Allow space for a bootloader installed with dd

Implement bootoffset to explcitly allow space for
a bootloader to be installed in front of the
first partition. Add support for cubietruck in
the example to dd the Debian uboot image by adding
a parameter to the customise script call.
Increase size of boot partition to make upgrades easier.
Allow the partition type to be specified.
Use mib units as these are converted to 1024 instead of 1000.

1 files changed, 32 insertions, 7 deletions

diff --git a/vmdebootstrap b/vmdebootstrap
index aae437a..6f104da 100755
--- a/vmdebootstrap
+++ b/vmdebootstrap
@@ -292,17 +292,41 @@ class VmDebootstrap(cliapp.Application):  # pylint: disable=too-many-public-meth
                      str(self.settings['size'])])
 
     def partition_image(self):
+        """
+        Uses fat16 (msdos) partitioning by default, use part-type to change.
+        If bootoffset is specified, the first actual partition
+        starts at that offset to allow customisation scripts to
+        put bootloader images into the space, e.g. u-boot.
+        """
         self.message('Creating partitions')
         self.runcmd(['parted', '-s', self.settings['image'],
-                     'mklabel', 'msdos'])
+                     'mklabel', self.settings['part-type']])
+        partoffset = 0
+        bootsize = 0
+        if self.settings['bootoffset'] and self.settings['bootoffset'] is not '0':
+            # turn v.small offsets into something at least possible to create.
+            if self.settings['bootoffset'] < 1048576:
+                partoffset = 1
+                logging.info(
+                    "Setting bootoffset %smib to allow for %s bytes",
+                    partoffset, self.settings['bootoffset'])
+            else:
+                partoffset = self.settings['bootoffset'] / (1024 * 1024)
+                self.message("Using bootoffset: %smib %s bytes" % (partoffset, self.settings['bootoffset']))
         if self.settings['bootsize'] and self.settings['bootsize'] is not '0%':
-            bootsize = str(self.settings['bootsize'] / (1024 * 1024))
+            bootsize = self.settings['bootsize'] / (1024 * 1024)
+            bootsize += partoffset
+            self.message("Using bootsize %smib: %s bytes" % (bootsize, self.settings['bootsize']))
+            logging.debug("Starting boot partition at %sMb", bootsize)
             self.runcmd(['parted', '-s', self.settings['image'],
-                         'mkpart', 'primary', 'fat16', '0%', bootsize])
+                         'mkpart', 'primary', 'fat16', str(partoffset), str(bootsize)])
+        if partoffset == 0:
+            self.runcmd(['parted', '-s', self.settings['image'],
+                         'mkpart', 'primary', '0%', '100%'])
         else:
-            bootsize = '0%'
-        self.runcmd(['parted', '-s', self.settings['image'],
-                     'mkpart', 'primary', bootsize, '100%'])
+            logging.debug("Starting root partition at %sMb", partoffset)
+            self.runcmd(['parted', '-s', self.settings['image'],
+                         'mkpart', 'primary', str(bootsize), '100%'])
         self.runcmd(['parted', '-s', self.settings['image'],
                      'set', '1', 'boot', 'on'])
 
@@ -662,8 +686,9 @@ append initrd=%(initrd)s root=UUID=%(uuid)s ro %(kserial)s
                 return
             script = example
         self.message('Running customize script %s' % script)
+        logging.info("rootdir=%s image=%s", rootdir, self.settings['image'])
         with open('/dev/tty', 'w') as tty:
-            cliapp.runcmd([script, rootdir], stdout=tty, stderr=tty)
+            cliapp.runcmd([script, rootdir, self.settings['image']], stdout=tty, stderr=tty)
 
     def create_tarball(self, rootdir):
         # Create a tarball of the disk's contents