bgpd: Allow 1 prefix to generate statistics

[donaldsharp]

When generating a config with 1 prefix:

BGP IPv4 Unicast RIB statistics
Total Advertisements : 0
Total Prefixes : 0
Average prefix length : 0.00
Unaggregateable prefixes : 0
Maximum aggregateable prefixes: 0
BGP Aggregate advertisements : 0
Address space advertised : 0
% announced : 0.00
/8 equivalent : 0.00
/24 equivalent : 0.00

Advertisements with paths : 0
Longest AS-Path (hops) : 0
Average AS-Path length (hops) : 0.00
Largest AS-Path (bytes) : 0
Average AS-Path size (bytes) : 0.00
Highest public ASN : 0
eva# show bgp ipv4 uni summ
BGP router identifier 10.10.3.11, local AS number 329 vrf-id 0
BGP table version 1
RIB entries 1, using 192 bytes of memory
Peers 1, using 23 KiB of memory

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd PfxSnt
192.168.161.131 4 60000 24 27 0 0 0 00:01:05 (Policy) 1

Total number of neighbors 1

We are not displaying it in the statistics data. This is because FRR is walking the associated
table and comparing the current dest to the top of the tree. I have no idea why this is
the case as that when you have 1 prefix you only have 1 node in your tree. Looking at the
code this is the original code that was imported in 2006. I cannot think of any reason why
FRR needs to exclude this particular node.

Fixed:
eva# show bgp ipv4 uni summ
BGP router identifier 10.10.3.11, local AS number 329 vrf-id 0
BGP table version 1
RIB entries 1, using 192 bytes of memory
Peers 1, using 23 KiB of memory

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd PfxSnt
192.168.161.131 4 60000 24 27 0 0 0 00:01:05 (Policy) 1

Total number of neighbors 1
eva# show bgp ipv4 statistics
BGP IPv4 Unicast RIB statistics (VRF default)
Total Advertisements : 1
Total Prefixes : 1
Average prefix length : 32.00
Unaggregateable prefixes : 1
Maximum aggregateable prefixes: 0
BGP Aggregate advertisements : 0
Address space advertised : 1
% announced : 0.00
/8 equivalent : 0.00
/24 equivalent : 0.00

Advertisements with paths : 1
Longest AS-Path (hops) : 0
Average AS-Path length (hops) : 0.00
Largest AS-Path (bytes) : 0
Average AS-Path size (bytes) : 0.00
Highest public ASN : 0
eva#

Fixes: #7422
Signed-off-by: Donald Sharp [email protected]

[LabN-CI]

💚 Basic BGPD CI results: SUCCESS, 0 tests failed

Results table

_	_
Result	SUCCESS git merge/7447 2b6b4a5
Date	11/03/2020
Start	15:30:53
Finish	15:57:16
Run-Time	26:23
Total	1815
Pass	1815
Fail	0
Valgrind-Errors	0
Valgrind-Loss	0
Details	vncregress-2020-11-03-15:30:53.txt
Log	autoscript-2020-11-03-15:31:54.log.bz2
Memory	473 475 419

For details, please contact louberger

[NetDEF-CI]

Continuous Integration Result: SUCCESSFUL

Congratulations, this patch passed basic tests

Tested-by: NetDEF / OpenSourceRouting.org CI System

CI System Testrun URL: https://ci1.netdef.org/browse/FRR-FRRPULLREQ-15162/

This is a comment from an automated CI system.
For questions and feedback in regards to this CI system, please feel free to email
Martin Winter - mwinter (at) opensourcerouting.org.

Warnings Generated during build:

Debian 10 amd64 build: Successful with additional warnings

Debian Package lintian failed for Debian 10 amd64 build:
(see full package build log at https://ci1.netdef.org/browse/FRR-FRRPULLREQ-15162/artifact/DEB10BUILD/ErrorLog/log_lintian.txt)

W: frr source: pkg-js-tools-test-is-missing
W: frr source: newer-standards-version 4.5.0.3 (current is 4.3.0)
W: frr source: pkg-js-tools-test-is-missing
W: frr source: newer-standards-version 4.5.0.3 (current is 4.3.0)
W: frr-doc: changelog-file-missing-explicit-entry 6.0-2 -> 7.6-dev-20201103-08-g2b6b4a54c-0 (missing) -> 7.6-dev-20201103-08-g2b6b4a54c-0~deb10u1
W: frr-pythontools: changelog-file-missing-explicit-entry 6.0-2 -> 7.6-dev-20201103-08-g2b6b4a54c-0 (missing) -> 7.6-dev-20201103-08-g2b6b4a54c-0~deb10u1
W: frr-rpki-rtrlib: changelog-file-missing-explicit-entry 6.0-2 -> 7.6-dev-20201103-08-g2b6b4a54c-0 (missing) -> 7.6-dev-20201103-08-g2b6b4a54c-0~deb10u1
W: frr-snmp: changelog-file-missing-explicit-entry 6.0-2 -> 7.6-dev-20201103-08-g2b6b4a54c-0 (missing) -> 7.6-dev-20201103-08-g2b6b4a54c-0~deb10u1
W: frr: changelog-file-missing-explicit-entry 6.0-2 -> 7.6-dev-20201103-08-g2b6b4a54c-0 (missing) -> 7.6-dev-20201103-08-g2b6b4a54c-0~deb10u1

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CLANG Static Analyzer Summary

• Github Pull Request 7447, comparing to Git base SHA aeef9fc

No Changes in Static Analysis warnings compared to base

3 Static Analyzer issues remaining.

See details at
https://ci1.netdef.org/browse/FRR-FRRPULLREQ-15162/artifact/shared/static_analysis/index.html