5 ms·

Revisiting the NetBSD Build System

142 points by abhi9u 2y ago

kev009 2y ago
It's hard to overstate how awesome build.sh is. If you have some powerful desktop/laptop running virtually any modern POSIX OS, you can easily build for an embedded board like an RPi or Beagelboard, obscure retro targets, or standard systems all the same. The closest thing is maybe Yocto Linux, but a whole lot easier to use and understand.
- dgfitz 2y ago
  My yocto linux builds have a single entry point that is a build.sh. And they’re like 20 lines.
  - johnklos 2y ago
    I've heard this about various Linux distros, but every time I've tried it has never been as simple as people say it should be. I assume your twenty lines has customizations. How do you rebuild the OS and kernel the simplest way possible?
    - dgfitz 2y ago
      The short answer to the last question is, blow away the cache and download dirs and run build.sh My build.sh clones down 5 repos, inits the bitbake environment, and builds. This bit is 12-15 lines. Because I have to work around work infrastructure, about 10 lines of build.sh make symlinks into bitbakes previously-cloned folder structure for things that should be native recipes, but cannot be. Really no magic at all, the symlinks piss me off.
- idatum 2y ago
  If you run older hardware you realize quickly how significant it is to be able to do cross builds with build.sh. I came across this post today that highlights this! https://zia.io/objects/c4b825f9-8c57-4b86-a108-af869dfbcb10 https://zia.io/objects/c4b825f9-8c57-4b86-a108-af869dfbcb10 > How long would you imagine it might take to compile NetBSD 10 from source on real m68k hardware? Earlier this year I wanted to find out, so I set up a Macintosh to try it. > The toolchain, OS and installation sets started on 16-March and finished on 10-May: > build.sh started: Sat Mar 16 17:04:20 UTC 2024 > build.sh ended: Fri May 10 00:35:54 UTC 2024 > 4692724.22 real 3810544.56 user 700310.18 sys
  - kstrauser 2y ago
    I misread that. It started on Mar 16 and ended on Mar 10? How did that OHHHHhhhh...
  - actionfromafar 2y ago
    That's not so bad! :-D
deleted 2y ago
[deleted]
jmclnx 2y ago
I just updated pkgsrc from 2024Q3 to 2024Q4 for amd64 and i386, very easy. I never built NetBSD because I never had the need to do that. But from what I read its cross-compiling works very well.
theamk 2y ago
> NetBSD build system allows you to build the full OS from scratch, on pretty much any host POSIX platform, while targeting any hardware architecture supported by NetBSD. All without root privileges. That seems fairly standard to me though? Yocto, buldroot, many other embedded-oriented systems provide that and more.
- plorkyeran 2y ago
  It's definitely what I would consider the basic expectations for a build system (why would you even need root to compile an OS?), but it's not something that most non-embedded-focused distributions deliver.
  - musicale 2y ago
    > why would you even need root to compile an OS Usually it's to make it easier dealing with file system ("disk") image files, which may require root privileges to mount and use with regular programs (though FUSE and similar subsystems can help.) In a mounted filesystem, root privileges may be required to set permission bits like setuid. The NetBSD toolchain probably includes utilities to make it easy to copy data in and out of file system images, ideally concurrently and without corruption.
    - cperciva 2y ago
      In addition to building filesystem images, a common use of root for operating system building is to chroot into a "clean" environment to avoid environmental corruption. (In general, chroot is reserved to uid 0 due to issues with setuid binaries -- on some systems chroot can be made available to non-root users by turning off setuid behaviour.)
  - Koshkin 2y ago
    The option -U lets you build in the unprivileged mode.
  - deaddodo 2y ago
    Yeah, I feel like anyone making this statement hasn't done any sort of wide cross-compilation in the past, let alone of an entire OS. It should be a basic expectation, but most certainly isn't one in the real-world. Especially with stuff like GCC2 Haiku, which requires an old obscure GCC version for building ABI compatible images.
mikedesu 2y ago
[dead]
plagiarist 2y ago
I really enjoyed reading this. And it is too relatable that they would detour from the project they want to work on to port the build over to Bazel.

142 points by abhi9u 2y ago

It's hard to overstate how awesome build.sh is. If you have some powerful desktop/laptop running virtually any modern POSIX OS, you can easily build for an embedded board like an RPi or Beagelboard, obscure retro targets, or standard systems all the same. The closest thing is maybe Yocto Linux, but a whole lot easier to use and understand.

dgfitz 2y ago
My yocto linux builds have a single entry point that is a build.sh. And they’re like 20 lines.
- johnklos 2y ago
  I've heard this about various Linux distros, but every time I've tried it has never been as simple as people say it should be. I assume your twenty lines has customizations. How do you rebuild the OS and kernel the simplest way possible?
  - dgfitz 2y ago
    The short answer to the last question is, blow away the cache and download dirs and run build.sh My build.sh clones down 5 repos, inits the bitbake environment, and builds. This bit is 12-15 lines. Because I have to work around work infrastructure, about 10 lines of build.sh make symlinks into bitbakes previously-cloned folder structure for things that should be native recipes, but cannot be. Really no magic at all, the symlinks piss me off.
idatum 2y ago
If you run older hardware you realize quickly how significant it is to be able to do cross builds with build.sh. I came across this post today that highlights this! https://zia.io/objects/c4b825f9-8c57-4b86-a108-af869dfbcb10 https://zia.io/objects/c4b825f9-8c57-4b86-a108-af869dfbcb10 > How long would you imagine it might take to compile NetBSD 10 from source on real m68k hardware? Earlier this year I wanted to find out, so I set up a Macintosh to try it. > The toolchain, OS and installation sets started on 16-March and finished on 10-May: > build.sh started: Sat Mar 16 17:04:20 UTC 2024 > build.sh ended: Fri May 10 00:35:54 UTC 2024 > 4692724.22 real 3810544.56 user 700310.18 sys
- kstrauser 2y ago
  I misread that. It started on Mar 16 and ended on Mar 10? How did that OHHHHhhhh...
- actionfromafar 2y ago
  That's not so bad! :-D

deleted 2y ago

[deleted]

jmclnx 2y ago

I just updated pkgsrc from 2024Q3 to 2024Q4 for amd64 and i386, very easy. I never built NetBSD because I never had the need to do that. But from what I read its cross-compiling works very well.

theamk 2y ago

> NetBSD build system allows you to build the full OS from scratch, on pretty much any host POSIX platform, while targeting any hardware architecture supported by NetBSD. All without root privileges. That seems fairly standard to me though? Yocto, buldroot, many other embedded-oriented systems provide that and more.

plorkyeran 2y ago
It's definitely what I would consider the basic expectations for a build system (why would you even need root to compile an OS?), but it's not something that most non-embedded-focused distributions deliver.
- musicale 2y ago
  > why would you even need root to compile an OS Usually it's to make it easier dealing with file system ("disk") image files, which may require root privileges to mount and use with regular programs (though FUSE and similar subsystems can help.) In a mounted filesystem, root privileges may be required to set permission bits like setuid. The NetBSD toolchain probably includes utilities to make it easy to copy data in and out of file system images, ideally concurrently and without corruption.
  - cperciva 2y ago
    In addition to building filesystem images, a common use of root for operating system building is to chroot into a "clean" environment to avoid environmental corruption. (In general, chroot is reserved to uid 0 due to issues with setuid binaries -- on some systems chroot can be made available to non-root users by turning off setuid behaviour.)
- Koshkin 2y ago
  The option -U lets you build in the unprivileged mode.
- deaddodo 2y ago
  Yeah, I feel like anyone making this statement hasn't done any sort of wide cross-compilation in the past, let alone of an entire OS. It should be a basic expectation, but most certainly isn't one in the real-world. Especially with stuff like GCC2 Haiku, which requires an old obscure GCC version for building ABI compatible images.

mikedesu 2y ago

[dead]

plagiarist 2y ago

I really enjoyed reading this. And it is too relatable that they would detour from the project they want to work on to port the build over to Bazel.