From: Stefan Sperling <stsp@stsp.name>
Subject: Re: make got_pack_create write to a file descriptor
To: Omar Polo <op@omarpolo.com>
Cc: gameoftrees@openbsd.org
Date: Sat, 15 Oct 2022 20:28:18 +0200

On Sat, Oct 15, 2022 at 07:47:05PM +0200, Omar Polo wrote:
> > The old code required a seekable output file. This conflicts with requirements
> > of future gotd(8), which will write pack file data to network sockets.
> 
> should we need to worry about possible partial writes in hwrite then?

This data will be written to an AF_UNIX socket, and we write it
in blocking i/o mode. As explained on IRC, the process creating
the pack file is not the main gotd parent process, but a repo_read
helper process which can block without causing issues.

Git-protocol pkt-line framing happens in gotsh(1), which will receive
the pack-file data on its socket and either stream it to its stdout
directly, or, if the client supports sidebands (most clients, including
'got fetch', do support this), gotsh(1) will chunk the pack-file data
into pkt-lines on the packfile data sideband.