Add 64-bit version of BitBuffer::ReadBits
Bug: webrtc:11933
Change-Id: Ie935192d2c81d7c24b83561711d59a7eff53db04
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/215966
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Björn Terelius <terelius@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33997}
diff --git a/rtc_base/bit_buffer_unittest.cc b/rtc_base/bit_buffer_unittest.cc
index 656682c..86c4f7f 100644
--- a/rtc_base/bit_buffer_unittest.cc
+++ b/rtc_base/bit_buffer_unittest.cc
@@ -142,6 +142,38 @@
EXPECT_FALSE(buffer.ReadBits(&val, 1));
}
+TEST(BitBufferTest, ReadBits64) {
+ const uint8_t bytes[] = {0x4D, 0x32, 0xAB, 0x54, 0x00, 0xFF, 0xFE, 0x01,
+ 0xAB, 0xCD, 0xEF, 0x01, 0x23, 0x45, 0x67, 0x89};
+ BitBuffer buffer(bytes, 16);
+ uint64_t val;
+
+ // Peek and read first 33 bits.
+ EXPECT_TRUE(buffer.PeekBits(&val, 33));
+ EXPECT_EQ(0x4D32AB5400FFFE01ull >> (64 - 33), val);
+ val = 0;
+ EXPECT_TRUE(buffer.ReadBits(&val, 33));
+ EXPECT_EQ(0x4D32AB5400FFFE01ull >> (64 - 33), val);
+
+ // Peek and read next 31 bits.
+ constexpr uint64_t kMask31Bits = (1ull << 32) - 1;
+ EXPECT_TRUE(buffer.PeekBits(&val, 31));
+ EXPECT_EQ(0x4D32AB5400FFFE01ull & kMask31Bits, val);
+ val = 0;
+ EXPECT_TRUE(buffer.ReadBits(&val, 31));
+ EXPECT_EQ(0x4D32AB5400FFFE01ull & kMask31Bits, val);
+
+ // Peek and read remaining 64 bits.
+ EXPECT_TRUE(buffer.PeekBits(&val, 64));
+ EXPECT_EQ(0xABCDEF0123456789ull, val);
+ val = 0;
+ EXPECT_TRUE(buffer.ReadBits(&val, 64));
+ EXPECT_EQ(0xABCDEF0123456789ull, val);
+
+ // Nothing more to read.
+ EXPECT_FALSE(buffer.ReadBits(&val, 1));
+}
+
TEST(BitBufferDeathTest, SetOffsetValues) {
uint8_t bytes[4] = {0};
BitBufferWriter buffer(bytes, 4);