media/base/bit_reader_unittest.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/base/bit_reader.h"
   6
   7 #include "testing/gtest/include/gtest/gtest.h"
   8
   9 namespace media {
  10
  11 TEST(BitReaderTest, NormalOperationTest) {
  12   uint8 value8;
  13   uint64 value64;
  14   // 0101 0101 1001 1001 repeats 4 times
  15   uint8 buffer[] = {0x55, 0x99, 0x55, 0x99, 0x55, 0x99, 0x55, 0x99};
  16   BitReader reader1(buffer, 6);  // Initialize with 6 bytes only
  17
  18   EXPECT_TRUE(reader1.ReadBits(1, &value8));
  19   EXPECT_EQ(value8, 0);
  20   EXPECT_TRUE(reader1.ReadBits(8, &value8));
  21   EXPECT_EQ(value8, 0xab);  // 1010 1011
  22   EXPECT_TRUE(reader1.ReadBits(7, &value64));
  23   EXPECT_TRUE(reader1.ReadBits(32, &value64));
  24   EXPECT_EQ(value64, 0x55995599u);
  25   EXPECT_FALSE(reader1.ReadBits(1, &value8));
  26   value8 = 0xff;
  27   EXPECT_TRUE(reader1.ReadBits(0, &value8));
  28   EXPECT_EQ(value8, 0);
  29
  30   BitReader reader2(buffer, 8);
  31   EXPECT_TRUE(reader2.ReadBits(64, &value64));
  32   EXPECT_EQ(value64, 0x5599559955995599ull);
  33   EXPECT_FALSE(reader2.ReadBits(1, &value8));
  34   EXPECT_TRUE(reader2.ReadBits(0, &value8));
  35 }
  36
  37 TEST(BitReaderTest, ReadBeyondEndTest) {
  38   uint8 value8;
  39   uint8 buffer[] = {0x12};
  40   BitReader reader1(buffer, sizeof(buffer));
  41
  42   EXPECT_TRUE(reader1.ReadBits(4, &value8));
  43   EXPECT_FALSE(reader1.ReadBits(5, &value8));
  44   EXPECT_FALSE(reader1.ReadBits(1, &value8));
  45   EXPECT_TRUE(reader1.ReadBits(0, &value8));
  46 }
  47
  48 TEST(BitReaderTest, SkipBitsTest) {
  49   uint8 value8;
  50   uint8 buffer[] = { 0x0a, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 };
  51   BitReader reader1(buffer, sizeof(buffer));
  52
  53   EXPECT_TRUE(reader1.SkipBits(2));
  54   EXPECT_TRUE(reader1.ReadBits(3, &value8));
  55   EXPECT_EQ(value8, 1);
  56   EXPECT_TRUE(reader1.SkipBits(11));
  57   EXPECT_TRUE(reader1.ReadBits(8, &value8));
  58   EXPECT_EQ(value8, 3);
  59   EXPECT_TRUE(reader1.SkipBits(76));
  60   EXPECT_TRUE(reader1.ReadBits(4, &value8));
  61   EXPECT_EQ(value8, 13);
  62   EXPECT_FALSE(reader1.SkipBits(100));
  63   EXPECT_TRUE(reader1.SkipBits(0));
  64   EXPECT_FALSE(reader1.SkipBits(1));
  65 }
  66
  67 TEST(BitReaderTest, BitsReadTest) {
  68   int value;
  69   bool flag;
  70   uint8 buffer[] = { 0x0a, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 };
  71   BitReader reader1(buffer, sizeof(buffer));
  72   EXPECT_EQ(reader1.bits_available(), 120);
  73
  74   EXPECT_TRUE(reader1.SkipBits(2));
  75   EXPECT_EQ(reader1.bits_read(), 2);
  76   EXPECT_EQ(reader1.bits_available(), 118);
  77   EXPECT_TRUE(reader1.ReadBits(3, &value));
  78   EXPECT_EQ(reader1.bits_read(), 5);
  79   EXPECT_EQ(reader1.bits_available(), 115);
  80   EXPECT_TRUE(reader1.ReadFlag(&flag));
  81   EXPECT_EQ(reader1.bits_read(), 6);
  82   EXPECT_EQ(reader1.bits_available(), 114);
  83   EXPECT_TRUE(reader1.SkipBits(76));
  84   EXPECT_EQ(reader1.bits_read(), 82);
  85   EXPECT_EQ(reader1.bits_available(), 38);
  86 }
  87
  88 }  // namespace media