From de795c6fa9ea4d10431692a673be989a502ac475 Mon Sep 17 00:00:00 2001 From: Mikko Rasa Date: Fri, 8 Oct 2010 19:54:28 +0000 Subject: [PATCH] RefPtr: Add templated copy-ctor and copy-assignment Add assignment from a plain pointer for efficiency Add keep() method to prevent deletion of data Fix a potential leak in cast_dynamic Style updates --- source/core/refptr.h | 81 ++++++++++++++++++++++++++++++++++---------- 1 file changed, 63 insertions(+), 18 deletions(-) diff --git a/source/core/refptr.h b/source/core/refptr.h index dd07256..ddada0b 100644 --- a/source/core/refptr.h +++ b/source/core/refptr.h @@ -1,7 +1,7 @@ /* $Id$ This file is part of libmspcore -Copyright © 2006-2007 Mikko Rasa, Mikkosoft Productions +Copyright © 2006-2007, 2010 Mikko Rasa, Mikkosoft Productions Distributed under the LGPL */ @@ -17,18 +17,35 @@ destroyed, the data is deleted as well. template class RefPtr { +private: + enum + { + KEEP = 1U<<(sizeof(unsigned)*8-1) + }; + public: RefPtr(): data(0), count(0) { } - RefPtr(T *d): data(d), count(0) { if(data) count=new unsigned(1); } + RefPtr(T *d): data(d), count(data ? new unsigned(1) : 0) { } + + // Must have this or the compiler will generate a default copy-c'tor RefPtr(const RefPtr &p): data(p.data), count(p.count) { incref(); } - RefPtr &operator=(const RefPtr &p) + + template + RefPtr(const RefPtr &p): data(p.data), count(p.count) { incref(); } + + RefPtr &operator=(T *d) { decref(); - data=p.data; - count=p.count; - incref(); + data = d; + count = (d ? new unsigned(1) : 0); return *this; } + + // Likewise for the assignment operator + RefPtr &operator=(const RefPtr &p) { return assign(p); } + + template + RefPtr &operator=(const RefPtr &p) { return assign(p); } ~RefPtr() { decref(); } @@ -39,34 +56,56 @@ public: */ T *release() { - T *d=data; - data=0; + T *d = data; + data = 0; decref(); - count=0; + count = 0; return d; } - T *get() const { return data; } - T &operator*() const { return *data; } + /** + Marks the data to not be deleted. This affects all RefPtrs with the same + data. + */ + void keep() + { + if(count) + *count |= KEEP; + } + + T *get() const { return data; } + T &operator*() const { return *data; } T *operator->() const { return data; } operator bool() const { return data!=0; } template - static RefPtr cast_dynamic(const RefPtr &p) { return RefPtr(dynamic_cast(p.data), p.count); } + static RefPtr cast_dynamic(const RefPtr &p) + { return RefPtr(dynamic_cast(p.data), p.count); } + template friend class RefPtr; private: - T *data; + T *data; unsigned *count; - RefPtr(T *d, unsigned *c): data(d), count(c) { incref(); } + RefPtr(T *d, unsigned *c): data(d), count(d ? c : 0) { incref(); } - void incref() + template + RefPtr &assign(const RefPtr &p) + { + decref(); + data = p.data; + count = p.count; + incref(); + return *this; + } + + void incref() { if(!count) return; ++*count; } - void decref() + void decref() { if(!count) return; --*count; @@ -74,8 +113,14 @@ private: { delete data; delete count; - data=0; - count=0; + data = 0; + count = 0; + } + else if(*count==KEEP) + { + delete count; + data = 0; + count = 0; } } }; -- 2.45.2