| /* |
| * Copyright 2015 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 "webrtc/base/arraysize.h" |
| #include "webrtc/base/bitbuffer.h" |
| #include "webrtc/base/bytebuffer.h" |
| #include "webrtc/base/common.h" |
| #include "webrtc/base/gunit.h" |
| |
| namespace rtc { |
| |
| TEST(BitBufferTest, ConsumeBits) { |
| const uint8_t bytes[64] = {0}; |
| BitBuffer buffer(bytes, 32); |
| uint64_t total_bits = 32 * 8; |
| EXPECT_EQ(total_bits, buffer.RemainingBitCount()); |
| EXPECT_TRUE(buffer.ConsumeBits(3)); |
| total_bits -= 3; |
| EXPECT_EQ(total_bits, buffer.RemainingBitCount()); |
| EXPECT_TRUE(buffer.ConsumeBits(3)); |
| total_bits -= 3; |
| EXPECT_EQ(total_bits, buffer.RemainingBitCount()); |
| EXPECT_TRUE(buffer.ConsumeBits(15)); |
| total_bits -= 15; |
| EXPECT_EQ(total_bits, buffer.RemainingBitCount()); |
| EXPECT_TRUE(buffer.ConsumeBits(37)); |
| total_bits -= 37; |
| EXPECT_EQ(total_bits, buffer.RemainingBitCount()); |
| |
| EXPECT_FALSE(buffer.ConsumeBits(32 * 8)); |
| EXPECT_EQ(total_bits, buffer.RemainingBitCount()); |
| } |
| |
| TEST(BitBufferTest, ReadBytesAligned) { |
| const uint8_t bytes[] = {0x0A, 0xBC, 0xDE, 0xF1, 0x23, 0x45, 0x67, 0x89}; |
| uint8_t val8; |
| uint16_t val16; |
| uint32_t val32; |
| BitBuffer buffer(bytes, 8); |
| EXPECT_TRUE(buffer.ReadUInt8(&val8)); |
| EXPECT_EQ(0x0Au, val8); |
| EXPECT_TRUE(buffer.ReadUInt8(&val8)); |
| EXPECT_EQ(0xBCu, val8); |
| EXPECT_TRUE(buffer.ReadUInt16(&val16)); |
| EXPECT_EQ(0xDEF1u, val16); |
| EXPECT_TRUE(buffer.ReadUInt32(&val32)); |
| EXPECT_EQ(0x23456789u, val32); |
| } |
| |
| TEST(BitBufferTest, ReadBytesOffset4) { |
| const uint8_t bytes[] = {0x0A, 0xBC, 0xDE, 0xF1, 0x23, |
| 0x45, 0x67, 0x89, 0x0A}; |
| uint8_t val8; |
| uint16_t val16; |
| uint32_t val32; |
| BitBuffer buffer(bytes, 9); |
| EXPECT_TRUE(buffer.ConsumeBits(4)); |
| |
| EXPECT_TRUE(buffer.ReadUInt8(&val8)); |
| EXPECT_EQ(0xABu, val8); |
| EXPECT_TRUE(buffer.ReadUInt8(&val8)); |
| EXPECT_EQ(0xCDu, val8); |
| EXPECT_TRUE(buffer.ReadUInt16(&val16)); |
| EXPECT_EQ(0xEF12u, val16); |
| EXPECT_TRUE(buffer.ReadUInt32(&val32)); |
| EXPECT_EQ(0x34567890u, val32); |
| } |
| |
| TEST(BitBufferTest, ReadBytesOffset3) { |
| // The pattern we'll check against is counting down from 0b1111. It looks |
| // weird here because it's all offset by 3. |
| // Byte pattern is: |
| // 56701234 |
| // 0b00011111, |
| // 0b11011011, |
| // 0b10010111, |
| // 0b01010011, |
| // 0b00001110, |
| // 0b11001010, |
| // 0b10000110, |
| // 0b01000010 |
| // xxxxx <-- last 5 bits unused. |
| |
| // The bytes. It almost looks like counting down by two at a time, except the |
| // jump at 5->3->0, since that's when the high bit is turned off. |
| const uint8_t bytes[] = {0x1F, 0xDB, 0x97, 0x53, 0x0E, 0xCA, 0x86, 0x42}; |
| |
| uint8_t val8; |
| uint16_t val16; |
| uint32_t val32; |
| BitBuffer buffer(bytes, 8); |
| EXPECT_TRUE(buffer.ConsumeBits(3)); |
| EXPECT_TRUE(buffer.ReadUInt8(&val8)); |
| EXPECT_EQ(0xFEu, val8); |
| EXPECT_TRUE(buffer.ReadUInt16(&val16)); |
| EXPECT_EQ(0xDCBAu, val16); |
| EXPECT_TRUE(buffer.ReadUInt32(&val32)); |
| EXPECT_EQ(0x98765432u, val32); |
| // 5 bits left unread. Not enough to read a uint8_t. |
| EXPECT_EQ(5u, buffer.RemainingBitCount()); |
| EXPECT_FALSE(buffer.ReadUInt8(&val8)); |
| } |
| |
| TEST(BitBufferTest, ReadBits) { |
| // Bit values are: |
| // 0b01001101, |
| // 0b00110010 |
| const uint8_t bytes[] = {0x4D, 0x32}; |
| uint32_t val; |
| BitBuffer buffer(bytes, 2); |
| EXPECT_TRUE(buffer.ReadBits(&val, 3)); |
| // 0b010 |
| EXPECT_EQ(0x2u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 2)); |
| // 0b01 |
| EXPECT_EQ(0x1u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 7)); |
| // 0b1010011 |
| EXPECT_EQ(0x53u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 2)); |
| // 0b00 |
| EXPECT_EQ(0x0u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 1)); |
| // 0b1 |
| EXPECT_EQ(0x1u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 1)); |
| // 0b0 |
| EXPECT_EQ(0x0u, val); |
| |
| EXPECT_FALSE(buffer.ReadBits(&val, 1)); |
| } |
| |
| TEST(BitBufferTest, SetOffsetValues) { |
| uint8_t bytes[4] = {0}; |
| BitBufferWriter buffer(bytes, 4); |
| |
| size_t byte_offset, bit_offset; |
| // Bit offsets are [0,7]. |
| EXPECT_TRUE(buffer.Seek(0, 0)); |
| EXPECT_TRUE(buffer.Seek(0, 7)); |
| buffer.GetCurrentOffset(&byte_offset, &bit_offset); |
| EXPECT_EQ(0u, byte_offset); |
| EXPECT_EQ(7u, bit_offset); |
| EXPECT_FALSE(buffer.Seek(0, 8)); |
| buffer.GetCurrentOffset(&byte_offset, &bit_offset); |
| EXPECT_EQ(0u, byte_offset); |
| EXPECT_EQ(7u, bit_offset); |
| // Byte offsets are [0,length]. At byte offset length, the bit offset must be |
| // 0. |
| EXPECT_TRUE(buffer.Seek(0, 0)); |
| EXPECT_TRUE(buffer.Seek(2, 4)); |
| buffer.GetCurrentOffset(&byte_offset, &bit_offset); |
| EXPECT_EQ(2u, byte_offset); |
| EXPECT_EQ(4u, bit_offset); |
| EXPECT_TRUE(buffer.Seek(4, 0)); |
| EXPECT_FALSE(buffer.Seek(5, 0)); |
| buffer.GetCurrentOffset(&byte_offset, &bit_offset); |
| EXPECT_EQ(4u, byte_offset); |
| EXPECT_EQ(0u, bit_offset); |
| EXPECT_FALSE(buffer.Seek(4, 1)); |
| |
| // Disable death test on Android because it relies on fork() and doesn't play |
| // nicely. |
| #if defined(GTEST_HAS_DEATH_TEST) |
| #if !defined(WEBRTC_ANDROID) |
| // Passing a NULL out parameter is death. |
| EXPECT_DEATH(buffer.GetCurrentOffset(&byte_offset, NULL), ""); |
| #endif |
| #endif |
| } |
| |
| uint64_t GolombEncoded(uint32_t val) { |
| val++; |
| uint32_t bit_counter = val; |
| uint64_t bit_count = 0; |
| while (bit_counter > 0) { |
| bit_count++; |
| bit_counter >>= 1; |
| } |
| return static_cast<uint64_t>(val) << (64 - (bit_count * 2 - 1)); |
| } |
| |
| TEST(BitBufferTest, GolombUint32Values) { |
| ByteBufferWriter byteBuffer; |
| byteBuffer.Resize(16); |
| BitBuffer buffer(reinterpret_cast<const uint8_t*>(byteBuffer.Data()), |
| byteBuffer.Capacity()); |
| // Test over the uint32_t range with a large enough step that the test doesn't |
| // take forever. Around 20,000 iterations should do. |
| const int kStep = std::numeric_limits<uint32_t>::max() / 20000; |
| for (uint32_t i = 0; i < std::numeric_limits<uint32_t>::max() - kStep; |
| i += kStep) { |
| uint64_t encoded_val = GolombEncoded(i); |
| byteBuffer.Clear(); |
| byteBuffer.WriteUInt64(encoded_val); |
| uint32_t decoded_val; |
| EXPECT_TRUE(buffer.Seek(0, 0)); |
| EXPECT_TRUE(buffer.ReadExponentialGolomb(&decoded_val)); |
| EXPECT_EQ(i, decoded_val); |
| } |
| } |
| |
| TEST(BitBufferTest, SignedGolombValues) { |
| uint8_t golomb_bits[] = { |
| 0x80, // 1 |
| 0x40, // 010 |
| 0x60, // 011 |
| 0x20, // 00100 |
| 0x38, // 00111 |
| }; |
| int32_t expected[] = {0, 1, -1, 2, -3}; |
| for (size_t i = 0; i < sizeof(golomb_bits); ++i) { |
| BitBuffer buffer(&golomb_bits[i], 1); |
| int32_t decoded_val; |
| ASSERT_TRUE(buffer.ReadSignedExponentialGolomb(&decoded_val)); |
| EXPECT_EQ(expected[i], decoded_val) |
| << "Mismatch in expected/decoded value for golomb_bits[" << i |
| << "]: " << static_cast<int>(golomb_bits[i]); |
| } |
| } |
| |
| TEST(BitBufferTest, NoGolombOverread) { |
| const uint8_t bytes[] = {0x00, 0xFF, 0xFF}; |
| // Make sure the bit buffer correctly enforces byte length on golomb reads. |
| // If it didn't, the above buffer would be valid at 3 bytes. |
| BitBuffer buffer(bytes, 1); |
| uint32_t decoded_val; |
| EXPECT_FALSE(buffer.ReadExponentialGolomb(&decoded_val)); |
| |
| BitBuffer longer_buffer(bytes, 2); |
| EXPECT_FALSE(longer_buffer.ReadExponentialGolomb(&decoded_val)); |
| |
| BitBuffer longest_buffer(bytes, 3); |
| EXPECT_TRUE(longest_buffer.ReadExponentialGolomb(&decoded_val)); |
| // Golomb should have read 9 bits, so 0x01FF, and since it is golomb, the |
| // result is 0x01FF - 1 = 0x01FE. |
| EXPECT_EQ(0x01FEu, decoded_val); |
| } |
| |
| TEST(BitBufferWriterTest, SymmetricReadWrite) { |
| uint8_t bytes[16] = {0}; |
| BitBufferWriter buffer(bytes, 4); |
| |
| // Write some bit data at various sizes. |
| EXPECT_TRUE(buffer.WriteBits(0x2u, 3)); |
| EXPECT_TRUE(buffer.WriteBits(0x1u, 2)); |
| EXPECT_TRUE(buffer.WriteBits(0x53u, 7)); |
| EXPECT_TRUE(buffer.WriteBits(0x0u, 2)); |
| EXPECT_TRUE(buffer.WriteBits(0x1u, 1)); |
| EXPECT_TRUE(buffer.WriteBits(0x1ABCDu, 17)); |
| // That should be all that fits in the buffer. |
| EXPECT_FALSE(buffer.WriteBits(1, 1)); |
| |
| EXPECT_TRUE(buffer.Seek(0, 0)); |
| uint32_t val; |
| EXPECT_TRUE(buffer.ReadBits(&val, 3)); |
| EXPECT_EQ(0x2u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 2)); |
| EXPECT_EQ(0x1u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 7)); |
| EXPECT_EQ(0x53u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 2)); |
| EXPECT_EQ(0x0u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 1)); |
| EXPECT_EQ(0x1u, val); |
| EXPECT_TRUE(buffer.ReadBits(&val, 17)); |
| EXPECT_EQ(0x1ABCDu, val); |
| // And there should be nothing left. |
| EXPECT_FALSE(buffer.ReadBits(&val, 1)); |
| } |
| |
| TEST(BitBufferWriterTest, SymmetricBytesMisaligned) { |
| uint8_t bytes[16] = {0}; |
| BitBufferWriter buffer(bytes, 16); |
| |
| // Offset 3, to get things misaligned. |
| EXPECT_TRUE(buffer.ConsumeBits(3)); |
| EXPECT_TRUE(buffer.WriteUInt8(0x12u)); |
| EXPECT_TRUE(buffer.WriteUInt16(0x3456u)); |
| EXPECT_TRUE(buffer.WriteUInt32(0x789ABCDEu)); |
| |
| buffer.Seek(0, 3); |
| uint8_t val8; |
| uint16_t val16; |
| uint32_t val32; |
| EXPECT_TRUE(buffer.ReadUInt8(&val8)); |
| EXPECT_EQ(0x12u, val8); |
| EXPECT_TRUE(buffer.ReadUInt16(&val16)); |
| EXPECT_EQ(0x3456u, val16); |
| EXPECT_TRUE(buffer.ReadUInt32(&val32)); |
| EXPECT_EQ(0x789ABCDEu, val32); |
| } |
| |
| TEST(BitBufferWriterTest, SymmetricGolomb) { |
| char test_string[] = "my precious"; |
| uint8_t bytes[64] = {0}; |
| BitBufferWriter buffer(bytes, 64); |
| for (size_t i = 0; i < arraysize(test_string); ++i) { |
| EXPECT_TRUE(buffer.WriteExponentialGolomb(test_string[i])); |
| } |
| buffer.Seek(0, 0); |
| for (size_t i = 0; i < arraysize(test_string); ++i) { |
| uint32_t val; |
| EXPECT_TRUE(buffer.ReadExponentialGolomb(&val)); |
| EXPECT_LE(val, std::numeric_limits<uint8_t>::max()); |
| EXPECT_EQ(test_string[i], static_cast<char>(val)); |
| } |
| } |
| |
| TEST(BitBufferWriterTest, WriteClearsBits) { |
| uint8_t bytes[] = {0xFF, 0xFF}; |
| BitBufferWriter buffer(bytes, 2); |
| EXPECT_TRUE(buffer.ConsumeBits(3)); |
| EXPECT_TRUE(buffer.WriteBits(0, 1)); |
| EXPECT_EQ(0xEFu, bytes[0]); |
| EXPECT_TRUE(buffer.WriteBits(0, 3)); |
| EXPECT_EQ(0xE1u, bytes[0]); |
| EXPECT_TRUE(buffer.WriteBits(0, 2)); |
| EXPECT_EQ(0xE0u, bytes[0]); |
| EXPECT_EQ(0x7F, bytes[1]); |
| } |
| |
| } // namespace rtc |