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 <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 "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_process_host.h"
+
+namespace content {
+
+namespace {
+
+const char kWebSocketManagerKeyName[] = "web_socket_manager";
+
+// Max number of pending connections per WebSocketManager used for per-renderer
+// WebSocket throttling.
+const int kMaxPendingWebSocketConnections = 255;
+
+}  // namespace
+
+class WebSocketManager::Handle : public base::SupportsUserData::Data {
+ public:
+  explicit Handle(WebSocketManager* manager) : manager_(manager) {}
+
+  ~Handle() override {
+    BrowserThread::DeleteSoon(BrowserThread::IO, FROM_HERE, manager_);
+  }
+
+  WebSocketManager* manager() const { return manager_; }
+
+ private:
+  WebSocketManager* manager_;
+};
+
+// static
+void WebSocketManager::CreateWebSocket(int process_id,
+                                       mojom::WebSocketRequest request) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  RenderProcessHost* host = RenderProcessHost::FromID(process_id);
+  CHECK(host);
+
+  Handle* handle =
+      static_cast<Handle*>(host->GetUserData(kWebSocketManagerKeyName));
+  if (!handle) {
+    handle = new Handle(
+        new WebSocketManager(process_id, host->GetStoragePartition()));
+    host->SetUserData(kWebSocketManagerKeyName, handle);
+  }
+
+  BrowserThread::PostTask(
+      BrowserThread::IO,
+      FROM_HERE,
+      base::Bind(&WebSocketManager::DoCreateWebSocket,
+                 base::Unretained(handle->manager()),
+                 base::Passed(&request)));
+}
+
+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::DoCreateWebSocket(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(
+      CreateWebSocketImpl(this, std::move(request), 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();
+  }
+}
+
+WebSocketImpl* WebSocketManager::CreateWebSocketImpl(
+    WebSocketImpl::Delegate* delegate,
+    mojom::WebSocketRequest request,
+    base::TimeDelta delay) {
+  return new WebSocketImpl(delegate, std::move(request), delay);
+}
+
+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_;
+  }
+  impl->GoAway();
+  impls_.erase(impl);
+  delete impl;
+}
+
+}  // namespace content