Make bootloader installation for disk images optional

1 files changed, 20 insertions, 1 deletions

diff --git a/writeexts.py b/writeexts.py
index af48b375..23b876ae 100755
--- a/writeexts.py
+++ b/writeexts.py
@@ -65,7 +65,8 @@ class WriteExtension(cliapp.Application):
             self.create_factory(mp, temp_root)
             self.create_fstab(mp)
             self.create_factory_run(mp)
-            self.install_extlinux(mp)
+            if self.bootloader_is_wanted():
+                self.install_extlinux(mp)
         except BaseException, e:
             sys.stderr.write('Error creating disk image')
             self.unmount(mp)
@@ -212,3 +213,21 @@ class WriteExtension(cliapp.Application):
             return s.split(':')
         else:
             return []
+
+    def bootloader_is_wanted(self):
+        '''Does the user request a bootloader?
+
+        The user may set $BOOTLOADER to yes, no, or auto. If not
+        set, auto is the default and means that the bootloader will
+        be installed on x86-32 and x86-64, but not otherwise.
+
+        '''
+
+        value = os.environ.get('BOOTLOADER', 'auto')
+        if value == 'auto':
+            if os.uname()[-1] in ['x86_32', 'x86_64']:
+                value = 'yes'
+            else:
+                value = 'no'
+
+        return value == 'yes'