Store key set ID with usage info

[ Merge of http://go/wvgerrit/16241 and http://go/wvgerrit/16364 ]

This will allow a usage session to be loaded later by key set ID.
This is needed for EME-style secure stop in the new CE CDM API.

b/25816911

Change-Id: I916340047492fbc0556d0e90bd2eac0f3eafe597

libwvdrmengine/cdm/core/src/cdm_engine.cpp

@@ -2,6 +2,7 @@
 
 #include "cdm_engine.h"
 
+#include <assert.h>
 #include <stdlib.h>
 
 #include <iostream>
@@ -934,6 +935,66 @@ CdmResponseType CdmEngine::ReleaseUsageInfo(
   return status;
 }
 
+CdmResponseType CdmEngine::LoadUsageSession(const CdmKeySetId& key_set_id,
+                                            CdmKeyMessage* release_message) {
+  LOGI("CdmEngine::LoadUsageSession");
+  // This method is currently only used by the CE CDM, in which all session IDs
+  // are key set IDs.
+  assert(Properties::AlwaysUseKeySetIds());
+
+  if (key_set_id.empty()) {
+    LOGE("CdmEngine::LoadUsageSession: invalid key set id");
+    return EMPTY_KEYSET_ID_ENG_5;
+  }
+
+  CdmSessionMap::iterator iter = sessions_.find(key_set_id);
+  if (iter == sessions_.end()) {
+    LOGE("CdmEngine::LoadUsageSession: session_id not found = %s ",
+         key_set_id.c_str());
+    return SESSION_NOT_FOUND_11;
+  }
+
+  DeviceFiles handle;
+  if (!handle.Init(iter->second->GetSecurityLevel())) {
+    LOGE("CdmEngine::LoadUsageSession: unable to initialize device files");
+    return LOAD_USAGE_INFO_FILE_ERROR;
+  }
+
+  std::string app_id;
+  iter->second->GetApplicationId(&app_id);
+
+  CdmKeyMessage key_message;
+  CdmKeyResponse key_response;
+  if (!handle.RetrieveUsageInfoByKeySetId(app_id, key_set_id, &key_message,
+                                          &key_response)) {
+    LOGE("CdmEngine::LoadUsageSession: unable to find usage information");
+    return LOAD_USAGE_INFO_MISSING;
+  }
+
+  CdmResponseType status =
+      iter->second->RestoreUsageSession(key_message, key_response);
+  if (KEY_ADDED != status) {
+    LOGE("CdmEngine::LoadUsageSession: usage session error %ld", status);
+    return status;
+  }
+
+  std::string server_url;
+  status = iter->second->GenerateReleaseRequest(release_message, &server_url);
+
+  switch (status) {
+    case KEY_MESSAGE:
+      break;
+    case KEY_CANCELED:                // usage information not present in
+      iter->second->DeleteLicense();  // OEMCrypto, delete and try again
+      break;
+    default:
+      LOGE("CdmEngine::LoadUsageSession: generate release request error: %d",
+           status);
+      break;
+  }
+  return status;
+}
+
 CdmResponseType CdmEngine::Decrypt(const CdmSessionId& session_id,
                                    const CdmDecryptionParameters& parameters) {
   if (parameters.key_id == NULL) {