OEMCrypto Profiler - Merge of Widevine Updates

This change is a merge of the following changes:
1. Remove MultipleSessions (go/wvgerrit/16763)
2. Increase Memory Budget (go/wvgerrit/16764)
3. Fixing Possible Integer Overflow (go/wvgerrit/16765)
4. Creating Call Table (go/wvgerrit/16766)
5. Creating Call History (go/wvgerrit/16767)
6. Connecting Profiled Scope (go/wvgerrit/16768)
7. Adding Call Table Version Number (go/wvgerrit/16780)
8. Add Version Number to Call History (go/wvgerrit/16781)

bug: 27157796

Change-Id: Ia3f088a1714f3f5b426fee6141daa4ea8d832cf4

libwvdrmengine/cdm/profiler/src/call_table.cpp

@@ -0,0 +1,103 @@
+#include "call_table.h"
+
+#include <limits>
+
+#include "entry_writer.h"
+
+namespace wvcdm {
+namespace oemprofiler {
+
+namespace {
+  const uint8_t kOutputVersionNumber = 0x00;
+}
+
+CallTable::Row::Row() :
+    min_(std::numeric_limits<uint64_t>::max()),
+    max_(0),
+    sample_size_(0),
+    mean_(0),
+    variance_m_(0),
+    variance_s_(0) {
+
+}
+
+void CallTable::Row::Add(uint64_t value) {
+  min_ = std::min(min_, value);
+  max_ = std::max(max_, value);
+
+  mean_ = ((mean_ * sample_size_) + value) / (sample_size_ + 1.0);
+  sample_size_ += 1;
+
+  // Welford's method for standard deviation and variance
+  const double old_m = variance_m_;
+  const double old_s = variance_s_;
+  variance_m_ = old_m + (value - old_m) / sample_size_;
+  variance_s_ = old_s + (value - variance_m_) * (value -old_m);
+}
+
+uint64_t CallTable::Row::GetSampleSize() const {
+  return sample_size_;
+}
+
+uint64_t CallTable::Row::GetMin() const {
+  return min_;
+}
+
+uint64_t CallTable::Row::GetMax() const {
+  return max_;
+}
+
+double CallTable::Row::GetMean() const {
+  return mean_;
+}
+
+double CallTable::Row::GetVariance() const {
+  return sample_size_ > 1 ? variance_s_ / (sample_size_ - 1) : 0;
+}
+
+const CallTable::Row* CallTable::LookUp(uint64_t row_id) const {
+  return map_.count(row_id) == 0 ? NULL : &map_.find(row_id)->second;
+}
+
+void CallTable::Write(uint64_t row_id, uint64_t sample) {
+  if (map_.count(row_id) == 0) {
+     map_.insert(std::pair<uint64_t, Row>(row_id, Row()));
+  }
+
+  map_[row_id].Add(sample);
+}
+
+void CallTable::Read(std::vector<uint8_t>& output) const {
+  output.push_back(kOutputVersionNumber);
+
+  for (std::map<uint64_t, Row>::const_iterator it = map_.begin();
+      it != map_.end(); ++it) {
+
+    const uint64_t values_to_write[] = {
+      it->first,
+      it->second.GetSampleSize(),
+      it->second.GetMin(),
+      it->second.GetMax(),
+      static_cast<uint64_t>(it->second.GetMean()),
+      // get the decimal places to the one-hundredths
+      static_cast<uint64_t>(it->second.GetMean() * 100) % 100,
+      static_cast<uint64_t>(it->second.GetVariance()),
+      // get the decimal places to the one-hundredths
+      static_cast<uint64_t>(it->second.GetVariance() * 100) % 100
+    };
+
+    const size_t kValuesToWriteSize = 8;
+
+    for (size_t i = 0; i < kValuesToWriteSize; i++) {
+      EntryWriter writer;
+      writer.WriteVLV(values_to_write[i]);
+
+      for (size_t w_i = 0; w_i < writer.GetSize(); w_i++) {
+        output.push_back(writer.GetData()[w_i]);
+      }
+    }
+  }
+}
+
+}  // namespace oemprofiler
+}  // namespace wvcdm