OEMCrypto Profiler

This CL is a merge from the widevine repo of:
http://go/wvgerrit/16491 Circular Buffer
http://go/wvgerrit/16512 Circular Buffer Tests
http://go/wvgerrit/16493 Entry Writer
http://go/wvgerrit/16495 Profiled Scope
http://go/wvgerrit/16500 Stats Collection
http://go/wvgerrit/16543 Disallow Stats Copy or Assign
http://go/wvgerrit/16514 Moving OEM Function Enum
http://go/wvgerrit/16501 Defining Session Interface
http://go/wvgerrit/16502 Session Definitions
http://go/wvgerrit/16573 Remove code to num bytes table
http://go/wvgerrit/16556 Connecting Profiler to Profiled Scope
http://go/wvgerrit/16557 Android Reading Profiler History
http://go/wvgerrit/16574 Adding Get Stats Method
http://go/wvgerrit/16606 Seperating Session Parsing
http://go/wvgerrit/16607 Adding get stats method to DRMPlugin
http://go/wvgerrit/16608 Fixing Linux Build Failure
http://go/wvgerrit/16612 Stop Clearing History
http://go/wvgerrit/16613 Accessing profiler information using session id
http://go/wvgerrit/16614 Making All Session Subsets of Global Session

BUG: 25123303
BUG: 26027857
Change-Id: Ie2422e644aa631871852ea0e461695aeb7060f88

libwvdrmengine/cdm/profiler/include/profiler_session.h

@@ -0,0 +1,73 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+
+#ifndef WVCDM_PROFILER_SESSION_H_
+#define WVCDM_PROFILER_SESSION_H_
+
+#include <map>
+#include <stddef.h>
+#include <stdint.h>
+#include <vector>
+
+#include "circular_buffer.h"
+#include "entry_writer.h"
+#include "oem_functions.h"
+#include "stats.h"
+
+namespace wvcdm {
+namespace oemprofiler {
+
+class ProfilerSession {
+
+ public:
+  ProfilerSession();
+
+  void Submit(
+      OEM_FUNCTION fid,
+      uint64_t start_time,
+      uint64_t end_time,
+      const uint8_t* meta_data,
+      size_t meta_data_length);
+
+  // clear all samples and stats
+  void Clear();
+
+  void ReadHistory(std::vector<uint8_t>& output) const;
+
+  void ReadAllStats(std::vector<uint8_t>& output) const;
+  const Stat& ReadStat(OEM_FUNCTION fid) const;
+
+  static void Open(int64_t sid);
+  static void Close(int64_t sid);
+
+  static ProfilerSession* Find(int64_t sid);
+
+ private:
+  Stat stats_[OEM_FUNCTION_COUNT];
+
+  CircularBuffer buffer_;
+
+  uint64_t time_at_head_;
+  uint64_t time_at_tail_;
+
+  bool RequestSpace(uint8_t num_bytes);
+
+  bool ReadNextEntryRealEndTime(uint64_t* output);
+
+  bool DropLastEntry();
+
+  // Read a variable length value. This is the read that matches
+  // EntryWriter's WriteVLV.
+  int ReadVLV(size_t offset, uint64_t* output) const;
+
+  ProfilerSession(const ProfilerSession&);
+  void operator=(const ProfilerSession&);
+
+  static uint8_t GetByte(uint64_t value, size_t byte_index);
+
+  static std::map<int64_t, ProfilerSession*> sessions_;
+};
+
+}  // namespace oemprofiler
+}  // namespace wvcdm
+
+#endif