#include <bslma_allocatorutil.h>

Detailed Description

Namespace for utility functions on allocators

Static Public Member Functions
template<class t_ALLOC >
static bsl::enable_if<!IsDerivedFromBslAllocator< t_ALLOC >::value, t_ALLOC >::type	adapt (const t_ALLOC &from)

template<class t_TYPE >
static bslma::Allocator *	adapt (const bsl::allocator< t_TYPE > &from)

template<class t_ALLOCATOR >
static AllocatorUtil_Traits< t_ALLOCATOR >::void_pointer	allocateBytes (const t_ALLOCATOR &allocator, std::size_t nbytes, std::size_t alignment=0)

template<class t_TYPE , class t_ALLOCATOR >
static AllocatorUtil_Traits< t_ALLOCATOR, t_TYPE >::pointer	allocateObject (const t_ALLOCATOR &allocator, std::size_t n=1)

template<class t_TYPE >
static t_TYPE &	assign (t_TYPE *lhs, const t_TYPE &rhs, bsl::true_type allowed)

template<class t_TYPE >
static t_TYPE &	assign (t_TYPE *lhs, const t_TYPE &rhs, bsl::false_type allowed)

template<class t_ALLOCATOR >
static void	deallocateBytes (const t_ALLOCATOR &allocator, typename AllocatorUtil_Traits< t_ALLOCATOR >::void_pointer p, std::size_t nbytes, std::size_t alignment=0)

template<class t_ALLOCATOR , class t_POINTER >
static void	deallocateObject (const t_ALLOCATOR &allocator, t_POINTER p, std::size_t n=1)

template<class t_ALLOCATOR , class t_POINTER >
static void	deleteObject (const t_ALLOCATOR &allocator, t_POINTER p)

template<class t_TYPE , class t_ALLOCATOR >
static AllocatorUtil_Traits< t_ALLOCATOR, t_TYPE >::pointer	newObject (const t_ALLOCATOR &allocator)

template<class t_TYPE , class t_ALLOCATOR , class t_ARG1 , class... t_ARGS>
static AllocatorUtil_Traits< t_ALLOCATOR, t_TYPE >::pointer	newObject (const t_ALLOCATOR &allocator, t_ARG1 &argument1, t_ARGS &&... arguments)

template<class t_TYPE , class t_ALLOCATOR , class t_ARG1 , class... t_ARGS>
static AllocatorUtil_Traits< t_ALLOCATOR, t_TYPE >::pointer	newObject (const t_ALLOCATOR &allocator, BSLS_COMPILERFEATURES_FORWARD_REF(t_ARG1) argument1, t_ARGS &&... arguments)

template<class t_TYPE >
static void	swap (t_TYPE pa, t_TYPE pb, bsl::false_type allowed)

template<class t_TYPE >
static void	swap (t_TYPE pa, t_TYPE pb, bsl::true_type allowed)

Member Function Documentation

◆ adapt() [1/2]

template<class t_TYPE >

bslma::Allocator * bslma::AllocatorUtil::adapt ( const bsl::allocator< t_TYPE > & from )

inlinestatic

◆ adapt() [2/2]

template<class t_ALLOC >

bsl::enable_if<!AllocatorUtil::IsDerivedFromBslAllocator< t_ALLOC >::value, t_ALLOC >::type bslma::AllocatorUtil::adapt ( const t_ALLOC & from )

inlinestatic

Return the specified from allocator adapted to a type most likely to be usable for initializing another AA object. Specifically, return from.mechanism() if from is a specialization of bsl::allocator (or a class derived from bsl::allocator); otherwise return from unchanged.

◆ allocateBytes()

template<class t_ALLOCATOR >

AllocatorUtil_Traits< t_ALLOCATOR >::void_pointer bslma::AllocatorUtil::allocateBytes	(	const t_ALLOCATOR &	allocator,
		std::size_t	nbytes,
		std::size_t	alignment = `0`
	)

inlinestatic

Return a pointer to a block of raw memory allocated from the specified allocator having the specified nbytes size and optionally specified alignment. If alignment is not specified, the natural alignment for an object of size nbytes is used. If alignment is larger than the largest supported alignment for t_ALLOCATOR, either the block will be aligned to the maximum supported alignment or an exception will be thrown; the specific choice of behavior is determined by the allocator. For polymorphic allocators the behavior of extended alignment is determined by the memory resource, whereas for non-polymorphic allocators, the alignment is always truncated to the maximum non-extended alignment.

◆ allocateObject()

template<class t_TYPE , class t_ALLOCATOR >

AllocatorUtil_Traits< t_ALLOCATOR, t_TYPE >::pointer bslma::AllocatorUtil::allocateObject	(	const t_ALLOCATOR &	allocator,
		std::size_t	n = `1`
	)

inlinestatic

Return a pointer to a block of raw memory allocated from the specified allocator having a size and alignment appropriate for an object of (templatize parameter) t_TYPE. Optionally specify n for the number of objects; otherwise space for a single object is allocated. Since t_TYPE cannot be deduced from the function parameters, it must be supplied explicitly (in <> brackets) by the caller.

◆ assign() [1/2]

template<class t_TYPE >

t_TYPE & bslma::AllocatorUtil::assign	(	t_TYPE *	lhs,
		const t_TYPE &	rhs,
		bsl::false_type	allowed
	)

inlinestatic

◆ assign() [2/2]

template<class t_TYPE >

t_TYPE & bslma::AllocatorUtil::assign	(	t_TYPE *	lhs,
		const t_TYPE &	rhs,
		bsl::true_type	allowed
	)

inlinestatic

If the specified allowed tag is bsl::true_type assign the allocator object at the specified lhs address the value of the specified rhs; otherwise, do nothing, and, in both cases, return a modifiable reference to *lhs. The t_TYPE template parameter is typically an allocator type and the allowed flag is typically a propagation trait dependant on the calling context, such as propagate_on_container_copy_assignment or propagate_on_container_move_assignment . Instantiation will fail if allowed is true_type and t_TYPE lacks a publically accessible copy assignment operator.

Precondition: The behavior is undefined unless allowed is true_type or *lhs == rhs before the call.

◆ deallocateBytes()

template<class t_ALLOCATOR >

void bslma::AllocatorUtil::deallocateBytes	(	const t_ALLOCATOR &	allocator,
		typename AllocatorUtil_Traits< t_ALLOCATOR >::void_pointer	p,
		std::size_t	nbytes,
		std::size_t	alignment = `0`
	)

inlinestatic

Give back, to the specified allocator, the block of raw memory at the specified p address having the specified nbytes size and optionally specified alignment. If alignment is not specified, the natural alignment for an object of size nbytes is used.

Precondition: The behavior is undefined unless p refers to a block having the same size and alignment previously allocated from a copy of allocator and not yet deallocated.

◆ deallocateObject()

template<class t_ALLOCATOR , class t_POINTER >

void bslma::AllocatorUtil::deallocateObject	(	const t_ALLOCATOR &	allocator,
		t_POINTER	p,
		std::size_t	n = `1`
	)

inlinestatic

Return to the specified allocator a block of raw memory at the specified p address that is suitably sized and aligned to hold an object of (templatize parameter) t_TYPE. Optionally specify n for the number of objects; otherwise a single object is assumed.

Precondition: The behavior is undefined unless p refers to a block with the same type and number of objects previously allocated from a copy of allocator and not yet deallocated.

◆ deleteObject()

template<class t_ALLOCATOR , class t_POINTER >

void bslma::AllocatorUtil::deleteObject	(	const t_ALLOCATOR &	allocator,
		t_POINTER	p
	)

inlinestatic

Destroy the object at the specified p address and return the block of memory at p to the specified allocator.

Precondition: The behavior is undefined unless p refers to a fully constructed object allocated from a copy of allocator and not yet destroyed or deallocated.

◆ newObject() [1/3]

template<class t_TYPE , class t_ALLOCATOR >

AllocatorUtil_Traits< t_ALLOCATOR, t_TYPE >::pointer bslma::AllocatorUtil::newObject ( const t_ALLOCATOR & allocator )

inlinestatic

Return an object of (template parameter) t_TYPE allocated from the specified allocator and constructed with no arguments except that, for scoped allocator types such as bsl::allocator and bsl::polymorphic_allocator, allocator may be passed to the t_TYPE constructor (i.e., if t_TYPE is AA).

◆ newObject() [2/3]

template<class t_TYPE , class t_ALLOCATOR , class t_ARG1 , class... t_ARGS>

AllocatorUtil_Traits< t_ALLOCATOR, t_TYPE >::pointer bslma::AllocatorUtil::newObject	(	const t_ALLOCATOR &	allocator,
		BSLS_COMPILERFEATURES_FORWARD_REF(t_ARG1)	argument1,
		t_ARGS &&...	arguments
	)

inlinestatic

Return an object of (template parameter) t_TYPE allocated from the specified allocator and constructed from the specified argument1 and other specified arguments. For scoped allocator types such as bsl::allocator and bsl::polymorphic_allocator, allocator may be passed to the t_TYPE constructor as an additional argument (i.e., if t_TYPE is AA).

Note: Note that, in C++03, perfect forwarding is limited such that any lvalue reference in the arguments parameter pack is const-qualified when forwarded to the TARGET_TYPE constructor; only argument1 can be forwarded as an unqualified lvalue.

◆ newObject() [3/3]

template<class t_TYPE , class t_ALLOCATOR , class t_ARG1 , class... t_ARGS>

AllocatorUtil_Traits< t_ALLOCATOR, t_TYPE >::pointer bslma::AllocatorUtil::newObject	(	const t_ALLOCATOR &	allocator,
		t_ARG1 &	argument1,
		t_ARGS &&...	arguments
	)

inlinestatic

◆ swap() [1/2]

template<class t_TYPE >

void bslma::AllocatorUtil::swap	(	t_TYPE *	pa,
		t_TYPE *	pb,
		bsl::false_type	allowed
	)

inlinestatic

If the specified allowed tag is bsl::true_type, swap the values of allocators at the specified pa and pb addresses using ADL swap (with std::swap in scope); otherwise, do nothing. The t_TYPE template parameter is typically an allocator type and the allowed flag is typically a propagation trait dependant on the calling context, such as propagate_on_container_swap . Instantiation will fail if allowed is false_type and t_TYPE is not swappable (i.e., because it lacks a publically available assignment operator).

Precondition: The behavior is undefined unless allowed is true_type or '*pa == *pb' before the call.

◆ swap() [2/2]

template<class t_TYPE >

void bslma::AllocatorUtil::swap	(	t_TYPE *	pa,
		t_TYPE *	pb,
		bsl::true_type	allowed
	)

inlinestatic

The documentation for this struct was generated from the following file:

bslma_allocatorutil.h

Detailed Description

Static Public Member Functions

Member Function Documentation

◆ adapt() [1/2]

◆ adapt() [2/2]

◆ allocateBytes()

◆ allocateObject()

◆ assign() [1/2]

◆ assign() [2/2]

◆ deallocateBytes()

◆ deallocateObject()

◆ deleteObject()

◆ newObject() [1/3]

◆ newObject() [2/3]

◆ newObject() [3/3]

◆ swap() [1/2]

◆ swap() [2/2]