Commit 5f3aad00 authored by Bryan Lai's avatar Bryan Lai
Browse files

checkpointBuildTools: minor refactor 



Add some minor improvements of the package, and use temp files for the
source difference patch, such that it is more reliable. This follows
from the suggestions of @infinisil.

Co-authored-by: default avatarRobert Hensing <roberth@users.noreply.github.com>
parent df62c3c8

pkgs/build-support/checkpoint-build.nix

+24 −8
Original line number Diff line number Diff line 
{ pkgs }:

{ lib

, buildPackages

}:



let

  # rudimentary support for cross-compiling

  # see: https://github.com/NixOS/nixpkgs/pull/279487#discussion_r1444449726

  inherit (buildPackages)

    mktemp

    rsync

    ;

in



rec {

  /* Prepare a derivation for local builds.

    *
@@ -51,23 +63,27 @@ rec { 
    *   checkpointArtifacts = prepareCheckpointBuild drv

    * in mkCheckpointBuild drv checkpointArtifacts

  */

  mkCheckpointBuild = drv: previousBuildArtifacts: drv.overrideAttrs (old: {

  mkCheckpointBuild = drv: checkpointArtifacts: drv.overrideAttrs (old: {

    # The actual checkpoint build phase.

    # We compare the changed sources from a previous build with the current and create a patch

    # Afterwards we clean the build directory to copy the previous output files (Including the sources)

    # The source difference patch is applied to get the latest changes again to allow short build times.

    preBuild = (old.preBuild or "") + ''

      set +e

      diff -ur ${previousBuildArtifacts}/sources ./ > sourceDifference.patch

      sourceDifferencePatchFile=$(${mktemp}/bin/mktemp)

      diff -ur ${checkpointArtifacts}/sources ./ > "$sourceDifferencePatchFile"

      set -e

      shopt -s extglob dotglob

      rm -r !("sourceDifference.patch")

      ${pkgs.rsync}/bin/rsync -cutU --chown=$USER:$USER --chmod=+w -r ${previousBuildArtifacts}/outputs/* .

      patch -p 1 -i sourceDifference.patch

      shopt -s dotglob

      rm -r *

      ${rsync}/bin/rsync \

        --checksum --times --atimes --chown=$USER:$USER --chmod=+w \

        -r ${checkpointArtifacts}/outputs/ .

      patch -p 1 -i "$sourceDifferencePatchFile"

      rm "$sourceDifferencePatchFile"

    '';

  });



  mkCheckpointedBuild = pkgs.lib.warn

  mkCheckpointedBuild = lib.warn

    "`mkCheckpointedBuild` is deprecated, use `mkCheckpointBuild` instead!"

    mkCheckpointBuild;

}