ProtoOutputStream Class Reference

A ProtoOutputStream wraps a coded stream, potentially with compression, based on looking at the file name. More...

#include <protoio.hh>

Inheritance diagram for ProtoOutputStream:

Public Member Functions
	ProtoOutputStream (const std::string &filename)
	Create an output stream for a given file name. More...
	~ProtoOutputStream ()
	Destruct the output stream, and also flush and close the underlying file streams and coded streams. More...
void	write (const google::protobuf::Message &msg)
	Write a message to the stream, preprending it with the message size. More...

Private Attributes
std::ofstream	fileStream
	Underlying file output stream. More...
google::protobuf::io::OstreamOutputStream *	wrappedFileStream
	Zero Copy stream wrapping the STL output stream. More...
google::protobuf::io::GzipOutputStream *	gzipStream
	Optional Gzip stream to wrap the Zero Copy stream. More...
google::protobuf::io::ZeroCopyOutputStream *	zeroCopyStream
	Top-level zero-copy stream, either with compression or not. More...

Additional Inherited Members
Protected Member Functions inherited from ProtoStream
	ProtoStream ()
	Create a ProtoStream. More...
Static Protected Attributes inherited from ProtoStream
static const uint32_t	magicNumber = 0x356d6567
	Use the ASCII characters gem5 as our magic number. More...

Detailed Description

A ProtoOutputStream wraps a coded stream, potentially with compression, based on looking at the file name.

Writing to the stream is done to enable interaction with the file on a per-message basis to avoid having to deal with huge data structures. The latter is made possible by encoding the length of each message in the stream.

Definition at line 92 of file protoio.hh.

Constructor & Destructor Documentation

ProtoOutputStream::ProtoOutputStream

(

const std::string &

filename

)

Create an output stream for a given file name.

If the filename ends with .gz then the file will be compressed accordinly.

Parameters

filename

Path to the file to create or truncate

Definition at line 47 of file protoio.cc.

References fileStream, gzipStream, ProtoStream::magicNumber, panic, wrappedFileStream, and zeroCopyStream.

ProtoOutputStream::~ProtoOutputStream

(

)

Destruct the output stream, and also flush and close the underlying file streams and coded streams.

Definition at line 74 of file protoio.cc.

References fileStream, gzipStream, and wrappedFileStream.

Member Function Documentation

void ProtoOutputStream::write

(

const google::protobuf::Message &

msg

)

Write a message to the stream, preprending it with the message size.

Parameters

msg	Message to write to the stream

Definition at line 84 of file protoio.cc.

References zeroCopyStream.

Referenced by Trace::InstPBTrace::closeStreams(), Trace::InstPBTrace::createTraceFile(), ElasticTrace::ElasticTrace(), ElasticTrace::fetchReqTrace(), MemTraceProbe::handleRequest(), MemTraceProbe::MemTraceProbe(), Trace::InstPBTrace::traceInst(), and ElasticTrace::writeDepTrace().

Member Data Documentation

std::ofstream ProtoOutputStream::fileStream

private

Underlying file output stream.

Definition at line 122 of file protoio.hh.

Referenced by ProtoOutputStream(), and ~ProtoOutputStream().

google::protobuf::io::GzipOutputStream* ProtoOutputStream::gzipStream

private

Optional Gzip stream to wrap the Zero Copy stream.

Definition at line 128 of file protoio.hh.

Referenced by ProtoOutputStream(), and ~ProtoOutputStream().

google::protobuf::io::OstreamOutputStream* ProtoOutputStream::wrappedFileStream

private

Zero Copy stream wrapping the STL output stream.

Definition at line 125 of file protoio.hh.

Referenced by ProtoOutputStream(), and ~ProtoOutputStream().

google::protobuf::io::ZeroCopyOutputStream* ProtoOutputStream::zeroCopyStream

private

Top-level zero-copy stream, either with compression or not.

Definition at line 131 of file protoio.hh.

Referenced by ProtoOutputStream(), and write().

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

• proto/protoio.hh
• proto/protoio.cc