diff options
Diffstat (limited to 'libodb/odb/tr1/lazy-ptr.hxx')
| -rw-r--r-- | libodb/odb/tr1/lazy-ptr.hxx | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/libodb/odb/tr1/lazy-ptr.hxx b/libodb/odb/tr1/lazy-ptr.hxx new file mode 100644 index 0000000..b4946ec --- /dev/null +++ b/libodb/odb/tr1/lazy-ptr.hxx @@ -0,0 +1,267 @@ +// file : odb/tr1/lazy-ptr.hxx +// license : GNU GPL v2; see accompanying LICENSE file + +#ifndef ODB_TR1_LAZY_PTR_HXX +#define ODB_TR1_LAZY_PTR_HXX + +#include <odb/pre.hxx> + +// +// This header assumes that the necessary TR1 header has already +// been included. +// + +#include <memory> // std::auto_ptr + +#include <odb/forward.hxx> // odb::database +#include <odb/traits.hxx> +#include <odb/lazy-ptr-impl.hxx> +#include <odb/details/config.hxx> // ODB_CXX11 + +namespace odb +{ + namespace tr1 + { + template <class T> + class lazy_weak_ptr; + + // + // + template <class T> + class lazy_shared_ptr + { + // The standard shared_ptr interface. + // + public: + typedef T element_type; + + lazy_shared_ptr (); + template <class Y> explicit lazy_shared_ptr (Y*); + template <class Y, class D> lazy_shared_ptr (Y*, D); + + lazy_shared_ptr (const lazy_shared_ptr&); + template <class Y> lazy_shared_ptr (const lazy_shared_ptr<Y>&); + template <class Y> explicit lazy_shared_ptr (const lazy_weak_ptr<Y>&); + template <class Y> explicit lazy_shared_ptr (std::auto_ptr<Y>&); + + ~lazy_shared_ptr (); + + lazy_shared_ptr& operator= (const lazy_shared_ptr&); + template <class Y> lazy_shared_ptr& operator= (const lazy_shared_ptr<Y>&); + template <class Y> lazy_shared_ptr& operator= (std::auto_ptr<Y>&); + + void swap (lazy_shared_ptr&); + void reset (); + template <class Y> void reset (Y*); + template <class Y, class D> void reset (Y*, D); + + T& operator* () const; + T* operator-> () const; + T* get () const; + + bool unique () const; + long use_count () const; + + typedef std::tr1::shared_ptr<T> lazy_shared_ptr::*unspecified_bool_type; + operator unspecified_bool_type () const + { + return (p_ || i_) ? &lazy_shared_ptr::p_ : 0; + } + + // Initialization/assignment from shared_ptr and weak_ptr. + // + public: + template <class Y> lazy_shared_ptr (const std::tr1::shared_ptr<Y>&); + template <class Y> explicit lazy_shared_ptr (const std::tr1::weak_ptr<Y>&); + + template <class Y> lazy_shared_ptr& operator= (const std::tr1::shared_ptr<Y>&); + + // Lazy loading interface. + // + public: + typedef odb::database database_type; + + // NULL loaded() + // + // true true NULL pointer to transient object + // false true valid pointer to persistent object + // true false unloaded pointer to persistent object + // false false valid pointer to transient object + // + bool loaded () const; + + std::tr1::shared_ptr<T> load () const; + + // Unload the pointer. For transient objects this function is + // equivalent to reset(). + // + void unload () const; + + // Get the underlying eager pointer. If this is an unloaded pointer + // to a persistent object, then the returned pointer will be NULL. + // + std::tr1::shared_ptr<T> get_eager () const; + + template <class DB, class ID> lazy_shared_ptr (DB&, const ID&); + template <class DB, class Y> lazy_shared_ptr (DB&, Y*); + template <class DB, class Y, class D> lazy_shared_ptr (DB&, Y*, D); + template <class DB, class Y> lazy_shared_ptr (DB&, std::auto_ptr<Y>&); + template <class DB, class Y> lazy_shared_ptr (DB&, const std::tr1::shared_ptr<Y>&); + template <class DB, class Y> lazy_shared_ptr (DB&, const std::tr1::weak_ptr<Y>&); + + template <class DB, class ID> void reset (DB&, const ID&); + template <class DB, class Y> void reset (DB&, Y*); + template <class DB, class Y, class D> void reset (DB&, Y*, D); + template <class DB, class Y> void reset (DB&, std::auto_ptr<Y>&); + template <class DB, class Y> void reset (DB&, const std::tr1::shared_ptr<Y>&); + +#ifdef ODB_CXX11_FUNCTION_TEMPLATE_DEFAULT_ARGUMENT + template <class O = T> +#else + template <class O /*= T*/> +#endif + typename object_traits<O>::id_type object_id () const; + + database_type& database () const; + + // Helpers. + // + public: + template <class Y> bool equal (const lazy_shared_ptr<Y>&) const; + + private: + template <class Y> friend class lazy_shared_ptr; + template <class Y> friend class lazy_weak_ptr; + + // For lazy_weak_ptr::lock(). + // + lazy_shared_ptr (const std::tr1::shared_ptr<T>& p, + const lazy_ptr_impl<T>& i) + : p_ (p), i_ (i) {} + + private: + mutable std::tr1::shared_ptr<T> p_; + mutable lazy_ptr_impl<T> i_; + }; + + // operator< and operator<< are not provided. + // + template<class T, class Y> + bool operator== (const lazy_shared_ptr<T>&, const lazy_shared_ptr<Y>&); + + template<class T, class Y> + bool operator!= (const lazy_shared_ptr<T>&, const lazy_shared_ptr<Y>&); + + template<class T> void swap (lazy_shared_ptr<T>&, lazy_shared_ptr<T>&); + + template<class D, class T> + D* get_deleter (const lazy_shared_ptr<T>&); + + // + // + template <class T> + class lazy_weak_ptr + { + // The standard weak_ptr interface. + // + public: + typedef T element_type; + + lazy_weak_ptr (); + template <class Y> lazy_weak_ptr (const lazy_shared_ptr<Y>&); + lazy_weak_ptr (const lazy_weak_ptr&); + template <class Y> lazy_weak_ptr (const lazy_weak_ptr<Y>&); + + ~lazy_weak_ptr (); + + lazy_weak_ptr& operator= (const lazy_weak_ptr&); + template <class Y> lazy_weak_ptr& operator= (const lazy_weak_ptr<Y>&); + template <class Y> lazy_weak_ptr& operator= (const lazy_shared_ptr<Y>&); + + void swap (lazy_weak_ptr<T>&); + void reset (); + + long use_count () const; + bool expired () const; + + lazy_shared_ptr<T> lock () const; + + // Initialization/assignment from shared_ptr and weak_ptr. + // + public: + template <class Y> lazy_weak_ptr (const std::tr1::weak_ptr<Y>&); + template <class Y> lazy_weak_ptr (const std::tr1::shared_ptr<Y>&); + + template <class Y> lazy_weak_ptr& operator= (const std::tr1::weak_ptr<Y>&); + template <class Y> lazy_weak_ptr& operator= (const std::tr1::shared_ptr<Y>&); + + // Lazy loading interface. + // + public: + typedef odb::database database_type; + + // expired() loaded() + // + // true true expired pointer to transient object + // false true valid pointer to persistent object + // true false expired pointer to persistent object + // false false valid pointer to transient object + // + bool loaded () const; + + // Performs both lock and load. + // + std::tr1::shared_ptr<T> load () const; + + // Unload the pointer. For transient objects this function is + // equivalent to reset(). + // + void unload () const; + + // Get the underlying eager pointer. If this is an unloaded pointer + // to a persistent object, then the returned pointer will be NULL. + // + std::tr1::weak_ptr<T> get_eager () const; + + template <class DB, class ID> lazy_weak_ptr (DB&, const ID&); + template <class DB, class Y> lazy_weak_ptr (DB&, const std::tr1::shared_ptr<Y>&); + template <class DB, class Y> lazy_weak_ptr (DB&, const std::tr1::weak_ptr<Y>&); + + template <class DB, class ID> void reset (DB&, const ID&); + template <class DB, class Y> void reset (DB&, const std::tr1::shared_ptr<Y>&); + template <class DB, class Y> void reset (DB&, const std::tr1::weak_ptr<Y>&); + + // The object_id() function can only be called when the object is + // persistent, or: expired() XOR loaded() (can use != for XOR). + // +#ifdef ODB_CXX11_FUNCTION_TEMPLATE_DEFAULT_ARGUMENT + template <class O = T> +#else + template <class O /* = T */> +#endif + typename object_traits<O>::id_type object_id () const; + + database_type& database () const; + + private: + template <class Y> friend class lazy_shared_ptr; + template <class Y> friend class lazy_weak_ptr; + + mutable std::tr1::weak_ptr<T> p_; + mutable lazy_ptr_impl<T> i_; + }; + + // operator< is not provided. + // + template<class T> void swap (lazy_weak_ptr<T>&, lazy_weak_ptr<T>&); + } +} + +#include <odb/tr1/lazy-ptr.ixx> +#include <odb/tr1/lazy-ptr.txx> + +#include <odb/tr1/lazy-pointer-traits.hxx> + +#include <odb/post.hxx> + +#endif // ODB_TR1_LAZY_PTR_HXX |