sde-build: warn about absolute, dirty and broken symlinks

lib/functions.in

@@ -311,12 +311,29 @@ function run_check() {
 # make symlinks relative
 #
 postflist_dirty_symlinks() {
-	local dfn= ffn=
 	echo "Processing symlink corrections ..."
+
 	while read fn; do
 		local ffn="$root/$fn"
-		if [ -L "$ffn" -a ! -e "$ffn" ]; then
-			echo_warning "broken symlink: $fn"
+		if [ -L "$ffn" ]; then
+			local dfn=$(readlink "$ffn")
+			if [ "${dfn:0:1}" = '/' ]; then
+				local dfn2="${dfn#$root}"
+				if [ "$dfn2" != "$dfn" ]; then
+					echo_warning "dirty symlink: $fn"
+					dfn="$dfn2"
+				else
+					dfn2=
+				fi
+
+				if [ ! -e "$root$dfn" ]; then
+					echo_warning "broken absolute symlink: $fn"
+				elif [ -z "$dfn2" ]; then # haven't said it's dirty already
+					echo_warning "absolute symlink: $fn"
+				fi
+			elif [ ! -e "$ffn" ]; then
+				echo_warning "broken symlink: $fn"
+			fi
 		fi
 	done < "$builddir/flist.txt"
 }