Replace generic OnEvent with actual event callbacks

Also pass session_id and event_listener to PolicyEngine to make it easier
to dispatch events from PolicyEngine.

Bug: 19771437

Merged from Widevine CDM repo:
https://widevine-internal-review.googlesource.com/#/c/13816/

Change-Id: I5723cb371cb3c43c945051af3402b09069ba5859

libwvdrmengine/cdm/core/include/policy_engine.h

@@ -16,12 +16,14 @@ using video_widevine_server::sdk::LicenseIdentification;
 
 class Clock;
 class CryptoSession;
+class WvCdmEventListener;
 
 // This acts as an oracle that basically says "Yes(true) you may still decrypt
 // or no(false) you may not decrypt this data anymore."
 class PolicyEngine {
  public:
-  explicit PolicyEngine(CryptoSession* crypto_session);
+  PolicyEngine(CdmSessionId session_id, WvCdmEventListener* event_listener,
+               CryptoSession* crypto_session);
   virtual ~PolicyEngine();
 
   // The value returned should be taken as a hint rather than an absolute
@@ -32,11 +34,9 @@ class PolicyEngine {
   virtual bool CanDecrypt(const KeyId& key_id);
 
   // OnTimerEvent is called when a timer fires. It notifies the Policy Engine
-  // that the timer has fired and that it should check whether any events have
-  // occurred since the last timer event. If so, it sets event_occurred to true
-  // and sets event to point to the event that occurred. If not, it sets
-  // event_occurred to false.
-  virtual void OnTimerEvent(bool* event_occurred, CdmEventType* event);
+  // that the timer has fired and dispatches the relevant events through
+  // |event_listener_|.
+  virtual void OnTimerEvent();
 
   // SetLicense is used in handling the initial license response. It stores
   // an exact copy of the policy information stored in the license.
@@ -126,6 +126,10 @@ class PolicyEngine {
   int64_t next_renewal_time_;
   int64_t policy_max_duration_seconds_;
 
+  // Used to dispatch CDM events.
+  CdmSessionId session_id_;
+  WvCdmEventListener* event_listener_;
+
   MaxResEngine max_res_engine_;
   scoped_ptr<Clock> clock_;
 

libwvdrmengine/cdm/core/include/wv_cdm_event_listener.h

@@ -13,8 +13,8 @@ class WvCdmEventListener {
   WvCdmEventListener() {}
   virtual ~WvCdmEventListener() {}
 
-  virtual void OnEvent(const CdmSessionId& session_id,
-                       CdmEventType cdm_event) = 0;
+  virtual void OnSessionRenewalNeeded(const CdmSessionId& session_id) = 0;
+  virtual void OnSessionExpiration(const CdmSessionId& session_id) = 0;
 
  private:
   CORE_DISALLOW_COPY_AND_ASSIGN(WvCdmEventListener);

libwvdrmengine/cdm/core/include/wv_cdm_types.h

@@ -53,11 +53,6 @@ enum CdmResponseType {
   TypeName(const TypeName&);                    \
   void operator=(const TypeName&)
 
-enum CdmEventType {
-  LICENSE_EXPIRED_EVENT,
-  LICENSE_RENEWAL_NEEDED_EVENT
-};
-
 enum CdmLicenseType {
   kLicenseTypeOffline,
   kLicenseTypeStreaming,

libwvdrmengine/cdm/core/src/cdm_session.cpp

@@ -30,7 +30,8 @@ CdmSession::CdmSession(const CdmClientPropertySet* cdm_client_property_set,
       event_listener_(event_listener),
       license_parser_(new CdmLicense),
       crypto_session_(new CryptoSession),
-      policy_engine_(new PolicyEngine(crypto_session_.get())),
+      policy_engine_(new PolicyEngine(session_id_, event_listener_,
+                                      crypto_session_.get())),
       file_handle_(new DeviceFiles),
       license_received_(false),
       is_offline_(false),
@@ -519,9 +520,6 @@ void CdmSession::NotifyResolution(uint32_t width, uint32_t height) {
 }
 
 void CdmSession::OnTimerEvent(bool update_usage) {
-  bool event_occurred = false;
-  CdmEventType event;
-
   if (update_usage && has_decrypted_since_last_report_) {
     policy_engine_->DecryptionEvent();
     has_decrypted_since_last_report_ = false;
@@ -529,17 +527,12 @@ void CdmSession::OnTimerEvent(bool update_usage) {
       StoreLicense(DeviceFiles::kLicenseStateActive);
     }
   }
-  policy_engine_->OnTimerEvent(&event_occurred, &event);
-
-  if (event_occurred) {
-    if (event_listener_) event_listener_->OnEvent(session_id_, event);
-  }
+  policy_engine_->OnTimerEvent();
 }
 
 void CdmSession::OnKeyReleaseEvent(const CdmKeySetId& key_set_id) {
   if (key_set_id_ == key_set_id) {
-    if (event_listener_)
-      event_listener_->OnEvent(session_id_, LICENSE_EXPIRED_EVENT);
+    if (event_listener_) event_listener_->OnSessionExpiration(session_id_);
   }
 }
 

libwvdrmengine/cdm/core/src/policy_engine.cpp

@@ -13,10 +13,13 @@
 #include "properties.h"
 #include "string_conversions.h"
 #include "wv_cdm_constants.h"
+#include "wv_cdm_event_listener.h"
 
 namespace wvcdm {
 
-PolicyEngine::PolicyEngine(CryptoSession* crypto_session)
+PolicyEngine::PolicyEngine(CdmSessionId session_id,
+                           WvCdmEventListener* event_listener,
+                           CryptoSession* crypto_session)
     : license_state_(kLicenseStateInitial),
       can_decrypt_(false),
       license_start_time_(0),
@@ -24,6 +27,8 @@ PolicyEngine::PolicyEngine(CryptoSession* crypto_session)
       last_playback_time_(0),
       next_renewal_time_(0),
       policy_max_duration_seconds_(0),
+      session_id_(session_id),
+      event_listener_(event_listener),
       max_res_engine_(crypto_session),
       clock_(new Clock) {}
 
@@ -33,8 +38,7 @@ bool PolicyEngine::CanDecrypt(const KeyId& key_id) {
   return can_decrypt_ && max_res_engine_.CanDecrypt(key_id);
 }
 
-void PolicyEngine::OnTimerEvent(bool* event_occurred, CdmEventType* event) {
-  *event_occurred = false;
+void PolicyEngine::OnTimerEvent() {
   int64_t current_time = clock_->GetCurrentTime();
 
   // License expiration trumps all.
@@ -43,8 +47,7 @@ void PolicyEngine::OnTimerEvent(bool* event_occurred, CdmEventType* event) {
       license_state_ != kLicenseStateExpired) {
     license_state_ = kLicenseStateExpired;
     can_decrypt_ = false;
-    *event = LICENSE_EXPIRED_EVENT;
-    *event_occurred = true;
+    if (event_listener_) event_listener_->OnSessionExpiration(session_id_);
     return;
   }
 
@@ -89,8 +92,7 @@ void PolicyEngine::OnTimerEvent(bool* event_occurred, CdmEventType* event) {
 
   if (renewal_needed) {
     UpdateRenewalRequest(current_time);
-    *event = LICENSE_RENEWAL_NEEDED_EVENT;
-    *event_occurred = true;
+    if (event_listener_) event_listener_->OnSessionRenewalNeeded(session_id_);
   }
 
   max_res_engine_.OnTimerEvent();

libwvdrmengine/cdm/core/test/cdm_session_unittest.cpp

@@ -114,7 +114,7 @@ class MockCryptoSession : public CryptoSession {
 
 class MockPolicyEngine : public PolicyEngine {
  public:
-  MockPolicyEngine() : PolicyEngine(NULL) {}
+  MockPolicyEngine() : PolicyEngine("mock_session_id", NULL, NULL) {}
 
   // Leaving a place-holder for when PolicyEngine methods need to be mocked
 };

libwvdrmengine/cdm/core/test/license_unittest.cpp

@@ -106,7 +106,8 @@ class MockCryptoSession : public CryptoSession {
 
 class MockPolicyEngine : public PolicyEngine {
  public:
-  MockPolicyEngine(CryptoSession* crypto) : PolicyEngine(crypto) {}
+  MockPolicyEngine(CryptoSession* crypto)
+      : PolicyEngine("mock_session_id", NULL, crypto) {}
 };
 
 class MockClock : public Clock {

libwvdrmengine/cdm/core/test/test_printers.cpp

@@ -34,18 +34,6 @@ void PrintTo(const enum CdmResponseType& value, ::std::ostream* os) {
   }
 }
 
-void PrintTo(const enum CdmEventType& value, ::std::ostream* os) {
-  switch (value) {
-    case LICENSE_EXPIRED_EVENT: *os         << "LICENSE_EXPIRED_EVENT";
-      break;
-    case LICENSE_RENEWAL_NEEDED_EVENT: *os  << "LICENSE_RENEWAL_NEEDED_EVENT";
-      break;
-    default:
-      *os                                   << "Unknown  CdmEventType";
-      break;
-  }
-};
-
 void PrintTo(const enum CdmLicenseType& value, ::std::ostream* os) {
   switch (value) {
     case kLicenseTypeOffline: *os           << "kLicenseTypeOffline";

libwvdrmengine/cdm/core/test/test_printers.h

@@ -10,7 +10,6 @@
 
 namespace wvcdm {
 void PrintTo(const enum CdmResponseType& value, ::std::ostream* os);
-void PrintTo(const enum CdmEventType& value, ::std::ostream* os);
 void PrintTo(const enum CdmLicenseType& value, ::std::ostream* os);
 void PrintTo(const enum CdmSecurityLevel& value, ::std::ostream* os);
 void PrintTo(const enum CdmCertificateType& value, ::std::ostream* os);