sbox2: Add pre-processor token support to gen-interface.

This adds support for pre-processor tokens in interface.master,
the tokens are then in turn written-out to the auto-generated
preload/{wrappers.c,exported.h}.

This is necessary for cases where we need to use the autoconf
defines to figure out what interfaces should be wrapped and
which ones shouldn't. As an example, while the FTS interface is
wrapped, it's not necessarily provided by the libc, resulting in
compilation errors.

The matching rationale is that any ^#[a-z] range is matched as
a pre-processor token, and written-out to the generation buffers.
This seemed like a more reasonable approach than having to special
case every possible token, especially as interface.master already
has some existing formatting rules and conventions.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 25 insertions, 2 deletions

diff --git a/preload/gen-interface.pl b/preload/gen-interface.pl
index 4691932..f6a0867 100755
--- a/preload/gen-interface.pl
+++ b/preload/gen-interface.pl
@@ -736,28 +736,51 @@ sub command_export {
 # Reads lines from standard input and call the above functions
 # to perform actions.
 my $line;
+my $token_cache;		# cached pre-processor token
+
 while ($line = <STDIN>) {
-	next if ($line =~ m/^\s*#/);	# skip comment lines
 	next if ($line =~ m/^\s*$/);	# skip empty lines
 
 	while($line =~ s/\\$//) {
+		# Kill trailing whitespace when joining lines
+		$line =~ s/\s$//;
 		# line ends with \, glue next line to this one
 		my $nextline = <STDIN>;
 		$line .= $nextline;
 		if($debug) { printf "Continued: '%s'\n", $nextline; }
 	}
 
+	# '#' lines are special cased, they will either be comments
+	# or pre-processor directives.
+	if ($line =~ m/^\s*#/) {
+		# skip anything that's an obvious comment
+		next if ($line =~ m/^\s*#\s/);
+		next if ($line =~ m/^\s*#[A-Z]/);
+		next if ($line =~ m/^\s*#\s*$/);
+		$wrappers_c_buffer .= $token_cache = $line;
+		next
+	}
+
 	# Add the line as comment to the output C file
 	my $src_comment = $line;
-	$src_comment =~ s/\n/\n * /g;
+	$src_comment =~ s/\n/\n */g;
 	$wrappers_c_buffer .= "/*$src_comment\n*/\n";
 
 	# replace multiple whitespaces by single spaces:
 	$line =~ s/\s+/ /g;
 
+	# Kill off trailing whitespace.
+	$line =~ s/\s$//;
+
 	# Split to fields. 1st=command, 2nd=function, 3rd=modifiers
 	my @field = split(/\s*:\s*/, $line);
 
+	# Order the cached pre-processor token first
+	if ($token_cache) {
+		$export_h_buffer .= $token_cache;
+		$token_cache = "";
+	}
+
 	if(($field[0] eq 'WRAP') || ($field[0] eq 'GATE')) {
 		# Generate a wrapper of a gate
 		command_wrap_or_gate(@field);