michael@0: // Copyright (c) 2012 The Chromium Authors. All rights reserved.
michael@0: // Use of this source code is governed by a BSD-style license that can be
michael@0: // found in the LICENSE file.
michael@0: 
michael@0: #include "base/threading/thread_restrictions.h"
michael@0: 
michael@0: #if ENABLE_THREAD_RESTRICTIONS
michael@0: 
michael@0: #include "base/lazy_instance.h"
michael@0: #include "base/logging.h"
michael@0: #include "base/threading/thread_local.h"
michael@0: 
michael@0: namespace base {
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: LazyInstance<ThreadLocalBoolean>::Leaky
michael@0:     g_io_disallowed = LAZY_INSTANCE_INITIALIZER;
michael@0: 
michael@0: LazyInstance<ThreadLocalBoolean>::Leaky
michael@0:     g_singleton_disallowed = LAZY_INSTANCE_INITIALIZER;
michael@0: 
michael@0: LazyInstance<ThreadLocalBoolean>::Leaky
michael@0:     g_wait_disallowed = LAZY_INSTANCE_INITIALIZER;
michael@0: 
michael@0: }  // anonymous namespace
michael@0: 
michael@0: // static
michael@0: bool ThreadRestrictions::SetIOAllowed(bool allowed) {
michael@0:   bool previous_disallowed = g_io_disallowed.Get().Get();
michael@0:   g_io_disallowed.Get().Set(!allowed);
michael@0:   return !previous_disallowed;
michael@0: }
michael@0: 
michael@0: // static
michael@0: void ThreadRestrictions::AssertIOAllowed() {
michael@0:   if (g_io_disallowed.Get().Get()) {
michael@0:     LOG(FATAL) <<
michael@0:         "Function marked as IO-only was called from a thread that "
michael@0:         "disallows IO!  If this thread really should be allowed to "
michael@0:         "make IO calls, adjust the call to "
michael@0:         "base::ThreadRestrictions::SetIOAllowed() in this thread's "
michael@0:         "startup.";
michael@0:   }
michael@0: }
michael@0: 
michael@0: // static
michael@0: bool ThreadRestrictions::SetSingletonAllowed(bool allowed) {
michael@0:   bool previous_disallowed = g_singleton_disallowed.Get().Get();
michael@0:   g_singleton_disallowed.Get().Set(!allowed);
michael@0:   return !previous_disallowed;
michael@0: }
michael@0: 
michael@0: // static
michael@0: void ThreadRestrictions::AssertSingletonAllowed() {
michael@0:   if (g_singleton_disallowed.Get().Get()) {
michael@0:     LOG(FATAL) << "LazyInstance/Singleton is not allowed to be used on this "
michael@0:                << "thread.  Most likely it's because this thread is not "
michael@0:                << "joinable, so AtExitManager may have deleted the object "
michael@0:                << "on shutdown, leading to a potential shutdown crash.";
michael@0:   }
michael@0: }
michael@0: 
michael@0: // static
michael@0: void ThreadRestrictions::DisallowWaiting() {
michael@0:   g_wait_disallowed.Get().Set(true);
michael@0: }
michael@0: 
michael@0: // static
michael@0: void ThreadRestrictions::AssertWaitAllowed() {
michael@0:   if (g_wait_disallowed.Get().Get()) {
michael@0:     LOG(FATAL) << "Waiting is not allowed to be used on this thread to prevent"
michael@0:                << "jank and deadlock.";
michael@0:   }
michael@0: }
michael@0: 
michael@0: bool ThreadRestrictions::SetWaitAllowed(bool allowed) {
michael@0:   bool previous_disallowed = g_wait_disallowed.Get().Get();
michael@0:   g_wait_disallowed.Get().Set(!allowed);
michael@0:   return !previous_disallowed;
michael@0: }
michael@0: 
michael@0: }  // namespace base
michael@0: 
michael@0: #endif  // ENABLE_THREAD_RESTRICTIONS