5.6 KiB
lws release policy
How should users consume lws?
The one definitively wrong way to consume lws (or anything else) is "import" some version of it into your proprietary tree and think you will stick with that forever, perhaps piling cryptic fixes or hacks on top until quite quickly, nobody dare think about updating it.
The stable releases go on to a branch like v4.0-stable as described below, over time these attract dozens or even hundreds of minor or major fix patches backported from master. So you should not consume tags like v4.0.0 but build into your planning that you will need to follow v4.0-stable in order to stay on top of known bugs.
And we only backport fixes to the last stable release, although we will make exceptions for important fixes. So after a while, trying to stick with one old versions means nobody is providing security fixes on it any more. So you should build into your planning that you will follow lws release upgrades.
If you find problems and create fixes, please upstream them, simplifying your life so you can just directly consume the upstream tree with no private changes.
Master branch
Master branch is the default and all new work happens there. It's unstable and subject to history rewrites, patches moving about and being squashed etc. In terms of it working, it is subject to passing CI tests including a battery of runtime tests, so if it is passing CI as it usually is then it's probably in usable shape. See "Why no history on master" below for why it's managed like that.
If you have patches (you are a hero) they should be targeted at master.
To follow such a branch, git pull is the wrong tool... the starting point
of what you currently have may no longer exist remotely due to rearranging the
patches there. Instead use a flow like this:
$ git fetch https://libwebsockets.org/repo/libwebsockets +master:m && git reset --hard m
This fetches current remote master into local branch m, and then forces your
local checkout to exactly match m. This replaces your checked-out tree
including any of your local changes, so stash those first, or use stgit or so
to pop them before updating your basis against lws master.
Stable branches
Master is very useful for coordinating development, and integrating WIP, but for distros or integration into large user projects some stability is often more desirable than the latest development work.
Periodically, when master seems in good shape and various new developments seem
to be working, it's copied out into a versioned stable branch, like v3.0-stable.
The initial copy is tagged with, eg, v3.0.0.
(At that time, master's logical version is set to "...99", eg, v3.0.99 so
version comparisons show that version of master is "later" than any other
v3.0 version, which will never reach 99 point releases itself, but "earlier"
than, eg, v3.1.)
Backport policy
Work continues on master, and as part of that usually bugs are reported and / or fixes found that may apply not just to current master, but the version of master that was copied to form the last -stable branch.
In that case, the patch may be backported to the last stable branch to also fix the bug there. In the case of refactors or major internal improvements, these typically do not get backported.
This applies only to fixes and public API-neutral internal changes to lws... if new features were backported or API changes allowed, then there would be multiple apis under the same version name and library soname, which is madness.
When new stable releases are made, the soname is bumped reflecting the API is different than that of previous versions.
If there is something you need in a later lws version that is not backported, you need to either backport it yourself or use a later lws version. Using a more recent version of lws (and contributing fixes and changes so you yourself can get them easily as well as contributing for others) is almost always the correct way.
Stable point releases
Periodically fix patches pile up on the -stable branch and are tagged out as "point releases". So if the original stable release was "v3.0.0", the point release may be "v3.0.1".
Critical fixes
Sometimes a bug is found and fixed that had been hiding for a few versions. If the bug has some security dimension or is otherwise important, we may backport it to a few recent releases, not just the last one. This is pretty uncommon though.
Why no history on master
Git is a wonderful tool that can be understood to have two main modes of operation, merge and rebase that are mutually exclusive. Most devs only use merge / pull, but rebase / fetch is much more flexible. Running master via rebases allows me to dispense with feature branches during development and enables tracking multiple in-progress patches in-tree by updating them in place. If this doesn't make sense or seems heretical to you, it's OK I don't need devsplain'ing about it, just sit back and enjoy the clean, rapid development results.
Since stable branches don't allow new features, they are run as traditional trees with a history, like a one-way pile of patches on top of the original release. If CI shows something is messed up with the latest patch, I will edit it in-place if it has only been out for a few hours, but there is no re-ordering or other history manipulation.