github.com/dctrud/umoci@v0.4.3-0.20191016193643-05a1d37de015/oci/casext/utils_dir_test.go (about)

     1  /*
     2   * umoci: Umoci Modifies Open Containers' Images
     3   * Copyright (C) 2016, 2017, 2018 SUSE LLC.
     4   *
     5   * Licensed under the Apache License, Version 2.0 (the "License");
     6   * you may not use this file except in compliance with the License.
     7   * You may obtain a copy of the License at
     8   *
     9   *    http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   */
    17  
    18  package casext
    19  
    20  import (
    21  	"os"
    22  	"syscall"
    23  	"testing"
    24  )
    25  
    26  // readonly makes the given path read-only (by bind-mounting it as "ro").
    27  // TODO: This should be done through an interface restriction in the test
    28  //       (which is then backed up by the readonly mount if necessary). The fact
    29  //       this test is necessary is a sign that we need a better split up of the
    30  //       CAS interface.
    31  // Copied from oci/cas/drivers/dir/dir_test.go.
    32  func readonly(t *testing.T, path string) {
    33  	if os.Geteuid() != 0 {
    34  		t.Log("readonly tests only work with root privileges")
    35  		t.Skip()
    36  	}
    37  
    38  	t.Logf("mounting %s as readonly", path)
    39  
    40  	if err := syscall.Mount(path, path, "", syscall.MS_BIND|syscall.MS_RDONLY, ""); err != nil {
    41  		t.Fatalf("mount %s as ro: %s", path, err)
    42  	}
    43  	if err := syscall.Mount("none", path, "", syscall.MS_BIND|syscall.MS_REMOUNT|syscall.MS_RDONLY, ""); err != nil {
    44  		t.Fatalf("mount %s as ro: %s", path, err)
    45  	}
    46  }
    47  
    48  // readwrite undoes the effect of readonly.
    49  // Copied from oci/cas/drivers/dir/dir_test.go.
    50  func readwrite(t *testing.T, path string) {
    51  	if os.Geteuid() != 0 {
    52  		t.Log("readonly tests only work with root privileges")
    53  		t.Skip()
    54  	}
    55  
    56  	if err := syscall.Unmount(path, syscall.MNT_DETACH); err != nil {
    57  		t.Fatalf("unmount %s: %s", path, err)
    58  	}
    59  }