feat: add genimage finalize plugin

this allows projects to build more advanced filesystem and flash images
out of the oci images

see https://github.com/pengutronix/genimage

finalize-plugins/genimage.go

@@ -0,0 +1,90 @@
+package main
+
+import (
+	"C"
+	"encoding/json"
+	"fmt"
+	"github.com/vanilla-os/vib/api"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+type Genimage struct {
+	Name         string `json:"name"`
+	Type         string `json:"type"`
+	GenimagePath string `json:"genimagepath"`
+	Config       string `json:"config"`
+	Rootpath     string `json:"rootpath"`
+	Inputpath    string `json:"inputpath"`
+	Outputpath   string `json:"outputpath"`
+}
+
+//export PlugInfo
+func PlugInfo() *C.char {
+	plugininfo := &api.PluginInfo{Name: "genimage", Type: api.FinalizePlugin}
+	pluginjson, err := json.Marshal(plugininfo)
+	if err != nil {
+		return C.CString(fmt.Sprintf("ERROR: %s", err.Error()))
+	}
+	return C.CString(string(pluginjson))
+}
+
+//export PluginScope
+func PluginScope() int32 { // int32 is defined as GoInt32 in cgo which is the same as a C int
+	return api.IMAGENAME | api.FS | api.RECIPE
+}
+
+func ParsePath(path string, data *api.ScopeData) string {
+	path = strings.Replace(path, "$PROJROOT", data.Recipe.ParentPath, 1)
+	path = strings.Replace(path, "$FSROOT", data.FS, 1)
+	return path
+}
+
+//export FinalizeBuild
+func FinalizeBuild(moduleInterface *C.char, extraData *C.char) *C.char {
+	var module *Genimage
+	var data *api.ScopeData
+
+	err := json.Unmarshal([]byte(C.GoString(moduleInterface)), &module)
+	if err != nil {
+		return C.CString(fmt.Sprintf("ERROR: %s", err.Error()))
+	}
+
+	err = json.Unmarshal([]byte(C.GoString(extraData)), &data)
+	if err != nil {
+		return C.CString(fmt.Sprintf("ERROR: %s", err.Error()))
+	}
+
+	genimage := module.GenimagePath
+	if genimage == "" {
+		genimage, err = exec.LookPath("genimage")
+		if err != nil {
+			return C.CString(fmt.Sprintf("ERROR: %s", err.Error()))
+		}
+	}
+
+	cmd := exec.Command(
+		genimage,
+		"--config",
+		ParsePath(module.Config, data),
+		"--rootpath",
+		ParsePath(module.Rootpath, data),
+		"--outputpath",
+		ParsePath(module.Outputpath, data),
+		"--inputpath",
+		ParsePath(module.Inputpath, data),
+	)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Dir = data.Recipe.ParentPath
+
+	err = cmd.Run()
+	if err != nil {
+		return C.CString(fmt.Sprintf("ERROR: %s", err.Error()))
+	}
+
+	return C.CString("")
+}
+
+func main() {}