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Diffstat (limited to 'Source/cm_auto_ptr.hxx')
-rw-r--r-- | Source/cm_auto_ptr.hxx | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/Source/cm_auto_ptr.hxx b/Source/cm_auto_ptr.hxx new file mode 100644 index 0000000..2cd35c3 --- /dev/null +++ b/Source/cm_auto_ptr.hxx @@ -0,0 +1,221 @@ +/*============================================================================ + CMake - Cross Platform Makefile Generator + Copyright 2000-2016 Kitware, Inc. + + Distributed under the OSI-approved BSD License (the "License"); + see accompanying file Copyright.txt for details. + + This software is distributed WITHOUT ANY WARRANTY; without even the + implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + See the License for more information. +============================================================================*/ +#ifndef CM_AUTO_PTR_HXX +#define CM_AUTO_PTR_HXX + +#include <cmsys/Configure.hxx> + +// FIXME: Use std::auto_ptr on compilers that do not warn about it. +#define CM_AUTO_PTR cm::auto_ptr + +// The HP compiler cannot handle the conversions necessary to use +// auto_ptr_ref to pass an auto_ptr returned from one function +// directly to another function as in use_auto_ptr(get_auto_ptr()). +// We instead use const_cast to achieve the syntax on those platforms. +// We do not use const_cast on other platforms to maintain the C++ +// standard design and guarantee that if an auto_ptr is bound +// to a reference-to-const then ownership will be maintained. +#if defined(__HP_aCC) +#define cm_AUTO_PTR_REF 0 +#define cm_AUTO_PTR_CONST const +#define cm_AUTO_PTR_CAST(a) cast(a) +#else +#define cm_AUTO_PTR_REF 1 +#define cm_AUTO_PTR_CONST +#define cm_AUTO_PTR_CAST(a) a +#endif + +// In C++11, clang will warn about using dynamic exception specifications +// as they are deprecated. But as this class is trying to faithfully +// mimic std::auto_ptr, we want to keep the 'throw()' decorations below. +// So we suppress the warning. +#if defined(__clang__) && defined(__has_warning) +#if __has_warning("-Wdeprecated") +#pragma clang diagnostic push +#pragma clang diagnostic ignored "-Wdeprecated" +#endif +#endif + +namespace cm { + +template <class X> +class auto_ptr; + +#if cm_AUTO_PTR_REF +namespace detail { +// The auto_ptr_ref template is supposed to be a private member of +// auto_ptr but Borland 5.8 cannot handle it. Instead put it in +// a private namespace. +template <class Y> +struct auto_ptr_ref +{ + Y* p_; + + // The extra constructor argument prevents implicit conversion to + // auto_ptr_ref from auto_ptr through the constructor. Normally + // this should be done with the explicit keyword but Borland 5.x + // generates code in the conversion operator to call itself + // infinately. + auto_ptr_ref(Y* p, int) + : p_(p) + { + } +}; +} +#endif + +/** C++98 Standard Section 20.4.5 - Template class auto_ptr. */ +template <class X> +class auto_ptr +{ +#if !cm_AUTO_PTR_REF + template <typename Y> + static inline auto_ptr<Y>& cast(auto_ptr<Y> const& a) + { + return const_cast<auto_ptr<Y>&>(a); + } +#endif + + /** The pointer to the object held. */ + X* x_; + +public: + /** The type of object held by the auto_ptr. */ + typedef X element_type; + + /** Construct from an auto_ptr holding a compatible object. This + transfers ownership to the newly constructed auto_ptr. */ + template <class Y> + auto_ptr(auto_ptr<Y> cm_AUTO_PTR_CONST& a) throw() + : x_(cm_AUTO_PTR_CAST(a).release()) + { + } + + /** Assign from an auto_ptr holding a compatible object. This + transfers ownership to the left-hand-side of the assignment. */ + template <class Y> + auto_ptr& operator=(auto_ptr<Y> cm_AUTO_PTR_CONST& a) throw() + { + this->reset(cm_AUTO_PTR_CAST(a).release()); + return *this; + } + + /** + * Explicitly construct from a raw pointer. This is typically + * called with the result of operator new. For example: + * + * auto_ptr<X> ptr(new X()); + */ + explicit auto_ptr(X* p = 0) throw() + : x_(p) + { + } + + /** Construct from another auto_ptr holding an object of the same + type. This transfers ownership to the newly constructed + auto_ptr. */ + auto_ptr(auto_ptr cm_AUTO_PTR_CONST& a) throw() + : x_(cm_AUTO_PTR_CAST(a).release()) + { + } + + /** Assign from another auto_ptr holding an object of the same type. + This transfers ownership to the newly constructed auto_ptr. */ + auto_ptr& operator=(auto_ptr cm_AUTO_PTR_CONST& a) throw() + { + this->reset(cm_AUTO_PTR_CAST(a).release()); + return *this; + } + + /** Destruct and delete the object held. */ + ~auto_ptr() throw() + { + // Assume object destructor is nothrow. + delete this->x_; + } + + /** Dereference and return a reference to the object held. */ + X& operator*() const throw() { return *this->x_; } + + /** Return a pointer to the object held. */ + X* operator->() const throw() { return this->x_; } + + /** Return a pointer to the object held. */ + X* get() const throw() { return this->x_; } + + /** Return a pointer to the object held and reset to hold no object. + This transfers ownership to the caller. */ + X* release() throw() + { + X* x = this->x_; + this->x_ = 0; + return x; + } + + /** Assume ownership of the given object. The object previously + held is deleted. */ + void reset(X* p = 0) throw() + { + if (this->x_ != p) { + // Assume object destructor is nothrow. + delete this->x_; + this->x_ = p; + } + } + + /** Convert to an auto_ptr holding an object of a compatible type. + This transfers ownership to the returned auto_ptr. */ + template <class Y> + operator auto_ptr<Y>() throw() + { + return auto_ptr<Y>(this->release()); + } + +#if cm_AUTO_PTR_REF + /** Construct from an auto_ptr_ref. This is used when the + constructor argument is a call to a function returning an + auto_ptr. */ + auto_ptr(detail::auto_ptr_ref<X> r) throw() + : x_(r.p_) + { + } + + /** Assign from an auto_ptr_ref. This is used when a function + returning an auto_ptr is passed on the right-hand-side of an + assignment. */ + auto_ptr& operator=(detail::auto_ptr_ref<X> r) throw() + { + this->reset(r.p_); + return *this; + } + + /** Convert to an auto_ptr_ref. This is used when a function + returning an auto_ptr is the argument to the constructor of + another auto_ptr. */ + template <class Y> + operator detail::auto_ptr_ref<Y>() throw() + { + return detail::auto_ptr_ref<Y>(this->release(), 1); + } +#endif +}; + +} // namespace cm + +// Undo warning suppression. +#if defined(__clang__) && defined(__has_warning) +#if __has_warning("-Wdeprecated") +#pragma clang diagnostic pop +#endif +#endif + +#endif |