feat: Add the stop/start loop for the service

sdk/lib/types.ts

@@ -276,7 +276,13 @@ export type Effects = {
   }): Promise<unknown>
 
   /** A low level api used by makeOverlay */
-  createOverlayedImage(options: { imageId: string }): Promise<string>
+  createOverlayedImage(options: { imageId: string }): Promise<[string, string]>
+
+  /** A low level api used by destroyOverlay + makeOverlay:destroy */
+  destroyOverlayedImage(options: {
+    imageId: string
+    guid: string
+  }): Promise<void>
 
   /** Removes all network bindings */
   clearBindings(): Promise<void>

sdk/lib/util/Overlay.ts

@@ -10,9 +10,10 @@ export class Overlay {
     readonly effects: T.Effects,
     readonly imageId: string,
     readonly rootfs: string,
+    readonly guid: string,
   ) {}
   static async of(effects: T.Effects, imageId: string) {
-    const rootfs = await effects.createOverlayedImage({ imageId })
+    const [rootfs, guid] = await effects.createOverlayedImage({ imageId })
 
     for (const dirPart of ["dev", "sys", "proc", "run"] as const) {
       await fs.mkdir(`${rootfs}/${dirPart}`, { recursive: true })
@@ -23,7 +24,7 @@ export class Overlay {
       ])
     }
 
-    return new Overlay(effects, imageId, rootfs)
+    return new Overlay(effects, imageId, rootfs, guid)
   }
 
   async mount(options: MountOptions, path: string): Promise<Overlay> {
@@ -51,8 +52,9 @@ export class Overlay {
   }
 
   async destroy() {
-    await execFile("umount", ["-R", this.rootfs])
-    await fs.rm(this.rootfs, { recursive: true, force: true })
+    const imageId = this.imageId
+    const guid = this.guid
+    await this.effects.destroyOverlayedImage({ imageId, guid })
   }
 
   async exec(

sdk/lib/util/utils.ts

@@ -246,7 +246,7 @@ export const createUtils = <
           console.error(data.toString())
         })
 
-        childProcess.on("close", (code: any) => {
+        childProcess.on("exit", (code: any) => {
           if (code === 0) {
             return resolve(null)
           }
@@ -262,7 +262,7 @@ export const createUtils = <
           try {
             childProcess.kill(signal)
 
-            if (timeout <= NO_TIMEOUT) {
+            if (timeout > NO_TIMEOUT) {
               const didTimeout = await Promise.race([
                 new Promise((resolve) => setTimeout(resolve, timeout)).then(
                   () => true,
@@ -270,6 +270,7 @@ export const createUtils = <
                 answer.then(() => false),
               ])
               if (didTimeout) childProcess.kill(SIGKILL)
+              return
             }
             await answer
           } finally {