[OSSTEST PATCH 20/28] ts-debian-hvm-install: Cope with images containing only isolinux

[Ian Jackson <ian.jackson@eu.citrix.com>]

debian-7.2.0-i386-CD-1.iso contains no grub, only isolinux.

If the specified EFI grub file does not exist, fall back to isolinux.
This requires a -c option as well, according to
  https://wiki.debian.org/DebianInstaller/Modify/CD

Only try to set up a grub config if we are booting grub.  (The i386
image in question does not contain a [debian]/boot/grub directory.)

If boot/grub/efi.img _does_ exist (ie, for other existing tests), the
only difference in behaviour is to reorder slightly the options to
genisoimage: `-b boot/grub/efi.img' now occurs after `-no-emul-boot
-r' rather than before.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
---
v4: Log $bootfile value.
    Preseed generation now happens later due to previous patch;
      so $bootfile setting now also deferred.  Context change only.
---
 ts-debian-hvm-install |   12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/ts-debian-hvm-install b/ts-debian-hvm-install
index bb79d59..5197f9b 100755
--- a/ts-debian-hvm-install
+++ b/ts-debian-hvm-install
@@ -197,7 +197,6 @@ sub prep () {
     my $preseed_file_path = $base . "preseed";
 
     my @isogen_extra = qw(-eltorito-alt-boot
-                          -b boot/grub/efi.img
                           -no-emul-boot
                           -r);
 
@@ -222,6 +221,14 @@ sub prep () {
         my $cmds = iso_copy_content_from_image($gho, $newiso);
         target_cmd_root($ho, $cmds, $isotimeout);
 
+        my $bootfile = 'boot/grub/efi.img';
+        if (!target_file_exists($ho, "$newiso/$bootfile")) {
+            $bootfile = "isolinux/isolinux.bin";
+            push @isogen_extra, qw(-c isolinux/boot.cat);
+        }
+        logm("using boot image $bootfile");
+        push @isogen_extra, '-b', $bootfile;
+
         my @isogen_opts = (iso_gen_flags_basic(), @isogen_extra);
 
         target_putfilecontents_root_stash($ho, 10, preseed(),
@@ -231,7 +238,8 @@ sub prep () {
         target_cmd_root($ho, $cmds, $isotimeout);
 
         target_putfilecontents_root_stash($ho, 10, grub_cfg(),
-                                          "$newiso/debian/boot/grub/grub.cfg");
+                                          "$newiso/debian/boot/grub/grub.cfg")
+	    if $bootfile =~ m/grub/;
 
         target_putfilecontents_root_stash($ho, 10, isolinux_cfg(),
                                           "$newiso/isolinux/isolinux.cfg");
-- 
1.7.10.4