1 files changed, 147 insertions, 0 deletions
diff --git a/security/sandbox/chromium/base/threading/thread_id_name_manager.cc b/security/sandbox/chromium/base/threading/thread_id_name_manager.cc
new file mode 100644
index 0000000000..ba2f9b41cb
--- /dev/null
+++ b/security/sandbox/chromium/base/threading/thread_id_name_manager.cc
@@ -0,0 +1,147 @@
+// Copyright (c) 2012 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 "base/threading/thread_id_name_manager.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "base/logging.h"
+#include "base/memory/singleton.h"
+#include "base/no_destructor.h"
+#include "base/stl_util.h"
+#include "base/strings/string_util.h"
+#include "base/threading/thread_local.h"
+#include "base/trace_event/heap_profiler_allocation_context_tracker.h"
+
+namespace base {
+namespace {
+
+static const char kDefaultName[] = "";
+static std::string* g_default_name;
+
+ThreadLocalStorage::Slot& GetThreadNameTLS() {
+  static base::NoDestructor<base::ThreadLocalStorage::Slot> thread_name_tls;
+  return *thread_name_tls;
+}
+}
+
+ThreadIdNameManager::Observer::~Observer() = default;
+
+ThreadIdNameManager::ThreadIdNameManager()
+    : main_process_name_(nullptr), main_process_id_(kInvalidThreadId) {
+  g_default_name = new std::string(kDefaultName);
+
+  AutoLock locked(lock_);
+  name_to_interned_name_[kDefaultName] = g_default_name;
+}
+
+ThreadIdNameManager::~ThreadIdNameManager() = default;
+
+ThreadIdNameManager* ThreadIdNameManager::GetInstance() {
+  return Singleton<ThreadIdNameManager,
+      LeakySingletonTraits<ThreadIdNameManager> >::get();
+}
+
+const char* ThreadIdNameManager::GetDefaultInternedString() {
+  return g_default_name->c_str();
+}
+
+void ThreadIdNameManager::RegisterThread(PlatformThreadHandle::Handle handle,
+                                         PlatformThreadId id) {
+  AutoLock locked(lock_);
+  thread_id_to_handle_[id] = handle;
+  thread_handle_to_interned_name_[handle] =
+      name_to_interned_name_[kDefaultName];
+}
+
+void ThreadIdNameManager::AddObserver(Observer* obs) {
+  AutoLock locked(lock_);
+  DCHECK(!base::Contains(observers_, obs));
+  observers_.push_back(obs);
+}
+
+void ThreadIdNameManager::RemoveObserver(Observer* obs) {
+  AutoLock locked(lock_);
+  DCHECK(base::Contains(observers_, obs));
+  base::Erase(observers_, obs);
+}
+
+void ThreadIdNameManager::SetName(const std::string& name) {
+  PlatformThreadId id = PlatformThread::CurrentId();
+  std::string* leaked_str = nullptr;
+  {
+    AutoLock locked(lock_);
+    auto iter = name_to_interned_name_.find(name);
+    if (iter != name_to_interned_name_.end()) {
+      leaked_str = iter->second;
+    } else {
+      leaked_str = new std::string(name);
+      name_to_interned_name_[name] = leaked_str;
+    }
+
+    auto id_to_handle_iter = thread_id_to_handle_.find(id);
+
+    GetThreadNameTLS().Set(const_cast<char*>(leaked_str->c_str()));
+    for (Observer* obs : observers_)
+      obs->OnThreadNameChanged(leaked_str->c_str());
+
+    // The main thread of a process will not be created as a Thread object which
+    // means there is no PlatformThreadHandler registered.
+    if (id_to_handle_iter == thread_id_to_handle_.end()) {
+      main_process_name_ = leaked_str;
+      main_process_id_ = id;
+      return;
+    }
+    thread_handle_to_interned_name_[id_to_handle_iter->second] = leaked_str;
+  }
+
+  // Add the leaked thread name to heap profiler context tracker. The name added
+  // is valid for the lifetime of the process. AllocationContextTracker cannot
+  // call GetName(which holds a lock) during the first allocation because it can
+  // cause a deadlock when the first allocation happens in the
+  // ThreadIdNameManager itself when holding the lock.
+  trace_event::AllocationContextTracker::SetCurrentThreadName(
+      leaked_str->c_str());
+}
+
+const char* ThreadIdNameManager::GetName(PlatformThreadId id) {
+  AutoLock locked(lock_);
+
+  if (id == main_process_id_)
+    return main_process_name_->c_str();
+
+  auto id_to_handle_iter = thread_id_to_handle_.find(id);
+  if (id_to_handle_iter == thread_id_to_handle_.end())
+    return name_to_interned_name_[kDefaultName]->c_str();
+
+  auto handle_to_name_iter =
+      thread_handle_to_interned_name_.find(id_to_handle_iter->second);
+  return handle_to_name_iter->second->c_str();
+}
+
+const char* ThreadIdNameManager::GetNameForCurrentThread() {
+  const char* name = reinterpret_cast<const char*>(GetThreadNameTLS().Get());
+  return name ? name : kDefaultName;
+}
+
+void ThreadIdNameManager::RemoveName(PlatformThreadHandle::Handle handle,
+                                     PlatformThreadId id) {
+  AutoLock locked(lock_);
+  auto handle_to_name_iter = thread_handle_to_interned_name_.find(handle);
+
+  DCHECK(handle_to_name_iter != thread_handle_to_interned_name_.end());
+  thread_handle_to_interned_name_.erase(handle_to_name_iter);
+
+  auto id_to_handle_iter = thread_id_to_handle_.find(id);
+  DCHECK((id_to_handle_iter!= thread_id_to_handle_.end()));
+  // The given |id| may have been re-used by the system. Make sure the
+  // mapping points to the provided |handle| before removal.
+  if (id_to_handle_iter->second != handle)
+    return;
+
+  thread_id_to_handle_.erase(id_to_handle_iter);
+}
+
+}  // namespace base