1 files changed, 70 insertions, 0 deletions
diff --git a/contrib/wget-xdelta.sh.in b/contrib/wget-xdelta.sh.in
new file mode 100755
index 00000000..4656f4dd
--- /dev/null
+++ b/contrib/wget-xdelta.sh.in
@@ -0,0 +1,70 @@
+#!/bin/bash
+
+if [ -r "/etc/makepkg.conf" ]; then
+	source /etc/makepkg.conf
+else
+	echo "wget-xdelta: Unable to find makepkg.conf"
+	exit 1
+fi
+
+if [ -r ~/.makepkg.conf ]; then
+	source ~/.makepkg.conf
+fi
+
+out_file=$(basename $1)
+file_url=$2
+
+if ! [[ "$out_file" =~ "pkg.tar.gz" ]]; then
+	# If it's not a package file download as normal and exit.
+	#wget --passive-ftp -c -O "$out_file" "$file_url"
+	exit $?
+fi
+
+
+# Get the package name and version
+[[ "$out_file" =~ "$CARCH" ]] && arch="-$CARCH" || arch=""
+pkg_data=$(echo $out_file | \
+	sed "s|^\(.*\)-\([[:alnum:]_\.]*-[[:alnum:]_\.]*\)${arch}${PKGEXT}.part|\1 \2|")
+pkgname=$(echo $pkg_data | cut -d ' ' -f 1)
+new_version=$(echo $pkg_data | cut -d ' ' -f 2)
+base_url=${file_url%/*}
+
+# Look for the last version
+for file in $(ls -r /var/cache/pacman/pkg/${pkgname}-*-*{,-$CARCH}$PKGEXT 2>/dev/null); do
+	[[ "$file" =~ "$CARCH" ]] && arch="-$CARCH" || arch=""
+	check_version=$(echo $file | \
+		sed "s|^.*/${pkgname}-\([[:alnum:]_\.]*-[[:alnum:]_\.]*\)${arch}$PKGEXT$|\1|" | \
+		grep -v "^/var/cache/pacman/pkg")
+
+	[ "$check_version" = "" ] && continue
+
+	vercmp=$(vercmp "$check_version" "$old_version")
+	if [ "$check_version" != "$new_version" -a $vercmp -gt 0 ]; then
+		old_version=$check_version
+		old_file=$file
+	fi
+done
+
+if [ "$old_version" != "" -a "$old_version" != "$new_version" ]; then
+	# Great, we have a cached file, now calculate a patch name from it
+	delta_name="$pkgname-${old_version}_to_${new_version}-${CARCH}.delta"
+
+	echo "wget-xdelta: Attempting to download delta $delta_name..." >&2
+	if wget --passive-ftp -c "$base_url/$delta_name"; then
+		echo "wget-xdelta: Applying delta..."
+		if xdelta patch "$delta_name" "$old_file" "$out_file"; then
+			echo "wget-xdelta: Delta applied successfully!"
+			rm "$delta_name"
+			exit 0
+		else
+			echo "wget-xdelta: Failed to apply delta!"
+			rm $delta_name
+		fi
+	fi
+ fi
+
+echo "wget-xdelta: Downloading new package..."
+wget --passive-ftp -c -O "$out_file" "$file_url"
+exit $?
+
+# vim:set ts=4 sw=4 noet: