hacking: add make vmoverlay for faster hacking

For the regular hack/build/test cycles, creating a new deployment each
time becomes overkill. We add a new `make vmoverlay` target which
directly overlays the newly built binaries on an unlocked system.

We also make rsync smarter so that we can afford to not `make clean`
everytime while still allowing the host's repo to be fully configured.

Closes: #360
Approved by: cgwalters

HACKING.md

@@ -38,13 +38,22 @@ container). We're hoping to improve this workflow soon.
 Hacking
 =======
 
-The `make vmbuild` command will automatically sync the
-current files to the VM, build `rpm-ostree` and install it
-into a new deployment, and finally reboot the VM to use it.
+The `make vmoverlay` command will automatically sync the
+current files to the VM, unlock the current deployment,
+build `rpm-ostree`, and install it.
+
+If you need to test on a locked deployment with the updated
+`rpm-ostree` baked into the tree, you can use the `make
+vmbuild` command, which will install `rpm-ostree` into a new
+deployment and reboot the VM to use it.
 
 For convenience, the `make vmshell` command does the same
-but additionally places you in a shell, ready to test your
-changes.
+as `make vmbuild` but additionally places you in a shell,
+ready to test your changes.
+
+Note that by default, all the commands above try to re-use
+the same configuration files to save speed. If you want to
+force a cleanup, you can use `VMCLEAN=1`.
 
 Testing
 =======

Makefile-tests.am

@@ -85,6 +85,7 @@ check-local:
 vmbuild:
 	@if [ -z "$(SKIP_VMBUILD)" ]; then \
 	  vagrant up && \
+	  ( [ -z "$(VMCLEAN)" ] || vagrant ssh -c "rm -rf sync" ) && \
 	  vagrant rsync && \
 	  vagrant ssh -c "cd sync/vagrant && \
 	                  make install VERSION=$$(git describe)" && \
@@ -92,6 +93,14 @@ vmbuild:
 	  sleep 2; \
 	fi
 
+vmoverlay:
+	vagrant up && \
+	( [ -z "$(VMCLEAN)" ] || vagrant ssh -c "rm -rf sync" ) && \
+	vagrant rsync && \
+	vagrant ssh -c "cd sync/vagrant && make ofsinstall" && \
+	vagrant ssh -c "systemctl daemon-reload && \
+	                systemctl restart rpm-ostreed"
+
 vmshell: vmbuild
 	vagrant ssh
 

Vagrantfile

@@ -21,7 +21,12 @@ Vagrant.configure(2) do |config|
     # containers)
     config.vm.synced_folder ".", "/home/vagrant/sync", disabled: true
     config.vm.synced_folder ".", "/root/sync", type: "rsync",
-      rsync__exclude: [".git/", "vagrant/*.tar.gz"]
+      rsync__exclude: [".git/", "vagrant/*.tar.gz"],
+
+      # override the default args so that
+      #  (1) we don't use --delete (otherwise we will have to regen each time)
+      #  (2) we can tell rsync to skip ignored files
+      rsync__args: ["--verbose", "--archive", "-z", "--filter", ":- .gitignore"]
 
     config.vm.provider "libvirt" do |libvirt, override|
       libvirt.cpus = 2

vagrant/Makefile

@@ -10,8 +10,13 @@ buildimg:
 	sudo docker build -t $(BUILDER_IMG) -f Dockerfile.builder .
 
 build:
-	$(BUILDER_RUN) ./autogen.sh --prefix=/usr --libdir=/usr/lib64
-	$(BUILDER_RUN) sh -c 'make clean && make -j 4'
+	if ! test -f ../configure; then \
+	  $(BUILDER_RUN) env NOCONFIGURE=1 ./autogen.sh; \
+	fi
+	if ! test -f ../Makefile; then \
+	  $(BUILDER_RUN) ./configure --prefix=/usr --libdir=/usr/lib64; \
+	fi
+	$(BUILDER_RUN) sh -c make -j 4
 
 install: build
 	sudo sh checkout.sh
@@ -19,3 +24,9 @@ install: build
 	                -v /ostree/repo/tmp/vmcheck.ro/usr:/host/usr \
 	                $(BUILDER_IMG) sudo make install DESTDIR=/host
 	sudo VERSION=$(VERSION) sh commit_and_deploy.sh
+
+ofsinstall: build
+	ostree admin unlock || :
+	$(BUILDER_ARGS) -v /etc:/host/etc \
+	                -v /usr:/host/usr \
+	                $(BUILDER_IMG) sudo make install DESTDIR=/host