DD::Image::FileWriter Class Reference

Inherits DD::Image::Writer.

List of all members.

Public Member Functions
	FileWriter (Write *)
	~FileWriter ()
virtual void	finish ()
	Called when processing is finished for the current file.
Protected Member Functions
bool	open ()
bool	close ()
bool	write (const void *, FILE_OFFSET)
bool	write (FILE_OFFSET, const void *, FILE_OFFSET)
bool	seek (FILE_OFFSET)
FILE_OFFSET	tell () const
std::string	getTempFileName (const char *pActualFileName=NULL) const
	Returns a temporary file name for the current output file (e. g. filename.ext.tmp)
Protected Attributes
void *	file
	Actually a FILE* but I don't want the <stdio.h> header!
FILE_OFFSET	offset
	Current offset into file.
Related Functions
(Note that these are not member functions.)
typedef unsigned long	FILE_OFFSET
typedef unsigned long	FILE_OFFSET

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Detailed Description

Writer subclass to write a single Unix file. You must subclass this and implement several virtual functions to write pieces of a file. This takes care of opening and closing the file.

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Constructor & Destructor Documentation

FileWriter::FileWriter

(

Write *

iop

)

This does not open the file. Instead a subclass should call open() as the first statement in execute() and then return if open fails.

References file.

FileWriter::~FileWriter

(

)

Destruction closes the temporary file if execute() did not call close().

References file.

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Member Function Documentation

bool FileWriter::open

(

)

[protected]

Open the output file. This file is created with a temporary name so that the original file is not replaced until the write is successful. This returns false and calls iop->error() if it can't open the file.

References DD::Image::Op::critical(), file, DD::Image::Writer::filename(), getTempFileName(), DD::Image::Writer::iop, and offset.

bool FileWriter::close

(

)

[protected]

Close the output file. If there have not been any errors this will mv the temporary file to the correct place.

References DD::Image::Writer::aborted(), DD::Image::Op::critical(), file, DD::Image::Writer::filename(), getTempFileName(), and DD::Image::Writer::iop.

bool FileWriter::write	(	const void *	buf,
		FILE_OFFSET	length
	)		[protected]

Write length bytes to the file. Call iop->error() on any errors and returns false. Returns true on success.

References DD::Image::Op::critical(), file, DD::Image::Writer::iop, and offset.

Referenced by write().

bool FileWriter::write	(	FILE_OFFSET	off,
		const void *	buf,
		FILE_OFFSET	length
	)		[protected]

Same as "seek(off) && write(buf, length)", this writes length bytes to the file at offset and leaves the pointer after that.

References seek(), and write().

bool FileWriter::seek

(

FILE_OFFSET

off

)

[protected]

Move the write pointer to offset. This is done efficiently if the pointer is already at that point. Calls iop->error() on any errors and returns false. Returns true on success.

References DD::Image::Op::critical(), file, DD::Image::Writer::iop, and offset.

Referenced by write().

FILE_OFFSET DD::Image::FileWriter::tell

(

)

const [inline, protected]

Returns where the pointer currently is.

std::string FileWriter::getTempFileName

(

const char *

pActualFileName = NULL

)

const [protected]

Returns a temporary file name for the current output file (e. g. filename.ext.tmp)

Returns a temporary file name for the given actual file name. e. g. filename.ext -> filename.ext.tmp Pass in NULL to use the current filename().

References DD::Image::Writer::filename().

Referenced by close(), finish(), and open().

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Friends And Related Function Documentation

typedef unsigned long FILE_OFFSET [related]

This type may need to be replaced on 64-bit file systems.

typedef unsigned long FILE_OFFSET [related]

This type may need to be replaced on 64-bit file systems.