Add configure option to disable pthreads support
Remove unreachable code

This code gets never called anyway
Add missing va_end() calls

Add missing va_end() calls on all error paths
Set err and free ntbl when leaving neightbl_msg_parser

Make sure we leave neightbl_msg_parser() by setting the proper err variable and
freeing ntbl
Add new object op oo_id_attrs_get

The current oo_id_attrs nl_object op allows a fixed
id attribute list for an cache. But a cache with multiple families
may need to specify different id attributes for different families.

An example for this is the bridge fdb entries in the neigh cache:
neigh entries belonging to the AF_UNSPEC family use
(NEIGH_ATTR_IFINDEX | NEIGH_ATTR_DST | NEIGH_ATTR_FAMILY) as id attributes.
AF_BRIDGE fdb entries which also support the same msg type, will need to use
(NEIGH_ATTR_LLADDR | NEIGH_ATTR_FAMILY) as id attributes.
Today you cannot specify different set of attributes to two families belonging
to the same cache.

This patch adds a new object function oo_id_attrs_get to get the attributes.
An example implementation of oo_id_attrs_get for the neigh cache will
look like:
static uint32_t neigh_id_attrs_get(struct nl_object *obj)
{
        struct rtnl_neigh *neigh = (struct rtnl_neigh *)obj;

        if (neigh->n_family == AF_BRIDGE)
                return (NEIGH_ATTR_LLADDR | NEIGH_ATTR_FAMILY);
        else
                return (NEIGH_ATTR_IFINDEX | NEIGH_ATTR_DST | NEIGH_ATTR_FAMILY);
}

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: Nolan Leake <nolan@cumulusnetworks.com>
Reviewed-by: Shrijeet Mukherjee <shm@cumulusnetworks.com>
Reviewed-by: Wilson Kok <wkok@cumulusnetworks.com>
Add support for updating objects in the cache

This patch adds support to update a cache object during cache_include instead
of the current approach of deleting the original object and adding a new one.
This operation is conditional on the object implementing the operation. If
the update is not successful, cache_include falls back to the existing cache
inclusion process of deleting and adding the object.

It adds a new object operation called oo_update. oo_update takes two objects
as arguments, first being the existing cache object that needs update, the
second argument being the new object. Currently it is left to the implementor
to use the msg type to decide wether to delete or add the new object attributes
to the old one. But the operation type or msg type can be easily made part of the
object arguments.

The motivation for this change is explained below in the context of including
support for AF_BRIDGE objects into the link cache.

libnl today deletes an object before it includes an identical object.
But for some objects like the AF_BRIDGE objects this does not work well.
link cache uses the ifindex as its key in object searches.
If link cache were to support AF_BRIDGE family objects, todays implementation,
	- will replace the original link object with the bridge port link object
	  for add notifications
	- And a bridge port delete notification from kernel would delete the
	link object from the cache leaving the cache without the link object
	until the kernel sends another notification for that link

The bridge port link notification contains some base link object attributes
plus bridge specific protocol info attributes. In such cases we think an
operation to update the existing object in place in cache might be useful.

This can be made to work for AF_INET6 link objects too.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: Nolan Leake <nolan@cumulusnetworks.com>
Reviewed-by: Shrijeet Mukherjee <shm@cumulusnetworks.com>
Reviewed-by: Wilson Kok <wkok@cumulusnetworks.com>
Document buffer size limitations of nl_recv()
nl_recv: Don't update *buf in error path

iov.iov_base is either NULL or invalid
nl_recv: improve function documentation
nl_recv: return NLE_INVAL if buf is NULL
nl_recv: return NLE_INVAL if socket address pointer is NULL
nl_recv: fix indent style
socket: document nl_socket_get_fd()
nl: improve nl_sendto() docs and error checks

Make nl_sendto() return NLE_INVAL if provided buffer is NULL
and make it return NLE_BAD_SOCK if the socket is not connected.

Add note in docs about lack of NL_CB_MSG_OUT invokation
doc: increase dot max graph nodes to 100
nl: improve API doc of transmit functions

Signed-off-by: Thomas Graf <tgraf@redhat.com>
nl: Allow to overwrite nl_send()

Up to now only calls to nl_send_auto() could be overwritten with
nl_cb_overwrite_send(). This patch extends the capability to
nl_send()

Signed-off-by: Thomas Graf <tgraf@redhat.com>
nl: Improve API doc of nl_connect() and nl_close()

Signed-off-by: Thomas Graf <tgraf@redhat.com>
nl: Improve API doc of nl_send_simple()

Signed-off-by: Thomas Graf <tgraf@redhat.com>
Add hash function

This patch adds a hash function for hashing libnl objects.

This hash function is from:
http://ccodearchive.net/info/hash.html

The original code was modified to remove unwanted dependencies,
unwanted code and fixes to header file locations

One requirement with this hash function is, hashing over multiple fields of an
un-packed struct requires that the struct be zeroed, otherwise random padding
bytes will change the hash.

Signed-off-by: Shrijeet Mukherjee <shm@cumulusnetworks.com>
Signed-off-by: Nolan Leake <nolan@cumulusnetworks.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: Wilson Kok <wkok@cumulusnetworks.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>