ukify: stop appending NUL to merged .sbat section

Our tools will strip trailing NULs, so this is not causing harm, except for
the corner case when the .sbat section is exactly of the maximum size and now
it wouldn't fit because we're one byte short.

But it also is not needed. Sections have an encoded size of the data and the
reader must use that and must be prepared to handle a text section that does
not end in NUL. Appending of the NUL was added in
c3f7501c4d014482b17988d5aed1d88127a50b6e, without any discussion of this
change. Since we didn't insert the NUL before, the tools must have been
prepared to work without it. I think it's better to keep the code clean and
not do this unnecessary step.

diff --git a/src/ukify/ukify.py b/src/ukify/ukify.py
index e3c427166d302ba4cba390140d5b9c29289d3a22..c034befd85f628f272fd8a7c2ae265ceedde6ec4 100755 (executable)
--- a/src/ukify/ukify.py
+++ b/src/ukify/ukify.py
@@ -1150,10 +1150,12 @@ def merge_sbat(input_pe: list[Path], input_text: list[str]) -> str:
             continue
         sbat += split[1:]
 
-    return (
-        'sbat,1,SBAT Version,sbat,1,https://github.com/rhboot/shim/blob/main/SBAT.md\n'
-        + '\n'.join(sbat)
-        + '\n\x00'
+    return '\n'.join(
+        (
+            'sbat,1,SBAT Version,sbat,1,https://github.com/rhboot/shim/blob/main/SBAT.md',
+            *sbat,
+            '',  # an empty line so that we end up with a newline at the end
+        )
     )