add -h arg for help

[lnf] / lnf

diff --git a/lnf b/lnf
index 29f137df5f89acaa63075826a3801c2cf5333569..2518c1c4ac60cf35147ba72bdc886c252759bbe2 100755 (executable)
--- a/lnf
+++ b/lnf
@@ -1,22 +1,23 @@
 #!/bin/bash
-# Copyright (C) 2014 Ian Kelling
+# Copyright (C) 2014-2016 Ian Kelling
 # This program is under GPL v. 3 or later, see <http://www.gnu.org/licenses/>
 
 lnf() {
-    local help="lnf - Create symlinks conveniently and forcefully.
-Usage:
+    local help="Usage:
        lnf -T TARGET LINK_NAME     (1st form)
        lnf TARGET                  (2nd form)
        lnf TARGET... DIRECTORY     (3rd form)
+Create symlinks forcefully
 
-Remove existing file in the using trash-put or rm -rf if it is not available.
+Removes existing files using trash-put or rm -rf if it is not available,
+or trash-put fails due to a limitation such as a cross-filesystem link.
 Create directory 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
+
+    if [[ $1 == --help || $1 == -h || $# -eq 0 ]]; then
         echo "$help"
         return 0
     fi
@@ -30,38 +31,36 @@ links to each TARGET in DIRECTORY."
             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 x ret prefix dir to_remove
+    local mkdir=false
+
+    to_remove=()
     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 "$2")"
-            return 1
+        dir="$(dirname "$2")"
+        if [[ -e $2 || -L $2 ]]; then
+            to_remove+=("$2")
+        elif [[ ! -d $dir ]]; then
+            mkdir=true
+            if [[ -e $dir || -L $dir ]]; then
+                to_remove+=("$dir")
+            fi
         fi
     elif (( $# >= 2 )); then
         if [[ -d ${!#} ]]; then
-            local oldcwd=$PWD
-            cd "${!#}" # last arg
+            prefix="${!#}/" # last arg
             for x in "${@:1:$(( $# - 1 ))}"; do # all but last arg
-                # remove any trailing slashes, uses extglob
+                # Remove 1 or more trailing slashes, using.
                 x="${x%%+(/)}"
-                # remove any leading directory components
-                x="${x##*/}"
-                [[ -e "$x" || -L "$x" ]] && $remove "$x"
+                # remove any leading directory components, add prefix
+                x="$prefix/${x##*/}"
+                [[ -e "$x" || -L "$x" ]] && to_remove+=("$x")
             done
-            cd "$oldcwd"
         else
             if ! mkdir -p "${!#}"; then
                 echo "lnf error: failed to make directory ${!#}"
@@ -69,10 +68,37 @@ links to each TARGET in DIRECTORY."
             fi
         fi
     elif  [[ $# -eq 1 ]]; then
-        [[ -e "${1##*/}" || -L "${1##*/}" ]] && $remove "${1##*/}"
+        [[ -e "${1##*/}" || -L "${1##*/}" ]] && to_remove+=("${1##*/}")
+    fi
+    if (( ${#to_remove[@]} >= 1 )); then
+        if type -P trash-put >/dev/null; then
+            trash-put -- "${to_remove[@]}" || ret=$?
+            # 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 "$0: using rm -rf to overcome cross filesystem trash-put limitation"
+                rm -rf -- "${to_remove[@]}"
+            elif [[ $ret == 74 ]]; then
+                echo "$0: using rm -rf to overcome empty file & hardlink trash-put limitation"
+                rm -rf -- "${to_remove[@]}"
+            elif [[ $ret && $ret != 0 ]]; then
+                return $x
+            fi
+        else
+            rm -rf -- "${to_remove[@]}"
+        fi
+    fi
+
+    $reset_extglob && shopt -u extglob
+
+    if $mkdir; then
+        if ! mkdir -p "$(dirname "$2")"; then
+            echo "lnf error: failed to make directory $(dirname "$2")"
+            return 1
+        fi
     fi
 
-    $reset_extglob && shopt -u extglob 
     ln -s $nodir -- "$@"
 }
 lnf "$@"