run_after_git_pull

#!/bin/sh
#
#	run_after_git_pull - Correct own/mod when git repo does not belong to us
#
Prg=$(basename "$0")
Cfg='.git/config'

test -s $Cfg || { echo "No '$Cfg' in '$PWD' - nothing to do"; exit 0; }
Usr=$(stat -c '%U' $Cfg)
Own=$(id -un)
#   We assume that the owner of $Cfg is the true owner of the git repo
test "$Own" = "$Usr" && { echo "File '$Cfg' belongs to us - nothing to do"; exit 0; }

NotUsr=$(find . ! -user $Usr | sed 's/^..//')
NotGrp=$(find . ! -perm -g=w | sed 's/^..//')
test "$NotUsr" -o "$NotGrp" || { echo "All files belong to $Usr and have g+w permission"; exit 0; }

Nb=$(echo "$NotUsr" | wc -l)
if [ $Nb -gt 0 ]; then
    test $Nb -gt 1 && { s='s'; its='their'; } || { es='es'; t='s'; its='its'; }
    echo "NOTE: $Nb file$s do$es not belong to $Usr and need$t $its ownership to be corrected"
    echo "$NotUsr" | sudo xargs chown -v "$Usr:" | sed -u 's/^c/C/'
    unset s es t its
fi

Nb=$(echo "$NotGrp" | wc -l)
if [ $Nb -gt 0 ]; then
    test $Nb -gt 1 && { s='s'; its='their'; } || { es='es'; t='s'; its='its'; }
    echo "NOTE: $Nb file$s do$es not have g+w permission and need$t $its mode to be corrected"
    echo "$NotGrp" | sudo xargs chmod -v ug+w | sed -u 's/^m/M/'
fi