Fix pygrub handling of many kernels

If there are a large number of kernel images configured in grub.conf
there will be too many to fit in the limited size pygrub display. This
patch fixes this so that the list of kernels scrolls as needed.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

1 files changed, 12 insertions, 4 deletions

diff --git a/tools/pygrub/src/pygrub b/tools/pygrub/src/pygrub
index 22b2707c5c..51a4220647 100644
--- a/tools/pygrub/src/pygrub
+++ b/tools/pygrub/src/pygrub
@@ -27,7 +27,7 @@ import fsimage
 import grub.GrubConf
 import grub.LiloConf
 
-PYGRUB_VER = 0.5
+PYGRUB_VER = 0.6
 
 def enable_cursor(ison):
     if ison:
@@ -228,15 +228,22 @@ class Grub:
     def fill_entry_list(self):
         self.entry_win.clear()
         self.entry_win.box()
-        for y in range(0, len(self.cf.images)):
+
+        maxy = self.entry_win.getmaxyx()[0]-3 # maxy - 2 for the frame + index
+        if self.selected_image > self.start_image + maxy:
+            self.start_image = self.selected_image
+        if self.selected_image < self.start_image:
+            self.start_image = self.selected_image
+        
+        for y in range(self.start_image, len(self.cf.images)):
             i = self.cf.images[y]
-            if (0, y) > self.entry_win.getmaxyx():
+            if y > self.start_image + maxy:
                 break
             if y == self.selected_image:
                 attr = curses.A_REVERSE
             else:
                 attr = 0
-            self.entry_win.addstr(y + 1, 2, i.title.ljust(70), attr)
+            self.entry_win.addstr(y + 1 - self.start_image, 2, i.title.ljust(70), attr)
         self.entry_win.refresh()
 
     def edit_entry(self, origimg):
@@ -416,6 +423,7 @@ class Grub:
 
         # now loop until we hit the timeout or get a go from the user
         mytime = 0
+        self.start_image = 0
         while (timeout == -1 or mytime < int(timeout)):
             draw()
             if timeout != -1 and mytime != -1: