+ifeq ($(strip $(PKG_UNPACK)),)
+ ifneq ($(strip $(PKG_CAT)),)
+ # use existing PKG_CAT
+ UNPACK:=$(PKG_CAT) $(DL_DIR)/$(PKG_SOURCE) | tar -C $(PKG_BUILD_DIR)/.. $(TAR_OPTIONS) -
+ ifeq ($(PKG_CAT),unzip)
+ UNPACK=unzip -d $(PKG_BUILD_DIR) $(DL_DIR)/$(PKG_SOURCE)
+ endif
+ # replace zcat with $(ZCAT), because some system have it as gzcat
+ ifeq ($(PKG_CAT),zcat)
+ UNPACK:=$(ZCAT) $(DL_DIR)/$(PKG_SOURCE) | tar -C $(PKG_BUILD_DIR)/.. $(TAR_OPTIONS) -
+ endif
+ else
+ # try to autodetect file type
+ endif
+endif