dist/tools: add desvirt (incl. example topology)

dist/tools/desvirt/.gitignore

+/desvirt

dist/tools/desvirt/Makefile

+PKG_NAME=desvirt
+PKG_URL=https://github.com/des-testbed/desvirt.git
+PKG_VERSION=master
+PKG_DIR=$(CURDIR)/$(PKG_NAME)
+
+.PHONY: all clean patch distclean desvirtdefine
+
+all: clean $(PKG_NAME) patch desvirtdefine
+
+patch:
+	cd "$(PKG_DIR)" && git am --ignore-whitespace "$(CURDIR)"/*.patch
+
+desvirtdefine: patch
+	$(foreach topology,$(shell ls $(PKG_NAME)/.desvirt/*.xml), \
+		cd $(PKG_NAME) && \
+		./vnet --define --name "$(basename $(notdir $(topology)))";)
+
+$(PKG_NAME):
+	# Get $(PKG_VERSION) of package from $(PKG_URL)
+	$(if $(wildcard $(PKG_NAME)),cd $(CURDIR)/$(PKG_NAME) && \
+		git clean -x -f && \
+		git reset --hard $(PKG_VERSION) \
+		, git clone $(PKG_URL) $(PKG_NAME) && \
+		cd $(PKG_NAME) && \
+		git reset --hard $(PKG_VERSION))
+
+clean::
+	# Reset package to checkout state.
+	$(if $(wildcard $(PKG_NAME)),cd $(CURDIR)/$(PKG_NAME) && \
+		git clean -x -f && \
+		git reset --hard $(PKG_VERSION) \
+		, )
+
+distclean::
+	rm -rf $(CURDIR)/$(PKG_NAME)