build: Update make_kconfig to support depends on in menus

From: Trent Piepho <xyzzy@speakeasy.org>

A backported kernel patch added a "depends on" clause to a menu, which wasn't
yet handled.

Everything in a menu gains implicitly gains a copy of the menu's dependencies
We handle this the same way as if/endif is handled.  It may not work properly
if someone makes a nonsense file like:
menu "foo"
if X
endmenu
endif

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>

1 files changed, 21 insertions, 4 deletions

diff --git a/v4l/scripts/make_kconfig.pl b/v4l/scripts/make_kconfig.pl
index 5e9e416d1..3bfc26a18 100755
--- a/v4l/scripts/make_kconfig.pl
+++ b/v4l/scripts/make_kconfig.pl
@@ -219,6 +219,7 @@ sub checkdeps()
 		my $key = shift;
 		my $deps = $depends{$key};
 		foreach (@$deps) {
+			next if($_ eq '');
 			if (!eval(toperl($_))) {
 				print "Disabling $key, dependency '$_' not met\n" if $debug;
 				$allconfig{$key} = 0;
@@ -343,10 +344,13 @@ sub open_kconfig($$) {
 			$key = 'comment';
 		} elsif (m|^\s*menu\s+"[^"]*"\s*$|) {
 			$key = 'menu';
+			push @kifs, '';  # placeholder for any depends on clauses
 		} elsif (m|^\s*if\s+(.+?)\s*$|) {
 			push @kifs, $1;
-		} elsif (m|^\s*endif\s*(?:#.*)?$|) {
-			$#kifs >= 0 or die "Unmatched endif at $file:$.\n";
+		} elsif (/^\s*end(if|menu)\s*(?:#.*)?$/) {
+			# Won't handle menu/if blocks that aren't strictly
+			# nested, but no one should do that!
+			$#kifs >= 0 or die "Unmatched end$1 at $file:$.\n";
 			pop @kifs;
 		} else {
 			$nothandled = 1;
@@ -358,8 +362,21 @@ sub open_kconfig($$) {
 			next;
 		}
 
-		# Don't process any directives in comment blocks (or menus)
-		next if ($key eq 'comment' || $key eq 'menu');
+		# Don't process any directives in comment blocks
+		next if ($key eq 'comment');
+
+		# Only depends on lines are accepted in menus
+		if ($key eq 'menu') {
+			if (m|^\s*depends on\s+(.+?)\s*$|) {
+			    my $x = pop @kifs;
+			    $x .= ' && ' if($x ne '');
+			    $x .= "($1)";
+			    push @kifs, $x;
+			} else {
+			    print "Skipping unexpected line in menu stanza $file:$.$_" if $debug;
+			}
+			next;
+		}
 
 		# config type
 		if(/^\s*bool(ean)?\s/) {