X-Git-Url: https://iankelling.org/git/?p=lnf;a=blobdiff_plain;f=lnf;h=0620b32929d87c19ef5f79217094a9012f3df3ce;hp=29f137df5f89acaa63075826a3801c2cf5333569;hb=027b72114fc778535fae4a83c497dc47f71dedbd;hpb=056e6160cd38fa3bf1622ed4f4c0179f84b53c2f diff --git a/lnf b/lnf index 29f137d..0620b32 100755 --- a/lnf +++ b/lnf @@ -1,78 +1,184 @@ #!/bin/bash -# Copyright (C) 2014 Ian Kelling +# Copyright (C) 2014-2016 Ian Kelling # This program is under GPL v. 3 or later, see +_lnf_existing_link() { + local target dest_file dest_dir + target="$1" + dest_file="$2" + dest_dir="$3" + if [[ -L $dest_file ]]; then + if [[ $(readlink $dest_file) == "$target" ]]; then + # Leave the link in place, but make sure it's + # owner & group is as if we created it. + # links all get 777 perms, so + # we already know that is right. + + # test for setgid. + if [[ $(stat -L -c%a "$dest_dir") == 2??? ]]; then + grp=$(stat -L -c%g "$dest_dir") || return $? + else + grp=$(id -g) || return $? + fi + if [[ $EUID == 0 && $(stat -c%u "$dest_file") != 0 ]]; then + chown -h 0:$grp "$dest_file" || return $? + elif [[ $(stat -c%g "$dest_file") != "$grp" ]]; then + chgrp -h $grp "$dest_file" || return $? + fi + do_exit=true + return 0 + fi + to_remove+=("$dest_file") + elif [[ -e $dest_file ]]; then + to_remove+=("$dest_file") + fi + to_link+=("$target") +} lnf() { - local help="lnf - Create symlinks conveniently and forcefully. -Usage: - lnf -T TARGET LINK_NAME (1st form) - lnf TARGET (2nd form) - lnf TARGET... DIRECTORY (3rd form) + local help="Usage: + lnf [OPTIONS] -T TARGET LINK_NAME (1st form) + lnf [OPTIONS] TARGET (2nd form) + lnf [OPTIONS] TARGET... DIRECTORY (3rd form) +Create symlinks forcefully -Remove existing file in the using trash-put or rm -rf if it is not available. -Create directory if needed. Slightly more restrictive arguments than ln. +If the link already exists, make it's ownership be the same as if it was +newly created (only chown if we are root). Removes existing files using +trash-put or rm -rf if it is not available, or if trash-put fails due to a +limitation such as a cross-filesystem link. Create directory of link if +needed. Slightly more restrictive arguments than ln. In the 1st form, create a link to TARGET with the name LINK_NAME. In the 2nd form, create a link to TARGET in the current directory. In the 3rd form, create -links to each TARGET in DIRECTORY." - - if [[ $1 == --help || $# -eq 0 ]]; then +links to each TARGET in DIRECTORY. + +-n|--dry-run Do verbose dry run. +-v|--verbose Print commands which modify the filesystem. +-h|--help Print help and exit. +" + + + local temp nodir + local verbose=false + local dry_run=false + local do_exit=false + temp=$(getopt -l help,dry-run,verbose hnTv "$@") || usage 1 + eval set -- "$temp" + while true; do + case $1 in + -n|--dry-run) dry_run=true; verbose=true; shift ;; + -T) nodir=-T; shift ;; + -v|--verbose) verbose=true; shift ;; + -h|--help) echo "$help"; return 0 ;; + --) shift; break ;; + *) echo "$0: Internal error! unexpected args: $*" ; exit 1 ;; + esac + done + + if (( $# == 0 )); then echo "$help" - return 0 + return 1 fi - local nodir - if [[ $1 == -T ]]; then - nodir=-T - shift + if [[ $nodir ]]; then if (( $# != 2 )); then - echo "lnf error: expected 2 arguments with -T flag. Got $#" + echo "lnf: error: expected 2 arguments with -T flag. Got $#" return 1 fi fi - + local reset_extglob=false ! shopt extglob >/dev/null && reset_extglob=true shopt -s extglob - - local remove x - if type -P trash-put >/dev/null; then - remove=trash-put - else - remove="rm -rf" - fi - + + local -a to_remove to_link + local x ret prefix dest_dir grp target + local mkdir=false + if [[ $nodir ]]; then - if [[ -e "$2" || -L "$2" ]]; then - $remove "$2" - elif ! mkdir -p "$(dirname "$2")"; then - echo "lnf error: failed to make directory $(dirname "$2")" - return 1 + dest_file="$2" + dest_dir="$(dirname "$dest_file")" + _lnf_existing_link "$1" "$dest_file" "$dest_dir" || return $? + if $do_exit; then return 0; fi + if [[ ! -d $dest_dir ]]; then + mkdir=true + if [[ -e $dest_dir || -L $dest_dir ]]; then + to_remove+=("$dest_dir") + fi fi + to_link+=("$dest_file") elif (( $# >= 2 )); then - if [[ -d ${!#} ]]; then - local oldcwd=$PWD - cd "${!#}" # last arg - for x in "${@:1:$(( $# - 1 ))}"; do # all but last arg - # remove any trailing slashes, uses extglob - x="${x%%+(/)}" - # remove any leading directory components - x="${x##*/}" - [[ -e "$x" || -L "$x" ]] && $remove "$x" + dest_dir="${!#}" + if [[ -d $dest_dir ]]; then + prefix="$dest_dir" # last arg + for target in "${@:1:$(( $# - 1 ))}"; do # all but last arg + # Remove 1 or more trailing slashes, using. + dest_file="${target%%+(/)}" + # remove any leading directory components, add prefix + dest_file="$prefix/${target##*/}" + _lnf_existing_link "$target" "$dest_file" "$dest_dir" done - cd "$oldcwd" else - if ! mkdir -p "${!#}"; then - echo "lnf error: failed to make directory ${!#}" - return 1 - fi + to_link+=("${@:1:$(( $# - 1 ))}") + mkdir=true fi + if (( ${#to_link[@]} == 0 )); then + return 0 + fi + to_link+=("$dest_dir") elif [[ $# -eq 1 ]]; then - [[ -e "${1##*/}" || -L "${1##*/}" ]] && $remove "${1##*/}" + dest_file="${1##*/}" + _lnf_existing_link "$1" "$dest_file" . || return $? + if $do_exit; then return 0; fi + fi + if (( ${#to_remove[@]} >= 1 )); then + if type -P trash-put >/dev/null; then + if $verbose; then + echo "lnf: trash-put -- ${to_remove[*]}" + fi + if ! $dry_run; then + trash-put -- "${to_remove[@]}" || ret=$? + fi + # trash-put will fail to trash a link that goes across filesystems (72), + # and for empty files (74) + # so revert to rm -rf in that case + if [[ $ret == 72 ]]; then + echo "lnf: using rm -rf to overcome cross filesystem trash-put limitation" + rm -rf -- "${to_remove[@]}" || return $? + elif [[ $ret == 74 ]]; then + echo "lnf: using rm -rf to overcome empty file & hardlink trash-put limitation" + rm -rf -- "${to_remove[@]}" + elif [[ $ret && $ret != 0 ]]; then + return $x + fi + else + if $verbose; then + echo "lnf: rm -rf -- ${to_remove[*]}" + fi + if ! $dry_run; then + rm -rf -- "${to_remove[@]}" + fi + fi fi - $reset_extglob && shopt -u extglob - ln -s $nodir -- "$@" + $reset_extglob && shopt -u extglob + + if $mkdir; then + if $verbose; then + echo "lnf: mkdir -p $dest_dir" + fi + + if ! $dry_run && ! mkdir -p "$dest_dir"; then + echo "lnf error: failed to make directory $dest_dir" + return 1 + fi + fi + + if $verbose; then + echo "lnf: ln -s $nodir -- ${to_link[*]}" + fi + if ! $dry_run; then + ln -s $nodir -- "${to_link[@]}" + fi } lnf "$@"