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Commit 8c3c51bb authored by Mathias Agopian's avatar Mathias Agopian
Browse files

Fix a bug in sp<> and wp<> which could cause memory corruptions 

when assigning a smart pointer to another one, we need to make
sure to read all the data we need from the right-hand-side
reference (the assignee) before we decRef the assigned.

This bug would cause linked-list of smart-pointers to fail
miserably.

Change-Id: Ibb554c15fddf909f7737c632b7c80322e80ea93f
parent 01e4483b

include/utils/RefBase.h

+20 −12
Original line number Diff line number Diff line
@@ -333,9 +333,10 @@ sp<T>::~sp() 


template<typename T>

sp<T>& sp<T>::operator = (const sp<T>& other) {

    if (other.m_ptr) other.m_ptr->incStrong(this);

    T* otherPtr(other.m_ptr);

    if (otherPtr) otherPtr->incStrong(this);

    if (m_ptr) m_ptr->decStrong(this);

    m_ptr = other.m_ptr;

    m_ptr = otherPtr;

    return *this;

}
@@ -351,9 +352,10 @@ sp<T>& sp<T>::operator = (T* other) 
template<typename T> template<typename U>

sp<T>& sp<T>::operator = (const sp<U>& other)

{

    if (other.m_ptr) other.m_ptr->incStrong(this);

    U* otherPtr(other.m_ptr);

    if (otherPtr) otherPtr->incStrong(this);

    if (m_ptr) m_ptr->decStrong(this);

    m_ptr = other.m_ptr;

    m_ptr = otherPtr;

    return *this;

}
@@ -466,10 +468,12 @@ wp<T>& wp<T>::operator = (T* other) 
template<typename T>

wp<T>& wp<T>::operator = (const wp<T>& other)

{

    if (other.m_ptr) other.m_refs->incWeak(this);

    weakref_type* otherRefs(other.m_refs);

    T* otherPtr(other.m_ptr);

    if (otherPtr) otherRefs->incWeak(this);

    if (m_ptr) m_refs->decWeak(this);

    m_ptr = other.m_ptr;

    m_refs = other.m_refs;

    m_ptr = otherPtr;

    m_refs = otherRefs;

    return *this;

}
@@ -478,8 +482,9 @@ wp<T>& wp<T>::operator = (const sp<T>& other) 
{

    weakref_type* newRefs =

        other != NULL ? other->createWeak(this) : 0;

    T* otherPtr(other.m_ptr);

    if (m_ptr) m_refs->decWeak(this);

    m_ptr = other.get();

    m_ptr = otherPtr;

    m_refs = newRefs;

    return *this;

}
@@ -498,10 +503,12 @@ wp<T>& wp<T>::operator = (U* other) 
template<typename T> template<typename U>

wp<T>& wp<T>::operator = (const wp<U>& other)

{

    if (other.m_ptr) other.m_refs->incWeak(this);

    weakref_type* otherRefs(other.m_refs);

    U* otherPtr(other.m_ptr);

    if (otherPtr) otherRefs->incWeak(this);

    if (m_ptr) m_refs->decWeak(this);

    m_ptr = other.m_ptr;

    m_refs = other.m_refs;

    m_ptr = otherPtr;

    m_refs = otherRefs;

    return *this;

}
@@ -510,8 +517,9 @@ wp<T>& wp<T>::operator = (const sp<U>& other) 
{

    weakref_type* newRefs =

        other != NULL ? other->createWeak(this) : 0;

    U* otherPtr(other.m_ptr);

    if (m_ptr) m_refs->decWeak(this);

    m_ptr = other.get();

    m_ptr = otherPtr;

    m_refs = newRefs;

    return *this;

}