Add a new incremental parsing API

Change-Id: I6b921766836d58df0281fb23b2add3f62a478e14

webm_parser/tests/buffer_reader_test.cc

@@ -0,0 +1,164 @@
+// Copyright (c) 2016 The WebM 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 "webm/buffer_reader.h"
+
+#include <array>
+#include <cstdint>
+
+#include "gtest/gtest.h"
+
+using webm::BufferReader;
+using webm::Status;
+
+namespace {
+
+class BufferReaderTest : public testing::Test {};
+
+TEST_F(BufferReaderTest, Assignment) {
+  // Test the reader to make sure it resets correctly when assigned.
+  std::array<std::uint8_t, 4> buffer;
+  std::uint64_t count;
+  Status status;
+
+  BufferReader reader({});
+  EXPECT_EQ(0, reader.size());
+
+  status = reader.Read(buffer.size(), buffer.data(), &count);
+  EXPECT_EQ(Status::kEndOfFile, status.code);
+  EXPECT_EQ(0, count);
+
+  reader = {1, 2, 3, 4};
+  EXPECT_EQ(4, reader.size());
+
+  status = reader.Read(2, buffer.data(), &count);
+  EXPECT_EQ(Status::kOkCompleted, status.code);
+  EXPECT_EQ(2, count);
+
+  reader = {5, 6, 7, 8};
+  status = reader.Read(2, buffer.data() + 2, &count);
+  EXPECT_EQ(Status::kOkCompleted, status.code);
+  EXPECT_EQ(2, count);
+
+  std::array<std::uint8_t, 4> expected = {{1, 2, 5, 6}};
+  EXPECT_EQ(expected, buffer);
+}
+
+TEST_F(BufferReaderTest, Empty) {
+  // Test the reader to make sure it reports EOF on empty inputs.
+  std::array<std::uint8_t, 1> buffer;
+  std::uint64_t count;
+  Status status;
+
+  BufferReader reader({});
+
+  status = reader.Read(buffer.size(), buffer.data(), &count);
+  EXPECT_EQ(Status::kEndOfFile, status.code);
+  EXPECT_EQ(0, count);
+
+  status = reader.Skip(1, &count);
+  EXPECT_EQ(Status::kEndOfFile, status.code);
+  EXPECT_EQ(0, count);
+}
+
+TEST_F(BufferReaderTest, Read) {
+  // Test the Read method to make sure it reads data correctly.
+  std::array<std::uint8_t, 15> buffer{};
+  std::uint64_t count;
+  Status status;
+
+  BufferReader reader({0, 1, 2, 3, 4, 5, 6, 7, 8, 9});
+
+  status = reader.Read(5, buffer.data(), &count);
+  EXPECT_EQ(Status::kOkCompleted, status.code);
+  EXPECT_EQ(5, count);
+
+  status = reader.Read(10, buffer.data() + 5, &count);
+  EXPECT_EQ(Status::kOkPartial, status.code);
+  EXPECT_EQ(5, count);
+
+  std::array<std::uint8_t, 15> expected = {{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}};
+  EXPECT_EQ(expected, buffer);
+
+  status = reader.Read(buffer.size(), buffer.data(), &count);
+  EXPECT_EQ(Status::kEndOfFile, status.code);
+  EXPECT_EQ(0, count);
+}
+
+TEST_F(BufferReaderTest, Skip) {
+  // Test the Skip method to make sure it skips data correctly.
+  std::uint64_t count;
+  Status status;
+
+  BufferReader reader({0, 1, 2, 3, 4, 5, 6, 7, 8, 9});
+
+  status = reader.Skip(3, &count);
+  EXPECT_EQ(Status::kOkCompleted, status.code);
+  EXPECT_EQ(3, count);
+
+  status = reader.Skip(10, &count);
+  EXPECT_EQ(Status::kOkPartial, status.code);
+  EXPECT_EQ(7, count);
+
+  status = reader.Skip(1, &count);
+  EXPECT_EQ(Status::kEndOfFile, status.code);
+  EXPECT_EQ(0, count);
+}
+
+TEST_F(BufferReaderTest, ReadAndSkip) {
+  // Test the Read and Skip methods together to make sure they interact
+  // correclty.
+  std::array<std::uint8_t, 10> buffer = {};
+  std::uint64_t count;
+  Status status;
+
+  BufferReader reader({9, 8, 7, 6, 5, 4, 3, 2, 1, 0});
+
+  status = reader.Read(5, buffer.data(), &count);
+  EXPECT_EQ(Status::kOkCompleted, status.code);
+  EXPECT_EQ(5, count);
+
+  status = reader.Skip(3, &count);
+  EXPECT_EQ(Status::kOkCompleted, status.code);
+  EXPECT_EQ(3, count);
+
+  status = reader.Read(5, buffer.data() + 5, &count);
+  EXPECT_EQ(Status::kOkPartial, status.code);
+  EXPECT_EQ(2, count);
+
+  std::array<std::uint8_t, 10> expected = {{9, 8, 7, 6, 5, 1, 0, 0, 0, 0}};
+  EXPECT_EQ(expected, buffer);
+}
+
+TEST_F(BufferReaderTest, Position) {
+  std::array<std::uint8_t, 10> buffer = {};
+  std::uint64_t count;
+  Status status;
+
+  BufferReader reader({9, 8, 7, 6, 5, 4, 3, 2, 1, 0});
+  EXPECT_EQ(0, reader.Position());
+
+  status = reader.Read(5, buffer.data(), &count);
+  EXPECT_EQ(Status::kOkCompleted, status.code);
+  EXPECT_EQ(5, count);
+  EXPECT_EQ(5, reader.Position());
+
+  status = reader.Skip(3, &count);
+  EXPECT_EQ(Status::kOkCompleted, status.code);
+  EXPECT_EQ(3, count);
+  EXPECT_EQ(8, reader.Position());
+
+  status = reader.Read(5, buffer.data() + 5, &count);
+  EXPECT_EQ(Status::kOkPartial, status.code);
+  EXPECT_EQ(2, count);
+  EXPECT_EQ(10, reader.Position());
+
+  std::array<std::uint8_t, 10> expected = {{9, 8, 7, 6, 5, 1, 0, 0, 0, 0}};
+  EXPECT_EQ(expected, buffer);
+}
+
+}  // namespace