tree 99e46a3c95995ff4a23f638ad9bce17f87992391
parent 22630e68279525fd9684c8016f7443a8aba1f2a5
author Neels Hofmeyr <neels@hofmeyr.de> 1589467886 +0200
committer Neels Hofmeyr <neels@hofmeyr.de> 1589802908 +0200

enable vty xml dumping to stdout

Allow dumping the VTY XML reference (for generating manuals) to a normal FILE*
stream instead of a vty output buffer.

We currently generate the VTY reference by starting the client program,
connecting to the VTY telnet and dumping the reference. That is weirdly
convoluted, especially since there has to be a valid config file that
successfully starts up a minimal set of external links before the reference can
be generated. IMO we should have dumped the XML reference to stdout from the
start, and never to a VTY session.

With this patch, it is trivial to generate the XML VTY reference by a
commandline switch. The client program will set up the entire VTY, and
immediately after parsing the cmdline options but before parsing a config file,
just dumps the reference and doesn't even start establishing local ports. That
would allow generating the XML reference on the fly during the build process of
the manuals, without the need of a docker container or somesuch.

A first implementation of such a commandline switch is `osmo-bsc -X`, added in
I316efedb2c1652791434ecf14a1e261367cd2fb7

This patch jumps through a bit of a hoop to still allow dumping to a VTY buffer
without code dup, to still allow dumping the XML reference through telnet VTY,
until all our programs have implemented an -X switch (TM).

Change-Id: Ic74bbdb6dc5ea05f03c791cc70184861e39cd492