rootfs make target (#1333)

New makefile target to create rootfs.vhd from rootfs.tar using tar2ext4.
Requires building cmd/tar2ext4 locally.

Signed-off-by: Hamza El-Saawy <hamzaelsaawy@microsoft.com>

.gitignore

@@ -6,6 +6,7 @@
 
 # Ignore vscode setting files
 .vscode/
+.idea/
 
 # Test binary, build with `go test -c`
 *.test
@@ -28,11 +29,9 @@ service/pkg/
 .rootfs-done
 bin/*
 rootfs/*
+rootfs-conv/*
 *.o
 /build/
 
 deps/*
-out/*
-
-.idea/
-.vscode/
+out/*

Makefile

@@ -23,6 +23,8 @@ GCS_TOOLS=\
 
 .PHONY: all always rootfs test
 
+.DEFAULT_GOAL := all
+
 all: out/initrd.img out/rootfs.tar.gz
 
 clean:
@@ -32,6 +34,12 @@ clean:
 test:
 	cd $(SRCROOT) && go test -v ./internal/guest/...
 
+rootfs: out/rootfs.vhd
+
+out/rootfs.vhd: out/rootfs.tar.gz bin/cmd/tar2ext4
+	gzip -f -d ./out/rootfs.tar.gz
+	bin/cmd/tar2ext4 -vhd -i ./out/rootfs.tar -o $@
+
 out/delta.tar.gz: bin/init bin/vsockexec bin/cmd/gcs bin/cmd/gcstools bin/cmd/hooks/wait-paths Makefile
 	@mkdir -p out
 	rm -rf rootfs
@@ -62,6 +70,7 @@ out/initrd.img: $(BASE) out/delta.tar.gz $(SRCROOT)/hack/catcpio.sh
 -include deps/cmd/gcs.gomake
 -include deps/cmd/gcstools.gomake
 -include deps/cmd/hooks/wait-paths.gomake
+-include deps/cmd/tar2ext4.gomake
 
 # Implicit rule for includes that define Go targets.
 %.gomake: $(SRCROOT)/Makefile