Check in gVisor.

PiperOrigin-RevId: 194583126
Change-Id: Ica1d8821a90f74e7e745962d71801c598c652463

1 files changed, 136 insertions, 0 deletions

diff --git a/pkg/sentry/fs/lock/lock_range_test.go b/pkg/sentry/fs/lock/lock_range_test.go
new file mode 100644
index 000000000..06a37c701
--- /dev/null
+++ b/pkg/sentry/fs/lock/lock_range_test.go
@@ -0,0 +1,136 @@
+// Copyright 2018 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package lock
+
+import (
+	"syscall"
+	"testing"
+)
+
+func TestComputeRange(t *testing.T) {
+	tests := []struct {
+		// Description of test.
+		name string
+
+		// Requested start of the lock range.
+		start int64
+
+		// Requested length of the lock range,
+		// can be negative :(
+		length int64
+
+		// Pre-computed file offset based on whence.
+		// Will be added to start.
+		offset int64
+
+		// Expected error.
+		err error
+
+		// If error is nil, the expected LockRange.
+		LockRange
+	}{
+		{
+			name:      "offset, start, and length all zero",
+			LockRange: LockRange{Start: 0, End: LockEOF},
+		},
+		{
+			name:      "zero offset, zero start, positive length",
+			start:     0,
+			length:    4096,
+			offset:    0,
+			LockRange: LockRange{Start: 0, End: 4096},
+		},
+		{
+			name:   "zero offset, negative start",
+			start:  -4096,
+			offset: 0,
+			err:    syscall.EINVAL,
+		},
+		{
+			name:      "large offset, negative start, positive length",
+			start:     -2048,
+			length:    2048,
+			offset:    4096,
+			LockRange: LockRange{Start: 2048, End: 4096},
+		},
+		{
+			name:      "large offset, negative start, zero length",
+			start:     -2048,
+			length:    0,
+			offset:    4096,
+			LockRange: LockRange{Start: 2048, End: LockEOF},
+		},
+		{
+			name:   "zero offset, zero start, negative length",
+			start:  0,
+			length: -4096,
+			offset: 0,
+			err:    syscall.EINVAL,
+		},
+		{
+			name:      "large offset, zero start, negative length",
+			start:     0,
+			length:    -4096,
+			offset:    4096,
+			LockRange: LockRange{Start: 0, End: 4096},
+		},
+		{
+			name:      "offset, start, and length equal, length is negative",
+			start:     1024,
+			length:    -1024,
+			offset:    1024,
+			LockRange: LockRange{Start: 1024, End: 2048},
+		},
+		{
+			name:      "offset, start, and length equal, start is negative",
+			start:     -1024,
+			length:    1024,
+			offset:    1024,
+			LockRange: LockRange{Start: 0, End: 1024},
+		},
+		{
+			name:      "offset, start, and length equal, offset is negative",
+			start:     1024,
+			length:    1024,
+			offset:    -1024,
+			LockRange: LockRange{Start: 0, End: 1024},
+		},
+		{
+			name:   "offset, start, and length equal, all negative",
+			start:  -1024,
+			length: -1024,
+			offset: -1024,
+			err:    syscall.EINVAL,
+		},
+		{
+			name:      "offset, start, and length equal, all positive",
+			start:     1024,
+			length:    1024,
+			offset:    1024,
+			LockRange: LockRange{Start: 2048, End: 3072},
+		},
+	}
+
+	for _, test := range tests {
+		rng, err := ComputeRange(test.start, test.length, test.offset)
+		if err != test.err {
+			t.Errorf("%s: lockRange(%d, %d, %d) got error %v, want %v", test.name, test.start, test.length, test.offset, err, test.err)
+			continue
+		}
+		if err == nil && rng != test.LockRange {
+			t.Errorf("%s: lockRange(%d, %d, %d) got LockRange %v, want %v", test.name, test.start, test.length, test.offset, rng, test.LockRange)
+		}
+	}
+}