From: Etienne Mollier <etienne.mollier@mailoo.org>
Date: Thu, 21 May 2020 15:20:18 +0000 (+0200)
Subject: bash-completion/umount: shell charaters escape
X-Git-Tag: v2.36-rc1~75^2
X-Git-Url: http://git.ipfire.org/?p=thirdparty%2Futil-linux.git;a=commitdiff_plain;h=2c12297400859d012b101c049e328eb19f705fe8

bash-completion/umount: shell charaters escape

This patch brings support for automatic dangerous shell characters
escape in umount autocompletion.  Due to the very peculiar way for
bash to handle autocompletion routines, proper escaping of the shell
sequences only worked properly inside a function: _umount_point_list,
which will add to the user's namespace at the next umount attempt of
autocompleting mount point.

It also translates calls of gensub to the portable alternatives sub
and gsub, in order to allow the use of various awk implementations
(mawk, Gnu, Busybox, etc), and as such kind of undoes a recent change
to enforce the use of Gnu awk. The whole story landed into the Debian
BTS initially:

	https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=933934

PS: It's been a few months since the patch is available, sorry for the
    delay; I only got myself a Github account quite recently...

Signed-off-by: Étienne Mollier <etienne.mollier@mailoo.org>
---

diff --git a/bash-completion/umount b/bash-completion/umount
index 0949688f93..2988c42f39 100644
--- a/bash-completion/umount
+++ b/bash-completion/umount
@@ -1,3 +1,27 @@
+_umount_points_list()
+{
+	# List of characters to escape shamelessly stolen from "scp" completion
+	local escape_chars='[][(){}<>\",:;^&!$=?`|\\'\'' \t\f\n\r\v]'
+
+	findmnt -lno TARGET | awk '{
+		if ($0 ~ "^"ENVIRON["HOME"]) {
+			homeless = $0
+			sub("^"ENVIRON["HOME"], "~", homeless)
+			gsub("'"$escape_chars"'", "\\\\&", homeless)
+			print homeless " "
+		}
+		if ($0 ~ "^"ENVIRON["PWD"]) {
+			reldir = $0
+			sub("^"ENVIRON["PWD"]"/?", "", reldir)
+			gsub("'"$escape_chars"'", "\\\\&", reldir)
+			print "./" reldir " "
+			print reldir " "
+		}
+		gsub("'"$escape_chars"'", "\\\\&")
+		print $0 " "
+	}'
+}
+
 _umount_module()
 {
 	local cur prev OPTS
@@ -49,27 +73,7 @@ _umount_module()
 			;;
 	esac
 
-	local oldifs=$IFS
-	IFS=$'\n'
-	COMPREPLY=( $( compgen -W "$(findmnt -lno TARGET | gawk \
-		'{
-			if ($0 ~ ENVIRON["HOME"]) {
-				homeless = $0
-				homeless = gensub(ENVIRON["HOME"], "\\\\~", "g", homeless)
-				homeless = gensub(/(\s)/, "\\\\\\1", "g", homeless)
-				print homeless
-			}
-			if ($0 ~ ENVIRON["PWD"]) {
-				reldir = $0
-				reldir = gensub(ENVIRON["PWD"]"/", "", "g", reldir)
-				reldir = gensub(/(\s)/, "\\\\\\1", "g", reldir)
-				print "./" reldir
-				print reldir
-			}
-			gsub(/\s/, "\\\\&")
-			print $0
-		}'
-	)" -- "$cur" ) )
-	IFS=$oldifs
+	local IFS=$'\n'
+	COMPREPLY=( $( compgen -W '$( _umount_points_list )'  -- "$cur" ) )
 }
-complete -F _umount_module umount
+complete -F _umount_module -o nospace umount