[OSSTEST Nested PATCH v11 2/7] Parsing grub which has 'submenu' primitive

["longtao.pang" <longtaox.pang@intel.com>]

Now auto-gen kernel grub2 config file's boot menu entries can have
2-level hierarchy, containing 'submenu' primitive, which is comprised by
several sub-menuentries. Xen boot entries are grouped into such kind of
'submenu' block. This patch adds setupboot_grub2() ability to handle
such new grub.cfg format

Signed-off-by: longtao.pang <longtaox.pang@intel.com>
---
Changes in v11:
1. Ian corrects our previous implementation of submenu handling. When
selecting submenu's menuentry, it shall be the 2-level format of 'M>N',
M is the 'submenu' entry number in first level, N is the sub-menuentry
numbering inside 'submenu' block, starting from 0.
Ian's correcting patch:
http://lists.xenproject.org/archives/html/xen-devel/2015-05/msg03108.html.
Based on Ian's correcting patch, we dogmatically alternatively use
'pop/push' to handle array of @offsets.
---
 Osstest/Debian.pm |   24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/Osstest/Debian.pm b/Osstest/Debian.pm
index 46388d8..b1d1043 100644
--- a/Osstest/Debian.pm
+++ b/Osstest/Debian.pm
@@ -405,12 +405,22 @@ sub setupboot_grub2 ($$$$) {
     my $parsemenu= sub {
         my $f= bl_getmenu_open($ho, $rmenu, "$stash/$ho->{Name}--grub.cfg.1");
     
-        my $count= 0;
+        my @offsets = (0);
         my $entry;
+        my $submenu;
         while (<$f>) {
             next if m/^\s*\#/ || !m/\S/;
             if (m/^\s*\}\s*$/) {
-                die unless $entry;
+                die unless $entry || $submenu;
+                if(!defined $entry && defined $submenu){
+                    logm("Met end of a submenu starting from ".
+                        "$submenu->{StartLine}. ".
+                        "Our want kern is $want_kernver");
+                    $submenu=undef;
+                    pop @offsets;
+                    $offsets[$#offsets]++;
+                    next;
+                }
                 my (@missing) =
                     grep { !defined $entry->{$_} } 
 		        (defined $xenhopt
@@ -438,8 +448,12 @@ sub setupboot_grub2 ($$$$) {
             }
             if (m/^menuentry\s+[\'\"](.*)[\'\"].*\{\s*$/) {
                 die $entry->{StartLine} if $entry;
-                $entry= { Title => $1, StartLine => $., Number => $count };
-                $count++;
+                $entry= { Title => $1, StartLine => $., MenuEntryPath => join ">", @offsets };
+                $offsets[$#offsets]++;
+            }
+            if (m/^submenu\s+[\'\"](.*)[\'\"].*\{\s*$/) {
+                $submenu={ StartLine =>$., MenuEntryPath => join ">", @offsets };
+                push @offsets,(0);
             }
             if (m/^\s*multiboot\s*\/(xen\-[0-9][-+.0-9a-z]*\S+)/) {
                 die unless $entry;
@@ -500,7 +514,7 @@ sub setupboot_grub2 ($$$$) {
             }
             print ::EO <<END or die $!;
 
-GRUB_DEFAULT=$entry->{Number}
+GRUB_DEFAULT="$entry->{MenuEntryPath}"
 END
 
             print ::EO <<END or die $! if defined $xenhopt;
-- 
1.7.10.4