PERFORCE change 119444 for review

[Julian Elischer]

Marko Zec wrote:
> http://perforce.freebsd.org/chv.cgi?CH=119444
> 
> Change 119444 by zec at zec_tpx32 on 2007/05/07 22:51:07
> 
> 	Add support for free-floating ng_hub and ng_bridge instances.
> 	
> 	If a hook named "anchor" is created on a ng_hub or ng_bridge
> 	node instance, the node will not self-destruct even if it
> 	has no hooks connected.  Reminder: normal behavior is that
> 	hub or bridge nodes automatically destroy themselves when
> 	the last hook is disconnected.

What is this hook attached to?
One could just as easily send them a 'become persistant' message..
It would be a good candidate for a generic message.
Data is still sent to this hook. is that what is expected?


> 
> Affected files ...
> 
> .. //depot/projects/vimage/src/sys/netgraph/ng_bridge.c#2 edit
> .. //depot/projects/vimage/src/sys/netgraph/ng_hub.c#2 edit
> 
> Differences ...
> 
> ==== //depot/projects/vimage/src/sys/netgraph/ng_bridge.c#2 (text+ko) ====
> 
> @@ -95,13 +95,14 @@
>  /* Per-node private data */
>  struct ng_bridge_private {
>  	struct ng_bridge_bucket	*tab;		/* hash table bucket array */
> -	struct ng_bridge_link	*links[NG_BRIDGE_MAX_LINKS];
> +	struct ng_bridge_link	*links[NG_BRIDGE_MAX_LINKS + 1];
>  	struct ng_bridge_config	conf;		/* node configuration */
>  	node_p			node;		/* netgraph node */
>  	u_int			numHosts;	/* num entries in table */
>  	u_int			numBuckets;	/* num buckets in table */
>  	u_int			hashMask;	/* numBuckets - 1 */
>  	int			numLinks;	/* num connected links */
> +	int			persistent;	/* can exist w/o any hooks */
>  	struct callout		timer;		/* one second periodic timer */
>  };
>  typedef struct ng_bridge_private *priv_p;
> @@ -342,13 +343,13 @@
>  ng_bridge_newhook(node_p node, hook_p hook, const char *name)
>  {
>  	const priv_p priv = NG_NODE_PRIVATE(node);
> +	int linkNum = -1;
>  
>  	/* Check for a link hook */
>  	if (strncmp(name, NG_BRIDGE_HOOK_LINK_PREFIX,
>  	    strlen(NG_BRIDGE_HOOK_LINK_PREFIX)) == 0) {
>  		const char *cp;
>  		char *eptr;
> -		u_long linkNum;
>  
>  		cp = name + strlen(NG_BRIDGE_HOOK_LINK_PREFIX);
>  		if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
> @@ -356,6 +357,14 @@
>  		linkNum = strtoul(cp, &eptr, 10);
>  		if (*eptr != '\0' || linkNum >= NG_BRIDGE_MAX_LINKS)
>  			return (EINVAL);
> +	} else if (strcmp(name, "anchor") == 0) {
> +		linkNum = NG_BRIDGE_MAX_LINKS;
> +		if (priv->persistent)
> +			return (EISCONN);
> +		priv->persistent = 1;
> +	}
> +
> +	if (linkNum >= 0 ) {
>  		if (priv->links[linkNum] != NULL)
>  			return (EISCONN);
>  		MALLOC(priv->links[linkNum], struct ng_bridge_link *,
> @@ -366,7 +375,7 @@
>  		NG_HOOK_SET_PRIVATE(hook, (void *)linkNum);
>  		priv->numLinks++;
>  		return (0);
> -	}
> +        }
>  
>  	/* Unknown hook name */
>  	return (EINVAL);
> @@ -796,7 +805,8 @@
>  
>  	/* If no more hooks, go away */
>  	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
> -	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) {
> +	    && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))
> +	    && !priv->persistent) {
>  		ng_rmnode_self(NG_HOOK_NODE(hook));
>  	}
>  	return (0);
> 
> ==== //depot/projects/vimage/src/sys/netgraph/ng_hub.c#2 (text+ko) ====
> 
> @@ -37,6 +37,7 @@
>  #include <netgraph/netgraph.h>
>  
>  static ng_constructor_t	ng_hub_constructor;
> +static ng_newhook_t	ng_hub_newhook;
>  static ng_rcvdata_t	ng_hub_rcvdata;
>  static ng_disconnect_t	ng_hub_disconnect;
>  
> @@ -44,6 +45,7 @@
>  	.version =	NG_ABI_VERSION,
>  	.name =		NG_HUB_NODE_TYPE,
>  	.constructor =	ng_hub_constructor,
> +	.newhook =	ng_hub_newhook,
>  	.rcvdata =	ng_hub_rcvdata,
>  	.disconnect =	ng_hub_disconnect,
>  };
> @@ -57,6 +59,14 @@
>  	return (0);
>  }
>  
> +static  int
> +ng_hub_newhook(node_p node, hook_p hook, const char *name)
> +{
> +        if (strcmp(name, "anchor") == 0)
> +                node->nd_private = (void *) 1;
> +        return 0;
> +}
> +
>  static int
>  ng_hub_rcvdata(hook_p hook, item_p item)
>  {
> @@ -94,7 +104,7 @@
>  {
>  
>  	if (NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0 &&
> -	    NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))
> +	    NG_NODE_IS_VALID(NG_HOOK_NODE(hook)) && !hook->hk_node->nd_private)
>  		ng_rmnode_self(NG_HOOK_NODE(hook));
>  	return (0);
>  }