Description: Guard against scripts containing no commands
 Make grub-script-check fail on scripts containing no commands, to guard
 against corrupted grub-mkconfig setups that produce no useful output.
Origin: backport, http://bazaar.launchpad.net/~vcs-imports/grub/grub2-bzr/revision/5044
Author: Colin Watson <cjwatson@debian.org>
Bug-Debian: http://bugs.debian.org/713886
Forwarded: not-needed
Last-Update: 2013-06-25

Index: b/Makefile.util.def
===================================================================
--- a/Makefile.util.def
+++ b/Makefile.util.def
@@ -701,6 +701,12 @@
 
 script = {
   testcase;
+  name = grub_script_no_commands;
+  common = tests/grub_script_no_commands.in;
+};
+
+script = {
+  testcase;
   name = partmap_test;
   common = tests/partmap_test.in;
 };
Index: b/tests/grub_script_no_commands.in
===================================================================
--- /dev/null
+++ b/tests/grub_script_no_commands.in
@@ -0,0 +1,21 @@
+#! /bin/sh
+set -e
+
+# grub-script-check refuses to pass a file with no commands; this usually
+# indicates a bug in the code generating that file.
+
+@builddir@/grub-script-check <<EOF && exit 1
+
+EOF
+
+@builddir@/grub-script-check <<EOF && exit 1
+# comment
+EOF
+
+@builddir@/grub-script-check <<EOF && exit 1
+# comment 1
+# comment 2
+
+EOF
+
+exit 0
Index: b/util/grub-script-check.c
===================================================================
--- a/util/grub-script-check.c
+++ b/util/grub-script-check.c
@@ -92,7 +92,7 @@
   int lineno = 0;
   FILE *file = 0;
   struct arguments arguments;
-  int found_input = 0;
+  int found_input = 0, found_cmd = 0;
   struct grub_script *script = NULL;
 
   auto grub_err_t get_config_line (char **line, int cont);
@@ -177,6 +177,8 @@
       script = grub_script_parse (input, get_config_line);
       if (script)
 	{
+	  if (script->cmd)
+	    found_cmd = 1;
 	  grub_script_execute (script);
 	  grub_script_free (script);
 	}
@@ -191,6 +193,12 @@
       fprintf (stderr, _("Syntax error at line %u\n"), lineno);
       return 1;
     }
+  if (! found_cmd)
+    {
+      fprintf (stderr, _("Script contains no commands and will do nothing\n"),
+	       ctx.arguments.filename);
+      return 1;
+    }
 
   return 0;
 }