Fix buildinf.h generation for space and backslash

Builds may be configured with CC or CFLAGS containing space and
double quotes. In particular on Windows, this may lead to passing
more than two arguments into mkbuildinf.pl.
In addition, backslashes must be escaped for constructing the C string.

Fixes #26253.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/26315)

diff --git a/util/mkbuildinf.pl b/util/mkbuildinf.pl
index 7b1aba054ccc937e59c1c85cfb8793119181f8a0..a892a4396f2a1a61c995356e8755a2f4cd7990c6 100755 (executable)
--- a/util/mkbuildinf.pl
+++ b/util/mkbuildinf.pl
@@ -9,7 +9,9 @@
 use strict;
 use warnings;
 
-my ($cflags, $platform) = @ARGV;
+my $platform = pop @ARGV;
+my $cflags = join(' ', @ARGV);
+$cflags =~ s(\\)(\\\\)g;
 $cflags = "compiler: $cflags";
 
 # Use the value of the envvar SOURCE_DATE_EPOCH, even if it's