| Index: src/once.h
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| diff --git a/src/once.h b/src/once.h
|
| deleted file mode 100644
|
| index f319125c052fee7dd9a227057e213a9486b215ef..0000000000000000000000000000000000000000
|
| --- a/src/once.h
|
| +++ /dev/null
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| @@ -1,100 +0,0 @@
|
| -// Copyright 2012 the V8 project authors. All rights reserved.
|
| -// Use of this source code is governed by a BSD-style license that can be
|
| -// found in the LICENSE file.
|
| -
|
| -// emulates google3/base/once.h
|
| -//
|
| -// This header is intended to be included only by v8's internal code. Users
|
| -// should not use this directly.
|
| -//
|
| -// This is basically a portable version of pthread_once().
|
| -//
|
| -// This header declares:
|
| -// * A type called OnceType.
|
| -// * A macro V8_DECLARE_ONCE() which declares a (global) variable of type
|
| -// OnceType.
|
| -// * A function CallOnce(OnceType* once, void (*init_func)()).
|
| -// This function, when invoked multiple times given the same OnceType object,
|
| -// will invoke init_func on the first call only, and will make sure none of
|
| -// the calls return before that first call to init_func has finished.
|
| -//
|
| -// Additionally, the following features are supported:
|
| -// * A macro V8_ONCE_INIT which is expanded into the expression used to
|
| -// initialize a OnceType. This is only useful when clients embed a OnceType
|
| -// into a structure of their own and want to initialize it statically.
|
| -// * The user can provide a parameter which CallOnce() forwards to the
|
| -// user-provided function when it is called. Usage example:
|
| -// CallOnce(&my_once, &MyFunctionExpectingIntArgument, 10);
|
| -// * This implementation guarantees that OnceType is a POD (i.e. no static
|
| -// initializer generated).
|
| -//
|
| -// This implements a way to perform lazy initialization. It's more efficient
|
| -// than using mutexes as no lock is needed if initialization has already
|
| -// happened.
|
| -//
|
| -// Example usage:
|
| -// void Init();
|
| -// V8_DECLARE_ONCE(once_init);
|
| -//
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| -// // Calls Init() exactly once.
|
| -// void InitOnce() {
|
| -// CallOnce(&once_init, &Init);
|
| -// }
|
| -//
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| -// Note that if CallOnce() is called before main() has begun, it must
|
| -// only be called by the thread that will eventually call main() -- that is,
|
| -// the thread that performs dynamic initialization. In general this is a safe
|
| -// assumption since people don't usually construct threads before main() starts,
|
| -// but it is technically not guaranteed. Unfortunately, Win32 provides no way
|
| -// whatsoever to statically-initialize its synchronization primitives, so our
|
| -// only choice is to assume that dynamic initialization is single-threaded.
|
| -
|
| -#ifndef V8_ONCE_H_
|
| -#define V8_ONCE_H_
|
| -
|
| -#include "src/atomicops.h"
|
| -
|
| -namespace v8 {
|
| -namespace internal {
|
| -
|
| -typedef AtomicWord OnceType;
|
| -
|
| -#define V8_ONCE_INIT 0
|
| -
|
| -#define V8_DECLARE_ONCE(NAME) ::v8::internal::OnceType NAME
|
| -
|
| -enum {
|
| - ONCE_STATE_UNINITIALIZED = 0,
|
| - ONCE_STATE_EXECUTING_FUNCTION = 1,
|
| - ONCE_STATE_DONE = 2
|
| -};
|
| -
|
| -typedef void (*NoArgFunction)();
|
| -typedef void (*PointerArgFunction)(void* arg);
|
| -
|
| -template <typename T>
|
| -struct OneArgFunction {
|
| - typedef void (*type)(T);
|
| -};
|
| -
|
| -void CallOnceImpl(OnceType* once, PointerArgFunction init_func, void* arg);
|
| -
|
| -inline void CallOnce(OnceType* once, NoArgFunction init_func) {
|
| - if (Acquire_Load(once) != ONCE_STATE_DONE) {
|
| - CallOnceImpl(once, reinterpret_cast<PointerArgFunction>(init_func), NULL);
|
| - }
|
| -}
|
| -
|
| -
|
| -template <typename Arg>
|
| -inline void CallOnce(OnceType* once,
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| - typename OneArgFunction<Arg*>::type init_func, Arg* arg) {
|
| - if (Acquire_Load(once) != ONCE_STATE_DONE) {
|
| - CallOnceImpl(once, reinterpret_cast<PointerArgFunction>(init_func),
|
| - static_cast<void*>(arg));
|
| - }
|
| -}
|
| -
|
| -} } // namespace v8::internal
|
| -
|
| -#endif // V8_ONCE_H_
|
|
|