1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef SANDBOX_LINUX_SERVICES_THREAD_HELPERS_H_ 6 #define SANDBOX_LINUX_SERVICES_THREAD_HELPERS_H_ 7 8 #include "base/macros.h" 9 #include "sandbox/sandbox_export.h" 10 11 namespace base { class Thread; } 12 13 namespace sandbox { 14 15 class SANDBOX_EXPORT ThreadHelpers { 16 public: 17 // Checks whether the current process is single threaded. |proc_fd| 18 // must be a file descriptor to /proc/ and remains owned by the 19 // caller. 20 static bool IsSingleThreaded(int proc_fd); 21 static bool IsSingleThreaded(); 22 23 // Crashes if the current process is not single threaded. This will wait 24 // on /proc to be updated. In the case where this doesn't crash, this will 25 // return promptly. In the case where this does crash, this will first wait 26 // for a few ms in Debug mode, a few seconds in Release mode. 27 static void AssertSingleThreaded(int proc_fd); 28 static void AssertSingleThreaded(); 29 30 // Starts |thread| and ensure that it has an entry in /proc/self/task/ from 31 // the point of view of the current thread. 32 static bool StartThreadAndWatchProcFS(int proc_fd, base::Thread* thread); 33 34 // Stops |thread| and ensure that it does not have an entry in 35 // /proc/self/task/ from the point of view of the current thread. This is 36 // the way to stop threads before calling IsSingleThreaded(). 37 static bool StopThreadAndWatchProcFS(int proc_fd, base::Thread* thread); 38 39 static const char* GetAssertSingleThreadedErrorMessageForTests(); 40 41 private: 42 DISALLOW_IMPLICIT_CONSTRUCTORS(ThreadHelpers); 43 }; 44 45 } // namespace sandbox 46 47 #endif // SANDBOX_LINUX_SERVICES_THREAD_HELPERS_H_ 48