Port WebSockets to Mojo IPC

content/browser/websockets/websocket_manager.cc

+// Copyright 2013 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 "content/browser/websockets/websocket_manager.h"
+
+#include <stddef.h>
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
+#include "base/rand_util.h"
+#include "base/stl_util.h"
+#include "content/public/browser/browser_thread.h"
+#include "net/url_request/url_request_context_getter.h"
+
+namespace content {
+
+namespace {
+
+// Max number of pending connections per WebSocketManager used for per-renderer
+// WebSocket throttling.
+const int kMaxPendingWebSocketConnections = 255;
+
+}  // namespace
+
+WebSocketManager::WebSocketManager(int process_id,
+                                   StoragePartition* storage_partition)
+    : process_id_(process_id),
+      storage_partition_(storage_partition),
+      num_pending_connections_(0),
+      num_current_succeeded_connections_(0),
+      num_previous_succeeded_connections_(0),
+      num_current_failed_connections_(0),
+      num_previous_failed_connections_(0) {}
+
+WebSocketManager::~WebSocketManager() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  for (auto impl : impls_) {
+    impl->GoAway();
+    delete impl;
+  }
+}
+
+void WebSocketManager::CreateWebSocket(int render_frame_id,
+                                       mojom::WebSocketRequest request) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  if (num_pending_connections_ >= kMaxPendingWebSocketConnections) {
+    // Too many websockets! By returning here, we let |request| die, which
+    // will be observed by the client as Mojo connection error.
+    return;
+  }
+
+  // Keep all WebSocketImpls alive until either the client drops its
+  // connection (see OnLostConnectionToClient) or we need to shutdown.
+
+  impls_.insert(new WebSocketImpl(this,
+                                  std::move(request),
+                                  render_frame_id,
+                                  CalculateDelay()));
+  ++num_pending_connections_;
+
+  if (!throttling_period_timer_.IsRunning()) {
+    throttling_period_timer_.Start(
+        FROM_HERE,
+        base::TimeDelta::FromMinutes(2),
+        this,
+        &WebSocketManager::ThrottlingPeriodTimerCallback);
+  }
+}
+
+// Calculate delay as described in the per-renderer WebSocket throttling
+// design doc: https://goo.gl/tldFNn
+base::TimeDelta WebSocketManager::CalculateDelay() const {
+  int64_t f = num_previous_failed_connections_ +
+              num_current_failed_connections_;
+  int64_t s = num_previous_succeeded_connections_ +
+              num_current_succeeded_connections_;
+  int p = num_pending_connections_;
+  return base::TimeDelta::FromMilliseconds(
+      base::RandInt(1000, 5000) *
+      (1 << std::min(p + f / (s + 1), INT64_C(16))) / 65536);
+}
+
+void WebSocketManager::ThrottlingPeriodTimerCallback() {
+  num_previous_failed_connections_ = num_current_failed_connections_;
+  num_current_failed_connections_ = 0;
+
+  num_previous_succeeded_connections_ = num_current_succeeded_connections_;
+  num_current_succeeded_connections_ = 0;
+
+  if (num_pending_connections_ == 0 &&
+      num_previous_failed_connections_ == 0 &&
+      num_previous_succeeded_connections_ == 0) {
+    throttling_period_timer_.Stop();
+  }
+}
+
+int WebSocketManager::GetClientProcessId() {
+  return process_id_;
+}
+
+StoragePartition* WebSocketManager::GetStoragePartition() {
+  return storage_partition_;
+}
+
+void WebSocketManager::OnReceivedResponseFromServer(WebSocketImpl* impl) {
+  // The server accepted this WebSocket connection.
+  impl->OnHandshakeSucceeded();
+  --num_pending_connections_;
+  DCHECK_GE(num_pending_connections_, 0);
+  ++num_current_succeeded_connections_;
+}
+
+void WebSocketManager::OnLostConnectionToClient(WebSocketImpl* impl) {
+  // The client is no longer interested in this WebSocket.
+  if (!impl->handshake_succeeded()) {
+    // Update throttling counters (failure).
+    --num_pending_connections_;
+    DCHECK_GE(num_pending_connections_, 0);
+    ++num_current_failed_connections_;
+  }
+  impls_.erase(impl);
+  delete impl;
+}
+
+}  // namespace content