Upgrade Prefix-List & BGP Community-List handling

Affects: lib/plist.c & .h  and bgpd/bgp_clist.c & .h

With very long prefix-lists the repeated scanning of the linked list
of prefix_list_entry slowed things down (scaled O(n**2)).  For lists
of 10,000 or more entries this could consume several *minutes* while
reading a configuration file.

This is a substantial re-working of the code, making use of new
facilities introduced in lib/symtab and lib/vector.

The prefix-list names are held in a symbol table.  The addition of
entries to a prefix-list uses binary-chop searches rather than linear
list scans.

For bgpd, all references to prefix-lists are replaced by symbol table
references.  The peer_prefix_list_update function is called every time
a prefix-list changes.  This used to run through every possible
reference to a prefix-list to see if its address needed updating.

For other daemons, the old interfaces have been preserved.

The prefix match code has been stream-lined a little.

The BGP community-list and extcommunity-list handling has also been
updated to use a symbol table to hold the names.  This improves the
processing of route-maps, which look-up the list by name each time
it is used.  (In the longer term, this should be replaced by the use
of symbol references.)

Other files affected:

  bgpd/bgpd.c & .h
  bgpd/bgp_route.c & .h
  bgpd/bgp_packet.c
  bgpd/bgp_vty.c

    updated to use prefix list references & community list symbols.

  symtab.c & .h

    small change to symbol_dec_ref & symbol_zero_ref to return NULL
    if reference count goes to zero, and the symbol otherwise.

0 files changed, 0 insertions, 0 deletions