uwRdYAACNM39CDxLBHZuNjk9UyWh87McP",
+	"ScryptObject": {
+		"Salt": "3mphl9Hmhzd6exmc8Um0jOOCgR8hAYvbzbEpTnIEMPg=",
+		"N": 1024,
+		"R": 8,
+		"P": 1,
+		"KeyLen": 32
+	},
+	"Version": 2,
+	"FeatureFlags": [
+		"GCMIV128",
+		"DirIV",
+		"EMENames",
+		"LongNames"
+	]
+}

integration_tests/example_filesystems/v0.9/gocryptfs.diriv

@@ -0,0 +1 @@
+˙~HŐćá‡A|Ô<>Čă­

integration_tests/example_filesystems/v0.9/gocryptfs.longname.y4J-w3LBX165Mn_pGdDRY7Gb6EgHcTrdWjME3WGu-CQ=.name

@@ -0,0 +1 @@
+Py7wkyXYf1YXvFvHuizOqva6WWWYEQ-JYv1rOAvWWaARLyGdQdxuW-iBf1Vwd8orZjqkcIGgnxOfuRsarXKmn4-3L2MRIZKPhhx2QRqpPRtFylEABH1KwZ_2ZZnx5cpcO8TIoeVdL6NXnRw-WrT06zTUzVRioNPRLPa0J6c8_eb5QFb4EG5wPpn-XlJSedjAw31MUNvFxKYQku_UwJF0CvvXLCozVnNM_dDNWsgBevzB8VBySbfW7XgYMRPJRlJe3Pjeues9tyGJvAxGJVjfo4nZyWusMF2G4f9w06m3Bxjc7ladgJR6F6pyI4Z65DCIL7G6G2y__agmNcKtFwCS_Q==

integration_tests/example_filesystems/v0.9/hwE1RKIXtF8hmQMvEXSTtg==

@@ -0,0 +1 @@
+XRx7Nqxt_zuPNo7h8_j1LLVzqzIZg9qAYGRN9Iuq3XBc11Y7_RoQsg==

integration_tests/example_filesystems_test.go

@@ -11,8 +11,7 @@ import (
 
 const statusTxtContent = "It works!\n"
 
-// checkStatusTxt - read file "filename" and verify that it contains
-// "It works!\n"
+// checkExampleFS - verify that "dir" contains the expected test files
 func checkExampleFS(t *testing.T, dir string) {
 	// Read regular file
 	statusFile := filepath.Join(dir, "status.txt")
@@ -47,6 +46,27 @@ func checkExampleFS(t *testing.T, dir string) {
 	testMkdirRmdir(t, dir)
 }
 
+// checkExampleFSLongnames - verify that "dir" contains the expected test files
+// plus the long file name test file
+func checkExampleFSLongnames(t *testing.T, dir string) {
+	// regular tests
+	checkExampleFS(t, dir)
+	// long name test file
+	longname := "longname_255_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" +
+		"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" +
+		"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" +
+		"xxxxxxxxxxxxxxxxxxxxxxxx"
+	contentBytes, err := ioutil.ReadFile(filepath.Join(dir, longname))
+	if err != nil {
+		t.Fatal(err)
+	}
+	content := string(contentBytes)
+	if content != statusTxtContent {
+		t.Errorf("longname_255: unexpected content: %s\n", content)
+	}
+
+}
+
 // Test example_filesystems/v0.4
 // with password mount and -masterkey mount
 func TestExampleFSv04(t *testing.T) {
@@ -159,3 +179,25 @@ func TestExampleFSv07(t *testing.T) {
 		t.Error(err)
 	}
 }
+
+// Test example_filesystems/v0.9
+// (gocryptfs v0.9 introduced long file name support)
+func TestExampleFSv09(t *testing.T) {
+	cDir := "example_filesystems/v0.9"
+	pDir := tmpDir + "TestExampleFsV09/"
+	err := os.Mkdir(pDir, 0777)
+	if err != nil {
+		t.Fatal(err)
+	}
+	mount(cDir, pDir, "-extpass", "echo test")
+	checkExampleFSLongnames(t, pDir)
+	unmount(pDir)
+	mount(cDir, pDir, "-masterkey", "1cafe3f4-bc316466-2214c47c-ecd89bf3-"+
+		"4e078fe4-f5faeea7-8b7cab02-884f5e1c")
+	checkExampleFSLongnames(t, pDir)
+	unmount(pDir)
+	err = os.Remove(pDir)
+	if err != nil {
+		t.Error(err)
+	}
+}