Function TestFDTable

pkg/sentry/kernel/fd_table_test.go:143–193

TestFDTable does a set of simple tests to make sure simple adds, removes, GetRefs, and DecRefs work. The ordering is just weird enough that a table-driven approach seemed clumsy.

(t *testing.T)

// GetRefs, and DecRefs work. The ordering is just weird enough that a
// table-driven approach seemed clumsy.
func TestFDTable(t *testing.T) {
	runTest(t, func(ctx context.Context, fdTable *FDTable, fd *vfs.FileDescription, limitSet *limits.LimitSet) {
		// Cap the limit at one.
		limitSet.Set(limits.NumberOfFiles, limits.Limit{1, maxFD}, true)

		if _, err := fdTable.NewFDs(ctx, 0, []*vfs.FileDescription{fd}, FDFlags{}); err != nil {
			t.Fatalf("Adding an FD to an empty 1-size map: got %v, want nil", err)
		}

		if _, err := fdTable.NewFDs(ctx, 0, []*vfs.FileDescription{fd}, FDFlags{}); err == nil {
			t.Fatalf("Adding an FD to a filled 1-size map: got nil, wanted an error")
		}

		// Remove the previous limit.
		limitSet.Set(limits.NumberOfFiles, limits.Limit{maxFD, maxFD}, true)

		if fds, err := fdTable.NewFDs(ctx, 0, []*vfs.FileDescription{fd}, FDFlags{}); err != nil {
			t.Fatalf("Adding an FD to a resized map: got %v, want nil", err)
		} else if len(fds) != 1 || fds[0] != 1 {
			t.Fatalf("Added an FD to a resized map: got %v, want {1}", fds)
		}

		if df, err := fdTable.NewFDAt(ctx, 1, fd, FDFlags{}); err != nil {
			t.Fatalf("Replacing FD 1 via fdTable.NewFDAt(1, r, FDFlags{}): got %v, wanted nil", err)
		} else if df != nil {
			t.Fatalf("fdTable.NewFDAt(1, r, FDFlags{}) displaced FD")
		}

		if _, err := fdTable.NewFDAt(ctx, maxFD+1, fd, FDFlags{}); err == nil {
			t.Fatalf("Using an FD that was too large via fdTable.NewFDAt(%v, r, FDFlags{}): got nil, wanted an error", maxFD+1)
		}

		if ref, _ := fdTable.Get(1); ref == nil {
			t.Fatalf("fdTable.Get(1): got nil, wanted %v", fd)
		}

		if ref, _ := fdTable.Get(2); ref != nil {
			t.Fatalf("fdTable.Get(2): got a %v, wanted nil", ref)
		}

		ref := fdTable.Remove(ctx, 1)
		if ref == nil {
			t.Fatalf("fdTable.Remove(1) for an existing FD: failed, want success")
		}
		ref.DecRef(ctx)

		if ref := fdTable.Remove(ctx, 1); ref != nil {
			t.Fatalf("r.Remove(1) for a removed FD: got success, want failure")
		}
	})
}

func TestDescriptorFlags(t *testing.T) {
	runTest(t, func(ctx context.Context, fdTable *FDTable, fd *vfs.FileDescription, _ *limits.LimitSet) {