[lxc-devel] [PATCH 2/3] Factor out capability parsing logic

[Serge Hallyn]

Quoting Christian Seiler (christian at iwakd.de):
> Currently, setup_caps and dropcaps_except both use the same parsing
> logic for parsing capabilities (try to identify by name, but allow
> numerical specification). Since this is a common routine, separate it
> out to improve maintainability and reuseability.
> 
> Signed-off-by: Christian Seiler <christian at iwakd.de>

Acked-by: Serge E. Hallyn <serge.hallyn at ubuntu.com>

> ---
>  src/lxc/conf.c |   88 ++++++++++++++++++++++----------------------------------
>  1 file changed, 35 insertions(+), 53 deletions(-)
> 
> diff --git a/src/lxc/conf.c b/src/lxc/conf.c
> index d765f0d..716fcad 100644
> --- a/src/lxc/conf.c
> +++ b/src/lxc/conf.c
> @@ -2160,42 +2160,49 @@ static int setup_mount_entries(const struct lxc_rootfs *rootfs, struct lxc_list
>  	return ret;
>  }
>  
> +static int parse_cap(const char *cap)
> +{
> +	char *ptr = NULL;
> +	int i, capid = -1;
> +
> +	for (i = 0; i < sizeof(caps_opt)/sizeof(caps_opt[0]); i++) {
> +
> +		if (strcmp(cap, caps_opt[i].name))
> +			continue;
> +
> +		capid = caps_opt[i].value;
> +		break;
> +	}
> +
> +	if (capid < 0) {
> +		/* try to see if it's numeric, so the user may specify
> +		 * capabilities  that the running kernel knows about but
> +		 * we don't */
> +		errno = 0;
> +		capid = strtol(cap, &ptr, 10);
> +		if (!ptr || *ptr != '\0' || errno != 0)
> +			/* not a valid number */
> +			capid = -1;
> +		else if (capid > lxc_caps_last_cap())
> +			/* we have a number but it's not a valid
> +			 * capability */
> +			capid = -1;
> +	}
> +
> +	return capid;
> +}
> +
>  static int setup_caps(struct lxc_list *caps)
>  {
>  	struct lxc_list *iterator;
>  	char *drop_entry;
> -	char *ptr;
> -	int i, capid;
> +	int capid;
>  
>  	lxc_list_for_each(iterator, caps) {
>  
>  		drop_entry = iterator->elem;
>  
> -		capid = -1;
> -
> -		for (i = 0; i < sizeof(caps_opt)/sizeof(caps_opt[0]); i++) {
> -
> -			if (strcmp(drop_entry, caps_opt[i].name))
> -				continue;
> -
> -			capid = caps_opt[i].value;
> -			break;
> -		}
> -
> -		if (capid < 0) {
> -			/* try to see if it's numeric, so the user may specify
> -			* capabilities  that the running kernel knows about but
> -			* we don't */
> -			errno = 0;
> -			capid = strtol(drop_entry, &ptr, 10);
> -			if (!ptr || *ptr != '\0' || errno != 0)
> -				/* not a valid number */
> -				capid = -1;
> -			else if (capid > lxc_caps_last_cap())
> -				/* we have a number but it's not a valid
> -				* capability */
> -				capid = -1;
> -		}
> +		capid = parse_cap(drop_entry);
>  
>  	        if (capid < 0) {
>  			ERROR("unknown capability %s", drop_entry);
> @@ -2220,7 +2227,6 @@ static int dropcaps_except(struct lxc_list *caps)
>  {
>  	struct lxc_list *iterator;
>  	char *keep_entry;
> -	char *ptr;
>  	int i, capid;
>  	int numcaps = lxc_caps_last_cap() + 1;
>  	INFO("found %d capabilities", numcaps);
> @@ -2236,31 +2242,7 @@ static int dropcaps_except(struct lxc_list *caps)
>  
>  		keep_entry = iterator->elem;
>  
> -		capid = -1;
> -
> -		for (i = 0; i < sizeof(caps_opt)/sizeof(caps_opt[0]); i++) {
> -
> -			if (strcmp(keep_entry, caps_opt[i].name))
> -				continue;
> -
> -			capid = caps_opt[i].value;
> -			break;
> -		}
> -
> -		if (capid < 0) {
> -			/* try to see if it's numeric, so the user may specify
> -			* capabilities  that the running kernel knows about but
> -			* we don't */
> -			capid = strtol(keep_entry, &ptr, 10);
> -			if (!ptr || *ptr != '\0' ||
> -			capid == INT_MIN || capid == INT_MAX)
> -				/* not a valid number */
> -				capid = -1;
> -			else if (capid > lxc_caps_last_cap())
> -				/* we have a number but it's not a valid
> -				* capability */
> -				capid = -1;
> -		}
> +		capid = parse_cap(keep_entry);
>  
>  	        if (capid < 0) {
>  			ERROR("unknown capability %s", keep_entry);
> -- 
> 1.7.10.4
> 
> _______________________________________________
> lxc-devel mailing list
> lxc-devel at lists.linuxcontainers.org
> http://lists.linuxcontainers.org/listinfo/lxc-devel