v8::String::ExternalStringResourceBase Class Reference

#include <v8-primitive.h>

Inheritance diagram for v8::String::ExternalStringResourceBase:

Classes
class	SharedMemoryUsageRecorder

Public Member Functions
virtual	~ExternalStringResourceBase ()=default
virtual bool	IsCacheable () const
virtual void	Unaccount (Isolate *isolate)
virtual size_t	EstimateMemoryUsage () const
virtual void	EstimateSharedMemoryUsage (SharedMemoryUsageRecorder *recorder) const
	ExternalStringResourceBase (const ExternalStringResourceBase &)=delete
void	operator= (const ExternalStringResourceBase &)=delete

Static Public Attributes
static constexpr size_t	kDefaultMemoryEstimate = static_cast<size_t>(-1)

Protected Member Functions
	ExternalStringResourceBase ()=default
virtual void	Dispose ()
virtual void	Lock () const
virtual void	Unlock () const

Friends
class	internal::ExternalString
class	v8::String
class	internal::StringForwardingTable
class	internal::ScopedExternalStringLock

Constructor & Destructor Documentation

~ExternalStringResourceBase()

virtual v8::String::ExternalStringResourceBase::~ExternalStringResourceBase ( )

virtualdefault

ExternalStringResourceBase() [1/2]

v8::String::ExternalStringResourceBase::ExternalStringResourceBase ( const ExternalStringResourceBase &  )

delete

ExternalStringResourceBase() [2/2]

v8::String::ExternalStringResourceBase::ExternalStringResourceBase ( )

protecteddefault

Member Function Documentation

Dispose()

virtual void v8::String::ExternalStringResourceBase::Dispose ( )

inlineprotectedvirtual

Internally V8 will call this Dispose method when the external string resource is no longer needed. The default implementation will use the delete operator. This method can be overridden in subclasses to control how allocated external string resources are disposed.

EstimateMemoryUsage()

virtual size_t v8::String::ExternalStringResourceBase::EstimateMemoryUsage ( ) const

inlinevirtual

Returns an estimate of the memory occupied by this external string, to be used by V8 when producing a heap snapshot. If this function returns kDefaultMemoryEstimate, then V8 will estimate the external size based on the string length. This function should return only memory that is uniquely owned by this resource. If the resource has shared ownership of a secondary allocation, it can report that memory by implementing EstimateSharedMemoryUsage.

EstimateSharedMemoryUsage()

virtual void v8::String::ExternalStringResourceBase::EstimateSharedMemoryUsage ( SharedMemoryUsageRecorder *  recorder ) const

inlinevirtual

Estimates memory that this string resource may share with other string resources, to be used by V8 when producing a heap snapshot.

IsCacheable()

virtual bool v8::String::ExternalStringResourceBase::IsCacheable ( ) const

inlinevirtual

If a string is cacheable, the value returned by ExternalStringResource::data() may be cached, otherwise it is not expected to be stable beyond the current top-level task.

Lock()

virtual void v8::String::ExternalStringResourceBase::Lock ( ) const

inlineprotectedvirtual

For a non-cacheable string, the value returned by |ExternalStringResource::data()| has to be stable between |Lock()| and |Unlock()|, that is the string must behave as is |IsCacheable()| returned true.

These two functions must be thread-safe, and can be called from anywhere. They also must handle lock depth, in the sense that each can be called several times, from different threads, and unlocking should only happen when the balance of Lock() and Unlock() calls is 0.

operator=()

void v8::String::ExternalStringResourceBase::operator= ( const ExternalStringResourceBase &  )

delete

Unaccount()

virtual void v8::String::ExternalStringResourceBase::Unaccount ( Isolate *  isolate )

inlinevirtual

Internally V8 will call this Unaccount method when the external string resource should be unaccounted for. This method can be overridden in subclasses to control how allocated external bytes are accounted.

Unlock()

virtual void v8::String::ExternalStringResourceBase::Unlock ( ) const

inlineprotectedvirtual

Unlocks the string.

Friends And Related Function Documentation

internal::ExternalString

friend class internal::ExternalString

friend

internal::ScopedExternalStringLock

friend class internal::ScopedExternalStringLock

friend

internal::StringForwardingTable

friend class internal::StringForwardingTable

friend

v8::String

friend class v8::String

friend

Member Data Documentation

kDefaultMemoryEstimate

constexpr size_t v8::String::ExternalStringResourceBase::kDefaultMemoryEstimate = static_cast<size_t>(-1)

staticconstexpr

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

• include/v8-primitive.h