kanzi::ReadOnlyMemoryFile Class Reference

The ReadOnlyMemoryFile class provides a (read-only) file interface to a block of memory. More...

#include <kanzi/core/file/read_only_memory_file.hpp>

Inheritance diagram for kanzi::ReadOnlyMemoryFile:

Public Member Functions
const byte *	map () override
	Maps the contents of a file to the process memory. More...
void	read (char *buffer, uintmax_t count) override
	Reads data from a file. More...
	ReadOnlyMemoryFile (const byte *buffer, uintmax_t size)
void	seek (SeekPosition position, intmax_t offset) override
	Sets the position in a file. More...
uintmax_t	size () const override
	Gets the size of a file. More...
uintmax_t	tell () const override
	Gets the current position in a file. More...
KZ_NO_DISCARD uintmax_t	tryRead (char *buffer, uintmax_t count) override
	Tries to reads data from a file. More...
void	write (const char *, uintmax_t) override
	Writes data to a file. More...
	~ReadOnlyMemoryFile () override=default
Public Member Functions inherited from kanzi::File
virtual	~File ()
	Destructor. More...

Additional Inherited Members
Public Types inherited from kanzi::File
enum	SeekPosition { SeekBegin, SeekCurrent }
	Seek origin enumeration for seek(). More...
Protected Member Functions inherited from kanzi::File
	File ()

Detailed Description

The ReadOnlyMemoryFile class provides a (read-only) file interface to a block of memory.

It is constructed from a size and a pointer to the memory block. You need to make sure that the memory block remains valid while the ReadOnlyMemoryFile is being used.

Constructor & Destructor Documentation

ReadOnlyMemoryFile()

kanzi::ReadOnlyMemoryFile::ReadOnlyMemoryFile ( const byte *  buffer, uintmax_t  size  )

inlineexplicit

~ReadOnlyMemoryFile()

kanzi::ReadOnlyMemoryFile::~ReadOnlyMemoryFile ( )

overridedefault

Member Function Documentation

read()

void kanzi::ReadOnlyMemoryFile::read ( char *  buffer, uintmax_t  count  )

overridevirtual

Reads data from a file.

The function starts reading at the current file position. When you call read(), it invalidates the pointer returned by map(). This function throws when its can't read count number of bytes from the File.

Parameters

buffer	Buffer to which to read. The size of the buffer in bytes must be at least the size of the value you pass in the count parameter.
count	Number of bytes to read.

See also

write(), tell(), and map().

Implements kanzi::File.

tryRead()

KZ_NO_DISCARD uintmax_t kanzi::ReadOnlyMemoryFile::tryRead ( char *  buffer, uintmax_t  count  )

overridevirtual

Tries to reads data from a file.

The function starts reading at the current file position. When you call tryRead(), it invalidates the pointer returned by map().

Parameters

buffer	Buffer to which to read. The size of the buffer in bytes must be at least the size of the value you pass in the count parameter.
count	Number of bytes to read.

See also

write(), tell(), and map().

Returns

Returns the number of bytes read.

Implements kanzi::File.

write()

void kanzi::ReadOnlyMemoryFile::write ( const char *  buffer, uintmax_t  count  )

overridevirtual

Writes data to a file.

The function starts writing at the current file position. When you call write(), it invalidates the pointer returned by map().

Parameters

buffer	Buffer from which to write. The size of the buffer in bytes must be at least the size of the value you pass in the count parameter.
count	Number of bytes to write.

See also

read(), tell(), and map().

Implements kanzi::File.

size()

uintmax_t kanzi::ReadOnlyMemoryFile::size ( ) const

overridevirtual

Gets the size of a file.

Returns

Returns the size of a file in bytes.

Implements kanzi::File.

tell()

uintmax_t kanzi::ReadOnlyMemoryFile::tell ( ) const

overridevirtual

Gets the current position in a file.

Returns

Returns the position in a file in bytes.

See also

seek(), read(), and write().

Implements kanzi::File.

seek()

void kanzi::ReadOnlyMemoryFile::seek ( SeekPosition  position, intmax_t  offset  )

overridevirtual

Sets the position in a file.

You can set the position as an offset to either the current position or the beginning of the file. When you call seek(), it invalidates the pointer returned by map().

Parameters

position	Seek origin.
offset	Offset in bytes from the seek origin.

See also

SeekPosition and tell().

Implements kanzi::File.

map()

const byte* kanzi::ReadOnlyMemoryFile::map ( )

overridevirtual

Maps the contents of a file to the process memory.

When you call read(), write(), or seek(), these functions invalidate the pointer returned by map().

Returns

Returns the pointer to the beginning of a file.

See also

read(), write(), and seek().

Implements kanzi::File.

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

• kanzi/core/file/read_only_memory_file.hpp