AZ::IO::FullFileDecompressor Class Reference

#include <FullFileDecompressor.h>

Inherits AZ::IO::StreamStackEntry.

Public Member Functions
	FullFileDecompressor (u32 maxNumReads, u32 maxNumJobs, u32 alignment)
void	PrepareRequest (FileRequest *request) override
void	QueueRequest (FileRequest *request) override
bool	ExecuteRequests () override
void	UpdateStatus (Status &status) const override
	Gets a combined status update from all the nodes in the stack.
void	UpdateCompletionEstimates (AZStd::chrono::steady_clock::time_point now, AZStd::vector< FileRequest * > &internalPending, StreamerContext::PreparedQueue::iterator pendingBegin, StreamerContext::PreparedQueue::iterator pendingEnd) override
void	CollectStatistics (AZStd::vector< Statistic > &statistics) const override
Public Member Functions inherited from AZ::IO::StreamStackEntry
	StreamStackEntry (AZStd::string &&name)
virtual const AZStd::string &	GetName () const
	Returns the name that uniquely identifies this entry.
virtual void	SetNext (AZStd::shared_ptr< StreamStackEntry > next)
virtual AZStd::shared_ptr< StreamStackEntry >	GetNext () const
virtual void	SetContext (StreamerContext &context)
virtual void	PrepareRequest (FileRequest *request)
virtual void	QueueRequest (FileRequest *request)
virtual bool	ExecuteRequests ()
virtual void	UpdateStatus (Status &status) const
	Gets a combined status update from all the nodes in the stack.
virtual void	UpdateCompletionEstimates (AZStd::chrono::steady_clock::time_point now, AZStd::vector< FileRequest * > &internalPending, StreamerContext::PreparedQueue::iterator pendingBegin, StreamerContext::PreparedQueue::iterator pendingEnd)
virtual void	CollectStatistics (AZStd::vector< Statistic > &statistics) const

Additional Inherited Members
Protected Attributes inherited from AZ::IO::StreamStackEntry
AZStd::string	m_name
	The name that uniquely identifies this entry.
AZStd::shared_ptr< StreamStackEntry >	m_next
	The next entry in the stack.
StreamerContext *	m_context
	Context information for the entire streaming stack.

Detailed Description

Entry in the streaming stack that decompresses files from an archive that are stored as single files and without equally distributed seek points. Because the target archive has compressed the entire file, it needs to be decompressed completely, so even if the file is partially read, it needs to be fully loaded. This also means that there's no upper limit to the memory so every decompression job will need to allocate memory as a temporary buffer (in-place decompression is not supported). Finally, the lack of an upper limit also means that the duration of the decompression job can vary largely so a dedicated job system is used to decompress on to avoid blocking the main job system from working.

Member Function Documentation

CollectStatistics()

void AZ::IO::FullFileDecompressor::CollectStatistics ( AZStd::vector< Statistic > &  statistics ) const

overridevirtual

Collect various statistics on this stack entry. These are for profiling and debugging purposes only.

Reimplemented from AZ::IO::StreamStackEntry.

ExecuteRequests()

bool AZ::IO::FullFileDecompressor::ExecuteRequests ( )

overridevirtual

Executes one or more queued requests. This is needed for synchronously executing requests, but asynchronous requests can already be running from the PrepareRequest call in which case this call is ignored.

Returns

True if a request was processed, otherwise false.

Reimplemented from AZ::IO::StreamStackEntry.

PrepareRequest()

void AZ::IO::FullFileDecompressor::PrepareRequest ( FileRequest *  request )

overridevirtual

Prepare an external request for processing. This can include resolving file paths, create more specific internal requests, etc. The returned will be queued for further processing by QueueRequest and ExecuteRequest.

Reimplemented from AZ::IO::StreamStackEntry.

QueueRequest()

void AZ::IO::FullFileDecompressor::QueueRequest ( FileRequest *  request )

overridevirtual

Queues a request to be executed at a later point when ExecuteRequests is called. This can include splitting up the request in more fine-grained steps.

Reimplemented from AZ::IO::StreamStackEntry.

UpdateCompletionEstimates()

void AZ::IO::FullFileDecompressor::UpdateCompletionEstimates ( AZStd::chrono::steady_clock::time_point  now, AZStd::vector< FileRequest * > &  internalPending, StreamerContext::PreparedQueue::iterator  pendingBegin, StreamerContext::PreparedQueue::iterator  pendingEnd  )

overridevirtual

Updates the estimate of the time the requests will complete. This generally works by bubbling up the estimation and each stack entry adding it's additional overhead if any. When chaining this call, first call the next entry in the stack before adding the current entry's estimate.

Parameters

now	The current time. This is captured once to avoid repeatedly querying the system clock.
internalPending	The requests that are pending in the stream stack. These are always estimated as coming after the queued requests. Because this call will go from the top of the stack to the bottom, but estimation is calculated from the bottom to the top, this list should be processed in reverse order.
pendingBegin	Iterator pointing to the start of the requests that are waiting for a processing slot in the stack.
pendingEnd	Iterator pointing to the end of the requests that are waiting for a processing slot in the stack.

Reimplemented from AZ::IO::StreamStackEntry.

UpdateStatus()

void AZ::IO::FullFileDecompressor::UpdateStatus ( Status &  status ) const

overridevirtual

Gets a combined status update from all the nodes in the stack.

Reimplemented from AZ::IO::StreamStackEntry.

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

• Code/Framework/AzCore/AzCore/IO/Streamer/FullFileDecompressor.h