Overview

template<typename ErrorHandler>
class pw::allocator::internal::BasicGuardedAllocator< ErrorHandler >

Generic base class for a GuardedAllocator.

This allocator detects heap overflows by inserting "guard" values before and after the usable allocated memory regions provided to the caller. The value before the usable memory is an offset to the value after, which is a magic value.

Inheritance diagram for pw::allocator::internal::BasicGuardedAllocator< ErrorHandler >:

Protected Member Functions
constexpr	BasicGuardedAllocator (pw::Allocator &allocator)

void *	DoAllocate (Layout layout) override

void	DoDeallocate (void *ptr) override

bool	DoResize (void *ptr, size_t new_size) override

bool	DoBeforeReallocate (void *ptr, Layout new_layout) override

void	DoAfterReallocateCopy (void , Layout, void ) override

Protected Member Functions inherited from pw::allocator::FramingAllocator< void, size_t, ErrorHandler >
constexpr	FramingAllocator (pw::Allocator &allocator)

void *	DoAllocate (Layout layout) override

void	DoDeallocate (void *ptr) override

bool	DoResize (void *ptr, size_t new_size) override

bool	DoBeforeReallocate (void *ptr, Layout new_layout) override

void	DoAfterReallocateCopy (void ptr, Layout new_layout, void new_ptr) override

Result< Layout >	DoGetInfo (Deallocator::InfoType info_type, const void *ptr) const override

void *	GetFrame (void *data) const

const void *	GetFrame (const void *data) const

void *	GetPrefix (void *data) const

const void *	GetPrefix (const void *data) const

void *	GetData (void *frame) const

const void *	GetData (const void *data) const

size_t *	GetSuffix (void *data) const

const size_t *	GetSuffix (const void *data) const

Protected Member Functions inherited from pw::allocator::internal::BaseFramingAllocator< ErrorHandler >
constexpr	BaseFramingAllocator (Allocator &allocator)

ByteSpan	AllocateFrame (Layout prefix, Layout data, Layout suffix)

bool	ResizeFrame (void data, size_t new_size, Layout suffix, void tmp_suffix)

Result< Layout >	GetFrameInfo (InfoType info_type, const void *data, Layout suffix) const

Result< size_t >	GetFrameSize (const void *frame) const

Protected Member Functions inherited from pw::allocator::ForwardingAllocator
constexpr	ForwardingAllocator (const Capabilities &capabilities) noexcept

constexpr	ForwardingAllocator (pw::Allocator &allocator) noexcept

constexpr void	Init (pw::Allocator &allocator)

constexpr pw::Allocator &	allocator ()

constexpr const pw::Allocator &	allocator () const

void *	DoAllocate (Layout layout) override

void	DoDeallocate (void *ptr) override

bool	DoResize (void *ptr, size_t new_size) override

bool	DoBeforeReallocate (void *ptr, Layout new_layout) override

void	DoAfterReallocateCopy (void ptr, Layout new_layout, void new_ptr) override

void	DoAfterReallocateDone (Layout new_layout, void *new_ptr) override

size_t	DoGetAllocated () const override

std::optional< Fragmentation >	DoMeasureFragmentation () const override
	Returns fragmentation information for the allocator's memory region.

Result< Layout >	DoGetInfo (InfoType info_type, const void *ptr) const override

Protected Member Functions inherited from pw::Allocator
constexpr	Allocator () noexcept=default
	TODO(b/326509341): Remove when downstream consumers migrate.

constexpr	Allocator (const Capabilities &capabilities) noexcept

virtual void *	DoAllocate (Layout layout)=0

virtual bool	DoResize (void *ptr, size_t new_size)

virtual void *	DoReallocate (void *ptr, Layout new_layout)

virtual bool	DoBeforeReallocate (void *ptr, Layout new_layout)

virtual void	DoAfterReallocateCopy (void ptr, Layout new_layout, void new_ptr)

virtual void	DoAfterReallocateDone (Layout new_layout, void *new_ptr)

virtual size_t	DoGetAllocated () const

virtual std::optional< Fragmentation >	DoMeasureFragmentation () const
	Returns fragmentation information for the allocator's memory region.

Protected Member Functions inherited from pw::Deallocator
constexpr	Deallocator ()=default
	TODO(b/326509341): Remove when downstream consumers migrate.

constexpr	Deallocator (const Capabilities &capabilities)

Result< Layout >	GetInfo (InfoType info_type, const void *ptr) const

Result< Layout >	GetRequestedLayout (const void *ptr) const

Result< Layout >	GetUsableLayout (const void *ptr) const

Result< Layout >	GetAllocatedLayout (const void *ptr) const

bool	Recognizes (const void *ptr) const

virtual void	DoDeallocate (void *ptr)=0

virtual Result< Layout >	DoGetInfo (InfoType, const void *) const

Friends
template<typename , typename , typename >
class	::pw::allocator::GuardedAllocator

Additional Inherited Members
Public Types inherited from pw::Allocator
using	Fragmentation = allocator::Fragmentation

Public Types inherited from pw::Deallocator
using	Capabilities = allocator::Capabilities

using	Capability = allocator::Capability

using	Layout = allocator::Layout

Public Member Functions inherited from pw::Allocator
void *	Allocate (Layout layout)

template<typename T , int &... kExplicitGuard, std::enable_if_t<!std::is_array_v< T >, int > = 0, typename... Args>
T *	New (Args &&... args)

template<typename T , int &... kExplicitGuard, typename ElementType = std::remove_extent_t<T>, std::enable_if_t< is_bounded_array_v< T >, int > = 0>
ElementType *	New ()

template<typename T , int &... kExplicitGuard, typename ElementType = std::remove_extent_t<T>, std::enable_if_t< is_unbounded_array_v< T >, int > = 0>
ElementType *	New (size_t count)

template<typename T , int &... kExplicitGuard, typename ElementType = std::remove_extent_t<T>, std::enable_if_t< is_unbounded_array_v< T >, int > = 0>
ElementType *	New (size_t count, size_t alignment)
	Constructs an `alignment`-byte aligned array of `count` objects.

template<typename T , int &... kExplicitGuard, std::enable_if_t<!std::is_array_v< T >, int > = 0, typename... Args>
UniquePtr< T >	MakeUnique (Args &&... args)

template<typename T , std::enable_if_t< is_unbounded_array_v< T >, int > = 0>
UniquePtr< T >	MakeUnique (size_t size)

template<typename T , std::enable_if_t< is_unbounded_array_v< T >, int > = 0>
UniquePtr< T >	MakeUnique (size_t size, size_t alignment)

template<typename T , std::enable_if_t< is_bounded_array_v< T >, int > = 0>
UniquePtr< T >	MakeUnique ()

template<typename T , int &... kExplicitGuard, std::enable_if_t<!std::is_array_v< T >, int > = 0, typename... Args>
SharedPtr< T >	MakeShared (Args &&... args)

template<typename T , std::enable_if_t< is_unbounded_array_v< T >, int > = 0>
SharedPtr< T >	MakeShared (size_t size)

template<typename T , std::enable_if_t< is_unbounded_array_v< T >, int > = 0>
SharedPtr< T >	MakeShared (size_t size, size_t alignment)

template<typename T , std::enable_if_t< is_bounded_array_v< T >, int > = 0>
SharedPtr< T >	MakeShared ()

bool	Resize (void *ptr, size_t new_size)

void *	Reallocate (void *ptr, Layout new_layout)

size_t	GetAllocated () const

std::optional< Fragmentation >	MeasureFragmentation () const
	Returns fragmentation information for the allocator's memory region.

Public Member Functions inherited from pw::Deallocator
constexpr const Capabilities &	capabilities () const

constexpr bool	HasCapability (Capability capability) const
	Returns whether a given capability is enabled for this object.

void	Deallocate (void *ptr)

template<typename ElementType >
void	DeleteArray (ElementType *ptr, size_t count)

template<typename ElementType >
void	Destroy (ElementType *ptr, size_t count)

StatusWithSize	GetCapacity () const

bool	IsEqual (const Deallocator &other) const

template<typename T , int &... kExplicitGuard, std::enable_if_t<!std::is_array_v< T >, int > = 0>
void	Delete (T *ptr)

template<typename T , int &... kExplicitGuard, typename ElementType = std::remove_extent_t<T>, std::enable_if_t< is_bounded_array_v< T >, int > = 0>
void	Delete (ElementType *ptr)

template<typename T , int &... kExplicitGuard, typename ElementType = std::remove_extent_t<T>, std::enable_if_t< is_unbounded_array_v< T >, int > = 0>
void	Delete (ElementType *ptr, size_t count)

Protected Types inherited from pw::allocator::FramingAllocator< void, size_t, ErrorHandler >
using	Base = internal::BaseFramingAllocator< ErrorHandler >

Protected Types inherited from pw::Deallocator
enum class	InfoType { kRequestedLayoutOf , kUsableLayoutOf , kAllocatedLayoutOf , kCapacity , kRecognizes }

Static Protected Member Functions inherited from pw::allocator::internal::BaseFramingAllocator< ErrorHandler >
static constexpr size_t	Distance (const void start, const void end)
	Returns the distance between two pointers in bytes.

static void	UpdateOffsets (void frame, void data, void *suffix)

static void *	GetFrame (void *data, bool has_suffix, bool checked=true)

static const void *	GetFrame (const void *data, bool has_suffix, bool checked=true)

static void *	GetData (void *frame, Result< size_t > frame_size, Layout prefix)

static const void *	GetData (const void *frame, Result< size_t > frame_size, Layout prefix)

static void *	GetSuffix (void *data, size_t data_size, Layout suffix)

static const void *	GetSuffix (const void *data, size_t data_size, Layout suffix)

Static Protected Member Functions inherited from pw::Allocator
static bool	BeforeReallocate (Allocator &allocator, void *ptr, Layout new_layout)

static void	AfterReallocateCopy (Allocator &allocator, void ptr, Layout new_layout, void new_ptr)

static void	AfterReallocateDone (Allocator &allocator, Layout new_layout, void *new_ptr)

Static Protected Member Functions inherited from pw::Deallocator
static Result< Layout >	GetInfo (const Deallocator &deallocator, InfoType info_type, const void *ptr)

static Result< Layout >	GetRequestedLayout (const Deallocator &deallocator, const void *ptr)

static Result< Layout >	GetUsableLayout (const Deallocator &deallocator, const void *ptr)

static Result< Layout >	GetAllocatedLayout (const Deallocator &deallocator, const void *ptr)

static bool	Recognizes (const Deallocator &deallocator, const void *ptr)

Static Protected Attributes inherited from pw::Deallocator
template<typename T >
static constexpr bool	is_bounded_array_v = ::pw::is_bounded_array_v<T>

template<typename T >
static constexpr bool	is_unbounded_array_v = ::pw::is_unbounded_array_v<T>

Member Function Documentation

◆ DoAfterReallocateCopy()

template<typename ErrorHandler >

void pw::allocator::internal::BasicGuardedAllocator< ErrorHandler >::DoAfterReallocateCopy	(	void *	,
		Layout	,
		void *
	)

inlineoverrideprotectedvirtual

Static version of DoAfterReallocateCopy that allows forwarding allocators to call it on wrapped allocators.

The call to Allocate sets the correct suffix, so this override simply prevents FramingAllocator::DoAfterReallocateCopy from clobbering it.

Reimplemented from pw::allocator::ForwardingAllocator.

◆ DoAllocate()

template<typename ErrorHandler >

void * pw::allocator::internal::BasicGuardedAllocator< ErrorHandler >::DoAllocate ( Layout layout )

overrideprotectedvirtual

Allocates a block of memory with the specified size and alignment.

Returns nullptr if the allocation cannot be made, or the layout has a size of 0.

Parameters

[in] layout Describes the memory to be allocated.

Reimplemented from pw::allocator::ForwardingAllocator.

◆ DoBeforeReallocate()

template<typename ErrorHandler >

bool pw::allocator::internal::BasicGuardedAllocator< ErrorHandler >::DoBeforeReallocate	(	void *	ptr,
		Layout	new_layout
	)

overrideprotectedvirtual

Static version of DoBeforeReallocate that allows forwarding allocators to call it on wrapped allocators.

Reimplemented from pw::allocator::ForwardingAllocator.

◆ DoDeallocate()

template<typename ErrorHandler >

void pw::allocator::internal::BasicGuardedAllocator< ErrorHandler >::DoDeallocate ( void * ptr )

overrideprotectedvirtual

Releases a previously-allocated block of memory.

The given pointer must have been previously provided by this memory resource; otherwise the behavior is undefined.

Parameters

[in] ptr Pointer to previously-allocated memory.

Reimplemented from pw::allocator::ForwardingAllocator.

◆ DoResize()

template<typename ErrorHandler >

bool pw::allocator::internal::BasicGuardedAllocator< ErrorHandler >::DoResize	(	void *	ptr,
		size_t	new_size
	)

overrideprotectedvirtual

Modifies the size of an previously-allocated block of memory without copying any data.

Returns true if its size was changed without copying data to a new allocation; otherwise returns false.

In particular, it always returns true if the old_layout.size() equals new_size, and always returns false if the given pointer is null, the old_layout.size() is 0, or the new_size is 0.

Parameters

[in]	ptr	Pointer to previously-allocated memory.
[in]	new_size	Requested new size for the memory allocation.

Reimplemented from pw::allocator::ForwardingAllocator.

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

pw_allocator/public/pw_allocator/guarded_allocator.h

Overview

Protected Member Functions

Friends

Additional Inherited Members

Member Function Documentation

◆ DoAfterReallocateCopy()

◆ DoAllocate()

◆ DoBeforeReallocate()

◆ DoDeallocate()

◆ DoResize()