ForceTLS: persist to disk

chrome/browser/force_tls_persister.cc

+// Copyright (c) 2006-2008 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 "chrome/browser/force_tls_persister.h"
+
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/message_loop.h"
+#include "base/path_service.h"
+#include "base/thread.h"
+#include "chrome/common/chrome_paths.h"
+#include "net/base/force_tls_state.h"
+
+// Since the ForceTLSState takes a simple C function as the callback, this
+// bounces to the StateIsDirty method of the given object.
+static void StateIsDirtyTrampoline(void* arg) {
+  ForceTLSPersister* persister = reinterpret_cast<ForceTLSPersister*>(arg);
+  persister->StateIsDirty();
+}
+
+ForceTLSPersister::ForceTLSPersister(net::ForceTLSState* state,
+                                     base::Thread* file_thread)
+    : state_is_dirty_(false),
+      force_tls_state_(state),
+      file_thread_(file_thread) {
+  state->SetDirtyCallback(StateIsDirtyTrampoline, this);
+
+  Task* task = NewRunnableMethod(this, &ForceTLSPersister::LoadState);
+  file_thread->message_loop()->PostDelayedTask(FROM_HERE, task,
+                                               1000 /* 1 second */);
+}
+
+static FilePath GetStateFile() {
+  FilePath user_data_dir;
+  PathService::Get(chrome::DIR_USER_DATA, &user_data_dir);
+  return user_data_dir.Append("ForceTLSState");
+}
+
+void ForceTLSPersister::LoadState() {
+  // Runs on |file_thread_|
+  AutoLock locked_(lock_);
+  DCHECK(file_thread_->message_loop() == MessageLoop::current());
+
+  std::string state;
+  if (!file_util::ReadFileToString(GetStateFile(), &state))
+    return;
+
+  force_tls_state_->Deserialise(state);
+}
+
+void ForceTLSPersister::StateIsDirty() {
+  // Runs on arbitary thread, may not block nor reenter |force_tls_state_|
+  AutoLock locked_(lock_);
+
+  if (state_is_dirty_)
+    return;  // we already have a serialisation scheduled
+
+  Task* task = NewRunnableMethod(this, &ForceTLSPersister::SerialiseState);
+  file_thread_->message_loop()->PostDelayedTask(FROM_HERE, task,
+                                                1000 /* 1 second */);
+  state_is_dirty_ = true;
+}
+
+void ForceTLSPersister::SerialiseState() {
+  // Runs on |file_thread_|
+  AutoLock locked_(lock_);
+  DCHECK(file_thread_->message_loop() == MessageLoop::current());
+
+  DCHECK(state_is_dirty_);
+  state_is_dirty_ = false;
+
+  std::string state;
+  if (!force_tls_state_->Serialise(&state))
+    return;
+
+  file_util::WriteFile(GetStateFile(), state.data(), state.size());
+}