git-repo

git-repo (5542B)

---

 #!/bin/sh
 
 # Copyright (C) 2024, 2025 |Méso|Star> (contact@meso-star.com)
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 
 set -e
 
 git_repo_tmpdir="$(mktemp -d "${TMPDIR:-/tmp}/git_repo_XXXXXX")"
 
 die()
 {
   rm -rf "${git_repo_tmpdir}" # cleanup temporary files
   exit "${1:-1}" # return status code (default is 1)
 }
 
 # Configure signal processing
 trap 'die $?' EXIT
 
 ########################################################################
 # Helper functions
 ########################################################################
 synopsis()
 {
   cmd="${0##*/}"
   >&2 printf 'usage: %s [-Ddp] [-s group] directory\n' "${cmd}"
 }
 
 # Print group permissions to be sent to chmod to make a file private
 grp_priv_perm() # file
 (
   # shellcheck disable=SC2012
   grp="$(ls -dl "$1" | cut -d' ' -f1 | cut -c5-7)"
 
   # Disable the write and set-group-ID-on-execution permissions if there
   # are not default file permissions
   if ! printf '%s\n' "${grp}" | grep -e 'w'; then
     perm="${perm}w"
   fi
 
   if ! printf '%s\n' "${perm}" | grep -e '[sS]'; then
     perm="${perm}s"
   fi
 
   printf 'g-%s\n' "${perm}"
 )
 
 # Print group permissions to be sent to chmod to make a regular file
 # private
 file_grp_priv_perm()
 (
   f="${git_repo_tmpdir}/file"
   touch "${f}"
   grp_priv_perm "${f}"
 )
 
 # Print group permissions to be sent to chmod to make a directory
 # private
 dir_grp_priv_perm()
 (
   d="${git_repo_tmpdir}/dir"
   mkdir -p "${d}"
   grp_priv_perm "${d}"
 )
 
 # Share the repository
 share() # repo, group
 (
   u="$(id -un)"
 
   # Search for files in the repository that do NOT belong to the user.
   # If there are any, the repository permissions cannot be updated.
   f="$(find "$1" ! -user "${u}")"
   if [ -n "${f}" ]; then
     >&2 printf 'Could not share the repository: '\
 'some files do not belong to %s\n' "${u}"
     die
   fi
 
   chown -R :"$2" "$1"
   find "$1" -type f -exec chmod "g+w" {} \;
   find "$1" -type d -exec chmod "g+ws" {} \;
   cd -- "$1"
   git config --local core.sharedRepository group
   cd -- "${OLDPWD}"
 )
 
 # Do not share the repository and define the group as the user's group
 privatise() # repo
 (
   u="$(id -un)"
   g="$(id -gn)"
 
   # Search for files in the repository that do NOT belong to the user.
   # If there are any, the repository permissions cannot be updated.
   f="$(find "$1" ! -user "${u}")"
   if [ -n "${f}" ]; then
     >&2 printf 'Could not privatise the repository: '\
 'some files do not belong to %s\n' "${u}"
     die
   fi
 
   fgperm="$(file_grp_priv_perm)"
   dgperm="$(dir_grp_priv_perm)"
 
   chown -R :"${g}" "$1"
   find "$1" -type f -exec chmod "${fgperm}" {} \;
   find "$1" -type d -exec chmod "${dgperm}" {} \;
   cd -- "$1"
   git config --local core.sharedRepository false
   cd -- "${OLDPWD}"
 )
 
 dumb() # git_dir
 (
   if [ -f "$1"/hooks/post-update.sample ]; then
     mv "$1"/hooks/post-update.sample "$1"/hooks/post-update
     cd -- "$1"/hooks/
     ./post-update || die "$?"
     cd -- "${OLDPWD}"
   fi
 )
 
 nodumb() # git_dir
 (
   if [ -f "$1"/hooks/post-update ]; then
     mv "$1"/hooks/post-update "$1"/hooks/post-update.sample
   fi
 )
 
 ########################################################################
 # The script
 ########################################################################
 nodumb=0
 dumb=0
 privatise=0
 group=""
 
 # Parse input arguments
 OPTIND=1
 while getopts ":dDps:" opt; do
   case "${opt}" in
     D) nodumb=1 ;;
     d) dumb=1 ;;
     p) privatise=1 ;;
     s) group="${OPTARG}" ;;
     *) synopsis; die ;;
   esac
 done
 
 [ "${OPTIND}" -gt "$#" ] && { synopsis; die;  }
 
 # Skip parsed arguments
 shift $((OPTIND - 1))
 
 repo="$1"
 
 # The input repository does not exist
 if [ ! -e "${repo}" ]; then
 
   # Remove trailing slashes
   repo="$(echo "${repo}" | sed 's#/\+$##g')"
 
   # Ensure that the repository name includes the .git extension, in
   # accordance with the convention applicable to bare repositories.
   suffix="${repo##*.}"
   if [ "${suffix}" != "git" ] \
   || [ "${suffix}" = "${repo}" ];  then
     repo="${repo}.git"
   fi
 
   mkdir -p "${repo}"
   git init --bare "${repo}"
 
   git_dir="${repo}"
 
 # Verify that the existing path is indeed a bare git repository
 else
   # Check that it is a directory
   if [ ! -d "${repo}" ]; then
     >&2 printf '%s: not a git repository\n' "${repo}"
     die
   fi
 
   cd -- "${repo}"
 
   # Retrieve the "git" directory, i.e., the directory where git data is
   # stored
   if ! git_dir=$(git rev-parse --path-format=absolute --git-dir 2>&1)
   then
     >&2 printf '%s: %s\n' "${repo}" "${git_dir}"
     die
   fi
 
   # Check that the repository is a bare repository
   if ! git_bare=$(git rev-parse --is-bare-repository) \
   || [ "${git_bare}" = "false" ]; then
     >&2 printf '%s: not a git bare repository\n' "${repo}"
     die
   fi
 
   cd -- "${OLDPWD}"
 fi
 
 if [ -n "${group}" ]; then
   share "${repo}" "${group}"
 fi
 
 if [ "${privatise}" -ne 0 ]; then
   privatise "${repo}"
 fi
 
 if [ "${dumb}" -ne 0 ]; then
   dumb "${git_dir}"
 fi
 
 if [ "${nodumb}" -ne 0 ]; then
   nodumb "${git_dir}"
 fi