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Diffstat (limited to 'base/threading/platform_thread.h')
-rw-r--r-- | base/threading/platform_thread.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/base/threading/platform_thread.h b/base/threading/platform_thread.h new file mode 100644 index 0000000..0a3c75d7 --- /dev/null +++ b/base/threading/platform_thread.h @@ -0,0 +1,99 @@ +// Copyright (c) 2010 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/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; + +// A namespace for low-level thread functions. +class PlatformThread { + public: + // Implement this interface to run code on a background thread. Your + // ThreadMain method will be called on the newly created thread. + class 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 a debugger. This has no effect otherwise. + static void SetName(const char* name); + + // 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); + + private: + DISALLOW_IMPLICIT_CONSTRUCTORS(PlatformThread); +}; + +} // namespace base + +#endif // BASE_THREADING_PLATFORM_THREAD_H_ |