| Index: include/private/SkOncePtr.h
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| diff --git a/include/private/SkOncePtr.h b/include/private/SkOncePtr.h
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| deleted file mode 100644
|
| index 921c6a6534b83de2f95a97e836f5d71dba61bc2f..0000000000000000000000000000000000000000
|
| --- a/include/private/SkOncePtr.h
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| +++ /dev/null
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| @@ -1,65 +0,0 @@
|
| -/*
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| - * Copyright 2015 Google Inc.
|
| - *
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| - * Use of this source code is governed by a BSD-style license that can be
|
| - * found in the LICENSE file.
|
| - */
|
| -
|
| -#ifndef SkOncePtr_DEFINED
|
| -#define SkOncePtr_DEFINED
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| -
|
| -#include "../private/SkAtomics.h"
|
| -#include <memory>
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| -
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| -// Use this to create a global static pointer that's intialized exactly once when you call get().
|
| -#define SK_DECLARE_STATIC_ONCE_PTR(type, name) namespace {} static SkBaseOncePtr<type> name;
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| -
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| -template <typename T>
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| -class SkBaseOncePtr {
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| -public:
|
| - template <typename F>
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| - T* get(const F& f) const {
|
| - uintptr_t state = sk_atomic_load(&fState, sk_memory_order_acquire);
|
| - if (state < 2) {
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| - if (state == 0) {
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| - // It looks like no one has tried to create our pointer yet.
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| - // We try to claim that task by atomically swapping our state from '0' to '1'.
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| - // See SkOnce.h for why we use an acquire memory order here rather than relaxed.
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| - if (sk_atomic_compare_exchange(
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| - &fState, &state, (uintptr_t)1, sk_memory_order_acquire, sk_memory_order_acquire)) {
|
| - // We've claimed it. Create our pointer and store it into fState.
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| - state = (uintptr_t)f();
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| - SkASSERT(state > 1);
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| - sk_atomic_store(&fState, state, sk_memory_order_release);
|
| - } else {
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| - // Someone else claimed it.
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| - // We fall through to the spin loop just below to wait for them to finish.
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| - }
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| - }
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| -
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| - while (state == 1) {
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| - // State '1' is our busy-but-not-done state.
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| - // Some other thread has claimed the job of creating our pointer.
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| - // We just need to wait for it to finish.
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| - state = sk_atomic_load(&fState, sk_memory_order_acquire);
|
| - }
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| -
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| - // We shouldn't be able to get here without having created our pointer.
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| - SkASSERT(state > 1);
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| - }
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| - return (T*)state;
|
| - }
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| -
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| - operator T*() const {
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| - auto state = sk_atomic_load(&fState, sk_memory_order_acquire);
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| - return state < 2 ? nullptr : (T*)state;
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| - // TODO: If state == 1 spin until it's not?
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| - }
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| -
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| - // fState == 0 --> we have not created our ptr yet
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| - // fState == 1 --> someone is in the middle of creating our ptr
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| - // else --> (T*)fState is our ptr
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| - mutable uintptr_t fState;
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| -};
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| -
|
| -#endif//SkOncePtr_DEFINED
|
|
|