RandomAccessFile Class Reference

A file from which bytes, words and double words are read in (potentially) a random order. More...

#include <random_access_file_type.h>

Inheritance diagram for RandomAccessFile:

Public Member Functions
	RandomAccessFile (const std::string &filename, Subdirectory subdir)
	Create the RandomAccesFile. More...
	RandomAccessFile (const RandomAccessFile &)=delete
void	operator= (const RandomAccessFile &)=delete
const std::string &	GetFilename () const
	Get the filename of the opened file with the path from the SubDirectory and the extension. More...
const std::string &	GetSimplifiedFilename () const
	Get the simplified filename of the opened file. More...
size_t	GetPos () const
	Get position in the file. More...
size_t	GetStartPos () const
size_t	GetEndPos () const
void	SeekTo (size_t pos, int mode)
	Seek in the current file. More...
bool	AtEndOfFile () const
	Test if we have reached the end of the file. More...
uint8_t	ReadByte ()
	Read a byte from the file. More...
uint16_t	ReadWord ()
	Read a word (16 bits) from the file (in low endian format). More...
uint32_t	ReadDword ()
	Read a double word (32 bits) from the file (in low endian format). More...
void	ReadBlock (void *ptr, size_t size)
	Read a block. More...
void	SkipBytes (size_t n)
	Skip n bytes ahead in the file. More...

Private Attributes
std::string	filename
	Full name of the file; relative path to subdir plus the extension of the file.
std::string	simplified_filename
	Simplified lowecase name of the file; only the name, no path or extension.
std::optional< FileHandle >	file_handle
	File handle of the open file.
size_t	pos
	Position in the file of the end of the read buffer.
size_t	start_pos
	Start position of file. May be non-zero if file is within a tar file.
size_t	end_pos
	End position of file.
uint8_t *	buffer
	Current position within the local buffer.
uint8_t *	buffer_end
	Last valid byte of buffer.
uint8_t	buffer_start [BUFFER_SIZE]
	Local buffer when read from file.

Static Private Attributes
static constexpr int	BUFFER_SIZE = 512
	The number of bytes to allocate for the buffer.

Detailed Description

A file from which bytes, words and double words are read in (potentially) a random order.

This is mostly intended to be used for things that can be read from GRFs when needed, so the graphics but also the sounds. This also ties into the spritecache as it uses these files to load the sprites from when needed.

Definition at line 22 of file random_access_file_type.h.

Constructor & Destructor Documentation

RandomAccessFile()

RandomAccessFile::RandomAccessFile	(	const std::string &	filename,
		Subdirectory	subdir
	)

Create the RandomAccesFile.

Parameters

filename	Name of the file at the disk.
subdir	The sub directory to search this file in.

Definition at line 25 of file random_access_file.cpp.

References file_handle, and FioFOpenFile().

Member Function Documentation

AtEndOfFile()

bool RandomAccessFile::AtEndOfFile

(

)

const

Test if we have reached the end of the file.

Returns

True iff the current position as at or after the end of the file.

Definition at line 80 of file random_access_file.cpp.

References GetPos().

GetFilename()

const std::string & RandomAccessFile::GetFilename

(

)

const

Get the filename of the opened file with the path from the SubDirectory and the extension.

Returns

Name of the file.

Definition at line 52 of file random_access_file.cpp.

References filename.

GetPos()

size_t RandomAccessFile::GetPos

(

)

const

Get position in the file.

Returns

Position in the file.

Definition at line 71 of file random_access_file.cpp.

References buffer, buffer_end, and pos.

Referenced by AtEndOfFile(), GetGRFContainerVersion(), LoadNewGRFSound(), LoadNextSprite(), ReadBlock(), ReadGRFSpriteOffsets(), SeekTo(), and SpriteFile::SpriteFile().

GetSimplifiedFilename()

const std::string & RandomAccessFile::GetSimplifiedFilename

(

)

const

Get the simplified filename of the opened file.

The simplified filename is the name of the file without the SubDirectory or extension in lower case.

Returns

Name of the file.

Definition at line 62 of file random_access_file.cpp.

References simplified_filename.

Referenced by LoadNewGRFSound(), and WarnCorruptSprite().

ReadBlock()

void RandomAccessFile::ReadBlock	(	void *	ptr,
		size_t	size
	)

Read a block.

Parameters

ptr	Destination buffer.
size	Number of bytes to read.

Definition at line 145 of file random_access_file.cpp.

References file_handle, GetPos(), pos, and SeekTo().

Referenced by GetMusicCatEntryData(), GetMusicCatEntryName(), LoadNewGRFSound(), and ReadRecolourSprite().

ReadByte()

uint8_t RandomAccessFile::ReadByte

(

)

Read a byte from the file.

Returns

Read byte.

Definition at line 107 of file random_access_file.cpp.

References buffer, buffer_end, BUFFER_SIZE, buffer_start, file_handle, and pos.

Referenced by DecodeSingleSprite(), GetGRFContainerVersion(), GetMusicCatEntryData(), GetMusicCatEntryName(), LoadNewGRFSound(), LoadNextSprite(), and ReadGRFSpriteOffsets().

ReadDword()

uint32_t RandomAccessFile::ReadDword

(

)

Read a double word (32 bits) from the file (in low endian format).

Returns

Read word.

Definition at line 134 of file random_access_file.cpp.

References ReadWord().

Referenced by GetMusicCatEntryData(), GetMusicCatEntryName(), LoadNewGRFSound(), LoadNextSprite(), and ReadGRFSpriteOffsets().

ReadWord()

uint16_t RandomAccessFile::ReadWord

(

)

Read a word (16 bits) from the file (in low endian format).

Returns

Read word.

Definition at line 124 of file random_access_file.cpp.

Referenced by GetGRFContainerVersion(), LoadNewGRFSound(), LoadNextSprite(), and ReadDword().

SeekTo()

void RandomAccessFile::SeekTo	(	size_t	pos,
		int	mode
	)

Seek in the current file.

Parameters

pos	New position.
mode	Type of seek (SEEK_CUR means pos is relative to current position, SEEK_SET means pos is absolute).

Definition at line 90 of file random_access_file.cpp.

References buffer, buffer_end, buffer_start, Debug, file_handle, filename, GetPos(), and pos.

Referenced by GetGRFContainerVersion(), GetMusicCatEntryData(), GetMusicCatEntryName(), LoadNewGRFSound(), ReadBlock(), ReadGRFSpriteOffsets(), SpriteFile::SeekToBegin(), and SkipBytes().

SkipBytes()

void RandomAccessFile::SkipBytes

(

size_t

n

)

Skip n bytes ahead in the file.

Parameters

n	Number of bytes to skip reading.

Definition at line 155 of file random_access_file.cpp.

References buffer, buffer_end, and SeekTo().

Referenced by GetMusicCatEntryData(), LoadNewGRFSound(), LoadNextSprite(), and ReadGRFSpriteOffsets().

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

• src/random_access_file_type.h
• src/random_access_file.cpp