Apply patch by Thorsten Glaser which prepares code for his future work

[grml2usb.git] / grml2usb

diff --git a/grml2usb b/grml2usb
index 7d67047..2bb5439 100755 (executable)
--- a/grml2usb
+++ b/grml2usb
@@ -88,6 +88,21 @@ class CriticalException(Exception):
     pass
 
 
+# The following two functions help to operate on strings as
+# array (list) of bytes (octets). In Python 3000, the bytes
+# datatype will need to be used. This is intended for using
+# with manipulation of files on the octet level, like shell
+# arrays, e.g. in MBR creation.
+
+def array2string(a):
+    """Convert a list of integers [0;255] to a string."""
+    return struct.pack("%sB" % len(a), *a)
+
+def string2array(s):
+    """Convert a (bytes) string into a list of integers."""
+    return struct.unpack("%sB" % len(s), s)
+
+
 def cleanup():
     """Cleanup function to make sure there aren't any mounted devices left behind.
     """
@@ -525,7 +540,7 @@ def generate_flavour_specific_syslinux_config(grml_flavour):
 
     return("""\
 menu begin grml %(grml_flavour)s
-    menu title Grml %(grml_flavour)s
+    menu title %(grml_flavour)s
     label mainmenu
     menu label ^Back to main menu...
     menu exit
@@ -1344,7 +1359,18 @@ def adjust_syslinux_bootoptions(src_name, dst_name, flavour):
 
 
 def add_syslinux_entry(filename, grml_flavour):
-    data = open(filename, "a")
+    data = open(filename, "a+")
+    entry_filename = "option-%s.cfg" % grml_flavour
+    entry = "include %s\n" % entry_filename
+    path = os.path.dirname(filename)
+    for line in data:
+        if line == entry:
+            break
+    else:
+        data.write(entry)
+
+    data.close()
+    data = open(path + "/" + entry_filename, "w")
     data.write(generate_flavour_specific_syslinux_config(grml_flavour))
     data.close()
 
@@ -1386,8 +1412,14 @@ def handle_syslinux_config(grml_flavour, target):
 
     new_hidden =  "%s-hidden.cfg" % (grml_flavour)
     new_default = "%s-default.cfg" % (grml_flavour)
-    default_file = open("%s/defaults.cfg" % syslinux_target, "a")
-    default_file.write("include %s\n" % new_default)
+    default_file = open("%s/defaults.cfg" % syslinux_target, "a+")
+    entry = "include %s\n" % new_default
+    for line in default_file:
+        if line == entry:
+            break
+    else:
+        default_file.write("include %s\n" % new_default)
+
     default_file.close()
     add_syslinux_entry("%s/additional.cfg" % syslinux_target, grml_flavour)