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90 lines
3.2 KiB
Markdown
90 lines
3.2 KiB
Markdown
# About
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This directory contains the source code for a tiny init devised for
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the Pygos system.
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The main goal of this project is to create a simple framework for:
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- system boot up and initialization
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- service supervision
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With the additional aims of having something that:
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- simply works
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- is easy to understand
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- is easy to configure and maintain
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The init process is intended to run on top of Linux and makes use of some
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Linux specific features (e.g. signalfd), but if sufficient interest exists,
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it should still be possible to make it run on some BSDs or whatever else.
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The init system tries to mimic the concept of unit files from systemd as those
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were considered to be a good design choice.
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Those parameterizeable service description files are stored in `/usr/share/init`
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by default. Services are enabled by creating a symlink in `/etc/init.d`. This
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can be done using the `service` command line tool.
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See [docs/services.md](docs/services.md) for more information on service
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description files.
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See [docs/bootup.md](docs/bootup.md) for more information on what the init
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daemon does during system boot.
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Right now, the system is in a "basically works" proof of concept stage and
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needs some more work to become usable.
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There are plans for *maybe* *eventually* adding support for Linux name
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spaces, seccomp filters and cgroups as needed in the medium future.
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## Why
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There are already a bunch of similar projects out there that have been
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considered for use in the Pygos system. The reason for starting a new
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one was mainly dissatisfaction with the existing ones. Other Projects
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that have been considered include:
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- systemd
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Contains a lot of good ideas, but it is HUGE. It has tons of
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dependencies. It implements tons of things that it simply shouldn't.
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It has a horrid, "modern", python based, hipster build system.
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It's simply too damn large and complex.
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- SystemV init
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A bad combination of unnecessary complexity where it isn't needed and a
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complete lack of abstraction where it would be needed. Shell script
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copy and paste madness. There are reasons people started developing
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alternatives (other than "hurr-durr-parallel-boots").
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- upstart
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Seems nice overall, but needlessly big and complex for the intended
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use case in Pygos. Would have needlessly added D-Bus to the system.
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- OpenRC
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Was already integrated into Pygos. Things turned out to be broken.
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Upstream developers did not accept fixes (after ignoring them for weeks
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and preferring typo fixes instead). Complaints from other people who
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tried to contribute fixes were observed on GitHub. Complaints from
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package maintainers about deteriorating code quality were observed
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on the official IRC channel. Documentation is non-existent.
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- daemon tools and similar (runnit, s6, minit, ...)
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The sixties are over. And even code from that era is more readable. The
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source code for those projects should better be tossed out the window and
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rewritten from scratch. If you are a first semester CS student and you
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hand something like this in as a homework, the best you might get is a
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well deserved slap on the back of your head.
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- busybox init
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Nice and simple. Probably the best fit if the rest of your user space is
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busybox as well.
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