diff options
Diffstat (limited to 'base/metrics/histogram_unittest.cc')
| -rw-r--r-- | base/metrics/histogram_unittest.cc | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/base/metrics/histogram_unittest.cc b/base/metrics/histogram_unittest.cc index b9c51ad..afa69a6 100644 --- a/base/metrics/histogram_unittest.cc +++ b/base/metrics/histogram_unittest.cc @@ -348,7 +348,8 @@ TEST(HistogramTest, CorruptBucketBounds) { EXPECT_EQ(0, histogram->FindCorruption(snapshot)); // No default corruption. std::swap(histogram->ranges_[1], histogram->ranges_[2]); - EXPECT_EQ(Histogram::BUCKET_ORDER_ERROR, histogram->FindCorruption(snapshot)); + EXPECT_EQ(Histogram::BUCKET_ORDER_ERROR | Histogram::RANGE_CHECKSUM_ERROR, + histogram->FindCorruption(snapshot)); std::swap(histogram->ranges_[1], histogram->ranges_[2]); EXPECT_EQ(0, histogram->FindCorruption(snapshot)); @@ -357,8 +358,30 @@ TEST(HistogramTest, CorruptBucketBounds) { EXPECT_EQ(Histogram::RANGE_CHECKSUM_ERROR, histogram->FindCorruption(snapshot)); + // Show that two simple changes don't offset each other + --histogram->ranges_[4]; + EXPECT_EQ(Histogram::RANGE_CHECKSUM_ERROR, + histogram->FindCorruption(snapshot)); + // Repair histogram so that destructor won't DCHECK(). --histogram->ranges_[3]; + ++histogram->ranges_[4]; +} + +// Table was generated similarly to sample code for CRC-32 given on: +// http://www.w3.org/TR/PNG/#D-CRCAppendix. +TEST(HistogramTest, Crc32TableTest) { + for (int i = 0; i < 256; ++i) { + uint32 checksum = i; + for (int j = 0; j < 8; ++j) { + const uint32 kReversedPolynomial = 0xedb88320L; + if (checksum & 1) + checksum = kReversedPolynomial ^ (checksum >> 1); + else + checksum >>= 1; + } + EXPECT_EQ(Histogram::kCrcTable[i], checksum); + } } } // namespace base |