Ignore trailing whitespace in header guards

This is specifically needed to handle CRLF lines in Python2, otherwise
the regex for header guards does not match and building the
amalgamation fails.

This only occured if a header was edited on Windows then later a build
using amalgamation attempted on Linux.

Closes #1763

1 files changed, 3 insertions, 2 deletions

diff --git a/configure.py b/configure.py
index fc9a0ba2b..dc39c2541 100755
--- a/configure.py
+++ b/configure.py
@@ -2453,7 +2453,8 @@ class AmalgamationHeader(object):
 class AmalgamationGenerator(object):
     filename_prefix = 'botan_all'
 
-    _header_guard_pattern = re.compile('^#define BOTAN_.*_H_$')
+    _header_guard_pattern = re.compile(r'^#define BOTAN_.*_H_\s*$')
+    _header_endif_pattern = re.compile(r'^#endif\s*$')
 
     @staticmethod
     def read_header(filepath):
@@ -2478,7 +2479,7 @@ class AmalgamationGenerator(object):
 
         end_header_guard_index = None
         for index, line in enumerate(lines):
-            if line == '#endif\n':
+            if AmalgamationGenerator._header_endif_pattern.match(line):
                 end_header_guard_index = index # override with last found
         if end_header_guard_index is None:
             raise InternalError("No header guard end found in " + header_name)