Re: [PATCH] alsactl: Store lockfile in /tmp

[Jaroslav Kysela <perex@perex.cz>]

Date 6.5.2014 13:57, Julian Scheel wrote:
> It can not be generally assumed that the directories in which asound.state
> resides are writable. Instead using /tmp as location for lock files seems more
> reliable.

Apart the missing free for the mallocated string and ommiting the TMPDIR
environment variable, I think that the right directory for global locks
is /var/lock . The default asound.state directory is now /var/lib/alsa -
I don't see the benefit.

What's the reason for this change? Perhaps using an environmental
variable to override the lock path may be more appropriate for a custom
directory structure.

                                   Jaroslav

> 
> Signed-off-by: Julian Scheel <julian@jusst.de>
> ---
>  alsactl/lock.c | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/alsactl/lock.c b/alsactl/lock.c
> index 587a109..7ca3a09 100644
> --- a/alsactl/lock.c
> +++ b/alsactl/lock.c
> @@ -36,17 +36,24 @@ static int state_lock_(const char *file, int lock, int timeout)
>  	struct flock lck;
>  	struct stat st;
>  	char lcktxt[12];
> +	char *filename;
>  	char *nfile;
>  
>  	if (!do_lock)
>  		return 0;
> -	nfile = malloc(strlen(file) + 6);
> +
> +	/* only use the actual filename, not the path */
> +	filename = strrchr(file, '/');
> +	if (!filename)
> +		filename = file;
> +
> +	nfile = malloc(strlen(filename) + 10);
>  	if (nfile == NULL) {
>  		error("No enough memory...");
>  		return -ENOMEM;
>  	}
> -	strcpy(nfile, file);
> -	strcat(nfile, ".lock");
> +
> +	sprintf(nfile, "/tmp/%s.lock", filename);
>  	lck.l_type = lock ? F_WRLCK : F_UNLCK;
>  	lck.l_whence = SEEK_SET;
>  	lck.l_start = 0;
> 


-- 
Jaroslav Kysela <perex@perex.cz>
Linux Kernel Sound Maintainer
ALSA Project; Red Hat, Inc.