File opening, unlinking, and closing. More...

#include "private.h"
#include <fcntl.h>
#include "tuklib_open_stdxxx.h"

Defines
#define	O_BINARY 0
#define	O_NOCTTY 0
Functions
static bool	io_write_buf (file_pair pair, const uint8_t buf, size_t size)
void	io_init (void)
	Initialize the I/O module.
void	io_no_sparse (void)
	Disable creation of sparse files when decompressing.
static void	io_unlink (const char name, const struct stat known_st)
	Unlink a file.
static void	io_copy_attrs (const file_pair *pair)
	Copies owner/group and permissions.
static bool	io_open_src_real (file_pair *pair)
	Opens the source file. Returns false on success, true on error.
file_pair *	io_open_src (const char *src_name)
	Open the source file.
static void	io_close_src (file_pair *pair, bool success)
	Closes source file of the file_pair structure.
static bool	io_open_dest_real (file_pair *pair)
bool	io_open_dest (file_pair *pair)
	Open the destination file.
static bool	io_close_dest (file_pair *pair, bool success)
	Closes destination file of the file_pair structure.
void	io_close (file_pair *pair, bool success)
	Closes the file descriptors and frees possible allocated memory.
size_t	io_read (file_pair pair, io_buf buf_union, size_t size)
	Reads from the source file to a buffer.
bool	io_pread (file_pair pair, io_buf buf, size_t size, off_t pos)
	Read from source file from given offset to a buffer.
static bool	is_sparse (const io_buf *buf)
bool	io_write (file_pair pair, const io_buf buf, size_t size)
	Writes a buffer to the destination file.
Variables
static bool	warn_fchown
static bool	try_sparse = true
	If true, try to create sparse files when decompressing.
static int	stdout_flags = 0

Detailed Description

File opening, unlinking, and closing.

Function Documentation

void io_init ( void )

Initialize the I/O module.

void io_no_sparse ( void )

Disable creation of sparse files when decompressing.

References try_sparse.

static void io_unlink	(	const char *	name,
		const struct stat *	known_st
	)			`[static]`

Unlink a file.

This tries to verify that the file being unlinked really is the file that we want to unlink by verifying device and inode numbers. There's still a small unavoidable race, but this is much better than nothing (the file could have been moved/replaced even hours earlier).

References message_error().

Referenced by io_close_dest(), and io_close_src().

static void io_copy_attrs ( const file_pair * pair ) [static]

Copies owner/group and permissions.

Todo:: ACL and EA support

References file_pair::dest_fd, file_pair::dest_name, message_warning(), and file_pair::src_st.

Referenced by io_close().

static bool io_open_src_real ( file_pair * pair ) [static]

Opens the source file. Returns false on success, true on error.

References message_error(), message_warning(), signals_block(), signals_unblock(), file_pair::src_fd, file_pair::src_name, file_pair::src_st, and user_abort.

Referenced by io_open_src().

file_pair* io_open_src ( const char * src_name )

Open the source file.

References io_open_src_real(), is_empty_filename(), signals_block(), signals_unblock(), and file_pair::src_name.

Referenced by coder_run(), and list_file().

static void io_close_src	(	file_pair *	pair,
		bool	success
	)			`[static]`

Closes source file of the file_pair structure.

Parameters:

	pair	File whose src_fd should be closed
	success	If true, the file will be removed from the disk if closing succeeds and --keep hasn't been used.

References io_unlink(), file_pair::src_fd, file_pair::src_name, and file_pair::src_st.

Referenced by io_close().

bool io_open_dest ( file_pair * pair )

Open the destination file.

References signals_block(), and signals_unblock().

Referenced by coder_run().

static bool io_close_dest	(	file_pair *	pair,
		bool	success
	)			`[static]`

Closes destination file of the file_pair structure.

Parameters:

	pair	File whose dest_fd should be closed
	success	If false, the file will be removed from the disk.

Returns:: Zero if closing succeeds. On error, -1 is returned and error message printed.

References file_pair::dest_fd, file_pair::dest_name, file_pair::dest_st, io_unlink(), message_error(), and stdout_flags.

Referenced by io_close().

void io_close	(	file_pair *	pair,
		bool	success
	)

Closes the file descriptors and frees possible allocated memory.

The success argument determines if source or destination file gets unlinked:

false: The destination file is unlinked.
true: The source file is unlinked unless writing to stdout or --keep was used.

References file_pair::dest_fd, file_pair::dest_name, file_pair::dest_pending_sparse, file_pair::dest_try_sparse, io_close_dest(), io_close_src(), io_copy_attrs(), message_error(), signals_block(), and signals_unblock().

Referenced by coder_run(), and list_file().

size_t io_read	(	file_pair *	pair,
		io_buf *	buf,
		size_t	size
	)

Reads from the source file to a buffer.

Parameters:

	pair	File pair having the source file open for reading
	buf	Destination buffer to hold the read data
	size	Size of the buffer; assumed be smaller than SSIZE_MAX

Returns:: On success, number of bytes read is returned. On end of file zero is returned and pair->src_eof set to true. On error, SIZE_MAX is returned and error message printed.

References message_error(), file_pair::src_eof, file_pair::src_fd, file_pair::src_name, and user_abort.

Referenced by coder_normal(), coder_passthru(), coder_run(), and io_pread().

bool io_pread	(	file_pair *	pair,
		io_buf *	buf,
		size_t	size,
		off_t	pos
	)

Read from source file from given offset to a buffer.

This is remotely similar to standard pread(). This uses lseek() though, so the read offset is changed on each call.

Parameters:

	pair	Seekable source file
	buf	Destination buffer
	size	Amount of data to read
	pos	Offset relative to the beginning of the file, from which the data should be read.

Returns:: On success, false is returned. On error, error message is printed and true is returned.

References io_read(), message_error(), file_pair::src_fd, and file_pair::src_name.

Referenced by parse_block_header(), parse_check_value(), and parse_indexes().

bool io_write	(	file_pair *	pair,
		const io_buf *	buf,
		size_t	size
	)

Writes a buffer to the destination file.

Parameters:

	pair	File pair having the destination file open for writing
	buf	Buffer containing the data to be written
	size	Size of the buffer; assumed be smaller than SSIZE_MAX

Returns:: On success, zero is returned. On error, -1 is returned and error message printed.

References file_pair::dest_fd, file_pair::dest_name, file_pair::dest_pending_sparse, file_pair::dest_try_sparse, and message_error().

Referenced by coder_normal(), and coder_passthru().

Variable Documentation

bool try_sparse = true [static]

If true, try to create sparse files when decompressing.

Referenced by io_no_sparse().

int stdout_flags = 0 [static]

File status flags of standard output. This is used by io_open_dest() and io_close_dest().

Referenced by io_close_dest().

/tmp/buildd/xz-utils-5.0.0/src/xz/file_io.c File Reference

Defines

Functions

Variables

Detailed Description

Function Documentation

Variable Documentation