| Index: include/core/SkWeakRefCnt.h
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| diff --git a/include/core/SkWeakRefCnt.h b/include/core/SkWeakRefCnt.h
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| deleted file mode 100644
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| index a550951970c925eb93d86bb6aa9869c52fa054ca..0000000000000000000000000000000000000000
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| --- a/include/core/SkWeakRefCnt.h
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| +++ /dev/null
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| @@ -1,159 +0,0 @@
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| -/*
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| - * Copyright 2012 Google Inc.
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| - *
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| - * Use of this source code is governed by a BSD-style license that can be
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| - * found in the LICENSE file.
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| - */
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| -
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| -#ifndef SkWeakRefCnt_DEFINED
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| -#define SkWeakRefCnt_DEFINED
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| -
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| -#include "SkRefCnt.h"
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| -#include "SkAtomics.h"
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| -
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| -/** \class SkWeakRefCnt
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| -
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| -    SkWeakRefCnt is the base class for objects that may be shared by multiple
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| -    objects. When an existing strong owner wants to share a reference, it calls
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| -    ref(). When a strong owner wants to release its reference, it calls
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| -    unref(). When the shared object's strong reference count goes to zero as
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| -    the result of an unref() call, its (virtual) weak_dispose method is called.
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| -    It is an error for the destructor to be called explicitly (or via the
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| -    object going out of scope on the stack or calling delete) if
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| -    getRefCnt() > 1.
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| -
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| -    In addition to strong ownership, an owner may instead obtain a weak
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| -    reference by calling weak_ref(). A call to weak_ref() must be balanced by a
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| -    call to weak_unref(). To obtain a strong reference from a weak reference,
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| -    call try_ref(). If try_ref() returns true, the owner's pointer is now also
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| -    a strong reference on which unref() must be called. Note that this does not
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| -    affect the original weak reference, weak_unref() must still be called. When
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| -    the weak reference count goes to zero, the object is deleted. While the
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| -    weak reference count is positive and the strong reference count is zero the
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| -    object still exists, but will be in the disposed state. It is up to the
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| -    object to define what this means.
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| -
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| -    Note that a strong reference implicitly implies a weak reference. As a
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| -    result, it is allowable for the owner of a strong ref to call try_ref().
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| -    This will have the same effect as calling ref(), but may be more expensive.
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| -
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| -    Example:
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| -
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| -    SkWeakRefCnt myRef = strongRef.weak_ref();
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| -    ... // strongRef.unref() may or may not be called
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| -    if (myRef.try_ref()) {
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| -        ... // use myRef
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| -        myRef.unref();
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| -    } else {
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| -        // myRef is in the disposed state
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| -    }
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| -    myRef.weak_unref();
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| -*/
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| -class SK_API SkWeakRefCnt : public SkRefCnt {
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| -public:
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| -    /** Default construct, initializing the reference counts to 1.
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| -        The strong references collectively hold one weak reference. When the
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| -        strong reference count goes to zero, the collectively held weak
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| -        reference is released.
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| -    */
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| -    SkWeakRefCnt() : SkRefCnt(), fWeakCnt(1) {}
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| -
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| -    /** Destruct, asserting that the weak reference count is 1.
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| -    */
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| -    virtual ~SkWeakRefCnt() {
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| -#ifdef SK_DEBUG
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| -        SkASSERT(fWeakCnt == 1);
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| -        fWeakCnt = 0;
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| -#endif
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| -    }
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| -
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| -    /** Return the weak reference count.
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| -    */
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| -    int32_t getWeakCnt() const { return fWeakCnt; }
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| -
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| -#ifdef SK_DEBUG
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| -    void validate() const {
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| -        this->INHERITED::validate();
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| -        SkASSERT(fWeakCnt > 0);
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| -    }
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| -#endif
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| -
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| -    /** Creates a strong reference from a weak reference, if possible. The
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| -        caller must already be an owner. If try_ref() returns true the owner
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| -        is in posession of an additional strong reference. Both the original
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| -        reference and new reference must be properly unreferenced. If try_ref()
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| -        returns false, no strong reference could be created and the owner's
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| -        reference is in the same state as before the call.
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| -    */
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| -    bool SK_WARN_UNUSED_RESULT try_ref() const {
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| -        if (sk_atomic_conditional_inc(&fRefCnt) != 0) {
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| -            // Acquire barrier (L/SL), if not provided above.
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| -            // Prevents subsequent code from happening before the increment.
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| -            sk_membar_acquire__after_atomic_conditional_inc();
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| -            return true;
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| -        }
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| -        return false;
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| -    }
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| -
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| -    /** Increment the weak reference count. Must be balanced by a call to
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| -        weak_unref().
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| -    */
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| -    void weak_ref() const {
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| -        SkASSERT(fRefCnt > 0);
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| -        SkASSERT(fWeakCnt > 0);
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| -        sk_atomic_inc(&fWeakCnt);  // No barrier required.
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| -    }
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| -
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| -    /** Decrement the weak reference count. If the weak reference count is 1
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| -        before the decrement, then call delete on the object. Note that if this
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| -        is the case, then the object needs to have been allocated via new, and
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| -        not on the stack.
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| -    */
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| -    void weak_unref() const {
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| -        SkASSERT(fWeakCnt > 0);
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| -        // Release barrier (SL/S), if not provided below.
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| -        if (sk_atomic_dec(&fWeakCnt) == 1) {
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| -            // Acquire barrier (L/SL), if not provided above.
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| -            // Prevents code in destructor from happening before the decrement.
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| -            sk_membar_acquire__after_atomic_dec();
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| -#ifdef SK_DEBUG
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| -            // so our destructor won't complain
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| -            fWeakCnt = 1;
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| -#endif
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| -            this->INHERITED::internal_dispose();
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| -        }
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| -    }
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| -
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| -    /** Returns true if there are no strong references to the object. When this
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| -        is the case all future calls to try_ref() will return false.
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| -    */
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| -    bool weak_expired() const {
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| -        return fRefCnt == 0;
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| -    }
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| -
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| -protected:
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| -    /** Called when the strong reference count goes to zero. This allows the
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| -        object to free any resources it may be holding. Weak references may
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| -        still exist and their level of allowed access to the object is defined
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| -        by the object's class.
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| -    */
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| -    virtual void weak_dispose() const {
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| -    }
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| -
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| -private:
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| -    /** Called when the strong reference count goes to zero. Calls weak_dispose
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| -        on the object and releases the implicit weak reference held
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| -        collectively by the strong references.
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| -    */
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| -    void internal_dispose() const override {
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| -        weak_dispose();
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| -        weak_unref();
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| -    }
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| -
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| -    /* Invariant: fWeakCnt = #weak + (fRefCnt > 0 ? 1 : 0) */
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| -    mutable int32_t fWeakCnt;
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| -
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| -    typedef SkRefCnt INHERITED;
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| -};
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| -
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| -#endif
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| 
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