shimv2: Add a "--version" cli option

All components should support a `--version` option to allow clear
identification of the version of the component being used.

Note that the build changes are required to allow the shim binary to
access the golang code generated by the build
(such as the `version` variable).

Fixes: #2886.

Signed-off-by: James O. D. Hunt <james.o.hunt@intel.com>

Makefile

@@ -718,6 +718,7 @@ clean:
 		$(GENERATED_FILES) \
 		$(NETMON_TARGET) \
 		$(SHIMV2) \
+		$(SHIMV2_DIR)/$(notdir $(GENERATED_CONFIG)) \
 		$(TARGET) \
 		.git-commit .git-commit.tmp
 

cli/containerd-shim-kata-v2/main.go

@@ -6,15 +6,25 @@
 package main
 
 import (
+	"fmt"
+	"os"
+
 	"github.com/containerd/containerd/runtime/v2/shim"
 	"github.com/kata-containers/runtime/containerd-shim-v2"
 )
 
+const shimID = "io.containerd.kata.v2"
+
 func shimConfig(config *shim.Config) {
 	config.NoReaper = true
 	config.NoSubreaper = true
 }
 
 func main() {
-	shim.Run("io.containerd.kata.v2", containerdshim.New, shimConfig)
+	if len(os.Args) == 2 && os.Args[1] == "--version" {
+		fmt.Printf("%s containerd shim: id: %q, version: %s, commit: %v\n", project, shimID, version, commit)
+		os.Exit(0)
+	}
+
+	shim.Run(shimID, containerdshim.New, shimConfig)
 }