tree 0f4d1897e1b17123a50f7351c74006badbd232da
parent c96e78dde1f118eaee4269aa2c91ef70850e5423
author David Lamparter <equinox@opensourcerouting.org> 1465831752 +0200
committer Paul Jakma <paul@quagga.net> 1485197513 +0000

lib: linklist: add listnode_add_before()

This utility function, to join the zoo that the Quagga linked-list
implementation has accumulated, does an insert-before while returning
the newly allocated node.

It is similar to:
- listnode_add_after(), but
  - complementary direction
  - returns allocated node
- list_add_node_prev(), but
  - supports before == NULL
  - returns allocated node

In general, the entire linked-list implementation is in bad shape, and
while it needs a cleanup / rewrite / replacement, this would both cause
significant conflicts and block other cleanups...

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>