[image] Fail "imgexec"/"boot" if the image to execute is ambiguous

If there is more than one loaded image, refuse to automatically select
the image to execute.  There are at least two possible cases, with
different "correct" answers:

1. User loads image A by mistake, then loads image B and types "boot".
   User wants to execute image B.

2. User loads image A, then loads image B (which patches image A), then
   types "boot".  User wants to execute image A.

If a user actually wants to load multiple images, they must explicitly
specify which image is to be executed.

diff --git a/src/hci/commands/image_cmd.c b/src/hci/commands/image_cmd.c
index 05e7dde..d1a38c4 100644 (file)
--- a/src/hci/commands/image_cmd.c
+++ b/src/hci/commands/image_cmd.c
@@ -407,7 +407,7 @@ static int imgexec_exec ( int argc, char **argv ) {
        } else {
                image = imgautoselect();
                if ( ! image ) {
-                       printf ( "No loaded images\n" );
+                       printf ( "No (unique) loaded image\n" );
                        return 1;
                }
        }

diff --git a/src/usr/imgmgmt.c b/src/usr/imgmgmt.c
index bead486..be153f8 100644 (file)
--- a/src/usr/imgmgmt.c
+++ b/src/usr/imgmgmt.c
@@ -86,19 +86,23 @@ int imgexec ( struct image *image ) {
 }
 
 /**
- * Identify the first loaded image
+ * Identify the only loaded image
  *
- * @ret image          Image, or NULL
+ * @ret image          Image, or NULL if 0 or >1 images are loaded
  */
 struct image * imgautoselect ( void ) {
        struct image *image;
+       struct image *selected_image = NULL;
+       int flagged_images = 0;
 
        for_each_image ( image ) {
-               if ( image->flags & IMAGE_LOADED )
-                       return image;
+               if ( image->flags & IMAGE_LOADED ) {
+                       selected_image = image;
+                       flagged_images++;
+               }
        }
 
-       return NULL;
+       return ( ( flagged_images == 1 ) ? selected_image : NULL );
 }
 
 /**