Largely re-write gentree.pl

From: Trent Piepho <xyzzy@speakeasy.org>

Mostly re-write gentree.pl to make a few improvements:

About three times faster

Correctly processes BTTV_VERSION_CODE checks

Properly handles #elif

Doesn't need absolute path names specified in command line arguments

Improved debug output, which now shows input line number

Can handle almost any general expression for a conditional compilation
directive.  Can understand all these:
 #if 0
 #ifdef BROKEN_XAWTV
 #ifndef MM_KERNEL
 #if defined(STV0297_CS2)
 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,20)
 #elif defined(MM_KERNEL) || !BROKEN_XAWTV
 #if BTTV_VERSION_CODE > KERNEL_VERSION(0,8,0) || defined(BROKEN_XAWTV)
 #if (1 > 2) || (I2C_PEC && defined(I2C_CLASS_TV_ANALOG))
 #ifndef CONFIG_XC3028 /* Keep   */      <- knows to keep this one in the code

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

1 files changed, 165 insertions, 317 deletions

diff --git a/v4l/scripts/gentree.pl b/v4l/scripts/gentree.pl
index 1b4e44f26..2f918468e 100755
--- a/v4l/scripts/gentree.pl
+++ b/v4l/scripts/gentree.pl
@@ -1,45 +1,93 @@
 #!/usr/bin/perl
+#
+# Original version by Mauro Carvalho Chehab
+# Largely re-written (C) 2007 Trent Piepho <xyzzy@speakeasy.org>
+#
+# Theory of Operation
+#
+# This acts as a sort of mini version of cpp, which will process
+# #if/#elif/#ifdef/etc directives to strip out code used to support
+# multiple kernel versions or otherwise not wanted to be sent upstream to
+# git.
+#
+# Conditional compilation directives fall into two catagories,
+# "processed" and "other".  The "other" directives are ignored and simply
+# output as they come in without changes (see 'keep' exception).  The
+# "processed" variaty are evaluated and only the lines in the 'true' part
+# are kept, like cpp would do.
+#
+# If gentree knows the result of an expression, that directive will be
+# "processed", otherwise it will be an "other".  gentree knows the value
+# of LINUX_VERSION_CODE, BTTV_VERSION_CODE, the KERNEL_VERSION(x,y,z)
+# macro, numeric constants like 0 and 1, and a few defines like MM_KERNEL
+# and STV0297_CS2.
+#
+# An exception is if the comment "/*KEEP*/" appears after the expression,
+# in which case that directive will be considered an "other" and not
+# processed, other than to remove the keep comment.
+#
+# Known bugs:
+# don't specify the root directory e.g. '/' or even '////'
+# directives continued with a back-slash will always be ignored
+# you can't modify a source tree in-place, i.e. source dir == dest dir
+
 use strict;
 use File::Find;
 use Fcntl ':mode';
 
-my $VER = shift;
+my $VERSION = shift;
 my $SRC = shift;
 my $DESTDIR = shift;
-my $extra;
-
-
-#$VER = "2.6.14"			if !defined($VER);
-#$SRC   = "../linux"		if !defined($SRC);
-#$DESTDIR = "/tmp/linux"		if !defined($DESTDIR);
 
 if (!defined($DESTDIR)) {
 	print "Usage:\ngentree.pl\t<version> <source dir> <dest dir>\n\n";
 	exit;
 }
 
-my ($VERSION,$CODE) = &kernel_version;
+my $BTTVCODE = KERNEL_VERSION(0,9,17);
+my ($LINUXCODE, $extra) = kernel_version($VERSION);
 my $DEBUG = 0;
 
+my %defs = (
+	'LINUX_VERSION_CODE' => $LINUXCODE,
+	'BTTV_VERSION_CODE' => $BTTVCODE,
+	'_COMPAT_H' => 0,
+	'MM_KERNEL' => ($extra =~ /-mm/)?1:0,
+	'BROKEN_XAWTV' => 0,
+	'STV0297_CS2' => 0,
+	'HAVE_VIDEO_BUF_DVB' => 1,
+	'I2C_PEC' => 1,
+	'I2C_DF_DUMMY' => 0,
+	'CONFIG_XC3028' => 0,
+	'I2C_CLASS_TV_ANALOG' => 1,
+	'I2C_CLASS_TV_DIGITAL' => 1);
 
 #################################################################
 # helpers
 
-sub kernel_version() {
-	my ($ver,$code);
-
-	$code = 0;
-	$ver = $VER;
-
-	$ver =~ m/(\d)\.(\d)\.([0-9]*(.*))/;
-	my $v1 = $1;
-	my $v2 = $2;
-	my $v3 = $3;
-	$extra = $4;
-
-	$code = $v1*65536 + $v2*256 + $v3;
+sub kernel_version($) {
+	$_[0] =~ m/(\d+)\.(\d+)\.(\d+)(.*)/;
+	return ($1*65536 + $2*256 + $3, $4);
+}
 
-	return ($ver,$code);
+# used in eval()
+sub KERNEL_VERSION($$$) { return $_[0]*65536 + $_[1]*256 + $_[2]; }
+
+sub evalexp($) {
+	local $_ = shift;
+	s|/\*.*?\*/||go;	# delete /* */ comments
+	s|//.*$||o;		# delete // comments
+	s/\bdefined\s*\(/(/go;	# defined(foo) to (foo)
+	while (/\b([_A-Za-z]\w*)\b/go) {
+		if (exists $defs{$1}) {
+			my $id = $1; my $pos = $-[0];
+			s/$id/$defs{$id}/;
+			pos = $-[0];
+		} elsif ($1 ne 'KERNEL_VERSION') {
+			return(undef);
+		}
+	}
+	return(eval($_) ? 1 : 0);
 }
 
 #################################################################
@@ -47,298 +95,116 @@ sub kernel_version() {
 
 sub filter_source ($$) {
 	my ($in,$out) = @_;
-	my ($line,$mmkernel);
+	my $line;
 	my $level=0;
 	my %if = ();
-	my %state =();
-	my $print=0;
+	my %state = ();
 
-	if ($extra =~ m/\-mm/) {
-		$mmkernel = 1;
-	} else {
-		$mmkernel = 0;
+	my @dbgargs = \($level, %state, %if, $line);
+	sub dbgline($\@) {
+		my $level = ${$_[1][0]};
+		printf STDERR ("/* BP %4d $_[0] state=$_[1][1]->{$level} if=$_[1][2]->{$level} level=$level (${$_[1][3]}) */\n", $.) if $DEBUG;
 	}
 
-	open IN,  "<$in";
-	open OUT, ">$out";
+	open IN, '<', $in or die "Error opening $in: $!\n";
+	open OUT, '>', $out or die "Error opening $out: $!\n";
 
-	print STDERR "File: $in, for kernel $VERSION($CODE)/\n" if $DEBUG;
+	print STDERR "File: $in, for kernel $VERSION($LINUXCODE)/\n" if $DEBUG;
 
 	while ($line = <IN>) {
-		if ($line =~ m/^#include \"compat.h\"/) {
-			next;
-		}
-#		if ($line =~ m/[\$]Id:/) {
-#			next;
-#		}
-		if ($line =~ /^\s*#\s*ifdef\s+MM_KERNEL/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = $mmkernel;
-			print STDERR "/* BP #if MM_KERNEL state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*ifdef\s+_COMPAT_H/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 0;
-			print STDERR "/* BP #if MM_KERNEL state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ m|^\s*\#\s*if\s+0\s*\/[\*]\s*[Kk][Ee].[Pp]\s*[\*]\/(.*)|) {
-			if ($1 eq ";") {
-				print OUT "#if 0\n";
-			} else {
-				print OUT "#if 0$1\n";
-			}
-			chomp($line);
+		chomp $line;
+		next if ($line =~ m/^#include \"compat.h\"/o);
+#		next if ($line =~ m/[\$]Id:/);
+
+		# For "#if 0 /*KEEP*/;" the ; should be dropped too
+		if ($line =~ m@^\s*#\s*if(n?def)?\s.*?(\s*/\*\s*(?i)keep\s*\*/;?)@) {
 			$state{$level} = "ifother";
-			$if{$level} = 0;
-			print STDERR "/* BP #if 0 (keep) state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*ifdef\s+STV0297_CS2/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 0;
-			print STDERR "/* BP #if 0 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*ifndef\s+BROKEN_XAWTV/) {
-			chomp($line);
-			$state{$level} = "if";
 			$if{$level} = 1;
-			print STDERR "/* BP #if 0 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
+			dbgline "#if$1 (keep)", @dbgargs;
+			$line =~ s/\Q$2\E//;
 			$level++;
-			next;
 		}
-		if ($line =~ /^\s*#\s*ifndef\s+STV0297_CS2/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 1;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*if\s+0/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 0;
-			print STDERR "/* BP #if 0 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ m|^\s*\#\s*if\s+1\s*\/[\*]\s*[Kk][Ee].[Pp]\s*[\*]\/(.*)|) {
-			print OUT "#if 1$1\n";
+		# handle all ifdef/ifndef lines
+		elsif ($line =~ /^\s*#\s*if(n?)def\s*(\w+)/o) {
+			if (exists $defs{$2}) {
+				$state{$level} = 'if';
+				$if{$level} = ($1 eq 'n') ? !$defs{$2} : $defs{$2};
+				dbgline "#if$1def $2", @dbgargs;
+				$level++;
+				next;
+			}
 			$state{$level} = "ifother";
 			$if{$level} = 1;
-			print STDERR "/* BP #if 1 (keep) state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
+			dbgline "#if$1def (other)", @dbgargs;
 			$level++;
-			next;
 		}
-		if ($line =~ /^\s*#\s*if\s+1/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 1;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*if.*HAVE_VIDEO_BUF_DVB/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 1;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*if.*CONFIG_XC3028/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 0;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*if.*I2C_CLASS_TV_ANALOG/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 1;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*ifndef.\s*I2C_DF_DUMMY/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 1;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*ifndef\s+I2C_PEC/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 0;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*ifdef\s+I2C_PEC/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 1;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*if.*I2C_CLASS_TV_DIGITAL/) {
-			chomp($line);
-			$state{$level} = "if";
-			$if{$level} = 1;
-			print STDERR "/* BP #if 1 state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*if.*BTTV_VERSION_CODE/) {
-			chomp($line);
-			$line =~ s@^#if\s*@@;
-			$line =~ s@BTTV_VERSION_CODE@\$CODE@;
-			$line =~ s@KERNEL_VERSION\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)@
-					sprintf("%d",$1*65536 + $2*256 + $3) @eg;
-			$if{$level} = eval $line;
-			$state{$level} = "if";
-			print STDERR "/* BP #if BTTV_VERSION_CODE state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*if.*LINUX_VERSION_CODE/) {
-			chomp($line);
-			$line =~ s@^#if\s*@@;
-			$line =~ s@LINUX_VERSION_CODE@\$CODE@g;
-			print STDERR "/* BP orig: ($line) */\n" if $DEBUG;
-
-			$line =~ s@KERNEL_VERSION\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)@
-					sprintf("%d",$1*65536 + $2*256 + $3) @eg;
-			$if{$level} = eval $line;
-			$state{$level} = "if";
-			print STDERR "/* BP #if LINUX_VERSION_CODE state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*elif.*LINUX_VERSION_CODE/) {
-			chomp($line);
-			if ( !$level ) {
-				 die "elif without if";
+		# handle all ifs
+		elsif ($line =~ /^\s*#\s*if\s+(.*)$/o) {
+			my $res = evalexp($1);
+			if (defined $res) {
+				$state{$level} = 'if';
+				$if{$level} = $res;
+				dbgline '#if '.($res?'(yes)':'(no)'), @dbgargs;
+				$level++;
+				next;
+			} else {
+				$state{$level} = 'ifother';
+				$if{$level} = 1;
+				dbgline '#if (other)', @dbgargs;
+				$level++;
 			}
+		}
+		# handle all elifs
+		elsif ($line =~ /^\s*#\s*elif\s+(.*)$/o) {
+			my $exp = $1;
 			$level--;
-			if ( $if{$level} ) {
-				# Else is 0
+			$level < 0 and die "more elifs than ifs";
+			$state{$level} =~ /if/ or die "unmatched elif";
+
+			if ($state{$level} eq 'if' && !$if{$level}) {
+				my $res = evalexp($exp);
+				defined $res or die 'moving from if to ifother';
+				$state{$level} = 'if';
+				$if{$level} = $res;
+				dbgline '#elif1 '.($res?'(yes)':'(no)'), @dbgargs;
+				$level++;
+				next;
+			} elsif ($state{$level} ne 'ifother') {
 				$if{$level} = 0;
-				$state{$level} = "elif";
-				print STDERR "/* BP #if LINUX_VERSION_CODE state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-
+				$state{$level} = 'elif';
+				dbgline '#elif0', @dbgargs;
 				$level++;
 				next;
 			}
-
-			$line =~ s@^#if\s*@@;
-			$line =~ s@LINUX_VERSION_CODE@\$CODE@g;
-			print STDERR "/* BP orig: ($line) */\n" if $DEBUG;
-
-			$line =~ s@KERNEL_VERSION\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)@
-					sprintf("%d",$1*65536 + $2*256 + $3) @eg;
-			$if{$level} = eval $line;
-			$state{$level} = "if";
-			print STDERR "/* BP #if LINUX_VERSION_CODE state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-			next;
-		}
-		if ($line =~ /^\s*#\s*if\s/) {
-			$state{$level} = "ifother";
-			$if{$level} = 1;
-			print STDERR "/* BP $line state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			$level++;
-		}
-
-		if ($line =~ /^\s*#\s*ifdef/) {
-			$state{$level} = "ifother";
-			$if{$level} = 1;
-			print STDERR "/* BP $line state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
 			$level++;
 		}
-
-		if ($line =~ /^\s*#\s*ifndef/) {
-			$state{$level} = "ifother";
-			$if{$level} = 1;
-			print STDERR "/* BP $line state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
+		elsif ($line =~ /^\s*#\s*else/o) {
+			$level--;
+			$level < 0 and die "more elses than ifs";
+			$state{$level} =~ /if/ or die "unmatched else";
+			$if{$level} = !$if{$level} if ($state{$level} eq 'if');
+			$state{$level} =~ s/^if/else/o; # if -> else, ifother -> elseother, elif -> elif
+			dbgline '#else', @dbgargs;
 			$level++;
+			next if $state{$level-1} !~ /other$/o;
 		}
-
-		if ($level) {
-			if ($state{$level-1} eq "if" && $line =~ /^\s*#\s*else/) {
-				$state{$level-1} = "else";
-				print STDERR "/* BP #else state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-				next;
-			}
-		}
-		if ($line =~ /^\s*#\s*endif/) {
-			if ($level) {
-				$level--;
-
-				print STDERR "/* BP #endif state=$state{$level} if=$if{$level} level=$level ($line) */\n" if $DEBUG;
-			} else {
-				 die "more endifs than ifs";
-			}
-			if ($state{$level} ne "ifother") {
-				next;
-			}
-		}
-		if ($level == 0) {
-			print OUT $line;
-		} else {
-			my $i=0,$print=1;
-			for ($i=0;$i<$level;$i++) {
-				if (!($state{$i} eq "if"   &&  $if{$i} ||
-				      $state{$i} eq "else" && !$if{$i}) &&
-				      $state{$i} ne "ifother" ) {
-					$print=0;
-					chomp($line);
-					print STDERR "/* BP DEL $line state=$state{$i} if=$if{$i} level=$i */\n" if $DEBUG;
-				}
-			}
-
-			if ($print) {
-				print OUT $line;
+		elsif ($line =~ /^\s*#\s*endif/o) {
+			$level--;
+			$level < 0 and die "more endifs than ifs";
+			dbgline '#endif', @dbgargs;
+			next if $state{$level} !~ /other$/o;
+		}
+
+		my $print = 1;
+		for (my $i=0;$i<$level;$i++) {
+			next if $state{$i} =~ /other$/o;	# keep code in ifother/elseother blocks
+			if (!$if{$i}) {
+				$print = 0;
+				dbgline 'DEL', @{[\$i, \%state, \%if, \$line]};
+				last;
 			}
 		}
-	}
-	close IN;
-	close OUT;
-}
-
-sub filter_dest ($$) {
-	my ($in,$out) = @_;
-	my ($line,$if,$state,$mmkernel);
-
-	if ($extra =~ "/\-mm/") {
-		$mmkernel = 1;
-	} else {
-		$mmkernel = 0;
-	}
-
-	open IN,  "<$in";
-	open OUT, ">$out";
-
-	while ($line = <IN>) {
-		if ($line =~ m/[\$]Id:.*/) {
-			next;
-		}
-		print OUT $line;
+		print OUT "$line\n" if $print;
 	}
 	close IN;
 	close OUT;
@@ -348,54 +214,36 @@ sub filter_dest ($$) {
 
 sub parse_dir {
 	my $file = $File::Find::name;
-	my $srcdir=$SRC;
 
-	if ($file =~ /CVS/) {
-		return;
-	}
-
-	if ($file =~ /\~$/) {
-		return;
-	}
+	return if ($file =~ /CVS/);
+	return if ($file =~ /~$/);
 
-	my $mode = (lstat("$file"))[2];
+	my $f2 = $file;
+	$f2 =~ s/^\Q$SRC\E/$DESTDIR/;
 
+	my $mode = (stat($file))[2];
 	if ($mode & S_IFDIR) {
+		print("mkdir -p '$f2'\n");
+		system("mkdir -p '$f2'");  # should check for error
 		return;
 	}
-
-	$srcdir =~ s/(.)/\[$1\]/g;
-	my $f2 = $file;
-
-	$f2 =~ s,^$srcdir,$DESTDIR/,;
 	print "from $file to $f2\n";
 
-	my $tmp = "/tmp/src.$$";
 	if ($file =~ m/.*\.[ch]$/) {
-		filter_source("$file","$tmp");
+		filter_source($file, $f2);
 	} else {
-	system("cp $file $tmp");
+		system("cp $file $f2");
 	}
-
-	my $dir = $f2;
-	$dir =~ s,(.*)[/][^/]*$,$1,;
-
-	print("mkdir -p $dir\n");
-	system("mkdir -p $dir\n");
-	system("cp $tmp $f2");
-	unlink $tmp;
 }
 
 
 # main
 
-my $patchtmploc = "/tmp/temp.patch";
+printf "kernel is %s (0x%x)\n",$VERSION,$LINUXCODE;
 
-printf <<EOF,$VER,$CODE;
-kernel is %s (0x%x)
-EOF
+# remove any trailing slashes from dir names.  don't pass in just '/'
+$SRC =~ s|/*$||; $DESTDIR =~ s|/*$||;
 
 print "finding files at $SRC\n";
 
-
-find(\&parse_dir, $SRC);
+find({wanted => \&parse_dir, no_chdir => 1}, $SRC);