[PATCH 1/3] devfs: add symlink support

[Sascha Hauer]

On Fri, Oct 18, 2013 at 06:33:10PM +0200, Jean-Christophe PLAGNIOL-VILLARD wrote:
> this will allow have symlink for any device such as named partition
> 
> Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
> ---
>  fs/devfs-core.c  | 45 ++++++++++++++++++++++++++++++++++++++++++++-
>  fs/devfs.c       | 42 ++++++++++++++++++++++++++++++++++++++++--
>  include/driver.h |  4 ++++
>  3 files changed, 88 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/devfs-core.c b/fs/devfs-core.c
> index a92d434..0e1ac9a 100644
> --- a/fs/devfs-core.c
> +++ b/fs/devfs-core.c
> @@ -45,13 +45,56 @@ int devfs_partition_complete(struct string_list *sl, char *instr)
>  }
>  #endif
>  
> +struct cdev *devfs_add_symlink_index(const char *filename, struct cdev *src)
> +{
> +	struct cdev *cdev;
> +	int ret;
> +
> +	if (!filename || !src)
> +		return ERR_PTR(-EIO);
> +
> +	ret = cdev_find_free_index(filename);
> +	if (ret == -1)
> +		return ERR_PTR(-ENOMEM);
> +
> +	cdev = xzalloc(sizeof(*cdev));
> +	cdev->name = asprintf("%s%d", filename, ret);
> +	cdev->symlink = src;
> +	ret = devfs_create(cdev);
> +	if (ret)
> +		return ERR_PTR(ret);
> +
> +	return cdev;
> +}
> +
> +struct cdev *devfs_add_symlink(const char *filename, struct cdev *src)
> +{
> +	struct cdev *cdev;
> +	int ret;
> +
> +	if (!filename || !src)
> +		return ERR_PTR(-EIO);
> +
> +	cdev = xzalloc(sizeof(*cdev));
> +	cdev->name = xstrdup(filename);
> +	cdev->symlink = src;

This is not nice.

- You only allow a single symlink
- No check whether this symlink already exists
- calling devfs_remove leaves dangling symlinks behind

Sascha

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |