media: Add experimental feature to enable Mojo CDM on desktop Chromium

media/cdm/cdm_adapter_factory.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/cdm/cdm_adapter_factory.h"
+
+#include "base/base_paths.h"
+#include "base/bind.h"
+#include "base/feature_list.h"
+#include "base/memory/ptr_util.h"
+#include "base/path_service.h"
+#include "base/threading/thread_task_runner_handle.h"
+#include "media/base/cdm_factory.h"
+#include "media/base/key_systems.h"
+#include "media/cdm/cdm_adapter.h"
+#include "media/cdm/cdm_paths.h"
+#include "third_party/widevine/cdm/widevine_cdm_common.h"
+
+namespace media {
+
+CdmAdapterFactory::CdmAdapterFactory(
+    CdmAllocator::CreationCB allocator_creation_cb)
+    : allocator_creation_cb_(std::move(allocator_creation_cb)) {
+  DCHECK(allocator_creation_cb_);
+}
+
+CdmAdapterFactory::~CdmAdapterFactory() {}
+
+void CdmAdapterFactory::Create(
+    const std::string& key_system,
+    const GURL& security_origin,
+    const CdmConfig& cdm_config,
+    const SessionMessageCB& session_message_cb,
+    const SessionClosedCB& session_closed_cb,
+    const SessionKeysChangeCB& session_keys_change_cb,
+    const SessionExpirationUpdateCB& session_expiration_update_cb,
+    const CdmCreatedCB& cdm_created_cb) {
+  DVLOG(1) << __FUNCTION__ << ": key_system=" << key_system;
+
+  if (!security_origin.is_valid()) {
+    LOG(ERROR) << "Invalid Origin: " << security_origin;
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(cdm_created_cb, nullptr, "Invalid origin."));
+    return;
+  }
+
+  base::FilePath cdm_path;
+
+#if defined(WIDEVINE_CDM_AVAILABLE)
+  // TODO(xhwang): Remove key-system-specific logic here. We should have the
+  // CDM path forwarded from the browser already. See http://crbug.com/510604
+  if (key_system == kWidevineKeySystem) {
+    // Build the library path for Widevine CDM.
+    // TODO(xhwang): We should have the CDM path forwarded from the browser
+    // already. See http://crbug.com/510604
+    base::FilePath cdm_base_path;
+    base::PathService::Get(base::DIR_MODULE, &cdm_base_path);
+    cdm_base_path = cdm_base_path.Append(
+        GetPlatformSpecificDirectory(kWidevineCdmBaseDirectory));
+    cdm_path = cdm_base_path.AppendASCII(
+        base::GetNativeLibraryName(kWidevineCdmLibraryName));
+  }
+#endif  // defined(WIDEVINE_CDM_AVAILABLE)
+
+  if (cdm_path.empty()) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE,
+        base::Bind(cdm_created_cb, nullptr, "Unsupported key system."));
+    return;
+  }
+
+  std::unique_ptr<CdmAllocator> cdm_allocator = allocator_creation_cb_.Run();
+  if (!cdm_allocator) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE,
+        base::Bind(cdm_created_cb, nullptr, "CDM allocator creation failed."));
+    return;
+  }
+
+  // TODO(xhwang): Hook up auxiliary services, e.g. File IO, output protection,
+  // and platform verification.
+  CdmAdapter::Create(key_system, cdm_path, cdm_config, std::move(cdm_allocator),
+                     CreateCdmFileIOCB(), session_message_cb, session_closed_cb,
+                     session_keys_change_cb, session_expiration_update_cb,
+                     cdm_created_cb);
+}
+
+}  // namespace media