home-manager/modules/lib-bash/activation-init.sh
Robert Helgesson 567b21b1d6
activation-init: sanity check oldGenNum and oldGenPath
Something is terribly wrong if one is set but not the other so error
out with a message if that happens.
2018-03-13 20:49:45 +01:00

84 lines
2.4 KiB
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Executable file

#!/usr/bin/env bash
function setupVars() {
local profilesPath="/nix/var/nix/profiles/per-user/$USER"
local gcPath="/nix/var/nix/gcroots/per-user/$USER"
local greatestGenNum
greatestGenNum=$( \
find "$profilesPath" -name 'home-manager-*-link' \
| sed 's/^.*-\([0-9]*\)-link$/\1/' \
| sort -rn \
| head -1)
if [[ -n $greatestGenNum ]] ; then
oldGenNum=$greatestGenNum
newGenNum=$((oldGenNum + 1))
else
newGenNum=1
fi
if [[ -e $gcPath/current-home ]] ; then
oldGenPath="$(readlink -e "$gcPath/current-home")"
fi
$VERBOSE_ECHO "Sanity checking oldGenNum and oldGenPath"
if [[ -v oldGenNum && ! -v oldGenPath
|| ! -v oldGenNum && -v oldGenPath ]]; then
errorEcho "Invalid profile number and GC root values! These must be"
errorEcho "either both empty or both set but are now set to"
errorEcho " '${oldGenNum:-}' and '${oldGenPath:-}'"
errorEcho "If you don't mind losing previous profile generations then"
errorEcho "the easiest solution is probably to run"
errorEcho " rm $profilesPath/home-manager*"
errorEcho " rm $gcPath/current-home"
errorEcho "and trying home-manager switch again. Good luck!"
exit 1
fi
genProfilePath="$profilesPath/home-manager"
newGenPath="@GENERATION_DIR@";
newGenProfilePath="$profilesPath/home-manager-$newGenNum-link"
newGenGcPath="$gcPath/current-home"
}
if [[ -v VERBOSE ]]; then
export VERBOSE_ECHO=echo
export VERBOSE_ARG="--verbose"
else
export VERBOSE_ECHO=true
export VERBOSE_ARG=""
fi
echo "Starting home manager activation"
setupVars
if [[ -v DRY_RUN ]] ; then
echo "This is a dry run"
export DRY_RUN_CMD=echo
else
$VERBOSE_ECHO "This is a live run"
export DRY_RUN_CMD=""
fi
if [[ -v VERBOSE ]]; then
echo -n "Using Nix version: "
nix-env --version
fi
$VERBOSE_ECHO "Activation variables:"
if [[ -v oldGenNum ]] ; then
$VERBOSE_ECHO " oldGenNum=$oldGenNum"
$VERBOSE_ECHO " oldGenPath=$oldGenPath"
else
$VERBOSE_ECHO " oldGenNum undefined (first run?)"
$VERBOSE_ECHO " oldGenPath undefined (first run?)"
fi
$VERBOSE_ECHO " newGenPath=$newGenPath"
$VERBOSE_ECHO " newGenNum=$newGenNum"
$VERBOSE_ECHO " newGenProfilePath=$newGenProfilePath"
$VERBOSE_ECHO " newGenGcPath=$newGenGcPath"
$VERBOSE_ECHO " genProfilePath=$genProfilePath"