Wrappers for low-level POSIX I/O routines. More...

#include <sys/types.h>
#include "safefcntl.h"
#include "safeunistd.h"
#include <string>

Include dependency graph for io_utils.h:

This graph shows which files directly or indirectly include this file:

Functions
int	io_open_block_rd (const char *fname)
	Open a block-based file for reading. More...

int	io_open_block_rd (const std::string &fname)
	Open a block-based file for reading. More...

int	io_open_block_wr (const char *fname, bool anew)
	Open a block-based file for writing. More...

int	io_open_block_wr (const std::string &fname, bool anew)
	Open a block-based file for writing. More...

bool	io_sync (int fd)
	Ensure all data previously written to file descriptor fd has been written to disk. More...

bool	io_full_sync (int fd)

size_t	io_read (int fd, char *p, size_t n, size_t min=0)
	Read n bytes (or until EOF) into block pointed to by p from file descriptor fd. More...

void	io_write (int fd, const char *p, size_t n)
	Write n bytes from block pointed to by p to file descriptor fd. More...

void	io_write (int fd, const unsigned char *p, size_t n)

bool	io_readahead_block (int, size_t, off_t, off_t=0)
	Readahead block b size n bytes from file descriptor fd. More...

void	io_read_block (int fd, char *p, size_t n, off_t b, off_t o=0)
	Read block b size n bytes into buffer p from file descriptor fd, offset o. More...

void	io_write_block (int fd, const char *p, size_t n, off_t b, off_t o=0)
	Write block b size n bytes from buffer p to file descriptor fd, offset o. More...

void	io_write_block (int fd, const unsigned char *p, size_t n, off_t b)

bool	io_unlink (const std::string &filename)
	Delete a file. More...

bool	io_tmp_rename (const std::string &tmp_file, const std::string &real_file)
	Rename a temporary file to its final position. More...

Detailed Description

Wrappers for low-level POSIX I/O routines.

Definition in file io_utils.h.

Function Documentation

◆ io_full_sync()

bool io_full_sync ( int fd )

inline

Definition at line 88 of file io_utils.h.

References io_read(), io_sync(), and io_write().

Referenced by ChertTable::commit(), GlassVersion::sync(), and test_ioblock1().

◆ io_open_block_rd() [1/2]

int io_open_block_rd ( const char * fname )

inline

Open a block-based file for reading.

Parameters

fname The path of the file to open.

Definition at line 38 of file io_utils.h.

References O_BINARY, O_CLOEXEC, and Xapian::InMemory::open().

Referenced by GlassTable::do_open_to_read(), ChertTable::do_open_to_read(), io_open_block_rd(), and test_ioblock1().

◆ io_open_block_rd() [2/2]

int io_open_block_rd ( const std::string & fname )

inline

Open a block-based file for reading.

Parameters

fname The path of the file to open.

Definition at line 46 of file io_utils.h.

References io_open_block_rd(), and io_open_block_wr().

◆ io_open_block_wr() [1/2]

int io_open_block_wr	(	const char *	fname,
		bool	anew
	)

Open a block-based file for writing.

Parameters

fname	The path of the file to open.
anew	If true, open the file anew (create or truncate it).

Definition at line 67 of file io_utils.cc.

References Assert, close(), MIN_WRITE_FD, O_BINARY, O_CLOEXEC, and Xapian::InMemory::open().

Referenced by GlassTable::do_open_to_write(), ChertTable::do_open_to_write(), io_open_block_rd(), io_open_block_wr(), and test_ioblock1().

◆ io_open_block_wr() [2/2]

int io_open_block_wr	(	const std::string &	fname,
		bool	anew
	)

inline

Open a block-based file for writing.

Parameters

fname	The path of the file to open.
anew	If true, open the file anew (create or truncate it).

Definition at line 63 of file io_utils.h.

References io_open_block_wr().

◆ io_read()

size_t io_read	(	int	fd,
		char *	p,
		size_t	n,
		size_t	min = `0`
	)

Read n bytes (or until EOF) into block pointed to by p from file descriptor fd.

If a read error occurs, throws DatabaseError.

If min is specified and EOF is reached after less than min bytes, throws DatabaseCorruptError.

Returns the number of bytes actually read.

Definition at line 123 of file io_utils.cc.

Referenced by ChertTableCheck::check(), GlassChanges::check(), GlassDatabase::get_changeset_revisions(), ChertDatabase::get_changeset_revisions(), io_full_sync(), ChertTable_base::read(), GlassVersion::read(), ChertVersion::read_and_check(), and test_if_single_file_db().

◆ io_read_block()

void io_read_block	(	int	fd,
		char *	p,
		size_t	n,
		off_t	b,
		off_t	o = `0`
	)

Read block b size n bytes into buffer p from file descriptor fd, offset o.

Definition at line 180 of file io_utils.cc.

References rare, throw_block_error(), and usual.

Referenced by io_readahead_block(), ChertTable::read_block(), GlassTable::read_block(), and test_ioblock1().

◆ io_readahead_block()

bool io_readahead_block	(	int	,
		size_t	,
		off_t	,
		off_t	= `0`
	)

inline

Readahead block b size n bytes from file descriptor fd.

Returns false if we can't readahead on this fd.

Definition at line 133 of file io_utils.h.

References io_read_block(), and io_write_block().

Referenced by io_write(), ChertTable::readahead_key(), GlassTable::readahead_key(), test_ioblock1(), and throw_block_error().

◆ io_sync()

bool io_sync ( int fd )

inline

Ensure all data previously written to file descriptor fd has been written to disk.

Returns false if this could not be done.

Definition at line 73 of file io_utils.h.

Referenced by GlassDatabaseReplicator::commit(), GlassChanges::commit(), ChertTable::commit(), ChertVersion::create(), io_full_sync(), ChertDatabaseReplicator::process_changeset_chunk_base(), ChertDatabaseReplicator::process_changeset_chunk_blocks(), GlassDatabaseReplicator::process_changeset_chunk_version(), GlassVersion::sync(), GlassTable::sync(), test_ioblock1(), and ChertTable_base::write_to_file().

◆ io_tmp_rename()

bool io_tmp_rename	(	const std::string &	tmp_file,
		const std::string &	real_file
	)

Rename a temporary file to its final position.

Attempts to deal with NFS infelicities. If the rename fails, the temporary file is removed.

Returns: true if the rename succeeded; false if it failed (and errno will be set appropriately).

Definition at line 271 of file io_utils.cc.

References posixy_rename.

Referenced by GlassChanges::commit(), ChertTable::commit(), Xapian::Database::compact_(), io_write_block(), ChertDatabaseReplicator::process_changeset_chunk_base(), GlassDatabaseReplicator::process_changeset_chunk_version(), GlassVersion::sync(), and Xapian::DatabaseReplica::Internal::update_stub_database().

◆ io_unlink()

bool io_unlink ( const std::string & filename )

Delete a file.

Parameters

filename The file to delete.

Exceptions

Xapian::DatabaseError is thrown if filename existed but couldn't be unlinked.

Returns: true if filename was successfully removed; false if it didn't exist. If the file is on NFS, false may be returned even if the file was removed (if the server fails after removing the file but before telling the client, and the client then retries).

Definition at line 52 of file io_utils.cc.

References posixy_unlink.

Referenced by GlassChanges::commit(), ChertTable::create_and_open(), GlassTable::create_and_open(), ChertTable::erase(), io_write_block(), ChertDatabase::set_revision_number(), test_ioblock1(), ChertTable::write_block(), and GlassChanges::~GlassChanges().