Scripts temporarily deregister themselves while executing. This

allows us to avoid execution loops without having to hack around the
image registration order.

src/core/image.c

@@ -106,20 +106,6 @@ void unregister_image ( struct image *image ) {
 	DBGC ( image, "IMAGE %p unregistered\n", image );
 }
 
-/**
- * Move image to start of list of registered images
- *
- * @v image		Executable/loadable image
- *
- * Move the image to the start of the image list.  This makes it
- * easier to keep track of which of the images marked as loaded is
- * likely to still be valid.
- */
-void promote_image ( struct image *image ) {
-	list_del ( &image->list );
-	list_add ( &image->list, &images );
-}
-
 /**
  * Find image by name
  *

src/image/script.c

@@ -44,6 +44,13 @@ static int script_exec ( struct image *image ) {
 	char *eol;
 	int rc;
 
+	/* Temporarily de-register image, so that a "boot" command
+	 * doesn't throw us into an execution loop.  Hold a reference
+	 * to avoid the image's being freed.
+	 */
+	image_get ( image );
+	unregister_image ( image );
+
 	while ( offset < image->len ) {
 	
 		/* Read up to cmdbuf bytes from script into buffer */
@@ -60,7 +67,8 @@ static int script_exec ( struct image *image ) {
 		if ( ! eol ) {
 			DBG ( "Script line too long (max %d bytes)\n",
 			      sizeof ( cmdbuf ) );
-			return -ENOEXEC;
+			rc = -ENOEXEC;
+			goto done;
 		}
 
 		/* Mark end of line and execute command */
@@ -69,14 +77,19 @@ static int script_exec ( struct image *image ) {
 		if ( ( rc = system ( cmdbuf ) ) != 0 ) {
 			DBG ( "Command \"%s\" exited with status %d\n",
 			      cmdbuf, rc );
-			return rc;
+			goto done;
 		}
 		
 		/* Move to next line */
 		offset += ( ( eol - cmdbuf ) + 1 );
 	}
 
-	return 0;
+	rc = 0;
+ done:
+	/* Re-register image and return */
+	register_image ( image );
+	image_put ( image );
+	return rc;
 }
 
 /**

src/usr/imgmgmt.c

@@ -89,7 +89,8 @@ int imgload ( struct image *image ) {
 		return rc;
 
 	/* If we succeed, move the image to the start of the list */
-	promote_image ( image );
+#warning "No longer exists"
+	//	promote_image ( image );
 
 	return 0;
 }