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+// Copyright (c) 2011 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.
+
+// WARNING: You should *NOT* be using this class directly. PlatformThread is
+// the low-level platform-specific abstraction to the OS's threading interface.
+// You should instead be using a message-loop driven Thread, see thread.h.
+
+#ifndef BASE_THREADING_PLATFORM_THREAD_H_
+#define BASE_THREADING_PLATFORM_THREAD_H_
+#pragma once
+
+#include "base/base_export.h"
+#include "base/basictypes.h"
+#include "build/build_config.h"
+
+#if defined(OS_WIN)
+#include <windows.h>
+#elif defined(OS_POSIX)
+#include <pthread.h>
+#if defined(OS_MACOSX)
+#include <mach/mach.h>
+#else // OS_POSIX && !OS_MACOSX
+#include <unistd.h>
+#endif
+#endif
+
+namespace base {
+
+// PlatformThreadHandle should not be assumed to be a numeric type, since the
+// standard intends to allow pthread_t to be a structure. This means you
+// should not initialize it to a value, like 0. If it's a member variable, the
+// constructor can safely "value initialize" using () in the initializer list.
+#if defined(OS_WIN)
+typedef DWORD PlatformThreadId;
+typedef void* PlatformThreadHandle; // HANDLE
+const PlatformThreadHandle kNullThreadHandle = NULL;
+#elif defined(OS_POSIX)
+typedef pthread_t PlatformThreadHandle;
+const PlatformThreadHandle kNullThreadHandle = 0;
+#if defined(OS_MACOSX)
+typedef mach_port_t PlatformThreadId;
+#else // OS_POSIX && !OS_MACOSX
+typedef pid_t PlatformThreadId;
+#endif
+#endif
+
+const PlatformThreadId kInvalidThreadId = 0;
+
+// Valid values for SetThreadPriority()
+enum ThreadPriority{
+ kThreadPriority_Normal,
+ // Suitable for low-latency, glitch-resistant audio.
+ kThreadPriority_RealtimeAudio
+};
+
+// A namespace for low-level thread functions.
+class BASE_EXPORT PlatformThread {
+ public:
+ // Implement this interface to run code on a background thread. Your
+ // ThreadMain method will be called on the newly created thread.
+ class BASE_EXPORT Delegate {
+ public:
+ virtual ~Delegate() {}
+ virtual void ThreadMain() = 0;
+ };
+
+ // Gets the current thread id, which may be useful for logging purposes.
+ static PlatformThreadId CurrentId();
+
+ // Yield the current thread so another thread can be scheduled.
+ static void YieldCurrentThread();
+
+ // Sleeps for the specified duration (units are milliseconds).
+ static void Sleep(int duration_ms);
+
+ // Sets the thread name visible to debuggers/tools. This has no effect
+ // otherwise. This name pointer is not copied internally. Thus, it must stay
+ // valid until the thread ends.
+ static void SetName(const char* name);
+
+ // Gets the thread name, if previously set by SetName.
+ static const char* GetName();
+
+ // Creates a new thread. The |stack_size| parameter can be 0 to indicate
+ // that the default stack size should be used. Upon success,
+ // |*thread_handle| will be assigned a handle to the newly created thread,
+ // and |delegate|'s ThreadMain method will be executed on the newly created
+ // thread.
+ // NOTE: When you are done with the thread handle, you must call Join to
+ // release system resources associated with the thread. You must ensure that
+ // the Delegate object outlives the thread.
+ static bool Create(size_t stack_size, Delegate* delegate,
+ PlatformThreadHandle* thread_handle);
+
+ // CreateNonJoinable() does the same thing as Create() except the thread
+ // cannot be Join()'d. Therefore, it also does not output a
+ // PlatformThreadHandle.
+ static bool CreateNonJoinable(size_t stack_size, Delegate* delegate);
+
+ // Joins with a thread created via the Create function. This function blocks
+ // the caller until the designated thread exits. This will invalidate
+ // |thread_handle|.
+ static void Join(PlatformThreadHandle thread_handle);
+
+ static void SetThreadPriority(PlatformThreadHandle handle,
+ ThreadPriority priority);
+
+ private:
+ DISALLOW_IMPLICIT_CONSTRUCTORS(PlatformThread);
+};
+
+} // namespace base
+
+#endif // BASE_THREADING_PLATFORM_THREAD_H_