L4Re::Vfs::Regular_file Class Reference

Interface for a POSIX file that provides regular file semantics. More...

#include <vfs.h>

Inheritance diagram for L4Re::Vfs::Regular_file:

Collaboration diagram for L4Re::Vfs::Regular_file:

Public Member Functions
virtual L4::Cap< L4Re::Dataspace >	data_space () noexcept=0
	Get an L4Re::Dataspace object for the file.
virtual ssize_t	readv (const struct iovec *, int iovcnt) noexcept=0
	Read one or more blocks of data from the file.
virtual ssize_t	writev (const struct iovec *, int iovcnt) noexcept=0
	Write one or more blocks of data to the file.
virtual off64_t	lseek64 (off64_t, int) noexcept=0
	Change the file pointer.
virtual int	ftruncate64 (off64_t pos) noexcept=0
	Truncate the file at the given position.
virtual int	fsync () const noexcept=0
	Sync the data and meta data to persistent storage.
virtual int	fdatasync () const noexcept=0
	Sync the data to persistent storage.
virtual int	get_lock (struct flock64 *lock) noexcept=0
	Test if the given lock can be placed in the file.
virtual int	set_lock (struct flock64 *lock, bool wait) noexcept=0
	Acquire or release the given lock on the file.

Detailed Description

Interface for a POSIX file that provides regular file semantics.

Real objects always use the combined L4Re::Vfs::File interface.

Definition at line 267 of file vfs.h.

Member Function Documentation

data_space()

virtual L4::Cap< L4Re::Dataspace > L4Re::Vfs::Regular_file::data_space ( )

pure virtualnoexcept

Get an L4Re::Dataspace object for the file.

This is used as a backend for POSIX mmap and mmap2 functions.

Note

mmap is not possible if the function returns an invalid capability.

Returns

A capability to an L4Re::Dataspace that represents the file contents in an L4Re way.

Implemented in L4Re::Vfs::Be_file.

fdatasync()

virtual int L4Re::Vfs::Regular_file::fdatasync ( ) const

pure virtualnoexcept

Sync the data to persistent storage.

This is the backend for POSIX fdatasync.

Implemented in L4Re::Vfs::Be_file.

fsync()

virtual int L4Re::Vfs::Regular_file::fsync ( ) const

pure virtualnoexcept

Sync the data and meta data to persistent storage.

This is the backend for POSIX fsync.

Implemented in L4Re::Vfs::Be_file.

ftruncate64()

virtual int L4Re::Vfs::Regular_file::ftruncate64 ( off64_t  pos )

pure virtualnoexcept

Truncate the file at the given position.

This function is the backend for truncate and friends.

Parameters

pos	The offset at which the file shall be truncated.

Returns

0 on success, or <0 on error.

Implemented in L4Re::Vfs::Be_file.

get_lock()

virtual int L4Re::Vfs::Regular_file::get_lock ( struct flock64 *  lock )

pure virtualnoexcept

Test if the given lock can be placed in the file.

This function is used as backend for fcntl F_GETLK commands.

Parameters

lock	The lock that shall be placed on the file. The l_type member will contain F_UNLCK if the lock could be placed.

Returns

0 on success, <0 on error.

Implemented in L4Re::Vfs::Be_file.

lseek64()

virtual off64_t L4Re::Vfs::Regular_file::lseek64 ( off64_t  , int    )

pure virtualnoexcept

Change the file pointer.

This is the backend for POSIX seek, lseek and friends.

Returns

The new file position, or <0 on error.

Implemented in L4Re::Vfs::Be_file.

readv()

virtual ssize_t L4Re::Vfs::Regular_file::readv ( const struct iovec *  , int  iovcnt  )

pure virtualnoexcept

Read one or more blocks of data from the file.

This function acts as backend for POSIX read and readv calls and reads data starting from the f_pos pointer of that open file. The file pointer is advanced according to the number of bytes read.

Returns

The number of bytes read from the file, or <0 on error.

Implemented in L4Re::Vfs::Be_file.

set_lock()

virtual int L4Re::Vfs::Regular_file::set_lock ( struct flock64 *  lock, bool  wait  )

pure virtualnoexcept

Acquire or release the given lock on the file.

This function is used as backend for fcntl F_SETLK and F_SETLKW commands.

Parameters

lock	The lock that shall be placed on the file.
wait	If true, then block if there is a conflicting lock on the file.

Returns

0 on success, <0 on error.

Implemented in L4Re::Vfs::Be_file.

writev()

virtual ssize_t L4Re::Vfs::Regular_file::writev ( const struct iovec *  , int  iovcnt  )

pure virtualnoexcept

Write one or more blocks of data to the file.

This function acts as backend for POSIX write and writev calls. The data is written starting at the current file pointer and the file pointer must be advanced according to the number of written bytes.

Returns

The number of bytes written to the file, or <0 on error.

Implemented in L4Re::Vfs::Be_file.

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

• l4/l4re_vfs/vfs.h