From: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Date: Wed, 12 Jan 2022 23:18:08 +0000 (-0500)
Subject: Fix: liblttng-ctl comm: lttng_channel is not packed
X-Git-Tag: v2.13.5~48
X-Git-Url: https://git.liburcu.org/?a=commitdiff_plain;h=714363d38245d57d5fbb657f67bc069d6f4d8aff;hp=714363d38245d57d5fbb657f67bc069d6f4d8aff;p=lttng-tools.git

Fix: liblttng-ctl comm: lttng_channel is not packed

Observed issue
==============

The size of the struct differs between bitness for x86-64 and x86
leading to serialization/deserialization problem across client
(liblttng-ctl) and lttng-sessiond.

sizeof(struct lttng_channel):

  x86: 608
  x86-64: 624

The struct cannot be marked as LTTNG_PACKED since it is part of the API.

Solution
========

Adopt a similar pattern to the new API with a "serialize" &
"create_from_buffer" approach. The only particularity is that we need to
flatten the channels on listing.

Most of the complexity is moved to `src/common/channel.c`

Known drawbacks
=========

None.

Signed-off-by: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: Id5c9aaf3cf8b3d739b71263c02cae8d4d2fedfe3
---