The Tor Browser: security/sandbox/chromium/base/threading/platform_thread

security/sandbox/chromium/base/threading/platform_thread_win.cc@925c144e1f1f (annotated)

security/sandbox/chromium/base/threading/platform_thread_win.cc

Fri, 16 Jan 2015 18:13:44 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Fri, 16 Jan 2015 18:13:44 +0100
branch: TOR_BUG_9701
changeset 14: 925c144e1f1f
permissions: -rw-r--r--

Integrate suggestion from review to improve consistency with existing code.

 // 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/platform_thread.h"
 #include "base/debug/alias.h"
 #include "base/debug/profiler.h"
 #include "base/logging.h"
 #include "base/threading/thread_id_name_manager.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/tracked_objects.h"
 #include "base/win/windows_version.h"
 namespace base {
 namespace {
 // The information on how to set the thread name comes from
 // a MSDN article: http://msdn2.microsoft.com/en-us/library/xcb2z8hs.aspx
 const DWORD kVCThreadNameException = 0x406D1388;
 typedef struct tagTHREADNAME_INFO {
   DWORD dwType;  // Must be 0x1000.
   LPCSTR szName;  // Pointer to name (in user addr space).
   DWORD dwThreadID;  // Thread ID (-1=caller thread).
   DWORD dwFlags;  // Reserved for future use, must be zero.
 } THREADNAME_INFO;
 // This function has try handling, so it is separated out of its caller.
 void SetNameInternal(PlatformThreadId thread_id, const char* name) {
   THREADNAME_INFO info;
   info.dwType = 0x1000;
   info.szName = name;
   info.dwThreadID = thread_id;
   info.dwFlags = 0;
   __try {
     RaiseException(kVCThreadNameException, 0, sizeof(info)/sizeof(DWORD),
                    reinterpret_cast<DWORD_PTR*>(&info));
   } __except(EXCEPTION_CONTINUE_EXECUTION) {
   }
 }
 struct ThreadParams {
   PlatformThread::Delegate* delegate;
   bool joinable;
 };
 DWORD __stdcall ThreadFunc(void* params) {
   ThreadParams* thread_params = static_cast<ThreadParams*>(params);
   PlatformThread::Delegate* delegate = thread_params->delegate;
   if (!thread_params->joinable)
     base::ThreadRestrictions::SetSingletonAllowed(false);
   /* Retrieve a copy of the thread handle to use as the key in the
    * thread name mapping. */
   PlatformThreadHandle::Handle platform_handle;
   DuplicateHandle(
       GetCurrentProcess(),
       GetCurrentThread(),
       GetCurrentProcess(),
       &platform_handle,
 ,
       FALSE,
       DUPLICATE_SAME_ACCESS);
   ThreadIdNameManager::GetInstance()->RegisterThread(
       platform_handle,
       PlatformThread::CurrentId());
   delete thread_params;
   delegate->ThreadMain();
   ThreadIdNameManager::GetInstance()->RemoveName(
       platform_handle,
       PlatformThread::CurrentId());
   return NULL;
 }
 // CreateThreadInternal() matches PlatformThread::Create(), except that
 // |out_thread_handle| may be NULL, in which case a non-joinable thread is
 // created.
 bool CreateThreadInternal(size_t stack_size,
                           PlatformThread::Delegate* delegate,
                           PlatformThreadHandle* out_thread_handle) {
   unsigned int flags = 0;
   if (stack_size > 0 && base::win::GetVersion() >= base::win::VERSION_XP) {
     flags = STACK_SIZE_PARAM_IS_A_RESERVATION;
   } else {
     stack_size = 0;
   }
   ThreadParams* params = new ThreadParams;
   params->delegate = delegate;
   params->joinable = out_thread_handle != NULL;
   // Using CreateThread here vs _beginthreadex makes thread creation a bit
   // faster and doesn't require the loader lock to be available.  Our code will
   // have to work running on CreateThread() threads anyway, since we run code
   // on the Windows thread pool, etc.  For some background on the difference:
   //   http://www.microsoft.com/msj/1099/win32/win321099.aspx
   void* thread_handle = CreateThread(
       NULL, stack_size, ThreadFunc, params, flags, NULL);
   if (!thread_handle) {
     delete params;
     return false;
   }
   if (out_thread_handle)
     *out_thread_handle = PlatformThreadHandle(thread_handle);
   else
     CloseHandle(thread_handle);
   return true;
 }
 }  // namespace
 // static
 PlatformThreadId PlatformThread::CurrentId() {
   return GetCurrentThreadId();
 }
 // static
 PlatformThreadHandle PlatformThread::CurrentHandle() {
   NOTIMPLEMENTED(); // See OpenThread()
   return PlatformThreadHandle();
 }
 // static
 void PlatformThread::YieldCurrentThread() {
   ::Sleep(0);
 }
 // static
 void PlatformThread::Sleep(TimeDelta duration) {
   // When measured with a high resolution clock, Sleep() sometimes returns much
   // too early. We may need to call it repeatedly to get the desired duration.
   TimeTicks end = TimeTicks::Now() + duration;
   TimeTicks now;
   while ((now = TimeTicks::Now()) < end)
     ::Sleep((end - now).InMillisecondsRoundedUp());
 }
 // static
 void PlatformThread::SetName(const char* name) {
   ThreadIdNameManager::GetInstance()->SetName(CurrentId(), name);
   // On Windows only, we don't need to tell the profiler about the "BrokerEvent"
   // thread, as it exists only in the chrome.exe image, and never spawns or runs
   // tasks (items which could be profiled).  This test avoids the notification,
   // which would also (as a side effect) initialize the profiler in this unused
   // context, including setting up thread local storage, etc.  The performance
   // impact is not terrible, but there is no reason to do initialize it.
   if (0 != strcmp(name, "BrokerEvent"))
     tracked_objects::ThreadData::InitializeThreadContext(name);
   // The debugger needs to be around to catch the name in the exception.  If
   // there isn't a debugger, we are just needlessly throwing an exception.
   // If this image file is instrumented, we raise the exception anyway
   // to provide the profiler with human-readable thread names.
   if (!::IsDebuggerPresent() && !base::debug::IsBinaryInstrumented())
     return;
   SetNameInternal(CurrentId(), name);
 }
 // static
 const char* PlatformThread::GetName() {
   return ThreadIdNameManager::GetInstance()->GetName(CurrentId());
 }
 // static
 bool PlatformThread::Create(size_t stack_size, Delegate* delegate,
                             PlatformThreadHandle* thread_handle) {
   DCHECK(thread_handle);
   return CreateThreadInternal(stack_size, delegate, thread_handle);
 }
 // static
 bool PlatformThread::CreateWithPriority(size_t stack_size, Delegate* delegate,
                                         PlatformThreadHandle* thread_handle,
                                         ThreadPriority priority) {
   bool result = Create(stack_size, delegate, thread_handle);
   if (result)
     SetThreadPriority(*thread_handle, priority);
   return result;
 }
 // static
 bool PlatformThread::CreateNonJoinable(size_t stack_size, Delegate* delegate) {
   return CreateThreadInternal(stack_size, delegate, NULL);
 }
 // static
 void PlatformThread::Join(PlatformThreadHandle thread_handle) {
   DCHECK(thread_handle.handle_);
   // TODO(willchan): Enable this check once I can get it to work for Windows
   // shutdown.
   // Joining another thread may block the current thread for a long time, since
   // the thread referred to by |thread_handle| may still be running long-lived /
   // blocking tasks.
 #if 0
   base::ThreadRestrictions::AssertIOAllowed();
 #endif
   // Wait for the thread to exit.  It should already have terminated but make
   // sure this assumption is valid.
   DWORD result = WaitForSingleObject(thread_handle.handle_, INFINITE);
   if (result != WAIT_OBJECT_0) {
     // Debug info for bug 127931.
     DWORD error = GetLastError();
     debug::Alias(&error);
     debug::Alias(&result);
     debug::Alias(&thread_handle.handle_);
     CHECK(false);
   }
   CloseHandle(thread_handle.handle_);
 }
 // static
 void PlatformThread::SetThreadPriority(PlatformThreadHandle handle,
                                        ThreadPriority priority) {
   switch (priority) {
     case kThreadPriority_Normal:
       ::SetThreadPriority(handle.handle_, THREAD_PRIORITY_NORMAL);
       break;
     case kThreadPriority_RealtimeAudio:
       ::SetThreadPriority(handle.handle_, THREAD_PRIORITY_TIME_CRITICAL);
       break;
     default:
       NOTREACHED() << "Unknown priority.";
       break;
   }
 }
 }  // namespace base

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security/sandbox/chromium/base/threading/platform_thread_win.cc@925c144e1f1f (annotated)

security/sandbox/chromium/base/threading/platform_thread_win.cc