1 files changed, 202 insertions, 0 deletions
diff --git a/third_party/libwebrtc/net/dcsctp/common/sequence_numbers_test.cc b/third_party/libwebrtc/net/dcsctp/common/sequence_numbers_test.cc
new file mode 100644
index 0000000000..c4842f089e
--- /dev/null
+++ b/third_party/libwebrtc/net/dcsctp/common/sequence_numbers_test.cc
@@ -0,0 +1,202 @@
+/*
+ *  Copyright (c) 2021 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+#include "net/dcsctp/common/sequence_numbers.h"
+
+#include "test/gmock.h"
+
+namespace dcsctp {
+namespace {
+
+using Wrapped = webrtc::StrongAlias<class WrappedTag, uint16_t>;
+using TestSequence = UnwrappedSequenceNumber<Wrapped>;
+
+TEST(SequenceNumbersTest, SimpleUnwrapping) {
+  TestSequence::Unwrapper unwrapper;
+
+  TestSequence s0 = unwrapper.Unwrap(Wrapped(0));
+  TestSequence s1 = unwrapper.Unwrap(Wrapped(1));
+  TestSequence s2 = unwrapper.Unwrap(Wrapped(2));
+  TestSequence s3 = unwrapper.Unwrap(Wrapped(3));
+
+  EXPECT_LT(s0, s1);
+  EXPECT_LT(s0, s2);
+  EXPECT_LT(s0, s3);
+  EXPECT_LT(s1, s2);
+  EXPECT_LT(s1, s3);
+  EXPECT_LT(s2, s3);
+
+  EXPECT_EQ(TestSequence::Difference(s1, s0), 1);
+  EXPECT_EQ(TestSequence::Difference(s2, s0), 2);
+  EXPECT_EQ(TestSequence::Difference(s3, s0), 3);
+
+  EXPECT_GT(s1, s0);
+  EXPECT_GT(s2, s0);
+  EXPECT_GT(s3, s0);
+  EXPECT_GT(s2, s1);
+  EXPECT_GT(s3, s1);
+  EXPECT_GT(s3, s2);
+
+  s0.Increment();
+  EXPECT_EQ(s0, s1);
+  s1.Increment();
+  EXPECT_EQ(s1, s2);
+  s2.Increment();
+  EXPECT_EQ(s2, s3);
+
+  EXPECT_EQ(TestSequence::AddTo(s0, 2), s3);
+}
+
+TEST(SequenceNumbersTest, MidValueUnwrapping) {
+  TestSequence::Unwrapper unwrapper;
+
+  TestSequence s0 = unwrapper.Unwrap(Wrapped(0x7FFE));
+  TestSequence s1 = unwrapper.Unwrap(Wrapped(0x7FFF));
+  TestSequence s2 = unwrapper.Unwrap(Wrapped(0x8000));
+  TestSequence s3 = unwrapper.Unwrap(Wrapped(0x8001));
+
+  EXPECT_LT(s0, s1);
+  EXPECT_LT(s0, s2);
+  EXPECT_LT(s0, s3);
+  EXPECT_LT(s1, s2);
+  EXPECT_LT(s1, s3);
+  EXPECT_LT(s2, s3);
+
+  EXPECT_EQ(TestSequence::Difference(s1, s0), 1);
+  EXPECT_EQ(TestSequence::Difference(s2, s0), 2);
+  EXPECT_EQ(TestSequence::Difference(s3, s0), 3);
+
+  EXPECT_GT(s1, s0);
+  EXPECT_GT(s2, s0);
+  EXPECT_GT(s3, s0);
+  EXPECT_GT(s2, s1);
+  EXPECT_GT(s3, s1);
+  EXPECT_GT(s3, s2);
+
+  s0.Increment();
+  EXPECT_EQ(s0, s1);
+  s1.Increment();
+  EXPECT_EQ(s1, s2);
+  s2.Increment();
+  EXPECT_EQ(s2, s3);
+
+  EXPECT_EQ(TestSequence::AddTo(s0, 2), s3);
+}
+
+TEST(SequenceNumbersTest, WrappedUnwrapping) {
+  TestSequence::Unwrapper unwrapper;
+
+  TestSequence s0 = unwrapper.Unwrap(Wrapped(0xFFFE));
+  TestSequence s1 = unwrapper.Unwrap(Wrapped(0xFFFF));
+  TestSequence s2 = unwrapper.Unwrap(Wrapped(0x0000));
+  TestSequence s3 = unwrapper.Unwrap(Wrapped(0x0001));
+
+  EXPECT_LT(s0, s1);
+  EXPECT_LT(s0, s2);
+  EXPECT_LT(s0, s3);
+  EXPECT_LT(s1, s2);
+  EXPECT_LT(s1, s3);
+  EXPECT_LT(s2, s3);
+
+  EXPECT_EQ(TestSequence::Difference(s1, s0), 1);
+  EXPECT_EQ(TestSequence::Difference(s2, s0), 2);
+  EXPECT_EQ(TestSequence::Difference(s3, s0), 3);
+
+  EXPECT_GT(s1, s0);
+  EXPECT_GT(s2, s0);
+  EXPECT_GT(s3, s0);
+  EXPECT_GT(s2, s1);
+  EXPECT_GT(s3, s1);
+  EXPECT_GT(s3, s2);
+
+  s0.Increment();
+  EXPECT_EQ(s0, s1);
+  s1.Increment();
+  EXPECT_EQ(s1, s2);
+  s2.Increment();
+  EXPECT_EQ(s2, s3);
+
+  EXPECT_EQ(TestSequence::AddTo(s0, 2), s3);
+}
+
+TEST(SequenceNumbersTest, WrapAroundAFewTimes) {
+  TestSequence::Unwrapper unwrapper;
+
+  TestSequence s0 = unwrapper.Unwrap(Wrapped(0));
+  TestSequence prev = s0;
+
+  for (uint32_t i = 1; i < 65536 * 3; i++) {
+    uint16_t wrapped = static_cast<uint16_t>(i);
+    TestSequence si = unwrapper.Unwrap(Wrapped(wrapped));
+
+    EXPECT_LT(s0, si);
+    EXPECT_LT(prev, si);
+    prev = si;
+  }
+}
+
+TEST(SequenceNumbersTest, IncrementIsSameAsWrapped) {
+  TestSequence::Unwrapper unwrapper;
+
+  TestSequence s0 = unwrapper.Unwrap(Wrapped(0));
+
+  for (uint32_t i = 1; i < 65536 * 2; i++) {
+    uint16_t wrapped = static_cast<uint16_t>(i);
+    TestSequence si = unwrapper.Unwrap(Wrapped(wrapped));
+
+    s0.Increment();
+    EXPECT_EQ(s0, si);
+  }
+}
+
+TEST(SequenceNumbersTest, UnwrappingLargerNumberIsAlwaysLarger) {
+  TestSequence::Unwrapper unwrapper;
+
+  for (uint32_t i = 1; i < 65536 * 2; i++) {
+    uint16_t wrapped = static_cast<uint16_t>(i);
+    TestSequence si = unwrapper.Unwrap(Wrapped(wrapped));
+
+    EXPECT_GT(unwrapper.Unwrap(Wrapped(wrapped + 1)), si);
+    EXPECT_GT(unwrapper.Unwrap(Wrapped(wrapped + 5)), si);
+    EXPECT_GT(unwrapper.Unwrap(Wrapped(wrapped + 10)), si);
+    EXPECT_GT(unwrapper.Unwrap(Wrapped(wrapped + 100)), si);
+  }
+}
+
+TEST(SequenceNumbersTest, UnwrappingSmallerNumberIsAlwaysSmaller) {
+  TestSequence::Unwrapper unwrapper;
+
+  for (uint32_t i = 1; i < 65536 * 2; i++) {
+    uint16_t wrapped = static_cast<uint16_t>(i);
+    TestSequence si = unwrapper.Unwrap(Wrapped(wrapped));
+
+    EXPECT_LT(unwrapper.Unwrap(Wrapped(wrapped - 1)), si);
+    EXPECT_LT(unwrapper.Unwrap(Wrapped(wrapped - 5)), si);
+    EXPECT_LT(unwrapper.Unwrap(Wrapped(wrapped - 10)), si);
+    EXPECT_LT(unwrapper.Unwrap(Wrapped(wrapped - 100)), si);
+  }
+}
+
+TEST(SequenceNumbersTest, DifferenceIsAbsolute) {
+  TestSequence::Unwrapper unwrapper;
+
+  TestSequence this_value = unwrapper.Unwrap(Wrapped(10));
+  TestSequence other_value = TestSequence::AddTo(this_value, 100);
+
+  EXPECT_EQ(TestSequence::Difference(this_value, other_value), 100);
+  EXPECT_EQ(TestSequence::Difference(other_value, this_value), 100);
+
+  TestSequence minus_value = TestSequence::AddTo(this_value, -100);
+
+  EXPECT_EQ(TestSequence::Difference(this_value, minus_value), 100);
+  EXPECT_EQ(TestSequence::Difference(minus_value, this_value), 100);
+}
+
+}  // namespace
+}  // namespace dcsctp