From: Richard Levitte <levitte@openssl.org>
Date: Fri, 6 Mar 2015 02:00:53 +0000 (+0100)
Subject: Add template reference processing.
X-Git-Tag: OpenSSL_1_1_0-pre1~1535
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=09816a2e339642e09c612ec48dde0754fec930d2;p=openssl

Add template reference processing.

Template references are words with double brackets, and refer to the
same field in the target pointed at the the double bracketed word.

For example, if a target's configuration has the following entry:

    'cflags' => '-DFOO {{x86_debug}}'

... then {{x86_debug}} will be replaced with the 'cflags' value from
target 'x86_debug'.

Note: template references are resolved recursively, and circular
references are not allowed

Reviewed-by: Andy Polyakov <appro@openssl.org>
---

diff --git a/Configure b/Configure
index ed1e9859b2..481eeabbab 100755
--- a/Configure
+++ b/Configure
@@ -304,6 +304,31 @@ sub stringtohash {
     return { map { shift @stringsequence => $_ } split /:/, $in };
 };
 
+# Support function to look for and resolve template references.
+# It uses breadcrumbs to check for circular template references.
+#
+# Note: Any configuration value is also a template.
+sub lookup_templates {
+    my $tableref = shift;
+    my $target = shift;
+    my @breadcrumbs = @_;
+
+    if (grep { $_ eq $target } @breadcrumbs) {
+	die "Template loop!  target backtrace:\n  ",join("\n  ",
+							 $target,
+							 @breadcrumbs),"\n";
+    }
+
+    foreach my $key (keys %{$tableref->{$target}}) {
+	my $value = $tableref->{$target}->{$key};
+	while ($value =~ /{{([-\w]+)}}/) {
+	    lookup_templates($tableref, $1, $target, @breadcrumbs);
+	    $value = $`.$tableref->{$1}->{$key}.$';
+	}
+	$tableref->{$target}->{$key} = $value;
+    }
+};
+
 
 # Read configuration target stanzas from a file, so that people can have
 # local files with their own definitions
@@ -445,6 +470,11 @@ sub read_config {
 	}
 
 	%table = (%table, %targets);
+
+	# Go through all new targets and resolve template references.
+	foreach (keys %targets) {
+	    lookup_templates(\%table, $_);
+	}
 }
 
 my ($vol, $dir, $dummy) = File::Spec->splitpath($0);