[pacman-dev] [PATCH] repo-add: added a realpath implementation in bash

[Yun Zheng Hu]

When realpath or readlink is not available it will fallback to a
realpath implementation in bash. An extra check is also added for
"readlink -f", because not all platforms support the -f flag.

The readlink implementation in bash is borrowed from Debian's dpkg tools.

Signed-off-by: Yun Zheng Hu <yunzheng.hu at gmail.com>
---
 scripts/repo-add.sh.in |   23 ++++++++++++++++++++---
 1 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/scripts/repo-add.sh.in b/scripts/repo-add.sh.in
index c89e2a5..ea16731 100644
--- a/scripts/repo-add.sh.in
+++ b/scripts/repo-add.sh.in
@@ -297,11 +297,28 @@ fi
 # check for and store the name of a realpath-like program
 if [ $(type -t realpath) ]; then
 	realpath='realpath'
-elif [ $(type -t readlink) ]; then
+elif [ $(type -t readlink) -a "$(readlink -f . 2>/dev/null)" != "" ]; then
 	realpath='readlink -f'
 else
-	error "$(gettext "Either realpath or readlink are required by repo-add.")"
-	exit 1 # $E_MISSING_PROGRAM
+	realpath_bash()
+	{
+		fname=${1%/} # strips trailing '/'
+		while [ -L "$fname" ]; do
+			oldfname="$fname"
+			fname="$(command ls -l $fname)"
+			fname="${fname#*\> }"
+			if [ "$fname" = . ] ; then
+				fname="$(dirname $oldfname)"
+			elif echo $fname | grep -vq '^/' - ; then
+				fname="$(dirname $oldfname)/$fname"
+			fi
+		done
+		pushd $(dirname $fname) > /dev/null
+		fname=$(pwd -P)/$(basename $fname)
+		popd > /dev/null
+		echo $fname
+	}
+	realpath=realpath_bash
 fi

 # main routine
-- 
1.6.1.2