link.c File Reference

Links by path: hard links (link()), symbolic links (symlink(), readlink()), and renaming (rename()). More...

#include <core/system.h>
#include <fs/vfs.h>
#include <aquila/fcntl.h>

Go to the source code of this file.

Functions
int	vfs_link (const char *oldpath, struct uio *ouio, const char *newpath, struct uio *nuio)
	Makes a hard link: a new name for an existing file, in the same mounted filesystem.
int	vfs_symlink (const char *target, const char *path, struct uio *uio)
	Makes a symbolic link.
ssize_t	vfs_readlink (const char *path, struct uio *uio, char *buf, size_t size)
	Reads what a symbolic link contains.
static int	entry_get (struct vnode *dir, const char *name, struct vnode **ref)
	Gets the vnode of the entry name of dir, or NULL in *ref if there is none.
int	vfs_rename (const char *oldpath, struct uio *ouio, const char *newpath, struct uio *nuio)
	Renames a file or a directory, possibly to another directory of the same mounted filesystem.

Detailed Description

Links by path: hard links (link()), symbolic links (symlink(), readlink()), and renaming (rename()).

Definition in file link.c.

Function Documentation

entry_get()

int entry_get ( struct vnode * dir, const char * name, struct vnode ** ref )

static

Gets the vnode of the entry name of dir, or NULL in *ref if there is none.

Returns 0 or a negative errno.

Definition at line 127 of file link.c.

References entry_get(), NULL, vfs_finddir(), and vfs_vget().

Referenced by entry_get(), and vfs_rename().

vfs_link()

int vfs_link	(	const char *	oldpath,
		struct uio *	ouio,
		const char *	newpath,
		struct uio *	nuio )

Makes a hard link: a new name for an existing file, in the same mounted filesystem.

Directories can't be linked.

Parameters

oldpath	the file's path, followed if it's a symbolic link unless ouio has O_NOFOLLOW
ouio	who is asking, and the directory oldpath is relative to
newpath	the new name's path
nuio	who is asking, and the directory newpath is relative to

Returns

0, -EPERM for a directory, -EEXIST, -EXDEV across filesystems, or another negative errno

Definition at line 24 of file link.c.

References kfree(), vnode::mode, NULL, vfs_access(), vfs_close(), vfs_link(), vfs_lookup_dir(), vfs_lookup_parent(), vfs_mount_root_of(), vfs_vlink(), VFS_W, and VFS_X.

Referenced by do_linkat(), and vfs_link().

vfs_readlink()

ssize_t vfs_readlink	(	const char *	path,
		struct uio *	uio,
		char *	buf,
		size_t	size )

Reads what a symbolic link contains.

Parameters

path	the link's path (not followed)
uio	who is asking
buf	where the contents go, not NUL-terminated
size	the buffer's size

Returns

the number of bytes read, -EINVAL if path isn't a symbolic link, or a negative errno

Definition at line 105 of file link.c.

References uio::flags, MIN, vnode::mode, NULL, vnode::size, vfs_close(), vfs_lookup(), vfs_read(), and vfs_readlink().

Referenced by creat_path(), sys_readlinkat(), and vfs_readlink().

vfs_rename()

int vfs_rename	(	const char *	oldpath,
		struct uio *	ouio,
		const char *	newpath,
		struct uio *	nuio )

Renames a file or a directory, possibly to another directory of the same mounted filesystem.

An entry at the new name is replaced: a file by a file, or an empty directory by a directory.

Parameters

oldpath	the path it has
ouio	who is asking, and the directory oldpath is relative to
newpath	the path it gets
nuio	the directory newpath is relative to

Returns

0, -ENOENT, -EXDEV, -EINVAL to move a directory into itself, -ENOTDIR, -EISDIR, -ENOTEMPTY, or another negative errno

Definition at line 154 of file link.c.

References entry_get(), kfree(), NULL, vfs_access(), vfs_close(), vfs_dir_empty(), vfs_lookup_parent(), vfs_mount_root_of(), vfs_rename(), vfs_under(), vfs_vrename(), VFS_W, and VFS_X.

Referenced by sys_renameat(), and vfs_rename().

vfs_symlink()

int vfs_symlink	(	const char *	target,
		const char *	path,
		struct uio *	uio )

Makes a symbolic link.

Parameters

target	what the link contains (not checked: it may not exist)
path	the link's path
uio	who is asking

Returns

0, -ENOENT for an empty target, or a negative errno

Definition at line 72 of file link.c.

References NULL, vfs_close(), vfs_mknod(), vfs_symlink(), vfs_unlink(), and vfs_write().

Referenced by sys_symlinkat(), and vfs_symlink().