[src/trunk]: src/usr.sbin/postinstall Add bre_quote (copied from etcupdate), ...

[apb <apb%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/1efe321058a8
branches:  trunk
changeset: 796739:1efe321058a8
user:      apb <apb%NetBSD.org@localhost>
date:      Mon Jun 16 08:21:20 2014 +0000

description:
Add bre_quote (copied from etcupdate), and unprefix functions.

diffstat:

 usr.sbin/postinstall/postinstall |  29 ++++++++++++++++++++++++++++-
 1 files changed, 28 insertions(+), 1 deletions(-)

diffs (45 lines):

diff -r 14b8645aecd0 -r 1efe321058a8 usr.sbin/postinstall/postinstall
--- a/usr.sbin/postinstall/postinstall  Mon Jun 16 07:11:52 2014 +0000
+++ b/usr.sbin/postinstall/postinstall  Mon Jun 16 08:21:20 2014 +0000
@@ -1,6 +1,6 @@
 #!/bin/sh
 #
-# $NetBSD: postinstall,v 1.167 2014/06/16 07:08:06 apb Exp $
+# $NetBSD: postinstall,v 1.168 2014/06/16 08:21:20 apb Exp $
 #
 # Copyright (c) 2002-2008 The NetBSD Foundation, Inc.
 # All rights reserved.
@@ -128,6 +128,33 @@
        printf "%s\n" "$result"
 }
 
+# Convert arg $1 to a basic regular expression (as in sed)
+# that will match the arg.  This works by inserting backslashes
+# before characters that are special in basic regular expressions.
+# It also inserts backslashes before the extra characters specified
+# in $2 (which defaults to "/,").
+# XXX: Does not handle embedded newlines.
+# Usage: regex="$(bre_quote "${string}")"
+bre_quote()
+{
+       local arg="$1"
+       local extra="$2:/,"
+       printf "%s\n" "${arg}" | ${SED} -e 's/[][^$.*\\'"${extra}"']/\\&/g'
+}
+
+# unprefix dir
+#      Remove any dir prefix from a list of paths on stdin,
+#      and write the result to stdout.  Useful for converting
+#      from ${DEST_DIR}/path to /path.
+#
+unprefix()
+{
+       [ $# -eq 1 ] || err 3 "USAGE: unprefix dir"
+       local prefix="${1#/}"
+       prefix="$(bre_quote "${prefix}")"
+
+       ${SED} -e "s,^${prefix}/,/,"
+}
 
 # additem item description
 #      Add item to list of supported items to check/fix,